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Norm shifts under the strategy method
Get PDFThe strategy method is a powerful method for eliciting conditional cooperation in strategic interactions. Theoretically, players’ cooperation conditional on a specific level of others’ cooperation using the strategy method should be equal to their unconditional cooperation given an equivalent belief about others’ cooperation. However, using the Prisoner’s Dilemma, we show that decisions using the strategy method are more selfish than decisions under a simultaneous decision protocol predicted from players’ beliefs. This is driven entirely by lower cooperation among conditional cooperators with low expectations about others’ cooperation. We further show that relative to simultaneous choice, the strategy method shifts salient norms from an egalitarian fairness norm (‘give half’) to a reciprocity norm (‘match others’ behaviour’). This undermines cooperation among players with low beliefs about others’ cooperation. These results thus show that the strategy method does not merely hold beliefs constant, but also shifts which salient norms influence choice behaviour. This has important implications for the use of the strategy method in eliciting social preferences.Peer reviewe
Mechanism of kisspeptin neuron synchronization for pulsatile hormone secretion in male mice
Get PDFFunding: This work was supported by the Wellcome Trust (212242/Z/18/Z) and the New Zealand Health Research Council (16-148). J.-C.K. received a Doc.Mobility fellowship (P1ZHP1_184166) from the Swiss National Science Foundation.The mechanism by which arcuate nucleus kisspeptin (ARNKISS) neurons co-expressing glutamate, neurokinin B, and dynorphin intermittently synchronize their activity to generate pulsatile hormone secretion remains unknown. An acute brain slice preparation maintaining synchronized ARNKISS neuron burst firing was used alongside in vivo GCaMP GRIN lens microendoscope and fiber photometry imaging coupled with intra-ARN microinfusion. Studies in intact and gonadectomized male mice revealed that ARNKISS neuron synchronizations result from near-random emergent network activity within the population and that this was critically dependent on local glutamate-AMPA signaling. Whereas neurokinin B operated to potentiate glutamate-generated synchronizations, dynorphin-kappa opioid tone within the network served as a gate for synchronization initiation. These observations force a departure from the existing "KNDy hypothesis" for ARNKISS neuron synchronization. A "glutamate two-transition" mechanism is proposed to underlie synchronizations in this key hypothalamic central pattern generator driving mammalian fertility.Peer reviewe
Where the wild bees are : birds improve indicators of bee richness
Get PDFFunding: The research included in this paper was made possible through funding by the Walmart Foundation to JR, AR, and AJ.Widespread declines in wild bee populations necessitate urgent action, but insufficient data exist to guide conservation efforts. Addressing this data deficit, we investigated the relative performance of environmental and/or taxon-based indicators to predict wild bee richness in the eastern and central U.S. Our methodology leveraged publicly available data on bees (SCAN and GBIF data repositories), birds (eBird participatory science project) and land cover data (USDA Cropland Data Layer). We used a Bayesian variable selection algorithm to select variables that best predicted species richness of bees using two datasets: a semi-structured dataset covering a wide geographical and temporal range and a structured dataset covering a focused extent with a standardized protocol. We demonstrate that birds add value to land cover data as indicators of wild bee species richness across broad geographies, particularly when using semi-structured data. These improvements likely stem from the demonstrated sensitivity of birds to conditions thought to impact bees but that are missed by remotely sensed environmental data. Importantly, this enables estimation of bee richness in places that don’t have direct observations of bees. In the case of wild bees specifically, we suggest that bird and land cover data, when combined, serve as useful indicators to guide monitoring and conservation priorities until the quality and quantity of bee data improve.Peer reviewe
‘All possible devotion to poetry and beauty’ : comparative interpretations of the archetypal female character in early British narrative photography
No full textEarly British narrative photographs of sitters dressed as archetypal characters from literature, poetry, history and mythology have until now been seen primarily as unsuccessful anomalies in the oeuvres of well-known art photographers like Julia Margaret Cameron and Oscar G. Rejlander. Far from being awkward and infrequent aberrations, I argue these images were part of a wider experimental genre, which I am calling “fictive portraiture,” and were created by early photographers to reconcile their work with ‘High Art’ at a time when photography was rarely seen as an art in its own right.
In this thesis, I examine social networks of artists and other creatives surrounding these images, placing the work of lesser-known photographers such as Lady Alice Kerr, E. P. Ogier, and William Despard Hemphill in context with well-known photographers like Cameron and Rejlander. I argue that rather than working in isolation, photographers undertaking fictive portraiture were often connected, collaborative, and inspired by each other’s work and concurrent art movements such as Pre-Raphaelitism.
The majority of popular fictive portraiture subjects were archetypal female characters. Through three case studies, I examine how the archetypal characters of Rachel, Rebecca, and Ruth from the Old Testament in the traditional role of Matriarch, Joan of Arc and Judith of Bethulia in the nontraditional role of Female Patriot, and Elaine of Astolat and the Lady of Shalott in the vulnerability of Female Death not only reflect the wealthy Victorian world view, but can offer insight into the cultural moments in which these photographs were made. I also explore how portrayal of these women through fictive portraiture not only reflected Victorian societal expectations of middle- and upper-class women, but also how differences in portrayals of the same characters by male and female photographers lends insight into different interpretations of women’s expected roles."This thesis and parallel research, engagement, and publication activities were supported by the University of St Andrews (School of Art History), the University of St Andrews International Student Discretionary Fund, the British Association for Victorian Studies Funding Grant scheme, Scottish Graduate School for Arts and Humanities Doctoral Internship scheme in partnership with Edinburgh Printmakers, the Society for the Study of Nineteenth Century Ireland Conference Bursary Fund, and the Association for Art History Scholarly Research Grant scheme."--Fundin
The housing integration of refugees and asylum seekers in Germany
Get PDFFunding: This work is funded by the MigrantLife project which received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 834103).In recent years, refugee migrants have become a significant population in many European countries, yet little is known about their housing market integration post-arrival. Our study, using data from the German Socio-Economic Panel (GSOEP), examines the residential mobility and homeownership of refugees, asylum seekers, and other immigrants. Analyzing housing trajectories for refugees from Syria, Afghanistan, and Iraq, we consider time-varying partnership and employment status, along with their duration of stay. We find that refugees initially exhibit higher mobility rates when compared to other immigrant groups. However, their mobility rates become similar to those of other groups after five years of residence. Refugees are consistently more likely to move into government housing and less likely to transition into homeownership compared to other groups, irrespective of their duration of stay. The results highlight the housing insecurity faced by refugee migrants, providing valuable insights into their unique challenges within the housing market.Peer reviewe
North American bird declines are greatest where species are most abundant
Get PDFFunding: This work was supported by the Leon Levy Foundation (D.F.), the Wolf Creek Foundation, and the National Science Foundation DBI-1939187 (C.L.W., D.F.). Computing support from the National Science Foundation was provided through CNS-1059284 and CCF-1522054. This work used Bridges2 at Pittsburgh Supercomputing Center and Anvil (45) at the Rosen Center for Advanced Computing at Purdue University through allocation DEB200010 (D.F., T.A., S.L., O.R.) from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, which is supported by NSF grants 2138259, 2138286, 2138307, 2137603, and 2138296.Efforts to address declines of North American birds have been constrained by limited availability of fine-scale information about population change. By using participatory science data from eBird, we estimated continental population change and relative abundance at 27-kilometer resolution for 495 bird species from 2007 to 2021. Results revealed high and previously undetected spatial heterogeneity in trends; although 75% of species were declining, 97% of species showed separate areas of significantly increasing and decreasing populations. Populations tended to decline most steeply in strongholds where species were most abundant, yet they fared better where species were least abundant. These high-resolution trends improve our ability to understand population dynamics, prioritize recovery efforts, and guide conservation at a time when action is urgently needed.Peer reviewe
Demonstration of a 650 °C operating high-performance metal-supported solid oxide fuel cell using a Gd-doped CeO2 electrolyte, Ni anode and Sm(Ba0.5Sr0.5)Co2−xFexO5+δ-Ce0.9Gd0.1O2−δ cathode
Get PDFFunding: This research was financially supported by the National key research and development program of China (No. 2021YFB4001400) and key research and development projects of Shaanxi Province (S2023-YF-LLRH-QCYK-0201). This work was supported by the Xi'an Advanced Functional Coating Technology International Science and Technology Cooperation Base. V. T. thanks the University of St Andrews for Chair in Energy and F. L. thanks CSC for the graduate scholarship for visiting St Andrews.Metal-supported solid oxide fuel cells (MS-SOFCs) exhibit numerous advantages, including thermal cycle stability, rapid start-up and lower costs. However, the slow oxygen reduction reaction (ORR) at the cathode, especially at intermediate-low temperatures, poses a critical challenge to the development of MS-SOFCs. Herein, we report a synergistic effect of co-doping in a cation-ordered double perovskite-type material, Sm(Ba0.5Sr0.5)Co2−xFexO5+δ (SBSCFx), which has enhanced catalytic activity for ORR and chemical compatibility with Ce0.9Gd0.1O2−δ (GDC). X-ray photoelectron spectroscopy and thermogravimetric analysis were used to examine how Fe-doping in SBSCFx impacts the functional properties. A composite cathode with GDC was further prepared to enhance thermal compatibility with GDC, which effectively reduces the thermal expansion of the SBSCFx cathode from 23.35 × 10−6 K−1 to 15.04 × 10−6 K−1. The electrochemical results of symmetrical cells and the DRT fitting analysis demonstrate that the SBSCFx-GDC composite cathode exhibits strong ORR activity. Notably, the SBSCF10-GDC composite cathode achieves a remarkably low polarization resistance of 0.05 Ω cm2 at 650 °C. The metal-supported single cell with the SBSCF10-GDC cathode exhibited an open-circuit voltage of 0.85 V and showed a peak power density of 833 mW cm−2 at 650 °C. Furthermore, its stability during long-term cell operation highlights its potential as a cathode for intermediate-low temperature metal-supported SOFCs.Peer reviewe
Shifting GnRH neuron ensembles underlie successive preovulatory luteinizing hormone surges
Get PDFFunding: This work was supported by the Wellcome Trust (212242/Z/18/Z).The gonadotropin-releasing hormone (GnRH) neurons operate as a neuronal ensemble exhibiting coordinated activity once every reproductive cycle to generate the preovulatory GnRH surge. Using GCaMP fiber photometry at the GnRH neuron distal dendrons to measure the output of this widely scattered population in female mice, we find that the onset, amplitude, and profile of GnRH neuron surge activity exhibits substantial variability from cycle to cycle both between and within individual mice. This was also evident when measuring successive proestrous luteinizing hormone surges. Studies combining short (c-Fos and c-Jun) and long (genetic robust activity marking) term indices of immediate early gene activation revealed that, while ∼50% of GnRH neurons were activated at the time of each surge, only half of these neurons had been active during the previous proestrous surge. These observations reveal marked inter- and intra-individual variability in the GnRH surge mechanism. Remarkably, different subpopulations of overlapping GnRH neurons are recruited to the ensemble each estrous cycle to generate the GnRH surge. While engendering variability in the surge mechanism itself, this likely provides substantial robustness to a key event underlying mammalian reproduction.Peer reviewe
Anthropocene Mobilities in contemporary art : exploring a movement-oriented lens in times of ecological crisis
No full textAbstract redacted"This research was supported by the Elizabeth Gilmore Holt Scholarship, the Russell Award, St Leonard’s Postgraduate College, and the Santander Mobility Award."--Fundin
Hubble's Variable Nebula I : ripples on a big screen
Get PDFNGC 2261 is a reflection nebula illuminated by the young star R Monocerotis. Objects moving near the star occasionally cast shadows on the nebula, giving rise to its alternative name: Hubble’s Variable Nebula. For 7 yr since Spring 2017 robotic telescopes have been used to compile a roughly twice-weekly record of changes in the object. The results, over 1000 images at separate epochs, have been compiled into a movie. This shows that, as well as the large scale but infrequent variability for which it is famous, the nebula is continually traversed by low level ‘ripples’ of light and dark. These record changes in the light output from R Mon and analysis of their progress indicates that the reflecting material takes the form of a thin ( 1.7 × 105 cm−3 and CO observations show the material is moving towards us at a few km s−1 relative to the rest cloud, consistent it with being a dense shell of material displaced by R Mon’s outflow. The results demonstrate the value of studying such objects in the time domain, and are a glimpse of what will be achieved by instruments like the Zwicky Transient Facility and Vera Rubin Observatory.Peer reviewe
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