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BACKGROUND: Cardiac troponin concentrations are lower in women than men. We examined whether age- and risk factor-related changes in cardiac troponin over the life course differ by sex and if the trajectory of cardiac troponin was informative in respect of cardiovascular outcomes in women and men in the general population. METHODS: In the Whitehall II cohort, high-sensitivity cardiac troponin I concentrations were measured on 3 occasions over a 15-year period. Using linear mixed-effects models, the sex-specific trajectories of cardiac troponin were evaluated, and the relationship with conventional cardiovascular risk factors determined. Using multistate joint models, the association between sex-specific trajectories of cardiac troponin and a composite outcome of nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death was evaluated. RESULTS: In 2142 women and 5151 men (mean, 58±7 and 57±7 years of age, respectively), there were 177 (8.3%) and 520 (10.1%) outcome events, respectively, during a median follow-up of 20.9 (25th to 75th percentile, 15.8–21.3) years. Cardiac troponin concentrations were persistently lower in women than in men (median baseline concentration: 2.4 [25th to 75th percentile, 1.7–3.6] ng/L versus 3.7 [25th to 75th percentile, 2.6–5.8] ng/L, respectively, P P interaction P interaction =0.008) and diabetes ( P interaction =0.003). During follow-up, cardiac troponin concentrations were associated to the outcome in both women and men (adjusted hazard ratio per 2-fold difference [95% CI, 1.34 (1.17–1.52) and 1.30 (1.21–1.40), respectively], P interaction = 0.752). The slope of cardiac troponin was significantly associated with the outcome in women, but not in men (adjusted hazard ratio [95% CI, 2.70 (1.01–7.33) and 1.31 (0.62–2.75), respectively], P interaction = 0.250). CONCLUSIONS: Trajectories of cardiac troponin differ between women and men in the general population, with differing associations to conventional risk factors and cardiovascular outcomes. Our findings highlight the importance of a sex-specific approach when serial cardiac troponin testing is applied for cardiovascular risk prediction.

In the modern period, the cities of Syria are faced with unprecedented destruction of historical buildings due to military operations in the country. In this regard, the historical cities of Syria need to study the current state of the urban environment in order to determine the promising directions and principles for its restoration, considering regional characteristics. The article discusses the specifics of the planning structure of the historical cities of Syria and their modern urban planning problems on the example of the city of Damascus. The authors of the study carried out a retrospective analysis and identified the main stages of the historical development of the central part of the city of Damascus (Roman, Islamic, French and modern), conducted a comparative analysis of the development stages of the historical Syrian cities of Aleppo and Latakia. The planning structure of the historical city center, its current location in the city structure, the state of cultural heritage sites, as well as transport and pedestrian accessibility are analyzed. The analysis revealed a number of urban planning problems, including: the spread of destruction in the structure of the city, the destruction of cultural heritage sites, the formed illegal residential development, the insufficient number of green areas in the central part of the city, problems associated with transport infrastructure, etc., promising directions for their solutions

Top predators play key roles within their respective ecosystems. However, their ability to adjust their behaviors in response to changes in environmental conditions and food web structure, which is important in light of climate change and continued anthropogenic disturbance, is still unclear in many ecosystems. We combined stomach content and stable isotope analyses to study the trophic ecology and plasticity of the dominant top predators—the bull shark Carcharhinus leucas and the alligator gar Atractosteus spatula—in 2 estuaries of the northwestern Gulf of Mexico. Both species showed a high degree of prey preference and predominantly fed on mugilids. Juvenile bull sharks were also demersal foragers with a high relative trophic position (TP ≈ 4), feeding heavily on sea catfishes (Bagre marinus and Ariopsis felis) and red drum Sciaenops ocellatus. Comparatively, alligator gars were ambush foragers with TP ≈ 3 that targeted schools of gulf menhaden Brevoortia patronus. Sharks and gars exhibited overlap in their trophic interactions, indicating potential competition for prey, but our results highlight mechanisms that mitigate competition, including spatial partitioning and intraspecific variability. The diets of both species also appeared highly flexible, with individuals able to adjust to spatiotemporal shifts in prey availability. These findings suggest the bull shark and the alligator gar may be somewhat resilient to the ecological change associated with climate change and anthropogenic disturbances and highlight the utility of combining different approaches to refine our understanding of the ecological roles of top predators.

International audience; The management of migratory taxa relies on the knowledge of their movements. Among them, ontogenetic habitat shift, from nurseries to adult habitats, is a behavioural trait shared across marine taxa allowing resource partitioning between life stages and reducing predation risk. As this movement is consistent over time, characterizing its timing is critical to implement efficient management plans, notably in coastal areas to mitigate the impact of fisheries on juvenile stocks.In the Mexican Pacific, habitat use of the smooth hammerhead shark (Sphyrna zygaena) is poorly described, while the species is heavily harvested. Given the large uncertainties associated with the timing of out-migration from coastal nursery grounds to offshore waters prior to reproductive maturity, a more precise assessment of smooth hammerhead shark movements is needed.Photochemical degradation of mercury imparts mass-independent isotope fractionation (?Hg-199) which can be used to discriminate between neonate coastal shallow habitats and the offshore deep foraging patterns of late juveniles. Here, we present the application of muscle ?Hg-199 as molecular clocks to predict the timing of ontogenetic habitat shifts by smooth hammerhead sharks, based on their isotopic compositions at the initial and arrival habitats and on muscle isotopic turnover rate.We observed decreases in ?Hg-199 values with shark body length, reflecting increasing reliance on offshore mesopelagic prey with age. Coastal residency estimates indicated that smooth hammerhead sharks utilize coastal resources for 2 years prior to offshore migration, suggesting a prolonged residency in these ecosystems.Policy implications. This study demonstrates how mercury stable isotopes and isotopic clocks can be implemented as a complementary tool for stock management by predicting the timing of animal migration-a key aspect in the conservation of marine taxa. In the Mexican Pacific, fishing pressure on shark species occurs in coastal habitats depleting juvenile stocks. Consequently, management decision support tools are imperative for effectively maintaining early life stage population levels over time. The finding that smooth hammerhead sharks extensively rely on highly fished habitats for 2 years after parturition supports the relevance of establishing a size limit in coastal fisheries and demonstrates how the current temporal shark fishing closure could lack efficiency for the species.

People with HIV (PWH) and community members have advocated for the development of a home-based viral load test device that could make analytical treatment interruptions (ATIs) less burdensome.We assessed community acceptability of a novel home-based viral load test device.In 2021, we conducted 15 interviews and 3 virtual focus groups with PWH involved in HIV cure research. We used conventional thematic analysis to analyze the data.PWH viewed the home-based viral load test device as a critical adjunct in ongoing HIV cure trials with ATIs. The ability to test for viral load at home on demand would alleviate anxiety around being off ART. Participants drew parallels with glucometers used for diabetes. A preference was expressed for the home-based test to clearly indicate whether one was detectable or undetectable for HIV to mitigate risk of HIV transmission to partners. Perceived advantages of the device included convenience, sense of control, and no puncturing of veins. Perceived concerns were possible physical marks, user errors and navigating the logistics of mailing samples to a laboratory and receiving test results. Participants expressed mixed effects on stigma, such as helping normalize HIV, but increased potential for inadvertent disclosure of HIV status or ATI participation. Increasing pluri-potency of the device beyond viral load testing (e.g., CD4+ count test) would increase its utility. Participants suggested pairing the device with telemedicine and mobile health technologies.If proven effective, the home-based viral load test device will become a critical adjunct in HIV cure research and HIV care.

PURPOSE Metastasis-free survival (MFS), but not event-free survival, is a validated surrogate end point for overall survival (OS) in men treated for localized prostate cancer. It remains unknown if this holds true in biochemically recurrent disease after radical prostatectomy. Leveraging NRG/RTOG 9601, we aimed to determine the performance of intermediate clinical end points (ICEs) as surrogate end points for OS in recurrent prostate cancer. MATERIALS AND METHODS NRG/RTOG 9601 randomly assigned 760 men with recurrence after prostatectomy to salvage radiation therapy with 2 years of placebo versus bicalutamide 150 mg daily. ICEs assessed were biochemical failure (BF) per NRG/RTOG 9601 (prostate-specific antigen nadir + 0.3-0.5 ng/mL or initiation of salvage hormone therapy; [BF1]) and NRG/RTOG 0534 (prostate-specific antigen nadir+2 ng/mL; [BF2]), distant metastasis (DM), and MFS (DM or death). Surrogacy was assessed by the Prentice criteria and a two-stage meta-analytic approach (condition one assessed at the patient level with Kendall's τ and condition two assessed by randomly dividing the entire trial cohort into 10 pseudo trial centers and calculating the average R2 between treatment hazard ratios for ICE and OS). RESULTS BF1, BF2, DM, and MFS satisfied the four Prentice criteria. However, with the two-condition meta-analytic approach, there was strong correlation between MFS and OS (τ = 0.86), moderate correlation between DM and OS (τ = 0.66), and weaker correlation between BF1 (τ = 0.25) or BF2 (τ = 0.40) and OS. Similarly, for condition two, the treatment effect of antiandrogen therapy on MFS and OS were correlated ( R2 = 0.67), but this was not true for BF1 ( R2 = 0.09), BF2 ( R2 = 0.12), or DM ( R2 = 0.18) and OS. CONCLUSION MFS is also a strong surrogate for OS in men receiving salvage radiation therapy for recurrence after prostatectomy. Caution should be used when inferring survival benefit from effects on BF in biochemically recurrent prostate cancer. Lack of comorbidity data did not allow us to assess whether BF in men with no/minimal comorbidity could serve as a surrogate for OS.

We provide a generic method of testing path models that include dependent errors, nonlinear functional relationships and using nonnormal, hierarchically structured data. First, we provide a decomposition of the causal model into smaller, independent sets. These sets can be modeled independently of each other with methods that respect the type of data in these sets. Second, we introduce copulas to model the dependent errors between non-normally distributed variables. Our method yields identical results as classical covariance-based path modelling when meeting its assumptions of linearity and normality, outperforms classical SEM given nonlinear functional relationships, and can easily accommodate any parametric probability function and nonlinear functional relationships.

Objectives: Performance anxiety (PA) is debilitating and impacts the sufferer's ability to perform. Forgetfulness, concentration loss, and physical symptoms develop, leading to some giving up performing. Methods: An online questionnaire was used to gather data, including demographic questions and the Kenny Music Performance Anxiety Inventory (K-MPAI). The questionnaire was distributed via social media and the British Association for Performing Arts Medicine (BAPAM) database. Data was collected over a 2-month period and was analyzed using simple proportions with a score of ≥ 104 on the K-MPAI indicating the presence of PA and ≥ 130 indicating notable levels of PA. Results: Thirty-three participants completed the questionnaire (57.6% female). When looking at the ages of participants (18 to 80), the most common age range was 31 to 35 (33%). Two-thirds of participants were deemed to suffer from PA after completing the K-MPAI. A large proportion of participants with PA (63.6%) scored above the threshold score of 130 indicating "significant performance anxiety." Females or currently unemployed performers showed higher levels of PA than other subgroups. However, a chi-squared test showed no significance between sexes (p = 0.32) or employment status (p = 0.31) and the incidence of PA. Conclusion: The research showed that PA is a significant issue in musical theater, as it is with other musicians who have been studied extensively. We conclude that more research is needed to look at appropriate treatments specifically for musical theater performers.

Introduction:Placing an endotracheal tube is a life-saving measure. Direct laryngoscopy (DL) is traditionally the default method. Video laryngoscopy (VL) has been shown to improve efficiency, but there is insufficient evidence comparing VL versus DL in the prehospital settings. This study, comprising a systematic review and random-effects meta-analysis, assesses current literature for the efficacy of VL in prehospital settings.Methods:PubMed and Scopus databases were searched from their beginnings through March 1, 2022 for eligible studies. Outcomes were the first successful intubation, overall success rate, and number of total DL versus VL attempts in real-life clinical situations. Cochrane’s Risk of Bias (RoB) tool and the Newcastle-Ottawa Scale (NOS) were applied to assess risk of bias and study quality; Q-statistics and I2 values were used to assess heterogeneity.Results:The search yielded seven studies involving 23,953 patients, 6,674 (28%) of whom underwent intubation via VL. Compared to DL, VL was associated with a statistically higher risk ratio for first-pass success (Risk Ratio [RR] = 1.116; 95% CI, 1.005-1.239; P = .041; I2 = 87%). The I2 value for the subgroup of prospective studies was 0% compared to 89% for retrospective studies. In addition, VL was associated with higher likelihood of overall success rate (RR = 1.097; 95% CI, 1.01-1.18; P = .021; I2 = 85%) and lower mean number of attempts (Mean Difference = -0.529; 95% CI, -0.922 to -0.137; P = .008).Conclusion:The meta-analysis suggested that VL was associated with higher likelihood of achieving first-pass success, greater overall success rate, and lower number of intubation attempts for adults in the prehospital settings. This study had high heterogeneity, likely presenced by the inclusion of retrospective observational studies. Further studies with more rigorous methodology are needed to confirm these results.

Field geologists are increasingly using unmanned aerial vehicles (UAVs or drones), although their use involves significant cognitive challenges for which geologists are not well trained. On the basis of surveying the user community and documenting experts’ use in the field, we identified five major problems, most of which are aligned with well-documented limits on cognitive performance. First, the images being sent from the UAV portray the landscape from multiple different view directions. Second, even with a constant view direction, the ability to move the UAV or zoom the camera lens results in rapid changes in visual scale. Third, the images from the UAVs are displayed too quickly for users, even experts, to assimilate efficiently. Fourth, it is relatively easy to get lost when flying, particularly if the user is unfamiliar with the area or with UAV use. Fifth, physical limitations on flight time are a source of stress, which renders the operator less effective. Many of the strategies currently employed by field geologists, such as postprocessing and photogrammetry, can reduce these problems. We summarize the cognitive science basis for these issues and provide some new strategies that are designed to overcome these limitations and promote more effective UAV use in the field. The goal is to make UAV-based geological interpretations in the field possible by recognizing and reducing cognitive load.

Objective: Brief computer-delivered interventions (CDIs) reduce college student drinking and related problems but can be less efficacious and enduring than in-person interventions. The present study examined: (a) the utility of emailed personalized boosters after an evidence-based online CDI for alcohol (i.e., eCHECKUP TO GO), and (b) the added value of including protective behavioral strategies (PBS) in boosters containing personalized normative feedback (PNF) versus PNF alone. Method: 528 young adult (ages 18-24) college drinkers (71.6% female; 52.5% Black, 40.3% White) with a mean age of 19.9 years (SD = 1.65) were randomized to receive: CDI-only; CDI plus a PNF-only booster; or CDI plus a booster containing both PNF and PBS feedback. Booster emails were sent 2 weeks post-intervention. Online surveys completed pre-intervention and at 1 and 3 months assessed alcohol consumption, problems, descriptive normative perceptions, and PBS use. Results: The CDI led to significant reductions in alcohol consumption across all conditions, with no effect of boosters on drinking. Controlling for quantity, no reductions in problems were observed. Descriptive norms reduced significantly, with no condition differences. Only PBS use showed condition effects, such that the CDI-only and PNF-only booster groups reported reduced PBS use at 1 month, but the norms-plus-PBS booster group did not. Conclusions: The CDI was sufficient to change alcohol consumption and perceived norms without boosters, although the inclusion of boosters with PBS feedback may mitigate against PBS use reductions. Longer follow-ups may detect delayed booster benefits, or a larger dose through repeated exposure over time may be needed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Memories which are initially dependent upon the hippocampus can gradually be incorporated into cortical networks, a process known as system-level consolidation. Replay, the rapid recapitulation of neural sequences experienced during behaviour, is thought to be a key mechanism supporting consolidation and predominantly occurs during rest and sleep. More generally replay is also held to play a role in memory retrieval, navigation, and likely planning. Consistent with these multiple roles, replay disruption negatively impacts performance on memory related tasks. The hippocampus and associated structures are known to be among the first to exhibit signs of pathology in Alzheimer’s disease; a disorder characterized by progressive memory dysfunction. It is therefore pertinent to understand how functional changes in the hippocampus, including those related to replay, relate to the pathological and symptomatic changes that accumulate of the course of the disease. In this thesis I describe the results of two experiments in which the relationship between hippocampal replay and Alzheimer’s disease are investigated. In the first experiment, I present a characterization of hippocampal replay in the APPNL-G-F knock-in rodent model of Alzheimer’s disease. Place cells were recorded from the CA1 region of the hippocampus as mice performed a radial-arm maze task, and during subsequent sleep. The task was designed to separably identify errors in reference and working memory. APPNL-G-F mice were found to make greater numbers of reference memory errors than control animals. This reduction in memory performance was related to an overall reduction in the rate at which replay occurred, both during sleep and during brief periods of inactivity in the maze. During waking periods, this deficit appeared to result from a reduction in the number of population activity bursts; some of which incorporated bona fide replay sequences. In sleep, this loss was further exacerbated by a reduction in the coherence of replay sequences; fewer of the candidate population bursts carried decodable sequences. It seems plausible that a deeper understanding of how Alzheimer’s pathology produces the deficits in replay described here, may lead to the identification of new therapeutic targets. In the second experiment, I describe the interaction between cholinergic tone in the hippocampus and replay in both wild-type and APPNL-G-F mice. Acetylcholine levels are reduced in Alzheimer’s disease and acetylcholinesterase inhibitors, which increase the availability of acetylcholine in the brain, form one of the few approved therapeutic treatments. However, acetylcholine has been hypothesised to modulate the balance between encoding and consolidation, with falling cholinergic levels being necessary for replay to occur after new memories are encoded. To assess the role of acetylcholine in replay, I used a viral vector to exclusively express Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) in medial septal cholinergic neurons of ChAT-cre mice. DREADDs were activated using systemic injection of an actuator (CNO), stimulating cholinergic release in the hippocampus and other brain regions. CNO was administered immediately prior to sleep, when Alzheimer’s sufferers are typically recommended to take acetylcholinesterase inhibitors. I found that increased cholinergic tone during sleep reduced the rate at which replay sequences occurred in APPNL-G-F mice. However, this changed was not associated with any further reduction in memory performance. Nevertheless, these results do indicate that that timing of therapeutic treatments targeting the cholinergic system should be considered relative to diurnal changes in neuromodulatory levels, and more generally the sleep-wake cycle.

Cyclospora cayetanensis is a foodborne protozoan parasite that causes outbreaks of diarrheal illness (cyclosporiasis) with clear seasonality worldwide. In the environment, C. cayetanensis oocysts are very robust, and contact with contaminated soil may serve as an important vehicle in the transmission of this organism, and it is considered a risk factor for this infection. The present study evaluated a flotation concentration method, previously shown to provide the best detection results when compared with DNA isolation directly from soil samples, in two main types of farm soil, silt loam soil and sandy clay loam, as well as in commercial potting mix samples inoculated with different numbers of C. cayetanensis oocysts. The flotation method was able to detect as few as 10 oocysts in 10 g of either type of farm soil without modifications, but needed an extra wash and samples of reduced size for the processing of the commercial potting mix to be able to detect 20 oocysts/5 g. A recently modified real-time PCR method for the detection of C. cayetanensis based on a mitochondrial gene target was also evaluated using selected samples of each type of soil. This comparative study confirmed that the concentration of oocysts in soil samples by flotation in high-density sucrose solutions is a sensitive method that can detect low numbers of oocysts in different types of soil.

[Abstract] Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean values for six vascular plant traits. Together, these traits –plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass – define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition and thorough quality control produced the largest and, to our knowledge, most accurate compilation of empirically observed vascular plant species mean traits to date. The study has been supported by the TRY initiative on plant traits (https://www.try-db.org). TRY is an initiative of the Max Planck Institute for Biogeochemistry, bioDISCOVERY/Future Earth (ICSU), the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig and Núcleo DiverSus (CONICET- Universidad Nacional de Córdoba, Argentina). The Global Spectrum of Plant Form and Function study has been supported by the European BACI project (Towards a Biosphere Atmosphere change Index, EU grant ID 640176), and grants to SD by FONCyT, CONICET, Universidad Nacional de Córdoba, the Inter-American Institute for Global Change Research, and The Newton Fund (NERC UK – CONICET ARG). VO thanks RSF (#19-14-00038p). Open Access funding enabled and organized by Projekt DEAL

Between 1979 and 1983 soldiers, workers, and students in Ghana launched a revolution to destroy the neo-imperial order. In the Ghanaian historical imagination that era is not remembered for its radical populism but as a time of violent chaos before the nation-state followed the road to purported neoliberal stability. The sudden rise and fall of revolutionary Ghana reveals both the possibility of alternative modes of political power in Africa and how these forms have been contained through both violence and the control of representational practices. In the contemporary moment, it is hard to theorize alternate ideas of freedom and political difference. If we start a study of twentieth-century revolution with a coup d’état in 1979 Accra, Ghana—rather than student upheavals in 1968 Paris, for example—it reorients our understanding of power by showing how young radicals sought an African-grounded sovereignty, an alternate future now forgotten.

Selective Laser Melting is an additive manufacturing practice that permits the production of metal alloy-based parts. While facilitating the design of complex geometry, SLM leads to the fabrication of a unique material structure that showcases distinct behavioural characteristics relative to their traditional methods of material manufacture. Defects that are innate to SLM inspire the presence of a compositional outlook that is inhomogeneous in nature and only serves to hinder part efficiency. Thus, the Theory of Critical Distances offers a refreshed proposal to evaluating notched Ti-6Al-4V material produced by additive manufacturing processes. Key principles of the theory’s working mechanisms are outlined. Subsequently, symmetrical notches of contrasting size are assessed. Findings reveal that the Theory of Critical Distances is adequately compatible with accurate fatigue prediction of SLM Ti-6Al-4V in its as-built state. Additionally, fracture surface analysis reveals that crack initiation is predominantly a surface-based phenomenon. Hereby, increased focus must be given to the quality of processed material that is located at the externalities of additively manufactured components, in order to enhance their service life capabilities. This will induce an increasingly uniform material structure that will allow for more predictable behavioural characteristics.

Metabolic processes of animals are often studied in controlled laboratory settings. However, these laboratory settings often do not reflect the animals’ natural environment. Thus, results of metabolic measurements from laboratory studies must be cautiously applied to free-ranging animals. Recent technological advances in animal tracking allow detailed eco-physiological studies that reveal when, where and how physiological measurements from the field differ from those from the laboratory. We investigated torpor behavior of male common noctule bats (Nyctalus noctula) across different life history stages using two approaches: in controlled laboratory experiments and in the field using calibrated heart rate telemetry. We predicted that non-reproductive males would extensively use torpor to conserve energy, whereas reproductive males would reduce torpor use to promote spermatogenesis. We did not expect differences in torpor use between captive and wild animals as we simulated natural temperature conditions in the laboratory. We found that during the non-reproductive phase, both captive and free-ranging bats used torpor extensively. During reproduction, bats in captivity unexpectedly also used torpor throughout the day, while only free-ranging bats showed the expected reduction in torpor use. Thus, depending on life history stage, torpor behavior in the laboratory was markedly different from the wild. By implementing both approaches and at different life history stages, we were able to better explore the limitations of eco-physiological laboratory studies and make recommendations for when they are an appropriate proxy for natural behavior.

Color polymorphism is an adaptive strategy in which a species exhibits multiple color phenotypes in a population. Often times, phenotypes are variably suited to different environmental conditions which may buffer the population against variable conditions. Modern climate change is creating novel selective pressures for many species, especially in winter habitats. Few studies have quantified the benefits of polymorphism for allowing species to cope with climate-induced environmental change. We investigated how color polymorphism mediates selective pressures in ruffed grouse Bonasa umbellus, a widespread and winter-adapted bird species of North American forests. Ruffed grouse display phenotypic variation in plumage color, ranging from red to gray. Over five winter seasons (2015-2022), we monitored weather conditions, habitat use, and weekly survival for 94 ruffed grouse to test whether individuals had lower survival when grouse were phenotypically mismatched with snow cover (e.g., a gray bird on a snowless landscape or a red bird in snow). Grouse phenotypically mismatched with snow cover had lower survival, but only when winter survival rates were lowest. During winters of lower overall survival, red grouse exhibited higher survival during snow-free periods, whereas gray grouse had higher survival when snow was present. We also found that open habitat negatively impacted survival, regardless of color. While the effect of phenotypic mismatch was variable among years, it was a stronger predictor of winter survival than land cover features, suggesting that snow is an important habitat feature mediating overwinter survival. Our work offers an advancement in understanding how environmental variability affects geographic variation in and maintenance of multiple color phenotypes in seasonally-snow covered environments. Our finding that interactions between color morph and snow cover are important for conferring winter survival provides further evidence that color polymorphism may serve as a buffer against rapidly changing conditions and a pathway for persistence of polymorphic species.

Robust fine tuning of multi-leaf collimator (MLC) Treatment Planning System (TPS) modeling parameters is crucial for creating an optimal beam model, particularly with the ever-increasing accuracy required for advancing techniques. Challenges arise from balancing the trade-off between multiple parameters and therefore the quality of tuning depends on the experience of the physicist and the procedures used. This is in part due to limitations of the MLC modeling within the TPS. As a result, the actual values used have been shown to vary widely between centers. We present and evaluate two different MLC transmission maps to improve the modeling of the Elekta Agility MLC in the RayStation TPS. The model prototypes were developed with discrete and continuous MLC transmission maps assigned to the tongue-and-groove and leaf tip regions. The prototypes aimed to replicate the average doses for synchronous and asynchronous sweeping gap fields, measured using a Farmer chamber in a solid water phantom. This study investigated the impact of these improvements using test fields and a wide variety of measured clinical plans in three different centers. The models achieved good accuracy and the improvements facilitated the standardization of the configuration and commissioning processes and extended the range of validity of TPS dose calculations in wide variety of treatment plans and measuring systems. The simpler MLC prototype with discrete transmission maps performed similarly to the more sophisticated one both in tests and clinical plans and constitutes a good option for routine clinical practice. The need for trade-offs were reduced and the models were successfully configured using a common set of parameters across the three centers, which is useful for reducing the workload and the risks associated with the configuration process, thus improving the accuracy and safety of radiotherapy treatments.

The end of the Pliocene (~2.5-3 Mya) saw a period of biotic turnover in marine ecosystems with significant losses in marine megafauna (36% of genera globally) including the giant apex predator, Otodus megalodon. This recently identified extinction event coincided with a period of notable climatic change, with glaciation of the Northern Hemisphere causing a drop in global sea level. A positive correlation has been found between extinction probability and those genera that had high energy requirements and were associated with coastal, shelf habitats. As such, it has been hypothesised that these extinctions may have been driven by sea level drop resulting in loss of shelf area and a reduction in the neritic zone, a highly productive feeding habitat.Megafauna, and particularly apex predators, are known to play important trophic roles in extant communities yet the ecological consequences of losing these large taxa from marine ecosystems in currently not well understood. Using a trait-based inference model, we reconstructed food webs to assess the impact of this Pliocene extinction event on North Atlantic trophic community structure and dynamics. The model distributes trophic links using rules based on optimal foraging theory and functional traits assigned to every trophic species (e.g., body size, depth distribution and feeding habit). Through analysing the differences in food web topology pre- and post- megafaunal extinction event, we identify consistency in structure and connectedness between taxa within the webs. However, diversity changes within trophic levels and a decrease in competition in the Pleistocene indicates this turnover event did result in changes to the marine ecosystem makeup. Furthermore, our results show that the trophic role held by O. megalodon in the Pliocene appears to have been lost in the Pleistocene, with no other taxa taking its place.In addition to these findings, we also consider alternate hypotheses that may have impacted megafaunal extinction other than shelf loss. As the North Atlantic possesses areas of long continental shelf, neritic zone habitats may have only been shifted, not lost. Consequently, other factors may have played a more significant role.

Convection over the Maritime Continent has large impacts for local extreme weather, as well as for global weather and climate. However, this convection and its impacts are poorly represented in current weather and climate models. This is largely due to complex multi-scale interactions between convection and the ocean, intricate island coastlines and topography, equatorial waves, and larger-scale dynamics such as the Madden-Julian oscillation (MJO). In order to better understand the modulation of convection by the MJO, and its representation in current models, we developed a new modelling suite that couples the Met Office Unified Model to a thermodynamic mixed-layer ocean model with additional corrections to account for ocean dynamics. This allows two-way interactions between the atmosphere and ocean on convection-relevant timescales without the expense of a full dynamical ocean model. We present results from simulations of 10 DJF seasons over the Maritime Continent at grid spacings of 12km (with a mass flux convection scheme) and 2km (without). We investigated the modulation of large-scale convective heating and moistening by MJO phase in both models. We show that: The 2km suite has more variability by MJO phase, and this variability is more realistic than that in the 12km suite when compared to observational data; There is more variability in the type of convection (defined by the shape of heating/moistening profiles) between MJO phases in the 2km suite; The dominant variation is between different types of convection in the two suites. We also present preliminary results on the modulation by the MJO of basic properties of the cloud field like feature size, and feature isotropy.

Halogenated natural products are organic compounds produced by marine bacteria and other marine organisms, as well as created anthropogenically through water chlorination and production as industrial compounds. These compounds can exhibit toxicity, bioaccumulate in the environment, and perform important roles in the regulation of the tropospheric and stratospheric ozone. To date, these compounds are understudied, particularly in Arctic and mid-latitude systems, with limited global data or understanding of spread. This project will share data on both di- and tri- bromoanisoles and bromophenols from the Western Arctic collected on a May-June 2021 cruise in the Beaufort and Chukchi Seas, as well as data collected from the mid-latitude estuary of Long Island Sound during 2022. These data help to close the gap in measurements of HNPs and inform future studies.

Climate change can create challenging conditions for reproduction by creating mismatches between breeding activity, resource availability, and favorable weather. Phenological advancement may mitigate some of these effects, but it can also result in exposing developing offspring to greater temperature variability during reproduction. We combined >300,000 community science breeding records with data on historical temperature to understand how exposure to extreme climatic events (ECEs) has changed for 24 North American songbirds during breeding. More specifically, we wanted to understand if changes in average spring temperature were associated with when the latest cold-snap or earliest heat-wave occurred across the breeding range and the relationship to individual fitness. While average spring temperature increased universally across North America since 1950, the change in timing of ECEs was inconsistent in both direction and magnitude. Moreover, increase in average temperature did not predict the amount of change in average cold-snap and heat-wave timing. Thus, the current relationships between temperature and temperature variability differ from those experienced historically during breeding. After accounting for covariates, we found that 16 of 24 species had reduced reproductive success when a cold-snap occurred during the breeding attempt and 11 of 24 had reduced success when a heat-wave occurred. Four of the five aerial insectivores included showed marked sensitivity to ECEs, as did all the sallying insectivores. For three widespread species, we found evidence for latitudinal differences in susceptibility to temperature extremes. However, the pattern of sensitivity differed for each species, suggesting that life history details might play an important role in species responses to ECEs. Large-scale patterns and consequences of climate change on breeding birds ultimately result from the accumulated effects of individual susceptibility. Our results add to evidence demonstrating that understanding individual and species level sensitivity and linking them to population level processes is critical for predicting vulnerability to changing climates.

The genus Etmopterus is the most speciose group of small bodied deep-sea sharks found throughout the tropical and subtropical Western Atlantic. Despite exhibiting a global distribution at the genus-level, the blurred lantern shark (Etempoterus bigelowi) is known only from a few records in the Western and Southern Atlantic Ocean. Through in-situ video observations using deep-sea landers, we provide two new locality records of the blurred lantern shark from the deep waters off the Cayman Islands, Caribbean Sea. Three unique individuals were recorded across two separate deployments between 653m – 668m. These observations provide the first records of this species in the Caribbean Sea, adding to the minimal knowledge of the species’ distribution throughout the Western Atlantic Ocean.

Understanding the factors shaping patterns of ecological resilience is critical for mitigating the loss of global biodiversity. Throughout aquatic environments, highly mobile predators are thought to serve as important vectors of energy between ecosystems thereby promoting stability and resilience. However, the role these predators play in connecting food webs and promoting energy flow remains poorly understood in most contexts. Using carbon and nitrogen isotopes, we quantified the use of several prey resource pools (small oceanic forage, large oceanics, coral reef, and seagrass) by 17 species of elasmobranch fishes ( n = 351 individuals) in The Bahamas to determine their functional diversity and roles as ecosystem links. We observed remarkable functional diversity across species and identified four major groups responsible for connecting discrete regions of the seascape. Elasmobranchs were responsible for promoting energetic connectivity between neritic, oceanic and deep-sea ecosystems. Our findings illustrate how mobile predators promote ecosystem connectivity, underscoring their functional significance and role in supporting ecological resilience. More broadly, strong predator conservation efforts in developing island nations, such as The Bahamas, are likely to yield ecological benefits that enhance the resilience of marine ecosystems to combat imminent threats such as habitat degradation and climate change.