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Previous reproductive success informs nest-building decisions
Get PDFBehavioral outcomes, including foraging efficiency and reproductive success, often improve with age and with repeated breeding attempts. Here we examined the role of previous experience on the nest-building behavior of wild blue tits Cyanistes caeruleus. In particular, we focused on how previous success or failure in rearing nestlings shapes nest-building decisions in subsequent years. We found that previous breeding outcome is important for predicting nest building decisions in blue tits: birds that had previously raised fledglings added insulating material at a similar rate as they had when they built their first nest. Some birds that had been previously unsuccessful changed their rate of adding insulating material and then were more likely to produce fledglings. These responses indicate that at least some of the decisions made by wild nest-building birds are based on their own experience of past breeding seasons.Peer reviewe
New chemistry of Sn-based negative electrodes for Na-ion batteries
No full textLithium-ion batteries (LIBs) dominate the market due to their high power and energy density. However, concerns regarding the scarcity of raw materials have prompted the scientific community to explore alternatives. Sodium-ion batteries (NIBs) have emerged as a promising alternative, owing to their abundance and cost-effectiveness. Tin and tin-based materials are particularly attractive for NIBs, given their high specific capacity (847 mAh g⁻¹ for Na₁₅Sn₄), natural abundance, and low operating voltage. Despite advances in understanding the mechanisms and developing advanced materials for next-generation NIBs, challenges such as poor electronic conductivity, significant volume expansion, and low initial coulombic efficiency (ICE) persist.
This work aims to develop a comprehensive understanding of tin’s electrochemical properties through a comparative study of in-house synthesised tin and commercial micron-sized tin. Tin particles, ranging from ≈50 nm to ≈1 µm, were synthesised via a chemical reduction method and examined under two electrolytes: 1M NaPF₆ in EC:DEC and diglyme, given the known degradation of carbonates in the presence of tin metal. Ex-situ SEM and EDS analyses were employed to assess the impact of these electrolytes on cycling performance, revealing key issues of significant volume expansion (up to 430%) due to NaSn to Na₁₅Sn₄ alloy formation and incompatibility with carbonate-based electrolytes.
To address these issues, the introduction of buffer matrices such as Na₄P₂O₇ or Na₃(PO₄) was explored. It was found that the in-situ carbon-composite SnP₂O₇ delivered the best electrochemical performance, achieving a reversible capacity of 300 mAh g⁻¹ over 200 cycles, Additionally, the poor ICE was mitigated by using 1M Na-biphenyl, which improved the ICE to ≈100%.
Further investigation into NaSn₂(PO₄)₃, a NASICON-type material with high Na-ion conductivity, demonstrate that amorphous NaSn₂(PO₄)₃ materials effectively accommodated volume expansion and exhibited enhanced cycle life compared to their pristine and carbon-coated counterparts, underscoring its potential as a viable electrode material for NIBs."This work was supported by the Faraday Institution NEXGENNA project [FIRG018] and the University of St Andrews [School of Chemistry]."--Fundin
Performance characteristics of a novel 3D-printed bubble intermittent mandatory ventilator (B-IMV) for adult pulmonary support
Get PDFFunding: Funding for this research was provided by a grant from The University of Chicago Healthcare Delivery Science and Innovation Fund and Seattle Children’s Research Institute.The COVID-19 pandemic has brought attention to the need for developing effective respiratory support that can be rapidly implemented during critical surge capacity scenarios in healthcare settings. Lung support with bubble continuous positive airway pressure (B-CPAP) is a well-established therapeutic approach for supporting neonatal patients. However, the effectiveness of B-CPAP in larger pediatric and adult patients has not been addressed. Using similar principles of B-CPAP pressure generation, application of intermittent positive pressure inflations above CPAP could support gas exchange and high work of breathing levels in larger patients experiencing more severe forms of respiratory failure. This report describes the design and performance characteristics of the BubbleVent, a novel 3D-printed valve system that combined with commonly found tubes, hoses, and connectors can provide intermittent mandatory ventilation (IMV) suitable for adult mechanical ventilation without direct electrification. Testing of the BubbleVent was performed on a passive adult test lung model and compared with a critical care ventilator commonly used in tertiary care centers. The BubbleVent was shown to deliver stable PIP and PEEP levels, as well as timing control of breath delivery that was comparable with a critical care ventilator.Peer reviewe
Geothermal stickleback populations prefer cool water despite multigenerational exposure to a warm environment
Get PDFFunding: Natural Environment Research Council, Grant/Award Number: NE/N016734/1.Given the threat of climate change to biodiversity, a growing number of studies are investigating the potential for organisms to adapt to rising temperatures. Earlier work has predicted that physiological adaptation to climate change will be accompanied by a shift in temperature preferences, but empirical evidence for this is lacking. Here, we test whether exposure to different thermal environments has led to changes in preferred temperatures in the wild. Our study takes advantage of a “natural experiment” in Iceland, where freshwater populations of threespine sticklebacks (Gasterosteus aculeatus) are found in waters warmed by geothermal activity year-round (warm habitats), adjacent to populations in ambient-temperature lakes (cold habitats). We used a shuttle-box approach to measure temperature preferences of wild-caught sticklebacks from three warm–cold population pairs. Our prediction was that fish from warm habitats would prefer higher water temperatures than those from cold habitats. We found no support for this, as fish from both warm and cold habitats had an average preferred temperature of 13°C. Thus, our results challenge the assumption that there will be a shift in ectotherm temperature preferences in response to climate change. In addition, since warm-habitat fish can persist at relatively high temperatures despite a lower-temperature preference, we suggest that preferred temperature alone may be a poor indicator of a population's adaptive potential to a novel thermal environment.Peer reviewe
Dynamic crystallography reveals spontaneous anisotropy in cubic GeTe
Get PDFFunding: The authors thank the European Synchrotron Radiation Facility for the provision of beamline time on ID15B and ID31. This research used resources at the Spallation Neutron Source, a US Department of Energy (DOE), Office of Science User Facility, operated by the Oak Ridge National Laboratory. The computing and software resources were made available through the VirtuES and the ICEMAN projects, funded by the Laboratory Directed Research and Development program (LDRDs 7739, 8237,10447) and Compute and Data Environment for Science (CADES) at the Oak Ridge National Laboratory, which is supported by the Office of Science of the DOE under Contract DE-AC05-00OR22725. S.J.L.B. acknowledges support from the US DOE, Office of Science, Office of Basic Energy Sciences, under contract no. DE- SC0012704. C.H.L. acknowledges support from NSF GRFP DGE-1746045. G.G.G.-V. acknowledges support from the Vice-Rector for Research at the University of Costa Rica (project no. 816-C1-601). Work at Argonne (P.B.L.) is supported by the US DOE, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering, under contract no. DE-AC02-06CH11357. At Northwestern University (M.G.K.), work on thermoelectric materials is primarily supported by the US DOE, Office of Science, Office of Basic Energy Sciences, under award no. DE-SC0014520. This work was supported by the Programme of Investments for the Future, an ISITE-BFC project (contract no. ANR-15-IDEX-0003) (S.A.J.K.).Cubic energy materials such as thermoelectrics or hybrid perovskite materials are often understood to be highly disordered. In GeTe and related IV–VI compounds, this is thought to provide the low thermal conductivities needed for thermoelectric applications. Since conventional crystallography cannot distinguish between static disorder and atomic motions, we develop the energy-resolved variable-shutter pair distribution function technique. This collects structural snapshots with varying exposure times, on timescales relevant for atomic motions. In disagreement with previous interpretations, we find the time-averaged structure of GeTe to be crystalline at all temperatures, but with anisotropic anharmonic dynamics at higher temperatures that resemble static disorder at fast shutter speeds, with correlated ferroelectric fluctuations along the c direction. We show that this anisotropy naturally emerges from a Ginzburg–Landau model that couples polarization fluctuations through long-range elastic interactions. By accessing time-dependent atomic correlations in energy materials, we resolve the long-standing disagreement between local and average structure probes and show that spontaneous anisotropy is ubiquitous in cubic IV–VI materials.Peer reviewe
A regime shift in the Southeast Greenland marine ecosystem
Get PDFFunding: This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 869383(ECOTIP), from the EU's Horizon 2020 Marie Sklodowska-Curie grant agreement No. 101025534 (WARMM), and from the Nordic Council of Ministers AG-Fisk Grant number (209)-2020-LEGCO. Observations at the Icelandic FX9 and RE8 stations are part of the hydrographic monitoring program, ástand sjávar, of the Marine and Freshwater Research Institute, Iceland. Fylla Bank station is monitored by the Greenland Institute of Natural Resources.Two major oceanographic changes have recently propagated through several trophic levels in coastal areas of Southeast Greenland (SEG). Firstly, the amount of drift-ice exported from the Fram Strait and transported with the East Greenland Current (EGC) has decreased significantly over the past two decades, and a main tipping element (summer sea ice) has virtually disappeared since 2003 leading to a regime shift in oceanographic and ecological conditions in the region. The following 20-year period with low or no coastal sea ice is unique in the 200-year history of ice observations in the region, and the regime shift is also obvious in the volume of ice export through the Fram Strait after 2013. In the same period, the temperature of the EGC south of 73.5 N has increased significantly (>2°C) since 1980. Secondly, the warm Irminger Current, which advects warm, saline Atlantic Water into the region, has become warmer since 1990. The lack of pack ice in summer together with a warming ocean generated cascading effects on the ecosystem in SEG that are manifested in a changed fish fauna with an influx of boreal species in the south and the subarctic capelin further north. At higher trophic levels there has been an increase in the abundance of several boreal cetaceans (humpback, fin, killer, and pilot whales and dolphins) that are either new to this area or occur in historically large numbers. It is estimated that the new cetacean species in SEG are responsible for an annual predation level of 700,000 tons of fish. In addition, predation on krill species is estimated at >1,500,000 tons mainly consumed by fin whales. Simultaneously, there has been a reduction in the abundance and catches of narwhals and walruses in SEG and it is suggested that these species have been impacted by the habitat changes.Peer reviewe
Structural polytypism in B-site deficient azetidinium-based pnictogen halide hexagonal perovskites
Get PDFFunding: H.L. would like to thank the University of St. Andrews for financial support via a St. Leonard’s scholarship. The authors acknowledge facilities access made possible through support from the EPSRC Light Element Analysis Facility Grant EP/T019298/1 and the EPSRC Strategic Equipment Resource Grant EP/R023751/1.Azetidinium (Az+)-based antimony and bismuth organic–inorganic hybrid halide B-site-deficient perovskite analogues Az3B2X9 (B3+ = Sb, Bi; X– = Cl, Br, I) were systematically studied. All Az3B2X9 stoichiometries adopt hexagonal close-packed perovskite structures with the 6H (hcc)2 stacking sequence, differing only in the positions of the ordered B-site vacancies. In Az3Sb2Cl9 and Az3Sb2Br9 ordering of B-site vacancies in a single face-sharing octahedral layer leads to the formation of an unusual 2D layered polar structure with the P63mc space group. Variable-temperature single-crystal and powder XRD, DSC, DTA, and dielectric spectroscopy showed several successive phase transitions at low temperatures associated with distortions of the octahedral framework and order/disorder of the Az+ cation. In contrast, in Az3Sb2I9, Az3Bi2Br9, and Az3Bi2I9, the preferred arrangement of vacancies at corner-sharing octahedral sites generates a 0D “dimer” structure. This work highlights the flexibility for structural variations based on particular configurations of vacancy ordering in B-site-deficient halide perovskites.Peer reviewe
Accounting for non-random samples with distance sampling to estimate population density
Get PDFFunding was provided by the Pennsylvania Game Commission (Research Project 23, 30, 31 and 47). We thank the many field technicians who collected data. T.A.M. thanks partial support by CEAUL (funded by FCT—Fundação para a Ciência e a Tecnologia, Portugal DOI: 10.54499/UIDB/00006/2020).1. A critical assumption of standard distance sampling is that sampling lines are located such that animals are uniformly distributed as a function of distance from the line. Failure to meet this assumption can introduce bias in the estimator. 2. Many studies have used landscape features, such as roads or rivers, as lines, which can violate assumptions of distance sampling in two ways. First, animals may be attracted or repelled by the landscape feature due to human activity (e.g. along roads) or habitat characteristics associated with the feature (e.g. rivers). Second, sampling along landscape features may not be representative of the larger area of interest. 3. We used auxiliary data to generalize the distance sampling estimator and relax assumptions of a uniform distribution of animals relative to distance from the line (i.e. density gradient) and to allow the distribution of animals to differ by habitat type. The generalized estimator provides unbiased estimates of density within the area sampled but may not be representative of the study area. 4. To address the problem of landscape features providing unrepresentative sampling, we used a resource selection model to estimate the proportion of the population that occurred within the surveyed area to obtain an estimate of abundance for the desired area of inference. 5. We demonstrate our modified distance sampling estimator using white-tailed deer (Odocoileus virginianus) in a 972-km2 study area. We conducted infrared surveys of deer from roads to collect distance-to-transect data. We used locations of radio-collared deer to model the distribution of deer relative to the transects and to develop a resource selection model of deer based on distance to roads, habitat type, elevation and slope to account for roads being a non-representative sample of the study area. 6. Synthesis and applications. When using landscape features as survey lines, the density gradient and deer distribution can introduce either positive or negative bias, which makes it impossible to assess the bias introduced without auxiliary data. The estimator we developed can improve precision because we obtained a better fit to distance observations and accounts for non-random placement of transects with minimal loss of precision.Peer reviewe
A cultural explanation of Roman Asinus : function and fiction
Get PDFThis study investigates the various roles of the asinus (the donkey/ass), specifically the domestic asinus (Equus africanus asinus) in the Roman world, exploring its dual functions as a practical animal and cultural symbol. The core question guiding this research is: How does the domestic asinus operate in the Roman Empire, both as a utilitarian entity and symbolic representation, and how did its significance transition from purely functional uses to carrying deeper cultural meanings?
To address this inquiry and draw a complete view of the asinus in the Roman world, the study employs an interdisciplinary approach combining biological, economic, literary, and religious viewpoints based on a materialist view of history. The analysis is organized into three main sections, each addressing distinct yet overlapping dimensions of the asinus’ societal impact. The first section focuses on the biological characteristics of the asinus, discussing how its physical traits shape practical applications. The second section investigates literary portrayals of the asinus, particularly its associations with servitude, foolishness, and desire, while analyzing how these depictions mirrored the animal’s real-world roles. The third evaluates the symbolic value of the asinus in Roman religious practices, tracking shifts in cultural interpretations during the collision between traditional pagan beliefs and emerging Christian thought. By synthesizing these interconnected perspectives, the study illustrates how the asinus evolved beyond its basic role as a work animal to become a meaningful cultural marker
When sardines disappear : tracking common dolphin, Delphinus delphis, distribution responses along the western Iberian coast
Get PDFFunding: This study was supported by the ERASMUS+ programme from the European Commission through a scholarship granted to the lead author as a student of the Erasmus Mundus Joint Master Degree in Water and Coastal Management (WACOMA) 2020/2022 (WACOMA; ProjectNo.586596-EPP-1-2017-1-IT-EPPKA1-JMD MOB). This study received Portuguese national funds from FCT—Foundation for Science and Technology through projects UIDB/04326/2020 (DOI:10.54499/UIDB/04326/2020), UIDP/04326/2020 (DOI:10.54499/UIDP/04326/2020), and LA/P/0101/2020 (DOI:10.54499/LA/P/0101/2020) to CCMAR. TAM thanks partial support by CEAUL (funded by FCT—Fundação para a Ciência e a Tecnologia, Portugal DOI: 10.54499/UIDB/00006/2020). Most of the data collection was performed in the aim of several projects co-funded through the LIFE Programme (a funding instrument for the environment and climate action from the European Commission), the Interreg Atlantic Area (by European Commission), the European Maritime and Fisheries Fund (EMFF) in Portugal (Mar2020), the Fundo Biodiversidade and the Fundo Ambiental (both from the Portuguese government), namely LIFE IBAS Marinhas (LIFE 04NAT/PT/000213), FAME (2009-1/089), LIFE MarPro (LIFE09 NAT/PT/000038), LIFE Berlengas (LIFE13 NAT/PT/000458), MedAves Pesca (MAR-01.04.02-FEAMP-0023), and LIFE Ilhas Barreira (LIFE18/NAT/PT/000927).The common dolphin, Delphinus delphis, is the most abundant cetacean species along the western Iberian Peninsula and faces many anthropogenic threats, with bycatch being the most impactful. Its preferred prey, sardine (Sardina pilchardus), has shown fluctuating abundance over the past decade, potentially influencing dolphin distribution. This study provides the first insights into common dolphin distribution along the western Iberian coast, using sighting data from vessel research surveys (2005–2020) to identify hotspot areas while accounting for monthly and seasonal distributions overlapping with sardine abundance. Common dolphin hotspots were located along the central–western and southern Portuguese mainland coasts, coinciding with important fishing ports, oceanographic features, and sardine juvenile habitats. Furthermore, during 2013–2016, common dolphins were observed significantly farther from the coast, coinciding with a period of particularly low coastal sardine biomass. However, GAM analysis indicated that the relationship between sardine biomass and the distance of common dolphins was not significant. This study highlights the major common dolphin hotspots and presents the most comprehensive temporal and distribution maps of the common dolphin along the western Iberian coast, particularly in response to sardine availability. These results can be used by managers to inform conservation measures and for the sustainable management of the Portuguese sardine purse seine fishery fleet, which interacts the most with the species.Peer reviewe
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