scholarly journals Psychological, Physical, and Heat Stress Indicators Prior to and after a 15-Minute Structural Firefighting Task

Biology ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 104
Author(s):  
Elisa F. D. Canetti ◽  
Scott Gayton ◽  
Ben Schram ◽  
Rodney Pope ◽  
Robin M. Orr
Keyword(s):  
Heat Stress ◽  
Logical Reasoning ◽  
Protective Equipment ◽  
Stress Indicators ◽  
Reasoning Test ◽  
Impaired Cognition ◽  
Highly Correlated ◽  
Logic Reasoning ◽  
Speed And Accuracy ◽  
Cardiovascular Strain

Firefighters work in strenuous conditions for prolonged periods wearing up to 20 kg of personal protective equipment. This often contributes to significant heat and cardiovascular strain. This study examined the relationships between psychological and physical measures taken prior to undertaking a 15 min firefighting task, and the occurrence of heat stress and high levels of fatigue following the task. Nine qualified firefighters completed a 15 min “live burn” scenario designed to mimic a fire started by a two-seater couch in a lounge room and completed simulated tasks throughout the duration. Logical reasoning, speed and accuracy, general motivation and fatigue, and physical and mental effort were recorded pre-scenario, and at 0- and 20-min post-scenario. General motivation and fatigue scores at 0- and 20-min post-scenario were highly correlated with each other (rs = 0.90; p = 0.001). The general motivation and fatigue scores, at 0- and 20-min post-scenario, were also strongly related to pre-task logic/reasoning test scores (Post 0 rs = −0.77, p = 0.016; Post 20 rs = −0.87, p = 0.002). Firefighters with lower logical reasoning and speed and accuracy scores were more susceptible to fatigue and impaired cognition when exposed to rises in core temperature and heat stress.

Increased Air Velocity Reduces Thermal and Cardiovascular Strain in Young and Older Males during Humid Exertional Heat Stress

2015 ◽  
Vol 12 (9) ◽  
pp. 625-634 ◽  
Author(s):  
Heather E. Wright Beatty ◽  
Stephen G. Hardcastle ◽  
Pierre Boulay ◽  
Andreas D. Flouris ◽  
Glen P. Kenny
Keyword(s):  
Heat Stress ◽  
Air Velocity ◽  
Exertional Heat Stress ◽  
Cardiovascular Strain ◽  
Older Males

scholarly journals Effect of Heat Stress on Inter-relationship of Physiological and Biochemical Traits with Grain Yield in Wheat (Triticum aestivum L.)

2020 ◽  
pp. 19-29
Author(s):  
Amrita Kumari ◽  
R. D. Ranjan ◽  
Chandan Roy ◽  
Awadesh Kumar Pal ◽  
S. Kumar
Keyword(s):  
Heat Stress ◽  
Grain Yield ◽  
Flag Leaf ◽  
Grain Filling ◽  
Triticum Aestivum L ◽  
Seedling Stage ◽  
Biochemical Traits ◽  
Highly Correlated ◽  
Complex Phenomena ◽  
Physiological And Biochemical

Heat stress, particularly the stress appears at the time of flowering to grain filling stages causing severe yield loss in wheat. Heat tolerance is complex phenomena that include adjustment in morphological, physiological and biochemical traits of the crop. Present investigation was carried out to understand the effect of terminal heat stress on different traits of wheat. The experiment was conducted in three dates of sowing as timely sown, late sown and very late sown to expose the crop to heat stress at later stages of the crop growth. Significant genetic variations for all the traits evaluated under three conditions indicated the presence of variability for the traits. Trait association analysis revealed that flag leaf chlorophyll content and MSI at seedling stage; MDA at reproductive stage had direct relationship with grain yield. While under very late sown condition MDA and RWC at seedling stages were found to be highly correlated with grain yield. It indicates that MDA, RWC at seedling stage and days to booting, days to milking plays important role in very late sown condition that can be used as selection criteria in breeding programme.

scholarly journals Performances of Limited Area Models for the WORKLIMATE Heat–Health Warning System to Protect Worker’s Health and Productivity in Italy

2021 ◽  
Vol 18 (18) ◽  
pp. 9940
Author(s):  
Daniele Grifoni ◽  
Alessandro Messeri ◽  
Alfonso Crisci ◽  
Michela Bonafede ◽  
Francesco Pasi ◽  
...  
Keyword(s):  
Heat Stress ◽  
Warning System ◽  
Outdoor Environment ◽  
Limited Area ◽  
Warning Systems ◽  
Stress Indicators ◽  
Climate Conditions ◽  
Health Warning ◽  
Globe Temperature ◽  
Meteorological Models

Outdoor workers are particularly exposed to climate conditions, and in particular, the increase of environmental temperature directly affects their health and productivity. For these reasons, in recent years, heat-health warning systems have been developed for workers generally using heat stress indicators obtained by the combination of meteorological parameters to describe the thermal stress induced by the outdoor environment on the human body. There are several studies on the verification of the parameters predicted by meteorological models, but very few relating to the validation of heat stress indicators. This study aims to verify the performance of two limited area models, with different spatial resolution, potentially applicable in the occupational heat health warning system developed within the WORKLIMATE project for the Italian territory. A comparison between the Wet Bulb Globe Temperature predicted by the models and that obtained by data from 28 weather stations was carried out over about three summer seasons in different daily time slots, using the most common skill of performance. The two meteorological models were overall comparable for much of the Italian explored territory, while major limits have emerged in areas with complex topography. This study demonstrated the applicability of limited area models in occupational heat health warning systems.

Decrements in Logical Reasoning Performance under Conditions of Sleep Loss and Physical Exercise: The Factor of Sentence Complexity

1985 ◽  
Vol 61 (3_suppl) ◽  
pp. 1179-1188 ◽  
Author(s):  
David H. Ryman ◽  
Paul Naitoh ◽  
Carl E. Englund
Keyword(s):  
Physical Exercise ◽  
Sleep Loss ◽  
Logical Reasoning ◽  
Cognitive Changes ◽  
Sentence Complexity ◽  
Percent Correct ◽  
Complex Sentences ◽  
Complex Information ◽  
Reasoning Test ◽  
Simple Sentences

Baddeley's Logical Reasoning Test was used in a series of Sustained Operations (SUSOP) studies involving 100 US Matine Corps enlisted subjects, to assess the effects of sleep loss and long-term physical exercise on the ability to process complex information. The percent correct answers to the eight Logical Reasoning sentence types involving different voice (active vs passive), use of negatives, and outcome (true vs false) were analyzed over three days across three levels of exercise and rest conditions in the seven studies. A multivariate analysis of variance indicated no differences on the baseline day among the seven studies. Analyses on the baseline day and throughout the next two continuous workdays (CWs) showed consistently higher percent correct for the actively worded than for the passively worded sentences. The sleep loss over the two CWs resulted in a significant decrease in percent correct for the statements which had active wording. Sleep loss had no effect on statements with passive wording. There were no differences in comprehension between groups which had different rest conditions (no rest, 3- or 4-hr. nap, 8-hr. sleep) between the two CWs for any of the sentences; and there was no recovery from pretest to postrest. Fatigue due to exercise during either CW had no effect on comprehension for any of the sentence types. The sleep loss effects on comprehension seem due to a lessening of the attention given to those more simple sentences in active voice, whereas increased arousal may have been elicited by the more complex sentences in passive voice. The increased attention to the passive statements may have overcome the effects of sleep loss. The present study shows the usefulness of analyzing responses to the logical reasoning test by sentence complexity for indicating selective cognitive changes in the processing of information.

A Field Evaluation of Construction Workers’ Activity, Hydration Status, and Heat Strain in the Extreme Summer Heat of Saudi Arabia

2020 ◽  
Vol 64 (5) ◽  
pp. 522-535 ◽  
Author(s):  
Mohammed Al-Bouwarthan ◽  
Margaret M Quinn ◽  
David Kriebel ◽  
David H Wegman
Keyword(s):  
Heart Rate ◽  
Saudi Arabia ◽  
Heat Stress ◽  
Heat Exposure ◽  
Heat Strain ◽  
Construction Workers ◽  
Hydration Status ◽  
Summer Heat ◽  
Cardiovascular Strain ◽  
Indoor And Outdoor

Abstract Objectives Assess the impact of summer heat exposure (June–September) on residential construction workers in Al-Ahsa, Saudi Arabia by evaluating (i) heart rate (HR) responses, hydration status, and physical workload among workers in indoor and outdoor construction settings, (ii) factors related to physiological responses to work in hot conditions, and (iii) how well wet-bulb globe temperature-based occupational exposure limits (WBGTOELs) predict measures of heat strain. Methods Twenty-three construction workers (plasterers, tilers, and laborers) contributed 260 person-days of monitoring. Workload energy expenditure, HR, fluid intake, and pre- and postshift urine specific gravity (USG) were measured. Indoor and outdoor heat exposures (WBGT) were measured continuously and a WBGTOEL was calculated. The effects of heat exposure and workload on heart rate reserve (HRR), a measure of cardiovascular strain, were examined with linear mixed models. A metric called ‘heat stress exceedance’ (HSE) was constructed to summarize whether the environmental heat exposure (WBGT) exceeded the heat stress exposure limit (WBGTOEL). The sensitivity and specificity of the HSE as a predictor of cardiovascular strain (HRR ≥30%) were determined. Results The WBGTOEL was exceeded frequently, on 63 person-days indoors (44%) and 91(78%) outdoors. High-risk HRR occurred on 26 and 36 person-days indoors and outdoors, respectively. The HSE metric showed higher sensitivity for HRR ≥30% outdoors (89%) than indoors (58%) and greater specificity indoors (59%) than outdoors (27%). Workload intensity was generally moderate, with light intensity work more common outdoors. The ability to self-pace work was associated with a lower frequency of HRR ≥30%. USG concentrations indicated that workers began and ended their shifts dehydrated (USG ≥1.020). Conclusions Construction work where WBGTOEL is commonly exceeded poses health risks. The ability of workers to self-pace may help reduce risks.

Colorado Logging Accidents: 1984-1988. Is it Safe in the Woods?

1990 ◽  
Vol 5 (4) ◽  
pp. 132-135 ◽  
Author(s):  
Timothy R. Longwell ◽  
Dennis L. Lynch
Keyword(s):  
Safety Training ◽  
Economic Stress ◽  
Truck Drivers ◽  
Protective Equipment ◽  
Workers Compensation ◽  
Accident Severity ◽  
Highly Correlated ◽  
Harvesting Costs ◽  
Compensation Costs

Abstract The number of logging accidents in Colorado during 1984-1988 contributed to escalating workers' compensation rates creating economic stress in the industry. This study was designed to help both industry and agency personnel identify who was having accidents, why accidents were occurring, and how much the accidents cost. The study concluded that 60% of the accidents occurred to persons employed for fewer than 6 months. The jobs with the highest accident frequencies were chainsaw operators (68%), equipment operators (12%), and truck drivers (10%). Timber falling and limbing were the most hazardous activities, with 35% and 23% of the accidents respectively. Falling tops, snags, or dead branches and chainsaw kickback were the leading injury agents in the felling and limbing operation. Use of protective equipment and formal safety training were, for the most part, absent during this period. Medical and compensation costs were not highly correlated with accident severity. Accident costs directly increase harvesting costs and may decrease the amount paid for stumpage. West J. Appl. For. 5(4):00-00.

scholarly journals Microscopic sperm head damage and abnormalities as heat stress indicators in Australian Merino rams (Ovis aries) in Northern Patagonia, Argentina

2018 ◽  
Vol 55 (1) ◽  
pp. 1
Author(s):  
María Fernanda López Armengol ◽  
Natalia Rubio ◽  
Guillermo Ariel Sabino ◽  
Nadia Soledad Bérgamo ◽  
Valeria Pelufo
Keyword(s):  
Heat Stress ◽  
Sperm Head ◽  
Ovis Aries ◽  
Stress Indicators ◽  
Northern Patagonia ◽  
Australian Merino

Na Patagônia Norte, os ovinos têm sua estação de acasalamento iniciada em 15 de março, portanto, ficam sujeitos às temperaturas do verão. A exposição de carneiros a estresse térmico aumenta a prevalência de danos microscópicos e anomalias morfológicas nos espermatozoides, que implica uma redução na fertilidade. Este trabalho avaliou a capacidade adaptativa de carneiros Merino Australiano com lã (N = 6) e tosquiados (N = 6): metade ficou ao ar livre e outra metade foi mantida em uma câmara climática por oito horas, durante cinco dias, chegando gradualmente a uma temperatura máxima de 40 °C. Foram analisados danos microscópicos, anormalidades e alterações ultramicroscópicas da membrana plasmática e do acrossoma da cabeça dos espermatozoides. Os resultados microscópicos confirmaram a existência de diferença significativa na porcentagem de espermatozoides sem cauda e com gota citoplasmática proximal, entre os ejaculados pós-tratamento. A temperatura afetou os carneiros tosquiados, principalmente a cabeça de seus espermatozoides, durante a espermatogênese. Alterações submicroscópicas foram observados na membrana plasmática quando ela estava presente no segmento anterior: quando não intacta, ficava ondulada ou dilatada. Quando a membrana plasmática estava ausente, o acrossoma podia se apresentar ondulado ou dilatado. Além disso, sob efeito do calor, a membrana acrossomal externa pode perder completamente seu conteúdo ou apresentar núcleo desnudo. A membrana plasmática assume uma forma ondulada pelo efeito da temperatura no epidídimo. Depois de dez semanas, a cabeça dos espermatozoides recuperou sua forma normal. Como demonstrado neste estudo, a cabeça sem cauda, as gotas citoplasmáticas proximais e as categorias ultramicroscópicas estudadas são indicadores do efeito do estresse térmico no sêmen, e os carneiros com maior cobertura de lã se adaptam melhor ao estresse por calor. Alterações de microscopia e de microscopia eletrônica de transmissão têm se mostrado excelentes indicadores de estresse por calor em carneiros Merino Australiano e podem ser ferramentas úteis para ajudar criadores de ovelhas a escolher quando começar a época de acasalamento, o que irá variar de acordo com as condições ambientais do verão.

scholarly journals Cell Membrane Stability and Relative Cell Injury in Response to Heat Stress during Early and Late Seedling Stages of Diverse Carrot (Daucus carota L.) Germplasm

HortScience ◽  
2020 ◽  
Vol 55 (9) ◽  
pp. 1446-1452 ◽  
Author(s):  
Aneela Nijabat ◽  
Adam Bolton ◽  
Muhammad Mahmood-ur-Rehman ◽  
Adeel Ijaz Shah ◽  
Rameez Hussain ◽  
...  
Keyword(s):  
Heat Stress ◽  
Cell Membrane ◽  
Heat Tolerance ◽  
Daucus Carota ◽  
Cell Injury ◽  
Membrane Stability ◽  
Seedling Stage ◽  
Stress Indicators ◽  
Cell Membrane Stability ◽  
Heat Tolerant

Heat waves occur with more regularity and they adversely affect the yield of cool season crops including carrot (Daucus carota L.). Heat stress influences various biochemical and physiological processes including cell membrane permeability. Ion leakage and increase in cell permeability are indicators of cell membrane stability and have been used to evaluate the stress tolerance response in numerous crops and inform plant breeders for improving heat tolerance. No study has been published about the effects of heat stress on cell membrane stability and relative cell injury of carrot. Therefore, the present study was designed to estimate these stress indicators in response to heat stress at the early and late seedling developmental stages of 215 diverse accessions of wild and cultivated carrot germplasm. The article identifies the relationship between early and late stages of seedling tolerance across carrot genotypes and identifies heat-tolerant genotypes for further genetic analysis. Significant genetic variation among these stress indicators was identified with cell membrane stability and relative cell injury ranging from 6.3% to 97.3% and 2.8% to 76.6% at the early seedling stage, respectively; whereas cell membrane stability and relative cell injury ranged from 2.0% to 94.0% and 2.5% to 78.5%, respectively, at the late seedling stage under heat stress. Broad-sense heritability ranged from 0.64 to 0.91 for traits of interest under study, which indicates a relatively strong contribution of genetic factors in phenotypic variation among accessions. Heat tolerance varied widely among both wild and cultivated accessions, but the incidence of tolerance was higher in cultivated carrots than in wild carrots. The cultivated carrot accessions PI 326009 (Uzbekistan), PI 451754 (Netherlands), L2450 (USA), and PI 502654 (Pakistan) were identified as the most heat-tolerant accessions with highest cell membrane stability. This is the first evaluation of cell membrane stability and relative cell injury in response to heat stress during carrot development.

scholarly journals Hubungan antara Lingkungan Fisik dengan Kelelahan Kerja Pegawai Produksi di Pabrik Tahu Sutera Galih Dabeda

2020 ◽  
Vol 14 (1) ◽  
pp. 30
Author(s):  
Gurdani Yogisutanti ◽  
Dhony Firmansyah ◽  
Suyono Suyono
Keyword(s):  
Heat Stress ◽  
Data Analysis ◽  
P Value ◽  
Protective Equipment ◽  
Chi Square ◽  
Cross Sectional ◽  
Direct Measurements ◽  
Chi Square Test ◽  
Cross Sectional Design ◽  
The Relationship

Background: Fatigue is a workplace accident that decreased efficiency and endurance at work. This study aims to determine the factors that influence work fatigue in tofu production workers at the Galih Dabeda Silk Tofu Factory Kampung Cibuntu Bandung. Method: The research was cross sectional design and sample in the form of total sampling with a total of 80 employees. Data collection is done through interviews and direct measurements. Data analysis was performed univariately and bivariately with chi square test and the magnitude of the relationship (OR). Results: Factors related to work fatigue are noise (p-value 0,0001) and lighting (p-value 0,0001), but heat stress (p-value 0.532; OR 1.045 95%; 0.987- 1,112) did not correlate with fatigue. Conclusion: The conclusion that can be drawn from this study is the noise and lighting associated with the occurrence of work fatigue in employees in the factory know, while the heat pressure is not proven to be associated with work fatigue. Suggestions that can be recommended are to provide alternating hours of rest for 30-60 minutes to employees, use personal protective equipment as needed and drink water at least 8-10 glasses a day or 160 - 200 ml of water in one day according to their respective needs the worker.

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