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  • 1.
    Abdelhamid, Hani Nasser
    et al.
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden.;Assiut Univ, Dept Chem, Adv Multifunct Mat Lab, Assiut 71515, Egypt..
    El-Zohry, Ahmed M.
    Uppsala Univ, Dept Chem, Angstrom Labs, POB 523, S-75120 Uppsala, Sweden..
    Cong, Jiayan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Thersleff, Thomas
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Karlsson, Karl Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Zou, Xiaodong
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Towards implementing hierarchical porous zeolitic imidazolate frameworks in dye-sensitized solar cells2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 190723Article in journal (Refereed)
    Abstract [en]

    A one-pot method for encapsulation of dye, which can be applied for dye-sensitized solar cells (DSSCs), and synthesis of hierarchical porous zeolitic imidazolate frameworks (ZIF-8), is reported. The size of the encapsulated dye tunes the mesoporosity and surface area of ZIF-8. The mesopore size, Langmuir surface area and pore volume are 15 nm, 960-1500 m(2). g(-1) and 0.36-0.61 cm(3). g(-1), respectively. After encapsulation into ZIF-8, the dyes show longer emission lifetimes (greater than 4-8-fold) as compared to the corresponding non-encapsulated dyes, due to suppression of aggregation, and torsional motions.

  • 2.
    Abdelhamid, Hani Nasser
    et al.
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden;Assiut Univ, Dept Chem, Adv Multifunct Mat Lab, Assiut 71515, Egypt.
    El-Zohry, Ahmed M.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström.
    Cong, Jiayan
    KTH Royal Inst Technol, Dept Chem, Appl Phys Chem, Tekn Ringen 30, S-10044 Stockholm, Sweden.
    Thersleff, Thomas
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden.
    Karlsson, Martin
    KTH Royal Inst Technol, Dept Chem, Appl Phys Chem, Tekn Ringen 30, S-10044 Stockholm, Sweden.
    Kloo, Lars
    KTH Royal Inst Technol, Dept Chem, Appl Phys Chem, Tekn Ringen 30, S-10044 Stockholm, Sweden.
    Zou, Xiaodong
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden.
    Towards implementing hierarchical porous zeolitic imidazolate frameworks in dye-sensitized solar cells2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 190723Article in journal (Refereed)
    Abstract [en]

    A one-pot method for encapsulation of dye, which can be applied for dye-sensitized solar cells (DSSCs), and synthesis of hierarchical porous zeolitic imidazolate frameworks (ZIF-8), is reported. The size of the encapsulated dye tunes the mesoporosity and surface area of ZIF-8. The mesopore size, Langmuir surface area and pore volume are 15 nm, 960-1500 m(2). g(-1) and 0.36-0.61 cm(3). g(-1), respectively. After encapsulation into ZIF-8, the dyes show longer emission lifetimes (greater than 4-8-fold) as compared to the corresponding non-encapsulated dyes, due to suppression of aggregation, and torsional motions.

  • 3.
    Abdelhamid, Hani Nasser
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK). Assiut University, Egypt.
    El-Zohry, Ahmed M.
    Cong, Jiayan
    Thersleff, Thomas
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Karlsson, Martin
    Kloo, Lars
    Zou, Xiaodong
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Towards implementing hierarchical porous zeolitic imidazolate frameworks in dye-sensitized solar cells2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 190723Article in journal (Refereed)
    Abstract [en]

    A one-pot method for encapsulation of dye, which can be applied for dye-sensitized solar cells (DSSCs), and synthesis of hierarchical porous zeolitic imidazolate frameworks (ZIF-8), is reported. The size of the encapsulated dye tunes the mesoporosity and surface area of ZIF-8. The mesopore size, Langmuir surface area and pore volume are 15 nm, 960-1500 m(2). g(-1) and 0.36-0.61 cm(3). g(-1), respectively. After encapsulation into ZIF-8, the dyes show longer emission lifetimes (greater than 4-8-fold) as compared to the corresponding non-encapsulated dyes, due to suppression of aggregation, and torsional motions.

  • 4.
    Adalat, Mohsin
    et al.
    COSMOSE Research Group, Department of Computer Science, COMSATS University Islamabad, Islamabad, Pakistan.
    Niazi, Muaz A.
    COSMOSE Research Group, Department of Computer Science, COMSATS University Islamabad, Islamabad, Pakistan.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Variations in power of opinion leaders in online communication networks2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 10, article id 180642Article in journal (Refereed)
    Abstract [en]

    Online social media has completely transformed how we communicate with each other. While online discussion platforms are available in the form of applications and websites, an emergent outcome of this transformation is the phenomenon of ‘opinion leaders’. A number of previous studies have been presented to identify opinion leaders in online discussion networks. In particular, Feng (2016 Comput. Hum. Behav. 54, 43–53. (doi:10.1016/j.chb.2015.07.052)) has identified five different types of central users besides outlining their communication patterns in an online communication network. However, the presented work focuses on a limited time span. The question remains as to whether similar communication patterns exist that will stand the test of time over longer periods. Here, we present a critical analysis of the Feng framework both for short-term as well as for longer periods. Additionally, for validation, we take another case study presented by Udanor et al. (2016 Program 50, 481–507. (doi:10.1108/PROG-02-2016-0011)) to further understand these dynamics. Results indicate that not all Feng-based central users may be identifiable in the longer term. Conversation starter and influencers were noted as opinion leaders in the network. These users play an important role as information sources in long-term discussions. Whereas network builder and active engager help in connecting otherwise sparse communities. Furthermore, we discuss the changing positions of opinion leaders and their power to keep isolates interested in an online discussion network.

  • 5.
    Alström, Per
    et al.
    Swedish Univ Agr Sci, Swedish Species Informat Ctr, POB 7007, S-75007 Uppsala, Sweden; Chinese Acad Sci, Inst Zool, Key Lab Zool Systemat & Evolut, Beijing 100101, Peoples R China.
    Jonsson, Knud A
    Jon, Fjeldså
    Ödeen, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Ericson, Per G. P.
    Irestedt, Martin
    Dramatic niche shifts and morphological change in two insular bird species2015In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 2, no 3, article id 140364Article in journal (Refereed)
    Abstract [en]

    Colonizations of islands are often associated with rapid morphological divergence. We present two previously unrecognized cases of dramatic morphological change and niche shifts in connection with colonization of tropical forest-covered islands. These evolutionary changes have concealed the fact that the passerine birds madanga, Madanga ruficollis, from Buru, Indonesia, and São Tomé shorttail, Amaurocichla bocagii, from São Tomé, Gulf of Guinea, are forest-adapted members of the family Motacillidae (pipits and wagtails). We show that Madanga has diverged mainly in plumage, which may be the result of selection for improved camouflage in its new arboreal niche, while selection pressures for other morphological changes have probably been weak owing to preadaptations for the novel niche. By contrast, we suggest thatAmaurocichla's niche change has led to divergence in both structure and plumage.

  • 6.
    Ardalan, Arman
    et al.
    KTH, School of Biotechnology (BIO), Gene Technology. Division of Animal Biotechnology and Genomics, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran 14965/161, Iran.
    Oskarsson, Mattias C. R.
    KTH, School of Biotechnology (BIO), Gene Technology.
    van Asch, Barbara
    Rabakonandriania, Elisabeth
    Savolainen, Peter
    KTH, School of Biotechnology (BIO), Gene Technology.
    African origin for Madagascan dogs revealed by mtDNA analysis2015In: Royal Society Open Science, E-ISSN 2054-5703Article in journal (Refereed)
    Abstract [en]

    Madagascar was one of the last major land masses to be inhabited by humans. It was initially colonized by Austronesian speaking Indonesians 1500–2000 years ago, but subsequent migration from Africa has resulted in approximately equal genetic contributions from Indonesia and Africa, and the material culture has mainly African influences. The dog, along with the pig and the chicken, was part of the Austronesian Neolithic culture, and was furthermore the only domestic animal to accompany humans to every continent in ancient times. To illuminate Madagascan cultural origins and track the initial worldwide dispersal of dogs, we here investigated the ancestry of Madagascan dogs. We analysed mtDNA control region sequences in dogs from Madagascar (n=145) and compared it with that from potential ancestral populations in Island Southeast Asia (n=219) and sub-Saharan Africa (n=493). We found that 90% of the Madagascan dogs carried a haplotype that was also present in sub-Saharan Africa and that the remaining lineages could all be attributed to a likely origin in Africa. By contrast, only 26% of Madagascan dogs shared haplotypes with Indonesian dogs, and one haplotype typical for Austronesian dogs, carried by more than 40% of Indonesian and Polynesian dogs, was absent among the Madagascan dogs. Thus, in contrast to the human population, Madagascan dogs seem to trace their origin entirely from Africa. These results suggest that dogs were not brought to Madagascar by the initial Austronesian speaking colonizers on their transoceanic voyage, but were introduced at a later stage, together with human migration and cultural influence from Africa.

  • 7.
    Bengtsson, Daniel
    et al.
    Linnaeus University.
    Safi, Kamran
    Tyskland.
    Avril, Alexis
    Linnaeus University.
    Fiedler, Wolfgang
    Tyskland.
    Wikelski, Martin
    Tyskland.
    Gunnarsson, Gunnar
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Tolf, Conny
    Linnaeus University.
    Olsen, Björn
    Uppsala University.
    Waldenström, Jonas
    Linnaeus University.
    Does influenza A virus infection affect movement behaviour during stopover in its wild reservoir host?2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 2, article id 150633Article in journal (Refereed)
    Abstract [en]

    The last decade has seen a surge in research on avian influenza A viruses (IAVs), in part fuelled by the emergence, spread and potential zoonotic importance of highly pathogenic virus subtypes. The mallard (Anas platyrhynchos) is the most numerous and widespread dabbling duck in the world, and one of the most important natural hosts for studying IAV transmission dynamics. In order to predict the likelihood of IAV transmission between individual ducks and to other hosts, as well as between geographical regions, it is important to understand how IAV infection affects the host. In this study, we analysed the movements of 40 mallards equipped with GPS transmitters and three-dimensional accelerometers, of which 20 were naturally infected with low pathogenic avian influenza virus (LPAIV), at a major stopover site in the Northwest European flyway. Movements differed substantially between day and night, as well as between mallards returning to the capture site and those feeding in natural habitats. However, movement patterns did not differ between LPAIV infected and uninfected birds. Hence, LPAIV infection probably does not affect mallard movements during stopover, with high possibility of virus spread along the migration route as a consequence.

  • 8.
    Bengtsson, Daniel
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Safi, Kamran
    Max Planck Institute for Ornithology, Germany;University of Konstanz, Germany.
    Avril, Alexis
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Fiedler, Wolfgang
    Max Planck Institute for Ornithology, Germany;University of Konstanz, Germany.
    Wikelski, Martin
    Max Planck Institute for Ornithology, Germany;University of Konstanz, Germany.
    Gunnarsson, Gunnar
    Kristianstad University.
    Elmberg, Johan
    Kristianstad University.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Olsen, Björn
    Uppsala University.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Does influenza A virus infection affect movement behaviour during stopover in its wild reservoir host?2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 2, p. 1-11, article id 150633Article in journal (Refereed)
    Abstract [en]

    The last decade has seen a surge in research on avian influenza A viruses (IAVs), in part fuelled by the emergence, spread and potential zoonotic importance of highly pathogenic virus subtypes. The mallard (Anas platyrhynchos) is the most numerous and widespread dabbling duck in the world, and one of the most important natural hosts for studying IAV transmission dynamics. In order to predict the likelihood of IAV transmission between individual ducks and to other hosts, as well as between geographical regions, it is important to understand how IAV infection affects the host. In this study, we analysed the movements of 40 mallards equipped with GPS transmitters and three-dimensional accelerometers, of which 20 were naturally infected with low pathogenic avian influenza virus (LPAIV), at a major stopover site in the Northwest European flyway. Movements differed substantially between day and night, as well as between mallards returning to the capture site and those feeding in natural habitats. However, movement patterns did not differ between LPAIV infected and uninfected birds. Hence, LPAIV infection probably does not affect mallard movements during stopover, with high possibility of virus spread along the migration route as a consequence.

  • 9.
    Bhattacharyya, Shubhankar
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Kaushik, Hatua
    Department of Chemistry, IIEST, Shibpur.
    Theoretical investigation of banert cascade reaction2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 4, article id 171075Article in journal (Refereed)
    Abstract [en]

    Computational inside of Banert cascade reaction for triazole formation is studied with B3LYP/6-31G(d,p) level of theory. The reaction proceeds mainly by SN2 initial chloride displacement rather than SN2 -type attack. Furthermore, according to the rate of reaction calculation, SN2 displacement is much faster than SN2 displacement in the order of 8. The [3,3]-sigmatropic rearrangement for the conversion of propargyl azide into triazafulvene has been proved as the rate-determining step having highest activation energy parameter. Solvent effect on total course of reaction has been found negligible. Furthermore, effects of different density functional theory functionals and functional groups on activation energies of [3,3]-sigmatropic rearrangement of propargyl azide were also studied. BHHLYP, ωB97XD, M062X and BMK calculated ∆G are consistent with B3LYP.

  • 10.
    Brodka, Piotr
    et al.
    Wroclaw Univ Sci & Technol, Fac Comp Sci & Management, Dept Computat Intelligence, Wroclaw, Poland.
    Chmiel, Anna
    Warsaw Univ Technol, Fac Phys, Warsaw, Poland.
    Magnani, Matteo
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computing Science.
    Ragozini, Giancarlo
    Univ Naples Federico II, Dept Polit Sci, Naples, Campania, Italy.
    Quantifying layer similarity in multiplex networks: a systematic study2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 8, article id 171747Article in journal (Refereed)
    Abstract [en]

    Computing layer similarities is an important way of characterizing multiplex networks because various static properties and dynamic processes depend on the relationships between layers. We provide a taxonomy and experimental evaluation of approaches to compare layers in multiplex networks. Our taxonomy includes, systematizes and extends existing approaches, and is complemented by a set of practical guidelines on how to apply them.

  • 11.
    Buckland, Philip I.
    et al.
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies, Environmental Archaeology Lab.
    Bateman, Mark D.
    Department of Geography, University of Sheffield, Sheffield S10 2TN, UK.
    Bennike, Ole
    GEUS Geological Survey of Denmark and Greenland, ØsterVoldgade 10, Copenhagen 1350, Denmark.
    Buckland, Paul C.
    Chase, Brian M.
    Institut des Sciences de l’Evolution-Montpellier (ISEM), Universite´ de Montpellier, CNRS, EPHE, IRD, Bat 22, CC061, Place Euge`ne Bataillon, 34095 Montpellier cedex 5, France.
    Frederick, Charles
    6Department of Geography and the Environment, The University of Texas at Austin, Austin, TX, USA.
    Greenwood, Malcolm
    Department of Geography, Loughborough University, Leics LE11 3TU, UK.
    Murton, Julian
    Department of Geography, University of Sussex, Brighton BN1 9RH, UK.
    Murton, Della
    Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
    Panagiotakopulu, Eva
    Institute of Geography, University of Edinburgh, Drummond Street, Edinburgh EH8 9XP, UK.
    Mid-Devensian climate and landscape in England: new data from Finningley, South Yorkshire2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 190577Article in journal (Refereed)
    Abstract [en]

    While there is extensive evidence for the Late Devensian, less is known about Early and Middle Devensian (approx. 110-30 ka) climates and environments in the UK. The Greenland ice-core record suggests the UK should have endured multiple changes, but the terrestrial palaeo-record lacks sufficient detail for confirmation from sites in the British Isles. Data from deposits at Finningley, South Yorkshire, can help redress this. A channel with organic silts, dated 40 314-39 552 cal a BP, contained plant macrofossil and insect remains showing tundra with dwarf-shrub heath and bare ground. Soil moisture conditions varied from free draining to riparian, with ponds and wetter vegetated areas. The climate was probably low arctic with snow cover during the winter. Mutual climatic range (MCR), based on Coleoptera, shows the mean monthly winter temperatures of -22 to -2 degrees C and summer ones of 8-14 degrees C. Periglacial structures within the basal gravel deposits and beyond the glacial limits indicate cold-climate conditions, including permafrost. A compilation of MCR reconstructions for other Middle Devensian English sites shows that marine isotope stage 3-between 59 and 28 ka-experienced substantial variation in climate consistent with the Greenland ice-core record. The exact correlation is hampered by temporal resolution, but the Finningley site stadial at approximately 40 ka may correlate with the one of the Greenland stadials 7-11.

  • 12.
    Bélteky, Johan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Agnvall, Beatrix
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Johnsson, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wright, Dominic
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology2016In: Royal Society Open Science, E-ISSN 2054-5703, no 3, article id 160033Article in journal (Refereed)
    Abstract [en]

    The domestication of animals has generated a set of phenotypicmodifications, affecting behaviour, appearance, physiologyand reproduction, which are consistent across a range ofspecies. We hypothesized that some of these phenotypes couldhave evolved because of genetic correlation to tameness,an essential trait for successful domestication. Starting froman outbred population of red junglefowl, ancestor of alldomestic chickens, we selected birds for either high or lowfear of humans for five generations. Birds from the fifthselected generation (S5) showed a divergent pattern of growthand reproduction, where low fear chickens grew larger andproduced larger offspring. To examine underlying geneticmechanisms, we used microarrays to study gene expressionin thalamus/hypothalamus, a brain region involved in fearand stress, in both the parental generation and the S5. Whileparents of the selection lines did not show any differentiallyexpressed genes, there were a total of 33 genes with adjustedp-values below 0.1 in S5. These were mainly related to spermfunction,immunological functions, with only a few known tobe relevant to behaviour. Hence, five generations of divergentselection for fear of humans produced changes in hypothalamicgene expression profiles related to pathways associated withmale reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis thatdomesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.

  • 13. Casini, Michele
    et al.
    Kall, Filip
    Hansson, Martin
    SMHI, Core Services.
    Plikshs, Maris
    Baranova, Tatjana
    Karlsson, Olle
    Lundstrom, Karl
    Neuenfeldt, Stefan
    Gardmark, Anna
    Hjelm, Joakim
    Hypoxic areas, density-dependence and food limitation drive the body condition of a heavily exploited marine fish predator2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 10, article id 160416Article in journal (Refereed)
  • 14.
    Chen, Dong Lei
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Sanchez, Sophie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Tafforeau, Paul
    Estonian Marine Institute, University of Tartu.
    Märss, Tiiu
    Estonian Marine Institute, University of Tartu.
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Development of cyclic shedding teeth from semi-shedding teeth: the inner dental arcade of the stem osteichthyan Lophosteus 2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 5, article id 161084Article in journal (Refereed)
    Abstract [en]

    The numerous cushion-shaped tooth-bearing plates attributed to the stem-group osteichthyan Lophosteus superbus, which are argued here to represent the ancient form of inner dental arcade, display a unique and presumably primitive way of tooth shedding by basal hard tissue resorption. They carry regularly spaced, recumbent, gently recurved teeth arranged in transverse tooth files that diverge towards the lingual margin of the cushion. Three-dimensional (3D) reconstruction from propagation phase contrast synchrotron microtomography (PPC-SRμCT) reveals remnants of the first-generation teeth embedded in the basal plate that have never been discerned in any taxa. These teeth were shed by semi-basal resorption with the periphery of their bases retained as dentine rings. The rings are highly overlapped, which evidences tooth shedding prior to adding the next first-generation tooth. Later teeth at the same sites underwent cyclical replacing and shedding through basal resorption, producing stacks of buried resorption surfaces separated by bone of attachment. The number and spatial arrangement of resorption surfaces elucidates that basal resorption of replacement teeth had taken place at the older tooth sites before the addition of the youngest first-generation teeth at the lingual margin. Thus the replacement tooth buds cannot have been generated by a single permanent dental lamina, but must have arisen either from successional dental laminae associated with the predecessor teeth, or directly from the dental epithelium of these teeth. The virtual histological dissection of these Late Silurian microfossils broadens our understanding of the development of the gnathostome dental systems and the acquisition of the osteichthyan-type of tooth replacement. 

  • 15. Chung, Ning Ning
    et al.
    Jacobs, Guy S.
    Sudoyo, Herawati
    Malik, Safarina G.
    Chew, Lock Yue
    Lansing, J. Stephen
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Santa Fe Institute, USA.
    Cox, Murray P.
    Sex-linked genetic diversity originates from persistent sociocultural processes at microgeographic scales2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 8, article id 190733Article in journal (Refereed)
    Abstract [en]

    Population genetics has been successful at identifying the relationships between human groups and their interconnected histories. However, the link between genetic demography inferred at large scales and the individual human behaviours that ultimately generate that demography is not always clear. While anthropological and historical context are routinely presented as adjuncts in population genetic studies to help describe the past, determining how underlying patterns of human sociocultural behaviour impact genetics still remains challenging. Here, we analyse patterns of genetic variation in village-scale samples from two islands in eastern Indonesia, patrilocal Sumba and a matrilocal region of Timor. Adopting a ‘process modelling’ approach, we iteratively explore combinations of structurally different models as a thinking tool. We find interconnected socio-genetic interactions involving sex-biased migration, lineage-focused founder effects, and on Sumba, heritable social dominance. Strikingly, founder ideology, a cultural model derived from anthropological and archaeological studies at larger regional scales, has both its origins and impact at the scale of villages. Process modelling lets us explore these complex interactions, first by circumventing the complexity of formal inference when studying large datasets with many interacting parts, and then by explicitly testing complex anthropological hypotheses about sociocultural behaviour from a more familiar population genetic standpoint.

  • 16.
    Clement, Alice M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Nysjö, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Long, John A.
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    A new method for reconstructing brain morphology: Applying the brain-neurocranial spatial relationship in an extant lungfish to a fossil endocast2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 7, article id 160307Article in journal (Refereed)
  • 17.
    Den Boer, Wendy
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Swedish Nat Hist Museum, Dept Palaeobiol, S-10405 Stockholm, Sweden.
    Campione, Nicolás E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology. Univ New England, Palaeosci Res Ctr, Sch Environm & Rural Sci, Armidale, NSW 2531, Australia.
    Kear, Benjamin P.
    Uppsala University, Music and Museums, Museum of Evolution.
    Climbing adaptations, locomotory disparity and ecological convergence in ancient stem 'kangaroos'2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 2, article id 181617Article in journal (Refereed)
    Abstract [en]

    Living kangaroos, wallabies and rat-kangaroos (Macropodoidea) constitute the most ecologically diverse radiation of Australasian marsupials. Indeed, even their hallmark bipedal hopping gait has been variously modified for bounding, walking and climbing. However, the origins of this locomotory adaptability are uncertain because skeletons of the most ancient macropodoids are exceptionally rare. Some of the stratigraphically oldest fossils have been attributed to Balbaridae-a clade of potentially quadrupedal stem macropodoids that became extinct during the late Miocene. Here we undertake the first assessment of balbarid locomotion using two-dimensional geometric morphometrics and a correlative multivariate analysis of linear measurements. We selected the astragalus and pedal digit IV ungual as proxies for primary gait because these elements are preserved in the only articulated balbarid skeleton, as well as some unusual early Miocene balbarid-like remains that resemble the bones of modern tree-kangaroos. Our results show that these fossils manifest character states indicative of contrasting locomotory capabilities. Furthermore, predictive modelling reveals similarities with extant macropodoids that employ either bipedal saltation and/or climbing. We interpret this as evidence for archetypal gait versatility, which probably integrated higher-speed hopping with slower-speed quadrupedal progression and varying degrees of scansoriality as independent specializations for life in forest and woodland settings.

  • 18.
    Edvinsson, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Optical quantum confinement and photocatalytic properties in two-, one- and zero-dimensional nanostructures2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 9, article id 180387Article in journal (Refereed)
    Abstract [en]

    Low-dimensional nanomaterials have been explored extensively in the last decades, partly fuelled by the new possibilities for tuning and controlling their electronic properties. In a broader perspective within catalysis, two-, one- and zero-dimensional (2D, 1D and 0D) inorganic nanomaterials represent a bridge between the selectivity of molecular catalysts and the high performance and stability of inorganic catalysts. As a consequence of the low dimensions, higher surface areas are obtained but also introduce new physics and increased tuneability of the electronic states in the nanostructured system. Herein, we derive the commonly used equations for optical transitions and carrier confinement in semiconductors and discuss their effect on the optical and photocatalytic properties of direct band and indirect band gap materials. In particular, the physical properties of the optical and photocatalytic properties of Fe2O3 and ZnO will be used to exemplify the effects of the low dimensionality. Carrier confinement effects with changes in the density of states, band gap/shift of band edges will be outlined together with their effects on the tuneability of the material and their wider application as photocatalytic materials.

  • 19.
    Engblom, Stefan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computational Science.
    Wilson, Daniel B.
    Baker, Ruth E.
    Scalable population-level modelling of biological cells incorporating mechanics and kinetics in continuous time2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, p. 180379:1-17, article id 180379Article in journal (Refereed)
  • 20.
    Enquist, Magnus
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology.
    Lind, Johan
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution. Brooklyn College, USA; Graduate Center of the City University of New York, USA.
    The power of associative learning and the ontogeny of optimal behaviour2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 11, article id 160734Article in journal (Refereed)
    Abstract [en]

    Behaving efficiently (optimally or near-optimally) is central to animals' adaptation to their environment. Much evolutionary biology assumes, implicitly or explicitly, that optimal behavioural strategies are genetically inherited, yet the behaviour of many animals depends crucially on learning. The question of how learning contributes to optimal behaviour is largely open. Here we propose an associative learning model that can learn optimal behaviour in a wide variety of ecologically relevant circumstances. The model learns through chaining, a term introduced by Skinner to indicate learning of behaviour sequences by linking together shorter sequences or single behaviours. Our model formalizes the concept of conditioned reinforcement (the learning process that underlies chaining) and is closely related to optimization algorithms from machine learning. Our analysis dispels the common belief that associative learning is too limited to produce ‘intelligent’ behaviour such as tool use, social learning, self-control or expectations of the future. Furthermore, the model readily accounts for both instinctual and learned aspects of behaviour, clarifying how genetic evolution and individual learning complement each other, and bridging a long-standing divide between ethology and psychology. We conclude that associative learning, supported by genetic predispositions and including the oft-neglected phenomenon of conditioned reinforcement, may suffice to explain the ontogeny of optimal behaviour in most, if not all, non-human animals. Our results establish associative learning as a more powerful optimizing mechanism than acknowledged by current opinion.

  • 21.
    Eriksson, Maertha
    et al.
    Stockholm University, Faculty of Science, Department of Zoology, Functional Morphology.
    Nylin, Sören
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    Carlsson, Mikael A.
    Stockholm University, Faculty of Science, Department of Zoology, Functional Morphology.
    Insect brain plasticity: effects of olfactory input on neuropil size2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 8, article id 190875Article in journal (Refereed)
    Abstract [en]

    Insect brains are known to express a high degree of experience-dependent structural plasticity. One brain structure in particular, the mushroom body (MB), has been attended to in numerous studies as it is implicated in complex cognitive processes such as olfactory learning and memory. It is, however, poorly understood to what extent sensory input per se affects the plasticity of the mushroom bodies. By performing unilateral blocking of olfactory input on immobilized butterflies, we were able to measure the effect of passive sensory input on the volumes of antennal lobes (ALs) and MB calyces. We showed that the primary and secondary olfactory neuropils respond in different ways to olfactory input. ALs show absolute experience-dependency and increase in volume only if receiving direct olfactory input from ipsilateral antennae, while MB calyx volumes were unaffected by the treatment and instead show absolute age-dependency in this regard. We therefore propose that cognitive processes related to behavioural expressions are needed in order for the calyx to show experience-dependent volumetric expansions. Our results indicate that such experience-dependent volumetric expansions of calyces observed in other studies may have been caused by cognitive processes rather than by sensory input, bringing some causative clarity to a complex neural phenomenon.

  • 22.
    Ghirlanda, Stefano
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution. Brooklyn College, USA; Graduate Center of the City University of New York, USA.
    Lind, Johan
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution.
    Enquist, Magnus
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution.
    Memory for stimulus sequences: a divide between humans and other animals?2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 6, article id 161011Article in journal (Refereed)
    Abstract [en]

    Humans stand out among animals for their unique capacities in domains such as language, culture and imitation, yet it has been difficult to identify cognitive elements that are specifically human. Most research has focused on how information is processed after it is acquired, e.g. in problem solving or 'insight' tasks, but we may also look for species differences in the initial acquisition and coding of information. Here, we show that non-human species have only a limited capacity to discriminate ordered sequences of stimuli. Collating data from 108 experiments on stimulus sequence discrimination (1540 data points from 14 bird and mammal species), we demonstrate pervasive and systematic errors, such as confusing a red-green sequence of lights with green-red and green-green sequences. These errors can persist after thousands of learning trials in tasks that humans learn to near perfection within tens of trials. To elucidate the causes of such poor performance, we formulate and test a mathematical model of non-human sequence discrimination, assuming that animals represent sequences as unstructured collections of memory traces. This representation carries only approximate information about stimulus duration, recency, order and frequency, yet our model predicts non-human performance with a 5.9% mean absolute error across 68 datasets. Because human-level cognition requires more accurate encoding of sequential information than afforded by memory traces, we conclude that improved coding of sequential information is a key cognitive element that may set humans apart from other animals.

  • 23. Gilbert, James
    et al.
    Uggla, Caroline
    Stockholm University, Faculty of Social Sciences, Department of Sociology. University College London, UK.
    Mace, Ruth
    Knowing your neighbourhood: local ecology and personal experience predict neighbourhood perceptions in Belfast, Northern Ireland2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 12, article id 160468Article in journal (Refereed)
    Abstract [en]

    Evolutionary theory predicts that humans should adjust their life-history strategies in response to local ecological threats and opportunities in order to maximize their reproductive success. Cues representing threats to individuals' lives and health in modern, Western societies may come in the form of local ages at death, morbidity rate and crime rate in their local area, whereas the adult sex ratio represents a measure of the competition for reproductive partners. These characteristics are believed to have a strong influence over a wide range of behaviours, but whether they are accurately perceived has not been robustly tested. Here, we investigate whether perceptions of four neighbourhood characteristics are accurate across eight neighbourhoods in Belfast, Northern Ireland. We find that median age at death and morbidity rates are accurately perceived, whereas adult sex ratios and crime rates are not. We suggest that both neighbourhood characteristics and personal experiences contribute to the formation of perceptions. This should be considered by researchers looking for associations between area-level factors.

  • 24.
    Gorokhova, Elena
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Shifts in rotifer life history in response to stable isotope enrichment: testing theories of isotope effects on organismal growth2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 3, article id 160810Article in journal (Refereed)
    Abstract [en]

    In ecology, stable isotope labelling is commonly used for tracing material transfer in trophic interactions, nutrient budgets and biogeochemical processes. The main assumption in this approach is that the enrichment with a heavy isotope has no effect on the organism growth and metabolism. This assumption is, however, challenged by theoretical considerations and experimental studies on kinetic isotope effects in vivo. Here, I demonstrate profound changes in life histories of the rotifer Brachionus plicatilis fed N-15-enriched algae (0.4-5.0 at%); i.e. at the enrichment levels commonly used in ecological studies. These findings support theoretically predicted effects of heavy isotope enrichment on growth, metabolism and ageing in biological systems and underline the importance of accounting for such effects when using stable isotope labelling in experimental studies.

  • 25. Hardwicke, Tom E.
    et al.
    Mathur, Maya B.
    MacDonald, Kyle
    Nilsonne, Gustav
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Stanford University, USA; Karolinska Institutet, Sweden.
    Banks, George C.
    Kidwell, Mallory C.
    Mohr, Alicia Hofelich
    Clayton, Elizabeth
    Yoon, Erica J.
    Tessler, Michael Henry
    Lenne, Richie L.
    Altman, Sara
    Long, Bria
    Frank, Michael C.
    Data availability, reusability, and analytic reproducibility: evaluating the impact of a mandatory open data policy at the journal Cognition2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 8, article id 180448Article in journal (Refereed)
    Abstract [en]

    Access to data is a critical feature of an efficient, progressive and ultimately self-correcting scientific ecosystem. But the extent to which in-principle benefits of data sharing are realized in practice is unclear. Crucially, it is largely unknown whether published findings can be reproduced by repeating reported analyses upon shared data ('analytic reproducibility'). To investigate this, we conducted an observational evaluation of a mandatory open data policy introduced at the journal Cognition. Interrupted time-series analyses indicated a substantial post-policy increase in data available statements (104/417, 25% pre-policy to 136/ 174, 78% post-policy), although not all data appeared reusable (23/ 104, 22% pre-policy to 85/136, 62%, post-policy). For 35 of the articles determined to have reusable data, we attempted to reproduce 1324 target values. Ultimately, 64 values could not be reproduced within a 10% margin of error. For 22 articles all target values were reproduced, but 11 of these required author assistance. For 13 articles at least one value could not be reproduced despite author assistance. Importantly, there were no clear indications that original conclusions were seriously impacted. Mandatory open data policies can increase the frequency and quality of data sharing. However, suboptimal data curation, unclear analysis specification and reporting errors can impede analytic reproducibility, undermining the utility of data sharing and the credibility of scientific findings.

  • 26.
    Hedblom, Marcus
    et al.
    Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden; Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Knez, Igor
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Psychology.
    Sang, A. Ode
    Department of Landscape Architecture, Planning and Management, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Gunnarsson, B.
    Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden.
    Evaluation of natural sounds in urban greenery: potential impact for urban nature preservation2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 2, article id 170037Article in journal (Refereed)
    Abstract [en]

    Most humans now live in cities and their main experience of nature is through urban greenery. An increasing number of studies show the importance of urban green spaces for wellbeing, although most of them are based on visual perception. A questionnaire examining people’s evaluations of natural sounds was answered by 1326 individuals living near one of six urban green areas of varying naturalness in the city of Gothenburg, Sweden. Women and the elderly reported greater calmness when hearing bird song and rustling leaves (and placed a higher importance on the richness of bird species) than did men, younger and middle-aged individuals. Independent of age and gender, urban woodlands (high naturalness) had higher evaluations than parks (low naturalness). Our results suggest that to increase positive experiences of urban green areas, demographic variables of gender and age should be taken into account, and settings that mimic nature should be prioritized in planning.

  • 27.
    Holovachov, Oleksandr
    Swedish Museum of Natural History, Department of Zoology.
    Bourlat, Sarah (Contributor)
    Jondelius, Ulf (Contributor)
    Swedish Museum of Natural History, Department of Zoology.
    The choice of taxonomy assignment approach has strong impact on the efficiency of identification of OTUs in marine nematodes2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, article id 170315Article in journal (Refereed)
  • 28.
    Holovachov, Oleksandr
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Haenel, Quiterie
    Bourlat, Sarah
    Jondelius, Ulf
    Swedish Museum of Natural History, Department of Zoology.
    Taxonomy assignment approach determines the efficiency of identification of OTUs in marine nematodes2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 8Article in journal (Refereed)
  • 29. Ingre, Michael
    et al.
    Nilsonne, Gustav
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden; Stanford University, USA.
    Estimating statistical power, posterior probability and publication bias of psychological research using the observed replication rate2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 9, article id 181190Article in journal (Refereed)
    Abstract [en]

    In this paper, we show how Bayes' theorem can be used to better understand the implications of the 36% reproducibility rate of published psychological findings reported by the Open Science Collaboration. We demonstrate a method to assess publication bias and show that the observed reproducibility rate was not consistent with an unbiased literature. We estimate a plausible range for the prior probability of this body of research, suggesting expected statistical power in the original studies of 48-75%, producing (positive) findings that were expected to be true 41-62% of the time. Publication bias was large, assuming a literature with 90% positive findings, indicating that negative evidence was expected to have been observed 55-98 times before one negative result was published. These findings imply that even when studied associations are truly NULL, we expect the literature to be dominated by statistically significant findings.

  • 30.
    Ivanenko, Yevhen
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Nedic, Mitja
    Stockholm University, Sweden.
    Gustafsson, Mats
    Lund University, Sweden.
    Jonsson, B. L. G.
    KTH Royal institute of technology, Sweden.
    Luger, Annemarie
    Stockholm University, Sweden.
    Nordebo, Sven
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Quasi-Herglotz functions and convex optimization2020In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 7, no 1, article id 191541Article in journal (Refereed)
    Abstract [en]

    We introduce the set of quasi-Herglotz functions and demonstrate that it has properties useful in the modelling of non-passive systems. The linear space of quasi-Herglotz functions constitutes a natural extension of the convex cone of Herglotz functions. It consists of differences of Herglotz functions and we show that several of the important properties and modelling perspectives are inherited by the new set of quasi-Herglotz functions. In particular, this applies to their integral representations, the associated integral identities or sum rules (with adequate additional assumptions), their boundary values on the real axis and the associated approximation theory. Numerical examples are included to demonstrate the modelling of a non-passive gain medium formulated as a convex optimization problem, where the generating measure is modelled by using a finite expansion of B-splines and point masses.

  • 31.
    Johanson, Zerina
    et al.
    Nat Hist Museum, Dept Earth Sci, London, England..
    Smith, Moya
    Nat Hist Museum, Dept Earth Sci, London, England.;Kings Coll London, Dent Inst, Tissue Engn & Biophoton, London, England..
    Sanchez, Sophie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology. European Synchrotron Radiat Facil, Grenoble, France..
    Senden, Tim
    Australian Natl Univ, Res Sch Phys & Engn, Dept Appl Math, Canberra, ACT 2601, Australia..
    Trinajstic, Kate
    Curtin Univ, Environm & Agr, Kent St, Perth, WA, Australia..
    Pfaff, Cathrin
    Univ Vienna, Dept Palaeontol, Vienna, Austria..
    Questioning hagfish affinities of the enigmatic Devonian vertebrate Palaeospondylus2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 7, article id 170214Article in journal (Refereed)
    Abstract [en]

    Palaeospondylus gunni Traquair, 1890 is an enigmatic Devonian vertebrate whose taxonomic affinities have been debated since it was first described. Most recently, Palaeospondylus has been identified as a stem-group hagfish (Myxinoidea). However, one character questioning this assignment is the presence of three semicircular canals in the otic region of the cartilaginous skull, a feature of jawed vertebrates. Additionally, new tomographic data reveal that the following characters of crown-group gnathostomes (chondrichthyans + osteichthyans) are present in Palaeospondylus: a longer telencephalic region of the braincase, separation of otic and occipital regions by the otico-occipital fissure, and vertebral centra. As well, a precerebral fontanelle and postorbital articulation of the palatoquadrate are characteristic of certain chondrichthyans. Similarities in the structure of the postorbital process to taxa such as Pucapampella, and possible presence of the ventral cranial fissure, both support a resolution of Pa. gunni as a stem chondrichthyan. The internally mineralized cartilaginous skeleton in Palaeospondylus may represent a stage in the loss of bone characteristic of the Chondrichthyes.

  • 32.
    Karlson, Agnes M. L.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Reutgard, Martin
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Garbaras, Andrius
    Gorokhova, Elena
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Isotopic niche reflects stress-induced variability in physiological status2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 2, article id 171398Article in journal (Refereed)
    Abstract [en]

    The isotopic niche has become an established concept in trophic ecology. However, the assumptions behind this approach have rarely been evaluated. Evidence is accumulating that physiological stress can affect both magnitude and inter-individual variability of the isotopic signature in consumers via alterations in metabolic pathways. We hypothesized that stress factors (inadequate nutrition, parasite infestations, and exposure to toxic substances or varying oxygen conditions) might lead to suboptimal physiological performance and altered stable isotope signatures. The latter can be misinterpreted as alterations in isotopic niche. This hypothesis was tested by inducing physiological stress in the deposit-feeding amphipod Monoporeia affinis exposed to either different feeding regimes or contaminated sediments. In the amphipods, we measured body condition indices or reproductive output to assess growth status and delta C-13 and delta N-15 values to derive isotope niche metrics. As hypothesized, greater isotopic niche estimates were derived for the stressed animals compared to the control groups. Moreover, the delta N-15 values were influenced by body size, reproductive status and parasite infestations, while delta C-13 values were influenced by body size, oxygen conditions and survival. Using regression analysis with isotope composition and growth variables as predictors, we were able to discriminate between the amphipods exposed to nutritionally or chemically stressful conditions and those in the control groups. Thus, interpretation of isotopic niche can be confounded by natural or anthropogenic stressors that may induce an apparent change in isotopic niche. These findings stress the importance of including measures of growth and health status when evaluating stable isotope data in food web studies.

  • 33. Klein, E. S.
    et al.
    Barbier, M. R.
    Watson, James R.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Oregon State University, USA.
    The dual impact of ecology and management on social incentives in marine common-pool resource systems2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 8, article id 170740Article in journal (Refereed)
    Abstract [en]

    Understanding how and when cooperative human behaviour forms in common-pool resource systems is critical to illuminating social-ecological systems and designing governance institutions that promote sustainable resource use. Before assessing the full complexity of social dynamics, it is essential to understand, concretely and mechanistically, how resource dynamics and human actions interact to create incentives and pay-offs for social behaviours. Here, we investigated how such incentives for information sharing are affected by spatial dynamics and management in a common-pool resource system. Using interviews with fishermen to inform an agent-based model, we reveal generic mechanisms through which, for a given ecological setting characterized by the spatial dynamics of the resource, the two 'human factors' of information sharing and management may heterogeneously impact various members of a group for whom theory would otherwise predict the same strategy. When users can deplete the resource, these interactions are further affected by the management approach. Finally, we discuss the implications of alternative motivations, such as equity among fishermen and consistency of the fleet's output. Our results indicate that resource spatial dynamics, form of management and level of depletion can interact to alter the sociality of people in common-pool resource systems, providing necessary insight for future study of strategic decision processes.

  • 34.
    Koch, Franziska
    et al.
    School of Life Sciences, Institute for Chemistry and Bioanalytics, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland.
    Muller, Michael
    Department for Health Science and Technology, Cartilage Engineering and Regeneration Laboratory, ETH Zurich, Zurich, Switzerland.
    König, Finja
    Linköping University.
    Meyer, Nina
    Department for Chemistry and Biotechnology, Tissue Engineering, Zurich University of Applied Sciences, Wädenswil, Switzerland.
    Gattlen, Jasmin
    Department for Chemistry and Biotechnology, Tissue Engineering, Zurich University of Applied Sciences, Wädenswil, Switzerland.
    Pieles, Uwe
    School of Life Sciences, Institute for Chemistry and Bioanalytics, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland.
    Peters, Kirsten
    Department of Cell Biology, University Medicine Rostock, Rostock, Germany.
    Kreikemeyer, Bernd
    Institute of Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany.
    Mathes, Stephanie
    Department for Chemistry and Biotechnology, Tissue Engineering, Zurich University of Applied Sciences, Wädenswil, Switzerland.
    Saxer, Sina
    School of Life Sciences, Institute for Chemistry and Bioanalytics, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland.
    Mechanical characteristics of beta sheet-forming peptide hydrogels are dependent on peptide sequence, concentration and buffer composition2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 3, article id 171562Article in journal (Refereed)
    Abstract [en]

    Self-assembling peptide hydrogels can be modified regarding their biodegradability, their chemical and mechanical properties and their nanofibrillar structure. Thus, self assembling peptide hydrogels might be suitable scaffolds for regenerative therapies and tissue engineering. Owing to the use of various peptide concentrations and buffer compositions, the self-assembling peptide hydrogels might be influenced regarding their mechanical characteristics. Therefore, the mechanical properties and stability of a set of self-assembling peptide hydrogels, consisting of 11 amino acids, made from four beta sheet self-assembling peptides in various peptide concentrations and buffer compositions were studied. The formed self-assembling peptide hydrogels exhibited stiffnesses ranging from 0.6 to 205 kPa. The hydrogel stiffeness affected by peptide sequence followed by peptide concentration and buffer composition. All self-assembling peptide hydrogels examined provided a nanofibrillar network formation. A maximum self-assembling peptide hydrogel dissolution of 20% was observed for different buffers solution after 7 days. The stability regarding enzymatic and bacterial digestion showed less degradation in comparison to the self-assembling peptide hydrogel dissolution rate in buffer. The tested set of self-assembling peptide hydrogels were able to form stable scaffolds and provided a broad spectrum of tissue-specific stiffnesses that are suitable for a regenerative therapy.

  • 35.
    Kolipakam, Vishnupriya
    et al.
    Wildlife Inst India, Post Box 18, Dehra Dun 248001, Uttar Pradesh, India.;Max Planck Inst Psycholinguist, Evolutionary Proc Language & Culture, Wundtlaan 1, NL-6525 XD Nijmegen, Netherlands..
    Jordan, Fiona M.
    Max Planck Inst Psycholinguist, Evolutionary Proc Language & Culture, Wundtlaan 1, NL-6525 XD Nijmegen, Netherlands.;Univ Bristol, Dept Anthropol & Archaeol, 43 Woodland Rd, Bristol BS8 1UU, Avon, England.;Max Planck Inst Sci Human Hist, Dept Linguist & Cultural Evolut, Kahlaische Str 10, D-07745 Jena, Germany..
    Dunn, Michael
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Languages, Department of Linguistics and Philology. Max Planck Inst Psycholinguist, Evolutionary Proc Language & Culture, Wundtlaan 1, NL-6525 XD Nijmegen, Netherlands.
    Greenhill, Simon J.
    Max Planck Inst Sci Human Hist, Dept Linguist & Cultural Evolut, Kahlaische Str 10, D-07745 Jena, Germany.;Australian Natl Univ, ARC Ctr Excellence Dynam Language, Bldg 9,HC Coombs Bld, Canberra, ACT 2601, Australia..
    Bouckaert, Remco
    Max Planck Inst Sci Human Hist, Dept Linguist & Cultural Evolut, Kahlaische Str 10, D-07745 Jena, Germany.;Univ Auckland, Dept Comp Sci, 303-38 Princes St, Auckland 1010, New Zealand..
    Gray, Russell D.
    Max Planck Inst Sci Human Hist, Dept Linguist & Cultural Evolut, Kahlaische Str 10, D-07745 Jena, Germany..
    Verkerk, Annemarie
    Max Planck Inst Psycholinguist, Evolutionary Proc Language & Culture, Wundtlaan 1, NL-6525 XD Nijmegen, Netherlands.;Max Planck Inst Sci Human Hist, Dept Linguist & Cultural Evolut, Kahlaische Str 10, D-07745 Jena, Germany..
    A Bayesian phylogenetic study of the Dravidian language family2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 3, article id 171504Article in journal (Refereed)
    Abstract [en]

    The Dravidian language family consists of about 80 varieties (Hammarstrom H. 2016 Glottolog 2.7) spoken by 220 million people across southern and central India and surrounding countries (Steever SB. 1998 Tn The Dravidian languages (ed. SB Steever), pp. 1-39: 1). Neither the geographical origin of the Dravidian language homeland nor its exact dispersal through time are known. The history of these languages is crucial for understanding prehistory in Eurasia, because despite their current restricted range, these languages played a significant role in influencing other language groups including IndoAryan (Indo-European) and Munda (Austroasiatic) speakers. Here, we report the results of a Bayesian phylogenetic analysis of cognate -coded lexical data, elicited first hand from native speakers, to investigate the subgrouping of the Dravidian language family, and provide dates for the major points of diversification. Our results indicate that the Dravidian language family is approximately 4500 years old, a finding that corresponds well with earlier linguistic and archaeological studies. The main branches of the Dravidian language family (North, Central, South I, South II) are recovered, although the placement of languages within these main branches diverges from previous classifications. We find considerable uncertainty with regard to the relationships between the main branches.

  • 36.
    Lee, Marcus
    et al.
    Lund University, Sweden.
    Zhang, Huan
    Lund University, Sweden ; Chinese Academy of Sciences, China.
    Sha, Yongcui
    Lund University, Sweden.
    Hegg, Alexander
    Lund University, Sweden.
    Ugge, Gustaf Ekelund
    Lund University, Sweden.
    Vinterstare, Jerker
    Lund University, Sweden.
    Skerlep, Martin
    Lund University, Sweden.
    Parssinen, Varpu
    Lund University, Sweden.
    Herzog, Simon David
    Lund University, Sweden.
    Bjorneras, Caroline
    Lund University, Sweden.
    Gollnisch, Raphael
    Lund University, Sweden.
    Johansson, Emma
    Lund University, Sweden.
    Hu, Nan
    Lund University, Sweden.
    Nilsson, Per Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Lund University, Sweden.
    Hulthen, Kaj
    Lund University, Sweden ; North Carolina State University, USA.
    Rengefors, Karin
    Lund University, Sweden.
    Langerhans, R. Brian
    North Carolina State University, USA ; North Carolina State University, USA.
    Bronmark, Christer
    Lund University, Sweden.
    Hansson, Lars-Anders
    Lund University, Sweden.
    Low-latitude zooplankton pigmentation plasticity in response to multiple threats2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, p. 1-10, article id 190321Article in journal (Refereed)
    Abstract [en]

    Crustacean copepods in high-latitude lakes frequently alter their pigmentation facultatively to defend themselves against prevailing threats, such as solar ultraviolet radiation ( UVR) and visually oriented predators. Strong seasonality in those environments promotes phenotypic plasticity. To date, no one has investigated whether low-latitude copepods, experiencing continuous stress from UVR and predation threats, exhibit similar inducible defences. We here investigated the pigmentation levels of Bahamian 'blue hole' copepods, addressing this deficit. Examining several populations varying in predation risk, we found the lowest levels of pigmentation in the population experiencing the highest predation pressure. In a laboratory experiment, we found that, in contrast with our predictions, copepods from these relatively constant environments did show some changes in pigmentation subsequent to the removal of UVR; however, exposure to water from different predation regimes induced minor and idiosyncratic pigmentation change. Our findings suggest that low-latitude zooplankton in inland environments may exhibit reduced, but non-zero, levels of phenotypic plasticity compared with their high-latitude counterparts.

  • 37.
    Lind, Johan
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for Cultural Evolution.
    What can associative learning do for planning?2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 11, article id 180778Article in journal (Refereed)
    Abstract [en]

    There is a new associative learning paradox. The power of associative learning for producing flexible behaviour in non-human animals is downplayed or ignored by researchers in animal cognition, whereas artificial intelligence research shows that associative learning models can beat humans in chess. One phenomenon in which associative learning often is ruled out as an explanation for animal behaviour is flexible planning. However, planning studies have been criticized and questions have been raised regarding both methodological validity and interpretations of results. Due to the power of associative learning and the uncertainty of what causes planning behaviour in non-human animals, I explored what associative learning can do for planning. A previously published sequence learning model which combines Pavlovian and instrumental conditioning was used to simulate two planning studies, namely Mulcahy & Call 2006 'Apes save tools for future use.' Science 312, 1038-1040 and Kabadayi & Osvath 2017 'Ravens parallel great apes in flexible planning for tool-use and bartering. 'Science 357, 202-204. Simulations show that behaviour matching current definitions of flexible planning can emerge through associative learning. Through conditioned reinforcement, the learning model gives rise to planning behaviour by learning that a behaviour towards a current stimulus will produce high value food at a later stage; it can make decisions about future states not within current sensory scope. The simulations tracked key patterns both between and within studies. It is concluded that one cannot rule out that these studies of flexible planning in apes and corvids can be completely accounted for by associative learning. Future empirical studies of flexible planning in non-human animals can benefit from theoretical developments within artificial intelligence and animal learning.

  • 38.
    Lind, Johan
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology.
    Ghirlanda, Stefano
    Enquist, Magnus
    Stockholm University, Faculty of Science, Department of Zoology.
    Social learning through associative processes: a computational theory2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 3, article id 181777Article in journal (Refereed)
    Abstract [en]

    Social transmission of information is a key phenomenon in the evolution of behaviour and in the establishment of traditions and culture. The diversity of social learning phenomena has engendered a diverse terminology and numerous ideas about underlying learning mechanisms, at the same time that some researchers have called for a unitary analysis of social learning in terms of associative processes. Leveraging previous attempts and a recent computational formulation of associative learning, we analyse the following learning scenarios in some generality: learning responses to social stimuli, including learning to imitate; learning responses to non-social stimuli; learning sequences of actions; learning to avoid danger. We conceptualize social learning as situations in which stimuli that arise from other individuals have an important role in learning. This role is supported by genetic predispositions that either cause responses to social stimuli or enable social stimuli to reinforce specific responses. Simulations were performed using a new learning simulator program. The simulator is publicly available and can be used for further theoretical investigations and to guide empirical research of learning and behaviour. Our explorations show that, when guided by genetic predispositions, associative processes can give rise to a wide variety of social learning phenomena, such as stimulus and local enhancement, contextual imitation and simple production imitation, observational conditioning, and social and response facilitation. In addition, we clarify how associative mechanisms can result in transfer of information and behaviour from experienced to naive individuals.

  • 39.
    Linderholm, Anna
    et al.
    Univ Oxford, Res Lab Archaeol, Palaeogen & Bioarchaeol Res Network, Dyson Perrins Bldg,South Parks Rd, Oxford OX1 3QY, England.;Texas A&M Univ, Bioarchaeol & Genom Lab, Dept Anthropol, MS 4352 TAMU, College Stn, TX 77843 USA..
    Spencer, Daisy
    Univ Oxford, Res Lab Archaeol, Palaeogen & Bioarchaeol Res Network, Dyson Perrins Bldg,South Parks Rd, Oxford OX1 3QY, England.;Natl Univ Ireland, Discipline Archaeol, Univ Rd, Galway, Ireland..
    Battista, Vincent
    Univ Oxford, Res Lab Archaeol, Palaeogen & Bioarchaeol Res Network, Dyson Perrins Bldg,South Parks Rd, Oxford OX1 3QY, England..
    Frantz, Laurent
    Univ Oxford, Res Lab Archaeol, Palaeogen & Bioarchaeol Res Network, Dyson Perrins Bldg,South Parks Rd, Oxford OX1 3QY, England..
    Barnett, Ross
    Univ Oxford, Res Lab Archaeol, Palaeogen & Bioarchaeol Res Network, Dyson Perrins Bldg,South Parks Rd, Oxford OX1 3QY, England..
    Fleischer, Robert C.
    Smithsonian Conservat Biol Inst, Ctr Conservat Genom, Natl Zool Pk,MRC 5508, Washington, DC 20013 USA..
    James, Helen F.
    Smithsonian Inst, Natl Museum Nat Hist, Dept Vertebrate Zool, POB 37012, Washington, DC 20013 USA..
    Duffy, Dave
    Univ Hawaii Manoa, Dept Bot, 3190 MaileWay,Room 101, Honolulu, HI 96822 USA..
    Sparks, Jed P.
    Cornell Univ, Dept Ecol & Evolut, Ithaca, NY USA..
    Clements, David R.
    Trinity Western Univ, Dept Biol, Langley, BC V2Y 1Y1, Canada..
    Andersson, Leif
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Dobney, Keith
    Univ Liverpool, Dept Archaeol Class & Egyptol, 12-14 Abercromby Sq, Liverpool L69 7WZ, Merseyside, England..
    Leonard, Jennifer A.
    Estn Biol Donana EBD CSIC, Conservat & Evolutionary Genet Grp, Ave Amer Vespucio S-N, Seville 41092, Spain..
    Larson, Greger
    Univ Oxford, Res Lab Archaeol, Palaeogen & Bioarchaeol Res Network, Dyson Perrins Bldg,South Parks Rd, Oxford OX1 3QY, England..
    A novel MC1R allele for black coat colour reveals the Polynesian ancestry and hybridization patterns of Hawaiian feral pigs2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 9, article id 160304Article in journal (Refereed)
    Abstract [en]

    Pigs (Sus scrofa) have played an important cultural role in Hawaii since Polynesians first introduced them in approximately AD 1200. Additional varieties of pigs were introduced following Captain Cook's arrival in Hawaii in 1778 and it has been suggested that the current pig population may descend primarily, or even exclusively, from European pigs. Although populations of feral pigs today are an important source of recreational hunting on all of the major islands, they also negatively impact native plants and animals. As a result, understanding the origins of these feral pig populations has significant ramifications for discussions concerning conservation management, identity and cultural continuity on the islands. Here, we analysed a neutral mitochondrial marker and a functional nuclear coat colour marker in 57 feral Hawaiian pigs. Through the identification of a new mutation in the MC1R gene that results in black coloration, we demonstrate that Hawaiian feral pigs are mostly the descendants of those originally introduced during Polynesian settlement, though there is evidence for some admixture. As such, extant Hawaiian pigs represent a unique historical lineage that is not exclusively descended from feral pigs of European origin.

  • 40.
    Liuzza, Marco Tullio
    et al.
    Stockholm University.
    Lindholm, Torun
    Stockholm University.
    Hawley, Caitlin B.
    Stockholm University.
    Gustafsson Sendén, Marie
    Stockholm University.
    Ekström, Ingrid
    Stockholm University.
    Olsson, Mats J.
    Karolinska Institutet.
    Olofsson, Jonas K.
    Stockholm University.
    Body odour disgust sensitivity predicts authoritarian attitudes2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 2, article id 171091Article in journal (Refereed)
    Abstract [en]

    Authoritarianism has resurfaced as a research topic in political psychology, as it appears relevant to explain current political trends. Authoritarian attitudes have been consistently linked to feelings of disgust, an emotion that is thought to have evolved to protect the organism from contamination. We hypothesized that body odour disgust sensitivity (BODS) might be associated with authoritarianism, as chemo-signalling is a primitive system for regulating interpersonal contact and disease avoidance, which are key features also in authoritarianism. We used well-validated scales for measuring BODS, authoritarianism and related constructs. Across two studies, we found that BODS is positively related to authoritarianism. In a third study, we showed a positive association between BODS scores and support for Donald Trump, who, at the time of data collection, was a presidential candidate with an agenda described as resonating with authoritarian attitudes. Authoritarianism fully explained the positive association between BODS and support for Donald Trump. Our findings highlight body odour disgust as a new and promising domain in political psychology research. Authoritarianism and BODS might be part of the same disease avoidance framework, and our results contribute to the growing evidence that contemporary social attitudes might be rooted in basic sensory functions.

  • 41.
    Liuzza, Marco Tullio
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Personality, Social and Developmental Psychology. University of Catanzaro, Italy; University of Rome, Italy; RCCS Santa Lucia Foundation, Italy.
    Lindholm, Torun
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Personality, Social and Developmental Psychology.
    Hawley, Caitlin B.
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Gustafsson Sendén, Marie
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Personality, Social and Developmental Psychology.
    Ekström, Ingrid
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Olsson, Mats J.
    Olofsson, Jonas K.
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics. Swedish Collegium for Advanced Study, Sweden.
    Body odour disgust sensitivity predicts authoritarian attitudes2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 2, article id 171091Article in journal (Refereed)
    Abstract [en]

    Authoritarianism has resurfaced as a research topic in political psychology, as it appears relevant to explain current political trends. Authoritarian attitudes have been consistently linked to feelings of disgust, an emotion that is thought to have evolved to protect the organism from contamination. We hypothesized that body odour disgust sensitivity (BODS) might be associated with authoritarianism, as chemo-signalling is a primitive system for regulating interpersonal contact and disease avoidance, which are key features also in authoritarianism. We used well-validated scales for measuring BODS, authoritarianism and related constructs. Across two studies, we found that BODS is positively related to authoritarianism. In a third study, we showed a positive association between BODS scores and support for Donald Trump, who, at the time of data collection, was a presidential candidate with an agenda described as resonating with authoritarian attitudes. Authoritarianism fully explained the positive association between BODS and support for Donald Trump. Our findings highlight body odour disgust as a new and promising domain in political psychology research. Authoritarianism and BODS might be part of the same disease avoidance framework, and our results contribute to the growing evidence that contemporary social attitudes might be rooted in basic sensory functions.

  • 42.
    Marthin, Otte
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Damage shielding mechanisms in hierarchical composites in nature with potential for design of tougher structural materials2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 3, article id 181733Article in journal (Refereed)
    Abstract [en]

    Load-carrying materials in nature, such as wood and bone, consist of relatively simple building blocks assembled into a hierarchical structure, ranging from the molecular scale up to the macroscopic level. This results in composites with a combination of high strength and high toughness, showing very large fracture surfaces indicating energy dissipation by cracking on multiple length scales. Man-made composites instead consist typically of fibres embedded in a uniform matrix, and frequently show brittle failure through the growth of critical clusters of broken fibres. In this paper, a hierarchical structure inspired by wood is presented. It is designed to incapacitate cluster growth, with the aim of retaining high strength. This is done by introducing new structural levels of successively weaker interfaces with the purpose of reducing the stress concentrations if large clusters appear. To test this hypothesis, a probability density field of further damage growth has been calculated for different microstructures and initial crack sizes. The results indicate that the hierarchical structure should maintain its strength by localization of damage, yet rendering large clusters less harmful by weakening the resulting stress concentration to its surroundings, which would lead to an increase in strain to failure. In this context, the potential of using the biomimetic hierarchical structure in design of composite materials is discussed.

  • 43.
    Mendoza, Arturo
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. CINVESTAV, Mexico.
    Munoz-Pineda, Eloy
    CINVESTAV, Mexico.
    Järrendahl, Kenneth
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Pitch profile across the cuticle of the scarab beetle Cotinis mutabilis determined by analysis of Mueller matrix measurements2018In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 5, no 12, article id 181096Article in journal (Refereed)
    Abstract [en]

    Helicoidal structures of lamellae of nanofibrils constitute the cuticle of some scarab beetle; with iridescent metallic-like shine reflecting left-handed polarized light. The spectral and polarization properties of the reflected light depend on the pitch of the helicoidal structures, dispersion of effective refractive indices and thicknesses of layers in the cuticle. By modelling the outer exocuticle of the scarab beetle Cotinis mutabilis as a stack of continuously twisted biaxial slices of transparent materials, we extract optical and structural parameters by nonlinear regression analysis of variable-angle Mueller-matrix spectroscopic data. Inhomogeneities in the beetle cuticle produce depolarization with non-uniformity in cuticle thickness as the dominant effect. The pitch across the cuticle of C. mutabilis decreased with depth in a two-level profile from 380 to 335 nm and from 390 to 361 nm in greenish and reddish specimens, respectively, whereas in a yellowish specimen, the pitch decreased with depth in a three-level profile from 388 to 326 nm.

  • 44. Meyer, Kristina
    et al.
    Garzón, Benjamin
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Lövdén, Martin
    Stockholm University, Faculty of Social Sciences, Aging Research Center (ARC), (together with KI).
    Hildebrandt, Andrea
    Are global and specific interindividual differences in cortical thickness associated with facets of cognitive abilities, including face cognition?2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 180857Article in journal (Refereed)
    Abstract [en]

    Face cognition (FC) is a specific ability that cannot be fully explained by general cognitive functions. Cortical thickness (CT) is a neural correlate of performance and learning. In this registered report, we used data from the Human Connectome Project (HCP) to investigate the relationship between CT in the core brain network of FC and performance on a psychometric task battery, including tasks with facial content. Using structural equation modelling (SEM), we tested the existence of face-specific interindividual differences at behavioural and neural levels. The measurement models include general and face-specific factors of performance and CT. There was no face-specificity in CT in functionally localized areas. In post hoc analyses, we compared the preregistered, small regions of interest (ROIs) to larger, non-individualized ROIs and identified a face-specific CT factor when large ROIs were considered. We show that this was probably due to low reliability of CT in the functional localization (intra-class correlation coefficients (ICC) between 0.72 and 0.85). Furthermore, general cognitive ability, but not face-specific performance, could be predicted by latent factors of CT with a small effect size. In conclusion, for the core brain network of FC, we provide exploratory evidence (in need of cross-validation) that areas of the cortex sharing a functional purpose did also share morphological properties as measured by CT.

  • 45.
    Nilsonne, Gustav
    et al.
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Renberg, Adam
    Stockholm University, Faculty of Social Sciences, Stress Research Institute.
    Tamm, Sandra
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Lekander, Mats
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Health at the ballot box: disease threat does not predict attractiveness preference in British politicians2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, article id 160049Article in journal (Refereed)
    Abstract [en]

    According to disease avoidance theory, selective pressures have shaped adaptive behaviours to avoid people who might transmit infections. Such behavioural immune defence strategies may have social and societal consequences. Attractiveness is perceived as a heuristic cue of good health, and the relative importance of attractiveness is predicted to increase during high disease threat. Here, we investigated whether politicians' attractiveness is more important for electoral success when disease threat is high, in an effort to replicate earlier findings from the USA. We performed a cross-sectional study of 484 members of the House of Commons from England and Wales. Publicly available sexiness ratings (median 5883 ratings/politician) were regressed on measures of disease burden, operationalized as infant mortality, life expectancy and self-rated health. Infant mortality in parliamentary constituencies did not significantly predict sexiness of elected members of parliament (p = 0.08), nor did life expectancy (p = 0.06), nor self-rated health (p = 0.55). Subsample analyses failed to provide further support for the hypothesis. In conclusion, an attractive leader effect was not amplified by disease threat in the UK and these results did not replicate those of earlier studies from the USA concerning the relationship between attractiveness, disease threat and voting preference.

  • 46.
    Nilsonne, Gustav
    et al.
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Tamm, Sandra
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Golkar, Armita
    Sörman, Karolina
    Howner, Katarina
    Kristiansson, Marianne
    Olsson, Andreas
    Ingvar, Martin
    Petrovic, Predrag
    Effects of 25 mg oxazepam on emotional mimicry and empathy for pain: a randomized controlled experiment2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 3, article id 160607Article in journal (Refereed)
    Abstract [en]

    Emotional mimicry and empathy are mechanisms underlying social interaction. Benzodiazepines have been proposed to inhibit empathy and promote antisocial behaviour. First, we aimed to investigate the effects of oxazepam on emotional mimicry and empathy for pain, and second, we aimed to investigate the association of personality traits to emotional mimicry and empathy. Participants (n= 76) were randomized to 25mg oxazepam or placebo. Emotional mimicry was examined using video clips with emotional expressions. Empathy was investigated by pain stimulating the participant and a confederate. We recorded self-rated experience, activity in major zygomatic and superciliary corrugator muscles, skin conductance, and heart rate. In the mimicry experiment, oxazepam inhibited corrugator activity. In the empathy experiment, oxazepam caused increased self-rated unpleasantness and skin conductance. However, oxazepam specifically inhibited neither emotional mimicry nor empathy for pain. Responses in both experiments were associated with self-rated empathic, psychopathic and alexithymic traits. The present results do not support a specific effect of 25mg oxazepam on emotional mimicry or empathy.

  • 47.
    Nordström, Henrik
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Laukka, Petri
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Cognitive psychology.
    Thingujam, Nutankumar S.
    Schubert, Emery
    Elfenbein, Hillary Anger
    Emotion appraisal dimensions inferred from vocal expressions are consistent across cultures: a comparison between Australia and India2017In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 4, no 11, article id 170912Article in journal (Refereed)
    Abstract [en]

    This study explored the perception of emotion appraisal dimensions on the basis of speech prosody in a cross-cultural setting. Professional actors from Australia and India vocally portrayed different emotions (anger, fear, happiness, pride, relief, sadness, serenity and shame) by enacting emotion-eliciting situations. In a balanced design, participants from Australia and India then inferred aspects of the emotion-eliciting situation from the vocal expressions, described in terms of appraisal dimensions (novelty, intrinsic pleasantness, goal conduciveness, urgency, power and norm compatibility). Bayesian analyses showed that the perceived appraisal profiles for the vocally expressed emotions were generally consistent with predictions based on appraisal theories. Few group differences emerged, which suggests that the perceived appraisal profiles are largely universal. However, some differences between Australian and Indian participants were also evident, mainly for ratings of norm compatibility. The appraisal ratings were further correlated with a variety of acoustic measures in exploratory analyses, and inspection of the acoustic profiles suggested similarity across groups. In summary, results showed that listeners may infer several aspects of emotion-eliciting situations from the non-verbal aspects of a speaker's voice. These appraisal inferences also seem to be relatively independent of the cultural background of the listener and the speaker.

  • 48.
    Ollivier, Morgane
    et al.
    Ecole Normale Super Lyon, PALGENE, French Natl Platform Paleogenet, CNRS ENS Lyon, 46 Allee Italie, F-69364 Lyon 07, France.;Univ Grenoble Alpes, Lab Ecol Alpine LECA, F-38000 Grenoble, France..
    Tresset, Anne
    CNRS MNHN SUs UMR 7209, Archeozool Archeobot Soc Prat & Environm, 55 Rue Buffon, F-75005 Paris, France..
    Bastian, Fabiola
    Ecole Normale Super Lyon, PALGENE, French Natl Platform Paleogenet, CNRS ENS Lyon, 46 Allee Italie, F-69364 Lyon 07, France.;Univ Grenoble Alpes, Lab Ecol Alpine LECA, F-38000 Grenoble, France..
    Lagoutte, Laetitia
    Univ Rennes 1, CNRS UMR6290, Inst Genet & Dev Rennes, F-35000 Rennes, France..
    Axelsson, Erik
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Arendt, Maja Louise
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Balasescu, Adrian
    Natl Museum Romanian Hist, 12 Calea Victoriei, Bucharest 030026, Romania..
    Marshour, Marjan
    CNRS MNHN SUs UMR 7209, Archeozool Archeobot Soc Prat & Environm, 55 Rue Buffon, F-75005 Paris, France..
    Sablin, Mikhail V.
    Russian Acad Sci, Inst Zool, St Petersburg, Russia..
    Salanova, Laure
    CNRS ENS, Aoroc, 45 Rue Ulm, F-75005 Paris, France..
    Vigne, Jean-Denis
    Hitte, Christophe
    Univ Rennes 1, CNRS UMR6290, Inst Genet & Dev Rennes, F-35000 Rennes, France..
    Hanni, Catherine
    Ecole Normale Super Lyon, PALGENE, French Natl Platform Paleogenet, CNRS ENS Lyon, 46 Allee Italie, F-69364 Lyon 07, France.;Univ Grenoble Alpes, Lab Ecol Alpine LECA, F-38000 Grenoble, France..
    Amy2B copy number variation reveals starch diet adaptations in ancient European dogs2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 11, article id 160449Article in journal (Refereed)
    Abstract [en]

    Extant dog and wolf DNA indicates that dog domestication was accompanied by the selection of a series of duplications on the Amy2B gene coding for pancreatic amylase. In this study, we used a palaeogenetic approach to investigate the timing and expansion of the Amy2B gene in the ancient dog populations of Western and Eastern Europe and Southwest Asia. Quantitative polymerase chain reaction was used to estimate the copy numbers of this gene for 13 ancient dog samples, dated to between 15 000 and 4000 years before present (cal. BP). This evidenced an increase of Amy2B copies in ancient dogs from as early as the 7th millennium cal. BP in Southeastern Europe. We found that the gene expansion was not fixed across all dogs within this early farming context, with ancient dogs bearing between 2 and 20 diploid copies of the gene. The results also suggested that selection for the increased Amy2B copy number started 7000 years cal. BP, at the latest. This expansion reflects a local adaptation that allowed dogs to thrive on a starch rich diet, especially within early farming societies, and suggests a biocultural coevolution of dog genes and human culture.

  • 49.
    Pardo-Perez, Judith M.
    et al.
    Staatliches Museum Nat Kunde, Stuttgart, Germany;Univ Magallanes, Direcc Invest & Postgrad, Punta Arenas, Chile.
    Kear, Benjamin P.
    Uppsala University, Music and Museums, Museum of Evolution. Uppsala Univ, Museum Evolut, Uppsala, Sweden.
    Maxwell, Erin E.
    Staatliches Museum Nat Kunde, Stuttgart, Germany.
    Palaeoepidemiology in extinct vertebrate populations: factors influencing skeletal health in Jurassic marine reptiles2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 190264Article in journal (Refereed)
    Abstract [en]

    Palaeoepidemiological studies related to palaeoecology are rare, but have the potential to provide information regarding ecosystem-level characteristics by measuring individual health. In order to assess factors underlying the prevalence of pathologies in large marine vertebrates, we surveyed ichthyosaurs (Mesozoic marine reptiles) from the Posidonienschiefer Formation (Early Jurassic: Toarcian) of southwestern Germany. This Formation provides a relatively large sample from a geologically and geographically restricted interval, making it ideal for generating baseline data for a palaeoepidemiological survey. We examined the influence of taxon, anatomical region, body size, ontogeny and environmental change, as represented by the early Toarcian Oceanic Anoxic Event, on the prevalence of pathologies, based on a priori ideas of factors influencing population skeletal health. Our results show that the incidence of pathologies is dependent on taxon, with the small-bodied genus Stenopterygius exhibiting fewer skeletal pathologies than other genera. Within Stenopterygius, we detected more pathologies in large adults than in smaller size classes. Stratigraphic horizon, a proxy for palaeoenvironmental change, did not influence the incidence of pathologies in Stenopterygius. The quantification of the occurrence of pathologies within taxa and across guilds is critical to constructing more detailed hypotheses regarding changes in the prevalence of skeletal injury and disease through Earth history.

  • 50.
    Qvarnström, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Vikberg Wernström, Joel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology.
    Piechowski, Rafal
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland;Univ Warsaw, Dept Palaeobiol & Evolut, Fac Biol, Biol & Chem Res Ctr, Zwirki & Wigury 101, PL-02089 Warsaw, Poland.
    Talanda, Mateusz
    Univ Warsaw, Dept Palaeobiol & Evolut, Fac Biol, Biol & Chem Res Ctr, Zwirki & Wigury 101, PL-02089 Warsaw, Poland.
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Beetle-bearing coprolites possibly reveal the diet of a Late Triassic dinosauriform2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 3, article id 181042Article in journal (Refereed)
    Abstract [en]

    Diets of extinct animals can be difficult to analyse if no direct evidence, such as gut contents, is preserved in association with body fossils. Inclusions from coprolites (fossil faeces), however, may also reflect the diet of the host animal and become especially informative if the coprolite producer link can be established. Here we describe, based on propagation phase-contrast synchrotron microtomography (PPC-SRμCT), the contents of five morphologically similar coprolites collected from two fossil-bearing intervals from the highly fossiliferous Upper Triassic locality at Krasiejow in Silesia, Poland. Beetle remains, mostly elytra, and unidentified exoskeleton fragments of arthropods are the most conspicuous inclusions found in the coprolites. The abundance of these inclusions suggests that the coprolite producer deliberately targeted beetles and similar small terrestrial invertebrates as prey, but the relatively large size of the coprolites shows that it was not itself a small animal. The best candidate from the body fossil record of the locality is the dinosauriform Silesaurus opolensis Dzik, 2003, which had an anatomy in several ways similar to those of bird-like neotheropod dinosaurs and modern birds. We hypothesize that the beak-like jaws of S. opolensis were used to efficiently peck small insects off the ground, a feeding behaviour analogous to some extant birds.

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