ABSTRACT
Adaptations of post‐hatching animals have attracted far more study than have embryonic responses to environmental challenges, but recent research suggests that we have underestimated the ...complexity and flexibility of embryos. We advocate a dynamic view of embryos as organisms capable of responding – on both ecological and evolutionary timescales – to their developmental environments. By viewing embryos in this way, rather than assuming an inability of pre‐hatching stages to adapt and respond, we can broaden the ontogenetic breadth of evolutionary and ecological research. Both biotic and abiotic factors affect embryogenesis, and embryos exhibit a broad range of behavioural and physiological responses that enable them to deal with changes in their developmental environments in the course of interactions with their parents, with other embryos, with predators, and with the physical environment. Such plasticity may profoundly affect offspring phenotypes and fitness, and in turn influence the temporal and spatial dynamics of populations and communities. Future research in this field could benefit from an integrated framework that combines multiple approaches (field investigations, manipulative experiments, ecological modelling) to clarify the mechanisms and consequences of embryonic adaptations and plasticity.
Abstract
The escalating drug addiction crisis in the United States underscores the urgent need for innovative therapeutic strategies. This study embarked on an innovative and rigorous strategy to ...unearth potential drug repurposing candidates for opioid and cocaine addiction treatment, bridging the gap between transcriptomic data analysis and drug discovery. We initiated our approach by conducting differential gene expression analysis on addiction-related transcriptomic data to identify key genes. We propose a novel topological differentiation to identify key genes from a protein–protein interaction network derived from DEGs. This method utilizes persistent Laplacians to accurately single out pivotal nodes within the network, conducting this analysis in a multiscale manner to ensure high reliability. Through rigorous literature validation, pathway analysis and data-availability scrutiny, we identified three pivotal molecular targets, mTOR, mGluR5 and NMDAR, for drug repurposing from DrugBank. We crafted machine learning models employing two natural language processing (NLP)-based embeddings and a traditional 2D fingerprint, which demonstrated robust predictive ability in gauging binding affinities of DrugBank compounds to selected targets. Furthermore, we elucidated the interactions of promising drugs with the targets and evaluated their drug-likeness. This study delineates a multi-faceted and comprehensive analytical framework, amalgamating bioinformatics, topological data analysis and machine learning, for drug repurposing in addiction treatment, setting the stage for subsequent experimental validation. The versatility of the methods we developed allows for applications across a range of diseases and transcriptomic datasets.
Feature selection is an important data processing method to reduce dimension of the raw datasets while preserving the information as much as possible. In this paper, an enhanced version of Black ...Widow Optimization Algorithm called SDABWO is proposed to solve the feature selection problem. The Black Widow Optimization Algorithm (BWO) is a new population-based meta-heuristic algorithm inspired by the evolution process of spider population. Three main improvements were included into the BWO to overcome the shortcoming of low accuracy, slow convergence speed and being easy to fall into local optima. Firstly, a novel strategy for selecting spouses by calculating the weight of female spiders and the distance between spiders is proposed. By applying the strategy to the original algorithm, it has faster convergence speed and higher accuracy. The second improvement includes the use of mutation operator of differential evolution at mutation phase of BWO which helps the algorithm escape from the local optima. And then, three key parameters are set to adjust adaptively with the increase of iteration times. To confirm and validate the performance of the improved BWO, other 10 algorithms are used to compared with the SDABWO on 25 benchmark functions. The results show that the proposed algorithm enhances the exploitation ability, improves the convergence speed and is more stable when solving optimization problems. Furthermore, the proposed SDABWO algorithm is employed for feature selection. Twelve standard datasets from UCI repository prove that SDABWO-based method has stronger search ability in the search space of feature selection than the other five popular feature selection methods. These results confirm the capability of the proposed method simultaneously improve the classification accuracy while reducing the dimensions of the original datasets. Therefore, SDABWO-based method was found to be one of the most promising for feature selection problem over other approaches that are currently used in the literature.
Worldwide habitat loss, land-use changes, and climate change threaten biodiversity, and we urgently need models that predict the combined impacts of these threats on organisms. Current models, ...however, overlook microhabitat diversity within landscapes and so do not accurately inform conservation efforts, particularly for ectotherms. Here, we built and field-parameterized a model to examine the effects of habitat loss and climate change on activity and microhabitat selection by a diurnal desert lizard. Our model predicted that lizards in rock-free areas would reduce summer activity levels (e.g. foraging, basking) and that future warming will gradually decrease summer activity in rocky areas, as even large rocks become thermally stressful. Warmer winters will enable more activity but will require bushes and small rocks as shade retreats. Hence, microhabitats that may seem unimportant today will become important under climate change. Modelling frameworks should consider the microhabitat requirements of organisms to improve conservation outcomes.
ABSTRACT
Temperature profoundly affects the rate and trajectory of embryonic development, and thermal extremes can be fatal. In viviparous species, maternal behaviour and physiology can buffer the ...embryo from thermal fluctuations; but in oviparous animals (like most reptiles and all birds), an embryo is likely to encounter unpredictable periods when incubation temperatures are unfavourable. Thus, we might expect natural selection to have favoured traits that enable embryos to maintain development despite those fluctuations. Our review of recent research identifies three main routes that embryos use in this way. Extreme temperatures (i) can be avoided (e.g. by accelerating hatching, by moving within the egg, by cooling the egg by enhanced rates of evaporation, or by hysteresis in rates of heating versus cooling); (ii) can be tolerated (e.g. by entering diapause, by producing heat‐shock proteins, or by changing oxygen use); or (iii) the embryo can adjust its physiology and/or developmental trajectory in ways that reduce the fitness penalties of unfavourable thermal conditions (e.g. by acclimating, by exploiting brief windows of favourable conditions, or by producing the hatchling phenotype best suited to those incubation conditions). Embryos are not simply passive victims of ambient conditions. Like free‐living stages of the life cycle, embryos exhibit behavioural and physiological plasticity that enables them to deal with unpredictable abiotic challenges.
Climate warming can substantially impact embryonic development and juvenile growth in oviparous species. Estimating the overall impacts of climate warming on oviparous reproduction is difficult ...because egg‐laying events happen throughout the reproductive season. Successful egg laying requires the completion of embryonic development as well as hatching timing conducive to offspring survival and energy accumulation. We propose a new metric—egg‐laying opportunity (EO)—to estimate the annual hours during which a clutch of freshly laid eggs yields surviving offspring that store sufficient energy for overwintering. We estimated the EO within the distribution of a model species, Sceloporus undulatus, under recent climate condition and a climate‐warming scenario by combining microclimate data, developmental functions, and biophysical models. We predicted that EO will decline as the climate warms at 74.8% of 11,407 sites. Decreasing hatching success and offspring energy accounted for more lost EO hours (72.6% and 72.9%) than the occurrence of offspring heat stress (59.9%). Nesting deeper (at a depth of 12 cm) may be a more effective behavioral adjustment for retaining EO than using shadier (50% shade) nests because the former fully mitigated the decline of EO under the considered warming scenario at more sites (66.1%) than the latter (28.3%). We advocate for the use of EO in predicting the impacts of climate warming on oviparous animals because it encapsulates the integrative impacts of climate warming on all stages of reproductive life history.
Efectos divergentes del cambio climático sobre la oportunidad de desove de las especies en regiones cálidas y frías
Resumen
El calentamiento global puede tener un impacto considerable sobre el desarrollo embrionario y el crecimiento juvenil de las especies ovíparas. Es complicado estimar el impacto general que tiene el calentamiento global sobre la reproducción ovípara ya que los eventos de desove suceden durante la época reproductiva. El desove exitoso requiere que se complete el desarrollo embrionario y que el momento de eclosión sea favorable para la supervivencia de las crías y la acumulación de energía. Proponemos una nueva medida—oportunidad de desove (OD)—para estimar las horas anuales durante las cuales una puesta de huevos recién desovados produce crías que sobreviven y almacenan suficiente energía para invernar. Estimamos la OD dentro de un modelo de distribución de la especie Sceloporus undulatus bajo las recientes condiciones climáticas y bajo un escenario de calentamiento global mediante la combinación de datos microclimáticos, funciones del desarrollo y modelos biofísicos. Pronosticamos que la OD declinará conforme la temperatura aumente en 74.8% de los 11407 sitios. La disminución del éxito de eclosión y de la energía de las crías explicó más horas perdidas de OD (72.6% y 72.9%) que la presencia de estrés por calor en las crías (59.9%). Una anidación más profunda (a una profundidad de 12 cm) puede ser un ajuste conductual más efectivo para la retención de la OD que los nidos con mayor sombreado (50% de sombra) porque el primero mitigó por completo la declinación de la OD bajo el escenario de calentamiento en más sitios (66.1%) que el segundo ajuste (28.3%). Defendemos el uso de la OD en el pronóstico del impacto del calentamiento global sobre los animales ovíparos porque encapsula los impactos integrales que tiene el calentamiento global sobre todas las etapas de la vida reproductiva. 气候变化在寒冷和温暖地区对物种产卵机会造成不同影响
气候变化在寒冷和温暖地区对物种产卵机会造成不同影响 摘要
气候变暖可能严重影响卵生物种的胚胎发育和幼体生长。由于产卵事件先后发生在整个繁殖季节, 评估气候变暖对卵生物种繁殖的总体影响十分困难。一次成功的产卵除了让胚胎能够完成发育外, 还需要让卵在有利于后代生存和能量积累的时机孵化。我们提出了一个新的指标——产卵机会(EO) ——用来估计一年中一窝新产卵能够产生成功越冬后代的时间。结合微气候数据、胚胎发育数据和生物物理模型, 我们估算了模式物种东部强棱蜥(Sceloporus undulatus)在当前气候条件和气候变暖情景下, 其分布范围内的EO。我们预测, 在东部强棱蜥分布区内的11407个位点中, 74.8%的位点的EO将随着气候变暖而缩短。由孵化成功率降低和后代能量积累减少所造成的EO损失(72.6%和72.9%)大于由新生幼体热压力所造成的EO损失(59.9%)。在气候变暖情景下, 增加产卵巢穴深度(12 cm)可能比在更郁闭的巢穴中产卵(50%郁闭)更有效地减缓EO损失, 因为在东部强棱蜥的例子中前者(66.1%)比后者(28.3%)在更多的地点避免了EO的损失。我们提倡使用EO来预测气候变暖对卵生动物的影响, 因为它概括了气候变暖对繁殖生活史各个阶段的综合影响。
Abstract
We report on the results of a new spectroscopic monitoring campaign of the quasar PG 0026+129 at the Calar Alto Observatory 2.2 m telescope from 2017 July to 2020 February. Significant ...variations in the fluxes of the continuum and broad emission lines, including H
β
and He
ii
, were observed in the first and third years, and clear time lags between them are measured. The broad H
β
line profile consists of two Gaussian components: an intermediate-width H
with an FWHM of 1964 ± 18
and another very broad H
with an FWHM of 7570 ± 83
. H
has long time lags of ∼40–60 days in the rest frame, while H
shows nearly zero time delay with respect to the optical continuum at 5100 Å. The velocity-resolved delays show consistent results: lags of ∼30–50 days at the core of the broad H
β
line and roughly zero lags at the wings. H
has a redshift of ∼400
, which seems to be stable for nearly 30 yr by comparing with archived spectra, and may originate from an infall. The rms spectrum of H
shows a double-peaked profile with brighter blue peak and extended red wing in the first year, which matches the signature of a thin disk. Both the double-peaked profile and the near-zero lag suggest that H
comes from a region associated with the part of the accretion disk that emits the optical continuum. Adopting the FWHM (in the rms spectrum) and the time lag measured for the total H
β
line, and a virial factor of 1.5, we obtain a virial mass of
for the central black hole in this quasar.
Squamate reptiles exhibit two reproductive modes: oviparity and viviparity. Existing large‐scale studies suggest that viviparous species are more vulnerable to climate warming based on viviparous ...species occupying relatively colder environments, which are predicted to decline in availability under climate warming. However, oviparous and viviparous squamates are geographically widespread and their distributions often overlap. Are oviparous or viviparous squamates more vulnerable to climate warming when they inhabit similar thermal environments? We used Sceloporus lizards in North America as a model system to predict the impact of climate warming on oviparous and viviparous species in sympatric zones. We used mechanistic models to quantify the changes in maternal energy balance (MEB) and offspring energy balance (OEB) under a climate warming scenario. We then projected the fitness impacts of future climate warming based on estimates of MEB and OEB. Under a climate warming scenario (RCP8.5), oviparous females are predicted to increase reproductive frequency more than viviparous females, which restricts time for postpartum energy accumulation before the end of the season and decreases MEB. Under climate warming, OEB of oviparous species increased more than viviparous species, but the increases were less geographically widespread. Interestingly, the developmental success and OEB of oviparous species are predicted to decline at some sites under climate warming, which is not predicted to happen for viviparous species. Our results highlight that oviparous species will respond more variably to climate warming than viviparous species. More specifically, oviparous species in hot areas with high temperature variation may be especially vulnerable under climate warming compared to sympatric viviparous species.
Ongoing climate change has profoundly affected global biodiversity, but its impacts on populations across elevations remain understudied. Using mechanistic niche models incorporating species traits, ...we predicted ecophysiological responses (activity times, oxygen consumption and evaporative water loss) for lizard populations at high‐elevation (<3600 m asl) and extra‐high‐elevation (≥3600 m asl) under recent (1970–2000) and future (2081–2100) climates. Compared with their high‐elevation counterparts, lizards from extra‐high‐elevation are predicted to experience a greater increase in activity time and oxygen consumption. By integrating these ecophysiological responses into hybrid species distribution models (HSDMs), we were able to make the following predictions under two warming scenarios (SSP1‐2.6, SSP5‐8.5). By 2081–2100, we predict that lizards at both high‐ and extra‐high‐elevation will shift upslope; lizards at extra‐high‐elevation will gain more and lose less habitat than will their high‐elevation congeners. We therefore advocate the conservation of high‐elevation species in the context of climate change, especially for those populations living close to their lower elevational range limits. In addition, by comparing the results from HSDMs and traditional species distribution models, we highlight the importance of considering intraspecific variation and local adaptation in physiological traits along elevational gradients when forecasting species' future distributions under climate change.
Compared with their high‐elevation (<3600 m asl) counterparts, lizards from extra‐high‐elevation (≥3600 m asl) are predicted to experience a greater increase in activity time and oxygen consumption by 2081–2100, and we predict that lizards at both high‐ and extra‐high‐elevation will shift upslope; lizards at extra‐high‐elevation will gain more and lose less habitat than will their high‐elevation congeners. We therefore advocate the conservation of high‐elevation species in the context of climate change, especially for those populations living close to their lower elevational range limits.
Heat tolerance at the immobile embryonic stage is expected to be critical in determining species vulnerability to climate change. However, how the mean and developmental plasticity of embryonic heat ...tolerance vary geographically, and how these geographic variations affect species' vulnerability under climate change remain unknown. We experimentally determined the mean and developmental plasticity of embryonic acute heat tolerance (EAHT, i.e., heat shock temperature at which embryonic heartbeats ceased) for three latitudinally distributed populations of an oviparous lacertid lizard. The experimental results suggested that the mean EAHT decreased with decreasing latitude and that the reaction norms of EAHT in relation to developmental temperatures showed "flat," "bell-shaped," and "decreasing" patterns at high, medium, and low latitudes, respectively. Based on the means and plasticity of EAHT and weather data across China, we project that the heat stress frequency would increase from the present to the future and increase toward low latitudes. Furthermore, heat stress becomes more extensive with the incorporation of developmental plasticity. Incorporating the mean EAHT during the embryonic development season, heat stress frequency, and climate variables in a species distribution model projects that suitable habitats could move northward in response to ongoing climate change and shrink due to the loss of southern habitat. More-over, even lizards within the areas that are predicted to remain highly suitable are expected to experience increases in heat stress over time, particularly at medium and low latitudes. Our study reveals geographic variation in the mean and developmental plasticity of EAHT and highlights its importance for predicting species vulnerability and range shifts in response to climate change.
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