scholarly journals Evaluation of the effect of high air temperature on the behavioural activity and physical performance of animals (in a rat model)

2021 ◽  
Vol 100 (8) ◽  
pp. 782-786
Author(s):  
Vladimir E. Kriyt ◽  
Yuliya N. Sladkova ◽  
Maksim V. Sannikov ◽  
Aleksandr O. Pyatibrat
Keyword(s):  
Physical Performance ◽  
Air Temperature ◽  
White Male ◽  
Heat Exposure ◽  
Physical Endurance ◽  
Physical Factors ◽  
Long Term Effects ◽  
Research Activity ◽  
Fire Hazards ◽  
Behavioural Activity

Introduction. The profession of firefighters belongs to extreme activities. Fire hazards include flames, sparks, heat flow, elevated ambient temperatures, increased concentrations of toxic combustion and thermal decomposition products, decreased oxygen concentrations, and reduced visibility in smoke. High air temperature during fire extinguishing is one of the main adverse physical factors affecting firefighters’ bodies. Material and methods. The study was carried out on 124 outbred white male 3-month rats weighing 250-300 g, divided randomly into two groups: the first group (62 rats) underwent single hyperthermia. The second group (62 rats) experienced daily hyperthermia for 14 days. The study of the behavioural activity of animals was carried out after single and prolonged hyperthermia using the following methods: “Open field”, “Elevated cruciform maze”, Porsolt’s test, running on a treadmill. The tests were performed two times: the first time - before exposure, the second - after, with intervals between tests of at least two weeks. Results. The data obtained indicate that the high ambient temperature causes changes in the behavioural responses in animals, which is expressed by an increase in the level of anxiety, a decrease in motor and research activity, the development of depressive states, and a decrease in physical endurance. Conclusion. An experimental model of extreme heat exposure on animals showed the emergence and persistence of changes in animals’ behavioural activity and physical performance indicators. This experiment can be used to study the long-term effects of high temperatures on firefighters’ bodies.

Stimulants: From Coca to Caffeine

2020 ◽  
Author(s):  
Jerrold Winter
Keyword(s):  
South America ◽  
Physical Performance ◽  
Personal Experience ◽  
16Th Century ◽  
Physical Endurance ◽  
The Sun ◽  
Ruling Class ◽  
Italian Physician ◽  
Native Workers ◽  
The World

Unlike the opiates, which are a rather homogeneous group, the drugs we call stimulants come in a variety of forms. In this chapter, we will devote most of our time to the classical stimulants, cocaine and the amphetamines, but will consider as well caffeine, nicotine, ephedrine, and modafinil. All are capable of enhancing mental and physical performance, and some produce distinctly pleasurable effects that sometimes lead to addiction. About the time that humans living in what is now South America started to draw on the walls of their caves, one among them discovered the unusual properties of the coca shrub. When the leaves were chewed, wondrous things happened to the chewer: Hunger and fatigue were replaced by feelings of strength and power; the world seemed not such a bad place to live. By the time Francisco Pizarro led his conquistadors into Peru early in the 16th century, coca leaf had found an exalted place in the Incan Empire. One legend has it that coca was brought from heaven to earth by Manco Capac, son of the Sun god and the Inca from whom the ruling class traced its lineage. (Interesting how often royalty has claimed divine origins.) The Spaniards developed no great respect for coca, regarding it as but another facet of a pagan people who had no claim on civilization. But the new rulers were nothing if not practical. Coca allowed native workers to be pushed beyond the normal bounds of physical endurance. More tin and silver could be brought from the mines with fewer workers fed less food. Coca leaf lost its status as a sacrament and a pleasure of the ruling class. It became a part of the internal economy of Spanish Peru, a means of enhancing productivity, and a contributor to the destruction of the Incan people and their civilization. It was inevitable that Europeans would become familiar with the effects of coca leaf both by their observation of native use and by personal experience. In 1859, an Italian physician named Paolo Mantegazza who had spent some time among the Peruvian natives put it this way.

scholarly journals Improving the organism's resistance to the stress “time deficiency” by iodine-containing thyroid hormones

2019 ◽  
Keyword(s):  
Gastric Mucosa ◽  
Thyroid Hormones ◽  
Adrenal Glands ◽  
White Male ◽  
Relative Weight ◽  
Statistical Processing ◽  
Male Rats ◽  
Stress System ◽  
Physical Endurance ◽  
Resistance To Stress

The high prevalence of diseases of stressful etiology and insufficient knowledge of the mechanisms of their pathogenesis, as well as factors limiting the intensity of the stress reaction, among which iodine-containing thyroid hormones have recently been studied, determine the relevance of the study. The purpose of the work is to study the effect of thyroid status on the organism's resistance to emotional stress. The experiment was performed on 180 white male rats weighing 220–240 g. Stress was modeled according to the “time deficiency” method, when the animal, trying to avoid contact with water quickly filling the spiral tunnel, was forced to move up. Statistical processing of the obtained results was carried out using generally accepted medical statistics methods using program “Statistica 10.0”. The introduction of mercazolyl (25 mg / kg for 20 days), which determines a lower concentration of iodine-containing thyroid hormones in the blood under stress, prevents an increase in the relative weight of the adrenal glands and the corticosteroids level in the blood, an increase in physical endurance and horizontal motor activity of animals, inhibits their research behavior, and aggravates damage gastric mucosa in these conditions. The introduction of L-thyroxine in small doses (1.5-3 μg / kg 28 days) provides a higher level of iodine-containing thyroid hormones and increases the body's resistance to stress (limits the changes in the relative weight of the adrenal glands, spleen and thymus, corticosteroids and insulin levels in the blood , behavior and physical endurance of animals, damage to the gastric mucosa). Iodine-containing thyroid hormones increase the body's resistance to stress of the “time deficiency”, which proves their important role in the body's anti-stress system.

scholarly journals Monthly Variation of Physico-Chemical Parameters of Haleji lake, Sindh, Pakistan

2019 ◽  
Vol 10 (1) ◽  
pp. 36-41
Author(s):  
Shahina Rao ◽  
Muhammad Arshad Azmi
Keyword(s):  
Dissolved Oxygen ◽  
Water Temperature ◽  
Air Temperature ◽  
Physical Factors ◽  
Monthly Variation ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Light Green

Present work is based on the physico-chemical parameters of Haleji lake. Physical factors and chemistry oflake water were analyzed with regular intervals. The color of water showed variation from light green to yellowishgreen, air temperature ranged between 20 °C to 35 °C, water temperature between 17 °C to 33 °C , pH 5.5 to 7.5,dissolved oxygen 2.04 mg/L to 6.44 mg/L, salinity 0.32 mg/L to 1.1 mg/L, alkalinity from 30 mg/L to 100 mg/L,acidity 10 to 96 mg/L, sulphate 4.5 mg/L to 305 mg/L, phosphate from 1 mg/L to 190 mg/L, and nitrates 9 mg/L to 270mg/L during 2006, 2007 and 2008 respectively.

scholarly journals Effects of ashwagandha root extract on physical performance – a clinical review

2021 ◽  
Vol 11 (12) ◽  
pp. 337-343
Author(s):  
Karol Mazur ◽  
Marcin Lewicki ◽  
Dominika Mazur ◽  
Mateusz Tyniec ◽  
Agata Smoleń
Keyword(s):  
Physical Performance ◽  
Human Life ◽  
Physical Endurance ◽  
Root Extract ◽  
Strength Increase ◽  
Natural Substances ◽  
Obesity And Diabetes ◽  
Conducting Research ◽  
Reducing Stress ◽  
Mental And Physical Health

Sport is an important aspect of human life, affecting mental and physical health. Physical activity is one of the most effective ways of preventing the diseases of civilisation, such as coronary heart disease, hypertension, obesity and diabetes. There are many substances and methods that are used by athletes to improve physical performance, increase muscle mass and strength, increase concentration or suppress excessive emotions or reduce body weight to improve sports results. However, there is a need for research to find natural substances of plant origin, the use of which will lead to an increase in physical performance and will be fully legal and without side effects. Some scientists are conducting research into the use of ashwagandha root extract to improve physical performance. The aim of this study was to assess the efficacy and safety of ashwagandha root extract in the treatment of insomnia, anxiety and in reducing stress. Our study material consisted of publications, which were found in PubMed, ResearchGate and Google Scholar databases. In order to find the proper publications, the search has been conducted with the use of a combination of key words like: ''ashawagandha'', ''physical performance'', ''physical endurance'', ''muscle strength". The first step was to find proper publications from the last 15 years. The second step was to carry out an overview of the found publications.

A mobile sensor-based Approach for Analyzing and Mitigating Urban Heat Hazards

2020 ◽  
Author(s):  
Yanzhe Yin ◽  
Andrew Grundstein ◽  
Deepak Mishra ◽  
Navid Hashemi ◽  
Lakshmish Lakshmish
Keyword(s):  
Machine Learning ◽  
Air Temperature ◽  
Heat Exposure ◽  
Ambient Air ◽  
Temperature Data ◽  
Mobile Sensors ◽  
Mobile Sensor ◽  
High Quality ◽  
Urban Heat ◽  
Heat Hazard

<p>High-quality temperature data at a finer spatial-temporal scale is critical for analyzing the risk of heat hazards in urban environments. The variability of urban landscapes makes cities a challenging landscape for quantifying heat exposure. Most of the existing heat hazard studies have inherent limitations on two fronts: the spatial-temporal granularities are too coarse and the ability to track the actual ambient air temperature instead of land surface temperature. Overcoming these limitations requires radically different research approaches, both the paradigms for collecting the temperature data and developing models for high-resolution heat mapping. We present a comprehensive approach for studying urban heat hazards by harnessing a high-quality hyperlocal temperature dataset from a network of mobile sensors and using it to refine the satellite-based temperature products. We mounted vehicle-borne mobile sensors on thirty city buses to collect high-frequency (5 sec) temperature data from June 2018 to Nov 2019. The vehicle-borne data clearly show significant temperature differences across the city, with the largest differences of up to 10℃ and morning-afternoon diurnal changes at a magnitude around 20℃. Then we developed a machine learning approach to derive a hyperlocal ambient air temperature (AAT) product by combining the mobile-sensor temperature data, satellite LST data, and other influential biophysical parameters to map the variability of heat hazard over areas not covered by the buses. The machine learning model output highlighted the high spatio-temporal granularity in AAT within an urban heat island. The seasonal AAT maps derived from the model show a well-defined hyperlocal variability of heat hazards which are not evident from other research approaches. The findings from this study will be beneficial for understanding the heat exposure vulnerabilities for individual communities. It may also create a pathway for policymakers to devise targeted hazard mitigation efforts such as increasing green space and developing better heat-safety policies for workers.</p>

scholarly journals Severing Red Alder: Timing the Cut to Achieve the Best Mortality

2003 ◽  
Vol 18 (3) ◽  
pp. 199-201
Author(s):  
Douglas Belz
Keyword(s):  
Air Temperature ◽  
Physical Factors ◽  
Window Of Opportunity ◽  
Red Alder ◽  
Carbohydrate Reserve ◽  
Effective Time ◽  
Calendar Date

Abstract The best time to cut red alder varies. Mortality shifts across regional zones. The most effective time to cut is not determined by calendar date, but instead depends on environmental, biological, and physical factors that affect initial budbreak and potential mortality. Several trials and continuing observations lead the author to believe air temperature and seasonal moisture, along with carbohydrate reserve, are the more potent influences. These influences affect the time to begin cutting, how long cutting can continue, when cutting should stop, and the degree of mortality. Monitoring budbreak date and moisture patterns can be used to determine a favorable window of opportunity that will produce 50% or higher mortality on the cut red alder. The cutting window can be used across wide geoclimatic zones with good success. West. J. Appl. For. 18(3):199–201.

scholarly journals Worldwide reef surveys highlight different adaptive responses to heat between coral taxa

2021 ◽  
Author(s):  
Oliver Selmoni ◽  
Gael Lecellier ◽  
Veronique Berteaux-Lecellier ◽  
Stephane Joost
Keyword(s):  
Heat Stress ◽  
Heat Waves ◽  
Coral Cover ◽  
Heat Exposure ◽  
Negative Association ◽  
Conservation Strategies ◽  
Long Term Effects ◽  
Thermal Anomalies ◽  
Adaptive Processes

Coral reefs around the world are under threat due to widespread decline of hard corals caused by anomalous heat waves. Coral taxa of different morphologies are known to have different sensitivities to heat stress. However, little is known about how long-term effects of heat exposure differ between coral taxa, nor in particular how such effects might drive adaptive processes. Here, we combined worldwide reef survey data with remotely sensed thermal anomalies to evaluate how local rates of taxa-specific coral cover were associated with heat stress. We found a negative association between coral cover and heat stress, where associations were weaker for corals with boulder-like morphology (massive corals), intermediate for corals with arborescent morphology (branching corals) and stronger for corals with encrusting or laminar morphology (plating corals). Additionally, we found that the negative association between branching coral cover and recent exposure to heat stress (measured as the year before a survey) was mitigated by the effect of long-term heat stress (measured since 1985), suggesting that adaptive processes occurred. In contrast, this "mitigating effect" of past heat-stress was not observed for either massive or plating corals. We hypothesize that these different responses to recent and past heat stress mirror different life history traits of coral taxa. For instance, branching corals are known to show higher sensitivities to heat stress and faster growth rates, two characteristics that might boost adaptive rates via evolutionary processes, when compared with other taxa. The results of this work suggest that all coral taxa, regardless of their morphology, will be "losers" of coral bleaching, and that conservation strategies should be adjusted to match taxa-specific responses to heat stress.

scholarly journals Monthly Variation of Physico-Chemical Parameters of Haleji lake, Sindh, Pakistan

2019 ◽  
Vol 10 (1) ◽  
pp. 36-41
Author(s):  
Shahina Rao ◽  
Muhammad Arshad Azmi
Keyword(s):  
Dissolved Oxygen ◽  
Water Temperature ◽  
Air Temperature ◽  
Physical Factors ◽  
Monthly Variation ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Light Green

Present work is based on the physico-chemical parameters of Haleji lake. Physical factors and chemistry oflake water were analyzed with regular intervals. The color of water showed variation from light green to yellowishgreen, air temperature ranged between 20 °C to 35 °C, water temperature between 17 °C to 33 °C , pH 5.5 to 7.5,dissolved oxygen 2.04 mg/L to 6.44 mg/L, salinity 0.32 mg/L to 1.1 mg/L, alkalinity from 30 mg/L to 100 mg/L,acidity 10 to 96 mg/L, sulphate 4.5 mg/L to 305 mg/L, phosphate from 1 mg/L to 190 mg/L, and nitrates 9 mg/L to 270mg/L during 2006, 2007 and 2008 respectively.

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