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ABSTRACT The increase in the frequency and intensity of droughts and heatwaves caused by climate change poses a major threat to biodiversity. In aquatic systems, sedentary species such as freshwater mussels are generally considered more vulnerable to changes in habitat conditions than mobile species such as fish. As mussels provide important ecosystem services, understanding the impacts of drought on freshwater mussels is of particular importance for the management of overall functioning of aquatic ecosystems. We used a comprehensive literature search to provide a systematic overview of direct and indirect effects of drought on freshwater mussels (Bivalvia: Unionida) and an evaluation of mitigation strategies. We found that drought studies were concentrated mostly in the USA, with a focus on the Unionidae family. Topics ranged from the physiological effects of high temperatures, emersion, and hypoxia/anoxia to behavioural and reproductive consequences of drought and the implications for biotic interactions and ecosystem services. Studies spanned all levels of biological organization, from individual responses to population‐ and community‐level impacts and ecosystem‐wide effects. We identified several knowledge gaps, including a paucity of trait‐based evaluation of drought consequences, limited understanding of thermal and desiccation tolerance at the species level, and the synergistic effects of multiple drought stressors on mussels. Although we found many studies provided suggestions concerning management of populations, habitat conditions, and anthropogenic water use, a systematic approach and testing of recommended mitigation strategies is largely lacking, creating challenges for managers aiming to conserve freshwater mussel communities and populations in light of climate change. [ABSTRACT FROM AUTHOR]

Climate heating has the potential to drive changes in ecosystems at multiple levels of biological organization. Temperature directly affects the inherent physiology of plants and animals, resulting in changes in rates of photosynthesis and respiration, and trophic interactions. Predicting temperature‐dependent changes in physiological and trophic processes, however, is challenging because environmental conditions and ecosystem structure vary across biogeographical regions of the globe. To realistically predict the effects of projected climate heating on wildlife populations, mechanistic tools are required to incorporate the inherent physiological effects of temperature changes, as well as the associated effects on food availability within and across comparable ecosystems. Here we applied an agent‐based bioenergetics model to explore the combined effects of projected temperature increases for 2100 (1.4, 2.7, and 4.4°C), and associated changes in prey availability, on three‐spined stickleback (Gasterosteus aculeatus) populations representing latitudes 50, 55, and 60°N. Our results showed a decline in population density after a simulated 1.4°C temperature increase at 50°N. In all other modeled scenarios there was an increase (inflation) in population density and biomass (per unit area) with climate heating, and this inflation increased with increasing latitude. We conclude that agent‐based bioenergetics models are valuable tools in discerning the impacts of climate change on wild fish populations, which play important roles in aquatic food webs. [ABSTRACT FROM AUTHOR]

Temperature is a key driver in determining species distribution and abundance across climatic and geographical gradients. This occurs through direct physiological effects of temperature on performance, but may also result from temperature effects on species interactions.In the current study we experimentally test for temperature‐dependent competition between juvenile anadromous Atlantic salmon and brown trout and evaluate the role of temperature in shaping the relative abundance of these species across 88 Norwegian rivers.When the two species were reared in allopatry their somatic growth rates were similar across a range of temperatures (4–16°C).When reared in sympatry, the growth of salmon was greatly reduced at the coldest temperature relative to when reared in allopatry, whereas this was not the case for trout. The effect of interspecific competition on growth was more similar for the two species at warmer temperatures. Thus, interspecific competition effects were strongly asymmetric only at the lowest temperature, with trout outcompeting salmon.The results from the experiment were reflected in qualitative patterns of relative abundance of salmon and trout in natural populations, which shifted from being trout dominated in rivers with low summer temperatures to being salmon dominated in warmer rivers.These results provide an empirical example of how temperature effects on the relative abundance of species can only be understood in light of information about temperature‐dependent species interactions. [ABSTRACT FROM AUTHOR]

Platycodon grandiflorum, a dual-purpose herb for food and medicine, is widely distributed in Asia. Although P. grandiflorum has relatively low requirements for its growing environment, temperature remains an important ecological factor affecting its growth, development, and quality formation. In order to explore the effect of different temperatures on P. grandiflorum during their growth period, the diversity in growth physiology, platycodin contents, and gene expression of key enzymes were investigated under constant (8 °C, 18 °C, and 28 °C) and variable (8–18 °C, 8–28 °C, and 18–28 °C) temperature conditions at each of the three levels. The results suggested that both constant and variable temperatures at high levels significantly increased the aboveground fresh weight of P. grandiflorum. However, the low–variable temperature was beneficial for the accumulation of dry and fresh weight in the roots. Regardless of whether temperatures were constant or variable at low levels, this increased the content of soluble sugars, proline, and peroxidase in P. grandiflorum, while upregulating the expression levels of key enzyme genes involved in platycodin synthesis. Meanwhile, a low–constant temperature inhibited the photosynthetic rate of P. grandiflorum. Furthermore, medium–constant and large-scale variable temperatures were conducive to the accumulation of platycodins in the roots. This research provides a theoretical basis and data support for the influence of temperature variations on P. grandiflorum quality formation. [ABSTRACT FROM AUTHOR]

Thermal stress causes the overproduction and toxic accumulation of reactive oxygen species (ROS), which seems to be correlated with coral bleaching and, ultimately, death. The reduction of ROS concentration within the coral holobiont could minimize the effects of thermal stress and support efforts to reduce coral decline globally. In the current study, we explored the physiological responses of Pocillopora damicornis to ROS-scavenging bacteria inoculation as well as the microbiome restructuring that correlates with P. damicornis's resilience to thermal stress after probiotic inoculation. Inoculation of corals with ROS-scavenging bacteria enhanced coral health and reduced ROS concentration. Furthermore, the enhanced coral thermal resistance promoted by ROS-scavenging bacteria was also correlated with an overall coral microbiome restructuring. In addition, the complex network relationships between bacteria and Symbiodiniaceae in corals after ROS-scavenging bacteria inoculation contributed to corals' resilience to high temperatures. Besides, coral heat tolerance bacterial biomarkers, such as Myxococcota, were enriched in corals with added ROS-scavenging bacteria. Collectively, our findings validate the selected ROS-scavenging bacteria as coral probiotics that could help corals resist thermal stress on a short timescale. Additionally, our data contribute to our understanding of the potential interactions between different members of the coral holobiont and the use of probiotics as tools to aid coral restoration efforts. [ABSTRACT FROM AUTHOR]

Ulva prolifera is the most common specie causative to green tide, and its growth is sensitive to temperature stress. However, the mechanisms of U. prolifera response to temperature stress remain elusive. In this study, high temperature (36 °C) stimulus promoted the death of unformed cell wall protoplasts and delayed the division of formed cell wall protoplasts, while low-temperature (4 °C) stimulus did not, suggesting that the mechanisms of the response of U. prolifera to high and low-temperature stresses are different. Transcriptome results show that proliferation-related genes were differentially expressed under high and low-temperature stresses, especially the proliferating cell nuclear antigen (PCNA) and cyclins (CYCs). Subsequently, the interaction between PCNA and Cyclin A was confirmed by Co-immunoprecipitation, yeast two-hybrid, and so on. Furthermore, high- and low-temperature stresses induced the expression of PCNA and Cyclin A in varying of degrees, and activated extracellular signal-regulated kinase (ERK) signal pathway. These results suggest, PCNA, Cyclin A, and ERK signal pathway played important roles in the resistance of U. prolifera to temperature stress. Interestingly, high-temperature stress induced an increase of miR-2916 in abundance, and exhibiting reverse expression of PCNA; and PCNA was target gene of miR-2916, suggesting that miR-2916 protected U. prolifera from high-temperature stress via post-transcriptionally regulation of PCNA. This study laid a foundation for understanding the function of PCNA and Cyclin A, moreover, it has a guiding significance to explore the mechanisms of the response to temperature stress from proliferation-related genes regulatory networks in U. prolifera. [ABSTRACT FROM AUTHOR]

The geographical range of schistosomiasis is affected by the ecology of schistosome parasites and their obligate host snails, including their response to temperature. Previous models predicted schistosomiasis' thermal optimum at 21.7°C, which is not compatible with the temperature in sub-Saharan Africa (SSA) regions where schistosomiasis is hyperendemic. We performed an extensive literature search for empirical data on the effect of temperature on physiological and epidemiological parameters regulating the free-living stages of S. mansoni and S. haematobium and their obligate host snails, i.e., Biomphalaria spp. and Bulinus spp., respectively. We derived nonlinear thermal responses fitted on these data to parameterize a mechanistic, process-based model of schistosomiasis. We then re-cast the basic reproduction number and the prevalence of schistosome infection as functions of temperature. We found that the thermal optima for transmission of S. mansoni and S. haematobium range between 23.1–27.3°C and 23.6–27.9°C (95% CI) respectively. We also found that the thermal optimum shifts toward higher temperatures as the human water contact rate increases with temperature. Our findings align with an extensive dataset of schistosomiasis prevalence in SSA. The refined nonlinear thermal-response model developed here suggests a more suitable current climate and a greater risk of increased transmission with future warming for more than half of the schistosomiasis suitable regions with mean annual temperature below the thermal optimum. Author summary: In this research, we explored the complex interplay between temperature and the transmission risk of schistosomiasis, a parasitic disease currently affecting over two hundred million people, predominantly in SSA. We developed a novel mathematical model accounting for the multiple positive and negative ways temperature affects the free-living stages of the parasite and its obligate, non-human host, i.e., specific species of freshwater snails. Our models show that schistosomiasis transmission risk peaks at temperatures 1–6°C higher than previously estimated. This indicates that the impact of climate change on schistosomiasis transmission might be more extensive than previously thought, affecting a wide geographic range where mean annual temperatures are currently below the optimal temperature. Our model projections are consistent with the observed temperatures in locations of SSA where schistosomiasis is endemic and data on infection prevalence in the human population are available. These findings suggest that the current climate is conducive to schistosomiasis transmission, and future warming could escalate the risk further, emphasizing the need for targeted interventions in these regions. [ABSTRACT FROM AUTHOR]

Simple Summary: Stress in beef cattle occurs throughout all management practices. The goal of a cow–calf producer is to produce one calf per cow a year; thus, stressors in these management systems can disrupt this desire. When homeostasis is disturbed, the efficiency of a beef cow decreases, which may lead to reproductive deficiencies, reduced daily intake, and a decreased body condition score. Therefore, this decline in production efficiency may cause a loss in the profitability of the operation. The goal of this review is to address the stressors inherent in beef cattle management systems to provide producers with insight into the best ways to mitigate beef cattle stress. Stressors are directly related to major events throughout the beef cattle production cycle. Understanding the impact stressors have on productive outcomes is critical for the efficient implementation of management strategies. Such stressors include environmental extremes, nutritional deprivation, and common management procedures. Environmental extremes such as thermal stress can disturb gestating cows' normal physiological responses, hindering reproductive efficiency. Thermal stress during the breeding season can affect embryo development causing a decrease in conception rates, although adjusting the scheduling of breeding activities can minimize losses. Additionally, suboptimal nutrition may negatively impact reproductive performance if management strategies including modifying seasonal grazing practices are not implemented. As gestation progresses, nutrient requirements increase; thus, without appropriate dietary management, poor calf performance, the loss of the body condition score, and reduced reproductive performance may result. While weaning is a common management procedure, this event is another major stress within the production system. Applying efficient strategies such as creep feeding or two-step weaning to mitigate weaning stress can maximize production efficiency. This review will explore in-depth the stressors associated with production events in the beef cattle industry and give insight into researched management strategies targeting these stressors that will improve the sustainability of the production system. [ABSTRACT FROM AUTHOR]

The article titled "Tree Physiology" discusses the impact of climate change on gas exchange in tropical forests. It emphasizes the importance of vapor pressure deficit (VPD) in determining the photosynthetic temperature optimum in tropical trees. The study conducted on 42 species of trees in Panama concludes that VPD is the main driver of photosynthesis reduction in tropical trees, surpassing the influence of temperature alone. The authors highlight the need to consider VPD in accurately predicting carbon stock and forest growth in tropical forests under future climates. This research provides valuable insights into the potential effects of climate change on tropical forests and calls for further investigation in this area. [Extracted from the article]

Global warming affects the metabolism of ectothermic aquatic breathers forcing them to migrate and undergo high‐latitudinal distribution shifts to circumvent the temperature‐induced mismatch between increased metabolic demand and reduced water oxygen availability. Here the authors examined the effects of temperature on oxygen consumption rates in an Arctic stenotherm, the Greenland halibut Reinhardtius hippoglossoides, and calculated the optimal temperature for maximum aerobic scope, AS(Topt,AS), which was found to be 2.44°C. They also investigated cardiac performance as limiting the oxygen transport chain at high temperatures by measuring maximum heart rate (fHmax) over acute temperature increases and found various metrics related to fHmax to be at least 3.2°C higher than Topt,AS. The authors' measured Topt,AS closely reflected in situ temperature occurrences of Greenland halibut from long‐term tagging studies, showing that AS of the species is adapted to its habitat temperature, and is thus a good proxy for the species' sensitivity to environmental warming. The authors did not find a close connection between fHmax and Topt,AS, suggesting that cardiac performance is not limiting for the oxygen transport chain at high temperatures in this particular Arctic stenotherm. The authors' estimate of the thermal envelope for AS of Greenland halibut was from −1.89 to 8.07°C, which is exceptionally narrow compared to most other species of fish. As ocean temperatures increase most rapidly in the Arctic in response to climate change, and species in these areas have limited possibility for further poleward‐range shifts, these results suggest potential severe effects of global warming on Arctic stenotherms, such as the Greenland halibut. The considerable economic importance of the species raises concerns for future fisheries and species conservation of Arctic stenotherms in the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

Atlantic tarpon Megalops atlanticus are highly migratory sportfish that support recreational fisheries throughout their range. In US waters, juveniles can be found in coastal and estuarine habitats along the Gulf of Mexico and Atlantic seaboard, with temperature limiting their northern latitudinal distribution. Juveniles may overwinter in these areas during the first several years of life. Low temperatures are known to cause mortality in adults, but the challenges of temperature are less understood for juveniles. Furthermore, salinity, which can change dramatically in these habitats, may have a synergistic effect with temperature. To examine the physiological effects of temperature and salinity on juvenile tarpon, wild fish were acclimated to a range of conditions that potentially occur in the northern range of their estuarine habitats. The haematology of juvenile tarpon was examined in two salinity (≤2 and ≥30 ppt) and temperature (15 and 25°C) treatments, followed by a low‐temperature tolerance test. After 2 weeks in treatment conditions, blood samples were analysed for haematocrit, pH, red blood cell concentration, haemoglobin content and plasma osmolality. Increased plasma osmolality was observed in fish at low temperature (15°C compared to 25°C) and at high salinity (≥30 ppt compared to ≤2 ppt). Blood pH was increased at 15°C compared to 25°C, with the highest pH at 15°C and low salinity. Haemoglobin, haematocrit and red blood cell concentration were higher at 25°C than 15°C, with haemoglobin lowest at 15°C and low salinity. For the low‐temperature tolerance test, all fish were acclimated to 15°C for 2 weeks, then transferred to separate tanks where temperature was gradually decreased at 0.9 ± 0.1°C/h until fish lost equilibrium. Fish at low salinity lost equilibrium more rapidly (1 ppt, 12.65 ± 0.46°C) than fish at high salinity (30 ppt, 11.26 ± 0.14°C). The results indicate juvenile tarpon are susceptible to low temperature, which is exacerbated by low salinity, findings useful in the assessment of juvenile tarpon overwintering habitat. [ABSTRACT FROM AUTHOR]

Atlantic salmon Salmo salar are experiencing widespread population declines, and reductions in growth and survival in the marine environment are contributing factors. Our aims were to estimate marine food consumption of adult salmon and to determine how energetics would be directly affected by the increased ocean temperatures associated with climate change. We tagged previous spawners on outward migration (body size 76–119 cm) with archival tags and used a bioenergetic model to combine in situ temperature recordings with individual data on body growth. Average energy consumption was estimated to be 331–813 kJ per day, which is equivalent to 5–11 prey fish with an average body mass of ca. 15 g. Energy content of prey was the most important factor determining food consumption required to maintain growth. Conversely, the increases in ocean temperatures expected with climate change were predicted to have limited physiological effects on energy budgets and limited impact on the food consumption needed to maintain growth. We conclude that climatic warming will impact Atlantic salmon primarily through changes in prey availability and ecosystem structure rather than the direct effects of temperature on physiological performance. [ABSTRACT FROM AUTHOR]

Temperature affects the growth and development of tobacco. With the frequent occurrence of extreme high and low temperature disasters, temperature stress has become one of the important factors restricting the normal growth and physiological functions of flue-cured tobacco. Low temperature stress and high temperature stress are currently the most common disasters in the seedling and maturity stages of flue-cured tobacco, which have a serious impact on the quality and yield of flue-cured tobacco. This article reviews the effects of temperature stress on physiological mechanisms such as growth and development, photosynthetic function, carbon and nitrogen metabolism, and antioxidant system of flue-cured tobacco. It introduced the research progress of related plant proteins and molecular mechanisms in temperature stress, and systematically summarizes the current stress resistance control measures for field temperature stress, including field management and spraying exogenous substances. At present, most agronomic interventions for temperature stress management may not be complete. It is necessary to understand the genetic, biochemical and physiological processes of different varieties in order to identify and select traits, enhance their high-temperature resistance mechanism, and cultivate high-temperature resistant flue-cured tobacco varieties. Looking forward to future research on temperature stress in flue-cured tobacco, including exploring local germplasm resources, cultivating heat-resistant varieties, utilizing methods such as multi omics or cross omics to deeply explore the response mechanism of temperature stress in flue-cured tobacco, developing predictive research on temperature stress in flue-cured tobacco, and developing targeted management measures for stress resistance cultivation, in order to provide scientific support for the prevention of climate disasters and the enhancement of agricultural disaster reduction efficiency for flue-cured tobacco. [ABSTRACT FROM AUTHOR]

Over the past 30 years, climate change has taken one of the leading places among the ten main causes of death due to natural disasters. Rising temperatures have been shown to increase emergency department admissions for a wide range of kidney diseases, including acute kidney injury (AKI), chronic kidney disease, kidney stones, and urinary tract infections. The occupational effect of heat stress is also associated with AKI, which can quickly progress to acute kidney failure with high mortality. The basis of the pathogenetic mechanisms of heat-induced AKI is a decrease in the circulating blood volume and electrolyte disturbances due to increased perspiration. Water evaporation from the surface of the skin contributes to dehydration with an increase in serum osmolarity. In response to this, vasopressin is activated, the specific gravity of urine increases, and the amount of urine decreases. The glomerular filtration rate progressively decreases. Hypokalemia develops, which changes to hyperkalemia within 12 hours. Tubular endothelium is damaged, which leads to microthrombosis of afferent and efferent renal arteries, the development of an inflammatory response, and exhaustion of the renal interstitium. Possible rhabdomyolysis and myoglobinemia with subsequent tubular obstruction worsen existing kidney damage. According to the leading mechanism of damage, there are two types of acute heat damage to the kidneys: classical rhabdomyolysis and acute interstitial nephritis. Although modern medical advances have contributed to the development of effective treatment and management strategies (rapid cooling, extracorporeal detoxification methods, etc.), mortality in kidney damage due to general overheating has decreased slightly over the past decades. For health care and industry researchers, it is necessary to identify the harmful occupational conditions that lead to heat stress nephropathy and to develop certain occupational safety strategies. [ABSTRACT FROM AUTHOR]

Adamussium colbecki is a scallop endemic of the Antarctic Ocean, the only modern survivor of the Adamussiini tribe and one of the few bivalves living in polar environments. Compared with other Antarctic animals, very little is known concerning the evolutionary adaptations which allow this species to thrive at sub-zero temperatures. Due to its local abundance and sensitivity to environmental changes, A. colbecki is an interesting model for studying the effects of pollution and climate change in the Antarctic Ocean. Here, we report, for the first time, the application of transcriptomic tools to the study of the effects of a short-to-medium term exposure to a +1.5 °C water temperature increase on three tissues. Although this approach did not highlight any significant change in response to thermal stress, we observed slight alterations in energetic metabolism and nutrient adsorption in the digestive gland, most likely linked with stabling in experimental tanks. The results of our study suggest that A. colbecki may be particularly vulnerable to the effects of climate change due to its complete inability to adapt to temperature increase at the transcriptomic level. [ABSTRACT FROM AUTHOR]

Body size–dependent physiological effects of temperature influence individual growth, reproduction, and survival, which govern animal population responses to global warming. Considerable knowledge has been established on how such effects can affect population growth and size structure, but less is known of their potential role in temperature‐driven adaptation in life‐history traits. In this study, we ask how warming affects the optimal allocation of energy between growth and reproduction and disentangle the underlying fitness trade‐offs. To this end, we develop a novel dynamic energy budget integral projection model (DEB–IPM), linking individuals' size‐ and temperature‐dependent consumption and maintenance via somatic growth, reproduction, and size‐dependent energy allocation to emergent population responses. At the population level, we calculate the long‐term population growth rate (fitness) and stable size structure emerging from demographic processes. Applying the model to an example of pike (Esox lucius), we find that optimal energy allocation to growth decreases with warming. Furthermore, we demonstrate how growth, fecundity, and survival contribute to this change in optimal allocation. Higher energy allocation to somatic growth at low temperatures increases fitness through survival of small individuals and through the reproduction of larger individuals. In contrast, at high temperatures, increased allocation to reproduction is favored because warming induces faster somatic growth of small individuals and increased fecundity but reduced growth and higher mortality of larger individuals. Reduced optimum allocation to growth leads to further reductions in body size and an increasingly truncated population size structure with warming. Our study demonstrates how, by incorporating general physiological mechanisms driving the temperature dependence of life‐history traits, the DEB–IPM framework is useful for investigating the adaptation of size‐structured organisms to warming. [ABSTRACT FROM AUTHOR]

This study was designed to investigate about species diversity of soil mollusks in Shemiranat county. The country was divided into 10 sampling stations and the collected samples were identified morphologically and systematically according to the certified identification keys. Results showed the significant effect of temperature and relative humidity on the abundance of the soil mollusks. There were no samples collected in cold months, but in warm seasons, August had the most numerous samples, and March showed the lowest abundance. In this study, a total of 94 samples belonging to 10 species under 9 genera and 8 families were identified as follows: Helix lucorum (Helicidae), Cernuella neglecta, Monacha cantiana and M. parumcincta (Hygromidae), Succinea putris (Succineidae), Chondrula tridens (Enidae), Planorbis intermixtus (Planorbidae), Deroceras tritulatum (Agriolimacidae), Ambigolimax valentianus (Limacidae) and Arion fuscus (Arionidae). P. intermixtus was the most abundant species among the collected samples and S. putris had the lowest density. [ABSTRACT FROM AUTHOR]

Copyright of ESPOCH Congresses: The Ecuadorian Journal of S.T.E.A.M. is the property of Knowledge E DMCC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Chronic or acute exposure to 3 °C did not negatively affect brook char (vs. 14 °C). • Fish condition was better after long-term acclimation to 3 °C than to 14 °C. • Cu bioaccumulation in fish gills was not affected by acclimation temperature. • Cu inhibited Na+ influx and NH 3 excretion, promoted Cl− loss in juvenile brook char. • Sensitivity to Cu was greater in the 14 °C- than in 3 °C-acclimated fish. Freshwater fish that are acutely exposed to copper (Cu) can experience disturbances of ion regulation and ammonia excretion. Temperature has been shown to affect Cu bioaccumulation and toxicity in fish, but the focus has largely been on warm temperature effects. Yet, acclimation of freshwater fish to near-freezing temperatures encountered during the winter of temperate regions can challenge fish condition and physiology, including ion regulation. Thus, temperate freshwater fish might be particularly sensitive to Cu in the winter. We investigated how winter cold affects acute Cu bioaccumulation and toxicity in juvenile brook char (Salvelinus fontinalis). Following gradual acclimation to cold temperature (-2 °C/week from 14 °C, then 4 weeks at 3 °C) vs. a warmer temperature around the species thermal optimum (14 °C for 9 weeks), and following a cold challenge (-3 °C/day from 14 °C, then 24 h at 3 °C) vs. a cold acclimation (-2 °C/week from 14 °C, then 13 weeks at 3 °C), we measured gill-Cu bioaccumulation, net fluxes of ammonia (NH 3), chloride (Cl−) and net and unidirectional fluxes of sodium (Na+) over a 30-h Cu exposure. Overall, winter cold did not appear to be challenging to brook char, as cold-acclimated fish had a higher fish condition and showed no sign of ion regulation impairment or increased Cu sensitivity. Contrary to our prediction, we found that Cu bioaccumulation over a 30-h Cu exposure was not significantly affected by acclimation temperature. Effects of temperature on Cu physiological effects were relatively limited (mainly on inhibition of Na+ influx and of NH 3 excretion), with slightly greater effects observed in 14 °C-acclimated fish. [ABSTRACT FROM AUTHOR]

Background and purpose: CaV1.2 channels contribute to action potential upstroke in pacemaker cells, plateau potential in working myocytes, and initiate excitation-contraction coupling. Understanding drug action on CaV1.2 channels may inform potential impact on cardiac function. However, literature shows large degrees of variability between CaV1.2 pharmacology generated by different laboratories, casting doubt regarding the utility of these data to predict or interpret clinical outcomes. This study examined experimental factors that may impact CaV1.2 pharmacology. Experimental approach: Whole cell recordings were made on CaV1.2 overexpression cells. Current was evoked using a "step-step-ramp" waveform that elicited a step and a ramp current. Experimental factors examined were: 1) near physiological vs. room temperature for recording, 2) drug inhibition of the step vs. the ramp current, and 3) Ca2+ vs. Ba2+ as the charge carrier. Eight drugs were studied. Key results: CaV1.2 current exhibited prominent rundown, exquisite temperature sensitivity, and required a high degree of series resistance compensation to optimize voltage control. Temperature-dependent effects were examined for verapamil and methadone. Verapamil's block potency shifted by up to 4X between room to near physiological temperature. Methadone exhibited facilitatory and inhibitory effects at near physiological temperature, and only inhibitory effect at room temperature. Most drugs inhibited the ramp current more potently than the step current—a preference enhanced when Ba2+ was the charge carrier. The slopes of the concentration-inhibition relationships for many drugs were shallow, temperature-dependent, and differed between the step and the ramp current. Conclusions and implications: All experimental factors examined affected CaV1.2 pharmacology. In addition, whole cell CaV1.2 current characteristics—rundown, temperature sensitivity, and impact of series resistance—are also factors that can impact pharmacology. Drug effects on CaV1.2 channels appear more complex than simple pore block mechanism. Normalizing laboratory-specific approaches is key to improve inter-laboratory data reproducibility. Releasing original electrophysiology records is essential to promote transparency and enable the independent evaluation of data quality. [ABSTRACT FROM AUTHOR]

Resolving the combined effect of climate warming and exploitation in a food web context is key for predicting future biomass production, size‐structure and potential yields of marine fishes. Previous studies based on mechanistic size‐based food web models have found that bottom‐up processes are important drivers of size‐structure and fisheries yield in changing climates. However, we know less about the joint effects of 'bottom‐up' and physiological effects of temperature; how do temperature effects propagate from individual‐level physiology through food webs and alter the size‐structure of exploited species in a community? Here, we assess how a species‐resolved size‐based food web is affected by warming through both these pathways and by exploitation. We parameterize a dynamic size spectrum food web model inspired by the offshore Baltic Sea food web, and investigate how individual growth rates, size‐structure, and relative abundances of species and yields are affected by warming. The magnitude of warming is based on projections by the regional coupled model system RCA4‐NEMO and the RCP 8.5 emission scenario, and we evaluate different scenarios of temperature dependence on fish physiology and resource productivity. When accounting for temperature‐effects on physiology in addition to on basal productivity, projected size‐at‐age in 2050 increases on average for all fish species, mainly for young fish, compared to scenarios without warming. In contrast, size‐at‐age decreases when temperature affects resource dynamics only, and the decline is largest for young fish. Faster growth rates due to warming, however, do not always translate to larger yields, as lower resource carrying capacities with increasing temperature tend to result in decline in the abundance of larger fish and hence spawning stock biomass. These results suggest that to understand how global warming affects the size structure of fish communities, both direct metabolic effects and indirect effects of temperature via basal resources must be accounted for. [ABSTRACT FROM AUTHOR]

A major goal and challenge in (eco)toxicology is understanding and predicting the accumulation and impacts of contaminant stressors. However, QSARs may be oversimplistic as relevant contaminant characteristics need careful consideration, and they do not account for various physiological and environmental processes that are known to influence contaminant kinetics and dynamics. Detailed TK studies are another useful way to model contaminant bioaccumulation using empirical data from laboratory experiments or field monitoring. Bioaccumulation or biomagnification models describe the process of contaminant uptake in organisms from their environment or from dietary sources within the food web. [Extracted from the article]

Copyright of Journal of Northwest A & F University - Natural Science Edition is the property of Editorial Department of Journal of Northwest A&F University (Natural Science Edition) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thermoregulation in running and cycling is well characterized but little is known about thermoregulation during swimming. This study aimed to determine the effect of different environmental conditions on physiological and perceptual measures and training performance during outdoor training in elite and sub-elite swimmers. Nine elite and ten sub-elite swimmers undertook training in an outdoor pool in COOL (wet bulb globe temperature [WBGT]=14.7°C) and WARM (WBGT=23.0°C) or COLD (WBGT=10.3°C) and HOT (WBGT=27.0°C) environmental conditions, respectively. Environmental conditions, gastrointestinal temperature (Tgi), skin temperature (Tsk), thermal comfort, thermal sensation and performance times were recorded throughout training sessions and analysed using repeatedmeasures ANOVA with alpha 0.05. Ambient temperature differed between COOL and WARM (7.9 °C, p<0.001), and COLD and HOT (14.5 °C, p<0.001). Tsk (p<0.001, ELITE: 2.8 °C, SUB-E: 4.5 °C) and thermal sensation (ELITE: p=0.012, 0.5 AU; SUB-E: p=0.028, 0.6 AU) were higher in WARM/HOT conditions compared to COOL/COLD but Tgi was not different. There were small improvements in swimming performance during WARM/HOT trials in elite and sub elite swimmers (ELITE: -1.7%, d=0.2; SUB-E: -3.2%, d=0.2). Skin temperature and thermal sensation vary dependent on ambient temperature despite consistent water temperature, with a small to moderate improvement in the quality of training during hot/warm compared to cold/cool seasonal conditions. Therefore, scheduling sprint training in the afternoon, training indoors in a controlled environment or training in a location with a warmer climate could increase training performance during periods of cold/cool weather for swimmers who train in outdoor pools. Additionally, using garments that warm or maintain skin temperature such as heating jackets or wetsuits may be an effective strategy for increasing sprint swimming performance in cool/cold climates. [ABSTRACT FROM AUTHOR]

Coffea arabica, an economically important crop, accounts for most of the coffee consumed globally. Increasing temperature due to climate change can cause a decrease in productivity in many crops, including coffee plants. The maximum temperature at which damage is induced has been reported for many crops, but it remains unclear in coffee plants. Here, we investigated the effect of different temperatures and the physiological damage induced by heat stress using both leaf disks and intact plants of Coffea arabica 'Typica'. In the experiment using intact plants, we observed leaf damage by a decrease in soil plant analysis development value, and an increase in electrolyte leakage after exposure to 45°C for 96 h, whereas no leaf damage was observed for 72 h. The leaf surface temperatures after exposure to 45°C for 72 and 96 h were 44.0 and 46.3°C, respectively. Thus, a tolerance threshold in leaves of C. arabica 'Typica' under heat stress are likely between 44.0 and 46.3°C. The activities of catalase (CAT) and superoxide dismutase (SOD) decreased at 45°C in both leaf disks and intact plants. The decrease in the activities of SOD and CAT under heat stress may be responsible for the increased levels of reactive oxygen species, such as O2− and H2O2, and the resulting cellular damage. Our findings provide valuable insights into the physiological responses of Coffea arabica 'Typica' to heat stress, which may contribute to the breeding and screening of tolerant cultivars in the future. [ABSTRACT FROM AUTHOR]

Heat stress has become a dominantly crucial factor in limiting wheat yields threatening global food security.Therefore, understanding the effects of temperature on phenology and the physiological traits is very crucial for plant breeders to combat increasing temperature as wheat is a cool-season crop having 15°C at the reproductive stage. In this article, we briefly review only the effects of heat stress and tolerance mechanism on wheat regarding its different aspects. We reviewed that heat stress adversely affects photosynthesis, membrane stability, grain filling, dough properties and gluten proteins, pollen fertility, fruit and/ or seed yield, and photosynthetic characteristics in flag leaves.The photosynthetic efficiency is greatly reduced by unwanted production of reactive oxygen species, denaturation of heat shock proteins, and alternation in many enzymes. [ABSTRACT FROM AUTHOR]

Temperature is a major abiotic stress factor limiting plant growth and development during the early developmental stage. Information on carinata (Brassica carinata A. Braun) traits response to low and high temperatures is necessary for breeding or selecting genotypes suited for specific ecoregions, which is limited. In the present study, 12 carinata genotypes were evaluated under low (17/09°C), optimum (22/14°C), and high (27/19°C) day/night temperatures at the early developmental stage. This study quantified temperature effects on several physiological and morphological characteristics of 12-advanced carinata lines. High-temperature plants decreased (15%) the accumulation of flavonoids and increased the nitrogen balance index by 25%. Low-temperature treatment significantly inhibited the aboveground (plant height, leaf area, number, and shoot weight) and root (length, surface area, and weight) traits. Across all genotypes, the shoot weight decreased by 55% and the root weight by 49% under low temperature. On the other hand, the maximum proportion of biomass was partitioned to roots under low temperature than at the high temperature. A poor relationship (r 2 = 0.09) was found between low- and high-temperature indices, indicating differences in trait responses and tolerance mechanisms. AX17004 and AX17009 with higher root to shoot ratios might be suitable for late planting windows or regions with low-temperature spells. The two genotypes (AX17015 and AX17005) accumulated higher biomass under low- and high-temperature treatments can be used for planting in later summer or early winter. The identified low- and high-temperature stress-tolerant carinata genotypes could be a valuable resource for increasing stress tolerance during the early developmental stage. [ABSTRACT FROM AUTHOR]

We have measured the resistance R(T, I, Bext) of a superconducting transition edge sensor over the entire transition region on a fine scale, producing a four-dimensional map of the resistance surface. The dimensionless temperature and current sensitivities (a ≡ ∂ log R/∂ log T|I and b ≡ ∂ log R/∂ log I|T) of the TES resistance have been determined at each point. a and b are closely related to the sensor performance, but show a great deal of complex, large amplitude fine structure over large portions of the surface that is sensitive to the applied magnetic field. We discuss the relation of this structure to the presence of Josephson "weak link" fringes. [ABSTRACT FROM AUTHOR]

Temperature is critical in regulating virtually all biological functions in fish. Low temperature stress (cold shock/stress) is an often‐overlooked challenge that many fish face as a result of both natural events and anthropogenic activities. In this study, we present an updated review of the cold shock literature based on a comprehensive literature search, following an initial review on the subject by M.R. Donaldson and colleagues, published in a 2008 volume of this journal. We focus on how knowledge on cold shock and fish has evolved over the past decade, describing advances in the understanding of the generalized stress response in fish under cold stress, what metrics may be used to quantify cold stress and what knowledge gaps remain to be addressed in future research. We also describe the relevance of cold shock as it pertains to environmental managers, policymakers and industry professionals, including practical applications of cold shock. Although substantial progress has been made in addressing some of the knowledge gaps identified a decade ago, other topics (e.g., population‐level effects and interactions between primary, secondary and tertiary stress responses) have received little or no attention despite their significance to fish biology and thermal stress. Approaches using combinations of primary, secondary and tertiary stress responses are crucial as a research priority to better understand the mechanisms underlying cold shock responses, from short‐term physiological changes to individual‐ and population‐level effects, thereby providing researchers with better means of quantifying cold shock in laboratory and field settings. [ABSTRACT FROM AUTHOR]

The increase in carbon dioxide (CO2) atmospheric levels contributes to the rise in temperature and ocean acidification; consequently, it directly impacts coral reefs. The increase in seawater temperature is the primary factor that causes the collapse of coral-algal symbiosis, which can be followed by coral death and, generally, ocean acidification impairs biogenic calcification and promotes dissolution of carbonate substrata. These harmful effects on corals associated with the continuous increase in CO2 atmospheric levels raise widespread concerns about the coral reef decline, intensifying the efforts to understand/monitor their effects on these organisms. The objective of this study was to evaluate the physiological effect of temperature increase, water acidification (i.e. decrease in pH), and their effects combined (temperature increase with water acidification), through the reflectance analyses and maximum photosynthetic capacity of zooxanthellae (Fv/Fm) in two coral species: Millepora alcicornis and Mussismilia harttii. Fragments of four large colonies of each specie were collected, fragmented, and submitted to four different treatments for 15 days: (i) control treatment (under identical temperature and pH conditions observed in the sampling seawater site), (ii) temperature treatment (with an increase temperature of around ≅2ºC); (iii) water acidification treatment (with a decrease of nearly 0.3 in pH); and (iv) a treatment of combined effects from water temperature rising and acidification. Spectral reflectance and Fv/Fm were measured from samples of these species in a marine mesocosm. Data of reflectance, first and second-order derivative, area under the curve, full width at half maximum (FWHM), depth values and the Fv/Fm were used to classify the coral species and treatments through the linear discriminant analysis (LDA). Coral samples were exposed to the increased temperature bleached, whilst decreased pH caused a slight reduction in reflectance albedo with minimal effects on Fv/Fm. The combined factors (treatment iv) triggered a bleaching response, presenting spectral reflectance and colouring patterns similar to those observed in bleached corals, especially for M. alcicornis. The two-way ANOVA indicated statistically meaningful spectral differences between treatments for the second-order derivatives at 634 nm and for Fv/Fm values. However, there was no statistically meaningful interaction effect due to the treatment type and coral species response for the second-order derivative at 670 nm and to the Fv/Fm values. LDA classified the corals' species and the corals in different treatment, using their spectral responses and Fv/Fm results, with high accuracy (96.7% and 73.3%, respectively), reinforcing its application for coral physiology evaluation and species classification. The control and combined groups achieved the best classification scores, with only one misclassification. [ABSTRACT FROM AUTHOR]

SUMMARY: Studies on the effects of temperature on physiological processes are essential to model macroalgae biogeographic distribution. Tetrasporophytes of Hypnea pseudomusciformis were collected from three floristic provinces (tropical, transition and warm temperate) along the Brazilian coast (~3.000 km), representing three ecotypes. Specimens were cultured under 20°C, 24°C, 28°C and 32°C for 21 days, then physiological parameters (growth rates, photosynthesis and pigments content) were analyzed. H. pseudomusciformis specimens tolerated a temperature variation from 20°C to 32°C. However, all ecotypes displayed a significant decrease in physiological performance at 32°C in all parameters analyzed. We hypothesized that the H. pseudomusciformis ecotype from the tropical province is already living at its thermal physiological limit, reaching its maximum growth only in the winter months (June to September), whereas a warm temperate ecotype reaches maximum growth in the summer months (December to March). This wide thermal optimum may be the reason for the widespread distribution of this species along the Brazilian coast, allowing it to occupy different thermal environments. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the difference in heart rate and core temperature during aerobic exercise between two forms of dehydration: exerciseinduced (EI) and fluid restricted (FR). Twenty-two subjects (N = 22; 83.35 ± 13.92 kg) completed the current study, performing a familiarization session, a pre-experimental exercise session, and two exercise testing sessions. The EI exercise trial (81.52 ± 13.72 kg) was conducted after performing exercise in a hot environment to lose three to four percent of body weight and partial rehydration. The FR exercise trial (81.53 ± 14.14 kg) was completed after 12 hours of fluid restriction. During both exercise sessions, subjects pedaled against a set resistance of 130 watts for 30 minutes. The main effect of hydration on Tc was significant, F(1, 18) = 4.474, p = .049, ηp² = .199 (Figure 2) with core temperature being greater during the FR trial compared to the EI trial (FR = 37.58 ± .06°C vs. EI = 37.31 ± .11°C). No significant interaction was found between hydration and time for HR, F(2, 42) = 0.120, p = .887, ηp² = .006. The main effect of time on HR was significant, F(2, 42) = 119.664, p < .001, ηp² = .851. Fluid restriction was associated with an increase in core temperature. An increased core temperature may negatively influence performance, and care should be taken to ensure proper hydration. [ABSTRACT FROM AUTHOR]

Concrete is increasingly utilized in the construction field in Southern Nevada. This area has an arid and hot summer and freezing cold winter conditions. These extreme conditions affect the properties of fresh concrete, which can cause cracking. Hot weather conditions may adversely affect both fresh and hardened concrete properties. Even though practices can minimize the detrimental effects, good quality control of fresh concrete, from mixing to finishing, is crucial under hot weather conditions. The objective of the present study is to evaluate the seasonal consistency of concrete quality, considering strength and slump properties. Another objective of this research is to determine the relationship between the seasonal air temperature variations and those of freshly batched concrete. Results indicate that strength and slump remain constant with varying air and concrete temperatures during pour. Additionally, during the hot season (air temperature above 27 °C (80 °F)), fresh concrete's temperature is lower than the air's temperature, in contrast during the cold season (air temperature below 16 °C (60 °F)), fresh concrete's temperature is higher than the air's temperature. Fresh concrete temperature and air temperature are similar in the range of 60 to 80 °F. Therefore, to limit the use of additional water or admixtures it is recommended to pour concrete when the air temperature is in the range of 16° and 27 °C (60 to 80 °F). [ABSTRACT FROM AUTHOR]

Background: Current findings on the impact of weather conditions on osteoarthritis (OA) and rheumatoid arthritis (RA) are sparse and not conclusive. This study aimed to investigate the relationship between temperature change and OA/RA admission.Methods: Daily OA/RA admission, meteorological data and pollutants from 1 January 2014 to 31 December 2017 in Hefei, China, were collected. We quantified the relationship between ambient temperature and OA/RA admission using a distributed lag nonlinear model (DLNM). Stratified analyses by gender and age were also examined.Results: Temperature decrease was significantly associated with RA admission (25th percentile of temperature versus 50th percentile of temperature), with the acute and largest effect at current days lag (RR: 1.057, 95%CI: 1.005-1.111). However, no significant association between temperature and OA admission was observed. When conducting subgroup analyses by individual characteristics, we found that females and patients aged 41-65 years were more vulnerable to temperature decrease than males, patients aged 0-40 and ≧66 years, respectively.Conclusions: This study suggested that temperature decrease was a risk factor for increases in RA admission. Females and patients aged 41-65 years were particularly vulnerable to the effect of temperature decrease. [ABSTRACT FROM AUTHOR]

Amphibians may be more vulnerable to climate-driven habitat modification because of their complex life cycle dependence on land and water. Considering the current rate of global warming, it is critical to identify the vulnerability of a species by assessing its potential to acclimate to warming temperatures. In many species, thermal acclimation provides a reversible physiological adjustment in response to temperature changes, conferring resilience in a changing climate. Here, we investigate the effects of temperature acclimation on the physiological performance of tadpoles of a stream-breeding savanna tree frog (Bokermannohyla ibitiguara) in relation to the thermal conditions naturally experienced in their microhabitat (range: 18.8–24.6°C). We quantified performance measures such as routine and maximum metabolic rate at different test (15, 20, 25, 30, and 34°C) and acclimation temperatures (18 and 25°C). We also measured heart rate before and after autonomic blockade with atropine and sotalol at the respective acclimation temperatures. Further, we determined the critical thermal maximum and warming tolerance (critical thermal maximum minus maximum microhabitat temperature), which were not affected by acclimation. Mass-specific routine and mass-specific maximum metabolic rate, as well as heart rate, increased with increasing test temperatures; however, acclimation elevated mass-specific routine metabolic rate while not affecting mass-specific maximum metabolic rate. Heart rate before and after the pharmacological blockade was also unaffected by acclimation. Aerobic scope in animals acclimated to 25°C was substantially reduced, suggesting that physiological performance at the highest temperatures experienced in their natural habitat is compromised. In conclusion, the data suggest that the tadpoles of B. ibitiguara , living in a thermally stable environment, have a limited capacity to physiologically adjust to the highest temperatures found in their micro-habitat, making the species more vulnerable to future climate change. [ABSTRACT FROM AUTHOR]

An editorial is presented on the Effect of canopy temperature on physiological processes of grass pea as influenced by seed priming and foliar fertilization . The article discusses that Variations in atmospheric temperature have become a major concern with respect to agricultural production; and Plants being poikilothermic in nature, any change in temperature summons change in canopy temperature, inevitably affecting their growth and productivity.

Robust resistivity against electrical cycling at not only ambient conditions but also enhanced temperatures is an essential requirement for high-end actuator applications. In this study, the temperature and electric field dependence of unipolar fatigue behaviors of CaZrO3-modfied (K, Na)NbO3 lead-free piezoceramics were investigated. The space charge accumulation during unipolar cycling is responsible for the build-up of internal bias field, the dynamics of which with respect to temperature and driving field can be described using a model based on Maxwell-Wagner relaxation process. Besides, clamping of domain walls can be inferred by comparing the large and small signal permittivity. Most intriguingly, the unipolar strain exhibits a fatigue-free behavior even at elevated temperatures, rendering the material exceptionally suitable for actuator applications. [ABSTRACT FROM AUTHOR]

Climatic stress affects various physiological functions in the body and has a negative effect on livestock growth, health and production. Heat stress of high intensity and duration, causes metabolic disruptions, oxidative stress, decrease nutrient intake and immuno-suppression resulting in infections and death. Animals are found to cope up with the adverse effects of stress when the nutritional requirements are not compromised. Challenged by physiological reactions to heat stress, dietary requirements of macro minerals may differ from requirements in thermoneutral environment. Dietary minerals are an integral part of all biological functions in the animal body The thermal stress imposes some unique metabolic conditions that require elevated dietary cation anion difference, specifically dietary sodium and potassium. Under such circumstances, in order to sustain productivity, suitable nutritional interventions such as dietary cation anion difference (DCAD) should be adopted, with the objective of increasing the dry matter intake (DMI), improve blood buffering, stabilizing ruminal pH and thereby bring about beneficial influence on growth and production. [ABSTRACT FROM AUTHOR]

The majority of our understanding of the effects of climate change on coral reef fishes are currently based on studies of small-bodied species such as damselfishes. By contrast, we know little about the potential impacts of ocean warming on larger species of herbivorous and detritivorous reef fish, despite them being a critical functional group and an essential source of food protein for millions of people. In addition, we know little of the role of habitat in determining species' thermal sensitivity and the legitimacy of extrapolating thermal performance across closely-related species from different habitat types. Here we test the effect of exposure to increased water temperature during juvenile development on key physiological and behavioral traits of two species of rabbitfish typically associated with different habitats: Siganus doliatus (reef-associated) and S. lineatus (estuarine). Wild-caught juveniles were reared for 14 weeks at temperatures representing present-day ambient conditions (28.0 °C), late-summer ambient conditions (30.0 °C), or those projected on reefs under future global warming scenarios (31.5 °C). We then measured the somatic (growth, condition, immune response) and behavioral (feeding rate, latency to feed and activity level) traits of individuals within each treatment to determine the sensitivity of each species to elevated water temperatures. Overall, both species showed comparatively robust levels of thermal tolerance, based on previously-documented responses of small-bodied reef fishes. However, two very different patterns emerged. The reef-associated S. doliatus showed a greater physiological response to temperature, with negative effects on hepatosomatic condition and immune function observed in individuals exposed to the 31.5 °C treatment. By contrast, there were no negative physiological effects of temperature observed in S. lineatus and instead we recorded behavioral changes, with individuals at 30 °C and 31.5 °C displaying altered feeding behavior (increased feeding rate and decreased latency to feed). These distinct responses observed between congeners are likely due to their evolutionary history and flag the potential inaccuracies that could arise from extrapolating effects of ocean warming across even closely-related species adapted to different habitats. [ABSTRACT FROM AUTHOR]

The development of insects is critically affected by temperature, which therefore plays an important role in the control of stored grain pests. Extreme temperature stress conditions lead to biological responses in mites, such as the synthesis of heat shock proteins. Tyrophagus putrescentiae (Tp) is a pest mite in stored grain that has negative effects on both economy and health. Since T. putrescentiae population dynamics are strongly influenced by temperature, in the present study we have cloned the cDNA of HSP70 and HSP90 (referred to as TpHSP70-1, TpHSP70-2 and TpHSP90) and determined their expression by fluorescence real time quantitative PCR. TpHSP70 and TpHSP90 showed high homology with similar genes in other species and the open reading frames of TpHSP70-1, TpHSP70-2 and TpHSP90 encoded proteins of 665, 661 and 718 amino acid residues, respectively. Under thermal stress, expression of TpHsp70-1 and TpHsp90 was up-regulated at higher temperatures, suggesting their role in the defense against thermal stress. [ABSTRACT FROM AUTHOR]

Typically, laboratory studies on the physiological effects of temperature are conducted using stable acclimation temperatures. Nonetheless, information extrapolated from these studies may not accurately represent wild populations living in thermally variable environments. The aim of this study was to compare the growth rate, metabolism and swimming performance of wild Atlantic salmon exposed to cycling temperatures, 16–21°C, and stable acclimation temperatures, 16, 18.5, 21°C. Growth rate, metabolic rate, swimming performance and anaerobic metabolites did not change among acclimation groups, suggesting that within Atlantic salmon's thermal optimum range, temperature variation has no effect on these physiological properties. [ABSTRACT FROM AUTHOR]

Temperature increase and its effects on fish stress physiology in the context of global warming. Despite, however, casting our net wide among our fish biology colleagues, enthusiasm for further reviews of effects of warming on fish ecology and fisheries was low. On the other hand, our physiologist colleagues were keen to contribute, perhaps because although the significance of physiology for understanding responses by fishes to warming is intuitive, many unknowns remain and this is an active area of research in the fish physiology community. The reality of global warming is now undeniable: many aquatic ecosystems are experiencing progressive increases in seasonal temperatures coupled with wider thermal variation, and an increased incidence of extreme heatwaves (Collins I et al i ., 2019; Frölicher I et al i ., 2018; IPCC, 2014). [Extracted from the article]

The establishment of seed banks is essential for the conservation of cultivated and wild plant species. Cattleya species are economically important, but many of them are at risk of extinction. In this study, we aimed to evaluate the effects of storage temperature on the physiological quality of seeds of seven congeneric species of diverse biomes from the UNOESTE-OSSSU seed bank and the lipid composition. Seeds were split into sub samples, pre-conditioned to 0.03 g H2O g DW−1 for a week over a supersaturated solution of lithium chloride at 23 ± 2 °C and maintained in rubber-sealed vessels for nine months under four storage temperatures: room temperature (23 ± 2 °C), 5 °C, –18 °C and –196 °C. Germination, the germination speed index, and viability based on a tetrazolium test were evaluated at three-month intervals. Lipid profiles were determined by GC-MS in the original seed lots. Different lipid profiles were found among species. Orchid seeds with a low water content could be stored for a short period in all conditions studied and were considered orthodox short-lived seeds. Cattleya rupestris seeds were more tolerant than the congeners to deterioration under all the storage conditions. [ABSTRACT FROM AUTHOR]

Mountain areas create specific features of local climates (by modification of air circulation, insolation, air temperature, precipitation, wind regime) and greatly affect ambient weather conditions which influence different kinds of human (climbing, skiing, walking, etc.). However, till now only few studies of human bioclimate in individual mountain ridges in Europe were done. The aim of the present study is to assess thermal stress features represented by Universal Thermal Climate Index (UTCI) in nine mountain systems in Central and Eastern Europe. 37 meteorological stations located at altitudes of 237-3580 m above sea level were considered. The data represent midday observational term and cover the period 2000-2017. Mean, highest and lowest annual thermal stress values and annual frequency of cold and heat stress days are analysed The conducted studies have demonstrated that in the examined mountain systems thermal stress conditions are dependent (though to a various extent) mostly on altitude (UTCI values and heat stress days decrease and number of cold stress days rise significantly due to increase of altitude). However, impacts of latitude and longitude is well seen only in altitude belt of 300-1000 m a.s.l. [ABSTRACT FROM AUTHOR]

The assessment of thermal stress stimuli in Poland was based on the Universal Thermal Climate Index (UTCI). Daily values of UTCI at 24 stations selected to represent the whole area of Poland at 12:00 UTC were calculated over the period 1951-2018. Various UTCI characteristics, i.e., spatial averages of daily, monthly and annual values, daily spatial contrasts (i.e., the difference between daily highest and lowest UTCI values) were defined in each of 8 bioclimatic regions of Poland. Ten-year trends for UTCI and spatial contrast values were counted and their statistical significance was analysed. A statistically significant increase in UTCI values was found in all the regions of Poland. However, contrasts in thermal stress both for Poland as a whole and in most of the regions decreased significantly, especially in the north-east of Poland, the country's coldest region. This indicates a reduction in the stimuli of thermal environment in Poland and in most of the individual regions. [ABSTRACT FROM AUTHOR]

Climate warming and biological invasions are key drivers of biodiversity change. Their combined effects on ecological communities remain largely unexplored. We investigated the direct and indirect influences of temperature on invasion success, and their synergistic effects on community structure and dynamics. Using size-structured food web models, we found that higher temperatures increased invasion success. The direct physiological effects of temperature on invasions were minimal in comparison with indirect effects mediated by changes on food web structure and stability. Warmer communities with less connectivity, shortened food chains and reduced temporal variability were more susceptible to invasions. The directionality and magnitude of invasions effects on food webs varied across temperature regimes. When invaded, warmer communities became smaller, more connected and with more predator species than their colder counterparts. They were also less stable and their species more abundant. Considering food web structure is crucial to predict invasion success and its impacts along temperature gradients. [ABSTRACT FROM AUTHOR]

In recent decades, eggshells of eggs from large-bodied reptiles have been studied by many researchers, to describe the eggshell, to compare them to extinct lineages that once inhabited our planet and also to understand how the egg provides the embryo specific conditions during incubation. In previous studies we described and characterized normal and pathologic Caiman latirostris eggshells; we also evaluated how the eggshell changes during incubation. In a study relating temperature variation and eggshell structures of successful eggs, we observed empty structures not previously described that we termed "intracascaral space". The aim of this study is to describe this structure of C. latirostris eggshells. We hypothesize about the possible functions which it would perform during incubation and for development of the embryos. [ABSTRACT FROM AUTHOR]

This paper is a proposal to embed tree-shaped vasculatures in a wall designed such that the wall withstands without excessive hot spots and peak stresses the intense heating and pressure that impinge on it. The vasculature is a quilt of square-shaped panels, each panel having a tree vasculature that connects the center with the perimeter. The vascular designs for volumetric cooling can be complemented by the shaping and distributing of channels for maximum strength and thermal performance at the same time. Numerical simulations of heat flow and thermal stresses in three directions show that it is possible to determine the optimal geometric features of configurations with radial channels and trees with radial and one level of bifurcations. The global performance is evaluated in terms of the overall thermal resistance and peak von Mises stresses. The dendritic design is superior under the studied thermal condition. [ABSTRACT FROM AUTHOR]

The dynamics of magnetization (M) reversal and relaxation as a function of temperature (T) are reported in three non-interacting NiFe ring arrays having fixed ring outer diameter and varying widths. Additionally, the dependence of M(H) loop on the angle (ϑ) between magnetic field (H) and the plane of the rings is addressed. The M(H) loops show a double step transition from onion state (OS) to vortex state (VS) at all temperatures (T=3 to 300 K) and angles (ϑ=0 to 90°). The critical reversal fields HC1 (OS to VS) and HC2 (VS to OS) show a pronounced dependence on T, ring width, and ϑ. Estimation of the transverse and vortex domain wall energies reveals that the latter is favored in the OS. The OS is also the remanent state in the smallest rings and decays with the effective energy scale (U0/T) of 50 and 32 meV/K at 10 and 300 K, respectively. The robust in-plane anisotropy of magnetization of ring assemblies is established by scaling the M(H) with ϑ. [ABSTRACT FROM AUTHOR]

Evidence of the relationship between temperature during pregnancy and human embryo mortality is limited. Most importantly, the literature lacks causal estimations and studies on early pregnancy losses. Here, we estimate the impact of early pregnancy temperature exposure on the clinically unobserved pregnancy loss rate. We use administrative data of clinically observed pregnancies from more than three decades for Hungary. We apply an empirical approach that allows us to infer the impact of temperature on the clinically unobserved pregnancy loss rate from the estimated effects on the clinically observed conception rate. The results show that exposure to hot temperatures during the first few weeks after the conception week increases the clinically unobserved pregnancy loss rate, whereas exposure to colder temperatures seems to decrease it. Importantly, the temperature-induced changes represent changes in the total number of pregnancy losses rather than a compositional change between clinically observed and clinically unobserved pregnancy losses. [ABSTRACT FROM AUTHOR]