Short-term Temperature Research Articles

Temperature effects on teleost immunity in the light of climate change.

Temperature is an important environmental modulator of teleost immune activity. Susceptibility of teleosts to temperature variation depends on the species-specific adaptive temperature range, and the activity of the teleost immune system is generally temperature-dependent. Similar to many physiological and metabolic traits of ectotherms, temperature modulates the activity of immune traits. At low temperatures, acquired immunity of many teleost species is down-modulated, and their immuno-competence mainly depends on innate immunity. At intermediate temperatures, both innate and acquired immunity are fully active and provide optimal protection, including long-lasting immunological memory. When temperatures increase and reach the upper permissive range, teleost immunity is compromised. Moreover, temperature shifts may have negative effects on teleost immune functions, in particular if shifts occur rapidly with high amplitudes. On the contrary, short-term temperature increase may help teleost immunity to fight against pathogens transiently. A major challenge to teleosts therefore is to maintain immuno-competence throughout the temperature range they are exposed to. Climate change coincides with rising temperatures, and more frequent and more extreme temperature shifts. Both are likely to influence the immuno-competence of teleosts. Nonetheless, teleosts exist in habitats that differ substantially in temperature, ranging from below zero in the Arctic's to above 40°C in warm springs, illustrating their enormous potential to adapt to different temperature regimes. The present review seeks to discuss how changes in temperature variation, induced by climate change, might influence teleost immunity.

Reconstruction of 60-year (1961–2020) surface air temperature on the Tibetan Plateau by fusing MODIS and ERA5 temperatures

The warming amplification of the Tibetan Plateau (TP) has exerted great impacts on the environment in and around the region. It is necessary to thoroughly investigate the temperature changes over the TP. However, the commonly used station observations, satellite products and reanalysis data for relevant studies suffer from deficiencies of sparse spatial distribution, limited temporal coverage and large uncertainties, respectively. This leaves the current understanding of temperature change on the TP still inadequate. Therefore, we propose a multi-source data fusion method to integrate the advantages of different data. Combining the Moderate-resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) products and station observations, this new method first obtains short-term satellite-derived surface air temperature (SAT) estimates over grids. The European Center for Medium-range Weather Forecasts ReAnalysis 5 land portion (ERA5-Land) temperature with long time range is then clustered and used as independent variables for the Bayesian Ridge Regression (BRR) model. Based on this BRR model, the temporal span of the estimated gridded satellite SAT is extended, and a fused 1-km monthly mean SAT dataset is generated over the TP from 1961 to 2020. The results indicate that the fused data generated by our proposed method has good accuracy with overall RMSE and MBE of 1.33 °C and 1.03 °C, respectively. Despite the temporal and spatial heterogeneity, the performance of the fused SATs is acceptable across seasons and geographical locations. The dataset also shows a great potential for detecting accurate long-term temperature changes across the TP. This fused SAT data owns the advantages from multiple data sources with high accuracy, good spatial continuity, fine spatial resolution and wide temporal coverage, which confirms that our fusion method can provide a favorable opportunity to explore the warming over the TP.

Time Series Temperature Forecasting by using ConvLSTM Approach, Case Study in Jakarta

Climate change has occurred in several countries, especially in tropical countries such as Indonesia. It causes extreme temperature changes in several Indonesian areas, especially Jakarta, one of the world's most populated cities. The population of Jakarta causes the activities carried out by residents to be disturbed by extreme temperature changes. In addition, drastic temperature changes also affect the energy consumption used by residents. Therefore, it is necessary to predict temperature to determine future temperature conditions so that residents can plan their activities. Temperature forecast can be done in several ways, one of which uses a machine learning approach. This research uses a deep learning model called the Convolutional Long Short-Term Memory (ConvLSTM). Moreover, we also compare the model with Multi-Layer Perceptron (MLP), and Long Short-Term Memory (LSTM). We use temperature data taken from the ERA-5 period years 2018 to 2020 located in Kemayoran, Jakarta, Indonesia. This research aims to investigate the accuracy of short-term temperature forecasting by using these three models. The model is built to predict short-term temperatures for 1, 3, and 7 days ahead. The performance of the three methods is measured by calculating the Root Mean Square Error (RMSE), Mean Square Error (MAE), and Coefficient Correlation (CC). The result shows that the LSTM performs better than the other methods to forecast 1, 3, and 7 days, i.e., with the lowest RMSE, MAE, and higher CC. 

Fruit Fly in a Challenging Environment: Impact of Short-Term Temperature Stress on the Survival, Development, Reproduction, and Trehalose Metabolism of Bactrocera dorsalis (Diptera: Tephritidae).

Simple SummaryBactrocera dorsalis (Hendel) is a widespread and economically important insect pest, infesting various fruits and vegetables. Due to the instability of climate change in early spring and autumn, extreme cold and hot temperatures were developed in a short period of time. Exposure to sudden short-term high or low temperatures may affect the reproduction, development, and physiological changes of B. dorsalis. In this study, we determined the effects of short-term temperature treatments on the growth, development, fecundity, and trehalose metabolism of B. dorsalis. The results showed that development and reproduction of the flies were negatively affected when temperature was below 10 °C; or more than 31 °C, even causing permanent sterility at extreme temperatures. The changes of glucose, glycogen, trehalose, and trehalose-6-phosphate synthase level had a correlation with the population dynamics of the fruit flies. Our present study can provide a scientific basis for population monitoring, prediction, and comprehensive prevention of the fruit fly.An understanding of physiological damage and population development caused by uncomfortable temperature plays an important role in pest control. In order to clarify the adaptability of different temperatures and physiological response mechanism of B. dorsalis, we focused on the adaptation ability of this pest to environmental stress from physiological and ecological viewpoints. In this study, we explored the relationship between population parameters and glucose, glycogen, trehalose, and trehalose-6-phosphate synthase responses to high and low temperatures. Compared with the control group, temperature stress delayed the development duration of all stages, and the survival rates and longevity decreased gradually as temperature decreased to 0 °C and increased to 36 °C. Furthermore, with low temperature decrease from 10 °C to 0 °C, the average fecundity per female increased at 10 °C but decreased later. Reproduction of the species was negatively affected during high-temperature stresses, reaching the lowest value at 36 °C. In addition to significantly affecting biological characteristics, temperature stress influenced physiological changes of B. dorsalis in cold and heat tolerance. When temperature deviated significantly from the norm, the levels of substances associated with temperature resistance were altered: glucose, trehalose, and TPS levels increased, but glycogen levels decreased. These results suggest that temperature stresses exert a detrimental effect on the populations’ survival, but the metabolism of trehalose and glycogen may enhance the pest’s temperature resistance.

Seawater Reverse Osmosis Performance Decline Caused by Short-Term Elevated Feed Water Temperature.

The shortage of fresh water resources has made the desalination of seawater a widely adopted technology. Seawater reverse osmosis (SWRO) is the most commonly used method for desalination. The SWRO process is energy-intensive, and most of the energy in SWRO is spent on pressurizing the seawater to overcome the osmotic barrier for producing fresh water. The pressure needed depends on the salinity of the seawater, its temperature, and the membrane surface properties. Membrane compaction occurs in SWRO due to hydraulic pressure application for long-term operations and operating temperature fluctuations due to seasonal seawater changes. This study investigates the effects of short-term feed water temperature increase on the SWRO process in a full-scale pilot with pretreatment and a SWRO installation consisting of a pressure vessel which contains seven industrial-scale 8” diameter spiral wound membrane elements. A SWRO feed water temperature of 40 °C, even for a short period of 7 days, caused a permanent performance decline illustrated by a strong specific energy consumption increase of 7.5%. This study highlights the need for membrane manufacturer data that account for the water temperature effect on membrane performance over a broad temperature range. There is a need to develop new membranes that are more tolerant to temperature fluctuations.

Study of the Stability of Sandoz Rituximab Biosimilar Rixathon®/Riximyo® When Subjected for up to 21 Days to Ambient Storage

AimThe purpose of this study was to evaluate the extended physicochemical and biological stability of Sandoz Rixathon®/Riximyo® (SDZ-RTX) after exposure to out-of-fridge (OOF) conditions.Materials and MethodsThe impact of the short-term temperature excursion on stability parameters of SDZ-RTX was simulated by subsequently exposing the three batches of SDZ-RTX (100 and 500 mg) to OOF conditions, (I) 25 ± 2 °C/60 ± 5% relative humidity (RH) and (II) 30 ± 2 °C/65 ± 5% RH, for up to 21 days after more than the claimed 36-month shelf-life storage in long-term conditions (5 ± 3 °C). Analytical methods used included the cation exchange chromatography (CEX), size exclusion chromatography (SEC), and non-reducing capillary electrophoresis-sodium dodecyl sulfate (nrCE-SDS), as well as biological activity by complement-dependent cytotoxicity (CDC)-bioactivity as well as further methods, for example, related to identity and pharmacopoeia test methods.ResultsNo notable changes were observed across all batches with respect to identity (charge and primary structure), pharmaceutical tests (clarity, visible and subvisible particles analytics, container appearance, degree of coloration, pH, osmolality, extractable volume, and container closure integrity testing), protein content by UV and microbiological parameters (sterility and bacterial endotoxins) under both OOF conditions. Only minor changes were observed for parameters evaluated via SEC, CEX, and nrCE-SDS. For potency (CDC-bioactivity) only one of the batches showed a relevant change. Even for these stability-indicating test methods, all analyzed parameters complied with the shelf-life specifications.ConclusionSDZ-RTX is safe for use even under worst-case conditions, for example, after subjecting it for up to 21 days at OOF conditions (25 ± 2 °C/60 ± 5% RH or 30 ± 2 °C/65 ± 5% RH) after the batches had reached an age that was already beyond the claimed shelf-life.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40268-022-00393-4.

Influence of Evotherm on the thermal equilibrium time of unmodified and modified bituminous binders

ABSTRACT The rheological properties of bitumen largely influence the performance of the pavement. Determination of rheological properties of bitumen depends on thermal equilibrium time. The main objective of this study is to evaluate the effect of Evotherm, a chemical warm mix additive on the thermal equilibrium time of bituminous binders. The bituminous binders used for this study included two unmodified binders, a polymer-modified bitumen (PMB) and a crumb rubber-modified bitumen (CRMB). The thermal equilibrium times for bituminous binders with and without Evotherm were measured using a dynamic shear rheometer. The results indicate that the thermal equilibrium time primarily depends on the type of binder, wherein the asphaltene content, presence of polymer and rubber influence thermal equilibrium time. The higher thermal equilibrium times observed for the Evotherm-modified PMB40 binder and Evotherm-modified CRMB60 binder in unaged condition can be attributed to a change in morphology and chemical interaction respectively upon the addition of Evotherm. Lesser thermal equilibrium time exhibited by short-term aged Evotherm binders can be because of the reduced formation of ageing compounds due to reduced short-term ageing temperature and presence of Evotherm. The linear regression model well predicted the thermal equilibrium time based on test temperature and softening point of binders.

A Minimally Invasive Approach for Preventing White Wine Protein Haze by Early Enzymatic Treatment.

Protein stability in bottled white wine is an essential organoleptic property considered by consumers. In this paper, the effectiveness of an early enzymatic treatment was investigated by adding a food-grade microbial protease at two different stages of winemaking: (i) at cold settling, for a short-term and low temperature (10 °C) action prior to alcoholic fermentation (AF); (ii) at yeast inoculum, for a long-lasting and medium temperature (18 °C) action during AF. The results reveal that protease sufficiently preserved its catalytic activity at both operational conditions: 10 °C (during cold settling) and 18 °C (during AF). Furthermore, protease addition (dosage 50–150 μL/L) raised the alcoholic fermentation rate. The treatment at yeast inoculum (dosage 50 μL/L) had a remarkable effect in preventing haze formation, as revealed by its impact on protein instability and haze-active proteins. This minimally invasive, time and resource-saving enzymatic treatment, integrated into the winemaking process, could produce stable white wine without affecting color quality and phenol content.

The Effect of High and Low Ambient Temperature on Infant Health: A Systematic Review.

Children, and particularly infants, have physiological, anatomic, and social factors that increase vulnerability to temperature extremes. We performed a systematic review to explore the association between acute adverse infant outcomes (children 0–1 years) and exposure to high and low ambient temperatures. MEDLINE (Pubmed), Embase, CINAHL Plus, and Global Health were searched alongside the reference lists of key papers. We included published journal papers in English that assessed adverse infant outcomes related to short-term weather-related temperature exposure. Twenty-six studies met our inclusion criteria. Outcomes assessed included: infant mortality (n = 9), sudden infant death syndrome (n = 5), hospital visits or admissions (n = 5), infectious disease outcomes (n = 5), and neonatal conditions such as jaundice (n = 2). Higher temperatures were associated with increased risk of acute infant mortality, hospital admissions, and hand, foot, and mouth disease. Several studies identified low temperature impacts on infant mortality and episodes of respiratory disease. Findings on temperature risks for sudden infant death syndrome were inconsistent. Only five studies were conducted in low- or middle-income countries, and evidence on subpopulations and temperature-sensitive infectious diseases was limited. Public health measures are required to reduce the impacts of heat and cold on infant health.

The rising threat of climate change for arthropods from Earth's cold regions: Taxonomic rather than native status drives species sensitivity.

Polar and alpine regions are changing rapidly with global climate change. Yet, the impacts on biodiversity, especially on the invertebrate ectotherms which are dominant in these areas, remain poorly understood. Short‐term extreme temperature events, which are growing in frequency, are expected to have profound impacts on high‐latitude ectotherms, with native species being less resilient than their alien counterparts. Here, we examined in the laboratory the effects of short periodic exposures to thermal extremes on survival responses of seven native and two non‐native invertebrates from the sub‐Antarctic Islands. We found that survival of dipterans was significantly reduced under warming exposures, on average having median lethal times (LT50) of about 30 days in control conditions, which declined to about 20 days when exposed to daily short‐term maxima of 24°C. Conversely, coleopterans were either not, or were less, affected by the climatic scenarios applied, with predicted LT50 as high as 65 days under the warmest condition (daily exposures at 28°C for 2 h). The native spider Myro kerguelensis was characterized by an intermediate sensitivity when subjected to short‐term daily heat maxima. Our results unexpectedly revealed a taxonomic influence, with physiological sensitivity to heat differing between higher level taxa, but not between native and non‐native species representing the same higher taxon. The survival of a non‐native carabid beetle under the experimentally imposed conditions was very high, but similar to that of native beetles, while native and non‐native flies also exhibited very similar sensitivity to warming. As dipterans are a major element of diversity of sub‐Antarctic, Arctic and other cold ecosystems, such observations suggest that the increased occurrence of extreme, short‐term, thermal events could lead to large‐scale restructuring of key terrestrial ecosystem components both in ecosystems protected from and those exposed to the additional impacts of biological invasions.

Attention based long-term air temperature forecasting network: ALTF Net

Air temperature is one of the most important meteorological parameters related with atmospheric and environmental research. In this context, accurate prediction and forecasting of temperature is crucial due to the current global climate change. Although, the short term temperature forecasting have been more or less conquered in the past by using predictive algorithms, the long-term temperature forecasting is still a challenging task. Long term temperature forecasting is previously attempted by deep learning methods like Recurrent Neural Network (RNN), Long Short Term Memory (LSTM), etc. However, the gradient explosion and gradient vanishing problems of the RNN based networks were the major roadblock in the path of long-term prediction. So, in this paper, an attention-based model called ALTF Net (Attention based Long term Temperature Forecasting Network) approaches this problem using an Encoder–Decoder orientation. The Encoder encodes the relative dependencies of the auto-regressive time-series into an attention tensor which is used by the Decoder to produce the prediction. The Encoder is augmented to incorporate a convolution block to recognize the seasonal patterns. The proposed model ALTF uses a Transformer with an augmented encoder to predict temperature up to 150 days with high accuracy, a feat which would be difficult using RNN and LSTM. The model has been trained with 25+ years of data from 5 cities around the globe and the performance have been rigorously evaluated in terms of RMSE, MAE, R2, and correlation values. It is observed that the proposed model dominated over several baselines (ARIMA, RFR, KNN, MLP, RNN, CNN, LSTM, and Transformer) for long term temperature forecasting.

Variation in Short-term Temperature Fluctuations Across China During the Past 60 Years

Variation in Short-term Temperature Fluctuations Across China During the Past 60 Years

Photosynthetic response and antioxidative activity of ‘Hass’ avocado cultivar treated with short-term low temperature

To investigate the effects of short-term low temperatures, three-year-old avocado (Persea americana cv. Hass) seedlings were treated with 1, − 2, or − 5 °C for 1 h and subsequently recovered in ambient condition for 24 h. Leaf color changes were investigated with chlorophyll, carotenoid, and phenolic contents. Photosynthetic responses were examined using gas exchange analysis. With H2O2 contents as oxidative stresses, enzymatic (ascorbate peroxidase, APX; glutathione reductase, GR; catalase, CAT; peroxidase, POD) and non-enzymatic antioxidant activities were determined using spectrophotometry. Leaves in the avocado seedlings started to be discolored with changes in the contents of chlorophyll a, carotenoids, and phenolics when treated with − 5 °C. However, the H2O2 content was not different in leaves treated with low temperatures. Photosynthetic activities decreased in leaves in the seedlings treated with − 5 °C. Of antioxidant enzymes, APX and GR have high activities in leaves in the seedlings treated with 1 and − 2 °C. In leaves in the seedlings treated with − 5 °C, the activities of all enzymes decreased. Non-enzymatic antioxidant activity was not different among leaves treated with low temperatures. These results indicated that APX and GR would play a critical role in withstanding chilling stress in ‘Hass’ avocado seedlings. However, under lethal temperature, even for a short time, the plants suffered irreversible damage with the breakdown of photosystem and antioxidant system.

Forecasting short-term road surface temperatures considering forecasting horizon and geographical attributes – an ANN-based approach

The ability to forecast road surface temperature (RST) in advance is an important asset for winter maintenance (WRM) operations. It effectively allows for the reduction of WRM cost through more efficient use of their maintenance resources. However, considering extensive road networks that must be monitored and the extent at which RST varies over time, WRM agencies have constantly been looking for better ways to generate accurate road weather forecasts as they strive to optimize their WRM services and maintain safe travels. To tackle this, this study developed RST forecasting models using an Artificial Neural Network (ANN). RST measurements collected by six selected stationary road weather information systems (RWIS) stations in Alberta, Canada were utilized to validate the feasibility and applicability of the proposed method developed herein. The developed models were found to generate highly accurate results with mean absolute error (MAE) values of 0.64, 1.20, 1.59, 2.16, 2.56, and 3.03 °C for 1-h, 2-h, 3-h, 4-h, 5-h, and 6-h ahead forecasts, respectively. The novelty of this study lies in investigating the probable effect of some external factors on model performance, where it was revealed that forecasting horizon and geographical attributes influenced forecasting accuracies. Upon investigating the hypothesis that locational attributes would affect forecasting accuracies, the results confirmed that accuracy improved with increasing latitude, and decreasing elevations – worthwhile findings that can potentially lead to developing more refined models for generating highly accurate location-specific RST forecasts.

The modification of air particulate matter on the relationship between temperature and childhood asthma hospitalization: An exploration based on different interaction strategies

The influence of temperature on childhood asthma was self-evident, yet the issue of whether the relationship will be synergized by air pollution remains unclear. The study aimed to investigate whether the relationship between short-term temperature exposure and childhood asthma hospitalization was modified by particulate matter (PM). Data on childhood asthma hospitalization, meteorological factors, and air pollutants during 2013–2016 in Hefei, China, were collected. First, a basic Poisson regression model combined with a distributed lag nonlinear model was used to assess the temperature-childhood asthma hospitalization relationship. Then, two interactive strategies were applied to explore the modification effect of PM on the temperature-childhood asthma hospitalization association. We found a greater effect of cold (5th percentile of temperature) on asthma during days with higher PM2.5 (RR: 2.16, 95% CI: 1.38, 3.38) or PM10 (RR: 1.87, 95% CI:1.20, 2.91) than that during days with lower PM2.5 (RR: 1.64, 95% CI: 1.06, 2.54) or PM10 (RR: 1.52, 95% CI: 0.98, 2.36). In addition, we observed a greater modification effect of PM2.5 on the cold-asthma association than did PM10, with a per 10 μg/m3 increase in PM2.5 and PM10 associated with increases of 0.065 and 0.025 for the RR corresponding to the 5th temperature percentile, respectively. For the temperature-related AF, moderate cold showed the largest change magnitude with the PM levels rising compared with other temperature ranges. For the subgroup, Females and those aged 6–18 years were more sensitive to the modification effect of PM2.5 or PM10 on the cold-asthma association. Our findings demonstrated that particulate matter could modify the associations between temperature and childhood asthma hospitalization.

Short-term effects of ambient temperature on the risk of preeclampsia in Nanjing, China: a time-series analysis

ObjectivesPrevious studies on the association between temperature and preeclampsia mainly considered temperature on a monthly or seasonal time scale. The objective of this study was to assess the preeclampsia risk associated with short-term temperature exposure using daily data.Study designDaily preeclampsia hospitalization data, daily meteorological data and daily air pollutant data from Nanjing were collected from 2016 to 2017. Both the T test and distributed lag nonlinear model (DLNM) were applied to assess the short-term effect of temperature on preeclampsia risk. Three kinds of daily temperature, including the daily mean temperature, daily minimum temperature and daily maximum temperature, were analysed.ResultsWhen the daily number of preeclampsia hospital admissions was divided into two subgroups based on temperature, it was significantly larger on cold days than on hot days. Regarding the mean temperature, a very low level of mean temperature (4.5 °C, lag = 0–20) and a low level of mean temperature (9.1 °C, lag = 0–20) increased the cumulative relative risk of preeclampsia by more than 60%. At the same time, a very high level of mean temperature (28.7 °C, lags = 0–10, 0–15, 0–20) and a high level of mean temperature (24.1 °C, lags = 0–10, 0–15) decreased the cumulative relative risk of preeclampsia by more than 35%. At a minimum temperature, a very low level of minimum temperature (0.9 °C, lag 0–5) and a low level of minimum temperature (5.6 °C, lag 0–5) increased the cumulative relative risk of preeclampsia by more than 55%. At the same time, a high level of mean temperature (20.9 °C, lags = 0, 0–5) decreased the cumulative relative risk of preeclampsia by more than 20%. The maximum temperature result was similar to the mean temperature result.ConclusionsBoth direct and lag effects of low temperature on preeclampsia were demonstrated to be significant risk factors. These results could be used to help pregnant women and the government reduce preeclampsia risk.

Multigenerational Effects of Short-Term High Temperature on the Development and Reproduction of the Zeugodacus cucurbitae (Coquillett, 1899)

Zeugodacus cucurbitae is an important pest of fruit and vegetable crops in tropical and subtropical regions, and high-temperature stress can have different effects on the development and reproduction of successive generations of Z. cucurbitae. To clarify the multigenerational effects of short-time high temperature on the development and reproduction of Z. cucurbitae, the newly emerged adults of the contemporary (F1 generation) and the next generation (F2 generation) were exposed to short-term high temperatures of 25 °C, 33 °C, 37 °C, 41 °C, and 45 °C for 1 h, and the multigenerational (F1, F2, and F3 generation) effects of these temperatures on the development and reproduction of Z. cucurbitae were evaluated. The results showed that (1) when the F1 was exposed to short-term high temperature, the egg production and lifespan of the F1 decreased continuously with the increasing temperature, except for the 45 °C treatment for 1 h, which stimulated egg production. Only the 41 °C group had significantly higher egg production and lifespan than the control group in the F3. (2) In the F1 and F2 that were exposed to short-term high temperature, the F1 and F3 were consistent with the results of F1 that were exposed to short-term high temperature. In conclusion, the effects of high-temperature intensity and frequency on multiple generations of Z. cucurbitae were different. The results of this study can elucidate the effects of short-term high-temperature stress on the growth, development, and reproduction of Z. cucurbitae in different generations, and provide a reference basis for the integrated control of Z. cucurbitae.

The effect of short-term temperature exposure on vital physiological processes of mixoplankton and protozooplankton

Sudden environmental changes like marine heatwaves will become more intense and frequent in the future. Understanding the physiological responses of mixoplankton and protozooplankton, key members of marine food webs, to temperature is crucial. Here, we studied two dinoflagellates (one protozoo- and one mixoplanktonic), two ciliates (one protozoo- and one mixoplanktonic), and two cryptophytes. We report the acute (24 h) responses on growth and grazing to a range of temperatures (5–34 °C). We also determined respiration and photosynthetic rates for the four grazers within 6 °C of warming. The thermal performance curves showed that, in general, ciliates have higher optimal temperatures than dinoflagellates and that protozooplankton is better adapted to warming than mixoplankton. Our results confirmed that warmer temperatures decrease the cellular volumes of all species. Q10 coefficients suggest that grazing is the rate that increases the most in response to temperature in protozooplankton. Yet, in mixoplankton, grazing decreased in warmer temperatures, whereas photosynthesis increased. Therefore, we suggest that the Metabolic Theory of Ecology should reassess mixoplankton's position for the correct parameterisation of future climate change models. Future studies should also address the multigenerational response to temperature changes, to confirm whether mixoplankton become more phototrophic than phagotrophic in a warming scenario after adaptation.

Evolutionary trade-offs between heat and cold tolerance limit responses to fluctuating climates.

The evolutionary potential of species to cope with short-term temperature fluctuations during reproduction is critical to predicting responses to future climate change. Despite this, vertebrate research has focused on reproduction under high or low temperatures in relatively stable temperate climates. Here, we characterize the genetic basis of reproductive thermal tolerance to temperature fluctuations in the ostrich, which lives in variable environments in tropical and subtropical Africa. Both heat and cold tolerance were under selection and heritable, indicating the potential for evolutionary responses to mean temperature change. However, we found evidence for a negative, genetic correlation between heat and cold tolerance that should limit the potential for adaptation to fluctuating temperatures. Genetic constraints between heat and cold tolerance appear a crucial, yet underappreciated, factor influencing responses to climate change.

Acute effects of ambient temperature on lung function of a panel of school children living in Dhaka, Bangladesh

IntroductionShort-term exposure to ambient temperature plays a significant role in human health. However, studies examining ambient temperature and lung function are scarce in locations with a tropical environment. To address this research gap, the current study investigated the effects of short-term ambient temperature on lung function in children and seasonal variation in this association in Dhaka, Bangladesh. MethodsThe study was conducted in three schools located in three cities inside and around Dhaka. Repeated lung function measurements were obtained from a panel of 315 school children (including 86 asthmatic children) aged 9–16 years in 2013. Linear mixed-effects models adjusted for potential confounders were used to examine the effect of ambient temperature on lung function. ResultsShort-term exposure to low ambient temperature was associated with a significant decrement in children's lung function. For each 1 °C decrease in daily mean temperature at cumulative lag of the current and previous day, lung function parameter values were −3.02% (95% CI, −1.69 to −4.35) for peak expiratory flow (PEF), and −1.48% (95% CI, −0.75 to −2.22) for forced expiratory volume within 1 s (FEV1). A significant seasonal variation was also observed in these associations, as the estimated adverse effects of decrease in daily mean temperature on lung function measures were primarily evident in winter. DiscussionThis study suggests that short-term ambient exposure to decrease in temperature adversely affect lung function. A significant seasonal modification in the association between temperature and lung function was also observed for these children living in an environment with a tropical climatic condition as the adverse effect of decrease in ambient temperature was primarily observed in winter than in summer.