Effect Of Environmental Temperature Research Articles

Behavior and surface properties of microalgae indicate environmental changes

We conducted a microcosm experiment under near-natural conditions to investigate the effects of environmental stressors temperature and salinity on the response of three microalgal species. The response of microalgae to increased temperature and altered salinity is species-specific, with cell barrier complexity playing an important protective role. At decreasing salinity, the green flagellate cells of Dunaliella tertiolecta vibrate around the point and become stiff while their physiological activity is at its highest, which may indicate that organic matter is being released into the medium. At the highest salinity, Tetraselmis suecica showed the highest growth rate along with the hydrophobic behavior of the cells, which is a favorable condition for the formation of aggregates. Under these conditions, the cells could enter the cyst stage, while the content of polar lipids could mediate cell adhesion to the natural interfaces. Cylindrotheca closterium, a diatom with an organosilicate cell wall, also showed the highest physiological activity at decreasing salinity. However, the cells were softest and exhibited hydrophilic behavior, implying that released organic material could alter the surface properties of the diatom. This study provides insight into the behavioral, mechanical, and molecular changes of microalgae under near-natural conditions, which may contribute to a fundamental understanding of how biochemistry and mechanics interact to control the functional behavior of microalgal cells in climatically altered aquatic systems.

Climate-dependent effectiveness of nonpharmaceutical interventions on COVID-19 mitigation

Environmental factors have a significant impact on the transmission of infectious diseases. Existing results show that the novel coronavirus can persist outside the host. We propose a susceptible–exposed–presymptomatic–infectious–asymptomatic–recovered–susceptible (SEPIARS) model with a vaccination compartment and indirect incidence to explore the effect of environmental conditions, temperature and humidity, on the transmission of the SARS-CoV-2 virus. Using climate data and daily confirmed cases data in two Canadian cities with different atmospheric conditions, we evaluate the mortality rates of the SARS-CoV-2 virus and further estimate the transmission rates by the inverse method, respectively. The numerical results show that high temperature or humidity can be helpful in mitigating the spread of COVID-19 during the warm summer months. Our findings verify that nonpharmaceutical interventions are less effective if the virus can persist for a long time on surfaces. Based on climate data, we can forecast the transmission rate and the infection cases up to four weeks in the future by a generalized boosting machine learning model.

Resiliency of fast-growing and slow-growing genotypes of broiler chickens submitted to different environmental temperatures: growth performance and meat quality

Growth performance and meat quality were assessed in 238 chicks of both sexes belonging to a commercial crossbreed (Ross 308), and 2 Italian local breeds (Bionda Piemontese-BP and Robusta Maculata-RM). The chickens were kept in 2 rooms at standard environmental conditions or under heat stress (+4.7°C on average) until slaughtering (42 d of age for Ross 308 and 99 d for RM and BP chickens). The Ross chickens showed the highest final live weight, feed intake, and daily weight gain, and the best feed conversion ratio compared to the local breeds (P < 0.001), with RM performing better than BP chickens. Thus, Ross chickens had the heaviest carcasses, the highest slaughter, and breast yields followed by RM and BP chickens (P < 0.001). At the pectoralis major (p. major) muscle, Ross chickens showed the highest pH, lightness, and yellowness, besides the highest cooking losses, whereas BP showed the highest redness (P < 0.001). Ross meat had higher water and ether extract contents, and lower crude protein content compared to BP and RM (P < 0.001), whereas no differences among genotypes were measured for the fatty acid profile. At the sensory analysis, Ross breasts had a higher juiciness compared to BP ones, besides a lower score for "brothy and chickeny/meaty" and a higher one for "wet feathers" compared to local breeds (0.05 < P < 0.001). The increase of the room temperature decreased growth performance and cold carcass weight (P < 0.001) compared to standard conditions, whereas the rate of α-linolenic acid in the meat increased (P < 0.01). The effect of a high environmental temperature on growth performance and slaughter and meat quality traits was more pronounced in Ross compared to BP and RM chickens (0.05 < P <0.001; significant interaction genotype×temperature). In conclusions, local chicken breeds showed lower performance and slaughter yield compared to the commercial genotype, but more favorable meat quality traits and higher resilience to the environmental heat-stress.

Investigation of temperature and flux effects on heavy ion induced degradation in SiC Schottky diode

In this work, the effects of environmental temperature and ion flux on heavy-ion irradiation damage in commercial SiC Schottky diodes were experimentally characterized. The result shows that the room temperature (25 °C) irradiation is the worst setting than high temperatures. In particular, the reverse leakage current IR increment at the highest temperature (150 °C) is about one-fifth of that at room temperature. The damage is more serious under high flux irradiation, and the IR increment introduced by higher flux (∼10,000 ions/(cm2∙s)) is four times larger than that by lower flux (∼300 ions/(cm2∙s)). After room temperature annealing for more than one year, the DUTs still show the same damage characteristics, which indicates the degradation damage induced by heavy ions is permanent. The variation of power dissipation induced by the synergistic effect of heavy ion incident and the electric field is the root mechanism. The results would help estimate the feasibility of the usage of SiC power devices in space.

Temperature effects on metabolism and energy requirement during the fast growth phase in the red-footed tortoise, Chelonoidis carbonaria.

Early life is a challenging phase because of the high rates of morphophysiological development and growth. Changes in ambient temperature, which directly affect energy metabolism and digestive functions in ectotherms, may be of great impact during this phase. We addressed this issue in red-footed tortoise (Chelonoidis carbonaria) hatchlings kept in captivity. To this end, we investigated the effect of temperature (28°C and 18°C) on mass-specific gross energy intake (GEIm), daily body mass gain (MG), daily intake of gross energy (GEI), digestible energy (DEI), resting metabolic rate (RMR), and specific dynamic action (SDA) components during different seasons in the first 13months after hatching. Greater GEIm and MG were observed in spring (381.7 ± 84.9J.g-0.86.day-1 and 0.9 ± 0.4g.day-1) and summer (356.9 ± 58.9J.g-0.86.day-1 and 1.0 ± 0.4g.day-1). The highest and lowest RMRs at 28°C were observed in spring (36.4 ± 5.1kJ.kg-1.day-1) and winter (22.4 ± 6.2kJ.kg-1.day-1), respectively. Regardless season, hatchlings showed greater GEI and DEI, O2 consumption, CO2 production, RMR, maximum metabolic rate after feeding (FMRMAX), and heat increment (FMRMAX- RMR) at 28°C compared to 18°C. In addition, the significant body mass influence showed allometric exponents of 0.62 at 28°C and 0.92 at 18°C for RMR. Our results indicate an important effect of environmental temperature on energy requirements and utilization in C. carbonaria hatchlings, which is seasonally influenced even in this early phase of life.

Numerical Study on the Effects of Environmental Temperature of Major Cities in California on the Capacity Fade of Battery Cells in Electric Vehicles

Numerical Study on the Effects of Environmental Temperature of Major Cities in California on the Capacity Fade of Battery Cells in Electric Vehicles

Microstructural characteristics evolution of asphalt mastics under cyclic environmental temperature variations

Environmental temperature-effect is the primary factor responsible for asphalt pavement failure. Asphalt pavement exposed to the atmosphere is constantly subjected to the thermal cycles induced by environmental temperature fluctuations, and the resulting thermal cracks significantly reduce the durability of asphalt pavement. Nevertheless, the influence of cyclic temperature variations on the performance degradation of asphalt binder materials is often overlooked. To address this, accelerated thermal cycling test was conducted on two asphalt mastics to simulate repeated environmental temperature variations. Dynamic shear rheological test (DSR) and atomic force microscopy test (AFM) were performed to characterize the evolution of the macroscopic rheological properties and microstructural characteristics under five cyclic temperature ranges. Pearson correlation analysis was utilized to explore the correlation between macro and micro properties. Following thermal cycling, it was observed that the two asphalt mastics experienced a decline in their viscous properties and became more elastic, resulting in a decrease in their stress relaxation capacity and asphalt-aggregate interaction on a macroscopic level. The microstructure transitioned from a multiphase to a homogeneous structure, while the expansion of the valley structure indicated the accumulation of microscopic defects. The larger the temperature variations and the higher the cyclic temperatures are, the more severe the deterioration in the viscoelasticity and microstructures of asphalt mastics is; the degradation of the micromechanical characteristics directly affects the macroscopic rheological properties. The bee structure ratio, the adhesion, and relaxation properties are sensitive to cyclic temperature variations and recommended to characterize the thermal cycling resistance. In comparison to 90# asphalt mastic, the SBS modified asphalt mastic exhibits great resistance to thermal deterioration. This study deepens the understanding of the causes of asphalt pavement performance deterioration in regions with frequent environmental temperature fluctuations.

Experimental study of ice melting of concrete permeable brick sidewalks using embedded carbon fibre heating wire

Electric heating methods have been proven to be effective means to melt ice on sidewalks and bridge decks. However, sidewalks are covered with permeable concrete bricks separated by gaps, which differ from surfaces of roads and bridge decks. Therefore, it is necessary to study methods of melting ice on sidewalks. In this paper, a method for melting ice on sidewalks based on carbon fibre heating wire (CFHW) is proposed. The experiments compare the effects of various environment temperatures, wind speeds, and energising voltages and spacings of CFHW on the surface temperature and melting of ice on sidewalk specimens. The transfer law of heat energy produced by CFHW inside the specimen and the effect of sealing concrete brick holes with a thermal conductive silicone grease in ice melting sidewalks are analysed. The results show that the proposed method has good ice melting performance on sidewalks.

Environmental Temperature Effect on Hydraulic Behavior and Stability of Shallow Slopes

This study established a study framework to quantify the safety factors of unsaturated shallow slopes at different temperatures. This study is based on a non-isothermal soil water characteristic curve model quantifying the temperature-dependent hydraulic properties of soils. The hydraulic coupling analysis models HYDRUS 2D and The Slope Cube Module were used for finite element modeling. A slope stability analysis was performed based on the local factor of safety (LFS) theory. An increased temperature decreased the soil matric suction, suction stress, effective stress, and LFS, weakening the soil strength. Slope modeling analysis showed that soils were dominated by different water retention mechanisms before and after rainfall infiltration, and the trends caused by temperature changes also changed accordingly. This study provides insights into the relationship between soil mechanical properties and temperature, which is valuable for maintaining soil stability and preventing geological hazards.

A Cross-Diagnosis Method for Determining the Structural Condition of a Long-Span Suspension Bridge Based on the Spatial Windows of Distributed Strain Data

Using structural health monitoring (SHM) techniques, Brillouin optical time-domain analysis (BOTDA) sensors can be mounted along the main box girder entire length of a long-span suspension bridge, and the high-density measured points strain monitoring data can be obtained. However, insufficient research has been conducted on accurately diagnosing the structural condition of a long-span suspension bridge by using the abovementioned strain monitoring data. To address this issue, a cross-diagnosis method that determines the structural condition of long-span suspension bridges based on the distributed strain data spatial window is proposed in this study. First, the distributed strain data spatial window based on a long-span suspension bridge structural symmetry is defined. Then, a method that divides the distributed strain data of the bridge main box girder into different spatial windows using mutual information between the strain data from BOTDA sensors is presented. The special symmetry of the environmental temperature effect on the spatial window structural performance is carried out to separate the temperature effect from the strain monitoring data; this process can effectively reduce the interference of ambient temperature on the results of the structural condition diagnosis. Second, using a convolutional neural network, a diagnosis index of the structural condition is generated by using the correlation model between the high-density measured points and the distributed strain data belonging to one whole spatial window. Regarding one spatial window, the proposed diagnosis index can effectively reflect the variation in the distributed strain correlation model caused by the damaged condition of the long-span suspension bridge to achieve cross-diagnosis of the structural condition of the bridge. Finally, the effectiveness of the proposed method is demonstrated through a numerical simulation using strain monitoring data obtained from a real bridge.

Performance analysis of two typical greenhouse lettuce production systems: commercial hydroponic production and traditional soil cultivation.

Due to the shortage of land and water resource, optimization of systems for production in commercial greenhouses is essential for sustainable vegetable supply. The performance of lettuce productivity and the economic benefit in greenhouses using a soil-based system (SBS) and a hydroponic production system (HPS) were compared in this study. Experiments were conducted in two identical greenhouses over two growth cycles (G1 and G2). Three treatments of irrigation volumes (S1, S2, and S3) were evaluated for SBS while three treatments of nutrient solution concentration (H1, H2, and H3) were evaluated for HPS; the optimal levels from each system were then compared. HPS was more sensitive to the effects of environmental temperature than SBS because of higher soil buffer capacity. Compared with SBS, higher yield (more than 134%) and higher water productivity (more than 50%) were observed in HPS. We detected significant increases in ascorbic acid by 28.31% and 16.67% and in soluble sugar by 57.84% and 32.23% during G1 and G2, respectively, compared with SBS. However, nitrate accumulated in HPS-grown lettuce. When the nutrient solution was replaced with fresh water 3 days before harvest, the excess nitrate content of harvested lettuce in HPS was removed. The initial investment and total operating cost in HPS were 21.76 times and 47.09% higher than those in SBS, respectively. Consideration of agronomic, quality, and economic indicators showed an overall optimal performance of the H2 treatment. These findings indicated that, in spite of its higher initial investment and requirement of advanced technology and management, HPS was more profitable than SBS for commercial lettuce production.

Solar-assisted temperature vacuum swing adsorption for direct air capture: Effect of relative humidity

Direct air capture (DAC) has emerged as a promising tool to address the sizeable non-point sources of CO2 emissions. However, energy penalty of its regeneration process is extremely high due to the low CO2 concentration in the atmosphere. This paper aims to explore the potential of a temperature vacuum swing adsorption (TVSA) system for DAC which utilizes solar energy and condensation heat recovered from air conditioners. The effect of indoor environmental parameters especially for relative humidity (RH) is targeted for carbon removal processes. It demonstrates that 40% RH is the optimal value with regard to the minimum heat consumption of 12.16 MJ/kg. Then four representative cases with different energy supply methods for the regeneration processes, i.e., solar-assisted condensation heat recovery, solar energy, condensation heat, and electricity, are compared and analyzed in terms of techno-economic aspects to seek the best system configuration. The effects of various indoor environmental conditions, e.g., temperature, RH, and CO2 concentration are also counted. The results demonstrate that the levelized cost of DAC (LCOD) and the cost calculated via net present value (NPV) increase with the increased temperatures and the reduced CO2 partial pressure. Due to a tradeoff between the increased adsorption capacity and regeneration heat in the presence of water, a minimum value of economic performance could be obtained at 30% RH. It reveals a novel and cost-effective TVSA combined system for DAC, which may bring more merits to approach carbon mitigation shortly.

Effect of Fiber Misalignment and Environmental Temperature on the Compressive Behavior of Fiber Composites.

This experimental study investigated how defects, in particular fiber misalignment, affect the mechanical behavior of glass fiber composites (GFRP) under compressive loading. GFRP cross-plies with three different types of fiber misalignment, namely a fold, a wave, and an in-plane undulation, were fabricated using the resin transfer molding process. The compressive tests were performed at four different temperatures, in order to investigate the role of a change in the matrix properties on the strength of the composite. The experiments showed that the defects, especially at lower temperatures, had a significant impact on the mechanical properties of the composite, exceeding the proportion of the defects inside the composite. With increasing temperature, the damage mechanism changed from fiber-dominated to matrix-dominated and, in doing so, decreased the significance of fiber misalignment for the mechanical behavior.

Investigation on the Influence of Production and Incubation Temperature on the Growth, Virulence, Germination, and Conidial Size of Metarhizium brunneum for Granule Development.

Important for the infection of an insect with an entomopathogenic fungus and its use as a plant protection agent are its growth, conidiation, germination, and virulence, which all depend on the environmental temperature. We investigated not only the effect of environmental temperature but also that of production temperature of the fungus. For this purpose, Metarhizium brunneum JKI-BI-1450 was produced and incubated at different temperatures, and the factors mentioned as well as conidial size were determined. The temperature at which the fungus was produced affects its subsequent growth and conidiation on granule formulation, the speed of germination, and the conidial width, but not its final germination or virulence. The growth and conidiation was at its highest when the fungus was produced at 25 °C, whereas when the germination was faster, the warmer the fungus was produced. The incubation temperature optimum of JKI-BI-1450 in relation to growth, speed of germination, and survival time was 25-30 °C and for conidiation 20-25 °C. Conidial length decreased with increasing incubation temperature. Although the fungus could not be adapted to unfavorable conditions by the production temperature, it was found that the quality of a biological control agent based on entomopathogenic fungi can be positively influenced by its production temperature.

Thermoneutrality and severe malaria: investigating the effect of warmer environmental temperatures on the inflammatory response and disease progression.

Most studies using murine disease models are conducted at housing temperatures (20 - 22°C) that are sub-optimal (ST) for mice, eliciting changes in metabolism and response to disease. Experiments performed at a thermoneutral temperature (TT; 28 - 31°C) have revealed an altered immune response to pathogens and experimental treatments in murine disease model that have implications for their translation to clinical research. How such conditions affect the inflammatory response to infection with Plasmodium berghei ANKA (PbA) and disease progression is unknown. We hypothesized that changes in environmental temperature modulate immune cells and modify host response to malaria disease. To test this hypothesis, we conducted experiments to determine: (1) the inflammatory response to malarial agents injection in a peritonitis model and (2) disease progression in PbA-infected mice at TT compared to ST. In one study, acclimatized mice were injected intraperitoneally with native hemozoin (nHZ) or Leishmania at TT (28 - 31°C) or ST, and immune cells, cytokine, and extracellular vesicle (EV) profiles were determined from the peritoneal cavity (PEC) fluid. In another study, PbA-infected mice were monitored until end-point (i.e. experimental malaria score ≥4). We found that Leishmania injection resulted in decreased cell recruitment and higher phagocytosis of nHZ in mice housed at TT. We found 398 upregulated and 293 downregulated proinflammatory genes in mice injected with nHZ, at both temperatures. We report the presence of host-derived EVs never reported before in a murine parasitic murine model at both temperatures. We observed metabolic changes in mice housed at TT, but these did not result to noticeable changes in disease progression compared to ST. To our knowledge, these experiments are the first to investigate the effect of thermoneutrality on a malaria murine model. We found important metabolic difference in mice housed at TT. Our results offer insights on how thermoneutrality might impact a severe malaria murine model and directions for more targeted investigations.

The relationship between temperature, growth rate and body condition of Bufo bufo toadlets prior to their first hibernation

Abstract The effect of environmental temperature on the growth and body condition of common toad (Bufo bufo) toadlets was studied during their first terrestrial growth season, following metamorphosis, at a pond in south Dorset, UK, between 2010 and 2021. Toadlet samples were collected annually on the first day of emergence and then approximately once a week until late September/early October. In total, 15-19 samples were collected annually depending on the duration of the toadlet activity season. Toadlet snout-vent length (mm) and body mass (mg) of each captured toadlet was measured and their body condition (Scaled Mass Index: SMI) estimated both annually and for each annual quarter season. Toadlet growth rate and SMI varied between years and were significantly correlated with the duration of their first growth season and its lowest recorded temperature. Growth rate declined as the duration of the growth season increased whilst the reverse was true for SMI. Growth rates also increased as temperatures increased and vice versa for SMI. SMI was inversely correlated to growth rate and suggest that toadlets may enter their first hibernation larger, but in poorer condition, following warm summers than cool summers, and that this may have the potential to reduce their survivorship during a following mild winter. Assuming that similar relationships, between growth rates, body condition and environmental temperatures are not restricted to toadlets during their first terrestrial growth season, then this scenario may also be applicable to subsequent juvenile stages, further increasing the potential consequences for individual survival and fitness.

Activity modulation and selection for forests help giant anteaters to cope with temperature changes

Mammals use thermoregulatory behavioural strategies to reduce the cost of physiological thermoregulation. Environmental temperatures should, therefore, impact their decisions. We investigated the effect of environmental temperature on the movement decisions of a large mammal with low capacity for physiological thermoregulation: the giant anteater, Myrmecophaga tridactyla. We GPS-tracked 14 giant anteaters in the Brazilian Pantanal wetland over 5 years. We used hidden Markov models to identify two behavioural states (encamping, as a proxy of resting, and moving, as a proxy of being active) across individuals' trajectories. Then, we estimated the effect of environmental temperature on the probability of moving across the hours of the day in open and forested habitats. We also used integrated step selection analysis to understand how environmental temperature drives giant anteater's habitat selection across the day. Giant anteaters showed three important behavioural thermoregulatory strategies in response to environmental temperature changes: they modulated activity duration, completely shifted activity period on a scale of days and selected forests as thermal shelters. With increasing environmental temperature, giant anteaters increased activity duration, nocturnality and diurnal selection for forests, increasing energy intake while avoiding heat gain by solar radiation. With decreasing environmental temperature, they decreased activity duration, increased diurnality and increased nocturnal selection for forests, thus gaining heat from solar radiation when active and taking shelter in milder microclimates when resting. Besides their high short-term behavioural plasticity regarding activity, giant anteaters also used forests to thermoregulate. These results provide insights into how other mammals could respond to climate change. In particular, we highlight the importance of forests as thermal shelters, offering milder temperatures than adjacent open areas during both hot and cold weather spells. Thermal shelters will become more and more indispensable to animal thermoregulation as the frequency and intensity of extreme weather events increase.

Effects of environmental temperature on the thermal runaway of lithium-ion batteries during charging process

Lithium-ion batteries with relatively narrow operating temperature range have provoked concerns regarding the safety of LIBs. In this work, a series of experiments were conducted to explore the thermal runaway (TR) behaviors of charging batteries in a high/low temperature test chamber. The effects of charging rates (0.5 C, 1 C, 2 C, and 3 C), and ambient temperature (2 °C, 32 °C and 56 °C) are comprehensively investigated.The results indicate that the cell exhibited greater thermal hazard at the high charging rate and ambient temperature conditions. As the charging rate increased from 0.5 C to 3 C, more lithium intercalated in the anode prompt the TR triggered in advance, the TR onset temperature decreased from 297.5 °C to 264.7 °C. In addition, the charging time decreased with the elevated ambient temperature, resulting in a relatively higher TR onset temperature and lower maximum temperature, and the average TR critical time declined by 115–143 s. Finally, the TR required less heat accumulation with increasing of charging rate and ambient temperature, and the heat generation of side reaction played a substantial role that accounted for approximately 54%∼63%. These results provide an insight into the charging cell thermal runaway behaviors in complex operation environments and deliver valuable guidance for improving the safety of cell operation.

Influence of environmental temperature on the hand-feel perception of textiles

The present study investigated the effect of environmental temperature on the hand-feel perception of textiles. Participants were exposed to three different climate conditions (10 °C/20 °C/30 °C, RH 65 %) to simulate cool, mild, and warm environments. Hand-feel attributes, comfort, and preferences of a wide range of textiles were rated by the participants. Participants’ body responses to the different temperatures were controlled by monitoring participants’ aural temperature, mean skin temperature, hand temperature, tactile sensitivity, and environmental perception. Fabric weight was measured to monitor changes in textile properties induced by the different environmental conditions. The outcomes of the study suggest that the environmental temperature led to significant changes in participants’ aural temperature, mean skin temperature, hand temperature, tactile sensitivity, and environmental perception, affecting the hand-feel perception of the different textiles. Thus, the present study provides insight for practitioners to develop more comfortable textiles for specific environmental temperatures by establishing a basis for understanding how environmental temperature, body responses, and hand feel perception interact.

Wear and damage behaviours of wheel and rail materials: Effects of friction modifier and environmental temperature

Low temperature conditions can aggravate the wear and fatigue damage of the wheel and the rail materials. Friction modifier (FM) is used to control the adhesion and alleviate the wear and damage. However, the wear and damage behaviours of wheel and rail with the application of FM under low temperature have not been revealed. Therefore, the present study aims to investigate the effect of FM on the wear and the rolling contact fatigue (RCF) damage of the wheel and the rail under low temperature conditions. Tests were conducted on a rolling-sliding wear testing apparatus with the samples enclosed in a temperature-controlled chamber. The results indicated that the effect of FM on the wear and the RCF damage of the wheel and the rail was influenced by the temperature significantly. Compared with the dry condition, the wear rate of the wheel decreased obviously at all temperature conditions when using FM. Meanwhile, the RCF damage of the wheel was relatively slight. Besides, there was no significant difference among the RCF damage of the wheel at different temperatures both under the dry and the FM conditions. At room temperature, the application of FM could alleviate the RCF damage of the rail. Under the low temperature condition, the performance of FM would fail, which would result in a severe oil wedge effect on the rail specimen. Therefore, the application of FM could induce a higher wear rate and severe RCF damages on rail material at the low temperature condition. The results of the present study could provide guidance for the development and design of FMs used in cold regions.