95 research outputs found

    Sexual Differences in Chimpanzee Sociality

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    Scientists usually attribute sexual differences in sociality to sex-specific dispersal patterns and the availability of kin within the social group. In most primates, the dispersing sex, which has fewer kin around, is the less social sex. Chimpanzees fit well into the pattern, with highly social philopatric males and generally solitary dispersing females. However, researchers in West Africa have long suggested that female chimpanzees can be highly social. We investigated whether chimpanzees in the Taï Forest (Côte d’Ivoire) exhibit the expected sexual differences in 3 social parameters: dyadic association, party composition, and grooming interactions. Though we found a significant sexual difference in each of the 3 parameters, with males being more social than females, the actual values do not reveal striking differences between the sexes and do not support the notion of female chimpanzees as asocial: females had dyadic association indices comparable to mixed-sex dyads, spent ca. 82% of their time together with other adult chimpanzees, and had a comparable number of grooming partners. Further, female associations can be among the strongest bonds within the community, indicating that both sexes can have strongly favored association partners. The findings are in contrast to reports on East African chimpanzees, the females of which are mainly solitary and rarely interact with other females. Our results suggest that researchers cannot generally regard chimpanzee females as asocial and need to redefine models deriving patterns of sociality from dispersal patterns to integrate the possibility of high female sociality in male philopatric systems

    Estrogen Receptor β-Selective Agonists Stimulate Calcium Oscillations in Human and Mouse Embryonic Stem Cell-Derived Neurons

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    Estrogens are used extensively to treat hot flashes in menopausal women. Some of the beneficial effects of estrogens in hormone therapy on the brain might be due to nongenomic effects in neurons such as the rapid stimulation of calcium oscillations. Most studies have examined the nongenomic effects of estrogen receptors (ER) in primary neurons or brain slices from the rodent brain. However, these cells can not be maintained continuously in culture because neurons are post-mitotic. Neurons derived from embryonic stem cells could be a potential continuous, cell-based model to study nongenomic actions of estrogens in neurons if they are responsive to estrogens after differentiation. In this study ER-subtype specific estrogens were used to examine the role of ERα and ERβ on calcium oscillations in neurons derived from human (hES) and mouse embryonic stem cells. Unlike the undifferentiated hES cells the differentiated cells expressed neuronal markers, ERβ, but not ERα. The non-selective ER agonist 17β-estradiol (E2) rapidly increased [Ca2+]i oscillations and synchronizations within a few minutes. No change in calcium oscillations was observed with the selective ERα agonist 4,4′,4″-(4-Propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol (PPT). In contrast, the selective ERβ agonists, 2,3-bis(4-Hydroxyphenyl)-propionitrile (DPN), MF101, and 2-(3-fluoro-4-hydroxyphenyl)-7-vinyl-1,3 benzoxazol-5-ol (ERB-041; WAY-202041) stimulated calcium oscillations similar to E2. The ERβ agonists also increased calcium oscillations and phosphorylated PKC, AKT and ERK1/2 in neurons derived from mouse ES cells, which was inhibited by nifedipine demonstrating that ERβ activates L-type voltage gated calcium channels to regulate neuronal activity. Our results demonstrate that ERβ signaling regulates nongenomic pathways in neurons derived from ES cells, and suggest that these cells might be useful to study the nongenomic mechanisms of estrogenic compounds

    Reaping the benefits of digitisation:Pilot study exploring revenue generation from digitised collections through technological Innovation

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    In the last decade significant resources have been invested for the digitisation of the collections of a large number of museums and galleries worldwide. In Europe alone, 10 million EUR is annually invested in Europeana (Europeana 2014). However, as we gradually move on from “the start-up phase” of digitisation (Hughes 2004), revenue generation and sustainability must be considered (Hughes 2004). Even beyond digitisation, generating revenue through innovation and in particular “finding new business models to sustain funding” (Simon 2011) ranks amongst museums’ top challenges (Simon 2011). More importantly, despite the significant wealth of digitised assets museums now own, little has been done to investigate ways these institutions could financially benefit from their digitised collections. For art institutions in particular, this has been largely limited to the sale of image licenses, with the fear of losing this revenue posing as one of the key reasons art museums are reluctant to join the Open Content movement (Kapsalis 2016). This paper examines how recent technological advancements, such as image recognition and Print-on-Demand automation, can be utilised to take advantage of the wealth of digitised artworks museums and galleries have in their possession. A pilot study of the proposed solution at the State Museum of Contemporary Art (SMCA) in Thessaloniki, Greece, is covered and the findings are examined. Early feedback indicates that there is a significant potential in the utilisation of the aforementioned technologies for the monetisation of digitised collections. However, challenges such as blending the real-world experience with the digital experience, as well as flattening the learning curve of the technological solution for museum visitors, need to be addressed. Based on the pilot study at SMCA, this paper investigates how emerging technologies can be utilised to facilitate revenue generation for all museums and galleries with digitised collections

    An Individual-Oriented Model on the Emergence of Support in Fights, Its Reciprocation and Exchange

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    Complex social behaviour of primates has usually been attributed to the operation of complex cognition. Recently, models have shown that constraints imposed by the socio-spatial structuring of individuals in a group may result in an unexpectedly high number of patterns of complex social behaviour, resembling the dominance styles of egalitarian and despotic species of macaques and the differences between them. This includes affiliative patterns, such as reciprocation of grooming, grooming up the hierarchy, and reconciliation. In the present study, we show that the distribution of support in fights, which is the social behaviour that is potentially most sophisticated in terms of cognitive processes, may emerge in the same way. The model represents the spatial grouping of individuals and their social behaviour, such as their avoidance of risks during attacks, the self-reinforcing effects of winning and losing their fights, their tendency to join in fights of others that are close by (social facilitation), their tendency to groom when they are anxious, the reduction of their anxiety by grooming, and the increase of anxiety when involved in aggression. Further, we represent the difference in intensity of aggression apparent in egalitarian and despotic macaques. The model reproduces many aspects of support in fights, such as its different types, namely, conservative, bridging and revolutionary, patterns of choice of coalition partners attributed to triadic awareness, those of reciprocation of support and ‘spiteful acts’ and of exchange between support and grooming. This work is important because it suggests that behaviour that seems to result from sophisticated cognition may be a side-effect of spatial structure and dominance interactions and it shows that partial correlations fail to completely omit these effects of spatial structure. Further, the model is falsifiable, since it results in many patterns that can easily be tested in real primates by means of existing data

    Cooperation, coalition and alliances

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    Social Bonding and Nurture Kinship: Compatibility between Cultural and Biological Approaches

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    Cooperation, coalition, alliances

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    Idea: Efficient Evaluation of Access Control Constraints

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    Abstract Business requirements for modern enterprise systems usually comprise a variety of dynamic constraints, i. e., constraints that require a complex set of context information only available at runtime. Thus, the efficient evaluation of dynamic constraints, e. g., expressing separation of duties requirements, becomes an important factor for the overall performance of the access control enforcement. In distributed systems, e. g., based on the service-oriented architecture (SOA), the time for evaluating access control constraints depends significantly on the protocol between the central Policy Decision Point (PDP) and the distributed Policy Enforcement Points (PEPs). In this paper, we present a policy-driven approach for generating customized protocol for the communication between the PDP and the PEPs. We provide a detailed comparison of several approaches for querying context information during the evaluation of access control constraints. Key words: distributed policy enforcement, XACML, access control
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