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Cognitive and sensory abilities are vital in affecting survival under predation risk, leading to selection on brain anatomy. However, how exactly predation and brain evolution are linked has not yet been resolved, as current empirical evidence is inconclusive. This may be due to predation pressure having different effects across life stages and/or due to confounding factors in ecological comparisons of predation pressure. Here, we used adult guppies (Poecilia reticulata) to experimentally test how direct predation during adulthood would impact the relative brain size and brain anatomy of surviving individuals to examine if predators selectively remove individuals with specific brain morphology. To this end, we compared fish surviving predation to control fish, which were exposed to visual and olfactory predator cues but could not be predated on. We found that predation impacted the relative size of female brains. However, this effect was dependent on body size, as larger female survivors showed relatively larger brains, while smaller survivors showed relatively smaller brains when compared to control females. We found no differences in male relative brain size between survivors and controls, nor for any specific relative brain region sizes for either sex. Our results corroborate the important, yet complex, role of predation as an important driver of variation in brain size.

This work aimed to produce porous poly-hydroxybutyrate (PHB) pellets in order to evaluate the pellets as a support for immobilization of the metagenomic lipase, LipG9. Four types of pelletized PHB particles with different morphological characteristics were obtained using the double emulsion and solvent evaporation technique (DESE). The micropores of these PHB pellets had similar average diameters (about 3 nm), but the pellets had different specific surface areas: 11.7 m

Biochar amendments add persistent organic carbon to soil and can stabilize rhizodeposits and existing soil organic carbon (SOC), but effects of biochar on subsoil carbon stocks have been overlooked. We quantified changes in soil inorganic carbon (SIC) and SOC to 2 m depth 10 years after biochar application to calcareous soil. The total soil carbon (i.e., existing SOC, SIC, and biochar-C) increased by 71, 182, and 210% for B30, B60, and B90, respectively. Biochar application at 30, 60, and 90 t ha–1 rates significantly increased SIC by 10, 38, and 68 t ha–1, respectively, with accumulation mainly occurring in the subsoil (below 1 m). This huge increase of SIC (mainly CaCO3) is ∼100 times larger than the inorganic carbon present in the added biochar (0.3, 0.6, or 0.9 t ha–1). The benzene polycarboxylic acid method showed that the biochar-amended soil contained more black carbon particles (6.8 times higher than control soil) in the depth of 1.4–1.6 m, which provided the direct quantitative evidence for biochar migration into subsoil after a decade. Spectral and energy spectrum analysis also showed an obvious biochar structure in the biochar-amended subsoil, accompanied by a Ca/Mg carbonate cluster, which provided further evidence for downward migration of biochar after a decade. To explain SIC accumulation in subsoil with biochar amendment, the interacting mechanisms are proposed: (1) biochar amendment significantly increases subsoil pH (0.3–0.5 units) 10 years after biochar application, thus forming a favorable pH environment in the subsoil to precipitate HCO3–; and (2) the transported biochar in subsoil can act as nuclei to precipitate SIC. Biochar amendment enhanced SIC by up to 80%; thus, the effects on carbon stocks in subsoil must be understood to inform strategies for carbon dioxide removal through biochar application. Our study provided critical knowledge on the impact of biochar application to topsoil on carbon stocks in subsoil in the long term.

Materials capable of oxidizing in a protective manner at ultrahigh (>1700 °C) temperatures are needed to push beyond this barrier defined by SiC. Although possessing attractive mechanical properties and oxidation resistance, SiC-based materials are ultimately temperature limited by the melting point of SiO2. The vast array of ultra-high and high temperature ceramic literature indicates the majority of these materials, like borides, carbides, MAX-phases, and high-entropy ceramics, fall woefully short regarding oxidation resistance. However, for specific applications, like low-orbit aeropropulsion, high ballistics coefficient atmospheric re-entry, and hypersonic cruise, there are a few promising materials. In the present review, oxidation criteria are gathered to build application specific heuristics and are then applied to a multitude of ultra-high temperature ceramics to gauge material efficacy. Discussion of oxidation kinetics, mechanisms and reaction products is offered for each material, identifying strengths, weaknesses, and the remaining gaps in our knowledge.

Background Medical and surgical fields continue to be marred by gender disparities. The “leaky pipeline” effect, representing a gradual decline in female representation along the academic ladder, has been well documented in plastic surgery. However, gender differences in abstract presentation at national plastic surgery meetings and subsequent publications remains elusive. Methods We reviewed abstracts presented at the 2014 and 2015 annual meetings of the American Association of Plastic Surgeons (AAPS); American Society of Plastic Surgeons (ASPS), and the Plastic Surgery Research Council (PSRC). Several abstract characteristics including the names of the first and last authors were extracted. Genderize.io and Google search were used to identify the authors’ gender. Results We identified 1174 abstracts presented at the three identified meetings. Females comprised 29% of the presenters and 16% of abstract senior authors (ASAs). No gender differences were identified between the meetings, type of presentation (oral versus poster), and year of presentation. The only difference was in the subspecialty of the abstracts. Successful conversion to full-text articles was similar for male and female presenters (68% versus 62%, P = 0.065) but higher for male ASAs (68% versus 59%, P = 0.01). When an author change occurred, female presenters and ASAs were more likely to be replaced by males (P Conclusion Gender differences continue to be evident in academic plastic surgery with women constituting a minority of both presenters and senior authors on abstracts presented at national plastic surgery meetings. Future work should assess whether flexible and supportive work policies can foster greater female representation in academic plastic surgery.

Machine learning is a rapidly growing subset of artificial intelligence (AI) which involves computer algorithms that automatically build mathematical models based on sample data. Systems can be taught to learn from patterns in existing data in order to make similar conclusions from new data. The use of AI in facial emotion recognition (FER) has become an area of increasing interest for providers who wish to quantify facial emotion before and after interventions such as facial reanimation surgery. While FER deep learning algorithms are less subjective when compared to layperson assessments, the databases used to train them can greatly alter their outputs. There are currently many well-established modalities for assessing facial paralysis, but there is also increasing interest in a more objective and universal measurement system to allow for consistent assessments between practitioners. The purpose of this article is to review the development of AI, examine its existing uses in facial paralysis assessment, and discuss the future directions of its implications.

Since the end of the Cold War, the UN has extended many of its missions in conflict zones to include political, military, and humanitarian activities. Many humanitarian nongovernmental organizations have been critical of these “integrated” UN missions, claiming that they can blur the distinction between political, military, and humanitarian action, thus placing humanitarian aid workers at risk of retaliation from warring factions opposed to the UN’s political objectives. This proposition is empirically tested using generalized methods of moments statistical analysis of sixty-seven countries that experienced intrastate conflict between 1997 and 2018. When assessing attacks in general—to include the sum of aid workers killed, wounded, and kidnapped—the results indicate that humanitarian aid workers are more likely to come under attack in countries that have an integrated UN mission. However, when the attacks are assessed separately, results show that this relationship holds only with aid workers who are killed in the field.

International audience; Discrete aurorae have been observed at Mars by multiple spacecraft, including Mars Express, Mars Atmosphere and Volatile EvolutioN (MAVEN), and most recently the United Arab Emirates Hope spacecraft. Meanwhile, there have been studies on the source particles responsible for producing these detectable aurorae (termed "auroral electrons"). By utilizing empirical criteria to select auroral electrons established by Xu et al. (2022, https://doi.org/10.1029/2022GL097757), we conduct statistical analyses of the impact of upstream drivers on the occurrence rate and fluxes of auroral electrons. We find the occurrence rate increases with upstream dynamic pressure and weakly depends on the interplanetary magnetic field strength. Meanwhile, the integrated auroral electron flux somewhat decreases with increasing upstream drivers. Auroral electron precipitation also occurs more frequently and is more intense over regions of strong crustal fields compared to weak crustal fields. Aside from emissions, auroral electrons are expected to cause significant impact ionization and enhance the plasma density locally. In this study, we also quantify the nightside ionospheric impact of auroral electron precipitation, specifically the thermal ion (O+, O2+, and CO2+) density enhancement, with MAVEN observations. Our results show that the ion density is increased by up to an order of magnitude at low altitudes. The crustal effects on ion density profiles for nominal electron and auroral electron precipitation are also discussed.

Preston Greene (2020) argues that we should not conduct simulation investigations because of the risk that wemight be terminated if our world is a simulation designed to research various counterfactuals about the world of the simulators. In response, we propose a sequence of arguments, most of which have the form of an "even if? response to anyone unmoved by our previous arguments. It runs thus: (i) if simulation is possible, then simulators are as likely to care about simulating simulations as they are likely to care about simulating basement (i.e. nonsimulated) worlds. But (ii) even if simulations are interested only in simulating basement worlds the discovery that we are in a simulation will have little or no impact on the evolution of ordinary events. But (iii) even if discovering that we are in a simulation impacts the evolution of ordinary events, the effects of seeming to do so could also happen in a basement world, and might be the subject of interesting counterfactuals in the basement world. Finally, (iv) there is little reason to think that there is a catastrophic effect from successful simulation probes, and no argument from the precautionary principle can be used to leverage the negligible credence one ought have in this. Thus, if we do develop a simulation probe, then let?s do it.

Abstract In recent years, many studies have investigated the potential state dependence of individual differences in behaviour, with the aim to understand the proximate and ultimate causes and consequences of animal personality. Among the potential state variables that could affect behavioural expression is size and mass, but few studies have found associations at the among-individual levels. Insufficient sampling and incorrect analysis of data are cited as impediments to detecting correlations, if they exist. Here, we conducted a study using 100 pillbugs (Armadillidium vulgare) and assayed their defensive behaviour 24 times each over time and across familiarity contexts, to test the asset protection hypothesis that predicts a negative correlation between boldness and mass, and with increases in mass over time. Multivariate mixed models revealed that despite mostly consistent individual behavioural differences over time (modest slope variance) and across contexts (near-parallel reaction norms), and 18-fold range in starting mass, there was no correlation between individual mean mass and boldness. However, individuals that gained more mass over time may have been more ‘shy’ compared to those gaining less mass, but the correlation was weak and observed variation in mass gain was small. There was also a mean level trend of increasing shyness over time that was coincident with mean level mass increases over time. Together, our study provides weak evidence for the asset protection hypothesis, whereby individuals that accumulate more resources are thought to protect them through risk averse behaviour. Significance statement Individual variation in ‘state’, such as mass or energy reserves, is thought to be a predictor of individual differences in behaviour that are consistent over time. However, few studies reveal such links, and several studies suggest insufficient sampling may explain null results in most studies. We studied 100 animals sampled 24 times each in a controlled setting to reveal stable individual differences in mean behaviour over time and across contexts; however, individual behaviour was unrelated to large differences in individual mass but weakly related to increases in mass through time whereby individuals became more shy and those growing faster were somewhat more shy. Our results provide little evidence for the asset protection hypothesis.

Behavioral and physiological ecologists have long been interested in explaining the causes and consequences of trait variation, with a focus on individual differences in mean values. However, the majority of phenotypic variation typically occurs within individuals, rather than among individuals (as indicated by average repeatability being less than 0.5). Recent studies have further shown that individuals can also differ in the magnitude of variation that is unexplained by individual variation or environmental factors (i.e., residual variation). The significance of residual variation, or why individuals differ, is largely unexplained, but is important from evolutionary, methodological, and statistical perspectives. Here, we broadly reviewed literature on individual variation in behavior and physiology, and located 39 datasets with sufficient repeated measures to evaluate individual differences in residual variance. We then analyzed these datasets using methods that permit direct comparisons of parameters across studies. This revealed substantial and widespread individual differences in residual variance. The magnitude of individual variation appeared larger in behavioral traits than in physiological traits, and heterogeneity was greater in more controlled situations. We discuss potential ecological and evolutionary implications of individual differences in residual variance and suggest productive future research directions., Animals are typically quite unpredictable in behavior with the majority of variance unexplained. We returned to raw data of previously published work, and found almost ubiquitously that individuals vary in their predictability. We discuss potential ecological and evolutionary implications of individual differences in residual variance and suggest productive future research directions.

Humanitarian mission trips have been organized by several residency programs and organizations to cater to surgical care in underdeveloped countries. While there is cross-talk on the existence of such opportunities, there is a paucity of guidance to residents on participation in such trips, their benefits, and the myriad of intangibles to consider while planning to pursue such opportunities. Through this article, the authors highlight the background and utility of humanitarian surgical missions and summarize the clinical and surgical experiences that these trips offer for residents choosing to embark on these altruistic journeys.