scholarly journals A 3-D virtual human thermoregulatory model to predict whole-body and organ-specific heat-stress responses

2021 ◽  
Author(s):  
Ginu Unnikrishnan ◽  
Rajeev Hatwar ◽  
Samantha Hornby ◽  
Srinivas Laxminarayan ◽  
Tushar Gulati ◽  
...  
Keyword(s):  
Heat Stress ◽  
Stress Responses ◽  
Environmental Conditions ◽  
The Body ◽  
Activity Level ◽  
Stress Conditions ◽  
Whole Body ◽  
Triceps Brachii ◽  
Thermoregulatory Model ◽  
The Impact

Abstract Objective This study aimed at assessing the risks associated with human exposure to heat-stress conditions by predicting organ- and tissue-level heat-stress responses under different exertional activities, environmental conditions, and clothing. Methods In this study, we developed an anatomically detailed three-dimensional thermoregulatory finite element model of a 50th percentile U.S. male, to predict the spatiotemporal temperature distribution throughout the body. The model accounts for the major heat transfer and thermoregulatory mechanisms, and circadian-rhythm effects. We validated our model by comparing its temperature predictions of various organs (brain, liver, stomach, bladder, and esophagus), and muscles (vastus medialis and triceps brachii) under normal resting conditions (errors between 0.0 and 0.5 °C), and of rectum under different heat-stress conditions (errors between 0.1 and 0.3 °C), with experimental measurements from multiple studies. Results Our simulations showed that the rise in the rectal temperature was primarily driven by the activity level (~ 94%) and, to a much lesser extent, environmental conditions or clothing considered in our study. The peak temperature in the heart, liver, and kidney were consistently higher than in the rectum (by ~ 0.6 °C), and the entire heart and liver recorded higher temperatures than in the rectum, indicating that these organs may be more susceptible to heat injury. Conclusion Our model can help assess the impact of exertional and environmental heat stressors at the organ level and, in the future, evaluate the efficacy of different whole-body or localized cooling strategies in preserving organ integrity.

Heat Sensing and Lipid Reprograming as a Signaling Switch for Heat Stress Responses in Wheat

2020 ◽  
Vol 61 (8) ◽  
pp. 1399-1407 ◽  
Author(s):  
Mostafa Abdelrahman ◽  
Takayoshi Ishii ◽  
Magdi El-Sayed ◽  
Lam-Son Phan Tran
Keyword(s):  
Heat Stress ◽  
Plant Species ◽  
Stress Responses ◽  
Calcium Influx ◽  
Global Climate ◽  
Wheat Yield ◽  
High Temperature Stress ◽  
Membrane Lipid ◽  
Wheat Varieties ◽  
The Impact

Abstract Temperature is an essential physical factor that affects the plant life cycle. Almost all plant species have evolved a robust signal transduction system that enables them to sense changes in the surrounding temperature, relay this message and accordingly adjust their metabolism and cellular functions to avoid heat stress-related damage. Wheat (Triticum aestivum), being a cool-season crop, is very sensitive to heat stress. Any increase in the ambient temperature, especially at the reproductive and grain-filling stages, can cause a drastic loss in wheat yield. Heat stress causes lipid peroxidation due to oxidative stress, resulting in the damage of thylakoid membranes and the disruption of their function, which ultimately decreases photosynthesis and crop yield. The cell membrane/plasma membrane plays prominent roles as an interface system that perceives and translates the changes in environmental signals into intracellular responses. Thus, membrane lipid composition is a critical factor in heat stress tolerance or susceptibility in wheat. In this review, we elucidate the possible involvement of calcium influx as an early heat stress-responsive mechanism in wheat plants. In addition, the physiological implications underlying the changes in lipid metabolism under high-temperature stress in wheat and other plant species will be discussed. In-depth knowledge about wheat lipid reprograming can help develop heat-tolerant wheat varieties and provide approaches to solve the impact of global climate change.

scholarly journals 262 Heat stress alleviation and dynamic temperature measurement for growing beef cattle

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 192-193
Author(s):  
Sheyenne M Augenstein ◽  
Meredith A Harrison ◽  
Sarah C Klopatek ◽  
James W Oltjen
Keyword(s):  
Heat Stress ◽  
Body Temperature ◽  
Beef Cattle ◽  
Ambient Temperature ◽  
The Body ◽  
Control Group ◽  
Temperature Threshold ◽  
Sprinkler Systems ◽  
Significant Difference ◽  
The Impact

Abstract Heat stress continues to be a challenge for feedlot producers, forcing physiological adaptations in beef cattle that can have a negative impact on gain and carcass quality. Feedlots may want to incorporate systems that aid in mitigating heat stress, including sprinkler systems, which are commonly found on dairies. The objective of this study was to determine the impact of sprinkler systems on the body temperature of growing feedlot steers applied at three different temperature thresholds. Thirty-two Angus-cross beef steers (298 ± 15 SD days of age) were randomly assigned to 8 pens. Treatments were assigned to pens according to location to avoid drainage issues, with one replicate located on the eastern side of the feedlot and the other replicate located on the western side. Treatments including no sprinklers (C), high temperature threshold sprinklers (HT), moderate temperature threshold sprinklers (MT) or low temperature threshold sprinklers (LT). Sprinklers (flow rate: 5.11 L/min) were activated at 33°C (HT), 28°C (MT), and 23°C (LT) for five minutes at corresponding temperatures every thirty minutes for 57 days. Rectal temperature of steers in their pens was measured in the morning (0800 h), afternoon (1500 h), and evening (1900 h) three days each week (Monday, Wednesday, Friday) for a total of 19 experimental days. Weather measurements, including ambient temperature, windspeed, humidity and solar radiation were recorded at each measurement time along with the maximum values for each day. The change in body temperature (ΔBT) between the morning and afternoon was affected by ambient temperature (P < 0.01); MT (P = 0.02) and LT (P = 0.02) – different than C. There was no significant difference between sprinkler treatments and the control group (P > 0.05). Day affected (ΔBT) between the morning and afternoon (P < 0.05) and the afternoon and evening (P < 0.05). When averaged by day, the control group was significantly higher than MT (P = 0.04) between the morning and afternoon. The control group was also significantly higher than LT between the morning and afternoon (P = 0.03) and the afternoon and evening (P < 0.01). The change in steer body temperature between afternoon and morning was affected by ambient temperature, and averaged across days, lowering the temperature threshold for sprinkling decreased in the afternoon and evening body temperature increase in steers.

Behaviour of Pigeon Excreta on Masonry Surfaces

2018 ◽  
Vol 23 (1) ◽  
pp. 15-28 ◽  
Author(s):  
Dirk HR Spennemann ◽  
Melissa Pike ◽  
Maggie J Watson
Keyword(s):  
Relative Humidity ◽  
Environmental Conditions ◽  
Building Material ◽  
Urban Areas ◽  
Real Life ◽  
The Body ◽  
Individual Bird ◽  
Bird Droppings ◽  
Pigeon Droppings ◽  
The Impact

Abstract Pigeon droppings are implicated in spoiling and decay of buildings. Several studies have examined the effects and chemistry of accumulations of pigeon droppings under highly localised pigeon roosts. Scant information exists on the impact caused by individual pigeon droppings at perch sites, even though these constitute the majority of bird use in urban areas. This study experimentally examined the processes that affect masonry immediately after pigeon excreta have been voided from the body and what effects discrete, fresh pigeon droppings have on different kinds of sandstone. The experiments demonstrated the susceptibility of freshly deposited excreta to environmental conditions (relative humidity and precipitation). In real-life situations, with pigeon excreta deposited on window ledges, cornices and parapets, the majority of damage would occur within the first two weeks of deposition. After that, the majority of individual droppings would have either dissolved or desiccated to such a degree that they would have rolled off. Much of the observed staining is superficial. While individual bird droppings make a building look dirty, even for months at a time, the effect on the building material is not substantial unless other factors come into play such as colonisation of the excreta by mould or leaching of salts from the excreta.

Just Skin and Bones: The Longing for Wholeness of the Body in the Book of Job

2008 ◽  
Vol 58 (3) ◽  
pp. 287-299 ◽  
Author(s):  
Alec Basson
Keyword(s):  
Social Relations ◽  
The Body ◽  
Whole Body ◽  
Book Of Job ◽  
Personal Loss ◽  
Ancient Israel ◽  
Social Unity ◽  
Ideal Body Image ◽  
Ideal Body ◽  
The Impact

AbstractThe book of Job recounts the story of an individual who grapples with the enigma of suffering. In addition to his personal loss, the supplicant's body also comes under attack. Furthermore, the physical distress experienced by Job is exacerbated by the attitude of his kinsmen. His disintegrated body has lead to severed social relations. Given the fact that the body mediates the plaintiff's involvement in society and represented social unity in ancient Israel, Job longs for a whole body as the ideal body image. The ancient Israelites only regarded the whole body as pure, real and acceptable. This contribution argues that to appreciate fully the allusions to bodily degeneration in the book of Job, the importance of wholeness of the physical body in ancient Israel and the impact it had on the socio-religious structure should be taken into account.

scholarly journals Stress-responsive HILPDA is necessary for thermoregulation during fasting

2017 ◽  
Vol 235 (1) ◽  
pp. 27-38 ◽  
Author(s):  
Matthew J VandeKopple ◽  
Jinghai Wu ◽  
Lisa A Baer ◽  
Naresh C Bal ◽  
Santosh K Maurya ◽  
...  
Keyword(s):  
Lipid Droplet ◽  
Stress Responses ◽  
Genetically Engineered ◽  
Whole Body ◽  
Brown Adipocyte ◽  
Ambulatory Activity ◽  
Genetically Engineered Mouse Model ◽  
Knockout Animals ◽  
The Impact

Hypoxia-inducible lipid droplet-associated protein (HILPDA) has been shown to localize to lipid droplets in nutrient-responsive cell types such as hepatocytes and adipocytes. However, its role in the control of whole-body homeostasis is not known. We sought to measure cell-intrinsic and systemic stress responses in a mouse strain harboring whole-body Hilpda deficiency. We generated a genetically engineered mouse model of whole-body HILPDA deficiency by replacing the coding Hilpda exon with luciferase. We subjected the knockout animals to environmental stresses and measured whole-animal metabolic and behavioral parameters. Brown adipocyte precursors were isolated and differentiated in vitro to quantify the impact of HILPDA ablation in lipid storage and mobilization in these cells. HILPDA-knockout animals are viable and fertile, but show reduced ambulatory activity and oxygen consumption at regular housing conditions. Acclimatization at thermoneutral conditions abolished the phenotypic differences observed at 22°C. When fasted, HILPDA KO mice are unable to maintain body temperature and become hypothermic at 22°C, without apparent abnormalities in blood chemistry parameters or tissue triglyceride content. HILPDA expression was upregulated during adipocyte differentiation and activation in vitro; however, it was not required for lipid droplet formation in brown adipocytes. We conclude that HILPDA is necessary for efficient fuel utilization suggesting a homeostatic role for Hilpda in sub-optimal environments.

scholarly journals Impact of Engaging the Nonthrowing Arm on Maximal Ball Velocity From an Overhand Throw With Both the Dominant and Nondominant Arms: A Pilot Study

2021 ◽  
pp. 1-18
Author(s):  
Alanna Weisberg ◽  
Hyun Suk Lee ◽  
Tak Fung ◽  
Larry Katz
Keyword(s):  
The Body ◽  
Whole Body ◽  
Camera Motion ◽  
Ball Speed ◽  
Kinematic Data ◽  
Overhand Throw ◽  
Ball Velocity ◽  
Analysis System ◽  
The Impact ◽  
Camera Motion Analysis

The overhand throw is a complex whole-body motor skill that is fundamental to many sports and activities. When throwing properly, the momentum generated to complete the movement begins in the lower body and transfers through the trunk to the throwing arm. This proof-of-concept study’s primary purpose was to evaluate the impact of the nonthrowing arm on the ball speed during an overhand throw with both the dominant and nondominant arms. Eighteen participants (age: 20.20 ± 2.90 years, nine women) were divided into two intervention groups: a pulling group taught to engage the nonthrowing arm through a pull toward the body and a nonpulling group taught the overhand throw using a component-based physical education curriculum. Each participant completed 12 total throws, six for each side (dominant and nondominant arm). Ball speed and kinematic data were collected using an eight-camera motion analysis system and were assessed using a pre–post study design. The two groups showed significant improvements pre–post when throwing with both the dominant and nondominant arms. Based on effect size comparisons, engaging the nonthrowing arm makes a meaningful difference in maximal ball velocity.

scholarly journals Impacts of heat stress conditions on mortality from respiratory and cardiovascular diseases in Brazil

2020 ◽  
Vol 11 (3) ◽  
pp. 297-330
Author(s):  
Beatriz Fátima Alves de Oliveira ◽  
Ludmilla da Silva Viana Jacobson ◽  
Letícia Palazzi Perez ◽  
Ismael Henrique da Silveira ◽  
Washington Leite Junger ◽  
...  
Keyword(s):  
Heat Stress ◽  
Respiratory Diseases ◽  
Stress Conditions ◽  
Response Curves ◽  
Capital Cities ◽  
Wet Bulb Globe Temperature ◽  
Risk Of Exposure ◽  
Potential Impact ◽  
Globe Temperature ◽  
The Impact

This study assesses the risk of exposure to heat stress conditions and their potential impact on mortality from cardiovascular and respiratory diseases in Brazilian capital cities for warming levels of 1.5 °C, 2.0 °C and 4.0 °C in the RCP8.5 scenario. The risk of exposure and the impact of heat stress conditions on mortality were measured by the Wet Bulb Globe Temperature (WBGT) index. The impact on health was estimated by applying exposure-response curves between WBGT and health outcomes in the projections. The potential impact on mortality was measured by attributable fraction of mortality due to heat stress. The results showed an increase in heat stress conditions for Brazil, especially in the Northern and Center-Western regions. The estimated curves showed an association between the WBGT and mortality by cardiovascular and respiratory diseases in Brazil, with an upward impact trend, according to the levels of warming and heterogeneous results among the capitals.  

scholarly journals Influens of mole rats burrow activity to restore the soils proteolytic activity in terms of their man-made pollution

2016 ◽  
Vol 17 (3-4) ◽  
pp. 107-111
Author(s):  
T. A. Zamesova
Keyword(s):  
Heavy Metals ◽  
Metal Concentration ◽  
Proteolytic Activity ◽  
The Body ◽  
Activity Level ◽  
Forming Process ◽  
Vital Functions ◽  
The Impact ◽  
Burrow Activity

Heavy metals, especially their large concentration, is toxic for all living creatures because they are accumulating in the living things tissues. Theirs excessive levels evoke coagulation of proteins that cause immediate death of cells. Heavy metals get into the ground by different ways: directly because of using, precipitation, industrial pollution. Their impacts may be either time limited and have low toxicity or, alternatively, it may be long-termed and expressing the pollutants' ability to accumulate them in the body and supply chains. In the edaphotop block of land biogeocenosis most of the transformation processes begin with soil degradation ones. This leads to disruption of soil-forming process cycle of matter and biological productivity of systems. Optimization of a particular system or a block is possible only by acting on their biological relations, which is responsible for managing the system. Distortion or optimization of relations occurs with the animals environmental-forming, the component of which is animals burrow activity. As a result of it, water and chemicals are being reallocated in soil depths, thermal and aeration modes are changed, formed typical zoogenous micro relief with specific physical and chemical properties of the soil. This improves the living conditions of soil micro-organisms. Last ones are involved in soil enzyme activity forming. Enzymes involved in important biochemical processes: synthesis and humus decomposition, hydrolysis of organic compounds, the schedule remains of plants and microorganisms and converted them available to fixation, fix loose items, are actively involved in the cycling of essential elements for plants, in oxidation renewable reactions, etc. It is possible to determine the extent of microorganism’s activity by means of indexes of soil proteolytic activity. Conducted studies of the impact for animals burrow activity on the soils proteolytic activity for artificial forest under conditions of heavy metal pollution. Control plots were contaminated by lead with concentrations of 32; 160; 320 mg/kg of soil, which correspond to the maximum permissible concentration of 1; 5; 10 MAC. Samples were taken at 1st, 3rd and 15th months after contamination; proteolytic activity was determined by the Mishustin application method. Current proteolytic activity of soil is determined in vivo. It is the result of microorganism’s vital functions. And in turn can be an indicator of microbial activity. Contamination of lead depressing vital functions for soil microorganisms. This effect is more noticeable in the first month after contamination. The characteristic dependence of the soil proteolytic activity on metal concentration was observed also, the higher the MPC, the lower proteolytic activity level. The characteristics' dependence of soil proteolytic activity on metal concentration were also observed: the higher MPC, the lower the activity level. It was shown that on the mole rats burrows-dug with lead contaminated the medium proteolytic activity level exceeded control 1.9; 1.76 and 1.53 times respectively, at 1st; 3rd and 15th months after contamination. Based on this we can say that burrowing activity of animals inhibits inhibitory effect of heavy metals and plays an important role in the self-cleaning environment.

scholarly journals Over time Decay of Cortisol Metabolites in Faecal Pellets of Koalas in Central Queensland

Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3376
Author(s):  
Flavia Santamaria ◽  
Rolf Schlagloth ◽  
Rupert Palme ◽  
Joerg Henning
Keyword(s):  
Stress Responses ◽  
Environmental Conditions ◽  
Water Loss ◽  
Physiological Stress ◽  
Animal Health ◽  
Faecal Pellets ◽  
Field Samples ◽  
The Impact ◽  
Over Time ◽  
Cortisol Metabolites

Faecal material can be a valuable source of information for a range of animal health aspects and can be used to measure faecal cortisol metabolites (FCMs). FCM values can relate to physiological stress responses. However, freshly defecated pellets are not always available and environmental conditions, such as temperature and humidity, might affect faecal pellet consistency and FCM levels. Therefore, the impact of environmental conditions on FCMs needs to be evaluated. We collected 107 pellets from two female and two male koalas, exposed them to three types of treatments, and analysed FCMs in these samples with three enzyme immunoassays (EIAs). After analysis, the original FCM values were mathematically corrected for water loss. Results show that the FCMs were more stable when measured using tetrahydrocorticosterone (50c) and 5α-pregnane-3β,11β,21-triol-20-one (37e) EIAs, and were less stable when measured with the cortisol EIA. With 50c, the FCM values did not vary significantly over time either before or after the adjustment with water in the environment treatment group. For samples kept under constant low (25 °C) and high (35 °C) temperatures, the 50c FCM values did not vary significantly over time, after adjustments were made for water loss. Thus, this study highlights the importance of considering the suitability of faecal field samples for FCM analysis. Because water loss was the main driver of FCM changes, we strongly recommend collecting koala pellets that are freshly defecated, despite the effort and time it might take to collect such pellets.

scholarly journals Antioxidant nutrition in Atlantic salmon (Salmo salar) parr and post-smolt, fed diets with high inclusion of plant ingredients and graded levels of micronutrients and selected amino acids

2016 ◽  
Author(s):  
Kristin Hamre ◽  
Nini H. Sissener ◽  
Erik-Jan Lock ◽  
Pål A Olsvik ◽  
Marit Espe ◽  
...  
Keyword(s):  
Amino Acids ◽  
Vitamin C ◽  
Atlantic Salmon ◽  
Stress Responses ◽  
The Body ◽  
Whole Body ◽  
Redox Potentials ◽  
Deficiency Symptoms ◽  
High Consumption ◽  
Dietary Concentration

The shift from marine to plant based ingredients in fish feeds affects the dietary concentrations and bioavailability of micronutrients, amino acids and lipids and consequently warrants a re-evaluation of dietary nutrient recommendations. In the present study, an Atlantic salmon diet high in plant ingredients was supplemented with graded levels of nutrient premix (NP), containing selected amino acids, taurine, cholesterol, vitamins and minerals. This article presents the results on the antioxidant nutrients vitamin C, E and selenium (Se), and effects on tissue redox status. The feed ingredients appeared to contain sufficient levels of vitamin E and Se to cover the requirements to prevent clinical deficiency symptoms. The body levels of α-tocopherol (TOH) in parr and that of Se in parr and post-smolt showed a linear relationship with dietary concentration, while α-TOH in post-smolt seemed to be saturable with a breakpoint near 140 mg kg-1. Ascorbic acid (Asc) concentration in the basal feed was below the expected minimum requirement, but the experimental period was probably too short for the fish to develop visible deficiency symptoms. Asc was saturable in both parr and post-smolt whole body at dietary concentrations of 190 and 63-89 mg kg-1, respectively. Maximum whole body Asc concentration was approximately 40 mg kg-1 in parr and 14 mg kg-1 in post-smolt. Retention ranged from 41 to 10% in parr and from -206 to 12% in post-smolt with increasing NP supplementation. This indicates that the post-smolts had an extraordinarily high consumption of Asc. Analyses of glutathione (GSH) and glutathione disulphide (GSSG) concentrations and the calculated GSH based redox potentials in liver and muscle tissue, indicated only minor effects of diets on redox regulation. However, the post-smolt were more oxidized than the parr. This was supported by the high consumption of Asc and high expression of gpx1 and gpx3 in liver. Based on the present trials, the recommendations for supplementation of vitamin C and E in diets for Atlantic salmon are similar to current practices, e.g 150-200 mg kg-1 of α-TOH and 190 mg kg-1 Asc which was the saturating concentration in parr. Higher concentrations than what would prevent clinical deficiency symptoms are necessary to protect fish against incidents of oxidative stress and to improve immune and stress responses. There were no indications that the Se requirement exceeded the current recommendation of 0.3 mg kg-1.

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