Exertional Heat Illnesses and Environmental Conditions During High School Football Practices.

PubMed

Tripp, Brady L; Eberman, Lindsey E; Smith, Michael Seth

2015-10-01

Guidelines for preventing exertional heat illnesses (EHIs) during extreme heat stress should be specific to regional environments, age, and sport and should be based on evidence of reducing the risk. Each year in the United States, over 1 million high school football players practice in the August heat; however, no published data describe the incidence of EHIs in these athletes. To describe the environmental conditions and incidence of EHIs during high school football practices over a 3-month period. Descriptive epidemiology study. For a 3-month period (August-October), athletic trainers at 12 high schools in North Central Florida recorded the practice time and length, environmental conditions (wet-bulb globe temperature), and incidences of EHIs in varsity football athletes. Athletes suffered 57 total EHIs during 29,759 athlete-exposures (AEs) for the 3-month data collection period (rate = 1.92/1000 AEs). August accounted for the majority of all EHIs, with 82.5% (47/57) and the highest rate (4.35/1000 AEs). Of total heat illnesses, heat cramps accounted for 70.2% (40/57), heat exhaustion 22.8% (13/57), and heat syncope 7.0% (4/57). The odds ratio indicated that athletes in August practices that lasted longer than the recommended 3 hours were 9.84 times more likely to suffer a heat illness than those in practices lasting ≤3 hours. The highest rate of EHIs was during August. Practices in August that exceeded the recommended 3 hours were associated with a greater risk of heat illnesses. The overall rate of EHIs was lower for the high school football athletes observed in the study compared with that reported for collegiate football athletes in the region. The low rates of EHIs recorded suggest that the prevention guidelines employed by sports medicine teams are appropriate for the region and population. Team physicians and athletic trainers should employ evidence-based, region- and population-specific EHI prevention guidelines. Sports medicine teams, coaches, and athletes should be aware of the increased risk of EHIs during August practices and the risk of prolonged practices during August. © 2015 The Author(s).

Without Warning: Worker Deaths From Heat 2014-2016.

PubMed

Roelofs, Cora

2018-01-01

Worker deaths from heat exposure are unlike heat deaths in the general population; workers tend to be outside in variable temperatures and younger than sixty-five years. Climate change will increase the frequency, duration, and variability of hot temperatures. Public health warning systems, such as the Heat Index of the National Weather Service, do not generally account for workers' greater likelihood of exposure to direct sunlight or exertion. Only 28% of the 79 worker heat-related fatalities during 2014-2016 occurred on days when the National Weather Service warning would have included the possibility of fatal heat stroke. Common heat illness prevention advice ignores workers' lack of control over their ability to rest and seek cooler temperatures. Additionally, acclimatization, or phased-in work in the heat, may be less useful given temperature variability under climate change. Workers' vulnerability and context of heat exposure should inform public health surveillance and response to prevent heat illness and death.

Exercise in the Heat. II. Critical Concepts in Rehydration, Exertional Heat Illnesses, and Maximizing Athletic Performance

PubMed Central

Casa, Douglas J.

1999-01-01

Objective: To acquaint athletic trainers with the numerous interrelated components that must be considered when assisting athletes who exercise in hot environments. Useful guidelines to maximize performance and minimize detrimental health consequences are presented. Data Sources: The databases MEDLINE and SPORT Discus were searched from 1980 to 1999, with the terms. “body cooling,” “dehydration,” “exercise,” “heat illnesses,” “heat,” “fluid replacement,” “acclimatization,” “hydration,” “rehydration,” “performance,” and “intravenous,” among others. Data Synthesis: This paper provides an in-depth look at issues regarding physiologic and performance considerations related to rehydration, strategies to maximize rehydration, modes of rehydration, health consequences of exercise in the heat, heat acclimatization, body cooling techniques, and practice and competition modifications. Conclusions/Recommendations: Athletic trainers have a responsibility to ensure that athletes who exercise in hot environments are prepared to do so in an optimal manner and to act properly to avoid the potentially harmful heat illnesses that can result from exercise in the heat. PMID:16558573

Exertional heat illness: a review of the syndrome affecting racing Thoroughbreds in hot and humid climates.

PubMed

Brownlow, M A; Dart, A J; Jeffcott, L B

2016-07-01

Metabolic heat produced by Thoroughbred racehorses during racing can rapidly elevate core body temperature (1°C/min). When environmental conditions are hot and humid, the normal physiological cooling mechanisms become ineffective. The heat accumulated may exceed a critical thermal maximum (estimated to be 42°C), which may trigger a complex pathophysiological cascade with potentially lethal consequences. This syndrome has been labelled exertional heat illness (EHI). EHI is described in humans, but has not been well documented in Thoroughbred racehorses. The clinical signs described in racehorses would suggest that the pathophysiological events affecting the central nervous (CNS) and gastrointestinal systems are similar to those described in humans. Clinical signs are progressive and include signs of endotoxaemia and increasing levels of CNS dysfunction. Initially, horses that may be mildly irritable (agitated, randomly kicking out) may progress to unmanageable (disorientation, severe ataxia, falling) and ultimately convulsions, coma and death. Currently, the approach to treatment is largely empirical and involves rapid and effective cooling, administration of drugs to provide sedation, administration of non-steroidal anti-inflammatory drugs to ameliorate the effects of endotoxaemia and glucocorticoids to stabilise cell membranes and reduce the effects of inflammation on the CNS. This review provides an overview of the current knowledge about EHI in Thoroughbred racehorses, suggests a likely pathophysiology of the syndrome in horses based on the current literature on heat illness in humans and horses, and outlines current treatment strategies being used to treat racehorses with clinical signs of EHI. © 2016 Australian Veterinary Association.

Physiological responses to the menstrual cycle: implications for the development of heat illness in female athletes.

PubMed

Marsh, Susan A; Jenkins, David G

2002-01-01

Fluctuations in estrogen and progesterone during the menstrual cycle can cause changes in body systems other than the reproductive system. For example, progesterone is involved in the regulation of fluid balance in the renal tubules and innervation of the diaphragm via the phrenic nerve. However, few significant changes in the responses of the cardiovascular and respiratory systems, blood lactate, bodyweight, performance and ratings of perceived exertion are evident across the cycle. Nevertheless, substantial evidence exists to suggest that increased progesterone levels during the luteal phase cause increases in both core and skin temperatures and alter the temperature at which sweating begins during exposure to both ambient and hot environments. As heat illness is characterised by a significant increase in body temperature, it is feasible that an additional increase in core temperature during the luteal phase could place females at an increased risk of developing heat illness during this time. In addition, it is often argued that physiological gender differences such as oxygen consumption, percentage body fat and surface area-to-mass ratio place females at a higher risk of heat illness than males. This review examines various physiological responses to heat exposure during the menstrual cycle at rest and during exercise, and considers whether such changes increase the risk of heat illness in female athletes during a particular phase of the menstrual cycle.

Sickle Cell Trait and Fatal Exertional Heat Illness: Implications for Exercise-Related Death of Young Ddults

DTIC Science & Technology

2008-10-22

athletes who utilize ordinary weather reports? Alpha- Thalassemia Protects Against Exertional Mortality with Sickle Cell Trait • 30% of African...Americans have alpha- thalassemia (2-3 alpha genes instead of 4). In those with sickle cell trait the main effect is to lower the Hb S fraction below 36...expected 15 cases with alpha- thalassemia & ប% S • Two cases had Hb S < 36% , implying about a 7.5-fold protection for those with alpha thalassemia

Identification of Risk Factors for Exertional Heat Illness: A Brief Commentary on Genetic Testing

DTIC Science & Technology

2007-01-01

RYR1) gene and other genes related to disorders of skeletal muscle. Data Synthesis : EHI is a complex disorder wherein physiological, environmental, and...a life-threatening, hypermetabolic syndrome, known as a fulminant MH episode; similar (rare) events can be induced by high environmental temperatures

Relieving thermal discomfort: Effects of sprayed L-menthol on perception, performance, and time trial cycling in the heat.

PubMed

Barwood, M J; Corbett, J; Thomas, K; Twentyman, P

2015-06-01

L-menthol stimulates cutaneous thermoreceptors and induces cool sensations improving thermal comfort, but has been linked to heat storage responses; this could increase risk of heat illness during self-paced exercise in the heat. Therefore, L-menthol application could lead to a discrepancy between behavioral and autonomic thermoregulatory drivers. Eight male participants volunteered. They were familiarized and then completed two trials in hot conditions (33.5 °C, 33% relative humidity) where their t-shirt was sprayed with CONTROL-SPRAY or MENTHOL-SPRAY after 10 km (i.e., when they were hot and uncomfortable) of a 16.1-km cycling time trial (TT). Thermal perception [thermal sensation (TS) and comfort (TC)], thermal responses [rectal temperature (Trec ), skin temperature (Tskin )], perceived exertion (RPE), heart rate, pacing (power output), and TT completion time were measured. MENTHOL-SPRAY made participants feel cooler and more comfortable and resulted in lower RPE (i.e., less exertion) yet performance was unchanged [TT completion: CONTROL-SPRAY 32.4 (2.9) and MENTHOL-SPRAY 32.7 (3.0) min]. Trec rate of increase was 1.40 (0.60) and 1.45 (0.40) °C/h after CONTROL-SPRAY and MENTHOL-SPRAY application, which were not different. Spraying L-menthol toward the end of self-paced exercise in the heat improved perception, but did not alter performance and did not increase heat illness risk. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Exertional Heat Illness in American Football Players: When Is the Risk Greatest?

PubMed Central

Cooper, Earl R.; Ferrara, Michael S.; Casa, Douglas J.; Powell, John W.; Broglio, Steven P.; Resch, Jacob E.; Courson, Ronald W.

2016-01-01

Context: Knowledge about the specific environmental and practice risks to participants in American intercollegiate football during preseason practices is limited. Identifying risks may mitigate occurrences of exertional heat illness (EHI). Objective: To evaluate the associations among preseason practice day, session number, and wet bulb globe temperature (WBGT) and the incidence of EHI. Design: Descriptive epidemiology study. Setting: Sixty colleges and universities representing 5 geographic regions of the United States. Patients or Other Participants: National Collegiate Athletic Association football players. Main Outcome Measure(s): Data related to preseason practice day, session number, and WBGT. We measured WBGT every 15 minutes during the practice sessions and used the mean WBGT from each session in the analysis. We recorded the incidence of EHIs and calculated the athlete-exposures (AEs). Results: A total of 553 EHI cases and 365 810 AEs were reported for an overall EHI rate of 1.52/1000 AEs (95% confidence interval [CI] = 1.42, 1.68). Approximately 74% (n = 407) of the reported EHI cases were exertional heat cramps (incidence rate = 1.14/1000 AEs; 95% CI = 1.03, 1.25), and about 26% (n = 146) were a combination of exertional heat syncope and heat exhaustion (incidence rate = 0.40/1000 AEs; 95% CI = 0.35, 0.48). The highest rate of EHI occurred during the first 14 days of the preseason period, and the greatest risk was during the first 7 days. The risk of EHI increased substantially when the WBGT was 82.0°F (27.8°C) or greater. Conclusions: We found an increased rate of EHI during the first 14 days of practice, especially during the first 7 days. When the WBGT was greater than 82.0°F (27.8°C), the rate of EHI increased. Sports medicine personnel should take all necessary preventive measures to reduce the EHI risk during the first 14 days of practice and when the environmental conditions are greater than 82.0°F (27.8°C) WBGT. PMID:27505271

Preventive measures and lifestyle habits against exertional heat illness in radiation decontamination workers.

PubMed

Endo, Shota; Kakamu, Takeyasu; Sato, Sei; Hidaka, Tomoo; Kumagai, Tomohiro; Nakano, Shinichi; Koyama, Kikuo; Fukushima, Tetsuhito

2017-09-28

The aim of this study was to reveal the current state of preventive measures and lifestyle habits against heat illness in radiation decontamination workers and to examine whether young radiation decontamination workers take less preventive measures and have worse lifestyle habits than the elder workers. This was a cross-sectional study. Self-administered questionnaires were sent to 1,505 radiation decontamination workers in Fukushima, Japan. Five hundred fifty-eight men who replied and answered all questions were included in the statistical analysis. The questionnaire included age, duration of decontamination work, previous occupation, lifestyle habit, and preventive measures for heat illness. We classified age of the respondents into five groups: <30, 30-39, 40-49, 50-59, and ≥60 years and defined the workers under 30 years of age as young workers. Logistic regression analysis was used to reveal the factors associated with each lifestyle habit and preventive measures. In comparison with young workers, 50-59-year-old workers were significantly associated with refraining from drinking alcohol. Workers 40 years of age or older were significantly associated with cooling their bodies with refrigerant. Furthermore, 30-39-year-old workers and 40-49-year-old workers were significantly associated with adequate consumption of water compared to young workers. The results of our study suggests that young decontamination workers are more likely to have worse lifestyle habits and take insufficient preventive measures for heat illness. This may be the cause of higher incidence of heat illness among young workers.

Elevation of cardiac troponin I during non-exertional heat-related illnesses in the context of a heatwave

PubMed Central

2010-01-01

Introduction The prognostic value of cardiac troponin I (cTnI) in patients having a heat-related illness during a heat wave has been poorly documented. Methods In a post hoc analysis, we evaluated 514 patients admitted to emergency departments during the August 2003 heat wave in Paris, having a core temperature >38.5°C and who had analysis of cTnI levels. cTnI was considered as normal, moderately elevated (abnormality threshold to 1.5 ng.mL-1), or severely elevated (>1.5 ng.mL-1). Patients were classified according to our previously described risk score (high, intermediate, and low-risk of death). Results Mean age was 84 ± 12 years, mean body temperature 40.3 ± 1.2°C. cTnI was moderately elevated in 165 (32%) and severely elevated in 97 (19%) patients. One-year survival was significantly decreased in patients with moderate or severe increase in cTnI (24 and 46% vs 58%, all P < 0.05). Using logistic regression, four independent variables were associated with an elevated cTnI: previous coronary artery disease, Glasgow coma scale <12, serum creatinine >120 μmol.L-1, and heart rate >110 bpm. Using Cox regression, only severely elevated cTnI was an independent prognostic factor (hazard ratio 1.93, 95% confidence interval 1.35 to 2.77) when risk score was taken into account. One-year survival was decreased in patients with elevated cTnI only in high risk patients (17 vs 31%, P = 0.04). Conclusions cTnI is frequently elevated in patients with non-exertional heat-related illnesses during a heat wave and is an independent risk factor only in high risk patients where severe increase (>1.5 ng.mL-1) indicates severe myocardial damage. PMID:20507603

Exertional rhabdomyolysis in a collegiate american football player after preventive cold-water immersion: a case report.

PubMed

Kahanov, Leamor; Eberman, Lindsey E; Wasik, Mitchell; Alvey, Thurman

2012-01-01

To describe a case of exertional rhabdomyolysis in a collegiate American football player after preventive coldwater immersion. A healthy man (19 years old) participated in full-contact football practice followed by conditioning (2.5 hours). After practice, he entered a coach-mandated postpractice cold-water immersion and had no signs of heat illness before developing leg cramps, for which he presented to the athletic training staff. After 10 minutes of repeated stretching, massage, and replacement of electrolyte-filled fluids, he was transported to the emergency room. Laboratory tests indicated a creatine kinase (CK) level of 2545 IU/L (normal range, 45-260 IU/L), CK-myoglobin fraction of 8.5 ng/mL (normal < 6.7 ng/mL), and CK-myoglobin relative index of 30% (normal range, 25%-30%). Myoglobin was measured at 499 ng/mL (normal = 80 ng/mL). The attending physician treated the athlete with intravenous fluids. Exercise-associated muscle cramps, dehydration, exertional rhabdomyolysis. The patient was treated with rest and rehydration. One week after the incident, he began biking and swimming. Eighteen days later, the patient continued to demonstrate elevated CK levels (527 IU/L) but described no other symptoms and was allowed to return to football practice as tolerated. Two months after the incident, his CK level remained high (1900 IU/L). The athlete demonstrated no signs of heat illness upon entering the cold-water immersion but experienced severe leg cramping after immersion, resulting in a diagnosis of exertional rhabdomyolysis. Previously described cases have not linked cold-water immersion with the pathogenesis of rhabdomyolysis. In this football player, CK levels appeared to be a poor indicator of rhabdomyolysis. Our patient demonstrated no other signs of the illness weeks after the incident, yet his elevated CK levels persisted. Cold-water immersion immediately after exercise should be monitored by the athletic training staff and may not be appropriate to prevent muscle damage, given the lack of supporting evidence.

A 3-D Mathematical Model to Identify Organ-Specific Risks in Rats During Thermal Stress

DTIC Science & Technology

2013-01-01

increases in rat core temperature in antic- ipation of the lights-off (active) period at 1800. This response is anticipatory of the active period when...Epidemiology of hospitalizations and deaths from heat illness in soldiers. Med Sci Sports Exerc 37: 1338–1344, 2005. 11. Casa DJ, Armstrong LE, Ganio...MS, Yeargin SW. Exertional heat stroke in competitive athletes. Curr Sports Med Rep 4: 309–317, 2005. 12. Chang CK, Chang CP, Chiu WT, Lin MT

Preventive measures and lifestyle habits against exertional heat illness in radiation decontamination workers

PubMed Central

Endo, Shota; Kakamu, Takeyasu; Sato, Sei; Hidaka, Tomoo; Kumagai, Tomohiro; Nakano, Shinichi; Koyama, Kikuo; Fukushima, Tetsuhito

2017-01-01

Objectives: The aim of this study was to reveal the current state of preventive measures and lifestyle habits against heat illness in radiation decontamination workers and to examine whether young radiation decontamination workers take less preventive measures and have worse lifestyle habits than the elder workers. Methods: This was a cross-sectional study. Self-administered questionnaires were sent to 1,505 radiation decontamination workers in Fukushima, Japan. Five hundred fifty-eight men who replied and answered all questions were included in the statistical analysis. The questionnaire included age, duration of decontamination work, previous occupation, lifestyle habit, and preventive measures for heat illness. We classified age of the respondents into five groups: <30, 30-39, 40-49, 50-59, and ≥60 years and defined the workers under 30 years of age as young workers. Logistic regression analysis was used to reveal the factors associated with each lifestyle habit and preventive measures. Results: In comparison with young workers, 50-59-year-old workers were significantly associated with refraining from drinking alcohol. Workers 40 years of age or older were significantly associated with cooling their bodies with refrigerant. Furthermore, 30-39-year-old workers and 40-49-year-old workers were significantly associated with adequate consumption of water compared to young workers. Conclusion: The results of our study suggests that young decontamination workers are more likely to have worse lifestyle habits and take insufficient preventive measures for heat illness. This may be the cause of higher incidence of heat illness among young workers. PMID:28794393

Females exposed to 24 h of sleep deprivation do not experience greater physiological strain, but do perceive heat illness symptoms more severely, during exercise-heat stress.

PubMed

Relf, Rebecca; Willmott, Ashley; Mee, Jessica; Gibson, Oliver; Saunders, Arron; Hayes, Mark; Maxwell, Neil

2018-02-01

There is limited and inconclusive evidence surrounding the physiological and perceptual responses to heat stress while sleep deprived, especially for females. This study aimed to quantify the effect of 24 h sleep deprivation on physiological strain and perceptual markers of heat-related illness in females. Nine females completed two 30-min heat stress tests (HST) separated by 48 h in 39°C, 41% relative humidity at a metabolic heat production of 10 W · kg -1 . The non-sleep deprived HST was followed by the sleep deprivation (SDHST) trial for all participants during the follicular phase of the menstrual cycle. Physiological and perceptual measures were recorded at 5 min intervals during the HSTs. On the cessation of the HSTs, heat illness symptom index (HISI) was completed. HISI scores increased after sleep deprivation by 28 ± 16 versus 20 ± 16 (P = 0.01). Peak (39.40 ± 0.35°C vs. 39.35 ± 0.33°C) and change in rectal temperature (1.91 ± 0.21 vs. 1.93 ± 0.34°C), and whole body sweat rate (1.08 ± 0.31 vs. 1.15 ± 0.36 L · h -1 ) did not differ (P > 0.05) between tests. No difference was observed in peak, nor rise in: heart rate, mean skin temperature, perceived exertion or thermal sensation during the HSTs. Twenty-four hours sleep deprivation increased perceptual symptoms associated with heat-related illness; however, no thermoregulatory alterations were observed.

Exertional Rhabdomyolysis in a Collegiate American Football Player After Preventive Cold-Water Immersion: A Case Report

PubMed Central

Kahanov, Leamor; Eberman, Lindsey E.; Wasik, Mitchell; Alvey, Thurman

2012-01-01

Objective: To describe a case of exertional rhabdomyolysis in a collegiate American football player after preventive cold-water immersion. Background: A healthy man (19 years old) participated in full-contact football practice followed by conditioning (2.5 hours). After practice, he entered a coach-mandated post-practice cold-water immersion and had no signs of heat illness before developing leg cramps, for which he presented to the athletic training staff. After 10 minutes of repeated stretching, massage, and replacement of electrolyte-filled fluids, he was transported to the emergency room. Laboratory tests indicated a creatine kinase (CK) level of 2545 IU/L (normal range, 45–260 IU/L), CK-myoglobin fraction of 8.5 ng/mL (normal < 6.7 ng/mL), and CK-myoglobin relative index of 30% (normal range, 25%– 30%). Myoglobin was measured at 499 ng/mL (normal = 80 ng/mL). The attending physician treated the athlete with intravenous fluids. Differential Diagnosis: Exercise-associated muscle cramps, dehydration, exertional rhabdomyolysis. Treatment: The patient was treated with rest and rehydration. One week after the incident, he began biking and swimming. Eighteen days later, the patient continued to demonstrate elevated CK levels (527 IU/L) but described no other symptoms and was allowed to return to football practice as tolerated. Two months after the incident, his CK level remained high (1900 IU/L). Uniqueness: The athlete demonstrated no signs of heat illness upon entering the cold-water immersion but experienced severe leg cramping after immersion, resulting in a diagnosis of exertional rhabdomyolysis. Previously described cases have not linked cold-water immersion with the pathogenesis of rhabdomyolysis. Conclusions: In this football player, CK levels appeared to be a poor indicator of rhabdomyolysis. Our patient demonstrated no other signs of the illness weeks after the incident, yet his elevated CK levels persisted. Cold-water immersion immediately after exercise should be monitored by the athletic training staff and may not be appropriate to prevent muscle damage, given the lack of supporting evidence. PMID:22488291

Extracellular and cellular Hsp72 differ as biomarkers in acute exercise/environmental stress and recovery.

PubMed

Lee, E C-H; Muñoz, C X; McDermott, B P; Beasley, K N; Yamamoto, L M; Hom, L L; Casa, D J; Armstrong, L E; Kraemer, W J; Anderson, J M; Maresh, C M

2017-01-01

Stress-inducible Hsp72 is a potential biomarker to track risk of exertional heat illness during exercise/environmental stress. Characterization of extracellular (eHsp72) vs cellular Hsp72 (iHsp72) responses is required to define the appropriate use of Hsp72 as a reliable biomarker. In each of four repeat visits, participants (n = 6 men, 4 trials; total n = 24): (a) passively dehydrated overnight, (b) exercised (2 h) with no fluid in a hot, humid environmental chamber, (c) rested and rehydrated (1 h), (d) maximally exercised for 0.5 h, and (e) returned after 24 h of at-home recovery and rehydration. We measured rectal temperature, hydration status (% body mass loss, urine markers, serum osmolality), and Hsp72 (ELISA, flow cytometry. eHsp72 (circulating) and iHsp72 (CD3 + PBMCs) correlated (P < 0.05) with markers of heat, exercise, and dehydration stresses. eHsp72 immediately post-exercise (>15% above baseline, P < 0.05) decreased back to baseline levels by 1 h post-exercise, but iHsp72 expression continued to rise and remained elevated 24 h post-exercise (~2.5-fold baseline, P < 0.05). These data suggest that in addition to the classic physiological biomarkers of exercise heat stress, using cellular Hsp72 as an indicator of lasting effects of stress into recovery may be most appropriate for determining long-term effects of stress on risk for exertional heat illness. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

American football and fatal exertional heat stroke: a case study of Korey Stringer.

PubMed

Grundstein, Andrew; Knox, John A; Vanos, Jennifer; Cooper, Earl R; Casa, Douglas J

2017-08-01

On August 1, 2001, Korey Stringer, a Pro Bowl offensive tackle for the Minnesota Vikings, became the first and to date the only professional American football player to die from exertional heat stroke (EHS). The death helped raise awareness of the dangers of exertional heat illnesses in athletes and prompted the development of heat safety policies at the professional, collegiate, and interscholastic levels. Despite the public awareness of this death, no published study has examined in detail the circumstances surrounding Stringer's fatal EHS. Using the well-documented details of the case, our study shows that Stringer's fatal EHS was the result of a combination of physiological limitations, organizational and treatment failings, and extreme environmental conditions. The COMfort FormulA (COMFA) energy budget model was used to assess the relative importance of several extrinsic factors on Stringer's EHS, including weather conditions, clothing insulation, and activity levels. We found that Stringer's high-intensity training in relation to the oppressive environmental conditions was the most prominent factor in producing dangerous, uncompensable heat stress conditions and that the full football uniform played a smaller role in influencing Stringer's energy budget. The extreme energy budget levels that led to the fatal EHS would have been avoided according to our modeling through a combination of reduced intensity and lower clothing insulation. Finally, a long delay in providing medical treatment made the EHS fatal. These results highlight the importance of modern heat safety guidelines that provide controls on extrinsic factors, such as the adjustment of duration and intensity of training along with protective equipment modifications based on environmental conditions and the presence of an emergency action plan focused on rapid recognition and immediate on-site aggressive cooling of EHS cases.

American football and fatal exertional heat stroke: a case study of Korey Stringer

NASA Astrophysics Data System (ADS)

Grundstein, Andrew; Knox, John A.; Vanos, Jennifer; Cooper, Earl R.; Casa, Douglas J.

2017-08-01

On August 1, 2001, Korey Stringer, a Pro Bowl offensive tackle for the Minnesota Vikings, became the first and to date the only professional American football player to die from exertional heat stroke (EHS). The death helped raise awareness of the dangers of exertional heat illnesses in athletes and prompted the development of heat safety policies at the professional, collegiate, and interscholastic levels. Despite the public awareness of this death, no published study has examined in detail the circumstances surrounding Stringer's fatal EHS. Using the well-documented details of the case, our study shows that Stringer's fatal EHS was the result of a combination of physiological limitations, organizational and treatment failings, and extreme environmental conditions. The COMfort FormulA (COMFA) energy budget model was used to assess the relative importance of several extrinsic factors on Stringer's EHS, including weather conditions, clothing insulation, and activity levels. We found that Stringer's high-intensity training in relation to the oppressive environmental conditions was the most prominent factor in producing dangerous, uncompensable heat stress conditions and that the full football uniform played a smaller role in influencing Stringer's energy budget. The extreme energy budget levels that led to the fatal EHS would have been avoided according to our modeling through a combination of reduced intensity and lower clothing insulation. Finally, a long delay in providing medical treatment made the EHS fatal. These results highlight the importance of modern heat safety guidelines that provide controls on extrinsic factors, such as the adjustment of duration and intensity of training along with protective equipment modifications based on environmental conditions and the presence of an emergency action plan focused on rapid recognition and immediate on-site aggressive cooling of EHS cases.

Self-reported post-exertional fatigue in Gulf War veterans: roles of autonomic testing

PubMed Central

Li, Mian; Xu, Changqing; Yao, Wenguo; Mahan, Clare M.; Kang, Han K.; Sandbrink, Friedhelm; Zhai, Ping; Karasik, Pamela A.

2014-01-01

To determine if objective evidence of autonomic dysfunction exists from a group of Gulf War veterans with self-reported post-exertional fatigue, we evaluated 16 Gulf War ill veterans and 12 Gulf War controls. Participants of the ill group had self- reported, unexplained chronic post-exertional fatigue and the illness symptoms had persisted for years until the current clinical study. The controls had no self-reported post-exertional fatigue either at the time of initial survey nor at the time of the current study. We intended to identify clinical autonomic disorders using autonomic and neurophysiologic testing in the clinical context. We compared the autonomic measures between the 2 groups on cardiovascular function at both baseline and head-up tilt, and sudomotor function. We identified 1 participant with orthostatic hypotension, 1 posture orthostatic tachycardia syndrome, 2 distal small fiber neuropathy, and 1 length dependent distal neuropathy affecting both large and small fiber in the ill group; whereas none of above definable diagnoses was noted in the controls. The ill group had a significantly higher baseline heart rate compared to controls. Compound autonomic scoring scale showed a significant higher score (95% CI of mean: 1.72–2.67) among ill group compared to controls (0.58–1.59). We conclude that objective autonomic testing is necessary for the evaluation of self-reported, unexplained post-exertional fatigue among some Gulf War veterans with multi-symptom illnesses. Our observation that ill veterans with self-reported post-exertional fatigue had objective autonomic measures that were worse than controls warrants validation in a larger clinical series. PMID:24431987

Implementing exertional heat illness prevention strategies in US high school football.

PubMed

Kerr, Zachary Y; Marshall, Stephen W; Comstock, R Dawn; Casa, Douglas J

2014-01-01

Approximately 6500 high school football athletes are treated annually for exertional heat illness (EHI). In 2009, the National Athletic Trainers Association (NATA)-led Inter-Association Task Force (NATA-IATF) released preseason heat acclimatization guidelines to help athletes become accustomed to environmental factors contributing to EHI. This study examines compliance with NATA-IATF guidelines and related EHI prevention strategies. The study used a cross-sectional survey completed by 1142 certified athletic trainers (AT), which captured compliance with 17 NATA-IATF guidelines and EHI prevention strategies in high school football during the 2011 preseason. On average, AT reported football programs complying with 10.4 NATA-IATF guidelines (SD = 3.2); 29 AT (2.5%) reported compliance with all 17. Guidelines with the lowest compliance were as follows: "Single-practice days consisted of practice no more than three hours in length" (39.7%); and "During days 3-5 of acclimatization, only helmets and shoulder pads should be worn" (39.0%). An average of 7.6 EHI prevention strategies (SD = 2.5) were used. Common EHI prevention strategies were as follows: having ice bags/cooler available (98.5%) and having a policy with written instructions for initiating emergency medical service response (87.8%). Programs in states with mandated guidelines had higher levels of compliance with guidelines and greater prevalence of EHI prevention strategies. A low proportion of surveyed high school football programs fully complied with all 17 NATA-IATF guidelines. However, many EHI prevention strategies were voluntarily implemented. State-level mandated EHI prevention guidelines may increase compliance with recognized best practices recommendations. Ongoing longitudinal monitoring of compliance is also recommended.

Hydration and thermal strain during tennis in the heat.

PubMed

Bergeron, Michael F

2014-04-01

Competitive tennis in the heat can prompt substantial sweat losses and extensive consequent body water and electrolyte deficits, as well as a level of thermal strain that considerably challenges a player's physiology, perception of effort, and on-court well-being and performance. Adequate hydration and optimal performance can be notably difficult to maintain when multiple same-day matches are played on successive days in hot weather. Despite the recognised effects of the heat, much more research needs to be carried out to better appreciate the broader scope and full extent of the physiological demands and hydration and thermal strain challenges facing junior and adult players in various environments, venues and competition scenarios. However, certain recommendations of best practices should be emphasised to minimise exertional heat illness risk and improve player safety, well-being and on-court performance.

Does Pre-Cooling With Whole-Body Immersion Affect Thermal Sensation or Perceived Exertion?: A Critically-Appraised Topic.

PubMed

Wohlfert, Timothy M; Miller, Kevin C

2018-02-21

Clinical Scenario: Exertional heat stroke (EHS) is a potentially deadly heat illness and poses a significant health risk to athletes; EHS survival rates are near 100% if properly recognized and treated. 1 Whole body cold water immersion (CWI) is the most effective method of lowering body core temperature. 2 Precooling (PC) with CWI before exercise may prevent severe hyperthermia and/or EHS by increasing the body's overall heat-storage capacity. 3 However, PC may also alter athletes' perception of how hot they feel or how hard they are exercising. Consequently, they may be unable to accurately perceive their body core temperature or how hard they are working which may predispose them to severe hyperthermia or EHS. Does PC with whole-body CWI affect thermal sensation (TS) or rating of perceived exertion (RPE) during exercise in the heat? In four studies, 4-7 RPE during exercise ranged from 12 ± 2 to 20 ± 3 with no clinically meaningful differences between PC and control trials. Thermal sensation scores ranged from 2 ± 1 to 8 ± 0.5 in control trials and from 2 ± 1 to 7.5 ± 0.5 during PC trials. Clinical Bottom Line: Precooling did not cause clinically-meaningful differences in RPE or TS during exercise. It is unlikely PC would predispose athletes to EHS by altering perceptions of exercise intensity or body core temperature. Strength of Recommendation: None of the reviewed studies 4-7 (all level 2 studies with PEDro scores ≥5) suggest PC with CWI influences RPE or TS in exercising males.

Heat strain during military training activities: The dilemma of balancing force protection and operational capability.

PubMed

Hunt, Andrew P; Billing, Daniel C; Patterson, Mark J; Caldwell, Joanne N

2016-01-01

Military activities in hot environments pose 2 competing demands: the requirement to perform realistic training to develop operational capability with the necessity to protect armed forces personnel against heat-related illness. To ascertain whether work duration limits for protection against heat-related illness restrict military activities, this study examined the heat strain and risks of heat-related illness when conducting a military activity above the prescribed work duration limits. Thirty-seven soldiers conducted a march (10 km; ∼5.5 km h -1 ) carrying 41.8 ± 3.6 kg of equipment in 23.1 ± 1.8°C wet-bulb globe temperature. Body core temperature was recorded throughout and upon completion, or withdrawal, participants rated their severity of heat-related symptoms. Twenty-three soldiers completed the march in 107 ± 6.4 min (Completers); 9 were symptomatic for heat exhaustion, withdrawing after 71.6 ± 10.1 min (Symptomatic); and five were removed for body core temperature above 39.0°C (Hyperthermic) after 58.4 ± 4.5 min. Body core temperature was significantly higher in the Hyperthermic (39.03 ± 0.26°C), than Symptomatic (38.34 ± 0.44°C; P = 0.007 ) and Completers (37.94 ± 0.37°C; P<0.001 ) after 50 min. Heat-related symptom severity was significantly higher among Symptomatic (28.4 ± 11.8) compared to Completers (15.0 ± 9.8, P = 0.006 ) and Hyperthermic (13.0 ± 9.6, P = 0.029 ). The force protection provided by work duration limits may be preventing the majority of personnel from conducting activities in hot environments, thereby constraining a commander's mandate to develop an optimised military force. The dissociation between heat-related symptoms and body core temperature elevation suggests that the physiological mechanisms underpinning exhaustion during exertional heat stress should be re-examined to determine the most appropriate physiological criteria for prescribing work duration limits.

Efficacy of Liquid, Air, and Phase Change Material Torso Cooling During Light Exercise While Wearing NBC Clothing

DTIC Science & Technology

1998-03-01

and Thermal Comfort 6 Blood Sampling 6 Statistical Analyses 6 RESULTS 7 Indices of Hydration Status 7 Liquid-Cooling and PCM Cooling Vests...of Uncooled Sites 12 Vapour Pressure 12 Ratings of Thermal Comfort and Perceived Exertion 18 Indices of Heat Tolerance 18 DISCUSSION 20...ill Figures 8A and B Changes in ratings of thermal comfort of the torso and whole body during light exercise at 40°C and 30% relative humidity while

Within-year Exertional Heat Illness Incidence in U.S. Army Soldiers, 2008-2012

DTIC Science & Technology

2015-06-01

index (MDI;(17)) were created. Wind speed (in kph) was calculated as wind speed (in mph)*1.61. Wind chill was calculated for all climate samples...downloaded from the NOAA website, new variables for wind speed (converted from mph to kph), wind chill , minimum temperature, and modified discomfort...Windspeed_Kph** 0.16 + 0.3965 * DryBulbCelsius * Windspeed_Kph ** 0.16. Dry bulb temperatures (in °C) and wind chill temperatures (in °C) were

Susceptibility to exertional heat illness and hospitalisation risk in UK military personnel

PubMed Central

Stacey, Michael J; Parsons, Iain T; Woods, David R; Taylor, Peter N; Ross, David; J Brett, Stephen

2015-01-01

Background Susceptibility to exertional heat illness (EHI) is considered multifactorial in nature. The aims of this study were to (1) review traditional susceptibility factors identified in cases of EHI and (2) determine how they are related to risk of hospitalisation. Methods Review of an electronic database of EHI reported in the British Army between 1 September 2007 and 31 December 2014. Cases were categorised by demographic, situational and susceptibility variables. Univariate and multivariate logistic regression was performed for the OR for hospitalisation by risk factor. Results 361 reports were included in the analysis. 33.5% of cases occurred in hot climates, 34.6% in temperate climates during summer months and 31.9% in temperate climates outside of summer months. Traditional susceptibility factors were reported in 193 but entirely absent from 168 cases. 137 cases (38.0%) were admitted to hospital. Adjusted OR for hospitalisation was lower for recruits (OR 0.42, 95% CI 0.18 to 0.99, p<0.05) and for personnel wearing occlusive dress (OR 0.56, 95% CI 0.34 to 0.93, p<0.05) or unacclimatised to heat (OR 0.31, 95% CI 0.15 to 0.66, p<0.01). Conclusions The global, year-round threat of EHI is highlighted. Absence of susceptibility factors in nearly half of reports highlights the challenge of identifying EHI-prone individuals. Paradoxical association of traditional susceptibility factors with reduced hospitalisation risk may reflect the contemporary contexts in which severe EHI occurs. These findings also suggest a need for better evidence to inform guidelines that aim to prevent severe EHI concurrent to reducing overall morbidity. PMID:27900138

Fatal Exertional Heat Stroke and American Football Players: The Need for Regional Heat-Safety Guidelines.

PubMed

Grundstein, Andrew J; Hosokawa, Yuri; Casa, Douglas J

2018-01-01

  Weather-based activity modification in athletics is an important way to minimize heat illnesses. However, many commonly used heat-safety guidelines include a uniform set of heat-stress thresholds that do not account for geographic differences in acclimatization.   To determine if heat-related fatalities among American football players occurred on days with unusually stressful weather conditions based on the local climate and to assess the need for regional heat-safety guidelines.   Cross-sectional study.   Data from incidents of fatal exertional heat stroke (EHS) in American football players were obtained from the National Center for Catastrophic Sport Injury Research and the Korey Stringer Institute.   Sixty-one American football players at all levels of competition with fatal EHSs from 1980 to 2014.   We used the wet bulb globe temperature (WBGT) and a z-score WBGT standardized to local climate conditions from 1991 to 2010 to assess the absolute and relative magnitudes of heat stress, respectively.   We observed a poleward decrease in exposure WBGTs during fatal EHSs. In milder climates, 80% of cases occurred at above-average WBGTs, and 50% occurred at WBGTs greater than 1 standard deviation from the long-term mean; however, in hotter climates, half of the cases occurred at near average or below average WBGTs.   The combination of lower exposure WBGTs and frequent extreme climatic values in milder climates during fatal EHSs indicates the need for regional activity-modification guidelines with lower, climatically appropriate weather-based thresholds. Established activity-modification guidelines, such as those from the American College of Sports Medicine, work well in the hotter climates, such as the southern United States, where hot and humid weather conditions are common.

Novel Interventions for Heat/Exercise Induced Sudden Death and Fatigue

DTIC Science & Technology

2013-10-01

mutations associated with enhanced susceptibility to Exertional Heat Stroke (EHS), Exertional Rhabdomyolysis (ER), and Malignant Hyperthermia (MH) by...reduces the probability of a hypermetabolic response in YS mice. 15. SUBJECT TERMS: Exertional Heat Stroke, Exertional Rhabdomyolysis ...and exertional rhabdomyolysis (ER) have been reported in subjects with diagnosis of Malignant Hyperthermia (MH). MH is a life- threatening

Epidemiology of Exertional Heat Illnesses in Youth, High School, and College Football.

PubMed

Yeargin, Susan W; Kerr, Zachary Y; Casa, Douglas J; Djoko, Aristarque; Hayden, Ross; Parsons, John T; Dompier, Thomas P

2016-08-01

Data on exertional heat illness (EHI) in youth football are limited and have not been compared across competition levels. This study describes the epidemiology of EHI events in youth, high school (HS), and college football in the 2012-2014 seasons. One hundred and eighteen youth teams (players age 5-14 yr), 96 HS programs (~14-18 yr), and 34 college programs (~18-23 yr) participated. During games and practices, athletic trainers recorded EHI events and athlete exposures (AE), defined as one athlete participating in one game/practice. We calculated the number of reported EHI by time in season, game/practice, and need for emergency transportation. EHI rates, risk, included rate ratios (IRR), and risk ratios (RR) with 95% confidence intervals (CI) were calculated in 2015. EHI rates for youth, HS, and college football were 1.82, 0.57, and 1.67/10,000 AE, respectively. Rates were highest during the preseason (youth: 2.76; HS: 1.47; college: 3.66/10,000 AE). Game rates were higher than practice rates in youth (4.04 vs 1.22/10,000 AE; IRR = 3.31; 95% CI, 1.75-6.26) and college (4.42 vs 1.38/10,000 AE; IRR = 3.21; 95% CI, 2.00-5.16); the practice rate was higher than the game rate in HS (0.63 vs 0.27/10,000 AE; IRR = 2.33; 95% CI, 1.01-5.38). The EHI risk was higher in college (0.9%) than in youth (0.6%; RR = 1.59; 95% CI, 1.06-2.37) and HS (0.5%; RR = 2.01; 95% CI, 1.43-2.81). Common EHI events included heat cramps (youth: 15.8%; HS: 28.6%; college: 45.6%), heat exhaustion (youth: 42.1%; HS: 32.9%; college: 20.0%), and dehydration (youth: 31.6%; HS: 28.6%; college: 28.9%). EHI risk was low. Higher preseason football EHI rates across levels emphasize developing and continually modifying preseason heat acclimatization policies. Lower EHI rates in HS games and youth practices may be attributable to night events, suggesting the importance of modifying/canceling events based on environmental conditions.

Exertional heat stroke management strategies in United States high school football.

PubMed

Kerr, Zachary Y; Marshall, Stephen W; Comstock, R Dawn; Casa, Douglas J

2014-01-01

The 5-year period of 2005-2009 saw more exertional heat stroke-related deaths in organized sports than any other 5-year period in the past 35 years. The risk of exertional heat stroke appears highest in football, particularly during the preseason. To estimate the incidence of exertional heat stroke events and assess the utilization of exertional heat stroke management strategies during the 2011 preseason in United States high school football programs. Cross-sectional study; Level of evidence, 3. A self-administered online questionnaire addressing the incidence of exertional heat stroke events and utilization of exertional heat stroke management strategies (eg, removing athlete's football equipment, calling Emergency Medical Services [EMS]) was completed in May to June 2012 by 1142 (18.0%) athletic trainers providing care to high school football athletes during the 2011 preseason. Among all respondents, 20.3% reported treating at least 1 exertional heat stroke event. An average of 0.50 ± 1.37 preseason exertional heat stroke events were treated per program. Athletic trainers responding to exertional heat stroke reported using an average of 6.6 ± 1.8 management strategies. The most common management strategies were low-level therapeutic interventions such as removing the athlete's football equipment (98.2%) and clothing (77.8%) and moving the athlete to a shaded area (91.6%). Few athletic trainers reported active management strategies such as calling EMS (29.3%) or using a rectal thermometer to check core body temperature (0.9%). Athletic trainers in states with mandated preseason heat acclimatization guidelines reported a higher utilization of management strategies such as cooling the athlete through air conditioning (90.1% vs 65.0%, respectively; P < .001), immersion in ice water (63.0% vs 45.4%, respectively; P = .01), or fans (54.3% vs 42.0%, respectively; P = .06) and monitoring the athlete's temperature (60.5% vs 46.2%, respectively; P = .04). Preseason exertional heat stroke events, which are likely to be fatal if untreated, were reported by one fifth of all athletic trainers in high school football programs. The standard of care is (and should be) to treat proactively; therefore, treatment is not a perfect proxy for incidence. Nevertheless, there is an urgent need for improved education and awareness of exertional heat stroke in high school football. Areas of improvement include the greatly increased use of rectal thermometers and immersion in ice water.

Exertional heat-related illnesses at the Grand Canyon National Park, 2004-2009.

PubMed

Noe, Rebecca S; Choudhary, Ekta; Cheng-Dobson, Jennifer; Wolkin, Amy F; Newman, Sara B

2013-12-01

The Grand Canyon National Park has approximately 4 million visitors between April and September each year. During this period, outdoor activity such as hiking is potentially hazardous owing to extreme heat, limited shade, and steep, long ascents. Given the high visitation and the public health interest in the effects of extreme heat, this study calculated morbidity rates and described heat-related illness (HRI) among visitors. We conducted a retrospective cross-sectional study from April 1 through September 30, during 2004-2009. From a review of Ranger Emergency Medical Services (EMS) incident report files, we extracted information on those that met the case definition of greater than 1 hour of outdoor heat exposure with an HRI assessment or diagnosis, HRI self-report, or signs or symptoms of HRI without another etiology noted. Visitor and temperature data were obtained from respective official sources. Grand Canyon EMS responded to 474 nonfatal and 6 fatal HRI cases, with the majority (84%) being US residents, 29% from Western states. Of the nonfatal cases, 51% were women, the median age was 43 years (range, 11-83 years), and 18% reported a cardiovascular condition. Clinical HRI assessments included dehydration (25%), heat exhaustion (23%), and suspected hyponatremia (19%). Almost all (90%) were hiking; 40% required helicopter evacuation. The highest HRI rates were seen in May. HRI remains a public health concern at the Grand Canyon. High-risk evacuations and life-threatening conditions were found. Majority were hikers, middle-aged adults, and US residents. These findings support the park's hiker HRI prevention efforts and use of park EMS data to measure HRI. Published by Elsevier Inc.

Exertional rhabdomyolysis: a clinical review with a focus on genetic influences.

PubMed

Landau, Mark E; Kenney, Kimbra; Deuster, Patricia; Campbell, William

2012-03-01

In this review, the clinical and laboratory features of exertional rhabdomyolysis (ER) are discussed in detail, emphasizing the full clinical spectrum from physiological elevations of serum creatine kinase after exertion to life-threatening rhabdomyolysis with acute kidney injury and associated systemic complications. Laboratory markers used to diagnose both ER and rhabdomyolysis are very sensitive, but not very specific, and imperfectly distinguish "subclinical" or asymptomatic from severe, life-threatening illness. However, genetic factors, both recognized and yet to be discovered, likely influence this diverse clinical spectrum of disease and response to exercise. Genetic mutations causative for McArdle disease, carnitine palmitoyl transferase deficiency 2, myoadenylate deaminase deficiency, and malignant hyperthermia have all been associated with ER. Polymorphic variations in the myosin light chain kinase, α-actin 3, creatine kinase-muscle isoform, angiotensin I-converting enzyme, heat shock protein, and interleukin-6 genes have also been associated with either ER or exercise-induced serum creatine kinase elevations typical of ER. The prognosis for ER is significantly better than that for other etiologies of rhabdomyolysis, but the risk of recurrence after an initial episode is unknown. Guidelines for management are provided.

The effects of daily weather variables on psychosis admissions to psychiatric hospitals

NASA Astrophysics Data System (ADS)

McWilliams, Stephen; Kinsella, Anthony; O'Callaghan, Eadbhard

2013-07-01

Several studies have noted seasonal variations in admission rates of patients with psychotic illnesses. However, the changeable daily meteorological patterns within seasons have never been examined in any great depth in the context of admission rates. A handful of small studies have posed interesting questions regarding a potential link between psychiatric admission rates and meteorological variables such as environmental temperature (especially heat waves) and sunshine. In this study, we used simple non-parametric testing and more complex ARIMA and time-series regression analysis to examine whether daily meteorological patterns (wind speed and direction, barometric pressure, rainfall, sunshine, sunlight and temperature) exert an influence on admission rates for psychotic disorders across 12 regions in Ireland. Although there were some weak but interesting trends for temperature, barometric pressure and sunshine, the meteorological patterns ultimately did not exert a clinically significant influence over admissions for psychosis. Further analysis is needed.

Heat Illness

MedlinePlus

... dangerous levels and you can develop a heat illness. Most heat illnesses happen when you stay out ... in high heat can also lead to heat illness. Older adults, young children, and those who are ...

The induction and decay of heat acclimatisation in trained athletes.

PubMed

Armstrong, L E; Maresh, C M

1991-11-01

Heat acclimatisation/acclimation involves a complex of adaptations which includes decreased heart rate, rectal temperature, perceived exertion as well as increased plasma volume and sweat rate. These adaptations serve to reduce physiological strain, improve an athlete's ability to exercise in a hot environment, and reduce the incidence of some forms of heat illness. Few differences exist in the ability of men and women to acclimatise to heat. Typically, older runners do not perform in the heat as well as younger runners, but physical training can negate differences between these groups. Hormonal adaptations (e.g. aldosterone, vasopressin) during heat acclimatisation encourage fluid-electrolyte retention and cardiovascular stability. Athletes with high maximal aerobic power (VO2max) acclimatise to heat faster (and lose adaptations slower when they are inactive in a cool environment) than athletes with low VO2max values. Physical training in a cool environment improves physiological responses to exercise at high ambient temperatures. In attempting to optimise heat acclimatisation, athletes should maintain fluid-electrolyte balance, exercise at intensities greater than 50% VO2max for 10 to 14 days, and avoid factors (e.g. sleep loss, infectious disease) which are known to reduce heat tolerance. Once acclimatisation has been achieved, inactivity results in a decay of favourable adaptations, after only a few days or weeks.

Exertional Heat-Related Illnesses at the Grand Canyon National Park, 2004–2009

PubMed Central

Noe, Rebecca S.; Choudhary, Ekta; Cheng-Dobson, Jennifer; Wolkin, Amy F.; Newman, Sara B.

2016-01-01

Background The Grand Canyon National Park has approximately 4 million visitors between April and September each year. During this period, outdoor activity such as hiking is potentially hazardous owing to extreme heat, limited shade, and steep, long ascents. Given the high visitation and the public health interest in the effects of extreme heat, this study calculated morbidity rates and described heat-related illness (HRI) among visitors. Methods We conducted a retrospective cross-sectional study from April 1 through September 30, during 2004–2009. From a review of Ranger Emergency Medical Services (EMS) incident report files, we extracted information on those that met the case definition of greater than 1 hour of outdoor heat exposure with an HRI assessment or diagnosis, HRI self-report, or signs or symptoms of HRI without another etiology noted. Visitor and temperature data were obtained from respective official sources. Results Grand Canyon EMS responded to 474 nonfatal and 6 fatal HRI cases, with the majority (84%) being US residents, 29% from Western states. Of the nonfatal cases, 51% were women, the median age was 43 years (range, 11–83 years), and 18% reported a cardiovascular condition. Clinical HRI assessments included dehydration (25%), heat exhaustion (23%), and suspected hyponatremia (19%). Almost all (90%) were hiking; 40% required helicopter evacuation. The highest HRI rates were seen in May. Conclusions HRI remains a public health concern at the Grand Canyon. High-risk evacuations and life-threatening conditions were found. Majority were hikers, middle-aged adults, and US residents. These findings support the park’s hiker HRI prevention efforts and use of park EMS data to measure HRI. PMID:24119571

Gastrointestinal temperature trends in football linemen during physical exertion under heat stress.

PubMed

Coris, Eric E; Mehra, Shabnam; Walz, Stephen M; Duncanson, Robert; Jennings, Jason; Nugent, Dylan; Zwygart, Kira; Pescasio, Michele

2009-06-01

Exertional heat stroke is the third leading cause of death in US athletes. Elevations in core temperature in the digestive tract (TGI) have correlated with core temperature and are possible indicators of those at increased risk of heat stroke. The primary objective was to compare a.m. vs. p.m. TGI variation in collegiate football linemen during intense "two-a-day" preseason practice. A secondary objective was to compare longitudinal TGI in offensive and defensive linemen. Cross-sectional observational study. Division I Intercollegiate Athletics Football Program. TGI was monitored during consecutive preseason sessions. TGI, heat illness, weight changes, environmental stress, and subjective symptoms. Mean TGI were 37.8°C and 38.3°C during a.m. and p.m. practices, respectively. The a.m. practices revealed higher TGI gain (1.8°C) compared to p.m. (1.4°C). The p.m. practices had higher maximum TGI than a.m. practices (39.1°C versus 38.8, P=0.0001). Mean time to maximum temperature (Tmax) was 1 hr and 30 min for a.m. and 1 hr and 22 min for p.m. practices. Offensive linemen trended toward higher mean TGI than defensive players (38.0°C vs. 36.7°C, P = 0.069). The rate of rise in TGI was significantly greater in a.m. practices. A decrease in rate of TGI rise was seen from the first to last a.m. practices of the week (P = 0.004). Significant TGI elevations in asymptomatic athletes are common in extreme heat during football practice. Intense a.m. practices in full gear result in higher net temperature gain and rate of temperature gain than p.m. practices. Offensive linemen trended toward higher TGI than defensive linemen. As players acclimatized, a decrease in the rate of TGI increase was appreciable, particularly in a.m. practices. Appreciating cumulative heat stress and variations in heat stress related to scheduling of practice is critical.

Heat-Related Illnesses

MedlinePlus

... Share this! EmergencyCareForYou » Emergency 101 » Heat-Related Illnesses Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

Risk and preventive factors for heat illness in radiation decontamination workers after the Fukushima Daiichi Nuclear Power Plant accident.

PubMed

Kakamu, Takeyasu; Hidaka, Tomoo; Hayakawa, Takehito; Kumagai, Tomohiro; Jinnouchi, Takanobu; Tsuji, Masayoshi; Nakano, Shinichi; Koyama, Kikuo; Fukushima, Tetsuhito

2015-01-01

The aim of this study was to reveal factors related to heat illness in radiation decontamination workers and determine effective preventive measures. A self-administered questionnaire was sent to 1,505 radiation decontamination workers. The questionnaire included age, sex, duration of decontamination work, previous occupation, education provided by employers regarding heat illness, preventive action against heat illness, and subjective symptoms of heat illness during work. We included 528 men, who replied and answered all questions, in the statistical analysis. Subjective symptoms of heat illness were categorized as "no symptoms", "Grade I" and "Grade II" according to severity. A multiple linear regression model was used to determine the factors associated with the severity of heat illness. The mean age of the subjects was 47.6 years old (standard deviation: 13.4). Of the 528 workers, 316 (59.8%) experienced heat illness symptoms (213 at Grade I and 103 at Grade II). The results of the stepwise selection revealed that age, outdoor manual labor, adequate sleep, use of a cool vest, and salt intake were selected as preventive factors, whereas living in a company dormitory or temporary housing, wearing light clothing, and consuming breakfast were selected as risk factors for heat illness. Both working conditions and living environment are associated with heat illness in radiation decontamination workers. Type of housing and sleep are also strongly related to heat illness during work. Employers should consider not only the working conditions of the employee but also the employee's daily living conditions, in order to prevent heat illness.

Interactions of Gut Microbiota, Endotoxemia, Immune Function, and Diet in Exertional Heatstroke

PubMed Central

Lee, Elaine C.; Armstrong, Elizabeth M.

2018-01-01

Exertional heatstroke (EHS) is a medical emergency that cannot be predicted, requires immediate whole-body cooling to reduce elevated internal body temperature, and is influenced by numerous host and environmental factors. Widely accepted predisposing factors (PDF) include prolonged or intense exercise, lack of heat acclimatization, sleep deprivation, dehydration, diet, alcohol abuse, drug use, chronic inflammation, febrile illness, older age, and nonsteroidal anti-inflammatory drug use. The present review links these factors to the human intestinal microbiota (IM) and diet, which previously have not been appreciated as PDF. This review also describes plausible mechanisms by which these PDF lead to EHS: endotoxemia resulting from elevated plasma lipopolysaccharide (i.e., a structural component of the outer membrane of Gram-negative bacteria) and tissue injury from oxygen free radicals. We propose that recognizing the lifestyle and host factors which are influenced by intestine-microbial interactions, and modifying habitual dietary patterns to alter the IM ecosystem, will encourage efficient immune function, optimize the intestinal epithelial barrier, and reduce EHS morbidity and mortality. PMID:29850597

Heat emergencies

MedlinePlus

Heatstroke; Heat illness ... who is in good shape can suffer heat illness if warning signs are ignored. The following make ... Heat cramps are the first stage of heat illness. If these symptoms are not treated, it can ...

Development of a perceptual hyperthermia index to evaluate heat strain during treadmill exercise.

PubMed

Gallagher, Michael; Robertson, Robert J; Goss, Fredric L; Nagle-Stilley, Elizabeth F; Schafer, Mark A; Suyama, Joe; Hostler, David

2012-06-01

Fire suppression and rescue is a physiologically demanding occupation due to extreme external heat as well as the physical and thermal burden of the protective garments. These conditions challenge body temperature homeostasis and results in heat stress. Accurate field assessment of core temperature is complex and unreliable. The present investigation developed a perceptually based hyperthermia metric to measure physiologic exertional heat strain during treadmill exercise. Sixty-five (28.9 ± 6.8 years) female (n = 11) and male (n = 54) firefighters and non-firefighting volunteers participated in four related exertional heat stress investigations performing treadmill exercise in a heated room while wearing thermal protective clothing. Body core temperature, perceived exertion, and thermal sensation were assessed at baseline, 20-mins exercise, and at termination. Perceived exertion increased from baseline (0.24 ± 0.42) to termination (7.43 ± 1.86). Thermal sensation increased from baseline (1.78 ± 0.77) to termination (4.50 ± 0.68). Perceived exertion and thermal sensation were measured concurrently with body core temperature to develop a two-dimensional graphical representation of three exertional heat strain zones representative of a range of mean body core temperature responses such that low risk (green) incorporated 36.0-37.4°C, moderate risk (yellow) incorporated 37.5-37.9°C, and high risk (red) incorporated 38.0 to greater than 40.5°C. The perceptual hyperthermia index (PHI) may provide a quick and easy momentary assessment of the level of risk for exertional heat stress for firefighters engaged in fire suppression that may be beneficial in high-risk environments that threaten the lives of firefighters.

A Critical Review of OSHA Heat Enforcement Cases: Lessons Learned.

PubMed

Arbury, Sheila; Lindsley, Matthew; Hodgson, Michael

2016-04-01

The aim of the study was to review the Occupational Safety and Health Administration's (OSHA) 2012 to 2013 heat enforcement cases, using identified essential elements of heat illness prevention to evaluate employers' programs and make recommendations to better protect workers from heat illness. (1) Identify essential elements of heat illness prevention; (2) develop data collection tool; and (3) analyze OSHA 2012 to 2013 heat enforcement cases. OSHA's database contains 84 heat enforcement cases in 2012 to 2013. Employer heat illness prevention programs were lacking in essential elements such as providing water and shade; adjusting the work/rest proportion to allow for workload and effective temperature; and acclimatizing and training workers. In this set of investigations, most employers failed to implement common elements of illness prevention programs. Over 80% clearly did not rely on national standard approaches to heat illness prevention.

Physiological tolerance to uncompensated heat stress in soldiers: effects of various types of body cooling systems.

PubMed

Jovanović, Dalibor; Karkalić, Radovan; Zeba, Snjezana; Pavlović, Miroslav; Radaković, Sonja S

2014-03-01

In military services, emergency situations when soldiers are exposed to a combination of nuclear, biological and chemical (NBC) contamination combined with heat stress, are frequent and complex. In these specific conditions, usage of personal body cooling systems may be effective in reducing heat stress. The present study was conducted in order to evaluate the efficiency of four various types of contemporary personal body cooling systems based on the "Phase Change Material" (PCM), and its effects on soldiers' subjective comfort and physiological performance during exertional heat stress in hot environments. Ten male soldiers were voluntarily subjected to exertional heat stress tests (EHSTs) consisted of walking on a treadmill (5.5 km/h) in hot conditions (40 degreesC) in climatic chamber, wearing NBC isolating impermeable protective suits. One of the tests was performed without any additional cooling solution (NOCOOL), and four tests were performed while using different types of cooling systems: three in a form of vests and one as underwear. Physiological strain was determined by the mean skin temperature (Tsk), tympanic temperature (Tty), and heart rate values (HR), while sweat rates (SwR) indicated changes in hydration status. In all the cases EHST induced physiological response manifested through increasing Tty, HR and SwR. Compared to NOCOOL tests, when using cooling vests, Tty and Tsk were significantly lower (on 35th min, for 0.44 +/- 0.03 and 0.49 +/- 0.05 degrees C, respectively; p < 0.05), as well as the average SwR (0.17 +/- 0.03 L/m2/h). When using underwear, the values of given parameters were not significantly different compared to NOCOOL tests. Using a body cooling system based on PCM in the form of vest under NBC protective clothes during physical activity in hot conditions, reduces sweating and alleviates heat stress manifested by increased core and skin temperatures and heart rate values. These effects directly improve heat tolerance, hydration state, decrease in the risk of heat illness, and extends the duration of soldiers' exposure to extreme conditions.

Heat illnesses: a hot topic in the setting of global climate change.

PubMed

Sankoff, Jeffrey

2015-01-01

Heat illnesses affect a large number of people every year and are becoming an increasing cause of pathology as climate change results in increasing global temperatures. This article will review the physiological responses to heat, as well as the pathophysiological processes that result in heat illnesses. The emphasis will be on providing general practitioners (GPs) with an understanding of how to prevent heat illness in their patients and how to predict who is most at risk. Heat illnesses may be thought of as minor or major illnesses, any of which may present to the GP. Consideration must be given to identifying those who need more critical intervention and on when to transfer for higher-level of care.

Exertional heat illness incidence and on-site medical team preparedness in warm weather

NASA Astrophysics Data System (ADS)

Hosokawa, Yuri; Adams, William M.; Belval, Luke N.; Davis, Robert J.; Huggins, Robert A.; Jardine, John F.; Katch, Rachel K.; Stearns, Rebecca L.; Casa, Douglas J.

2018-03-01

To investigate the influence of estimated wet bulb globe temperature (WBGT) and the International Institute of Race Medicine (IIRM) activity modification guidelines on the incidence of exertional heat stroke (EHS) and heat exhaustion (HEx) and the ability of an on-site medical team to treat those afflicted. Medical records of EHS and HEx patients over a 17-year period from the New Balance Falmouth Road Race were examined. Climatologic data from nearby weather stations were obtained to calculate WBGT with the Australian Bureau of Meteorology (WBGTA) and Liljegren (WBGTL) models. Incidence rate (IR) of EHS, HEx, and combined total of EHS and HEx (COM) were calculated, and linear regression analyses were performed to assess the relationship between IR and WBGTA or WBGTL. One-way ANOVA was performed to compare differences in EHS, HEx, and COM incidence to four alert levels in the IIRM guidelines. Incidence of EHS, HEx, and COM was 2.12, 0.98, and 3.10 cases per 1000 finishers. WBGTA explained 48, 4, and 46% of the variance in EHS, HEx, and COM IR; WBGTL explained 63, 13, and 69% of the variance in EHS, HEx, and COM IR. Main effect of WBGTA and WBGTL on the alert levels were observed in EHS and COM IR (p < 0.05). The cumulative number of EHS patients treated did not exceed the number of cold water immersion tubs available to treat them. EHS IR increased as WBGT and IIRM alert level increased, indicating the need for appropriate risk mitigation strategies and on-site medical treatment.

Exertional heat illness incidence and on-site medical team preparedness in warm weather.

PubMed

Hosokawa, Yuri; Adams, William M; Belval, Luke N; Davis, Robert J; Huggins, Robert A; Jardine, John F; Katch, Rachel K; Stearns, Rebecca L; Casa, Douglas J

2018-03-29

To investigate the influence of estimated wet bulb globe temperature (WBGT) and the International Institute of Race Medicine (IIRM) activity modification guidelines on the incidence of exertional heat stroke (EHS) and heat exhaustion (HEx) and the ability of an on-site medical team to treat those afflicted. Medical records of EHS and HEx patients over a 17-year period from the New Balance Falmouth Road Race were examined. Climatologic data from nearby weather stations were obtained to calculate WBGT with the Australian Bureau of Meteorology (WBGT A ) and Liljegren (WBGT L ) models. Incidence rate (IR) of EHS, HEx, and combined total of EHS and HEx (COM) were calculated, and linear regression analyses were performed to assess the relationship between IR and WBGT A or WBGT L . One-way ANOVA was performed to compare differences in EHS, HEx, and COM incidence to four alert levels in the IIRM guidelines. Incidence of EHS, HEx, and COM was 2.12, 0.98, and 3.10 cases per 1000 finishers. WBGT A explained 48, 4, and 46% of the variance in EHS, HEx, and COM IR; WBGT L explained 63, 13, and 69% of the variance in EHS, HEx, and COM IR. Main effect of WBGT A and WBGT L on the alert levels were observed in EHS and COM IR (p < 0.05). The cumulative number of EHS patients treated did not exceed the number of cold water immersion tubs available to treat them. EHS IR increased as WBGT and IIRM alert level increased, indicating the need for appropriate risk mitigation strategies and on-site medical treatment.

Increased risk of hospital admission for dehydration or heat-related illness after initiation of medicines: a sequence symmetry analysis.

PubMed

Kalisch Ellett, L M; Pratt, N L; Le Blanc, V T; Westaway, K; Roughead, E E

2016-10-01

Although several studies have identified factors which increase the risk of heat-related illness, few have assessed the contribution of medicines. To address this knowledge gap, our study aimed to assess the risk of hospital admission for dehydration or other heat-related illness following initiation of medicines. We conducted a retrospective analysis using prescription event symmetry analysis (PESA) of 6700 veterans with incident hospital admission for dehydration or heat-related illness (ICD-10-AM codes E86, X30, T67), between 1 January 2001 and 30 June 2013. The main outcome measure was first ever hospital admission for dehydration or heat-related illness following initiation of commonly used medicines. A significantly higher risk of incident hospital admission for dehydration or heat-related illness was observed following initiation of anticoagulants, cardiovascular medicines, NSAIDs, antipsychotics, antidepressants and anticholinergic agents. The risk of hospital admission for dehydration or heat-related illness ranged from 1·17 (SSRIs) to 2·79 (ACEI plus diuretic combination product). No significant association was observed between initiation of anticonvulsants, anti-Parkinson's agents, hypnotics, anxiolytics or antihistamines and hospital admission for dehydration or heat-related illness. Many commonly used medicines were found to be associated with increased risk of hospitalization for dehydration or heat-related illness. Initiation of ACE inhibitors in combination with diuretics had the highest risk. Prescribers and patients should be aware of the potential for medicines to be associated with increased risk of dehydration and heat-related illness. © 2016 John Wiley & Sons Ltd.

Treatment and prevention of pediatric heat-related illnesses at mass gatherings and special events.

PubMed

Bernardo, Lisa Marie; Crane, Patricia A; Veenema, Tener Goodwin

2006-01-01

Pediatric heat-related illnesses are likely to occur during mass gatherings and special events. Because critical care nurses may be called upon to provide care during such events, education in the recognition, treatment, and prevention of these illnesses is essential. This article describes the pathophysiology of heat-related illnesses and their recognition and treatment at mass gatherings and special events. Interventions to prevent heat-related illnesses at these events are discussed.

Work-attributed illness arising from excess heat exposure in Ontario, 2004-2010.

PubMed

Fortune, Melanie K; Mustard, Cameron A; Etches, Jacob J C; Chambers, Andrea G

2013-09-12

To describe the incidence of occupational heat illness in Ontario. Heat illness events were identified in two population-based data sources: work-related emergency department (ED) records and lost time claims for the period 2004-2010 in Ontario, Canada. Incidence rates were calculated using denominator estimates from national labour market surveys and estimates were adjusted for workers' compensation insurance coverage. Proportional morbidity ratios were estimated for industry, occupation and tenure of employment. There were 785 heat illness events identified in the ED encounter records (incidence rate 1.6 per 1,000,000 full-time equivalent (FTE) months) and 612 heat illness events identified in the lost time claim records (incidence rate 1.7 per 1,000,000 FTE months) in the seven-year observation period with peak incidence observed in the summer months. The risk of heat illness was elevated for men, young workers, manual workers and those with shorter employment tenure. A higher proportion of lost time claims attributed to heat illness were observed in the government services, agriculture and construction sectors relative to all lost time claims. Occupational heat illnesses are experienced in Ontario's population and are observed in ED records and lost time claims. The variation of heat illness incidence observed with worker and industry characteristics, and over time, can inform prevention efforts by occupational health services in Ontario.

Case ascertainment of heat illness in the British Army: evidence of under-reporting from analysis of Medical and Command notifications, 2009-2013.

PubMed

Stacey, Michael J; Brett, S; Woods, D; Jackson, S; Ross, D

2016-12-01

Heat illness in the Armed Forces is considered preventable. The UK military relies upon dual Command and Medical reporting for case ascertainment, investigation of serious incidents and improvement of preventive practices and policy. This process could be vulnerable to under-reporting. To establish whether heat illness in the British Army has been under-reported, by reviewing concordance of reporting to the Army Incident Notification Cell (AINC) and the Army Health Unit (AHU) and to characterise the burden of heat illness reported by these means. Analysis of anonymised reporting databases held by the AHU and AINC, for the period 2009-2013. 565 unique cases of heat illness were identified. Annual concordance of reporting ranged from 9.6% to 16.5%. The overall rate was 13.3%. July was the month with the greatest number of heat illness reports (24.4% of total reporting) and the highest concordance rate (30%). Reports of heat illness from the UK (n=343) exceeded overseas notifications (n=221) and showed better concordance (17.1% vs 12.8%). The annual rate of reported heat illness varied widely, being greater in full-time than reservist personnel (87 vs 23 per100 000) and highest in full-time untrained personnel (223 per100 000). The risk of heat illness was global, year-round and showed dynamic local variation. Failure to dual-report casualties impaired case ascertainment of heat illness across Command and Medical chains. Current preventive guidance, as applied in training and on operations, should be critically evaluated to ensure that risk of heat illness is reduced as low as possible. Clear procedures for casualty notification and surveillance are required in support of this and should incorporate communication within and between the two reporting chains. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Case ascertainment of heat illness in the British Army: evidence of under-reporting from analysis of Medical and Command notifications, 2009–2013

PubMed Central

Stacey, Michael J; Brett, S; Woods, D; Jackson, S; Ross, D

2016-01-01

Background Heat illness in the Armed Forces is considered preventable. The UK military relies upon dual Command and Medical reporting for case ascertainment, investigation of serious incidents and improvement of preventive practices and policy. This process could be vulnerable to under-reporting. Objectives To establish whether heat illness in the British Army has been under-reported, by reviewing concordance of reporting to the Army Incident Notification Cell (AINC) and the Army Health Unit (AHU) and to characterise the burden of heat illness reported by these means. Methods Analysis of anonymised reporting databases held by the AHU and AINC, for the period 2009–2013. Results 565 unique cases of heat illness were identified. Annual concordance of reporting ranged from 9.6% to 16.5%. The overall rate was 13.3%. July was the month with the greatest number of heat illness reports (24.4% of total reporting) and the highest concordance rate (30%). Reports of heat illness from the UK (n=343) exceeded overseas notifications (n=221) and showed better concordance (17.1% vs 12.8%). The annual rate of reported heat illness varied widely, being greater in full-time than reservist personnel (87 vs 23 per100 000) and highest in full-time untrained personnel (223 per100 000). Conclusions The risk of heat illness was global, year-round and showed dynamic local variation. Failure to dual-report casualties impaired case ascertainment of heat illness across Command and Medical chains. Current preventive guidance, as applied in training and on operations, should be critically evaluated to ensure that risk of heat illness is reduced as low as possible. Clear procedures for casualty notification and surveillance are required in support of this and should incorporate communication within and between the two reporting chains. PMID:25717054

Heat-Related Illnesses

MedlinePlus Videos and Cool Tools

... for signs of heat stroke or exhaustion. Heat Stroke and Exhaustion Symptoms of early heat exhaustion symptoms ... heavy sweating; nausea; and giddiness. Symptoms of heat stroke (late stage of heat illness) include flushed, hot, ...

Estimating the burden of heat illness in England during the 2013 summer heatwave using syndromic surveillance

PubMed Central

Smith, Sue; Elliot, Alex J; Hajat, Shakoor; Bone, Angie; Smith, Gillian E; Kovats, Sari

2016-01-01

Background The burden of heat illness on health systems is not well described in the UK. Although the UK generally experiences mild summers, the frequency and intensity of hot weather is likely to increase due to climate change, particularly in Southern England. We investigated the impact of the moderate heatwave in 2013 on primary care and emergency department (ED) visits using syndromic surveillance data in England. Methods General practitioner in hours (GPIH), GP out of hours (GPOOH) and ED syndromic surveillance systems were used to monitor the health impact of heat/sun stroke symptoms (heat illness). Data were stratified by age group and compared between heatwave and non-heatwave years. Incidence rate ratios were calculated for GPIH heat illness consultations. Results GP consultations and ED attendances for heat illness increased during the heatwave period; GPIH consultations increased across all age groups, but the highest rates were in school children and those aged ≥75 years, with the latter persisting beyond the end of the heatwave. Extrapolating to the English population, we estimated that the number of GPIH consultations for heat illness during the whole summer (May to September) 2013 was 1166 (95% CI 1064 to 1268). This was double the rate observed during non-heatwave years. Conclusions These findings support the monitoring of heat illness (symptoms of heat/sun stroke) as part of the Heatwave Plan for England, but also suggest that specifically monitoring heat illness in children, especially those of school age, would provide additional early warning of, and situation awareness during heatwaves. PMID:26873949

On the heating mechanism of magnetic flux loops in the solar atmosphere

NASA Technical Reports Server (NTRS)

Song, M. T.; Wu, S. T.

1984-01-01

An investigation is conducted of physical heating mechanisms due to the ponderomotive forces exerted by turbulent waves along the solar atmosphere's curved magnetic flux loops. Results indicate that the temperature difference between the inside and outside of the flux loop can be classified into three parts, two of which represent the cooling or heating effect exerted by the ponderomotive force, while the third is the heating effect due to turbulent energy conversion from the localized plasma. This heating mechanism is used to illustrate solar atmospheric heating by means of an example that leads to the formulation of plages.

Current knowledge, attitudes, and practices of certified athletic trainers regarding recognition and treatment of exertional heat stroke.

PubMed

Mazerolle, Stephanie M; Scruggs, Ian C; Casa, Douglas J; Burton, Laura J; McDermott, Brendon P; Armstrong, Lawrence E; Maresh, Carl M

2010-01-01

Previous research has indicated that despite awareness of the current literature on the recommended prevention and care of exertional heat stroke (EHS), certified athletic trainers (ATs) acknowledge failure to follow those recommendations. To investigate the current knowledge, attitudes, and practices of ATs regarding the recognition and treatment of EHS. Cross-sectional study. Online survey. We obtained a random sample of e-mail addresses for 1000 high school and collegiate ATs and contacted these individuals with invitations to participate. A total of 498 usable responses were received, for a 25% response rate. The survey instrument evaluated ATs' knowledge and actual practice regarding EHS and included 29 closed-ended Likert scale questions (1 = strongly disagree, 7 = strongly agree), 2 closed-ended questions rated on a Likert scale (1 = lowest value, 9 = greatest value), 8 open-ended questions, and 7 demographic questions. We focused on the open-ended and demographic questions. Although most ATs (77.1%) have read the current National Athletic Trainers' Association position statement on heat illness, only 18.6% used rectal thermometers to assess core body temperature to recognize EHS, and 49.7% used cold-water immersion to treat EHS. Athletic trainers perceived rectal thermometers as the most valid temperature assessment device when compared with other assessment devices (P

Extreme Heat: A Prevention Guide to Promote Your Personal Health and Safety

MedlinePlus

... in your office, school, or home. Related Links Climate Change- Extreme Heat Heat Stress Illness Search Heat Stress Illness Data Temperature Extremes- Climate and Health Language: English (US) Español (Spanish) File ...

78 FR 78962 - Criteria for a Recommended Standard; Occupational Exposure to Heat and Hot Environments; Draft...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-27

.... Heat stress can result in heat-related illnesses such as heat stroke, heat exhaustion, heat cramps, or... related materials, visit http://www.regulations.gov and enter CDC-2013-0025 in the search field and click... hydration that should be considered? (4) Are there any additional risk factors for heat-related illnesses...

Heat acclimation responses of an ultra-endurance running group preparing for hot desert-based competition.

PubMed

Costa, Ricardo J S; Crockford, Michael J; Moore, Jonathan P; Walsh, Neil P

2014-01-01

Heat acclimation induces adaptations that improve exercise tolerance in hot conditions. Here we report novel findings into the effects of ultra-marathon specific exercise load in increasing hot ambient conditions on indices of heat acclimation. Six male ultra-endurance runners completed a standard pre-acclimation protocol at 20°C ambient temperature (T amb), followed by a heat acclimation protocol consisting of six 2 h running exercise-heat exposures (EH) at 60% VO2max on a motorised treadmill in an environmental chamber. Three EH were performed at 30°C T amb, followed by another three EH at 35°C T amb. EH were separated by 48 h within T amb and 72 h between T amb. Nude body mass (NBM), blood and urine samples were collected pre-exercise; while NBM and urine were collected post-exercise. Rectal temperature (T re), heart rate (HR), thermal comfort rating (TCR) and rating of perceived exertion were measured pre-exercise and monitored every 5 min during exercise. Water was provided ad libitum during exercise. Data were analysed using a repeated measures and one-way analysis of variance (ANOVA), with post hoc Tukey's HSD. Significance was accepted as P< 0.05. Overall mean T re was significantly lower during 30°C EH3 and 35°C EH3 compared with their respective EH1 (-0.20 and-0.23°C, respectively; P<0.05). Similarly, overall mean HR was significantly lower during 30°C EH3 and 35°C EH3 compared with their respective EH1 (8 and 7 bpm respectively; P<0.05). A significant decrease in overall mean TCR was observed during 35°C EH3, compared with 35°C EH1 (P< 0.05). Significant increases in resting pre-exercise plasma volume (estimated from Hb and Hct) were observed by 30°C EH3 (7.9%; P< 0.05). Thereafter, plasma volume remained above baseline throughout the experimental protocol. Two EH of 2 h at 60% VO2max at 30°C T amb was sufficient to initiate heat acclimation in all ultra-endurance runners. Further, heat acclimation responses occurred with increasing EH to 35°C T amb. Preventing exertional heat illnesses and optimising performance outcomes in ultra-endurance runners may occur with exposure to at least 2 h of exercise-heat stress on at least two occasions in the days leading up to multi-stage ultra-marathon competition in the heat.

Heat illness and death among workers - United States, 2012-2013.

PubMed

Arbury, Sheila; Jacklitsch, Brenda; Farquah, Opeyemi; Hodgson, Michael; Lamson, Glenn; Martin, Heather; Profitt, Audrey

2014-08-08

Exposure to heat and hot environments puts workers at risk for heat stress, which can result in heat illnesses and death. This report describes findings from a review of 2012‒2013 Occupational Safety and Health Administration (OSHA) federal enforcement cases (i.e., inspections) resulting in citations under paragraph 5(a)(1), the "general duty clause" of the Occupational Safety and Health Act of 1970. That clause requires that each employer "furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees". Because OSHA has not issued a heat standard, it must use 5(a)(1) citations in cases of heat illness or death to enforce employers' obligations to provide a safe and healthy workplace. During the 2-year period reviewed, 20 cases of heat illness or death were cited for federal enforcement under paragraph 5(a)(1) among 18 private employers and two federal agencies. In 13 cases, a worker died from heat exposure, and in seven cases, two or more employees experienced symptoms of heat illness. Most of the affected employees worked outdoors, and all performed heavy or moderate work, as defined by the American Conference of Governmental Industrial Hygienists. Nine of the deaths occurred in the first 3 days of working on the job, four of them occurring on the worker's first day. Heat illness prevention programs at these workplaces were found to be incomplete or absent, and no provision was made for the acclimatization of new workers. Acclimatization is the result of beneficial physiologic adaptations (e.g., increased sweating efficiency and stabilization of circulation) that occur after gradually increased exposure to heat or a hot environment. Whenever a potential exists for workers to be exposed to heat or hot environments, employers should implement heat illness prevention programs (including acclimatization requirements) at their workplaces.

Heat stress disorders and headache: a case of new daily persistent headache secondary to heat stroke.

PubMed

Di Lorenzo, C; Ambrosini, A; Coppola, G; Pierelli, F

2009-01-01

Headache is considered as a common symptom of heat stress disorders (HSD), but no forms of secondary headache from heat exposure are reported in the International Classification of Headache Disorders-2 Edition (ICHD-II). Heat-stroke (HS) is the HSD most severe condition, it may be divided into two forms: classic (due to a long period environmental heat exposure) and exertional (a severe condition caused by strenuous physical exercises in heat environmental conditions). Here we report the case of a patient who developed a headache clinical picture fulfilling the diagnostic criteria for new daily persistent headache (NDPH), after an exertional HS, and discuss about possible pathophysiological mechanisms and classification aspects of headache induced by heat conditions.

Heat stress disorders and headache: a case of new daily persistent headache secondary to heat stroke

PubMed Central

Di Lorenzo, C; Ambrosini, A; Coppola, G; Pierelli, F

2009-01-01

Headache is considered as a common symptom of heat stress disorders (HSD), but no forms of secondary headache from heat exposure are reported in the International Classification of Headache Disorders-2 Edition (ICHD-II). Heat-stroke (HS) is the HSD most severe condition, it may be divided into two forms: classic (due to a long period environmental heat exposure) and exertional (a severe condition caused by strenuous physical exercises in heat environmental conditions). Here we report the case of a patient who developed a headache clinical picture fulfilling the diagnostic criteria for new daily persistent headache (NDPH), after an exertional HS, and discuss about possible pathophysiological mechanisms and classification aspects of headache induced by heat conditions. PMID:21686677

Promoting Best Practices regarding Exertional Heat Stroke: A Perspective from the Team Physician

ERIC Educational Resources Information Center

Mazerolle, Stephanie M.; Pagnotta, Kelly D.; McDowell, Lindsey; Casa, Douglas J.; Armstrong, Lawrence

2012-01-01

Context: Knowing the team physician's perspective regarding the use of evidence-based practice (EBP) for treatment of exertional heat stroke (EHS) may help increase the number of athletic trainers (ATs) implementing best practices and avoiding the use of improper assessment tools and treatment methods. Objective: To ascertain team physicians'…

Professional Preparation regarding the Recognition and Treatment of Exertional Heat Stroke: The Student Perspective

ERIC Educational Resources Information Center

Mazerolle, Stephanie M.; Pagnotta, Kelly D.; Casa, Douglas J.; Armstrong, Lawrence; Maresh, Carl

2011-01-01

Context: Current evidence suggests rectal temperature(T[subscript re] and cold-water immersion (CWI) are the most effective means to diagnose and treat exertional heat stroke (EHS), respectively. Educators, clinicians, and students should be apprised of this evidence to guide their practice. Objective: Investigate what athletic training students…

Effects of a New Cooling Technology on Physical Performance in US Air Force Military Personnel.

PubMed

O'Hara, Reginald; Vojta, Christopher; Henry, Amy; Caldwell, Lydia; Wade, Molly; Swanton, Stacie; Linderman, Jon K; Ordway, Jason

2016-01-01

Heat-related illness is a critical factor for military personnel operating in hyperthermic environments. Heat illness can alter cognitive and physical performance during sustained operations missions. Therefore, the primary purpose of this investigation was to determine the effects of a novel cooling shirt on core body temperature in highly trained US Air Force personnel. Twelve trained (at least 80th percentile for aerobic fitness according to the American College of Sports Medicine, at least 90% on the US Air Force fitness test), male Air Force participants (mean values: age, 25 ± 2.8 years; height, 178 ± 7.9cm; body weight 78 ± 9.6kg; maximal oxygen uptake, 57 ± 1.9mL/kg/ min; and body fat, 10% ± 0.03%) completed this study. Subjects performed a 70-minute weighted treadmill walking test and 10-minute, 22.7kg sandbag shuttle test under two conditions: (1) "loaded" (shirt with cooling inserts) and (2) "unloaded" (shirt with no cooling inserts). Core body temperature, exercise heart rate, capillary blood lactate, and ratings of perceived exertion were recorded. Core body temperature was lower (ρ = .001) during the 70-minute treadmill walking test in the loaded condition. Peak core temperature during the 70-minute walking test was also significantly lower (ρ = .038) in the loaded condition. This lightweight (471g), passive cooling technology offers multiple hours of sustained cooling and reduced core and peak body temperature during a 70-minute, 22.7kg weighted-vest walking test. 2016.

The effects of a heat acclimation protocol in persons with spinal cord injury.

PubMed

Trbovich, Michelle B; Kiratli, Jenny B; Price, Mike J

2016-12-01

Persons without spinal cord injury (SCI) physiologically acclimate between seven to fourteen consecutive days of exercise in the heat. Decreased resting and exercise core temperature, decreased heart rate, increased plasma volume and increased thermal comfort during exercise are changes consistent with heat acclimation. Autonomic dysfunction after SCI impairs heat dissipation through sweating and vasodilation. The purpose of this study is to determine if seven consecutive days of exercise in the heat would result in physiologic changes consistent with heat acclimation in persons with SCI. Ten persons with SCI divided into two groups: tetraplegia (n=5) and paraplegia (n=5) exercised in 35°C using an arm ergometer at 50% W peak for 30min followed by 15min rest. This protocol was repeated over seven consecutive days. Heart rate (HR), skin temperature, aural temperature (T aur ), rate of perceived exertion (RPE), rate of perceived thermal strain (RPTS), and plasma volume (PV) were measured throughout the protocol. There were no significant differences in resting T aur exercise T aur , mean skin temperature, HR, PV, RPE or RPTS over the 7 days for either the tetraplegic or paraplegic group. Participants with SCI did not demonstrate the ability to dissipate heat more efficiently over 7 days of exercise at 35°C. The lack of heat acclimation seen in persons with SCI has implications for the athlete and non-athlete alike. For the SCI athlete, inability to acclimate will impair performance and endurance especially in warm environments, compared to the person without SCI. For the SCI non-athlete, there is a greater risk of heat-related illness in warm environments that can negatively affect participation in outdoor activities and thus quality of life. Published by Elsevier Ltd.

Characteristics of Heat Illness during Hajj: A Cross-Sectional Study

PubMed Central

El-Bakri, Nahid K.; Almowalld, Wedian O.; Turkistani, Zyad A.; Bugis, Bassam H.; Baseif, Eshraq A.; Melbari, Mohamed H.; AlHarbi, Khaled

2018-01-01

Introduction Data regarding the characteristics and outcomes of heat illness are lacking in the literature. The present study aimed to identify the clinical characteristics, morbidity, management, and mortality associated with heat illness among Hajj participants. Methods A cross-sectional study was conducted during the Hajj in 2016 on patients who presented to emergency departments and were diagnosed with heat exhaustion or heatstroke. Data were collected using a structured collection sheet developed based on the literature. Results A total of 267 patients were recruited. Of these, 80 (29%) and 187 (67.75%) were diagnosed with heatstroke and heat exhaustion, with 6.3% and 0.0% mortality, respectively. The mean age of the patients was 54.0 ± 16 years. Diabetes mellitus was the most common comorbidity among both heatstroke and heat exhaustion patients. The majority of patients had hyperthermia and electrolyte imbalance. Most of the heat illness cases were treated per heat illness guidelines. Conclusions Although authorities are working on research and forming interdisciplinary teams to prevent health problems during the Hajj, the mortality rate from heatstroke is high and the majority of the patients had hyperthermia, varied signs and symptoms, elevated creatinine levels, and electrolyte imbalances. PMID:29662887

Heat-related illness in China, summer of 2013

NASA Astrophysics Data System (ADS)

Gu, Shaohua; Huang, Cunrui; Bai, Li; Chu, Cordia; Liu, Qiyong

2016-01-01

Extreme heat events have occurred more frequently in China in recent years, leading to serious impacts on human life and the health care system. To identify the characteristics of individuals with heat-related illnesses in China during the summer of 2013, we collected the data from the Heat-related Illness Surveillance System in Chinese Center for Disease Control and Prevention (China CDC). A total of 5758 cases were reported in the summer of 2013, mostly concentrated in urban areas around the middle and lower reaches of the Yangtze River. We found a difference in age distribution of percentage of deaths from heat-related illness between males and females. Severe cases in males mostly occurred in the age group 45-74 years but in females mostly in the age group over 75. A distributed lag non-linear model had been used to identify population vulnerabilities in Ningbo and Chongqing. The results show that there was a clear positive relationship between maximum temperature and heat-related illness, and the heat effect was nonlinear and could last for 3 days. The elderly and males in the range of 45-64 years old might be the most vulnerable people of heat-related illness in China. We also highlighted some deficiencies of the surveillance system, such that the reported data were not accurate, comprehensive, or timely enough at this stage.

Heat-Related Illnesses

DTIC Science & Technology

1988-04-01

factors, thermometry, and fever versus hyper- thernia. ihe review of heat illnesses includes heat "anps, heat edema, heat syncope, heat exhaustiom...clinical situations. For example, fever , the daily circadian rhythm of temperature variation, and the 0.50 C difference in rectal temperature following...thermometry is state of the art. Fever versus Hyperthermia Elevations of body temperature can occur as a result of several different mechanisms. One

Athletic Trainers' Attitudes and Perceptions Regarding Exertional Heat Stroke before and after an Educational Intervention

ERIC Educational Resources Information Center

Schellhase, Kristen Couper; Plant, Jennifer; Mazerolle, Stephanie M.

2017-01-01

Context: Death from exertional heat stroke (EHS) is preventable when evidence-based guidelines are followed. The assessment of core body temperature using rectal thermometry and the treatment of cold-water immersion for EHS has been established as the standard of care; however, rectal thermometry is still controversial. Athletic trainers (ATs) may…

Preventing Heat-Related Illness or Death of Outdoor Workers

MedlinePlus

... attention to workers who show signs of heat-related illness „ „ Evaluating work practices continually to reduce ex- ertion and environmental heat stress „ „ Monitoring weather reports daily and reschedul- ing jobs ...

Prevention of Organ Injury in Exertional Heat Stroke: Preclinical Evaluation of a New Class of NSAIDs

DTIC Science & Technology

2016-10-01

both sexes ), neurological symptoms and organ injury resembling human EHS. Blood and tissue samples were collected at 0.5 h, 3 h, 24 h 4d,9d and 14d of...associated with adipose tissue. Analyses of metabolic hormones and histology in both sexes suggest transient injury or “stunning” to the pancreas...15. SUBJECT TERMS Sex differences, exertional heat stroke, multi-organ injury, heat stress, metabolic hormones 16. SECURITY CLASSIFICATION OF: U 17

A Case-Crossover Study of Heat Exposure and Injury Risk in Outdoor Agricultural Workers.

PubMed

Spector, June T; Bonauto, David K; Sheppard, Lianne; Busch-Isaksen, Tania; Calkins, Miriam; Adams, Darrin; Lieblich, Max; Fenske, Richard A

2016-01-01

Recent research suggests that heat exposure may increase the risk of traumatic injuries. Published heat-related epidemiological studies have relied upon exposure data from individual weather stations. To evaluate the association between heat exposure and traumatic injuries in outdoor agricultural workers exposed to ambient heat and internal heat generated by physical activity using modeled ambient exposure data. A case-crossover study using time-stratified referent selection among 12,213 outdoor agricultural workers with new Washington State Fund workers' compensation traumatic injury claims between 2000 and 2012 was conducted. Maximum daily Humidex exposures, derived from modeled meteorological data, were assigned to latitudes and longitudes of injury locations on injury and referent dates. Conditional logistic regression was used to estimate odds ratios of injury for a priori daily maximum Humidex categories. The mean of within-stratum (injury day and corresponding referent days) standard deviations of daily maximum Humidex was 4.8. The traumatic injury odds ratio was 1.14 (95% confidence interval 1.06, 1.22), 1.15 (95% confidence interval 1.06, 1.25), and 1.10 (95% confidence interval 1.01, 1.20) for daily maximum Humidex of 25-29, 30-33, and ≥34, respectively, compared to < 25, adjusted for self-reported duration of employment. Stronger associations were observed during cherry harvest duties in the June and July time period, compared to all duties over the entire study period. Agricultural workers laboring in warm conditions are at risk for heat-related traumatic injuries. Combined heat-related illness and injury prevention efforts should be considered in high-risk populations exposed to warm ambient conditions in the setting of physical exertion.

Survey Instrument Validity Part II: Validation of a Survey Instrument Examining Athletic Trainers' Knowledge and Practice Beliefs Regarding Exertional Heat Stroke

ERIC Educational Resources Information Center

Burton, Laura J.; Mazerolle, Stephanie M.

2011-01-01

Objective: The purpose of this article is to discuss the process of developing and validating an instrument to investigate an athletic trainer's attitudes and behaviors regarding the recognition and treatment of exertional heat stroke. Background: Following up from our initial paper, which discussed the process of survey instrument design and…

Heat stress, gastrointestinal permeability and interleukin-6 signaling — Implications for exercise performance and fatigue

PubMed Central

Vargas, Nicole; Marino, Frank

2016-01-01

ABSTRACT Exercise in heat stress exacerbates performance decrements compared to normothermic environments. It has been documented that the performance decrements are associated with reduced efferent drive from the central nervous system (CNS), however, specific factors that contribute to the decrements are not completely understood. During exertional heat stress, blood flow is preferentially distributed away from the intestinal area to supply the muscles and brain with oxygen. Consequently, the gastrointestinal barrier becomes increasingly permeable, resulting in the release of lipopolysaccharides (LPS, endotoxin) into the circulation. LPS leakage stimulates an acute-phase inflammatory response, including the release of interleukin (IL)-6 in response to an increasingly endotoxic environment. If LPS translocation is too great, heat shock, neurological dysfunction, or death may ensue. IL-6 acts initially in a pro-inflammatory manner during endotoxemia, but can attenuate the response through signaling the hypothalamic pituitary adrenal (HPA)-axis. Likewise, IL-6 is believed to be a thermoregulatory sensor in the gut during the febrile response, hence highlighting its role in periphery – to – brain communication. Recently, IL-6 has been implicated in signaling the CNS and influencing perceptions of fatigue and performance during exercise. Therefore, due to the cascade of events that occur during exertional heat stress, it is possible that the release of LPS and exacerbated response of IL-6 contributes to CNS modulation during exertional heat stress. The purpose of this review is to evaluate previous literature and discuss the potential role for IL-6 during exertional heat stress to modulate performance in favor of whole body preservation. PMID:27857954

Heat stress, gastrointestinal permeability and interleukin-6 signaling - Implications for exercise performance and fatigue.

PubMed

Vargas, Nicole; Marino, Frank

2016-01-01

Exercise in heat stress exacerbates performance decrements compared to normothermic environments. It has been documented that the performance decrements are associated with reduced efferent drive from the central nervous system (CNS), however, specific factors that contribute to the decrements are not completely understood. During exertional heat stress, blood flow is preferentially distributed away from the intestinal area to supply the muscles and brain with oxygen. Consequently, the gastrointestinal barrier becomes increasingly permeable, resulting in the release of lipopolysaccharides (LPS, endotoxin) into the circulation. LPS leakage stimulates an acute-phase inflammatory response, including the release of interleukin (IL)-6 in response to an increasingly endotoxic environment. If LPS translocation is too great, heat shock, neurological dysfunction, or death may ensue. IL-6 acts initially in a pro-inflammatory manner during endotoxemia, but can attenuate the response through signaling the hypothalamic pituitary adrenal (HPA)-axis. Likewise, IL-6 is believed to be a thermoregulatory sensor in the gut during the febrile response, hence highlighting its role in periphery - to - brain communication. Recently, IL-6 has been implicated in signaling the CNS and influencing perceptions of fatigue and performance during exercise. Therefore, due to the cascade of events that occur during exertional heat stress, it is possible that the release of LPS and exacerbated response of IL-6 contributes to CNS modulation during exertional heat stress. The purpose of this review is to evaluate previous literature and discuss the potential role for IL-6 during exertional heat stress to modulate performance in favor of whole body preservation.

The effects of acclimatization on blood clotting parameters in exertional heat stress.

PubMed

Vesić, Zoran; Vukasinović-Vesić, Milica; Dincić, Dragan; Surbatović, Maja; Radaković, Sonja S

2013-07-01

Exertional heat stress is a common problem in military services. Considering the coagulation abnormalities are of major importance in development of severe heat stroke, we wanted to examine changes in hemostatic parameters in soldiers during exertional heat stress test as well as the effects of a 10-day passive or active acclimatization in a climatic chamber. A total of 40 male soldiers with high aerobic capacity performed exertional heat stress test (EHST) either in cool [20 degrees C, 16 degrees C wet bulb globe temperature (WBGT)], or hot (40 degrees C, 29 degrees C, (WBGT) environment, unacclimatized (U) or after 10 days of passive (P) or active (A) acclimatization. Physiological strain was measured by tympanic temperatures (Tty) and heart rates (HR). Platelet count (PC), antithrombin III (AT), and prothrombin time (PT) were assessed in blood samples collected before and immediately after the EHST. EHST in hot conditions induced physiological heat stress (increase in Tty and HR), with a significant increase in prothrombin time in the groups U and A. Platelet counts were significantly higher after the EHST compared to the basic levels in all the investigated groups, regardless environmental conditions and acclimatization state. Antithrombin levels were not affected by EHST whatsoever. In the trained soldiers, physiological heat stress caused mild changes in some serum parameters of blood clotting such as prothrombin time, while others such as antithrombin levels were not affected. Platelet counts were increased after EHST in all groups. A 10-day passive or active acclimatization in climatic chamber showed no effect on parameters investigated.

Knowledge and awareness of heat-related morbidity among adult recreational endurance athletes

NASA Astrophysics Data System (ADS)

Shendell, Derek G.; Alexander, Melannie S.; Lorentzson, Lauren; McCarty, Frances A.

2010-07-01

Adults have been increasingly motivated to compete in recreational endurance sports events. Amateurs may lack a complete understanding of recommended strategies for handling heat and humidity, making heat-related illnesses increasingly possible. This is compounded by global climate change and increasing average surface and air temperatures, especially in urban areas of industrialized nations in Europe and North America that have hosted most events to date. We conducted an on-line, secure survey at the 2nd Annual ING Georgia Marathon and Half-Marathon in Atlanta, Georgia, in 2008. We included previously validated questions on participant socio-demographics, training locations, and knowledge and awareness of heat-related illnesses. Participants were aware of heat illnesses, and of heat stroke as a serious form of heat stress. However, the majority, across age and gender, did not understand the potential severity of heat stroke. Furthermore, 1-in-5 participants did not understand the concept of heat stress as a form of heat-related illness, and how heat stress may result from buildup of muscle-generated heat in the body. Adult recreational endurance athletes are another susceptible, vulnerable population sub-group for applied research and public health educational interventions, especially in urban areas of industrialized nations in Europe and North America.

Knowledge and awareness of heat-related morbidity among adult recreational endurance athletes.

PubMed

Shendell, Derek G; Alexander, Melannie S; Lorentzson, Lauren; McCarty, Frances A

2010-07-01

Adults have been increasingly motivated to compete in recreational endurance sports events. Amateurs may lack a complete understanding of recommended strategies for handling heat and humidity, making heat-related illnesses increasingly possible. This is compounded by global climate change and increasing average surface and air temperatures, especially in urban areas of industrialized nations in Europe and North America that have hosted most events to date. We conducted an on-line, secure survey at the 2nd Annual ING Georgia Marathon and Half-Marathon in Atlanta, Georgia, in 2008. We included previously validated questions on participant socio-demographics, training locations, and knowledge and awareness of heat-related illnesses. Participants were aware of heat illnesses, and of heat stroke as a serious form of heat stress. However, the majority, across age and gender, did not understand the potential severity of heat stroke. Furthermore, 1-in-5 participants did not understand the concept of heat stress as a form of heat-related illness, and how heat stress may result from buildup of muscle-generated heat in the body. Adult recreational endurance athletes are another susceptible, vulnerable population sub-group for applied research and public health educational interventions, especially in urban areas of industrialized nations in Europe and North America.

Relationships between maximum temperature and heat-related illness across North Carolina, USA.

PubMed

Sugg, Margaret M; Konrad, Charles E; Fuhrmann, Christopher M

2016-05-01

Heat kills more people than any other weather-related event in the USA, resulting in hundreds of fatalities each year. In North Carolina, heat-related illness accounts for over 2,000 yearly emergency department admissions. In this study, data on emergency department (ED) visits for heat-related illness (HRI) were obtained from the North Carolina Disease Event Tracking and Epidemiologic Collection Tool to identify spatiotemporal relationships between temperature and morbidity across six warm seasons (May-September) from 2007 to 2012. Spatiotemporal relationships are explored across different regions (e.g., coastal plain, rural) and demographics (e.g., gender, age) to determine the differential impact of heat stress on populations. This research reveals that most cases of HRI occur on days with climatologically normal temperatures (e.g., 31 to 35 °C); however, HRI rates increase substantially on days with abnormally high daily maximum temperatures (e.g., 31 to 38 °C). HRI ED visits decreased on days with extreme heat (e.g., greater than 38 °C), suggesting that populations are taking preventative measures during extreme heat and therefore mitigating heat-related illness.

Exercise challenge in Gulf War Illness reveals two subgroups with altered brain structure and function.

PubMed

Rayhan, Rakib U; Stevens, Benson W; Raksit, Megna P; Ripple, Joshua A; Timbol, Christian R; Adewuyi, Oluwatoyin; VanMeter, John W; Baraniuk, James N

2013-01-01

Nearly 30% of the approximately 700,000 military personnel who served in Operation Desert Storm (1990-1991) have developed Gulf War Illness, a condition that presents with symptoms such as cognitive impairment, autonomic dysfunction, debilitating fatigue and chronic widespread pain that implicate the central nervous system. A hallmark complaint of subjects with Gulf War Illness is post-exertional malaise; defined as an exacerbation of symptoms following physical and/or mental effort. To study the causal relationship between exercise, the brain, and changes in symptoms, 28 Gulf War veterans and 10 controls completed an fMRI scan before and after two exercise stress tests to investigate serial changes in pain, autonomic function, and working memory. Exercise induced two clinical Gulf War Illness subgroups. One subgroup presented with orthostatic tachycardia (n = 10). This phenotype correlated with brainstem atrophy, baseline working memory compensation in the cerebellar vermis, and subsequent loss of compensation after exercise. The other subgroup developed exercise induced hyperalgesia (n = 18) that was associated with cortical atrophy and baseline working memory compensation in the basal ganglia. Alterations in cognition, brain structure, and symptoms were absent in controls. Our novel findings may provide an understanding of the relationship between the brain and post-exertional malaise in Gulf War Illness.

Summertime Acute Heat Illness in U.S. Emergency Departments from 2006 through 2010: Analysis of a Nationally Representative Sample

PubMed Central

Saha, Shubhayu; Luber, George

2014-01-01

Background: Patients with acute heat illness present primarily to emergency departments (EDs), yet little is known regarding these visits. Objective: We aimed to describe acute heat illness visits to U.S. EDs from 2006 through 2010 and identify factors associated with hospital admission or with death in the ED. Methods: We extracted ED case-level data from the Nationwide Emergency Department Sample (NEDS) for 2006–2010, defining cases as ED visits from May through September with any heat illness diagnosis (ICD-9-CM 992.0–992.9). We correlated visit rates and temperature anomalies, analyzed demographics and ED disposition, identified risk factors for adverse outcomes, and examined ED case fatality rates (CFR). Results: There were 326,497 (95% CI: 308,372, 344,658) cases, with 287,875 (88.2%) treated and released, 38,392 (11.8%) admitted, and 230 (0.07%) died in the ED. Heat illness diagnoses were first-listed in 68%. 74.7% had heat exhaustion, 5.4% heat stroke. Visit rates were highly correlated with annual temperature anomalies (Pearson correlation coefficient 0.882, p = 0.005). Treat-and-release rates were highest for younger adults (26.2/100,000/year), whereas hospitalization and death-in-the-ED rates were highest for older adults (6.7 and 0.03/100,000/year, respectively); all rates were highest in rural areas. Heat stroke had an ED CFR of 99.4/10,000 (95% CI: 78.7, 120.1) visits and was diagnosed in 77.0% of deaths. Adjusted odds of hospital admission or death in the ED were higher among elders, males, urban and low-income residents, and those with chronic conditions. Conclusions: Heat illness presented to the ED frequently, with highest rates in rural areas. Case definitions should include all diagnoses. Visit rates were correlated with temperature anomalies. Heat stroke had a high ED CFR. Males, elders, and the chronically ill were at greatest risk of admission or death in the ED. Chronic disease burden exponentially increased this risk. Citation: Hess JJ, Saha S, Luber G. 2014. Summertime acute heat illness in U.S. emergency departments from 2006 through 2010: analysis of a nationally representative sample. Environ Health Perspect 122:1209–1215; http://dx.doi.org/10.1289/ehp.1306796 PMID:24937159

Risk factors for heat illness among British soldiers in the hot Collective Training Environment

PubMed Central

Moore, Alice C; Stacey, M J; Bailey, K G H; Bunn, R J; Woods, D R; Haworth, K J; Brett, S J; Folkes, S E F

2016-01-01

Background Heat illness is a preventable disorder in military populations. Measures that protect vulnerable individuals and contribute to effective Immediate Treatment may reduce the impact of heat illness, but depend upon adequate understanding and awareness among Commanders and their troops. Objective To assess risk factors for heat illness in British soldiers deployed to the hot Collective Training Environment (CTE) and to explore awareness of Immediate Treatment responses. Methods An anonymous questionnaire was distributed to British soldiers deployed in the hot CTEs of Kenya and Canada. Responses were analysed to determine the prevalence of individual (Intrinsic) and Command-practice (Extrinsic) risk factors for heat illness and the self-reported awareness of key Immediate Treatment priorities (recognition, first aid and casualty evacuation). Results The prevalence of Intrinsic risk factors was relatively low in comparison with Extrinsic risk factors. The majority of respondents were aware of key Immediate Treatment responses. The most frequently reported factors in each domain were increased risk by body composition scoring, inadequate time for heat acclimatisation and insufficient briefing about casualty evacuation. Conclusions Novel data on the distribution and scale of risk factors for heat illness are presented. A collective approach to risk reduction by the accumulation of ‘marginal gains’ is proposed for the UK military. This should focus on limiting Intrinsic risk factors before deployment, reducing Extrinsic factors during training and promoting timely Immediate Treatment responses within the hot CTE. PMID:26036822

Medicines can affect thermoregulation and accentuate the risk of dehydration and heat-related illness during hot weather.

PubMed

Westaway, K; Frank, O; Husband, A; McClure, A; Shute, R; Edwards, S; Curtis, J; Rowett, D

2015-08-01

Hot days are increasingly common and are often associated with increased morbidity and mortality, especially in the elderly. Most heat-related illness and heat-related deaths are preventable. Medicines may accentuate the risk of dehydration and heat-related illness, especially in elderly people taking multiple medicines, through the following mechanisms: diuresis and electrolyte imbalance, sedation and cognitive impairment, changed thermoregulation, reduced thirst recognition, reduced sweat production, and hypotension and reduced cardiac output. Commonly used medicines that may significantly increase the risk include diuretics, especially when combined with an angiotensin converting enzyme (ACE) inhibitor or an angiotensin II receptor blocker (ARB), anticholinergics and psychotropics. Initiation of individualized preventive measures prior to the start of the hot weather season, which includes a review of the patient and their medicines to identify thermoregulatory issues, may reduce the risk of heat-related illness or death. © 2015 John Wiley & Sons Ltd.

Heat Illness: A Handbook for Medical Officers

DTIC Science & Technology

1991-06-03

Recommendations to planning staffs should eii~piliasve theC irportwnce of adequate sleep and food to reduce the likelihood of heat casuaRtift-ýs...experience much greater heat strain in uniforms, such as the BDO, that restrict heat exchange with the environment. Will the recruits have the...the sklf.- to thermoregulate and increase the risk of heat Illness. Lack of sleep and food will reduce thermoregiilatomy capacity. Medical Plannin-a

46 CFR 153.434 - Heat transfer coils within a tank.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment... the heat transfer fluid at a pressure greater than the pressure exerted on the heating or cooling...

Exertional heat stroke in navy and marine personnel: a hot topic.

PubMed

Goforth, Carl W; Kazman, Josh B

2015-02-01

Although exertional heat stroke is considered a preventable condition, this life-threatening emergency affects hundreds of military personnel annually. Because heat stroke is preventable, it is important that Navy critical care nurses rapidly recognize and treat heat stroke casualties. Combined intrinsic and extrinsic risk factors can quickly lead to heat stroke if not recognized by deployed critical care nurses and other first responders. In addition to initial critical care nursing interventions, such as establishing intravenous access, determining body core temperature, and assessing hemodynamic status, aggressive cooling measures should be initiated immediately. The most important determinant in heat stroke outcome is the amount of time that patients sustain hyperthermia. Heat stroke survival approaches 100% when evidence-based cooling guidelines are followed, but mortality from heat stroke is a significant risk when care is delayed. Navy critical care and other military nurses should be aware of targeted assessments and cooling interventions when heat stroke is suspected during military operations. ©2015 American Association of Critical-Care Nurses.

Individual and Public-Program Adaptation: Coping with Heat Waves in Five Cities in Canada

PubMed Central

Alberini, Anna; Gans, Will; Alhassan, Mustapha

2011-01-01

Heat Alert and Response Systems (HARS) are currently undergoing testing and implementation in Canada. These programs seek to reduce the adverse health effects of heat waves on human health by issuing weather forecasts and warnings, informing individuals about possible protections from excessive heat, and providing such protections to vulnerable subpopulations and individuals at risk. For these programs to be designed effectively, it is important to know how individuals perceive the heat, what their experience with heat-related illness is, how they protect themselves from excessive heat, and how they acquire information about such protections. In September 2010, we conducted a survey of households in 5 cities in Canada to study these issues. At the time of the survey, these cities had not implemented heat outreach and response systems. The study results indicate that individuals’ recollections of recent heat wave events were generally accurate. About 21% of the sample reported feeling unwell during the most recent heat spell, but these illnesses were generally minor. Only in 25 cases out of 243, these illnesses were confirmed or diagnosed by a health care professional. The rate at which our respondents reported heat-related illnesses was higher among those with cardiovascular and respiratory illnesses, was higher among younger respondents and bore no relationship with the availability of air conditioning at home. Most of the respondents indicated that they would not dismiss themselves as “not at risk” and that they would cope with excessive heat by staying in air conditioned environments and keeping well hydrated. Despite the absence of heat outreach and education programs in their city, our respondents at least a rough idea of how to take care of themselves. The presence of air conditioning and knowledge of cooling centers is location-specific, which provides opportunities for targeting HARS interventions. PMID:22408596

Strategies and factors associated with preparing for competing in the heat: a cohort study at the 2015 IAAF World Athletics Championships

PubMed Central

Périard, Julien D; Racinais, Sébastien; Dahlström, Örjan; Spreco, Armin; Bargoria, Victor; Halje, Karin; Alonso, Juan-Manuel

2017-01-01

Purpose Assess exertional heat illness (EHI) history and preparedness in athletes competing in a World Athletics Championships under hot/humid conditions and identify the factors associated with preparedness strategies. Methods Of the 207 registered national teams invited to participate in the study, 50 (24%) accepted. The 957 athletes (49% of all 1965 registered) in these teams were invited to complete a precompetition questionnaire evaluating EHI history, heat stress prevention (heat acclimatisation, precooling and hydration) and recovery. Responses from 307 (32%) athletes were separated in field events, sprints, middle-distance and long-distance running, and decathlon/heptathlon for analysis. Results 48% of athletes had previously experienced EHI symptoms and 8.5% had been diagnosed with EHI. 15% heat acclimatised (∼20 days) before the championships. 52% had a precooling strategy, ice slurry ingestion (24%) being the most prevalent and women using it more frequently than men (p=0.005). 96% of athletes had a fluid consumption strategy, which differed between event categories (p<0.001). The most common volumes planned on being consumed were 0.5–1 L (27.2%) and ≥2 L (21.8%), water being the most frequent. 89% of athletes planned on using at least one recovery strategy. Female sex (p=0.024) and a previous EHI diagnosis increased the likelihood of using all 3 prevention strategies (p<0.001). Conclusions At a World Championships with expected hot/humid conditions, less than one-fifth of athletes heat acclimatised, half had a precooling strategy and almost all a hydration plan. Women, and especially athletes with an EHI history, were more predisposed to use a complete heat stress prevention strategy. More information regarding heat acclimatisation should be provided to protect athlete health and optimise performance at major athletics competitions in the heat. PMID:27815238

Water Replacement Schedules in Heat Stress

ERIC Educational Resources Information Center

Londeree, Ben R.; and others

1969-01-01

Although early ingestion of cold water appears to lead to greater relief from heat stress during physical exertion than late ingestion, this difference is reduced toward the end of an hour's work in high heat and humidity. (CK)

Temperature-Related Death and Illness. Chapter 2

NASA Technical Reports Server (NTRS)

Sarofim, Marcus C.; Saha, Shubhayu; Hawkins, Michelle D.; Mills, David M.; Hess, Jeremy; Horton, Radley; Kinney, Patrick; Schwartz, Joel; St. Juliana, Alexis

2016-01-01

Based on present-day sensitivity to heat, an increase of thousands to tens of thousands of premature heat-related deaths in the summer and a decrease of premature cold-related deaths in the winter are projected each year as a result of climate change by the end of the century. Future adaptation will very likely reduce these impacts (see Changing Tolerance to Extreme Heat Finding). The reduction in cold-related deaths is projected to be smaller than the increase in heat-related deaths in most regions. Days that are hotter than usual in the summer or colder than usual in the winter are both associated with increased illness and death. Mortality effects are observed even for small differences from seasonal average temperatures. Because small temperature differences occur much more frequently than large temperature differences, not accounting for the effect of these small differences would lead to underestimating the future impact of climate change. An increase in population tolerance to extreme heat has been observed over time. Changes in this tolerance have been associated with increased use of air conditioning, improved social responses, and or physiological acclimatization, among other factors. Expected future increases in this tolerance will reduce the projected increase in deaths from heat. Older adults and children have a higher risk of dying or becoming ill due to extreme heat. People working outdoors, the socially isolated and economically disadvantaged, those with chronic illnesses, as well as some communities of color, are also especially vulnerable to death or illness.

The potential impacts of climate variability and change on temperature-related morbidity and mortality in the United States.

PubMed

McGeehin, M A; Mirabelli, M

2001-05-01

Heat and heat waves are projected to increase in severity and frequency with increasing global mean temperatures. Studies in urban areas show an association between increases in mortality and increases in heat, measured by maximum or minimum temperature, heat index, and sometimes, other weather conditions. Health effects associated with exposure to extreme and prolonged heat appear to be related to environmental temperatures above those to which the population is accustomed. Models of weather-mortality relationships indicate that populations in northeastern and midwestern U.S. cities are likely to experience the greatest number of illnesses and deaths in response to changes in summer temperature. Physiologic and behavioral adaptations may reduce morbidity and mortality. Within heat-sensitive regions, urban populations are the most vulnerable to adverse heat-related health outcomes. The elderly, young children, the poor, and people who are bedridden or are on certain medications are at particular risk. Heat-related illnesses and deaths are largely preventable through behavioral adaptations, including the use of air conditioning and increased fluid intake. Overall death rates are higher in winter than in summer, and it is possible that milder winters could reduce deaths in winter months. However, the relationship between winter weather and mortality is difficult to interpret. Other adaptation measures include heat emergency plans, warning systems, and illness management plans. Research is needed to identify critical weather parameters, the associations between heat and nonfatal illnesses, the evaluation of implemented heat response plans, and the effectiveness of urban design in reducing heat retention.

The descriptive epidemiology of sports/leisure-related heat illness hospitalisations in New South Wales, Australia.

PubMed

Finch, Caroline F; Boufous, Soufiane

2008-01-01

Sport-related heat illness has not been commonly studied from an epidemiological perspective. This study presents the descriptive epidemiology of sports/leisure-related heat illness hospitalisations in New South Wales, Australia. All in-patient separations from all acute hospitals in NSW during 2001-2004, with an International Classification of Diseases external cause of injury code indicating "exposure to excessive natural heat (X30)" or any ICD-10 diagnosis code in the range: "effects of heat and light (T67.0-T67.9)", were analysed. The sport/leisure relatedness of cases was defined by ICD-10-AM activity codes indicating involvement in sport/leisure activities. Cases of exposure to heat while engaged in sport/leisure were described by gender, year, age, principal diagnosis, type of activity/sport and length of stay. There were 109 hospital separations for exposure to heat while engaging in sport/leisure activity, with the majority occurring during the hottest months. The number of male cases significantly increased over the 4-year period and 45+ -year olds had the largest number of cases. Heat exhaustion was the leading cause of hospital separation (40% of cases). Marathon running, cricket and golf were the activities most commonly associated with heat-related hospitalisation. Ongoing development and refinement of expert position statements regarding heat illnesses need to draw on both epidemiological and physiological evidence to ensure their relevance to all levels of risk from the real world sport training and competition contexts.

Fitness, obesity and risk of heat illness among army trainees.

PubMed

Bedno, S A; Urban, N; Boivin, M R; Cowan, D N

2014-09-01

Exertional heat illness (EHI) affects military personnel, athletes and occupational groups such as agricultural workers, despite knowledge of preventive measures. To evaluate EHI diagnoses during US Army basic training and its associations with fitness and body fat on entering military service. From February 2005 to September 2006, US Army recruits at six different military entrance stations took a pre-accession fitness test, including a 5-min step test scored as pass or fail. Subsequent EHI incidence and incidence rate ratios were analysed with reference to subjects' fitness (step test performance) and whether they met (weight qualified [WQ]) or exceeded body fat (EBF) standards. Among the 8621 WQ and 834 EBF male subjects, there were 67 incidents of EHI within 180 days of entering military service. Among WQ subjects, step test failure was significantly associated with EHI (odds ratio [OR] 2.00, 95% confidence interval [CI] 1.13, 3.53). For those passing the step test, the risk of EHI was significantly higher in EBF than in WQ subjects (OR 3.98, 95% CI 2.17, 7.29). Expected ORs for the joint effects of step test failure and EBF classification under additive and multiplicative models were 4.98 and 7.96, respectively. There were too few women to evaluate their data in detail. This study demonstrated that fitness and body fat are independently associated with incident EHI, and the effect of both was substantially higher. Those with low fitness levels and/or obesity should be evaluated further before engaging in intense physical activity, especially in warmer months. Published by Oxford University Press on behalf of the Society of Occupational Medicine 2014.This work is written by (a) US Government employee(s) and is in the public domain in the US.

46 CFR 153.434 - Heat transfer coils within a tank.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Heat transfer coils within a tank. 153.434 Section 153... Cargo Temperature Control Systems § 153.434 Heat transfer coils within a tank. When a cargo tank... the heat transfer fluid at a pressure greater than the pressure exerted on the heating or cooling...

46 CFR 153.434 - Heat transfer coils within a tank.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Heat transfer coils within a tank. 153.434 Section 153... Cargo Temperature Control Systems § 153.434 Heat transfer coils within a tank. When a cargo tank... the heat transfer fluid at a pressure greater than the pressure exerted on the heating or cooling...

46 CFR 153.434 - Heat transfer coils within a tank.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Heat transfer coils within a tank. 153.434 Section 153... Cargo Temperature Control Systems § 153.434 Heat transfer coils within a tank. When a cargo tank... the heat transfer fluid at a pressure greater than the pressure exerted on the heating or cooling...

46 CFR 153.434 - Heat transfer coils within a tank.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Heat transfer coils within a tank. 153.434 Section 153... Cargo Temperature Control Systems § 153.434 Heat transfer coils within a tank. When a cargo tank... the heat transfer fluid at a pressure greater than the pressure exerted on the heating or cooling...

Camelid heat stress: 15 cases (2003–2011)

PubMed Central

Norton, Piper L.; Gold, Jenifer R.; Russell, Karen E.; Schulz, Kara L.; Porter, Brian F.

2014-01-01

This case series describes novel findings associated with heat stress in 15 cases in South American camelids that had no pre-existing illnesses and which had clinical signs of illness after exposure to a warm environment. Novel findings include decreased packed cell volume and albumin concentration and mild spinal axonal degeneration. Heat stress should be considered in weak camelids with a history of hyperthermia. PMID:25320390

The Epidemiology of Occupational Heat-Related Morbidity and Mortality in the United States: A Review of the Literature and Assessment of Research Needs in a Changing Climate

PubMed Central

Gubernot, Diane M.; Anderson, G. Brooke; Hunting, Katherine L.

2014-01-01

In recent years, the United States has experienced record-breaking summer heat. Climate change models forecast increasing U.S. temperatures and more frequent heat waves in coming years. This scoping review summarizes research findings that characterize U.S. occupational heat-related morbidity and mortality and identifies gaps in the existing research literature. Exposure to environmental heat is a significant, but overlooked, workplace hazard that has not been well-characterized or studied. The working population is diverse; job function, age, fitness level, and risk factors to heat-related illnesses vary. This review found that few studies examine or characterize the incidence of occupational heat-related illnesses and outcomes. More research on the effects of occupational heat exposure is needed to identify and implement evidence-based policies and interventions. Since heat-related health hazards at work can be anticipated before they manifest, preventive measures can be implemented before illness occurs. With no federal regulatory standards to protect workers from environmental heat exposure, and with climate change as a driver for adaptation and prevention of heat disorders, crafting policy to characterize and prevent occupational heat stress for all workers is increasingly sensible, practical, and imperative. PMID:24326903

Heat Stress Illness in a Mechanized Infantry Brigade During Simulated Combat at Fort Irwin

DTIC Science & Technology

1994-05-01

this expanded concept of risk measurement and tracking, at least partly, feasible. Year(s) # heat Primary (Sumncr only) illnesses/10.000/week Activity...operations. Inibntly 28-34, May-June 1992. Clowes, G.H.A., and O’Donnell, T.F. Jr. Current concepts : heat stroke. New England Journal of Medicine 291(11...V.M.. Role of dehydration in heat stress-induced variations in mental performance. Archives of Environmental Healh 43: 15-17, 1988. Halbertstadt, Hans

A randomized controlled trial of aspirin and exertional heat stress activation of platelets in firefighters during exertion in thermal protective clothing.

PubMed

Hostler, David; Suyama, Joe; Guyette, Francis X; Moore, Charity G; Pryor, Riana R; Khorana, Priya; McEntire, Serina J; Comer, Diane; Reis, Steven E

2014-01-01

Platelet aggregation is enhanced in firefighters following short bouts of work in thermal protective clothing (TPC). We sought to determine if aspirin therapy before and/or following exertion in TPC prevents platelet activation. In a double-blind, placebo-controlled study, 102 firefighters were randomized to receive daily therapy (81 mg aspirin or placebo) for 14 days before and a single dose (325 mg aspirin or placebo) following exercise in TPC resulting in four potential assignments: aspirin before and after exercise (AA), placebo before and after exercise (PP), aspirin before and placebo after exercise (AP), and placebo before and aspirin after exercise (PA). Platelet closure time (PCT) was measured with a platelet function analyzer before the 2-week treatment, after the 2 week treatment period, immediately after exercise, and 30, 60, and 90 minutes later. Baseline PCT did not differ between groups. PCT changed over time in all four groups (p < 0.001) rising to a median of >300 seconds [IQR 99, 300] in AA and >300 [92, 300] in AP prior to exercise. Following exercise, median PCT decreased to in all groups. Median PCT returned to >300 seconds 30 minutes later in AA and AP and rose to 300 seconds in PA 60 minutes after exercise. Daily aspirin therapy blunts platelet activation during exertional heat stress and single-dose aspirin therapy following exertional heat stress reduces platelet activation within 60 minutes.

Community Trial on Heat Related-Illness Prevention Behaviors and Knowledge for the Elderly

PubMed Central

Takahashi, Noriko; Nakao, Rieko; Ueda, Kayo; Ono, Masaji; Kondo, Masahide; Honda, Yasushi; Hashizume, Masahiro

2015-01-01

This study aims to explore whether broadcasting heat health warnings (HHWs), to every household and whether the additional home delivery of bottled water labeled with messages will be effective in improving the behaviors and knowledge of elderly people to prevent heat-related illness. A community trial on heat-related-illness-prevention behaviors and knowledge for people aged between 65 and 84 years was conducted in Nagasaki, Japan. Five hundred eight subjects were selected randomly from three groups: heat health warning (HHW), HHW and water delivery (HHW+W), and control groups. Baseline and follow-up questionnaires were conducted in June and September 2012, respectively. Of the 1524 selected subjects, the 1072 that completed both questionnaires were analyzed. The HHW+W group showed improvements in nighttime AC use (p = 0.047), water intake (p = 0.003), cooling body (p = 0.002) and reduced activities in heat (p = 0.047) compared with the control, while the HHW group improved hat or parasol use (p = 0.008). An additional effect of household water delivery was observed in water intake (p = 0.067) and cooling body (p = 0.095) behaviors. HHW and household bottled water delivery improved heat-related-illness-prevention behaviors. The results indicate that home water delivery in addition to a HHW may be needed to raise awareness of the elderly. PMID:25789456

Risk characterization of hospitalizations for mental illness and/or behavioral disorders with concurrent heat-related illness

PubMed Central

2017-01-01

Background Many studies have found significant associations between high ambient temperatures and increases in heat-related morbidity and mortality. Several studies have demonstrated that increases in heat-related hospitalizations are elevated among individuals with diagnosed mental illnesses and/or behavioral disorders (MBD). However, there are a limited number of studies regarding risk factors associated with specific mental illnesses that contribute, at least in part, to heat-related illnesses (HRI) in the United States. Objective To identify and characterize individual and environmental risk factors associated with MBD hospitalizations with a concurrent HRI diagnosis. Methods This study uses hospitalization data from the Nationwide Inpatient Sample (2001–2010). Descriptive analyses of primary and secondary diagnoses of MBDs with an HRI were examined. Risk ratios (RR) were calculated from multivariable models to identify risk factors for hospitalizations among patients with mental illnesses and/or behavioral disorders and HRI. Results Nondependent alcohol/drug abuse, dementia, and schizophrenia were among the disorders that were associated with increased frequency of HRI hospitalizations among MBD patients. Increased risk of MBD hospitalizations with HRI was observed for Males (RR, 3.06), African Americans (RR, 1.16), Native Americans (RR, 1.70), uninsured (RR, 1.92), and those 40 years and older, compared to MBD hospitalizations alone. Conclusions Previous studies outside the U.S. have found that dementia and schizophrenia are significant risk factors for HRI hospitalizations. Our results suggest that hospitalizations among substance abusers may also be an important risk factor associated with heat morbidity. Improved understanding of these relative risks could help inform future public health strategies. PMID:29036206

Solar powered automobile automation for heatstroke prevention

NASA Astrophysics Data System (ADS)

Singh, Navtej Swaroop; Sharma, Ishan; Jangid, Santosh

2016-03-01

Heatstroke inside a car has been critical problem in every part of the world. Non-exertional heat stroke results from exposure to a high environmental temperature. Exertional heat stroke happens from strenuous exercise. This paper presents a solution for this fatal problem and proposes an embedded solution, which is cost effective and shows the feasibility in implementation. The proposed system consists of information sharing platform, interfacing of sensors, Global System Mobile (GSM), real time monitoring system and the system is powered by the solar panel. The system has been simulated and tested with experimental setup.

Effect of aspirin on acute changes in peripheral arterial stiffness and endothelial function following exertional heat stress in firefighters: The factorial group results of the Enhanced Firefighter Rehab Trial.

PubMed

Olafiranye, Oladipupo; Hostler, David; Winger, Daniel G; Wang, Li; Reis, Steven E

2015-06-01

Peripheral arterial stiffness and endothelial function, which are independent predictors of cardiac events, are abnormal in firefighters. We examined the effects of aspirin on peripheral arterial stiffness and endothelial function in firefighters. Fifty-two firefighters were randomized to receive daily 81 mg aspirin or placebo for 14 days before treadmill exercise in thermal protection clothing, and a single dose of 325 mg aspirin or placebo immediately following exertion. Peripheral arterial augmentation index adjusted for a heart rate of 75 (AI75) and reactive hyperemia index (RHI) were determined immediately before, and 30, 60, and 90 minutes after exertion. Low-dose aspirin was associated with lower AI75 (-15.25±9.25 vs -8.08±10.70, p=0.014) but not RHI. On repeated measures analysis, treatment with low-dose aspirin before, but not single-dose aspirin after exertion, was associated with lower AI75 following exertional heat stress (p=0.018). Low-dose aspirin improved peripheral arterial stiffness and wave reflection but not endothelial function in firefighters. © The Author(s) 2015.

Cooling vest

NASA Technical Reports Server (NTRS)

Kosmo, J.; Kane, J.; Coverdale, J.

1977-01-01

Inexpensive vest of heat-sealable urethane material, when strapped to person's body, presents significant uncomplicated cooling system for environments where heavy accumulation of metabolic heat exists. Garment is applicable to occupations where physical exertion is required under heavy protective clothing.

A Functional Return-to-Play Progression After Exertional Heat Stroke in a High School Football Player.

PubMed

Lopez, Rebecca M; Tanner, Patrick; Irani, Sarah; Mularoni, P Patrick

2018-03-01

  To present a functional return-to-play (RTP) progression after exertional heat stroke (EHS) in a 17-year-old high school football defensive end (height = 185 cm, mass = 145.5 kg).   The patient had no pertinent medical history but moved to a warm climate several days before the EHS occurred. After completing an off-season conditioning test (14- × 110-yd [12.6- × 99.0-m] sprints) on a warm afternoon (temperature = approximately 34°C [93°F], relative humidity = 53%), the patient collapsed. An athletic trainer (AT) was called to the field, where he found the patient conscious but exhibiting central nervous system dysfunction. Emergency medical services were summoned and immediately transported the patient to the hospital.   Exertional heat stroke, heat exhaustion, exertional sickling, rhabdomyolysis, and cardiac arrhythmia.   The patient was immediately transported to a hospital, where his oral temperature was 39.6°C (103.3°F). He was transferred to a children's hospital and treated for rhabdomyolysis, transaminitis, and renal failure. He was hospitalized for 11 days. After a physician's clearance once the laboratory results normalized, an RTP progression was completed. The protocol began with light activity and progressed over 3 weeks to full football practice. During activity, an AT monitored the patient's gastrointestinal temperature, heart rate, rating of perceived exertion, fluid consumption, and sweat losses.   Documentation of RTP guidelines for young athletes is lacking. We used a protocol intended for the football setting to ensure the athlete was heat tolerant, had adequate physical fitness, and could safely RTP. Despite his EHS, he recovered fully, with no lasting effects, and successfully returned to compete in the final 5 games of the season.   Using a gradual RTP progression and close monitoring, a high school defensive end successfully returned to football practice and games after EHS. This case demonstrates the feasibility of implementing a safe RTP protocol after EHS and may serve as a guide to ATs working in the high school setting. This case also highlights the need for more research in this area.

Strategies and factors associated with preparing for competing in the heat: a cohort study at the 2015 IAAF World Athletics Championships.

PubMed

Périard, Julien D; Racinais, Sébastien; Timpka, Toomas; Dahlström, Örjan; Spreco, Armin; Jacobsson, Jenny; Bargoria, Victor; Halje, Karin; Alonso, Juan-Manuel

2017-02-01

Assess exertional heat illness (EHI) history and preparedness in athletes competing in a World Athletics Championships under hot/humid conditions and identify the factors associated with preparedness strategies. Of the 207 registered national teams invited to participate in the study, 50 (24%) accepted. The 957 athletes (49% of all 1965 registered) in these teams were invited to complete a precompetition questionnaire evaluating EHI history, heat stress prevention (heat acclimatisation, precooling and hydration) and recovery. Responses from 307 (32%) athletes were separated in field events, sprints, middle-distance and long-distance running, and decathlon/heptathlon for analysis. 48% of athletes had previously experienced EHI symptoms and 8.5% had been diagnosed with EHI. 15% heat acclimatised (∼20 days) before the championships. 52% had a precooling strategy, ice slurry ingestion (24%) being the most prevalent and women using it more frequently than men (p=0.005). 96% of athletes had a fluid consumption strategy, which differed between event categories (p<0.001). The most common volumes planned on being consumed were 0.5-1 L (27.2%) and ≥2 L (21.8%), water being the most frequent. 89% of athletes planned on using at least one recovery strategy. Female sex (p=0.024) and a previous EHI diagnosis increased the likelihood of using all 3 prevention strategies (p<0.001). At a World Championships with expected hot/humid conditions, less than one-fifth of athletes heat acclimatised, half had a precooling strategy and almost all a hydration plan. Women, and especially athletes with an EHI history, were more predisposed to use a complete heat stress prevention strategy. More information regarding heat acclimatisation should be provided to protect athlete health and optimise performance at major athletics competitions in the heat. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Preventing heat illness in the anticipated hot climate of the Tokyo 2020 Summer Olympic Games.

PubMed

Kakamu, Takeyasu; Wada, Koji; Smith, Derek R; Endo, Shota; Fukushima, Tetsuhito

2017-09-19

Amid the effects of global warming, Tokyo has become an increasingly hot city, especially during the summertime. To prepare for the upcoming 2020 Summer Olympics and Paralympics in Tokyo, all participants, including the athletes, staff, and spectators, will need to familiarize themselves with Tokyo's hot and humid summer conditions. This paper uses the wet-bulb globe temperature (WBGT) index, which estimates the risk of heat illness, to compare climate conditions of sports events in Tokyo with the conditions of the past three Summer Olympics (held in Rio de Janeiro, London, and Beijing) and to subsequently detail the need for establishing appropriate countermeasures. We compared WBGT results from the past three Summer Olympics with the same time periods in Tokyo during 2016. There was almost no time zone where a low risk of heat illness could be expected during the time frame of the upcoming 2020 Tokyo Olympics. We also found that Tokyo had a higher WBGT than any of those previous host cities and is poorly suited for outdoor sporting events. Combined efforts by the official organizers, government, various related organizations, and the participants will be necessary to deal with these challenging conditions and to allow athletes to perform their best, as well as to prevent heat illnesses among staff and spectators. The sporting committees, as well as the Olympic organizing committee, should consider WBGT measurements in determining the venues and timing of the events to better avoid heat illness and facilitate maximum athletic performance.

Exertional heat stroke and acute liver failure: a late dysfunction

PubMed Central

Carvalho, Ana Sofia; Rodeia, Simão C; Silvestre, Joana; Póvoa, Pedro

2016-01-01

Heat stroke (HS) is defined as a severe elevation of core body temperature along with central nervous system dysfunction. Exertional heat stroke (EHS) with acute liver failure (ALF) is a rare condition. The authors report the case of a 25-year-old man with a history of cognitive enhancers’ intake who developed hyperthermia and neurological impairment while running an outdoor marathon. The patient was cooled and returned to normal body temperature after 6 h. He subsequently developed ALF and was transferred to the intensive care unit. Over-the-counter drug intake may have been related to heat intolerance and contributed to the event. The patient was successfully treated with conservative measures. In the presence of EHS, it is crucial to act promptly with aggressive total body cooling, in order to prevent progression of the clinical syndrome. Liver function must also be monitored, since it can be a late organ dysfunction. PMID:26969359

Human behavioral thermoregulation during exercise in the heat.

PubMed

Flouris, A D; Schlader, Z J

2015-06-01

The human capacity to perform prolonged exercise is impaired in hot environments. To address this issue, a number of studies have investigated behavioral aspects of thermoregulation that are recognized as important factors in determining performance. In this review, we evaluated and interpreted the available knowledge regarding the voluntary control of exercise work rate in hot environments. Our analysis indicated that: (a) Voluntary reductions in exercise work rate in uncompensable heat aid thermoregulation and are, therefore, thermoregulatory behaviors. (b) Unlike thermal behavior during rest, the role of thermal comfort as the ultimate mediator of thermal behavior during exercise in the heat remains uncertain. By contrast, the rating of perceived exertion appears to be the key perceptual controller under such conditions, with thermal perception playing a more modulatory role. (c) Prior to increases in core temperature (when only skin temperature is elevated), reductions in self-selected exercise work rate in the heat are likely mediated by thermal perception (thermal comfort and sensation) and its influence on the rating of perceived exertion. (d) However, when both core and skin temperatures are elevated, factors associated with cardiovascular strain likely dictate the rate of perceived exertion response, thereby mediating such voluntary reductions in exercise work rate. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Heat-related symptoms in sugarcane harvesters.

PubMed

Crowe, Jennifer; Nilsson, Maria; Kjellstrom, Tord; Wesseling, Catharina

2015-05-01

Exposure to heat stress is a documented risk for Central American sugarcane harvesters. However, little is known about heat-related illness in this population. This study examined the frequency of heat-related health effects among harvesters (n = 106) exposed to occupational heat stress compared to non-harvesters (n = 63). Chi-square test and gamma statistic were used to evaluate differences in self-reported symptoms and trends over heat exposure categories. Heat and dehydration symptoms (headache, tachycardia, muscle cramps, fever, nausea, difficulty breathing, dizziness, swelling of hands/feet, and dysuria) were experienced at least once per week significantly more frequently among harvesters. Percentages of workers reporting heat and dehydration symptoms increased in accordance with increasing heat exposure categories. A large percentage of harvesters are experiencing heat illness throughout the harvest demonstrating an urgent need for improved workplace practices, particularly in light of climate change and the epidemic of chronic kidney disease prevalent in this population. © 2015 Wiley Periodicals, Inc.

Climatic and psychosocial risks of heat illness incidents on construction site.

PubMed

Jia, Yunyan Andrea; Rowlinson, Steve; Ciccarelli, Marina

2016-03-01

The study presented in this paper aims to identify prominent risks leading to heat illness in summer among construction workers that can be prioritised for developing effective interventions. Samples are 216 construction workers' cases at the individual level and 26 construction projects cases at the organisation level. A grounded theory is generated to define the climatic heat and psychosocial risks and the relationships between risks, timing and effectiveness of interventions. The theoretical framework is then used to guide content analysis of 36 individual onsite heat illness cases to identify prominent risks. The results suggest that heat stress risks on construction site are socially constructed and can be effectively managed through elimination at supply chain level, effective engineering control, proactive control of the risks through individual interventions and reactive control through mindful recognition and response to early symptoms. The role of management infrastructure as a base for effective interventions is discussed. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Levosimendan in Critical Illness: A Literature Review

PubMed Central

Pierrakos, Charalampos; Velissaris, Dimitrios; Franchi, Federico; Muzzi, Luigi; Karanikolas, Menelaos; Scolletta, Sabino

2014-01-01

Levosimendan, the active enantiomer of simendan, is a calcium sensitizer developed for treatment of decompensated heart failure, exerts its effects independently of the beta adrenergic receptor and seems beneficial in cases of severe, intractable heart failure. Levosimendan is usually administered as 24-h infusion, with or without a loading dose, but dosing needs adjustment in patients with severe liver or renal dysfunction. Despite several promising reports, the role of levosimendan in critical illness has not been thoroughly evaluated. Available evidence suggests that levosimendan is a safe treatment option in critically ill patients and may reduce mortality from cardiac failure. However, data from well-designed randomized controlled trials in critically ill patients are needed to validate or refute these preliminary conclusions. This literature review is an attempt to synthesize available evidence on the role and possible benefits of levosimendan in critically ill patients with severe heart failure. PMID:24578748

Exogenous salicylic acid enhances the resistance of wheat seedlings to hessian fly (Diptera: Cecidomyiidae) infestation under heat stress

USDA-ARS?s Scientific Manuscript database

Heat stress exerts significant impact on plant-parasite interactions. Phytohormones, such as salicylic acid (SA) play important roles in plant defense against parasite attacks. Here we studied the impact of a combination of heat stress and exogenous SA on wheat (Triticum aestivum L.) plant resistanc...

Transient heat-stress compromises the resistance of wheat seedlings to Hessian fly (Diptera: Cecidomyiidae) infestation

USDA-ARS?s Scientific Manuscript database

Heat-stress exerts profound impact on resistance of plants to parasites. In this research, we investigated the impact of an acute, transient heat-stress on the resistance of the wheat line 'Molly', which contains the resistance gene H13, to an avirulent Hessian fly [Mayetiola destructor (Say)] popu...

Effects of physical conditioning on heat tolerance in chemical-defense gear. Master's thesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nauss, M.M.

Today the threat of chemical warfare is real. The only effective defense is the use of chemical defense gear and gas masks. Since they render chemical-warfare gases and liquids impermeable to penetration, they also prohibit sweat evaporation in conditions of thermal stress and thus, contribute to heat illness development. Historically, it has been the hot, humid tropics where United Nation's peacekeeping forces have been called, thus the use of chemical-defense gear in these regions is a realistic possibility and heat illness could affect the outcome of any mission carried out there. The human body only operates within a narrow rangemore » of core temparatures, and heat illness is the result of a breakdown in homeostasis. Many factors influence heat tolerance, thus maintaining core temperature within a safe range. Adequate hydration, acclimitization to heat, low body weight, young age, low alcohol intake, and physical fitness all contribute to heat tolerance. This proposal attempts to look specifically at the effect of physical conditioning on heat tolerance in chemical-defense gear as a possible solution to the heat-stress problem noted in this gear. Trainee graduates attending technical training schools at Lackland AFB, Texas, will be tested for maximum oxygen uptake (VO/2max) and heat tolerance time (HTT) in chemical defense gear on bicycle ergometers at Brooks AFB, Texas. Half of these subjects will be physically conditioned for 12 weeks.« less

Recruitment, Methods, and Descriptive Results of a Physiologic Assessment of Latino Farmworkers: The California Heat Illness Prevention Study.

PubMed

Mitchell, Diane C; Castro, Javier; Armitage, Tracey L; Vega-Arroyo, Alondra J; Moyce, Sally C; Tancredi, Daniel J; Bennett, Deborah H; Jones, James H; Kjellstrom, Tord; Schenker, Marc B

2017-07-01

The California heat illness prevention study (CHIPS) devised methodology and collected physiological data to assess heat related illness (HRI) risk in Latino farmworkers. Bilingual researchers monitored HRI across a workshift, recording core temperature, work rate (metabolic equivalents [METs]), and heart rate at minute intervals. Hydration status was assessed by changes in weight and blood osmolality. Personal data loggers and a weather station measured exposure to heat. Interviewer administered questionnaires were used to collect demographic and occupational information. California farmworkers (n = 588) were assessed. Acceptable quality data was obtained from 80% of participants (core temperature) to 100% of participants (weight change). Workers (8.3%) experienced a core body temperature more than or equal to 38.5 °C and 11.8% experienced dehydration (lost more than 1.5% of body weight). Methodology is presented for the first comprehensive physiological assessment of HRI risk in California farmworkers.

Effectiveness of exercise-heat acclimation for preventing heat illness in the workplace.

PubMed

Yamazaki, Fumio

2013-09-01

The incidence of heat-related illness in the workplace is linked to whether or not workers have acclimated to a hot environment. Heat acclimation improves endurance work performance in the heat and thermal comfort at a given work rate. These improvements are achieved by increased sweating and skin blood flow responses, better fluid balance and cardiovascular stability. As a practical means of acclimatizing the body to heat stress, daily aerobic exercise training is recommended since thermoregulatory capacity and blood volume increase with physical fitness. In workers wearing personal protective suits in hot environments, however, little psychophysiological benefit is received from short-term exercise training and/or heat acclimation because of the ineffectiveness of sweating for heat dissipation and the aggravation of thermal discomfort with the accumulation of sweat within the suit. For a manual laborer who works under uncompensable heat stress, better management of the work rate, the work environment and health is required.

On the use of wearable physiological monitors to assess heat strain during occupational heat stress.

PubMed

Notley, Sean R; Flouris, Andreas D; Kenny, Glen P

2018-05-04

Workers in many industries are required to perform arduous work in high heat stress conditions, which can lead to rapid increases in body temperature that elevate the risk of heat-related illness or even death. Traditionally, effort to mitigate work-related heat injury has been directed to the assessment of environmental heat stress (e.g., wet-bulb globe temperature), rather than the associated physiological strain responses (e.g., heart rate, skin and core temperatures). However, since a workers physiological response to a given heat stress is modified independently by inter-individual factors (e.g., age, sex, chronic disease, others) and intra-individual factors both within (e.g., medication use, fitness, acclimation and hydration state, others) and beyond a workers control (e.g., shift duration, illness, others), it becomes challenging to protect workers on an individual basis from heat-related injury without assessing those physiological responses. Recent advancements in wearable technology have made it possible to monitor one or more physiological indices of heat strain. Nonetheless, information on the utility of the wearable systems available for assessing occupational heat strain is unavailable. This communication is therefore directed at identifying the physiological indices of heat strain that may be quantified in the workplace and evaluating the wearable monitoring systems available for assessing those responses. Finally, emphasis is directed to the barriers associated with implementing these devices to assist in mitigating work-related heat injury. This information is fundamental for protecting worker health and could also be utilized to prevent heat illnesses in vulnerable people during leisure or athletic activities in the heat.

Design and construction of Thermoelectric Footwear Heating System for illness feet.

PubMed

Işik, Hakan

2005-12-01

In this study, a Thermoelectric Footwear Heating System is developed to use in cold weather conditions. The temperature is controlled by an analog electronic control system. Thermoelectric module is used to heat the bottom of the foot. A negative temperature coefficient (NTC) temperature sensor is used to sense the temperature and the temperature is controlled by an electronic circuit proportionally. A 3.5 V, 5000 mAh rechargeable battery is used as the power source. The temperature range of the system is between +15 degrees C and +50 degrees C. Developed footwear heating system is tested against various temperature conditions, and offer better results in the case of heating the illness feet.

Amino acids as central synaptic transmitters or modulators in mammalian thermoregulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bligh, J.

1981-11-01

Of the amino acids that affect the activity of central neurons, aspartate and glutamate (which exert generally excitatory influences) and glycine, taurine, and ..gamma..-aminobutyric acid (GABA) (which generally exert inhibitory influences) are the strongest neurotransmitter candidates. As with other putative transmitter substances, their effects on body temperature when injected into the cerebral ventricles or the preoptic hypothalamus tend to vary within and between species. These effects are uninterpretable without accompanying information regarding effector activity changes and the influences of dose and ambient temperature. Observations necessary for analysis of apparent action have been made in studies of the effects of intracerebroventricularmore » injections of these amino acids into sheep. Aspartate and glutamate have similar excitatory effects on the pathway from cold sensors, whereas taurine and GABA exert inhibitory influences on the neural pathways that activate both heat production and heat loss effectors. Glycine appears to be without effect.« less

Short-Term, Low-Volume Training Improves Heat Acclimatization in an Operational Context

PubMed Central

Charlot, Keyne; Tardo-Dino, Pierre-Emmanuel; Buchet, Jean-François; Koulmann, Nathalie; Bourdon, Stéphanie; Lepetit, Benoit; Roslonski, Martin; Jousseaume, Loïc; Malgoyre, Alexandra

2017-01-01

Personnel who travel to areas with a hot climate (WBGT > 27°C) may suffer from the heat (physiological strain, thermal discomfort, increased probability of heat illness), making them partially or fully inoperative. Performing physical activities during heat acclimatization is known to improve this process (i.e., improve measures of acclimatization for the same duration of acclimation). However, it is unknown whether such training would be efficient in an operative context, characterized by a high volume of work-related physical activity. Thirty French soldiers (Training group, T) performed a short (5 days), progressive, moderate (from three to five 8-min running sets at 50% of the speed at VO2max for 32–56 min) aerobic training program upon arriving at their base in United Arab Emirates (~40°C and 12% RH). A control group (30 soldiers; No Training, NT) continued to perform their usual outdoor military activities (~6 h.d−1). A field heat stress test (HST; three 8-min running sets at 50% of the speed at VO2max) was performed, before and after the heat acclimatization period, to assess physiological and subjective changes. Rectal temperature, heart rate (HR), thermal discomfort at rest and at the end of exercise, rates of perceived exertion (RPE), and sweat loss and osmolality decreased following heat acclimatization in both groups. However, the decreases in the T group were larger than those in the NT group for HR at the end of exercise (−20 ± 13 vs. −13 ± 6 bpm, respectively, p = 0.044), thermal discomfort at rest (−2.6 ± 2.7 vs. −1.4 ± 2.1 cm, respectively, p = 0.013) and at the end of exercise (−2.6 ± 1.9 vs. −1.6 ± 1.7 cm, respectively, p = 0.037) and RPE (−2.3 ± 1.8 vs. −1.3 ± 1.7, respectively, p = 0.035). Thus, we showed that adding short (<60 min), daily, moderate-intensity training sessions during a professional mission in a hot and dry environment accelerated several heat-acclimatization-induced changes at rest and during exercise in only 5 days. PMID:28670286

The Role of Heat Tolerance Testing in Recovery and Return to Duty

DTIC Science & Technology

2008-10-01

CV diseases Hyperthyroidism Pheochromocytoma Infectious diseases Diabetes mellitus Psychiatric illness Parkinsonism Congenital abnormalities: CF...environments. To assess the heat tolerance status of prior heat stroke patient. Heat tolerance test (HTT) “HTT was effective in evaluating the heat tolerance

Female farmworkers' perceptions of heat-related illness and pregnancy health.

PubMed

Flocks, Joan; Vi Thien Mac, Valerie; Runkle, Jennifer; Tovar-Aguilar, Jose Antonio; Economos, Jeannie; McCauley, Linda A

2013-01-01

Although agricultural workers have elevated risks of heat-related illnesses (HRI), pregnant farmworkers exposed to extreme heat face additional health risk, including poor pregnancy health and birth outcomes. Qualitative data from five focus groups with 35 female Hispanic and Haitian nursery and fernery workers provide details about the women's perceptions of HRI and pregnancy. Participants believe that heat exposure can adversely affect general, pregnancy, and fetal health, yet feel they lack control over workplace conditions and that they lack training about these specific risks. These data are being used to develop culturally appropriate educational materials emphasizing health promoting and protective behaviors during pregnancy.

FEMALE FARMWORKERS’ PERCEPTIONS OF HEAT-RELATED ILLNESS AND PREGNANCY HEALTH

PubMed Central

Flocks, Joan; Mac, Valerie Vi Thien; Runkle, Jennifer; Tovar-Aguilar, Jose Antonio; Economos, Jeannie; McCauley, Linda A.

2017-01-01

While agricultural workers have elevated risks of heat-related illnesses (HRI), pregnant farmworkers exposed to extreme heat face additional health risk, including poor pregnancy health and birth outcomes. Qualitative data from five focus groups with 35 female Hispanic and Haitian nursery and fernery workers provide details about the women’s perceptions of HRI and pregnancy. Participants believe that heat exposure can adversely affect general, pregnancy, and fetal health, yet feel they lack control over workplace conditions and that they lack training about these specific risks. These data are being used to develop culturally appropriate educational materials emphasizing health promoting and protective behaviors during pregnancy. PMID:24125050

Heat-Related Illnesses

MedlinePlus Videos and Cool Tools

... Be Prepared Safe Citizen Day Organize Important Medical Information ER Checklists Preparing for Emergencies Be ready to ... anyone can be affected. Here you will find information about heat cramps and heat stroke and exhaustion. ...

Conjugate gradient heat bath for ill-conditioned actions.

PubMed

Ceriotti, Michele; Bussi, Giovanni; Parrinello, Michele

2007-08-01

We present a method for performing sampling from a Boltzmann distribution of an ill-conditioned quadratic action. This method is based on heat-bath thermalization along a set of conjugate directions, generated via a conjugate-gradient procedure. The resulting scheme outperforms local updates for matrices with very high condition number, since it avoids the slowing down of modes with lower eigenvalue, and has some advantages over the global heat-bath approach, compared to which it is more stable and allows for more freedom in devising case-specific optimizations.

Phosgene Poisoning Caused by the Use of Chemical Paint Removers Containing Methylene Chloride in Ill-Ventilated Rooms Heated by Kerosene Stoves

PubMed Central

Gerritsen, W. B.; Buschmann, C. H.

1960-01-01

Two cases resembling poisoning by phosgene following the use of a paint remover containing methylene chloride in ill-ventilated rooms heated by an oil stove are described. Experiments carried out under similar conditions demonstrated the production of phosgene in toxic concentrations. The potential hazards from non-inflammable solvents are discussed. PMID:13827592

Analysis of a Community-based Intervention to Reduce Heat-related Illness during Heat Waves in Licheng, China: a Quasi-experimental Study.

PubMed

Li, Jing; Xu, Xin; Wang, Jun; Zhao, Yun; Song, Xiu Ping; Liu, Zhi Dong; Cao, Li Na; Jiang, Bao Fa; Liu, Qi Yong

2016-11-01

To reduce health-related threats of heat waves, interventions have been implemented in many parts of the world. However, there is a lack of higher-level evidence concerning the intervention efficacy. This study aimed to determine the efficacy of an intervention to reduce the number of heat-related illnesses. A quasi-experimental design was employed by two cross-sectional surveys in the year 2014 and 2015, including 2,240 participants and 2,356 participants, respectively. Each survey was designed to include one control group and one intervention group, which conducted in Licheng, China. A representative sample was selected using a multistage sampling method. Data, collected from questionnaires about heat waves in 2014 and 2015, were analyzed using a difference-in-difference analysis and cost effectiveness analysis. Outcomes included changes in the prevalence of heat-related illnesses and cost-effectiveness variables. Relative to the control participants, the prevalence of heat-related illness in the intervention participants decreased to a greater extent in rural areas than in urban areas (OR=0.495 vs. OR=1.281). Moreover, the cost-effectiveness ratio in the intervention group was less than that in the control group (US$15.06 vs. US$15.69 per participant). Furthermore, to avoid one additional patient, the incremental cost-effectiveness ratio showed that an additional US$14.47 would be needed for the intervention compared to when no intervention was applied. The intervention program may be considered a worthwhile investment for rural areas that are more likely to experience heat waves. Meanwhile, corresponding improving measures should be presented towards urban areas. Future research should examine whether the intervention strategies could be spread out in other domestic or international regions where heat waves are usually experienced. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Summer outdoor temperature and occupational heat-related illnesses in Quebec (Canada)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adam-Poupart, Ariane; Smargiassi, Audrey; Institut national de santé publique du Québec

2014-10-15

Background: Predicted rise in global mean temperature and intensification of heat waves associated with climate change present an increasing challenge for occupational health and safety. Although important scientific knowledge has been gathered on the health effects of heat, very few studies have focused on quantifying the association between outdoor heat and mortality or morbidity among workers. Objective: To quantify the association between occupational heat-related illnesses and exposure to summer outdoor temperatures. Methods: We modeled 259 heat-related illnesses compensated by the Workers' Compensation Board of Quebec between May and September, from 1998 to 2010, with maximum daily summer outdoor temperatures inmore » 16 health regions of Quebec (Canada) using generalized linear models with negative binomial distributions, and estimated the pooled effect sizes for all regions combined, by sex and age groups, and for different time lags with random-effect models for meta-analyses. Results: The mean daily compensation count was 0.13 for all regions of Quebec combined. The relationship between daily counts of compensations and maximum daily temperatures was log-linear; the pooled incidence rate ratio (IRR) of daily heat-related compensations per 1 °C increase in daily maximum temperatures was 1.419 (95% CI 1.326 to 1.520). Associations were similar for men and women and by age groups. Increases in daily maximum temperatures at lags 1 and 2 and for two and three-day lag averages were also associated with increases in daily counts of compensations (IRRs of 1.206 to 1.471 for every 1 °C increase in temperature). Conclusion: This study is the first to quantify the association between occupational heat-related illnesses and exposure to summer temperatures in Canada. The model (risk function) developed in this study could be useful to improve the assessment of future impacts of predicted summer outdoor temperatures on workers and vulnerable groups, particularly in colder temperate zones. - Highlights: • 259 heat-related compensated illnesses were modeled with ambient temperature • An overall risk ratio of 1.419 (95% CI 1.326–1.520) for every 1 °C increase was found • Risk estimates were similar for men and women and by large age groups. • There were little lag effects (IRRs of 1.206 to 1.471 for every 1 °C increase)« less

Cost of preventing workplace heat-related illness through worker breaks and the benefit of climate-change mitigation

NASA Astrophysics Data System (ADS)

Takakura, Jun'ya; Fujimori, Shinichiro; Takahashi, Kiyoshi; Hijioka, Yasuaki; Hasegawa, Tomoko; Honda, Yasushi; Masui, Toshihiko

2017-06-01

The exposure of workers to hot environments is expected to increase as a result of climate change. In order to prevent heat-related illness, it is recommended that workers take breaks during working hours. However, this would lead to reductions in worktime and labor productivity. In this study, we estimate the economic cost of heat-related illness prevention through worker breaks associated with climate change under a wide range of climatic and socioeconomic conditions. We calculate the worktime reduction based on the recommendation of work/rest ratio and the estimated future wet bulb glove temperature, which is an index of heat stresses. Corresponding GDP losses (cost of heat-related illness prevention through worker breaks) are estimated using a computable general equilibrium model throughout this century. Under the highest emission scenario, GDP losses in 2100 will range from 2.6 to 4.0% compared to the current climate conditions. On the other hand, GDP losses will be less than 0.5% if the 2.0 °C goal is achieved. The benefit of climate-change mitigation for avoiding worktime loss is comparable to the cost of mitigation (cost of the greenhouse gas emission reduction) under the 2.0 °C goal. The relationship between the cost of heat-related illness prevention through worker breaks and global average temperature rise is approximately linear, and the difference in economic loss between the 1.5 °C goal and the 2.0 °C goal is expected to be approximately 0.3% of global GDP in 2100. Although climate mitigation and socioeconomic development can limit the vulnerable regions and sectors, particularly in developing countries, outdoor work is still expected to be affected. The effectiveness of some adaptation measures such as additional installation of air conditioning devices or shifting the time of day for working are also suggested. In order to reduce the economic impacts, adaptation measures should also be implemented as well as pursing ambitious climate change mitigation targets.

Proposed low-temperature solar engine

NASA Technical Reports Server (NTRS)

Peoples, J. A.; Kearns, G. B.

1976-01-01

Engine, proposed for conversion of Sun's heat to motion without need for heat pumps and associated equipment, uses expansion and contraction of aluminum rod to drive tow out-of-phase windlasses. Linear displacement of 0.076 cm in rod will exert sufficient force to drive pumps, generators, and compressors.

Hyperthermia: New Thoughts on an Old Problem.

ERIC Educational Resources Information Center

Hubbard, Roger W.; Armstrong, Lawrence E.

1989-01-01

Reviews causes and treatment of heat syncope, heat exhaustion, and exertional heatstroke and discusses the effectiveness of cooling heatstroke victims in ice versus cooled water. Cooled water appears to be as effective, though ice water decreases the incidence of cardiovascular complications. An energy depletion model is presented. (Author/SM)

A Cross-Sectional Study of Heat Wave-Related Knowledge, Attitude, and Practice among the Public in the Licheng District of Jinan City, China

PubMed Central

Li, Jing; Xu, Xin; Ding, Guoyong; Zhao, Yun; Zhao, Ruixia; Xue, Fuzhong; Li, Jing; Gao, Jinghong; Yang, Jun; Jiang, Baofa; Liu, Qiyong

2016-01-01

Knowledge, attitude, and practice (KAP) are three key components for reducing the adverse health impacts of heat waves. However, research in eastern China regarding this is scarce. The present study aimed to evaluate the heat wave-related KAP of a population in Licheng in northeast China. This cross-sectional study included 2241 participants. Data regarding demographic characteristics, KAP, and heat illnesses were collected using a structured questionnaire. Univariate analysis and unconditional logistic regression models were used to analyze the data. Most residents had high KAP scores, with a mean score of 12.23 (standard deviation = 2.23) on a 17-point scale. Urban women and participants aged 35–44 years had relatively high total scores, and those with high education levels had the highest total score. There was an increased risk of heat-related illness among those with knowledge scores of 3–5 on an 8-point scale with mean score of 5.40 (standard deviation = 1.45). Having a positive attitude toward sunstroke prevention and engaging in more preventive practices to avoid heat exposure had a protective interaction effect on reducing the prevalence of heat-related illnesses. Although the KAP scores were relatively high, knowledge and practice were lacking to some extent. Therefore, governments should further develop risk-awareness strategies that increase awareness and knowledge regarding the adverse health impact of heat and help in planning response strategies to improve the ability of individuals to cope with heat waves. PMID:27367715

Update: Exertional rhabdomyolysis, active component, U.S. Army, Navy, Air Force, and Marine Corps, 2011-2015.

PubMed

Armed Forces Health Surveillance Branch

2016-03-01

Among active component members of the U.S. Army, Navy, Air Force, and Marine Corps in 2015, there were 456 incident episodes of rhabdomyolysis likely due to physical exertion or heat stress ("exertional rhabdomyolysis"). Annual rates of incident diagnoses of exertional rhabdomyolysis increased 17% between 2014 and 2015. In 2015, the highest incidence rates occurred in service members who were male; younger than 20 years of age; black, non-Hispanic; members of the Marine Corps and Army; recruit trainees; and in combat-specific occupations. Most cases of exertional rhabdomyolysis were diagnosed at installations that support basic combat/recruit training or major ground combat units of the Army or Marine Corps. Medical care providers should consider exertional rhabdomyolysis in the differential diagnosis when service members (particularly recruits) present with muscular pain and swelling, limited range of motion, or the excretion of dark urine (e.g., myoglobinuria) after strenuous physical activity, particularly in hot, humid weather.

Time-of-day effects of exposure to solar radiation on thermoregulation during outdoor exercise in the heat.

PubMed

Otani, Hidenori; Goto, Takayuki; Goto, Heita; Shirato, Minayuki

2017-01-01

High solar radiation has been recognised as a contributing factor to exertional heat-related illness in individuals exercising outdoors in the heat. Although solar radiation intensity has been known to have similar time-of-day variation as body temperature, the relationship between fluctuations in solar radiation associated with diurnal change in the angle of sunlight and thermoregulatory responses in individuals exercising outdoors in a hot environment remains largely unknown. The present study therefore investigated the time-of-day effects of variations in solar radiation associated with changing solar elevation angle on thermoregulatory responses during moderate-intensity outdoor exercise in the heat of summer. Eight healthy, high school baseball players, heat-acclimatised male volunteers completed a 3-h outdoor baseball trainings under the clear sky in the heat. The trainings were commenced at 0900 h in AM trial and at 1600 h in PM trial each on a separate day. Solar radiation and solar elevation angle during exercise continued to increase in AM (672-1107 W/m 2 and 44-69°) and decrease in PM (717-0 W/m 2 and 34-0°) and were higher on AM than on PM (both P < 0.001). Although ambient temperature (AM 32-36°C, PM 36-30°C) and wet-bulb globe temperature (AM 31-33°C, PM 34-27°C) also continued to increase in AM and decrease in PM, there were no differences between trials in these (both P > 0.05). Tympanic temperature measured by an infrared tympanic thermometer and mean skin temperature were higher in AM than PM at 120 and 180 min (P < 0.05). Skin temperature was higher in AM than PM at the upper arm and thigh at 120 min (P < 0.05) and at the calf at 120 and 180 min (both P < 0.05). Body heat gain from the sun was greater during exercise in AM than PM (P < 0.0001), at 0-60 min in PM than AM (P < 0.0001) and at 120-180 min in AM than PM (P < 0.0001). Dry heat loss during exercise was greater at 0-60 min (P < 0.0001), and lower at 60-120 min (P < 0.05) and 120-180 min (P < 0.0001) in AM than PM. Evaporative heat loss during exercise was greater in PM than AM at 120-180 min (P < 0.0001). Total (dry + evaporation) heat loss at the skin was greater during exercise in PM than AM (P < 0.0001), at 0-60 min in AM than PM (P < 0.0001) and at 60-120 and 120-180 min in PM than AM (P < 0.05 and 0.0001). Heart rate at 120-150 min was also higher in AM than PM (P < 0.05). Neither perceived thermal sensation nor rating of perceived exertion was different between trials (both P > 0.05). The current study demonstrates a greater thermoregulatory strain in the morning than in the afternoon resulting from a higher body temperature and heart rate in relation to an increase in environmental heat stress with rising solar radiation and solar elevation angle during moderate-intensity outdoor exercise in the heat. This response is associated with a lesser net heat loss at the skin and a greater body heat gain from the sun in the morning compared with the afternoon.

Working safely in summertime heat

Treesearch

Robert B. Rummer

1997-01-01

As logging operations continue in the hotter months of he year, the safety hazard of heat stress appears. Loggers are particularly at risk, because the combination of hard physical work and outdoor conditions puts high demands on the body. While loggers rarely die from heat stress, they may suffer heat illness symptoms ranging from the discomfort of heat rash to nausea...

A field study of the effectiveness and practicality of a novel hybrid personal cooling vest worn during rest in Hong Kong construction industry.

PubMed

Chan, Albert P C; Zhang, Ying; Wang, Faming; Wong, Francis F K; Chan, Daniel W M

2017-12-01

A novel hybrid cooling vest (HCV) incorporated with phase change materials (PCMs) and ventilation fans has been developed for construction workers in Hong Kong to attenuate heat stress and prevent heat-related illnesses, and its effectiveness and practicality have been validated in this study. A total of 140 wear trials involving of 140 workers were conducted in Hong Kong construction sites during the summer time. Each wear trial involves a two-day wear test, of which one day workers wore the HCV (denoted as VEST) during resting, and another day they wore traditional workwear (denoted as CON). Subjects were asked to rate their perceived exertion (RPE), thermal sensations (TS) and 7 other subjective attributes. There were significant differences in the effectiveness on reducing workers' heat strain between VEST and CON in terms of alleviations of heart rate (ΔHR), ΔTS, ΔRPE as well as ΔPeSI (p < 0.001). The practicality of HCV is evidenced by a significant improvement by 0.93-1.34 on the rating scores of perceived cooling effect, sensations of comfort and skin dryness during rest and fatigue recovery in VEST at the level of 0.05, and high ratings of 4.85-5 (rating scale from 1 to 7, and the higher the better) by subjects on the preference, fitness as well as effectiveness to combat heat stress. In addition, a remarkable proportion of 91 per cent of subjects prefer to use this newly designed HCV as a cooling measure during rest. The power to alleviate perceptual heat stain (PeSA) in VEST is about twice of that by rest, which means HCV can notably improve the workers' perceptual heat strain in a limited resting duration. However, the strain alleviation power of HCV nearly remains unchanged with the prolonged rest duration. Thus, the optimal work-rest schedule needs to be investigated in a further study. Copyright © 2017 Elsevier Ltd. All rights reserved.

A cross-sectional, randomized cluster sample survey of household vulnerability to extreme heat among slum dwellers in ahmedabad, india.

PubMed

Tran, Kathy V; Azhar, Gulrez S; Nair, Rajesh; Knowlton, Kim; Jaiswal, Anjali; Sheffield, Perry; Mavalankar, Dileep; Hess, Jeremy

2013-06-18

Extreme heat is a significant public health concern in India; extreme heat hazards are projected to increase in frequency and severity with climate change. Few of the factors driving population heat vulnerability are documented, though poverty is a presumed risk factor. To facilitate public health preparedness, an assessment of factors affecting vulnerability among slum dwellers was conducted in summer 2011 in Ahmedabad, Gujarat, India. Indicators of heat exposure, susceptibility to heat illness, and adaptive capacity, all of which feed into heat vulnerability, was assessed through a cross-sectional household survey using randomized multistage cluster sampling. Associations between heat-related morbidity and vulnerability factors were identified using multivariate logistic regression with generalized estimating equations to account for clustering effects. Age, preexisting medical conditions, work location, and access to health information and resources were associated with self-reported heat illness. Several of these variables were unique to this study. As sociodemographics, occupational heat exposure, and access to resources were shown to increase vulnerability, future interventions (e.g., health education) might target specific populations among Ahmedabad urban slum dwellers to reduce vulnerability to extreme heat. Surveillance and evaluations of future interventions may also be worthwhile.

The effect of firefighter protective garments, self-contained breathing apparatus and exertion in the heat on postural sway.

PubMed

White, Scott C; Hostler, David

2017-08-01

Fire suppression wearing thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) challenges a firefighter's balance and may explain firefighter falls. Postural control based on force plate centre of pressure (COP) was compared for healthy subjects wearing TPC and SCBA before and after 20 min of heavy physical exertion in hot conditions. Baseline measures with and without TPC and SCBA (two different SCBA cylinder masses) were compared before and after exertion that included elements of fire suppression activities in an environmental chamber. COP excursion and variability increased with exertion for TPC and SCBA conditions compared to non-stressed conditions. The two different cylinder masses had no significant effect. Wearing TPC and SCBA when physically stressed in a hot environment increases postural sway and exacerbates postural control. Subjects compensated for the extra mass and adjusted to control postural sway with the addition of TPC and SCBA, but the stress protocol amplified these adjustments. Practitioner Summary: Firefighters wear thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) when heat-stressed and fatigued. Wearing TPC and SCBA was found to negatively impact balance when stressed, but not for non-stressed or two different sized SCBA tanks. Simulating fire-ground conditions wearing TPC and SCBA should be considered for improving balance.

Core body temperature during competition in the heat: National Boys' 14s Junior Championships.

PubMed

Bergeron, Michael F; McLeod, Kathryn S; Coyle, John F

2007-11-01

To examine on-court core body temperature (T(C)) and sweat loss, as well as pre- and post-play hydration status, in elite adolescent tennis players during a national championships event in a hot climate. Eight healthy, fit, young male tennis players (mean (SD) age 13.9 (0.9) years; mass 56.0 (10.7) kg; height 169.2 (14.7) cm) were evaluated during first-round singles competition at the National Boys' 14s Junior Championships in the heat (wet-bulb globe temperature (WBGT) 29.6 (0.4) degrees C). Five of those same players were also evaluated during a same-day doubles match (WBGT 31.3 (0.5) degrees C). During doubles (4.37 (0.35) h after singles), pre-play urine specific gravity (USG) (1.025 (0.002); p = 0.06) and total sweat loss (1.9 (0.2) litres; p = 0.10) tended to be higher before and during doubles, respectively, compared to singles. However, percentage change in body mass (-0.5 (0.3) %) tended to be comparatively less (p = 0.08), even though the doubles matches were generally longer (106.6 (11.2) vs 78.8 (10.9) min; p = 0.09) and the degree minutes total was greater (p = 0.04). T(C) increased (p<0.001) during singles and remained elevated, even after 10 min following the end of play. Notably, pre-play (singles) USG was strongly associated (p = 0.005) with the players' final T(C) (38.7 (0.3) degrees C) recorded at the end of singles play. Junior tennis players who begin a match not well hydrated could have progressively increasing thermal strain and a greater risk for exertional heat illness as the match advances.

Effects of radiant heat exposure on pacing pattern during a 15-km cycling time trial.

PubMed

Levels, Koen; de Koning, Jos; Broekhuijzen, Iris; Zwaan, Tamara; Foster, Carl; Daanen, Hein

2014-01-01

The goal of this study was to investigate the effects of different durations of skin temperature manipulation on pacing patterns and performance during a 15-km cycling time trial. Nineteen well-trained men completed three 15-km cycling time trials in 18 °C and 50% relative humidity with 4.5-km (short-heat), 9.0-km (long-heat) or without (control) radiant heat exposure applied by infrared heaters after 1.5 km in the time trial. During the time trials, power output, mean skin temperature, rectal temperature, heart rate and rating of perceived exertion were assessed. The radiant heat exposure resulted in higher mean skin temperature during the time trial for short-heat (35.0 ± 0.6 °C) and long-heat (35.3 ± 0.5 °C) than for control (32.5 ± 1.0 °C; P < 0.001), whereas rectal temperature was similar (P = 0.55). The mean power output was less for short-heat (273 ± 8 W; P = 0.001) and long-heat (271 ± 9 W; P = 0.02) than for control (287 ± 7 W), but pacing patterns did not differ (P = 0.55). Heart rate was greatest in control (177 ± 9 beats · min(-1); P < 0.001), whereas the rating of perceived exertion remained similar. We concluded that a radiant heat exposure and associated higher skin temperature reduced overall performance, but did not modify pacing pattern during a 15-km cycling time trial, regardless of the duration of the exposure.

Chronic Fatigue Syndrome versus Systemic Exertion Intolerance Disease

PubMed Central

Jason, Leonard A.; Sunnquist, Madison; Brown, Abigail; Newton, Julia L.; Strand, Elin Bolle; Vernon, Suzanne D.

2015-01-01

Background The Institute of Medicine has recommended a change in the name and criteria for Chronic Fatigue Syndrome (CFS), renaming the illness Systemic Exertion Intolerance Disease (SEID). The new SEID case definition requires substantial reductions or impairments in the ability to engage in pre-illness activities, unrefreshing sleep, post-exertional malaise, and either cognitive impairment or orthostatic intolerance. Purpose In the current study, samples were generated through several different methods and were used to compare this new case definition to previous case definitions for CFS, Myalgic Encephalomyelitis (ME-ICC), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), as well as a case definition developed through empirical methods. Methods We used a cross-sectional design with samples from tertiary care settings, a biobank sample, and other forums. 796 patients from the US, Great Britain, and Norway completed the DePaul Symptom Questionnaire. Results Findings indicated that the SEID criteria identified 88% of participants in the samples analyzed, which is comparable to the 92% that met the Fukuda criteria. The SEID case definition was compared to a four item empiric criteria, and findings indicated that the four item empiric criteria identified a smaller, more functionally limited and symptomatic group of patients. Conclusion The recently developed SEID criteria appears to identify a group comparable in size to the Fukuda et al. criteria, but a larger group of patients than the Canadian ME/CFS and ME criteria, and selects more patients who have less impairment and fewer symptoms than a four item empiric criteria. PMID:26345409

Assessing Heat Stress and Health among Construction Workers in a Changing Climate: A Review

PubMed Central

Acharya, Payel; Boggess, Bethany

2018-01-01

Construction workers are at an elevated risk of heat stress, due to the strenuous nature of the work, high temperature work condition, and a changing climate. An increasing number of workers are at risk, as the industry’s growth has been fueled by high demand and vast numbers of immigrant workers entering into the U.S., the Middle East and Asia to meet the demand. The risk of heat-related illnesses is increased by the fact that little to no regulations are present and/or enforced to protect these workers. This review recognizes the issues by summarizing epidemiological studies both in the U.S. and internationally. These studies have assessed the severity with which construction workers are affected by heat stress, risk factors and co-morbidities associated with heat-related illnesses in the construction industry, vulnerable populations, and efforts in implementing preventive measures. PMID:29389908

Seizures

MedlinePlus

... of seizures. Some have mild symptoms without shaking. Considerations It may be hard to tell if someone ... Epilepsy Fever (particularly in young children ) Head injury Heart disease Heat illness ( heat intolerance ) High fever Phenylketonuria ( PKU ), ...

The Tayside infant morbidity and mortality study: effect on health of using gas for cooking.

PubMed Central

Ogston, S A; Florey, C D; Walker, C H

1985-01-01

The relation between respiratory illness and the use of gas for cooking was examined from data on 1565 infants born to mothers who were primigravidas living in Dundee in 1980. Episodes of, and admissions to hospital for, respiratory illness were recorded during the first year of life. Both admissions and episodes were more common in infants from families using gas for cooking or heating than in infants from families using any other type of cooking or heating, but the differences were not significant. Results from this and other studies show that there is probably a small relation between respiratory illness and the use of gas appliances without a flue. To show convincingly whether such a relation exists might require a survey of 18 000-23 000 subjects. Respiratory illness was, however, strongly and positively related to parental smoking, a finding that is often made even in small studies. PMID:3919868

Monitoring stress and recovery: new insights for the prevention of injuries and illnesses in elite youth soccer players.

PubMed

Brink, Michel S; Visscher, Chris; Arends, Suzanne; Zwerver, Johannes; Post, Wendy J; Lemmink, Koen Apm

2010-09-01

Elite youth soccer players have a relatively high risk for injuries and illnesses due to increased physical and psychosocial stress. The aim of this study is to investigate how measures to monitor stress and recovery, and its analysis, provide useful information for the prevention of injuries and illnesses in elite youth soccer players. 53 elite soccer players between 15 and 18 years of age participated in this study. To determine physical stress, soccer players registered training and match duration and session rating of perceived exertion for two competitive seasons by means of daily training logs. The Dutch version of the Recovery Stress Questionnaire for athletes (RESTQ-Sport) was administered monthly to assess the psychosocial stress-recovery state of players. The medical staff collected injury and illness data using the standardised Fédération Internationale de Football Association registration system. ORs and 95% CIs were calculated for injuries and illnesses using multinomial regression analyses. The independent measures were stress and recovery. During the study period, 320 injuries and 82 illnesses occurred. Multinomial regression demonstrated that physical stress was related to both injury and illness (range OR 1.01 to 2.59). Psychosocial stress and recovery were related the occurrence of illness (range OR 0.56 to 2.27). Injuries are related to physical stress. Physical stress and psychosocial stress and recovery are important in relation to illness. Individual monitoring of stress and recovery may provide useful information to prevent soccer players from injuries and illnesses.

Heat-related illness in Washington State agriculture and forestry sectors.

PubMed

Spector, June T; Krenz, Jennifer; Rauser, Edmund; Bonauto, David K

2014-08-01

We sought to describe heat-related illness (HRI) in agriculture and forestry workers in Washington State. Demographic and clinical Washington State Fund workers' compensation agriculture and forestry HRI claims data (1995-2009) and Washington Agriculture Heat Rule citations (2009-2012) were accessed and described. Maximum daily temperature (Tmax) and Heat Index (HImax) were estimated by claim date and location using AgWeatherNet's weather station network. There were 84 Washington State Fund agriculture and forestry HRI claims and 60 Heat Rule citations during the study period. HRI claims and citations were most common in crop production and support subsectors. The mean Tmax (HImax) was 95°F (99°F) for outdoor HRI claims. Potential HRI risk factors and HRI-related injuries were documented for some claims. Agriculture and forestry HRI cases are characterized by potential work-related, environmental, and personal risk factors. Further work is needed to elucidate the relationship between heat exposure and occupational injuries. © 2014 Wiley Periodicals, Inc.

Heat-Related Illness in Washington State Agriculture and Forestry Sectors

PubMed Central

Spector, June T.; Krenz, Jennifer; Rauser, Edmund; Bonauto, David K.

2017-01-01

Background We sought to describe heat-related illness (HRI) in agriculture and forestry workers in Washington State. Methods Demographic and clinical Washington State Fund workers’ compensation agriculture and forestry HRI claims data (1995–2009) and Washington Agriculture Heat Rule citations (2009–2012) were accessed and described. Maximum daily temperature (Tmax) and Heat Index (HImax) were estimated by claim date and location using AgWeatherNet’s weather station network. Results There were 84 Washington State Fund agriculture and forestry HRI claims and 60 Heat Rule citations during the study period. HRI claims and citations were most common in crop production and support subsectors. The mean Tmax (HImax) was 95°F (99°F) for outdoor HRI claims. Potential HRI risk factors and HRI-related injuries were documented for some claims. Conclusions Agriculture and forestry HRI cases are characterized by potential work-related, environmental, and personal risk factors. Further work is needed to elucidate the relationship between heat exposure and occupational injuries. PMID:24953344

Parents' and Coaches' Guide to Dehydration and Other Heat Illnesses in Children

MedlinePlus

... illnesses can be prevented and successfully treated. Children sweat less than adults. This makes it harder for ... they do not replace body fluids lost by sweating. Being even a little dehydrated can make a ...

From agricultural fields to urban asphalt: the role of worker education to promote California's heat illness prevention standard.

PubMed

Riley, Kevin; Delp, Linda; Cornelio, Deogracia; Jacobs, Sarah

2012-01-01

This article describes an innovative approach to reach and educate workers and worker advocates about California's outdoor heat illness prevention standard. In 2010, Cal/OSHA initiated a statewide education campaign to reduce heat-related illnesses and fatalities and increase awareness of the standard's requirements. In Southern California, the UCLA Labor Occupational Safety and Health Program (LOSH) focused on three principal strategies of community-based outreach, popular education, and organizational capacity building. Central to the LOSH approach was the integration of health promotores into core program planning and training activities and the expansion of campaign activities to a wide variety of rural and urban workers. We describe each of these strategies and analyze the possibilities and constraints of worker education to support implementation of this standard, particularly given the vulnerabilities of the impacted workforce, the often precarious nature of employment arrangements for these workers, and the resource limitations of Cal/OSHA.

Update: Exertional rhabdomyolysis, active component, U.S. Armed Forces, 2012-2016.

PubMed

2017-03-01

Among active component service members in 2016, there were 525 incident diagnoses of rhabdomyolysis likely due to physical exertion and/or heat stress ("exertional rhabdomyolysis"). The crude incidence rate in 2016 was 40.7 cases per 100,000 person-years. Annual rates of incident diagnoses of exertional rhabdomyolysis increased 46.2% between 2013 and 2016, with the greatest percentage change occurring between 2014 and 2015. In 2016, relative to their respective counterparts, the highest incidence rates of exertional rhabdomyolysis affected service members who were male; younger than 20 years of age; and black, non-Hispanic. During the surveillance period, annual incidence rates were highest among service members of the Marine Corps, intermediate among those in the Army, and lowest among those in the Air Force and Navy. Most cases of exertional rhabdomyolysis were diagnosed at installations that support basic combat/recruit training or major ground combat units of the Army or the Marine Corps. Medical care providers should consider exertional rhabdomyolysis in the differential diagnosis when service members (particularly recruits) present with muscular pain or swelling, limited range of motion, or the excretion of dark urine (possibly due to myoglobinuria) after strenuous physical activity, particularly in hot, humid weather.

Thermal effects on fish ecology

USGS Publications Warehouse

Coutant, Charles C.

1976-01-01

Of all the environmental factors that influence aquatic organisms, temperature is the most all-pervasive. There is always an environmental temperature while other factors may or may not be present to exert their effects. Fish are, for all practical purposes, thermal conformers, or obligate poikilotherms. That is, they are able to exert little significant influence on maintaining a certain body temperature by specialized metabolic or behavioral means. Their body temperature thus fluctuates nearly in concert with the temperature of their aquatic medium (although particularly large, actively-moving fish such as tuna have deep muscle temperatures slightly higher than the water). Intimate contact at the gills of body fluids with the outside water and the high specific heat of water provide a very efficient heat exchanger that insures this near identity of internal and external temperatures.

Heat stress management program improving worker health and operational effectiveness: a case study.

PubMed

Huss, Rosalyn G; Skelton, Scott B; Alvis, Kimberly L; Shane, Leigh A

2013-03-01

Heat stress monitoring is a vital component of an effective health and safety program when employees work in exceptionally warm environments. Workers at hazardous waste sites often wear personal protective equipment (PPE), which increases the body heat stress load. No specific Occupational Safety and Health Administration (OSHA) regulations address heat stress; however, OSHA does provide several guidance documents to assist employers in addressing this serious workplace health hazard. This article describes a heat stress and surveillance plan implemented at a hazardous waste site as part of the overall health and safety program. The PPE requirement for work at this site, coupled with extreme environmental temperatures, made heat stress a significant concern. Occupational health nurses and industrial hygienists developed a monitoring program for heat stress designed to prevent the occurrence of significant heat-related illness in site workers. The program included worker education on the signs of heat-related illness and continuous physiologic monitoring to detect early signs of heat-related health problems. Biological monitoring data were collected before workers entered the exclusion zone and on exiting the zone following decontamination. Sixty-six site workers were monitored throughout site remediation. More than 1,700 biological monitoring data points were recorded. Outcomes included improved worker health and safety, and increased operational effectiveness. Copyright 2013, SLACK Incorporated.

Understanding of flux-limited behaviors of heat transport in nonlinear regime

NASA Astrophysics Data System (ADS)

Guo, Yangyu; Jou, David; Wang, Moran

2016-01-01

The classical Fourier's law of heat transport breaks down in highly nonequilibrium situations as in nanoscale heat transport, where nonlinear effects become important. The present work is aimed at exploring the flux-limited behaviors based on a categorization of existing nonlinear heat transport models in terms of their theoretical foundations. Different saturation heat fluxes are obtained, whereas the same qualitative variation trend of heat flux versus exerted temperature gradient is got in diverse nonlinear models. The phonon hydrodynamic model is proposed to act as a standard to evaluate other heat flux limiters because of its more rigorous physical foundation. A deeper knowledge is thus achieved about the phenomenological generalized heat transport models. The present work provides deeper understanding and accurate modeling of nonlocal and nonlinear heat transport beyond the diffusive limit.

Emergency Procedures for the Strength and Conditioning Coach.

ERIC Educational Resources Information Center

Binkley, Helen M.; Williams, Lauren C.

2003-01-01

Presents suggested actions for strength and conditioning coaches to take when an emergency arises, focusing on: athlete collapse; thermoregulatory conditions (heat illness and cold illness and their prevention); asthma/bronchospasm and prevention of asthma/bronchospasm emergencies; diabetes and prevention of diabetic emergencies; and…

The force exerted by a fireball

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makrinich, G.; Fruchtman, A.

The force exerted by a fireball was deduced both from the change of the equilibrium position of a pendulum and from the change in the pendulum oscillation period. That measured force was found to be several times larger than the force exerted by the ions accelerated across the double layer that is assumed to surround the fireball. The force enhancement that is expected by ion-neutral collisions in the fireball is evaluated to be too small to explain the measured enhanced force. Gas pressure increase, due to gas heating through electron-neutral collisions, as recently suggested [Stenzel et al., J. Appl. Phys.more » 109, 113305 (2011)], is examined as the source for the force enhancement.« less

Effectiveness of cold water immersion for treating exertional heat stress when immediate response is not possible.

PubMed

Flouris, A D; Friesen, B J; Carlson, M J; Casa, D J; Kenny, G P

2015-06-01

Immediate treatment with cold water immersion (CWI) is the gold standard for exertional heatstroke. In the field, however, treatment is often delayed due to delayed paramedic response and/or inaccurate diagnosis. We examined the effect of treatment (reduction of rectal temperature to 37.5 °C) delays of 5, 20, and 40 min on core cooling rates in eight exertionally heat-stressed (40.0 °C rectal temperature) individuals. We found that rectal temperature was elevated above baseline (P < 0.05) at the end of all delay periods (5 min: 40.08 ± 0.32; 20 min: 39.92 ± 0.40; 40 min: 39.57 ± 0.29 °C). Mean arterial pressure was reduced (P < 0.05) below baseline (92 ± 1.8 mm Hg) after all delay periods (5 min: 75 ± 2.6; 20 min: 74 ± 1.7; 40 min: 70 ± 2.1 mm Hg; P > 0.05). Rectal core cooling rates were similar among conditions (5 min: 0.20 ± 0.01; 20 min: 0.17 ± 0.02; 40 min: 0.17 ± 0.01 °C/min; P > 0.05). The rectal temperature afterdrop following CWI was similar across conditions (5 min: 35.95; 20 min: 35.61; 40 min: 35.87 °C; P > 0.05). We conclude that the effectiveness of 2 °C CWI as a treatment for exertional heat stress remains high even when applied with a delay of 40 min. Therefore, our results support that CWI is the most appropriate treatment for exertional heatstroke as it is capable of quickly reversing hyperthermia even when treatment is commenced with a significant delay. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Fatal heat stroke in children found in parked cars: autopsy findings.

PubMed

Adato, Berliz; Dubnov-Raz, Gal; Gips, Hadas; Heled, Yuval; Epstein, Yoram

2016-09-01

A common and unfortunate cause for heat stroke-related deaths in children is entrapment in closed vehicles. The aim of this study was to analyze the pathological consequences of such grave events. Autopsy reports of all children that were brought to a national forensic medicine center after being found dead in closed vehicles over a 21-year period (1995-2015) were reviewed. Data extracted were the circumstances of the events, child age, sex, height and weight, time, date and duration of entrapment, and environmental temperatures at the time of entrapment and the autopsy findings. Eight deceased children were brought to the forensic medicine center for autopsy, and seven families consented to the procedure. Autopsy findings included diffuse petechiae and hemorrhages of serosal membranes (n = 7/7) and lung congestion (n = 3/7). Typical autopsy findings following classical heat stroke in children include diffuse petechiae and hemorrhages and lung involvement. These findings are similar to those reported in adults that had died following exertional heat stroke-a very different mechanism of heat accumulation. Prevention of future events can possibly be obtained by public education on the rapid heating of closed vehicles, the vulnerability of children to heat, and the caregiver role in child entrapment. • A common and unfortunate cause for heat stroke-related deaths in children is entrapment in closed vehicles. The pathological consequences of such grave events have not been previously reported. What is New: • This study is the first to describe autopsy findings from children who were found dead in parked cars. • Autopsy findings included diffuse petechiae hemorrhages of serosal membranes and lung congestion. • These findings are identical to those seen in adults following exertional heat stroke.

Differences in ME and CFS Symptomology in Patients with Normal and Abnormal Exercise Test Results.

PubMed

McManimen, Stephanie L; Jason, Leonard A

2017-01-01

Post-exertional malaise (PEM) is a cardinal symptom of myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS), which often distinguishes patients with this illness from healthy controls or individuals with exclusionary illnesses such as depression. However, occurrence rates for PEM fluctuate from subject to how the symptom is operationalized. One commonly utilized method is exercise testing, maximal or submaximal. Many patients with ME and CFS experience PEM after participating in these tests, and often show abnormal results. However, some patients still exhibit normal results after participating in the exercise testing. This study examined the differences between two patient groups with ME and CFS, those with normal results and those with abnormal results, on several PEM-related symptoms and illness characteristics. The results suggest those that displayed abnormal results following testing have more frequent and severe PEM, worse overall functioning, and are more likely to be bedbound than those that displayed normal results.

Housing conditions, respiratory illness, and lung function in children in South Wales.

PubMed Central

Yarnell, J W; St Leger, A S

1977-01-01

The hypothesis was tested that respiratory illness in children occurs more commonly in old housing than in housing built to modern standards. Three areas of housing were chosen in a South Wales valley: a recently constructed council estate with district central heating; a modern council estate heated with open coal fires; and an area of much older, traditional valley housing. Mothers reported the greatest proportion of children free of colds and sore throats during the previous 12 months in the area of traditional valley housing; mothers of children in the centrally heated estate reported the least proportion of children free of colds. Children's lung function was best in the area of traditional valley housing and worst in the centrally heated council estate. Data on demographic indices and respiratory morbidity suggest that the inhabitants of the two council estates have comparable characteristics. Another hypothesis which may explain the findings is proposed. PMID:588858

Marginal effects of a large caffeine dose on heat balance during exercise-heat stress.

PubMed

Ely, Brett R; Ely, Matthew R; Cheuvront, Samuel N

2011-02-01

The use of caffeine supplements in athletic and military populations has increased in recent years. Excessive caffeine consumption in conjunction with exercise in a hot environment may predispose individuals to heat illness. To examine heat balance induced by a large dose of caffeine during exercise in a hot environment. Ten men, not heat acclimated and not habitual caffeine users, consumed either caffeine (CAF; 9 mg/kg) or placebo (PLA) before performing cycle-ergometer exercise for 30 min at 50% VO2peak in a 40 °C, 25% relative humidity environment while body temperature (core and skin) and ratings of thermal comfort (TC) were monitored. Heat-exchange variables were calculated using partitional calorimetry and thermometry. Mean body temperature (Tb) was higher (p < .05) with CAF (37.18 ± 0.15 °C) than with PLA (36.93 ± 0.15 °C) at the start of exercise. Heat production was slightly higher (~8 W, p < .05) with CAF. There were no differences in heat storage, dry heat gains, TC, or Tb during exercise. A caffeine dose of 9 mg/kg does not appreciably alter heat balance during work in a hot environment. The small increase in Tb observed with CAF was undetected by the participants and is unlikely to increase physiological strain sufficiently to affect endurance performance or risk of heat illness.

Dehydration, Heat Stroke, or Hyponatremia? The Recognition, Treatment, and Prevention of Hyponatremia Caused by High Exercise Outdoor Activities.

ERIC Educational Resources Information Center

Cochran, Brent

Hyponatremia (severe sodium depletion) has symptoms similar to heat exhaustion and heat stroke and can easily be misdiagnosed. The number of wilderness users and extreme adventure activities has increased in recent years, and more cases are being diagnosed. Given that a 1993 study found that 1 in 10 cases of heat-related illnesses were…

Does biological sex impact intestinal epithelial injury, small intestine permeability, gastrointestinal symptoms and systemic cytokine profile in response to exertional-heat stress?

PubMed

Snipe, Rhiannon M J; Costa, Ricardo J S

2018-05-23

This study aimed to determine the influence of biological sex on intestinal injury, permeability, gastrointestinal symptoms, and systemic cytokine profile in response to exertional-heat stress. Male (n= 13) and eumenorrheic female (n= 11) endurance runners completed 2 h running at 60% V̇O 2max in 35°C. Blood samples were collected pre- and post-exercise and during recovery to determine plasma intestinal fatty-acid binding protein (I-FABP) and systemic cytokine profile. Urinary lactulose:L-rhamnose ratio was used to determine small intestine permeability. I-FABP increased 479% pre- to post-exercise (p< 0.001), with no difference between sexes (p= 0.432). No differences between sexes were observed for small intestine permeability (p= 0.808), gut discomfort, total, upper- and lower-gastrointestinal symptoms. However, males reported significantly higher flatulence (p= 0.049) and abdominal stitch (p= 0.025) compared to females. IL-6, IL-8, IL-10 and IL-1ra increased pre- to post-exercise (p< 0.05), with no difference between sexes. However, IL-1β increased post-exercise in males only, and was higher in males compared to females (p= 0.044). Findings suggest that when females are in the follicular phase of the menstrual cycle, biological sex has no effect on intestinal epithelial injury and permeability, and minimal effect on gastrointestinal symptoms and systemic cytokine profile in response to exertional-heat stress.

Use of Biomarkers to Optimize Heat Acclimation in Women

DTIC Science & Technology

1996-10-01

that synthesis of HSP72 was induced in lymphocytes, spleen cells and soleus muscle after 20 min of exercise while rectal temperature elevated above 40...lethal temperatures for death due to nonexertionally and exertionally induced heat exhaustion, respectively (15). Upon completion of the exercise ...During exercise , interstitial fluid levels are reduced due to sweat formation and fluid shifts which tend to induce hypovolemia, compromising

Dynamical friction on hot bodies in opaque, gaseous media

NASA Astrophysics Data System (ADS)

Masset, Frédéric S.; Velasco Romero, David A.

2017-03-01

We consider the gravitational force exerted on a point-like perturber of mass M travelling within a uniform gaseous, opaque medium at constant velocity V. The perturber irradiates the surrounding gas with luminosity L. The diffusion of the heat released is modelled with a uniform thermal diffusivity χ. Using linear perturbation theory, we show that the force exerted by the perturbed gas on the perturber differs from the force without radiation (or standard dynamical friction). Hot, underdense gas trails the mass, which gives rise to a new force component, the heating force, with direction +V, thus opposed to the standard dynamical friction. In the limit of low Mach numbers, the heating force has expression F_heat=γ (γ -1)GML/(2χ c_s^2), cs being the sound speed and γ the ratio of specific heats. In the limit of large Mach numbers, Fheat = (γ - 1)GML/(χV2)f(rminV/4χ), where f is a function that diverges logarithmically as rmin tends to zero. Remarkably, the force in the low Mach number limit does not depend on the velocity. The equilibrium speed, when it exists, is set by the cancellation of the standard dynamical friction and heating force. In the low Mach number limit, it scales with the luminosity-to-mass ratio of the perturber. Using the above results suggests that Mars- to Earth-sized planetary embryos heated by accretion in a gaseous protoplanetary disc should have eccentricities and inclinations that amount to a sizeable fraction of the disc's aspect ratio, for conditions thought to prevail at a few astronomical units.

Burden and Risk Factors for Cold-Related Illness and Death in New York City

PubMed Central

Lane, Kathryn; Ito, Kazuhiko; Johnson, Sarah; Gibson, Elizabeth A.; Matte, Thomas

2018-01-01

Exposure to cold weather can cause cold-related illness and death, which are preventable. To understand the current burden, risk factors, and circumstances of exposure for illness and death directly attributed to cold, we examined hospital discharge, death certificate, and medical examiner data during the cold season from 2005 to 2014 in New York City (NYC), the largest city in the United States. On average each year, there were 180 treat-and-release emergency department visits (average annual rate of 21.6 per million) and 240 hospital admissions (29.6 per million) for cold-related illness, and 15 cold-related deaths (1.8 per million). Seventy-five percent of decedents were exposed outdoors. About half of those exposed outdoors were homeless or suspected to be homeless. Of the 25% of decedents exposed indoors, none had home heat and nearly all were living in single-family or row homes. The majority of deaths and illnesses occurred outside of periods of extreme cold. Unsheltered homeless individuals, people who use substances and become incapacitated outdoors, and older adults with medical and psychiatric conditions without home heat are most at risk. This information can inform public health prevention strategies and interventions. PMID:29601479

A Virtual Rat for Simulating Environmental and Exertional Heat Stress

DTIC Science & Technology

2014-10-02

unsuitable for accurately determin- ing the spatiotemporal temperature distribution in the animal due to heat stress and for performing mechanistic analysis ...possible in the original experiments. Finally, we performed additional simu- lations using the virtual rat to facilitate comparative analysis of the...capability of the virtual rat to account for the circadian rhythmicity in core temperatures during an in- crease in the external temperature from 22

The Army Ambulatory Care Data Base (ACDB) Study: Implementation and Preliminary Data

DTIC Science & Technology

1988-09-01

NUMBNESS/T1’NGLING 009919 COLD INJURY - 55891 DIARRHEA (’(73449 PARALYSIS 00929 HEAT INJURY - 55890 GASTITOENTERITiS C) C)7803 SEIZURE DISORDER...illnesses or injuries which had resolved themselves or to indicate that there was no discernible illness/ injury present. Unfortunately, this problem was not...34normal state" or "feared condition was not demonstrated." It was believed that certain occurrences of injury or illness would not be supportable and

Climate and heat-related emergencies in Chicago, Illinois (2003-2006).

PubMed

Hartz, Donna A; Golden, Jay S; Sister, Chona; Chuang, Wen-Ching; Brazel, Anthony J

2012-01-01

Extreme heat events are responsible for more deaths in the United States than floods, hurricanes and tornados combined. Yet, highly publicized events, such as the 2003 heat wave in Europe which caused in excess of 35,000 deaths, and the Chicago heat wave of 1995 that produced over 500 deaths, draw attention away from the countless thousands who, each year, fall victim to nonfatal health emergencies and illnesses directly attributed to heat. The health impact of heat waves and excessive heat are well known. Cities worldwide are seeking to better understand heat-related illnesses with respect to the specifics of climate, social demographics and spatial distributions. This information can support better preparation for heat-related emergency situations with regards to planning for response capacity and placement of emergency resources and personnel. This study deals specifically with the relationship between climate and heat-related dispatches (HRD, emergency 911 calls) in Chicago, Illinois, between 2003 and 2006. It is part of a larger, more in-depth, study that includes urban morphology and social factors that impact heat-related emergency dispatch calls in Chicago. The highest occurrences of HRD are located in the central business district, but are generally scattered across the city. Though temperature can be a very good predictor of high HRD, heat index is a better indicator. We determined temperature and heat index thresholds for high HRD. We were also able to identify a lag in HRD as well as other situations that triggered higher (or lower) HRD than would typically be generated for the temperature and humidity levels, such as early afternoon rainfall and special events.

Climate and heat-related emergencies in Chicago, Illinois (2003-2006)

NASA Astrophysics Data System (ADS)

Hartz, Donna A.; Golden, Jay S.; Sister, Chona; Chuang, Wen-Ching; Brazel, Anthony J.

2012-01-01

Extreme heat events are responsible for more deaths in the United States than floods, hurricanes and tornados combined. Yet, highly publicized events, such as the 2003 heat wave in Europe which caused in excess of 35,000 deaths, and the Chicago heat wave of 1995 that produced over 500 deaths, draw attention away from the countless thousands who, each year, fall victim to nonfatal health emergencies and illnesses directly attributed to heat. The health impact of heat waves and excessive heat are well known. Cities worldwide are seeking to better understand heat-related illnesses with respect to the specifics of climate, social demographics and spatial distributions. This information can support better preparation for heat-related emergency situations with regards to planning for response capacity and placement of emergency resources and personnel. This study deals specifically with the relationship between climate and heat-related dispatches (HRD, emergency 911 calls) in Chicago, Illinois, between 2003 and 2006. It is part of a larger, more in-depth, study that includes urban morphology and social factors that impact heat-related emergency dispatch calls in Chicago. The highest occurrences of HRD are located in the central business district, but are generally scattered across the city. Though temperature can be a very good predictor of high HRD, heat index is a better indicator. We determined temperature and heat index thresholds for high HRD. We were also able to identify a lag in HRD as well as other situations that triggered higher (or lower) HRD than would typically be generated for the temperature and humidity levels, such as early afternoon rainfall and special events.

Estimating the Prevalence of Heat-Related Symptoms and Sun Safety-Related Behavior among Latino Farmworkers in Eastern North Carolina.

PubMed

Kearney, Gregory D; Hu, Hui; Xu, Xiaohui; Hall, Marla B; Balanay, Jo Anne G

2016-01-01

In hot weather, thermal heat generated by the body, combined with environmental heat from the sun, can lead outdoor workers to experience heat-related stress, severe illness, or even death. The aims of this study were to estimate the prevalence of heat-related symptoms and potential risk factors associated with sun safety-related behavior among Latino farmworkers. Data from interviewer-administered questionnaires were collected from a cross-sectional survey among farmworkers (N = 158) from August to September 2013. Data analysis assessed associations between work activities, sun safety behavior, and the prevalence of heat-related illness (HRI) symptoms among workers. Nearly two thirds (72%) of farmworkers experienced at least one HRI symptom and lacked proper cooling methods when working outdoors. Most workers reported wearing long-sleeved shirts (85%), long pants (98%), and baseball caps (93%). The prevalence of having one HRI symptom was 72% and 27% among workers having three or more HRI symptoms. The majority of farmworkers experience symptoms of HRI and are not provided with proper shade protection when working outdoors. Increased emphasis on administrative controls, particularly educating field supervisors and workers on how to avoid and recognize HRI, should be a priority.

Medical students' attitudes to mental illnesses and to psychiatry before and after the psychiatric clerkship: Training in a specialty and a general hospital.

PubMed

Economou, Marina; Kontoangelos, Kontantinos; Peppou, Lily Evangelia; Arvaniti, Aikaterini; Samakouri, Maria; Douzenis, Athanasios; Papadimitriou, George N

2017-12-01

Medical students' attitudes to mental illnesses and psychiatry may be reshaped during the psychiatric training, with important implications in their future practice of the profession. Therefore, the present study set out to explore the impact of the psychiatric clerkship in students' attitudes, while taking into consideration the site of their practical training. To this end, a total of 678 final-year medical students were recruited. Students completed a self-reported questionnaire entailing the Attitudes to Psychiatry scale, the Attitudes to Mental Illness scale and the Greek Social Distance scale before and after their placement. Findings indicate that the psychiatric clerkship had a positive effect in reducing stigma towards both psychiatry and mental illnesses, with the effect being more pronounced in the general hospital with respect to the former, while in the specialty hospital was more marked regarding the latter. A further exploration of the determinants of change revealed that the improvement discerned in the general hospital was only among those without professional experience of mental illnesses. Therefore, the psychiatric clerkship may exert a substantial influence on shaping favourable attitudes towards mental illnesses and psychiatry; however, other elements should also be taken into consideration, if the clerkship is to tackle stigma in healthcare. Copyright © 2017 Elsevier B.V. All rights reserved.

National Athletic Trainers' Association Position Statement: Preventing Sudden Death in Sports

PubMed Central

Casa, Douglas J.; Guskiewicz, Kevin M.; Anderson, Scott A.; Courson, Ronald W.; Heck, Jonathan F.; Jimenez, Carolyn C.; McDermott, Brendon P.; Miller, Michael G.; Stearns, Rebecca L.; Swartz, Erik E.; Walsh, Katie M.

2012-01-01

Objective: To present recommendations for the prevention and screening, recognition, and treatment of the most common conditions resulting in sudden death in organized sports. Background: Cardiac conditions, head injuries, neck injuries, exertional heat stroke, exertional sickling, asthma, and other factors (eg, lightning, diabetes) are the most common causes of death in athletes. Recommendations: These guidelines are intended to provide relevant information on preventing sudden death in sports and to give specific recommendations for certified athletic trainers and others participating in athletic health care. PMID:22488236

Goddard Cumulus Ensemble (GCE) Model: Application for Understanding Preciptation Processes

NASA Technical Reports Server (NTRS)

Tao, Wei-Kuo; Einaudi, Franco (Technical Monitor)

2000-01-01

The global hydrological cycle is central to climate system interactions and the key to understanding their behavior. Rainfall and its associated precipitation processes are a key link in the hydrologic cycle. Fresh water provided by tropical rainfall and its variability can exert a large impact upon the structure of the upper ocean layer. In addition, approximately two-thirds of the global rain falls in the Tropics, while the associated latent heat release accounts for about three-fourths of the total heat energy for the Earth's atmosphere. Precipitation from convective cloud systems comprises a large portion of tropical heating and rainfall. Furthermore, the vertical distribution of convective latent-heat releases modulates large-scale tropical circulations (e.g., the 30-60-day intraseasonal oscillation), which, in turn, impacts midlatitude weather through teleconnection patterns such as those associated with El Nino. Shifts in these global circulations can result in prolonged periods of droughts and floods, thereby exerting a tremendous impact upon the biosphere and human habitation. And yet, monthly rainfall over the tropical oceans is still not known within a factor of two over large (5 degrees latitude by 5 degrees longitude) areas. Hence, the Tropical Rainfall Measuring Mission (TRMM), a joint U.S./Japan space project, can provide a more accurate measurement of rainfall as well as estimate the four-dimensional structure of diabatic heating over the global tropics. The distributions of rainfall and inferred heating can be used to advance our understanding of the global energy and water cycle. In addition, this information can be used for global circulation and climate models for testing and improving their parameterizations.

Comparison of different cooling regimes within a shortened liquid cooling/warming garment on physiological and psychological comfort during exercise

NASA Technical Reports Server (NTRS)

Leon, Gloria R.; Koscheyev, Victor S.; Coca, Aitor; List, Nathan

2004-01-01

The aim of this study was to compare the effectiveness of different cooling regime intensities to maintain physiological and subjective comfort during physical exertion levels comparable to that engaged in during extravehicular activities (EVA) in space. We studied eight subjects (six males, two females) donned in our newly developed physiologically based shortened liquid cooling/warming garment (SLCWG). Rigorous (condition 1) and mild (condition 2) water temperature cooling regimes were compared at physical exertion levels comparable to that performed during EVA to ascertain the effectiveness of a lesser intensity of cooling in maintaining thermal comfort, thus reducing energy consumption in the portable life support system. Exercise intensity was varied across stages of the session. Finger temperature, rectal temperature, and subjective perception of overall body and hand comfort were assessed. Finger temperature was significantly higher in the rigorous cooling condition and showed a consistent increase across exercise stages, likely due to the restriction of heat extraction because of the intensive cold. In the mild cooling condition, finger temperature exhibited an overall decline with cooling, indicating greater heat extraction from the body. Rectal temperature was not significantly different between conditions, and showed a steady increase over exercise stages in both rigorous and mild cooling conditions. Ratings of overall comfort were 30% higher (more positive) and more stable in mild cooling (p<0.001). The mild cooling regime was more effective than rigorous cooling in allowing the process of heat exchange to occur, thus maintaining thermal homeostasis and subjective comfort during physical exertion.

Perceived heat stress and health effects on construction workers.

PubMed

Dutta, Priya; Rajiva, Ajit; Andhare, Dileep; Azhar, Gulrez Shah; Tiwari, Abhiyant; Sheffield, Perry

2015-01-01

Increasing heat waves-particularly in urban areas where construction is most prevalent, highlight a need for heat exposure assessment of construction workers. This study aims to characterize the effects of heat on construction workers from a site in Gandhinagar. This study involved a mixed methods approach consisting of a cross sectional survey with anthropometric measurements (n = 219) and four focus groups with construction workers, as well as environmental measurements of heat stress exposure at a construction site. Survey data was collected in two seasons i.e., summer and winter months, and heat illness and symptoms were compared between the two time periods. Thematic coding of focus group data was used to identify vulnerability factors and coping mechanisms of the workers. Heat stress, recorded using a wet bulb globe temperature monitor, was compared to international safety standards. The survey findings suggest that heat-related symptoms increased in summer; 59% of all reports in summer were positive for symptoms (from Mild to Severe) as compared to 41% in winter. Focus groups revealed four dominant themes: (1) Non-occupational stressors compound work stressors; (2) workers were particularly attuned to the impact of heat on their health; (3) workers were aware of heat-related preventive measures; and (4) few resources were currently available to protect workers from heat stress. Working conditions often exceed international heat stress safety thresholds. Female workers and new employees might be at increased risk of illness or injury. This study suggests significant health impacts on construction workers from heat stress exposure in the workplace, showed that heat stress levels were higher than those prescribed by international standards and highlights the need for revision of work practices, increased protective measures, and possible development of indigenous work safety standards for heat exposure.

Perceived heat stress and health effects on construction workers

PubMed Central

Dutta, Priya; Rajiva, Ajit; Andhare, Dileep; Azhar, Gulrez Shah; Tiwari, Abhiyant; Sheffield, Perry

2015-01-01

Introduction: Increasing heat waves-particularly in urban areas where construction is most prevalent, highlight a need for heat exposure assessment of construction workers. This study aims to characterize the effects of heat on construction workers from a site in Gandhinagar. Materials and Methods: This study involved a mixed methods approach consisting of a cross sectional survey with anthropometric measurements (n = 219) and four focus groups with construction workers, as well as environmental measurements of heat stress exposure at a construction site. Survey data was collected in two seasons i.e., summer and winter months, and heat illness and symptoms were compared between the two time periods. Thematic coding of focus group data was used to identify vulnerability factors and coping mechanisms of the workers. Heat stress, recorded using a wet bulb globe temperature monitor, was compared to international safety standards. Results: The survey findings suggest that heat-related symptoms increased in summer; 59% of all reports in summer were positive for symptoms (from Mild to Severe) as compared to 41% in winter. Focus groups revealed four dominant themes: (1) Non-occupational stressors compound work stressors; (2) workers were particularly attuned to the impact of heat on their health; (3) workers were aware of heat-related preventive measures; and (4) few resources were currently available to protect workers from heat stress. Working conditions often exceed international heat stress safety thresholds. Female workers and new employees might be at increased risk of illness or injury. Conclusion: This study suggests significant health impacts on construction workers from heat stress exposure in the workplace, showed that heat stress levels were higher than those prescribed by international standards and highlights the need for revision of work practices, increased protective measures, and possible development of indigenous work safety standards for heat exposure. PMID:26957814

Thermoregulatory and Perceptual Effects of a Percooling Garment Worn Underneath an American Football Uniform.

PubMed

Keen, Megan L; Miller, Kevin C; Zuhl, Micah N

2017-11-01

Keen, ML, Miller, KC, and Zuhl, MN. Thermoregulatory and perceptual effects of a percooling garment worn underneath an American football uniform. J Strength Cond Res 31(11): 2983-2991, 2017-American football athletes are at the highest risk of developing exertional heat illness (EHI). We investigated whether percooling (i.e., cooling during exercise) garments affected perceptual or physiological variables in individuals exercising in the heat while wearing football uniforms. Twelve male participants (age = 24 ± 4 year, mass = 80.1 ± 8.5 kg, height = 182.5 ± 10.4 cm) completed this cross-over, counterbalanced study. On day 1, we measured peak oxygen consumption (V[Combining Dot Above]O2). On days 2 and 3, participants wore percooling garments with (ICE) or without (CON) ice packs over the femoral and brachial arteries. They donned a football uniform and completed 3, 20-minute bouts of treadmill exercise at ∼50% of peak V[Combining Dot Above]O2 (∼33° C, ∼42% relative humidity) followed by a 10-minute rest period. Ice packs were replaced every 20 minutes. Rating of perceived exertion (RPE), thermal sensation, and thirst sensation were measured before and after each exercise bout. Environmental symptoms questionnaire (ESQ) responses and urine specific gravity (Usg) were measured pretesting and after the last exercise bout. V[Combining Dot Above]O2, change in heart rate (ΔHR), and change in rectal temperature (ΔTrec) were measured every 5 minutes. Sweat rate, sweat volume, and percent hypohydration were calculated. No interactions (F17,187 ≤ 1.6, p ≥ 0.1) or main effect of cooling condition (F1,11 ≤ 1.4, p ≥ 0.26) occurred for ΔTrec, ΔHR, thermal sensation, thirst, RPE, ESQ, or Usg. No differences between conditions occurred for sweat volume, sweat rate, or percent hypohydration (t11 ≤ 0.7, p ≥ 0.25). V[Combining Dot Above]O2 differed between conditions over time (F15,165 = 3.3, p < 0.001); ICE was lower than CON at 30, 55, and 70 minutes (p ≤ 0.05). It is unlikely that these garments would prevent EHI or minimize dehydration in football athletes.

American College of Sports Medicine Roundtable on Exertional Heat Stroke - Return to Duty/Return to Play: Conference Proceedings

DTIC Science & Technology

2010-01-01

individuals with EHS experience long-term complica- tions that may include multisystem organ (liver, kidney, muscle ) and neurologic damage, as well as... reduced exercise capacity and heat intolerance (12,52,57,69). Animal and human research suggest late or untreated EHS may result in organ damage that...collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and

Interleukin-6 responses to water immersion therapy after acute exercise heat stress: a pilot investigation.

PubMed

Lee, Elaine C; Watson, Greig; Casa, Douglas; Armstrong, Lawrence E; Kraemer, William; Vingren, Jakob L; Spiering, Barry A; Maresh, Carl M

2012-01-01

Cold-water immersion is the criterion standard for treatment of exertional heat illness. Cryotherapy and water immersion also have been explored as ergogenic or recovery aids. The kinetics of inflammatory markers, such as interleukin-6 (IL-6), during cold-water immersion have not been characterized. To characterize serum IL-6 responses to water immersion at 2 temperatures and, therefore, to initiate further research into the multidimensional benefits of immersion and the evidence-based selection of specific, optimal immersion conditions by athletic trainers. Controlled laboratory study. Human performance laboratory Patients or Other Participants: Eight college-aged men (age = 22 ± 3 years, height = 1.76 ± 0.08 m, mass = 77.14 ± 9.77 kg, body fat = 10% ± 3%, and maximal oxygen consumption = 50.48 ± 4.75 mL·kg(-1) min(-1)). Participants were assigned randomly to receive either cold (11.70°C ± 2.02°C, n = 4) or warm (23.50°C ± 1.00°C, n = 4) water-bath conditions after exercise in the heat (temperature = 37°C, relative humidity = 52%) for 90 minutes or until volitional cessation. Whole-body cooling rates were greater in the cold water-bath condition for the first 6 minutes of water immersion, but during the 90-minute, postexercise recovery, participants in the warm and cold water-bath conditions experienced similar overall whole-body cooling. Heart rate responses were similar for both groups. Participants in the cold water-bath condition experienced an overall slight increase (30.54% ± 77.37%) in IL-6 concentration, and participants in the warm water-bath condition experienced an overall decrease (-69.76% ± 15.23%). We have provided seed evidence that cold-water immersion is related to subtle IL-6 increases from postexercise values and that warmer water-bath temperatures might dampen this increase. Further research will elucidate any anti-inflammatory benefit associated with water-immersion treatment and possible multidimensional uses of cooling therapies.

Symptoms of respiratory illness in young children and the use of wood-burning stoves for indoor heating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Honicky, R.E.; Osborne, J.S.; Akpom, C.A.

1985-03-01

The occurrence of symptoms of respiratory illness among preschool children living in homes heated by wood-burning stoves was examined by conducting an historical prospective study (n . 62) with an internal control group (matched for age, sex, and town of residence). Exposures of subjects were not significantly different (P greater than .05) with respect to parental smoking, urea-formaldehyde foam insulation, and use of humidifiers. The control group made significantly greater use of gas stoves for cooking whereas the study group made greater use of electric stoves for cooking and of air filters (P less than .05). Only one home usedmore » a kerosene space heater. During the winter of 1982, moderate and severe symptoms in all categories were significantly greater for the study group compared with the control group (P less than .001). These differences could not be accounted for by medical histories (eg, allergies, asthma), demographic or socioeconomic characteristics, or by exposure to sources of indoor air pollution other than wood-burning stoves. Present findings suggest that indoor heating with wood-burning stoves may be a significant etiologic factor in the occurrence of symptoms of respiratory illness in young children.« less

Neural basis of exertional fatigue in the heat: A review of magnetic resonance imaging methods.

PubMed

Tan, X R; Low, I C C; Stephenson, M C; Soong, T W; Lee, J K W

2018-03-01

The central nervous system, specifically the brain, is implicated in the development of exertional fatigue under a hot environment. Diverse neuroimaging techniques have been used to visualize the brain activity during or after exercise. Notably, the use of magnetic resonance imaging (MRI) has become prevalent due to its excellent spatial resolution and versatility. This review evaluates the significance and limitations of various brain MRI techniques in exercise studies-brain volumetric analysis, functional MRI, functional connectivity MRI, and arterial spin labeling. The review aims to provide a summary on the neural basis of exertional fatigue and proposes future directions for brain MRI studies. A systematic literature search was performed where a total of thirty-seven brain MRI studies associated with exercise, fatigue, or related physiological factors were reviewed. The findings suggest that with moderate dehydration, there is a decrease in total brain volume accompanied with expansion of ventricular volume. With exercise fatigue, there is increased activation of sensorimotor and cognitive brain areas, increased thalamo-insular activation and decreased interhemispheric connectivity in motor cortex. Under passive hyperthermia, there are regional changes in cerebral perfusion, a reduction in local connectivity in functional brain networks and an impairment to executive function. Current literature suggests that the brain structure and function are influenced by exercise, fatigue, and related physiological perturbations. However, there is still a dearth of knowledge and it is hoped that through understanding of MRI advantages and limitations, future studies will shed light on the central origin of exertional fatigue in the heat. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Fever

MedlinePlus

... causes of fevers include Medicines, including some antibiotics, blood pressure medicines, and anti-seizure medicines Heat illness Cancers Autoimmune diseases Some childhood immunizations Treatment ...

Heart rate variability during exertional heat stress: effects of heat production and treatment.

PubMed

Flouris, Andreas D; Bravi, Andrea; Wright-Beatty, Heather E; Green, Geoffrey; Seely, Andrew J; Kenny, Glen P

2014-04-01

We assessed the efficacy of different treatments (i.e., treatment with ice water immersion vs. natural recovery) and the effect of exercise intensities (i.e., low vs. high) for restoring heart rate variability (HRV) indices during recovery from exertional heat stress (EHS). Nine healthy adults (26 ± 3 years, 174.2 ± 3.8 cm, 74.6 ± 4.3 kg, 17.9 ± 2.8 % body fat, 57 ± 2 mL·kg·(-1) min(-1) peak oxygen uptake) completed four EHS sessions incorporating either walking (4.0-4.5 km·h(-1), 2 % incline) or jogging (~7.0 km·h(-1), 2 % incline) on a treadmill in a hot-dry environment (40 °C, 20-30 % relative humidity) while wearing a non-permeable rain poncho for a slow or fast rate of rectal temperature (T re) increase, respectively. Upon reaching a T re of 39.5 °C, participants recovered until T re returned to 38 °C either passively or with whole-body immersion in 2 °C water. A comprehensive panel of 93 HRV measures were computed from the time, frequency, time-frequency, scale-invariant, entropy and non-linear domains. Exertional heat stress significantly affected 60/93 HRV measures analysed. Analyses during recovery demonstrated that there were no significant differences between HRV measures that had been influenced by EHS at the end of passive recovery vs. whole-body cooling treatment (p > 0.05). Nevertheless, the cooling treatment required statistically significantly less time to reduce T re (p < 0.001). While EHS has a marked effect on autonomic nervous system modulation and whole-body immersion in 2 °C water results in faster cooling, there were no observed differences in restoration of autonomic heart rate modulation as measured by HRV indices with whole-body cold-water immersion compared to passive recovery in thermoneutral conditions.

Heat Exhaustion in a Rat Model: Lithium as a Biochemical Probe

DTIC Science & Technology

1989-09-30

depletion, potassium wasting, polyuria , and abnormal thermoregulation (2,3,8-17). Each of these effects may predispose to developing heat-induced illness...control and lithium groups. Lithium treatment in humans has often been associated with polyuria (10,16) thought to be secondary to renal toxicity of

Spouses' involvement in their partners' diabetes management: associations with spouse stress and perceived marital quality.

PubMed

August, Kristin J; Rook, Karen S; Franks, Melissa M; Parris Stephens, Mary Ann

2013-10-01

Spouses frequently attempt to influence (control) or support their chronically ill partners' adherence behaviors. Studies have documented effects of spousal control and support on chronically ill individuals, but little is known about how these two forms of involvement in a partner's disease management may be associated with spouses' stress or the quality of their interactions with their ill partners. The current study sought to address this gap by examining spouses' day-to-day involvement in their marital partner's management of type 2 diabetes (n = 129). Multilevel analyses of daily diary data revealed that on days when spouses exerted control, they reported more stress and more tense marital interactions, although these associations were more pronounced when patients exhibited poor adherence, had been ill for a longer period of time, and had more comorbid health conditions. On days when spouses provided support, in contrast, they reported less stress and more enjoyable marital interactions. The findings from the current study suggest that spouses' day-to-day stress and quality of interactions with their partners are associated with spouses' involvement in their partners' disease management, with health-related social control and support exhibiting distinctive associations.

A prospective randomised trial of probiotics in critically ill patients.

PubMed

McNaught, Clare E; Woodcock, Nicholas P; Anderson, Alexander D G; MacFie, John

2005-04-01

Probiotics exert a beneficial effect on the host through modulation of gastrointestinal microflora. The aim of this study was to investigate the effect of the probiotic Lactobacillus plantarum 299v on gut barrier function and the systemic inflammatory response in critically ill patients. One hundred and three critically ill patients were randomised to receive an oral preparation containing L. plantarum 299v (ProViva) in addition to conventional therapy (treatment group, n = 52) or conventional therapy alone (control group, n = 51). Serial outcome measures included gastric colonisation, intestinal permeability (lactulose/rhamnose dual-sugar probe technique), endotoxin exposure (IgM EndoCAb), C-reactive protein and Interleukin 6 levels. L. plantarum had no identifiable effect on gastric colonisation, intestinal permeability, endotoxin exposure or serum CRP levels. There were no differences between the groups in terms of septic morbidity or mortality. On day 15 serum IL-6 levels were significantly lower in the treatment group compared to controls. The enteral administration of L. plantarum 299v to critically ill patients was associated with a late attenuation of the systemic inflammatory response. This was not accompanied by any significant changes in the intestinal microflora, intestinal permeability, endotoxin exposure, septic morbidity or mortality.

Exogenous Salicylic Acid Enhances the Resistance of Wheat Seedlings to Hessian Fly (Diptera: Cecidomyiidae) Infestation Under Heat Stress.

PubMed

Underwood, Joshua; Moch, John; Chen, Ming-Shun; Zhu, Lieceng

2014-10-01

Heat stress exerts significant impact on plant-parasite interactions. Phytohormones, such as salicylic acid (SA), play important roles in plant defense against parasite attacks. Here, we studied the impact of a combination of heat stress and exogenous SA on the resistance of wheat (Triticum aestivum L.) plants to the Hessian fly [Mayetiola destructor (Say)]. We found that the wheat cultivar 'Molly', which contains the resistance gene H13, lost resistance to Hessian fly under heat stress (40°C for 3 and 6 h), and that exogenous application of SA on Molly seedlings right before heat stress can partially prevent the loss of resistance of Molly plants under heat conditions. Our findings have significant implications for understanding the dynamics of plant-insect interactions in the context of heat stress. © 2014 Entomological Society of America.

Thermoregulation, Fluid Balance, and Sweat Losses in American Football Players.

PubMed

Davis, Jon K; Baker, Lindsay B; Barnes, Kelly; Ungaro, Corey; Stofan, John

2016-10-01

Numerous studies have reported on the thermoregulation and hydration challenges athletes face in team and individual sports during exercise in the heat. Comparatively less research, however, has been conducted on the American Football player. Therefore, the purpose of this article is to review data collected in laboratory and field studies and discuss the thermoregulation, fluid balance, and sweat losses of American Football players. American Football presents a unique challenge to thermoregulation compared with other sports because of the encapsulating nature of the required protective equipment, large body size of players, and preseason practice occurring during the hottest time of year. Epidemiological studies report disproportionately higher rates of exertional heat illness and heat stroke in American Football compared with other sports. Specifically, larger players (e.g., linemen) are at increased risk for heat ailments compared with smaller players (e.g., backs) because of greater body mass index, increased body fat, lower surface area to body mass ratio, lower aerobic capacity, and the stationary nature of the position, which can reduce heat dissipation. A consistent finding across studies is that larger players exhibit higher sweating rates than smaller players. Mean sweating rates from 1.0 to 2.9 L/h have been reported for college and professional American Football players, with several studies reporting 3.0 L/h or more in some larger players. Sweat sodium concentration of American Football players does not seem to differ from that of athletes in other sports; however, given the high volume of sweat loss, the potential for sodium loss is higher in American Football than in other sports. Despite high sweating rates with American Football players, the observed disturbances in fluid balance have generally been mild (mean body mass loss ≤2 %). The majority of field-based studies have been conducted in the northeastern part of the United States, with limited studies in different geographical regions (i.e., southeast) of the United States. Further, there have been a limited number of studies examining body core temperature of American Football players during preseason practice, especially at the high school level. Future field-based research in American Football with various levels of competition in hotter geographical regions of the United States is warranted.

Risk Factors for Heat-related Illness in U.S. Workers: An OSHA Case Series.

PubMed

Tustin, Aaron W; Cannon, Dawn L; Arbury, Sheila B; Thomas, Richard J; Hodgson, Michael J

2018-05-30

The aim of this study was to describe risk factors for heat-related illness (HRI) in U.S. workers. We reviewed a subset of HRI enforcement investigations conducted by the Occupational Safety and Health Administration (OSHA) from 2011 through 2016. We assessed characteristics of the workers, employers, and events. We stratified cases by severity to assess whether risk factors were more prevalent in fatal HRIs. We analyzed 38 investigations involving 66 HRIs. Many workers had predisposing medical conditions or used predisposing medications. Comorbidities were more prevalent in workers who died. Most (73%) fatal HRIs occurred during the first week on the job. Common clinical findings in heat stroke cases included multiorgan failure, muscle breakdown, and systemic inflammation. Severe HRI is more likely when personal susceptibilities coexist with work-related and environmental risk factors. Almost all HRIs occur when employers do not adhere to preventive guidelines.

Integration of Decentralized Thermal Storages Within District Heating (DH) Networks

NASA Astrophysics Data System (ADS)

Schuchardt, Georg K.

2016-12-01

Thermal Storages and Thermal Accumulators are an important component within District Heating (DH) systems, adding flexibility and offering additional business opportunities for these systems. Furthermore, these components have a major impact on the energy and exergy efficiency as well as the heat losses of the heat distribution system. Especially the integration of Thermal Storages within ill-conditioned parts of the overall DH system enhances the efficiency of the heat distribution. Regarding an illustrative and simplified example for a DH system, the interactions of different heat storage concepts (centralized and decentralized) and the heat losses, energy and exergy efficiencies will be examined by considering the thermal state of the heat distribution network.

Coal home heating and environmental tobacco smoke in relation to lower respiratory illness in Czech children, from birth to 3 years of age

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, R.J.; Hert-Picciotto, I.; Dostal, M.

2006-07-15

The objective of this study was to evaluate how indoor pollution from tobacco and home heating may adversely affect respiratory health in young children. A total of 452 children born 1994-1996 in two districts in the Czech Republic participated. Lower respiratory illness (LRI) diagnoses occurred more frequently in children from homes heated by coal (vs. other energy sources or distant furnaces; rate ratio (RR) = 1.45; 95% confidence interval (CI), 1.07-1.97). Maternal prenatal smoking and other adult smokers also increased LRI rates (respectively: RR = 1.48; 95% CI, 1.10-2.01; and RR = 1.29; 95% CI, 1.01-1.65). Cooking fuels (primarily electricity,more » natural gas, or propane) were not associated with LRI incidence. For children never breast-fed, coal home heating and mother's smoking conferred substantially greater risks: RR = 2.77 (95% CI, 1.45-5.27) and RR = 2.52 (95% CI, 1.31-4.85), respectively. This maternal smoking and coal home heating increased risk for LRI in the first 3 years of life, particularly in children not breast-fed.« less

Heat Control via Torque Control in Friction Stir Welding

NASA Technical Reports Server (NTRS)

Venable, Richard; Colligan, Kevin; Knapp, Alan

2004-01-01

In a proposed advance in friction stir welding, the torque exerted on the workpiece by the friction stir pin would be measured and controlled in an effort to measure and control the total heat input to the workpiece. The total heat input to the workpiece is an important parameter of any welding process (fusion or friction stir welding). In fusion welding, measurement and control of heat input is a difficult problem. However, in friction stir welding, the basic principle of operation affords the potential of a straightforward solution: Neglecting thermal losses through the pin and the spindle that supports it, the rate of heat input to the workpiece is the product of the torque and the speed of rotation of the friction stir weld pin and, hence, of the spindle. Therefore, if one acquires and suitably processes data on torque and rotation and controls the torque, the rotation, or both, one should be able to control the heat input into the workpiece. In conventional practice in friction stir welding, one uses feedback control of the spindle motor to maintain a constant speed of rotation. According to the proposal, one would not maintain a constant speed of rotation: Instead, one would use feedback control to maintain a constant torque and would measure the speed of rotation while allowing it to vary. The torque exerted on the workpiece would be estimated as the product of (1) the torque-multiplication ratio of the spindle belt and/or gear drive, (2) the force measured by a load cell mechanically coupled to the spindle motor, and (3) the moment arm of the load cell. Hence, the output of the load cell would be used as a feedback signal for controlling the torque (see figure).

Evaluation of a Heat Vulnerability Index on Abnormally Hot Days: An Environmental Public Health Tracking Study

PubMed Central

Mann, Jennifer K.; Alfasso, Ruth; English, Paul B.; King, Galatea C.; Lincoln, Rebecca A.; Margolis, Helene G.; Rubado, Dan J.; Sabato, Joseph E.; West, Nancy L.; Woods, Brian; Navarro, Kathleen M.; Balmes, John R.

2012-01-01

Background: Extreme hot weather conditions have been associated with increased morbidity and mortality, but risks are not evenly distributed throughout the population. Previously, a heat vulnerability index (HVI) was created to geographically locate populations with increased vulnerability to heat in metropolitan areas throughout the United States. Objectives: We sought to determine whether areas with higher heat vulnerability, as characterized by the HVI, experienced higher rates of morbidity and mortality on abnormally hot days. Methods: We used Poisson regression to model the interaction of HVI and deviant days (days whose deviation of maximum temperature from the 30-year normal maximum temperature is at or above the 95th percentile) on hospitalization and mortality counts in five states participating in the Environmental Public Health Tracking Network for the years 2000 through 2007. Results: The HVI was associated with higher hospitalization and mortality rates in all states on both normal days and deviant days. However, associations were significantly stronger (interaction p-value < 0.05) on deviant days for heat-related illness, acute renal failure, electrolyte imbalance, and nephritis in California, heat-related illness in Washington, all-cause mortality in New Mexico, and respiratory hospitalizations in Massachusetts. Conclusion: Our results suggest that the HVI may be a marker of health vulnerability in general, although it may indicate greater vulnerability to heat in some cases. PMID:22538066

Identification of barriers to the prevention and treatment of heat-related illness in Latino farmworkers using activity-oriented, participatory rural appraisal focus group methods

PubMed Central

2013-01-01

Background Heat-related illness (HRI) is an important cause of non-fatal illness and death in farmworkers. We sought to identify potential barriers to HRI prevention and treatment in Latino farmworkers. Methods We conducted three semi-structured focus group discussions with 35 Latino farmworkers in the Central Washington, USA area using participatory rural appraisal techniques. Interviews were audio taped and transcribed in Spanish. Three researchers reviewed and coded transcripts and field notes, and investigator triangulation was used to identify relevant themes and quotes. Results Although the majority of participants in our study reported never receiving formal HRI training, most participants were aware that extreme heat can cause illness and were able to accurately describe HRI symptoms, risk factors, and certain prevention strategies. Four main observations regarding farmworkers’ HRI-relevant beliefs and attitudes were identified: 1) farmworkers subscribe to varying degrees to the belief that cooling treatments should be avoided after heat exposure, with some believing that such treatments should be avoided after heat exposure, and others encouraging the use of such treatments; 2) the desire to lose weight may be reflected in behaviors that promote increased sweating; 3) highly caffeinated energy drinks are preferred to increase work efficiency and maintain alertness; and 4) the location of drinking water at work (e.g. next to restrooms) and whether water is clean, but not necessarily chemically-treated, are important considerations in deciding whether to drink the water provided at worksites. Conclusions We identified potential barriers to HRI prevention and treatment related to hydration, certain HRI treatments, clothing use, and the desire to lose weight among Latino farmworkers. Strategies to address potential barriers to HRI prevention and treatment in this population may include engineering, administrative, and health education and health promotion strategies at individual, workplace, community, and societal levels. Although farmworkers in our study were able to describe HRI risk factors, reported practices were not necessarily consistent with reported knowledge. Further study of potential knowledge-behavior gaps may uncover opportunities for additional HRI prevention strategies. Farmworkers and employers should be included in the development and evaluation of interventions to prevent HRI. PMID:24156496

Identification of barriers to the prevention and treatment of heat-related illness in Latino farmworkers using activity-oriented, participatory rural appraisal focus group methods.

PubMed

Lam, Michelle; Krenz, Jennifer; Palmández, Pablo; Negrete, Maria; Perla, Martha; Murphy-Robinson, Helen; Spector, June T

2013-10-24

Heat-related illness (HRI) is an important cause of non-fatal illness and death in farmworkers. We sought to identify potential barriers to HRI prevention and treatment in Latino farmworkers. We conducted three semi-structured focus group discussions with 35 Latino farmworkers in the Central Washington, USA area using participatory rural appraisal techniques. Interviews were audio taped and transcribed in Spanish. Three researchers reviewed and coded transcripts and field notes, and investigator triangulation was used to identify relevant themes and quotes. Although the majority of participants in our study reported never receiving formal HRI training, most participants were aware that extreme heat can cause illness and were able to accurately describe HRI symptoms, risk factors, and certain prevention strategies. Four main observations regarding farmworkers' HRI-relevant beliefs and attitudes were identified: 1) farmworkers subscribe to varying degrees to the belief that cooling treatments should be avoided after heat exposure, with some believing that such treatments should be avoided after heat exposure, and others encouraging the use of such treatments; 2) the desire to lose weight may be reflected in behaviors that promote increased sweating; 3) highly caffeinated energy drinks are preferred to increase work efficiency and maintain alertness; and 4) the location of drinking water at work (e.g. next to restrooms) and whether water is clean, but not necessarily chemically-treated, are important considerations in deciding whether to drink the water provided at worksites. We identified potential barriers to HRI prevention and treatment related to hydration, certain HRI treatments, clothing use, and the desire to lose weight among Latino farmworkers. Strategies to address potential barriers to HRI prevention and treatment in this population may include engineering, administrative, and health education and health promotion strategies at individual, workplace, community, and societal levels. Although farmworkers in our study were able to describe HRI risk factors, reported practices were not necessarily consistent with reported knowledge. Further study of potential knowledge-behavior gaps may uncover opportunities for additional HRI prevention strategies. Farmworkers and employers should be included in the development and evaluation of interventions to prevent HRI.

Post-Exertional Malaise in Patients with ME and CFS with Comorbid Fibromyalgia.

PubMed

McManimen, Stephanie L; Jason, Leonard A

2017-01-01

Myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) share some similar symptoms with fibromyalgia (FM). Prior research has found increased illness severity when patients have FM that is comorbid with ME and CFS. For example, post-exertional malaise (PEM) has been shown to be more severe in those with comorbid FM. However, PEM can be separated into two factors, Muscle and General PEM. It is unknown if the more severe PEM findings in comorbid FM are due to the Muscle or General PEM factor. The purpose of this study was to determine if the PEM differences seen between patients with and without comorbid FM exist for the Muscle or General PEM factors. An international convenience sample was collected via an online questionnaire. The questionnaire assessed the frequency and severity of several PEM-related symptoms. Additionally, participants provided information regarding the course and characteristics of their illness. Participants that indicated a comorbid diagnosis of FM displayed significantly more frequent and severe PEM symptoms in the Muscle and General PEM factors. The FM group also indicated significantly worse physical functioning compared to the group without comorbid FM. The secondary diagnosis of FM in addition to ME and CFS appears to amplify the PEM symptomatology and worsen patients' physical functioning. The findings of this study have notable implications on the inclusion of patients with comorbid FM in ME and CFS research studies.

Development of Infrared Radiation Heating Method for Sustainable Tomato Peeling

USDA-ARS?s Scientific Manuscript database

Although lye peeling is the widely industrialized method for producing high quality peeled fruit and vegetable products, the peeling method has resulted in negative impacts by significantly exerting both environmental and economic pressure on the tomato processing industry due to its associated sali...

Weather, Climate, and You.

ERIC Educational Resources Information Center

Blai, Boris, Jr.

Information from the American Institute of Medical Climatologists on human responses to weather and climatic conditions, including clouds, winds, humidity, barometric pressure, heat, cold, and other variables that may exert a pervasive impact on health, behavior, disposition, and the level of efficiency with which individuals function is reviewed.…

Green infrastructure and urban sustainability

NASA Astrophysics Data System (ADS)

Hagishima, Aya

2018-02-01

Temperature increase in urban areas due to the urban heat island as well as the global climate change inevitably raises the peak load supply for space cooling as well as the risk of heat-related illness in hot climate. This paper provides the comprehensive review of the thermal mitigation effect of urban vegetation based on the field observations.

Rasburicase improves hyperuricemia in patients with acute kidney injury secondary to rhabdomyolysis caused by ecstasy intoxication and exertional heat stroke.

PubMed

Lin, Pei-Yi; Lin, Chun-Chen; Liu, Hsi-Che; Lee, Ming-Dar; Lee, Hung-Chang; Ho, Che-Sheng; Chiu, Nan-Chang; Peng, Chun-Chih; Huang, Fu-Yuan; Tsai, Jeng-Daw

2011-11-01

To report the successful use of rasburicase in two children with hyperuricemia secondary to severe rhabdomyolysis. : Case report. Pediatric intensive care unit in a freestanding quaternary hospital. Two pediatric patients with severe rhabdomyolysis and hyperuricemia caused by ecstasy intoxication and exertional heat stroke. Use of a single low dose (6 mg) of rasburicase, a urate oxidase enzyme. Rasburicase was administered on the first and second hospital days with a single low dose of 6 mg (0.086 mg/kg in patient A and 0.092 mg/kg in patient B). Within 24 hrs, the levels of serum uric acid in both patients decreased dramatically, and their creatinine levels decreased and urine output increased concurrently. Continuous improvements in the uric acid levels, creatinine levels, and urine output were noted during hospitalization. Rasburicase seems to be a safe and effective drug for improving hyperuricemia in patients with rhabdomyolysis and renal failure.

Unconventional Secretion of Heat Shock Proteins in Cancer

PubMed Central

Santos, Tiago Góss; Martins, Vilma Regina; Hajj, Glaucia Noeli Maroso

2017-01-01

Heat shock proteins (HSPs) are abundant cellular proteins involved with protein homeostasis. They have both constitutive and inducible isoforms, whose expression levels are further increased by stress conditions, such as temperature elevation, reduced oxygen levels, infection, inflammation and exposure to toxic substances. In these situations, HSPs exert a pivotal role in offering protection, preventing cell death and promoting cell recovery. Although the majority of HSPs functions are exerted in the cytoplasm and organelles, several lines of evidence reveal that HSPs are able to induce cell responses in the extracellular milieu. HSPs do not possess secretion signal peptides, and their secretion was subject to widespread skepticism until the demonstration of the role of unconventional secretion forms such as exosomes. Secretion of HSPs may confer immune system modulation and be a cell-to-cell mediated form of increasing stress resistance. Thus, there is a wide potential for secreted HSPs in resistance of cancer therapy and in the development new therapeutic strategies. PMID:28468249

New guidelines are needed to manage heat stress in elite sports--The Fédération Internationale de Volleyball (FIVB) Heat Stress Monitoring Programme.

PubMed

Bahr, Roald; Reeser, Jonathan C

2012-09-01

There seems to be a discrepancy between the available heat stress guidelines and the actual risk of heat-related illness among professional beach volleyball players competing under hot and humid conditions. To monitor heat stress and record cases of heat-related medical forfeits on the Swatch FIVB Beach Volleyball World Tour. The FIVB Heat Stress Monitoring Protocol covered events on the FIVB Beach Volleyball World Tour and FIVB Beach Volleyball World Championships during the 2009, 2010 and 2011 seasons (51 events, most of these double gender). The protocol consisted of (1) measuring the Wet Bulb Globe Temperature (WBGT) on centre court prior to the start of every match, and (2) recording any heat-related medical forfeits during the tournament. Data were collected during 48 of 51 events. There were nine events where the peak WBGT exceeded the US Navy Black flag conditions of >32.3°C and an additional two events where the peak WBGT exceeded 31°C, (meeting Red flag conditions.) In two events, the average WBGT equalled at least 31°C. One case of a medical forfeit related to heat stress was recorded over the 3-year surveillance period: an athlete whose fluid balance was compromised from a 3-day bout of acute gastroenteritis. The incidence of significant heat illness among athletes competing on the FIVB Beach Volleyball World Tour appears to be quite low, even though weather conditions frequently result in a WBGT index >32°C. Currently available guidelines appear to be inadequate to fully assess the risk of heat stress and too conservative to inform safety decisions in professional beach volleyball.

High-volume plasma exchange in a patient with acute liver failure due to non-exertional heat stroke in a sauna.

PubMed

Chen, Kuan-Jung; Chen, Tso-Hsiao; Sue, Yuh-Mou; Chen, Tzay-Jinn; Cheng, Chung-Yi

2014-10-01

Heat stroke is a life-threatening condition characterized by an increased core body temperature (over 40°C) and a systemic inflammatory response, which may lead to a syndrome of multiple organ dysfunction. Heat stroke may be due to either strenuous exercise or non-exercise-induced exposure to a high environmental temperature. Current management of heat stroke is mostly supportive, with an emphasis on cooling the core body temperature and preventing the development of multiple organ dysfunction. Prognosis of heat stroke depends on the severity of organ involvement. Here, we report a rare case of non-exercise-induced heat stroke in a 73-year-old male patient who was suffering from acute liver failure after prolonged exposure in a hot sauna room. We successfully managed this patient by administering high-volume plasma exchange, and the patient recovered completely after treatment. © 2014 Wiley Periodicals, Inc.

Radiant energy and insensible water loss in the premature newborn infant nursed under a radiant warmer.

PubMed

Baumgart, S

1982-10-01

Radiant warmers are a powerful and efficient source of heat serving to warm the cold-stressed infant acutely and to provide uninterrupted maintenance of body temperature despite a multiplicity of nursing, medical, and surgical procedures required to care for the critically ill premature newborn in today's intensive care nursery. A recognized side-effect of radiant warmer beds is the now well-documented increase in insensible water loss through evaporation from an infant's skin. Particularly the very-low-birth-weight, severely premature, and critically ill neonate is subject to this increase in evaporative water loss. The clinician caring for the infant is faced with the difficult problem of fluid and electrolyte balance, which requires vigilant monitoring of all parameters of fluid homeostasis. Compounding these difficulties, other portions of the electromagnetic spectrum (for example, phototherapy) may affect an infant's fluid metabolism by mechanisms that are not well understood. The role of plastic heat shielding in reducing large insensible losses in infants nursed on radiant warmer beds is currently under intense investigation. Apparently, convective air currents and not radiant heat energy may be the cause of the observed increase in insensible water loss in the intensive care nursery. A thin plastic blanket may be effective in reducing evaporative water loss by diminishing an infant's exposure to convective air currents while being nursed on an open radiant warmer bed. A rigid plastic body hood, although effective as a radiant heat shield, is not as effective in preventing exposure to convection in the intensive care nursery and, therefore, is not as effective as the thin plastic blanket in reducing insensible water loss. Care should be exercised in determining the effect of heat shielding on all parameters of heat exchange (convection, evaporation, and radiation) before application is made to the critically ill premature infant nursed on an open radiant warmer bed.

Spinning-induced Rhabdomyolysis: Eleven Case Reports and Review of the Literature

PubMed Central

Kim, Daejin; Ko, Eun-Jung; Cho, HyeJeong; Park, Su Hyung; Lee, Sang Hwan; Cho, Nam-gil; Lee, So-Young; Jeong, Hye Yun

2015-01-01

Non-traumatic exertional rhabdomyolysis (exRML) occurs in individuals with normal muscles when the energy supplied to the muscle is insufficient. Here, we report 11 cases of spinning-induced rhabdomyolysis and review related literature. Spinning is a kind of indoor bicycle sport. The 11 patients who were diagnosed with exRML and admitted to CHA Bundang Medical Center were female and their ages ranged from 15 to 46 years. Two to three days prior to the presentation, the patients had attended a spinning class for the first time. All the patients had been otherwise healthy without any known medical illnesses. They were successfully treated without any complications, except mild non-symptomatic hypocalcemia. However, in the literature, severe complications such as compartment syndrome or acute kidney injury had been reported in relation to exRML including spinning-induced rhabdomyolysis. This spinning exercise needs prior guidelines and specific warnings to prevent exertional rhabdomyolysis. PMID:26848305

The 2006 California Heat Wave: Impacts on Hospitalizations and Emergency Department Visits

PubMed Central

Knowlton, Kim; Rotkin-Ellman, Miriam; King, Galatea; Margolis, Helene G.; Smith, Daniel; Solomon, Gina; Trent, Roger; English, Paul

2009-01-01

Background Climate models project that heat waves will increase in frequency and severity. Despite many studies of mortality from heat waves, few studies have examined morbidity. Objectives In this study we investigated whether any age or race/ethnicity groups experienced increased hospitalizations and emergency department (ED) visits overall or for selected illnesses during the 2006 California heat wave. Methods We aggregated county-level hospitalizations and ED visits for all causes and for 10 cause groups into six geographic regions of California. We calculated excess morbidity and rate ratios (RRs) during the heat wave (15 July to 1 August 2006) and compared these data with those of a reference period (8–14 July and 12–22 August 2006). Results During the heat wave, 16,166 excess ED visits and 1,182 excess hospitalizations occurred statewide. ED visits for heat-related causes increased across the state [RR = 6.30; 95% confidence interval (CI), 5.67–7.01], especially in the Central Coast region, which includes San Francisco. Children (0–4 years of age) and the elderly (≥ 65 years of age) were at greatest risk. ED visits also showed significant increases for acute renal failure, cardiovascular diseases, diabetes, electrolyte imbalance, and nephritis. We observed significantly elevated RRs for hospitalizations for heat-related illnesses (RR = 10.15; 95% CI, 7.79–13.43), acute renal failure, electrolyte imbalance, and nephritis. Conclusions The 2006 California heat wave had a substantial effect on morbidity, including regions with relatively modest temperatures. This suggests that population acclimatization and adaptive capacity influenced risk. By better understanding these impacts and population vulnerabilities, local communities can improve heat wave preparedness to cope with a globally warming future. PMID:19165388

Tailor-made purified human platelet lysate concentrated in neurotrophins for treatment of Parkinson's disease.

PubMed

Chou, Ming-Li; Wu, Joe-Wei; Gouel, Flore; Jonneaux, Aurélie; Timmerman, Kelly; Renn, Ting-Yi; Laloux, Charlotte; Chang, Hung-Ming; Lin, Liang-Tzung; Devedjian, Jean-Christophe; Devos, David; Burnouf, Thierry

2017-10-01

Human platelet lysates (PLs), which contain multiple neurotrophins, have been proposed for treating neurodegenerative disorders, including Parkinson's disease (PD). However, current PLs suspended in plasma have high protein content and contain fibrinogen/fibrin and, following activation, also proteolytic and thrombogenic enzymes. Upon brain administration, such PLs may saturate the cerebrospinal fluid and exert neurotoxicity. We assessed whether purified PLs, concentrated in neurotrophins, protected dopaminergic neurons in PD models. Platelet concentrates were collected by apheresis and centrifuged to eliminate plasma and recover the platelets. Platelets were lysed by freeze-thaw cycles, and the 10-fold concentrated platelet pellet lysates (PPLs) were heat-treated (at 56 °C for 30 min). The heat-treated PPLs were low in total proteins, depleted in both plasma and platelet fibrinogen, and devoid of thrombogenic and proteolytic activities. They exerted very high neuroprotective activity when non-oncogenic, Lund human mesencephalic (LUHMES) cells that had differentiated into dopaminergic neurons were exposed to the MPP + neurotoxin. Heat treatment improved the neuroprotection and inactivated the neurotoxic blood-borne hepatitis C virus. PPL did not induce inflammation in BV2 microglial cells and inhibited COX-2 expression upon lipopolysaccharide exposure. Intranasal administration in mice revealed (a) diffusion of neurotrophins in the striatum and cortex, and (b) MPTP intoxication neuroprotection in the substantia nigra and striatum and the absence of neuroinflammation. These dedicated heat-treated PPLs can be a safe and valuable candidate for a therapeutic strategy for PD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical disability, life stress, and psychosocial adjustment in multiple sclerosis.

PubMed

Zeldow, P B; Pavlou, M

1984-02-01

Eighty-one outpatients with diagnosed multiple sclerosis were studied in an effort to examine the relative contributions of physical health status, life stress, duration of illness, age, sex, marital status, and social class on various aspects of personal and interpersonal functioning. Stepwise multiple regression analyses were performed to identify the most significant discriminators of the seven psychosocial measures. Physical health status exerted the broadest influence, affecting personal efficiency and well-being, capacity for independent thought and action, self-confidence, self-reliance, and number of meaningful social contacts. Life stress was associated with lowered personal efficiency and sense of well-being. Duration of illness and the demographic variables had few or no effects on psychosocial adjustment. Discussion contrasts the present findings with others in the rehabilitation literature and specifies certain limitations of the study's design.

Clinical Uses of Probiotics.

PubMed

Islam, Saif Ul

2016-02-01

Probiotics are live nonpathogenic microorganisms. Many of these microorganisms are part of the normal human gut flora, where they live in a symbiotic relationship. Probiotics have been used to treat gastrointestinal (GI) and non-GI medical conditions. However, the data supporting their use are often conflicting, especially for non-GI-associated illnesses. The strongest evidence supporting the use of probiotics is related to the treatment of acute diarrhea and pouchitis. Atopic eczema in children and genitourinary infections are the only non-GI-related medical conditions where probiotics may have some beneficial effects. Product selection and dosing are not the same in all conditions, and the beneficial effects of each probiotic strain cannot be generalized.The purpose of this article is to provide most recent information about probiotics and its uses. In contrast with previously published reviews on probiotics, we also discuss the composition of various products (Table 1), indications for their use (Table 2), product selection, and dosing of probiotics.Probiotics are safe and appear to exert some beneficial effects in GI-related illnesses. The use of probiotics in non-GI illnesses is not sufficiently supported by current data.

The social meaning of disability: a reflection on categorisation, stigma and identity.

PubMed

Grue, Jan

2016-07-01

As disability becomes an ever more salient concept in international political and legal discourse, its social meaning must be better understood. Traditionally defined in medical terms and as an individual problem, it has for the last several decades increasingly become a socio-politically defined phenomenon. Disability pride has emerged as a social movement patterned after ethnic minority and sexual orientation movements. The one billion people who count as disabled nevertheless have illnesses and impairments that are largely understood as medical problems. Medicine continues to exert great influence on the social meaning of disability in general and the social valuation of various illnesses and impairments in particular. Whereas specific conditions may be socially valued, the overall category and label of disability connotes marginality and stigma. Under these conditions, disability policy, which ought to be a universal concern, risks being construed as a marginal and special-interest issue rather than a broadly relevant topic; this has potentially negative consequences for the majority of disabled people. © 2016 Foundation for the Sociology of Health & Illness.

Clinical Uses of Probiotics

PubMed Central

Islam, Saif Ul

2016-01-01

Abstract Probiotics are live nonpathogenic microorganisms. Many of these microorganisms are part of the normal human gut flora, where they live in a symbiotic relationship. Probiotics have been used to treat gastrointestinal (GI) and non-GI medical conditions. However, the data supporting their use are often conflicting, especially for non-GI-associated illnesses. The strongest evidence supporting the use of probiotics is related to the treatment of acute diarrhea and pouchitis. Atopic eczema in children and genitourinary infections are the only non-GI-related medical conditions where probiotics may have some beneficial effects. Product selection and dosing are not the same in all conditions, and the beneficial effects of each probiotic strain cannot be generalized. The purpose of this article is to provide most recent information about probiotics and its uses. In contrast with previously published reviews on probiotics, we also discuss the composition of various products (Table 1), indications for their use (Table 2), product selection, and dosing of probiotics. Probiotics are safe and appear to exert some beneficial effects in GI-related illnesses. The use of probiotics in non-GI illnesses is not sufficiently supported by current data. PMID:26844491

Wet-bulb globe temperature (WBGT)--its history and its limitations.

PubMed

Budd, Grahame M

2008-01-01

Wet-bulb globe temperature (WBGT) is nowadays the most widely used index of heat stress, yet many users appear to be unaware of its history and its limitations. HISTORY OF WBGT: WBGT was invented and first used during the 1950s as one element in a successful campaign to control serious outbreaks of heat illness in training camps of the United States Army and Marine Corps. Control measures based on air temperature and humidity, and applied to all trainees alike, had proved effective but had entailed excessive compliance costs in the form of lost training time. New control measures introduced in 1956 further reduced heat illness and also lost fewer training hours. Crucial innovations were (1) replacing the temperature and humidity measurements with WBGT, which additionally responds to sun and wind, (2) using epidemiologic analyses of casualty records to identify hazardous levels of WBGT and vulnerable trainees, and (3) protecting the most vulnerable trainees by suspending drill at lower levels of WBGT, and by improving their heat tolerance in special conditioning platoons. This campaign has considerable relevance to the prevention of heat illness in sport. LIMITATIONS OF WBGT: WBGT's most serious limitation is that environments at a given level of the index are more stressful when the evaporation of sweat is restricted (by high humidity or low air movement) than when evaporation is free. As with all indices that integrate elements of the thermal environment, interpretation of the observed levels of WBGT requires careful evaluation of people's activity, clothing, and many other factors, all of which can introduce large errors into any predictions of adverse effects. Moreover, the accuracy of WBGT is being eroded by measurement errors associated with the omission of the globe temperature, with non-standard instrumentation, and with unsatisfactory calibration procedures. Because of the above limitations WBGT can provide only a general guide to the likelihood of adverse effects of heat. A much clearer assessment can be obtained by measuring the individual elements of the thermal environment, and using those measurements to estimate the requirement for evaporative cooling, the likelihood of achieving it, and more accurate and comprehensive indices of heat stress.

Economic Burden of Hospitalizations for Heat-Related Illnesses in the United States, 2001-2010.

PubMed

Schmeltz, Michael T; Petkova, Elisaveta P; Gamble, Janet L

2016-09-08

Understanding how heat waves affect morbidity and mortality, as well as the associated economic costs, is essential for characterizing the human health impacts of extreme heat under a changing climate. Only a handful of studies have examined healthcare costs associated with exposures to high temperatures. This research explores costs associated with hospitalizations for heat-related illness (HRI) in the United States using the 2001 to 2010 Nationwide Inpatient Sample (NIS). Descriptive statistics of patient data for HRI hospitalizations were examined and costs of hospitalizations were reported using the all-payer inpatient cost-to-charge ratio. Costs were examined using a log-gamma model with patient and hospital characteristics included as fixed effects. Adjusted mean costs were then compared across racial groups. The mean costs of HRI hospitalizations were higher among racial/ethnic minorities compared to Whites, who accounted for almost 65% of all HRI hospitalizations. Observed differences in costs based on income, insurance, and gender were also significant. These results suggest that these populations are suffering disproportionately from health inequity, thus, they could shoulder greater disease and financial burdens due to climate change. These findings may have important implications in understanding the economic impact public health planning and interventions will have on preventing hospitalizations related to extreme heat.

National Athletic Trainers' Association Position Statement: Fluid Replacement for Athletes.

ERIC Educational Resources Information Center

Case, Douglas J.; Armstrong, Lawrence E.; Hillman, Susan K.; Montain, Scott J.; Reiff, Ralph V.; Rich, Brent S. E.; Roberts, William O.; Stone, Jennifer A.

2000-01-01

Presents recommendations from the National Athletic Trainers Association for optimizing the fluid replacement practices of athletes, explaining that dehydration can compromise athletic performance and increase the risk of exertional heat injury. Athletes must be educated about the risks of dehydration and overhydration. They must learn fluid…

Athletic Training Educators' Pedagogical Strategies for Preparing Students to Address Sudden Death in Sport

ERIC Educational Resources Information Center

Mazerolle, Stephanie M.; Pagnotta, Kelly D.; Salvatore, Anthony C.; Casa, Douglas J.

2013-01-01

Context: Educational training programs both impart knowledge and allow students to practice skills to gain clinical competence. Objective: Understand the educational training provided to athletic training students regarding sudden death in sport beyond exertional heat stroke. Design: An exploratory, qualitative study using telephone interviews and…

Validation of Core Temperature Estimation Algorithm

DTIC Science & Technology

2016-01-20

thermoregulation that can affect heart rate. These factors include diet , caffeine, sleep, and psychological stress. Of the 47,549 data points that...O’Connor and R. Huggins, "Exertional Heat Stroke: New Concepts Regarding Cause and Care," Current Sports Medicine Reports, pp. 115–123, 2012. 3. B. Ely

Determining Atmospheric Pressure Using a Water Barometer

ERIC Educational Resources Information Center

Lohrengel, C. Frederick, II; Larson, Paul R.

2012-01-01

The atmosphere is an envelope of compressible gases that surrounds Earth. Because of its compressibility and nonuniform heating by the Sun, it is in constant motion. The atmosphere exerts pressure on Earth's surface, but that pressure is in constant flux. This experiment allows students to directly measure atmospheric pressure by measuring the…

Mapping rural community and dairy cow heat stress in Southern Ontario: A common geographic pattern from 2010 to 2012.

PubMed

Bishop-Williams, Katherine E; Berke, Olaf; Pearl, David L; Kelton, David F

2016-07-03

Climate change has increased the occurrence of heat waves, causing heat stress among humans and livestock, with potentially fatal consequences. Heat stress maps provide information about related health risks and insight for control strategies. Weather data were collected throughout Southern Ontario, and the heat stress index (HSI) was estimated for 2010-2012. Geostatistical kriging was applied to map heat stress, heat waves, and control periods. Average HSI for each period ranged from 55 to 78 during control periods, and from 65 to 84 during heat waves, surpassing levels where morbidity is known to increase substantially. Heat stress followed a temporally consistent geographic pattern. HSI maps indicate high-risk areas for heat-related illness and indicate areas where agriculture and human health may be at increased risk in future.

Inverse problems and optimal experiment design in unsteady heat transfer processes identification

NASA Technical Reports Server (NTRS)

Artyukhin, Eugene A.

1991-01-01

Experimental-computational methods for estimating characteristics of unsteady heat transfer processes are analyzed. The methods are based on the principles of distributed parameter system identification. The theoretical basis of such methods is the numerical solution of nonlinear ill-posed inverse heat transfer problems and optimal experiment design problems. Numerical techniques for solving problems are briefly reviewed. The results of the practical application of identification methods are demonstrated when estimating effective thermophysical characteristics of composite materials and thermal contact resistance in two-layer systems.

[Pathophysiology of heat illness].

PubMed

Aruga, Tohru; Miyake, Yasufumi

2012-06-01

Human core temperature is strictly controlled by mechanism of radiation, conduction, convection, and evaporation from skin surface. Serial hot and humid climate induces dehydration which interferes heat pump-out from the body. Heart dysfunction is the third factor to rise body temperature. Hyperthermia and hypo-perfusion caused by dehydration and heart failure deteriorate specific organ functions, i.e. central nervous system, liver and renal functions and coagulation system. Disseminated intravascular coagulopathy is one of the standard indicators of severity and mortality of heat stroke.

Life-threatening heat stroke presenting with ST elevations: a report of consecutive cases during the heat wave in Austria in July 2013.

PubMed

Lassnig, Elisabeth; Dinkhauser, Patrick; Maurer, Edwin; Eber, Bernd

2014-08-01

Heat stroke is a life-threatening condition due to an acute thermoregulatory failure during exposure to high environmental temperatures. We report a series of four cases (three exertional, one classic heat stroke) during the heat wave of July 2013 in Austria. All of them presented with a core temperature > 41 °C, central nervous dysfunction, acute respiratory and renal failure, disseminated intravascular coagulation, rhabdomyolysis, and severe electrocardiographic changes, two cases even mimicking ST-elevation myocardial infarction. The patients were cooled to normal temperature with the "Arctic sun" external cooling system within hours. Electrocardiographic changes resolved quickly. All patients primarily recovered from multiple organ dysfunction and could be discharged from intensive care unit. Unfortunately, the two elder patients died 1 week and 5 weeks later because of late complications.

Initiation of the Immune Response by Extracellular Hsp72: Chaperokine Activity of Hsp72

PubMed Central

Asea, Alexzander

2007-01-01

Heat shock proteins exert their beneficial effects via basically two modes of action depending on their relative location within the host. Intracellular heat shock proteins found within cells serve a cytoprotective role by chaperoning naïve, misfolded and/or denatured proteins in response to stressful stimuli by a process known as the stress response. However, stressful stimuli also induce the release of intracellular heat shock proteins into the extracellular milieu and circulation. The extracellular heat shock protein proteins serve a cytostimulatory role by initiating immune responses designed to fend off microbial infection and destroy neoplastic transformed cells. This review will briefly cover recent advances into elucidating the mechanism(s) by which stress induces the release of heat shock proteins into the circulation, how it initiates immune responses and suggest the possible biological significance of circulating Hsp to the host. PMID:17502920

Initiation of the Immune Response by Extracellular Hsp72: Chaperokine Activity of Hsp72.

PubMed

Asea, Alexzander

2006-08-01

Heat shock proteins exert their beneficial effects via basically two modes of action depending on their relative location within the host. Intracellular heat shock proteins found within cells serve a cytoprotective role by chaperoning naïve, misfolded and/or denatured proteins in response to stressful stimuli by a process known as the stress response. However, stressful stimuli also induce the release of intracellular heat shock proteins into the extracellular milieu and circulation. The extracellular heat shock protein proteins serve a cytostimulatory role by initiating immune responses designed to fend off microbial infection and destroy neoplastic transformed cells. This review will briefly cover recent advances into elucidating the mechanism(s) by which stress induces the release of heat shock proteins into the circulation, how it initiates immune responses and suggest the possible biological significance of circulating Hsp to the host.

Microbial survival in space shuttle crash

PubMed Central

McLean, Robert J.C.; Welsh, Allana K.; Casasanto, Valerie A.

2011-01-01

A slow growing, heat resistant bacterium, identified by 16S rRNA gene sequencing as Microbispora sp., was recovered from the wreckage of the ill-fated space shuttle Columbia (STS-107). As this organism survived disintegration of the space craft, heat of reentry, and impact, it supports the possibility of a natural mechanism for the interplanetary spread of life by meteorites. PMID:21804644

A Heat Warning System to Reduce Heat Illness in San Diego County

NASA Astrophysics Data System (ADS)

Tardy, A. O.; Corcus, I.; Guirguis, K.; Gershunov, A.; Basu, R.; Stepanski, B.

2016-12-01

The National Weather Service (NWS) has issued official heat alerts to the public and decision making partners for many years by developing a single criterion or regional criteria from heat indices which combine temperature and humidity. The criteria have typically relied on fixed thresholds and did not consider impact from a particular heat episode, nor did it factor seasonality, population acclimatization, or impacts on the most vulnerable subgroups. In 2013, the NWS San Diego office began modifying their criteria to account for local climatology with much less dependence on humidity or the heat index. These local changes were based on initial findings from the California Department of Public Health, EpiCenter California Injury Data Online system (EPIC), which document heat health impacts. The Scripps Institution of Oceanography (SIO) in collaboration with the California Environmental Protection Agency's Office of Environmental Health Hazard Assessment and the NWS completed a study of hospital visits during heat waves in California showing significant health impacts occurred in the past when no regional heat warning was issued. Therefore, the results supported the need for an exploratory project to implement significant modification of the traditional local criteria. To understand the impacts of heat on community health, medical outcome data were provided by the County of San Diego Emergency Medical Services Branch (EMS), which is provided by the County's Public Health Officer to monitor heat-related illness and injury daily during specific heat episodes. The data were combined with SIO research to inform the modification of local NWS heat criteria and establish trigger points to pilot new procedures for the issuance of heat alerts. Finally, procedures were customized for each of the county health departments in the NWS area of responsibility across extreme southwest California counties in collaboration with their Office of Emergency Services (OES). The collaboration was the development of a local Heat Health Impact and Public Notification System prototype. This system incorporates better temperature thresholds defined relative to local climate, levels of heat related responses and activation, as well as a standardized alerting terminology for public notifications.

Heat or Cold: Which One Exerts Greater Deleterious Effects on Health in a Basin Climate City? Impact of Ambient Temperature on Mortality in Chengdu, China.

PubMed

Cui, Yan; Yin, Fei; Deng, Ying; Volinn, Ernest; Chen, Fei; Ji, Kui; Zeng, Jing; Zhao, Xing; Li, Xiaosong

2016-12-10

Background : Although studies from many countries have estimated the impact of ambient temperature on mortality, few have compared the relative impacts of heat and cold on health, especially in basin climate cities. We aimed to quantify the impact of ambient temperature on mortality, and to compare the contributions of heat and cold in a large basin climate city, i.e., Chengdu (Sichuan Province, China); Methods : We estimated the temperature-mortality association with a distributed lag non-linear model (DLNM) with a maximum lag-time of 21 days while controlling for long time trends and day of week. We calculated the mortality risk attributable to heat and cold, which were defined as temperatures above and below an "optimum temperature" that corresponded to the point of minimum mortality. In addition, we explored effects of individual characteristics; Results : The analysis provides estimates of the overall mortality burden attributable to temperature, and then computes the components attributable to heat and cold. Overall, the total fraction of deaths caused by both heat and cold was 10.93% (95%CI: 7.99%-13.65%). Taken separately, cold was responsible for most of the burden (estimate 9.96%, 95%CI: 6.90%-12.81%), while the fraction attributable to heat was relatively small (estimate 0.97%, 95%CI: 0.46%-2.35%). The attributable risk (AR) of respiratory diseases was higher (19.69%, 95%CI: 14.45%-24.24%) than that of cardiovascular diseases (11.40%, 95%CI: 6.29%-16.01%); Conclusions : In Chengdu, temperature was responsible for a substantial fraction of deaths, with cold responsible for a higher proportion of deaths than heat. Respiratory diseases exert a larger effect on death than other diseases especially on cold days. There is potential to reduce respiratory-associated mortality especially among the aged population in basin climate cities when the temperature deviates beneath the optimum. The result may help to comprehensively assess the impact of ambient temperature in basin cities, and further facilitate an appropriate estimate of the health consequences of various climate-change scenarios.

Heat or Cold: Which One Exerts Greater Deleterious Effects on Health in a Basin Climate City? Impact of Ambient Temperature on Mortality in Chengdu, China

PubMed Central

Cui, Yan; Yin, Fei; Deng, Ying; Volinn, Ernest; Chen, Fei; Ji, Kui; Zeng, Jing; Zhao, Xing; Li, Xiaosong

2016-01-01

Background: Although studies from many countries have estimated the impact of ambient temperature on mortality, few have compared the relative impacts of heat and cold on health, especially in basin climate cities. We aimed to quantify the impact of ambient temperature on mortality, and to compare the contributions of heat and cold in a large basin climate city, i.e., Chengdu (Sichuan Province, China); Methods: We estimated the temperature-mortality association with a distributed lag non-linear model (DLNM) with a maximum lag-time of 21 days while controlling for long time trends and day of week. We calculated the mortality risk attributable to heat and cold, which were defined as temperatures above and below an “optimum temperature” that corresponded to the point of minimum mortality. In addition, we explored effects of individual characteristics; Results: The analysis provides estimates of the overall mortality burden attributable to temperature, and then computes the components attributable to heat and cold. Overall, the total fraction of deaths caused by both heat and cold was 10.93% (95%CI: 7.99%–13.65%). Taken separately, cold was responsible for most of the burden (estimate 9.96%, 95%CI: 6.90%–12.81%), while the fraction attributable to heat was relatively small (estimate 0.97%, 95%CI: 0.46%–2.35%). The attributable risk (AR) of respiratory diseases was higher (19.69%, 95%CI: 14.45%–24.24%) than that of cardiovascular diseases (11.40%, 95%CI: 6.29%–16.01%); Conclusions: In Chengdu, temperature was responsible for a substantial fraction of deaths, with cold responsible for a higher proportion of deaths than heat. Respiratory diseases exert a larger effect on death than other diseases especially on cold days. There is potential to reduce respiratory-associated mortality especially among the aged population in basin climate cities when the temperature deviates beneath the optimum. The result may help to comprehensively assess the impact of ambient temperature in basin cities, and further facilitate an appropriate estimate of the health consequences of various climate-change scenarios. PMID:27973401

Transient boiling in two-phase helium natural circulation loops

NASA Astrophysics Data System (ADS)

Furci, H.; Baudouy, B.; Four, A.; Meuris, C.

2014-01-01

Two-phase helium natural circulation loops are used for cooling large superconducting magnets, as CMS for LHC. During normal operation or in the case of incidents, transients are exerted on the cooling system. Here a cooling system of this type is studied experimentally. Sudden power changes are operated on a vertical-heated-section natural convection loop, simulating a fast increase of heat deposition on magnet cooling pipes. Mass flow rate, heated section wall temperature and pressure drop variations are measured as a function of time, to assess the time behavior concerning the boiling regime according to the values of power injected on the heated section. The boiling curves and critical heat flux (CHF) values have been obtained in steady state. Temperature evolution has been observed in order to explore the operating ranges where heat transfer is deteriorated. Premature film boiling has been observed during transients on the heated section in some power ranges, even at appreciably lower values than the CHF. A way of attenuating these undesired temperature excursions has been identified through the application of high enough initial heating power.

Heat stress intervention research in construction: gaps and recommendations.

PubMed

Yang, Yang; Chan, Albert Ping-Chuen

2017-06-08

Developing heat stress interventions for construction workers has received mounting concerns in recent years. However, limited efforts have been exerted to elaborate the rationale, methodology, and practicality of heat stress intervention in the construction industry. This study aims to review previous heat stress intervention research in construction, to identify the major research gaps in methodological issues, and to offer detailed recommendations for future studies. A total of 35 peer-reviewed journal papers have been identified to develop administrative, environmental or personal engineering interventions to safeguard construction workers. It was found that methodological limitations, such as arbitrary sampling methods and unreliable instruments, could be the major obstacle in undertaking heat stress intervention research. To bridge the identified research gaps, this study then refined a research framework for conducting heat stress intervention studies in the construction industry. The proposed research strategy provides researchers and practitioners with fresh insights into expanding multidisciplinary research areas and solving practical problems in the management of heat stress. The proposed research framework may foster the development of heat stress intervention research in construction, which further aids researchers, practitioners, and policymakers in formulating proper intervention strategies.

FUEL ROD CLUSTERS

DOEpatents

Schultz, A.B.

1959-08-01

A cluster of nuclear fuel rods and a tubular casing therefor through which a coolant flows in heat-exchange contact with the fuel rods is described. The fuel rcds are held in the casing by virtue of the compressive force exerted between longitudinal ribs of the fuel rcds and internal ribs of the casing or the internal surfaces thereof.

Implementation of the Montreal heat response plan during the 2010 heat wave.

PubMed

Price, Karine; Perron, Stéphane; King, Norman

2013-02-11

The objective of this paper is to describe Montreal's heat response plan and its application during the July 2010 heat wave. The Montreal heat response plan is designed to ensure the surveillance of weather and health indicators during the summer season and to coordinate actions to be undertaken during this period to reduce morbidity and mortality due to heat, particularly when weather thresholds are reached or an increase in health indicators is observed. It was developed to coordinate and apply intervention measures on the Island of Montreal and has been in effect since 2004. In the beginning of July 2010, Montreal experienced a heat wave that lasted 5 days. During this period, health indicators such as total mortality, prehospital emergency transports, calls to the health information line and hospital admissions were monitored by the Montreal public health surveillance system. The decision to implement emergency interventions and actions performed by regional and local public health and municipal partners (intervention level) was made following attainment of a predetermined weather threshold and increases in health indicators. The significant increase in daily observed mortality from all causes and in particular people dying at home or in the community prompted the Director of public health to conduct a chart review of all people deceased from July 5 to July 11, 2010 to determine cause of death and underlying health conditions. During the heat wave, there were 304 reported deaths from all causes in Montreal residents, of which 106 were probably or possibly heat-related. Major underlying health conditions in heat-related deaths included cardiovascular problems and mental health illness. Furthermore, in the case of people with mental illness who died during the heat wave, the chart review revealed that many were contacted 24 hours prior to their death by health care professionals, family members, neighbours or friends. Following the 2010 heat wave, the Montreal heat response plan and heat surveillance system were updated to include initiatives to better communicate preventive measures to the vulnerable populations and to intervene earlier during a heat wave.

Promising novel therapy with hydrogen gas for emergency and critical care medicine.

PubMed

Sano, Motoaki; Suzuki, Masaru; Homma, Koichiro; Hayashida, Kei; Tamura, Tomoyoshi; Matsuoka, Tadashi; Katsumata, Yoshinori; Onuki, Shuko; Sasaki, Junichi

2018-04-01

It has been reported that hydrogen gas exerts a therapeutic effect in a wide range of disease conditions, from acute illness such as ischemia-reperfusion injury, shock, and damage healing to chronic illness such as metabolic syndrome, rheumatoid arthritis, and neurodegenerative diseases. Antioxidant and anti-inflammatory properties of hydrogen gas have been proposed, but the molecular target of hydrogen gas has not been identified. We established the Center for Molecular Hydrogen Medicine to promote non-clinical and clinical research on the medical use of hydrogen gas through industry-university collaboration and to obtain regulatory approval of hydrogen gas and hydrogen medical devices (http://www.karc.keio.ac.jp/center/center-55.html). Studies undertaken by the Center have suggested possible therapeutic effects of hydrogen gas in relation to various aspects of emergency and critical care medicine, including acute myocardial infarction, cardiopulmonary arrest syndrome, contrast-induced acute kidney injury, and hemorrhagic shock.

[Illness, culture and religion--issues of intercultural medical ethics and nursing ethics].

PubMed

Körtner, Ulrich H J

2007-01-01

Should modern medicine be allowed to do what it is capable of? And what role are religious norms and attitudes to play in both the medical course of life and the bioethical discourse of modern societies? Questions like these are subject of current intercultural medical and nursing ethics. Religious attitudes not only influence the cultural and political surroundings of medical research but also exert a practical influence on the health and illness attitudes of the individual. Coming before moral judgement should be the endeavour to understand one's counterpart, namely the patient, and his/her socio-cultural background. The question to be answered is how therapy and nursing can best be applied within the given socio-cultural framework without those responsible denying their own medical premises or their own concepts of nursing. Intercultural medical and nursing ethics provide an important contribution to the current debate on integration.

Mesmer minus magic: hypnosis and modern medicine.

PubMed

Spiegel, David

2002-10-01

The implications and effects of the French commission that passed judgment on Mesmer's work is examined in light of the pioneering role of hypnosis as the first Western conception of a psychotherapy, the ancient philosophical debate between idealism and empiricism, and the conflict in modern medicine between biotechnological emphasis on cure and the need for care as many previously terminal illnesses are converted to chronic diseases. The panel's report is interpreted as negative about the literal theory of animal magnetism but actually supportive of the potential therapeutic power of suggestion and "positive thinking." This aspect of hypnosis is described as a forerunner of modern cognitive therapies of depression and other illnesses. The panel exerted a constructive effect in applying scientific method and rigorous evaluation to hypnotic treatment, an application of Enlightenment philosophy that presaged the Flexner era in modern medicine. Both hypnosis and medicine ultimately benefited.

Climate Change and the Emergent Epidemic of CKD from Heat Stress in Rural Communities: The Case for Heat Stress Nephropathy

PubMed Central

Glaser, Jason; Lemery, Jay; Rajagopalan, Balaji; Diaz, Henry F.; García-Trabanino, Ramón; Taduri, Gangadhar; Madero, Magdalena; Amarasinghe, Mala; Abraham, Georgi; Anutrakulchai, Sirirat; Jha, Vivekanand; Stenvinkel, Peter; Roncal-Jimenez, Carlos; Lanaspa, Miguel A.; Correa-Rotter, Ricardo; Sheikh-Hamad, David; Burdmann, Emmanuel A.; Andres-Hernando, Ana; Milagres, Tamara; Weiss, Ilana; Kanbay, Mehmet; Wesseling, Catharina; Sánchez-Lozada, Laura Gabriela

2016-01-01

Climate change has led to significant rise of 0.8°C–0.9°C in global mean temperature over the last century and has been linked with significant increases in the frequency and severity of heat waves (extreme heat events). Climate change has also been increasingly connected to detrimental human health. One of the consequences of climate-related extreme heat exposure is dehydration and volume loss, leading to acute mortality from exacerbations of pre-existing chronic disease, as well as from outright heat exhaustion and heat stroke. Recent studies have also shown that recurrent heat exposure with physical exertion and inadequate hydration can lead to CKD that is distinct from that caused by diabetes, hypertension, or GN. Epidemics of CKD consistent with heat stress nephropathy are now occurring across the world. Here, we describe this disease, discuss the locations where it appears to be manifesting, link it with increasing temperatures, and discuss ongoing attempts to prevent the disease. Heat stress nephropathy may represent one of the first epidemics due to global warming. Government, industry, and health policy makers in the impacted regions should place greater emphasis on occupational and community interventions. PMID:27151892

The effect of fever, febrile illnesses, and heat exposures on the risk of neural tube defects in a Texas-Mexico border population.

PubMed

Suarez, Lucina; Felkner, Marilyn; Hendricks, Kate

2004-10-01

Hyperthermia produces neural tube defects (NTDs) in a variety of animal species. Elevated maternal body temperatures may also place the developing human embryo at risk. We examined the relation between maternal hyperthermia and the development of NTDs in a high-risk Mexican-American population. Case-women were Mexican-American women with NTD-affected pregnancies who resided and delivered in any of the 14 Texas counties bordering Mexico, during 1995-2000. Control-women were randomly selected from study area residents delivering normal live births, frequency-matched to cases by hospital and year. Information on maternal fevers, febrile illnesses, exposures to heat generated from external sources, and hyperthermia-inducing activities was gathered through in-person interviews, conducted about six weeks postpartum. The risk effect (OR) associated with maternal fever in the first trimester, compared to no fever, was 2.9 (95% CI, 1.5-5.7). Women taking fever-reducing medications showed a lower risk effect (OR, 2.4; 95% CI, 1.0-5.6) than those who did not (OR, 3.8; 95% CI, 1.4-10.9). First-trimester maternal exposures to heat devices such as hot tubs, saunas, or electric blankets were associated with an OR of 3.6 (95% CI, 1.1-15.9). Small insignificant effects were observed for activities such as cooking in a hot kitchen (OR, 1.6; 95% CI, 1.0-2.6) and working or exercising in the sun (OR, 1.4; 95% CI, 0.9-2.2). Maternal hyperthermia increases the risk for NTD-affected offspring. Women intending to become pregnant should avoid intense heat exposures, carefully monitor and manage their febrile illnesses, and routinely consume folic acid supplements. (c) 2004 Wiley-Liss, Inc.

Interleukin-6 Responses to Water Immersion Therapy After Acute Exercise Heat Stress: A Pilot Investigation

PubMed Central

Lee, Elaine C.; Watson, Greig; Casa, Douglas; Armstrong, Lawrence E.; Kraemer, William; Vingren, Jakob L.; Spiering, Barry A.; Maresh, Carl M.

2012-01-01

Context Cold-water immersion is the criterion standard for treatment of exertional heat illness. Cryotherapy and water immersion also have been explored as ergogenic or recovery aids. The kinetics of inflammatory markers, such as interleukin-6 (IL-6), during cold-water immersion have not been characterized. Objective To characterize serum IL-6 responses to water immersion at 2 temperatures and, therefore, to initiate further research into the multidimensional benefits of immersion and the evidence-based selection of specific, optimal immersion conditions by athletic trainers. Design Controlled laboratory study. Setting Human performance laboratory Patients or Other Participants Eight college-aged men (age = 22 ± 3 years, height = 1.76 ± 0.08 m, mass = 77.14 ± 9.77 kg, body fat = 10% ± 3%, and maximal oxygen consumption = 50.48 ± 4.75 mL·kg−1·min−1). Main Outcome Measures Participants were assigned randomly to receive either cold (11.70°C ± 2.02°C, n = 4) or warm (23.50°C ± 1.00°C, n = 4) water-bath conditions after exercise in the heat (temperature = 37°C, relative humidity = 52%) for 90 minutes or until volitional cessation. Results Whole-body cooling rates were greater in the cold water-bath condition for the first 6 minutes of water immersion, but during the 90-minute, postexercise recovery, participants in the warm and cold water-bath conditions experienced similar overall whole-body cooling. Heart rate responses were similar for both groups. Participants in the cold water-bath condition experienced an overall slight increase (30.54% ± 77.37%) in IL-6 concentration, and participants in the warm water-bath condition experienced an overall decrease (−69.76% ± 15.23%). Conclusions We have provided seed evidence that cold-water immersion is related to subtle IL-6 increases from postexercise values and that warmer water-bath temperatures might dampen this increase. Further research will elucidate any anti-inflammatory benefit associated with water-immersion treatment and possible multidimensional uses of cooling therapies. PMID:23182014

Effects of caffeine on endurance capacity and psychological state in young females and males exercising in the heat.

PubMed

Suvi, Silva; Timpmann, Saima; Tamm, Maria; Aedma, Martin; Kreegipuu, Kairi; Ööpik, Vahur

2017-01-01

Acute caffeine ingestion is considered effective in improving endurance capacity and psychological state. However, current knowledge is based on the findings of studies that have been conducted on male subjects mainly in temperate environmental conditions, but some physiological and psychological effects of caffeine differ between the sexes. The purpose of this study was to compare the physical performance and psychological effects of caffeine in young women and men exercising in the heat. Thirteen male and 10 female students completed 2 constant-load walks (60% of thermoneutral peak oxygen consumption on a treadmill until volitional exhaustion) in a hot-dry environment (air temperature, 42 °C; relative humidity, 20%) after caffeine (6 mg·kg -1 ) and placebo (wheat flour) ingestion in a double-blind, randomly assigned, crossover manner. Caffeine, compared with placebo, induced greater increases (p < 0.05) in heart rate (HR) and blood lactate concentrations in both males and females but had no impact on rectal or skin temperatures or on walking time to exhaustion in subjects of either gender. Caffeine decreased (p < 0.05) ratings of perceived exertion and fatigue in males, but not in females. In females, but not in males, a stronger belief that they had been administered caffeine was associated with a shorter time to exhaustion. In conclusion, acute caffeine ingestion increases HR and blood lactate levels during exercise in the heat, but it has no impact on thermoregulation or endurance capacity in either gender. Under exercise-heat stress, caffeine reduces ratings of perceived exertion and fatigue in males but not in females.

Drink temperature influences fluid intake and endurance capacity in men during exercise in a hot, dry environment.

PubMed

Mündel, Toby; King, Jenny; Collacott, Esther; Jones, David A

2006-09-01

The effect of different drink temperatures on the perception of exertion and exercise endurance has not been extensively investigated. Consequently, the purpose of the present study was to examine the effect of drink temperature on fluid intake and endurance during cycling in the heat. Eight healthy, non-acclimated males (26 +/- 7 years; maximum oxygen uptake, 54 +/- 5 ml kg(-1) min(-1); mean +/- S.D.) cycled to exhaustion at 34 degrees C and at 65% of their peak aerobic power, consuming a drink at either 19 degrees C (CON) or 4 degrees C (COLD). Six of the eight subjects cycled for longer during COLD, with exhaustion occurring at 62 +/- 4 min, compared to 55 +/- 4 min for CON (P < 0.05; mean +/- S.E.M.). Subjects consumed significantly more fluid during COLD compared to CON (1.3 +/- 0.3 l h(-1) compared to 1.0 +/- 0.2 l h(-1); P < 0.05). Heart rate tended to be lower by approximately 5 beats min(-1) during COLD, and rectal temperature during the second half of the exercise period was approximately 0.25 degrees C lower during the COLD trial; however, these trends were not significant (P = 0.08 and P = 0.07, respectively). No differences were observed between trials for ventilation, concentrations of prolactin, glucose and lactate or perceived exertion. It is concluded that a drink at 4 degrees C during exercise in the heat enhances fluid consumption and improves endurance by acting as a heat sink, attenuating the rise in body temperature and therefore reducing the effects of heat stress.

A gastrointestinal anti-infectious biotherapeutic agent: the heat-treated Lactobacillus LB

PubMed Central

Liévin-Le Moal, Vanessa

2016-01-01

Experimental in vitro and in vivo studies support the hypothesis that heat-treated, lyophilized Lactobacillus acidophilus LB cells and concentrated, neutralized spent culture medium conserve the variety of pharmacological, antimicrobial activities of the live probiotic strain against several infectious agents involved in well-established acute and persistent watery diarrhoea and gastritis. Heat-treated cells and heat-stable secreted molecules trigger multiple strain-specific activities explaining the therapeutic efficacy of L. acidophilus LB. This review discusses the current body of knowledge on the antimicrobial mechanisms of action exerted by L. acidophilus LB demonstrated in in vitro and in vivo experimental studies, and the evidence for the therapeutic efficacy of this anti-infectious biotherapeutic agent proved in randomized clinical trials for the treatment of acute and persistent watery diarrhoea associated with several intestinal infectious diseases in humans. PMID:26770268

The prevalence and preventive measures of the respiratory illness among Malaysian pilgrims in 2013 Hajj season.

PubMed

Hashim, Suhana; Ayub, Zeti N; Mohamed, Zeehaida; Hasan, Habsah; Harun, Azian; Ismail, Nabilah; Rahman, Zaidah A; Suraiya, Siti; Naing, Nyi Nyi; Aziz, Aniza A

2016-02-01

Respiratory illness continues to exert a burden on hajj pilgrims in Makkah. The purpose of this study is to determine the prevalence of respiratory illness and its associated factors among Malaysian hajj pilgrims in 2013 and to describe its preventive measures. A cross-sectional study was conducted in Makkah and Malaysia during the 2013 hajj season. A self-administered proforma on social demographics, previous experience of hajj or umrah, smoking habits, co-morbid illness and practices of preventive measures against respiratory illness were obtained. A total of 468 proforma were analysed. The prevalence of the respiratory illness was 93.4% with a subset of 78.2% fulfilled the criteria for influenza-like illness (ILI). Most of them (77.8%) had a respiratory illness of <2 weeks duration. Approximately 61.8% were administered antibiotics but only 2.1% of them had been hospitalized. Most of them acquired the infection after a brief stay at Arafat (81.2%). Vaccination coverages for influenza virus and pneumococcal disease were quite high, 65.2% and 59.4%, respectively. For other preventive measures practices, only 31.8% of them practiced good hand hygiene, ∼82.9% of pilgrims used surgical face masks, N95 face masks, dry towels, wet towels or veils as their face masks. Nearly one-half of the respondents (44.4%) took vitamins as their food supplement. Malaysian hajj pilgrims with previous experience of hajj (OR 0.24; 95% CI 0.10-0.56) or umrah (OR 0.19; 95% CI 0.07-0.52) and those who have practiced good hand hygiene (OR 0.35; 95% CI 0.16-0.79) were found to be significantly associated with lower risk of having respiratory illness. Otherwise, pilgrims who had contact with those with respiratory illness (OR 2.61; 95% CI 1.12-6.09) was associated with higher risk. The prevalence of respiratory illness remains high among Malaysian hajj pilgrims despite having some practices of preventive measures. All preventive measures which include hand hygiene, wearing face masks and influenza vaccination must be practiced together as bundle of care to reduce respiratory illness effectively. © The Author 2016. Published by Oxford University Press on behalf of International society of travel medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

L-arginine supplementation prevents increases in intestinal permeability and bacterial translocation in male Swiss mice subjected to physical exercise under environmental heat stress.

PubMed

Costa, Kátia Anunciação; Soares, Anne Danieli Nascimento; Wanner, Samuel Penna; Santos, Rosana das Graças Carvalho dos; Fernandes, Simone Odília Antunes; Martins, Flaviano dos Santos; Nicoli, Jacques Robert; Coimbra, Cândido Celso; Cardoso, Valbert Nascimento

2014-02-01

Dietary supplementation with l-arginine has been shown to improve the intestinal barrier in many experimental models. This study investigated the effects of arginine supplementation on the intestinal permeability and bacterial translocation (BT) induced by prolonged physical exercise under heat stress. Under anesthesia, male Swiss mice (5-wk-old) were implanted with an abdominal sensor to record their core body temperature (T(core)). After recovering from surgery, the mice were divided into 3 groups: a non-supplemented group that was fed the standard diet formulated by the American Institute of Nutrition (AIN-93G; control), a non-supplemented group that was fed the AIN-93G diet and subjected to exertional hyperthermia (H-NS), and a group supplemented with l-arginine at 2% and subjected to exertional hyperthermia (H-Arg). After 7 d of treatment, the H-NS and H-Arg mice were forced to run on a treadmill (60 min, 8 m/min) in a warm environment (34°C). The control mice remained at 24°C. Thirty min before the exercise or control trials, the mice received a diethylenetriamine pentaacetic acid (DTPA) solution labeled with technetium-99m ((99m)Tc-DTPA) or (99m)Tc-Escherichia coli by gavage to assess intestinal permeability and BT, respectively. The H-NS mice terminated the exercise with T(core) values of ∼40°C, and, 4 h later, presented a 12-fold increase in the blood uptake of (99m)Tc-DTPA and higher bacterial contents in the blood and liver than the control mice. Although supplementation with arginine did not change the exercise-induced increase in T(core), it prevented the increases in intestinal permeability and BT caused by exertional hyperthermia. Our results indicate that dietary l-arginine supplementation preserves the integrity of the intestinal epithelium during exercise under heat stress, acting through mechanisms that are independent of T(core) regulation.

Clinical Management of Heat-Related Illnesses

DTIC Science & Technology

2012-01-01

rhabdomyolysis and multiorgan dysfunction syndrome, and it may result in death from overwhelming cell necrosis caused by a lethal heat-shock exposure...complications such as rhabdomyolysis and multiorgan dysfunction syndrome, and it may result in death from overwhelming cell necrosis caused by a...acetaminophen lower Tco by normalizing the elevated hypothalamic set point that is caused by pyrogens; in heatstroke, the set point is normal, with

The epidemiology of occupational heat exposure in the United States: a review of the literature and assessment of research needs in a changing climate

NASA Astrophysics Data System (ADS)

Gubernot, Diane M.; Anderson, G. Brooke; Hunting, Katherine L.

2014-10-01

In recent years, the United States has experienced record-breaking summer heat. Climate change models forecast increasing US temperatures and more frequent heat wave events in the coming years. Exposure to environmental heat is a significant, but overlooked, workplace hazard that has not been well-characterized or studied. The working population is diverse; job function, age, fitness level, and risk factors to heat-related illnesses vary. Yet few studies have examined or characterized the incidence of occupational heat-related morbidity and mortality. There are no federal regulatory standards to protect workers from environmental heat exposure. With climate change as a driver for adaptation and prevention of heat disorders, crafting policy to characterize and prevent occupational heat stress for both indoor and outdoor workers is increasingly sensible, practical, and imperative.

Effectiveness of heat and moisture exchangers in preventing ventilator-associated pneumonia in critically ill patients: a meta-analysis.

PubMed

Menegueti, Mayra Gonçalves; Auxiliadora-Martins, Maria; Nunes, Altacílio Aparecido

2014-01-01

Patients may acquire ventilator-associated pneumonia (VAP) by aspirating the condensate that originates in the ventilator circuit upon use of a conventional humidifier. The bacteria that colonize the patients themselves can proliferate in the condensate and then return to the airways and lungs when the patient aspirates this contaminated material. Therefore, the use of HME might contribute to preventing pneumonia and lowering the VAP incidence. The aim of this study was to evaluate how the use of HME impacts the probability of VAP occurrence in critically ill patients. On the basis of the acronym "PICO" (Patient, Intervention, Comparison, Outcome), the question that guided this review was "Do critically ill patients under invasive mechanical ventilation present lower VAP incidence when they use HME as compared with HH?". Two of the authors of this review searched the databases PUBMED/Medline, The Cochrane Library, and Latin-American and Caribbean Literature in Health Sciences, LILACS independently; they used the following keywords: "heat and moisture exchanger", AND "heated humidifier", AND "ventilator-associated pneumonia prevention". This review included papers in the English language published from January 1990 to December 2012. This review included ten studies. Comparison between the use of HME and HH did not reveal any differences in terms of VAP occurrence (OR = 0.998; 95% CI: 0.778-1.281). Together, the ten studies corresponded to a total sample of 1077 and 953 patients in the HME and HH groups, respectively; heterogeneity among the investigations was low (I(2) < 50%). Information about the outcome mortality was available in only eight of the ten studies. The use of HME and HH did not afford different results in terms of mortality (OR = 1.09; 95% CI: 0.864-1.376). The total sample size was 884 and 762 patients, respectively. Heterogeneity among the studies was low (I(2) = 0.0%). Current meta-analysis was not sufficient to definitely exclude an associate between heat and moisture exchangers and VAP. Despite the methodological limitations found in selected clinical trials, the current meta-analysis suggests that HME does not decrease VAP incidence or mortality in critically ill patients.

How does temperature affect the function of tissue macrophages?

NASA Astrophysics Data System (ADS)

Lee, Chen-Ting; Repasky, Elizabeth A.

2011-03-01

Macrophages create a major danger signal following injury or infection and upon activation release pro-inflammatory cytokines, which in turn help to generate febrile conditions. Thus, like other cells of the body, tissue macrophages are often exposed to naturally occurring elevations in tissue temperature during inflammation and fever. However, whether macrophages sense and respond to temperature changes in a specific manner which modulates their function is still not clear. In this brief review, we highlight recent studies which have analyzed the effects of temperatures on macrophage function, and summarize the possible underlying molecular mechanisms which have been identified. Mild, physiological range hyperthermia has been shown to have both pro- and anti-inflammatory roles in regulating macrophage inflammatory cytokine production and at the meeting presentation, we will show new data demonstrating that hyperthermia can indeed exert both positive and negative signals to macrophages. While some thermal effects are correlated with the induction of heat shock factors/heat shock proteins, overall it is not clear how mild hyperthermia can exert both pro- and anti-inflammatory functions. We also summarize data which shows that hyperthermia can affect other macrophage effector functions, including the anti-tumor cytotoxicity. Overall, these studies may help us to better understand the immunological role of tissue temperature and may provide important information needed to maximize the application of heat in the treatment of various diseases including cancer.

NCAA Football Off-Season Training: Unanswered Prayers… A Prayer Answered

PubMed Central

Anderson, Scott

2017-01-01

Off-season training in year-round collegiate football is purported to be performance enhancing. Absent principles of exercise physiology, excesses in sport-training regimens pose risk to the participant athletes. Since 2000, 33 National Collegiate Athletic Association (NCAA) football players have died in sport: 27 nontraumatic deaths and 6 traumatic deaths, a ratio of 4.5 nontraumatic deaths for every traumatic death. On average, 2 NCAA football players die per season. Best practices, consensus guidelines, and precautions are ignored, elevating the risk. However, standards exist that will, if heeded, prevent nontraumatic death in athletes training for sport. Sickle cell trait status knowledge and tailored precautions are preventing deaths from exertional collapse associated with sickle cell trait. Adherence to established principles of exercise physiology and best-practice training standards, which is long overdue, will help to prevent not only deaths from exertional collapse associated with sickle cell trait but also sudden cardiac, exertional heat stroke, and asthma deaths. PMID:28140625

The acoustic radiation force on a heated (or cooled) rigid sphere - Theory

NASA Technical Reports Server (NTRS)

Lee, C. P.; Wang, T. G.

1984-01-01

A finite amplitude sound wave can exert a radiation force on an object due to second-order effect of the wave field. The radiation force on a rigid small sphere (i.e., in the long wavelength limit), which has a temperature different from that of the environment, is presently studied. This investigation assumes no thermally induced convection and is relevant to material processing in the absence of gravity. Both isotropic and nonisotropic temperature profiles are considered. In this calculation, the acoustic effect and heat transfer process are essentially decoupled because of the long wavelength limit. The heat transfer information required for determining the force is contained in the parameters, which are integrals over the temperature distribution.

Heat shock protein 60 expression in heart, liver and kidney of broilers exposed to high temperature.

PubMed

Yan, Jianyan; Bao, Endong; Yu, Jimian

2009-06-01

The objective of this study was to investigate the expression and localization of HSP60 in the heart, liver, and kidney of acutely heat-stressed broilers at various stressing times. The plasma creatine kinase (CK) and glutamic pyruvic transaminase (GPT) concentrations statistic increased following heat stress. After 2h of heat stress, the tissues showed histopathological changes. Hsp60 expressed mainly in the cytoplasm of parenchyma cells heat stress. The intensity of the cytoplasmic staining varied and exhibited an organ-specific distribution pattern. Hsp60 levels in the hearts of heat-stressed chickens gradually increased at 1h (p<0.05) and peaked (p<0.05) at 5h; Hsp60 levels in the liver gradually decreased at 3h (p<0.05); Hsp60 levels in the kidney had no fluctuation. It is suggested that Hsp60 expression is tissue-specific and this may be linked to tissue damage in response to heat stress. The Hsp60 level is distinct in diverse tissues, indicating that Hsp60 may exert its protective effect by a tissue- and time-specific mechanism.

An illness-specific version of the Revised Illness Perception Questionnaire in patients with atrial fibrillation (AF IPQ-R): Unpacking beliefs about treatment control, personal control and symptom triggers.

PubMed

Taylor, Elaina C; O'Neill, Mark; Hughes, Lyndsay D; Moss-Morris, Rona

2018-04-01

This study modified the Revised Illness Perception Questionnaire (IPQ-R) in patients with persistent atrial fibrillation (AF). Qualitative interviews and think-aloud techniques informed modification of the IPQ-R to be specific to AF patients. Confirmatory Factor Analysis (CFA) (n = 198) examined the validity of the modified IPQ-R (AF-IPQ-R). Exploratory factor analysis (EFA) examined the new AF-triggers scale. Construct validity examined associations between the AF-IPQ-R, quality of life (QoL) and beliefs about medicines. Test-retest and internal reliability were examined. Interviews indicated that patients viewed triggers of AF rather than initial causes of illness as more applicable. Patients believed specific behaviours such as rest could control AF. Treatment control beliefs related to pharmacological and procedural treatments. These data were used to modify the IPQ-R subscales and to develop a triggers of AF scale. CFA indicated good model fit. EFA of the triggers scale indicated three factors: emotional; health behaviours; and over-exertion triggers. Expected correlations were found between the AF-IPQ-R, QoL and treatment beliefs, evidencing good construct validity. The AF-IPQ-R showed sound psychometric properties. It provides more detailed specification than the IPQ-R of beliefs that may help to understand poor QoL in AF patients, and guidance for future interventions in this area.

Protecting Children from Carbon Monoxide Poisoning

MedlinePlus

... Phases Decontamination Earthquakes Enterovirus D68 Ebola FAQs Extreme Temperatures: Heat and Cold Ebola Financial Crisis Flash Floods ... or hematologic illness (e.g., anemia) that compromise oxygen delivery are more susceptible to adverse effects at ...

Heated hatha yoga to target cortisol reactivity to stress and affective eating in women at risk for obesity-related illnesses: A randomized controlled trial.

PubMed

Hopkins, Lindsey B; Medina, Johnna L; Baird, Scarlett O; Rosenfield, David; Powers, Mark B; Smits, Jasper A J

2016-06-01

Cortisol reactivity to stress is associated with affective eating, an important behavioral risk factor for obesity and related metabolic diseases. Yoga practice is related to decreases in stress and cortisol levels, thus emerging as a potential targeted complementary intervention for affective eating. This randomized controlled trial examined the efficacy of a heated, hatha yoga intervention for reducing cortisol reactivity to stress and affective eating. Females (N = 52; ages 25-46 years; 75% White) at risk for obesity and related illnesses were randomly assigned to 8 weeks of Bikram Yoga practice or to waitlist control. Cortisol reactivity to a laboratory stress induction were measured at Weeks 0 (pretreatment) and 9 (posttreatment). Self-reported binge eating frequency and coping motives for eating were assessed at Weeks 0, 3, 6, and 9. Among participants with elevated cortisol reactivity at pretreatment ("high reactors"), those randomized to the yoga condition evidenced greater pre- to posttreatment reductions in cortisol reactivity (p = .042, d = .85), but there were not significant condition differences for the "low reactors" (p = .178, d = .53). Yoga participants reported greater decreases in binge eating frequency (p = .040, d = .62) and eating to cope with negative affect (p = .038, d = .54). This study provides preliminary support for the efficacy of heated hatha yoga for treating physiological stress reactivity and affective eating among women at risk for obesity-related illnesses. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Internalized stigma and quality of life domains among people with mental illness: the mediating role of self-esteem.

PubMed

Oliveira, Sandra E H; Carvalho, Helena; Esteves, Francisco

2016-01-01

People with mental illness who internalize stigma often experience reduced self-esteem and impaired quality of life (QOL). To propose a theoretical model in which self-esteem mediates the effects of internalized stigma on the multidimensional domains comprising QOL. In 403 inpatients and outpatients (DSM-IV, American Psychiatric Association, 1994), from hospital-based and community mental health facilities, self-report measures of internalized stigma (ISMI), self-esteem (RSES) and QOL (WHOQOL-Bref) were administrated. Structural equation modeling results supported the proposed model. Self-esteem fully mediated the relation between internalized stigma and the physical and the social relationships domains, and partially mediated the relationship between internalized stigma and psychological, environment and level of independence QOL domains. Such results provided empirical support and shed light upon previous research. Specifically the results emphasize the mediating role that self-esteem plays in the degree to which internalized stigma exerts a negative effect on specific QOL domains. Self-esteem appears to be a core element in reducing the negative effects of internalized stigma on aspects of QOL among people with mental illness. These findings suggest there is a crucial impact regarding clinical mental health interventions along with important theoretical implications.

Regional Disparities in Apprentice Attrition Rates: Heat and Quarter Four's Significance in Northern Australia

ERIC Educational Resources Information Center

Zoellner, Don; Brearley, Matt; Oppermann, Elspeth

2017-01-01

Apprenticeship completion rates have remained persistently low for decades in spite of broad agreement over the causes of non-completions. A possible factor missing from these explanations is climate, particularly in northern Australia where traditional trade apprentices are exposed to extreme conditions and exert themselves. We hypothesize that:…

Temporal and spatial variation of heat-related illness using 911 medical dispatch data.

PubMed

Bassil, Kate L; Cole, Donald C; Moineddin, Rahim; Craig, Alan M; Lou, W Y Wendy; Schwartz, Brian; Rea, Elizabeth

2009-07-01

The adverse effect of hot weather on health in urban communities is of increasing public health concern, particularly given trends in climate change. To demonstrate the potential public health applications of monitoring 911 medical dispatch data for heat-related illness (HRI), using historical data for the summer periods (June 1-August 31) during 2002-2005 in Toronto, Ontario, Canada. The temporal distribution of the medical dispatch calls was described in relation to a current early warning system and emergency department data from the National Ambulatory Care Reporting System (NACRS). Geospatial methods were used to map the percentage of heat-related calls in each Toronto neighborhood over the study period. The temporal pattern of 911 calls for HRI was similar, and sometimes peaked earlier, than current heat health warning systems (HHWS). The pattern of calls was similar to NACRS HRI visits, with the exception of 2005 where 911 calls peaked earlier. Areas of the city with a relatively higher burden of HRI included low income inner-city neighborhoods, areas with high rates of street-involved individuals, and areas along the waterfront which include summer outdoor recreational activities. Identifying the temporal trends and geospatial patterns of these important environmental health events has the potential to direct targeted public health interventions to mitigate associated morbidity and mortality.

Singapore Armed Forces Medical Corps-Ministry of Health clinical practice guidelines: management of heat injury.

PubMed

Lee, L; Fock, K M; Lim, C L F; Ong, E H M; Poon, B H; Pwee, K H; O'Muircheartaigh, C R; Seet, B; Tan, C L B; Teoh, C S

2010-10-01

The Singapore Armed Forces (SAF) Medical Corps and the Ministry of Health (MOH) have published clinical practice guidelines on Management of Heat Injury to provide doctors and patients in Singapore with evidence-based guidance on the prevention and clinical management of exertional heat injuries. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the SAF Medical Corps-MOH clinical practice guidelines on Management of Heat Injury, for the information of readers of the Singapore Medical Journal. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: http://www.moh.gov.sg/mohcorp/publications.aspx?id=25178. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

Transient heat stress compromises the resistance of wheat (Poales: Poaceae) seedlings to Hessian fly (Diptera: Cecidomyiidae) infestation.

PubMed

Currie, Yaleaka; Moch, John; Underwood, Joshua; Kharabsheh, Hamzah; Quesenberry, Amy; Miyagi, Risa; Thomas, Carolyn; Boney, Melanie; Woods, Samantha; Chen, Ming-Shun; Zhu, Lieceng

2014-02-01

Heat stress exerts a profound impact on the resistance of plants to parasites. In this research, we investigated the impact of an acute transient heat stress on the resistance of the wheat line 'Molly,' which contains the R gene H13, to an avirulent Hessian fly (Mayetiola destructor (Say)) population. We found that a significant portion of Molly seedlings stressed at 40 degrees C for 6 h during or after the initial Hessian fly larval attack became susceptible to otherwise avirulent insects, whereas unstressed control plants remained 100% resistant. Specifically, 77.8, 73.3, 83.3, and 46.7% of plants heat stressed at 0, 6,12, and 24 h, respectively, after the initial larval attack became susceptible. Biochemical analysis revealed that heat stress caused a transient decrease in 12-oxo-phytodienoic acid, but an increase in salicylic acid accumulation in Molly plants. The change in phytohormones after heat stress and Hessian fly infestation was not observed in 'Newton,' a near-isogenic but Hessian fly susceptible wheat line. Instead, heat stress caused a relatively prolonged reduction in palmitoleic acid. The role of phytohormones in heat-induced loss of wheat resistance was discussed.

Manual materials handling: the cause of over-exertion injury and illness in industry.

PubMed

Chaffin, D B

1979-01-01

It is reported from various sources that overexertion due to lifting, pushing, pulling, and carrying objects accounts for about 27 percent of all compensable industrial injury and illness in the United States. Resulting strain/sprain injuries account for over 50 percent of workmen's compensation clams in many industries. Almont two-thirds of these involve back pain, with reported compensation and medical payments totaling well over one billion dollars annually in the U.S. An estimated 300,000 plus workers will be affected each year, 5 to 10 percent of whom will have a permanent disability and often will be unemployable. This paper attempts to describe four basic approaches used to study this occupational health problem. In so doing, a concerted effort is made to identifiy the gaps in knowledge which need to be more fully researched. The approaches utilized to understand and control the hazards of manual materials handling are: 1) epidemiological studies of job and worker attributes to identify those that individually and in combination cause musculoskeletal incidents, 2) psychophysical studies to ascertain the volitional tolerance of workers to the stress mitigated by manual materials-handling activities, 3) biomechanical studies of the musculoskeletal system during common exertions required in manual materials-handling activities, and 4) physiological studies of the strain imposed on the cardiovascular system during repeated load-handling activities. The state of knowledge from each of these approaches is summarized briefly, and a case is made that much research is still needed to substantiate the necessary controls to lessen the economic burden and human suffering associated with manual materials-handling acts in industry.

Climate Change and the Emergent Epidemic of CKD from Heat Stress in Rural Communities: The Case for Heat Stress Nephropathy.

PubMed

Glaser, Jason; Lemery, Jay; Rajagopalan, Balaji; Diaz, Henry F; García-Trabanino, Ramón; Taduri, Gangadhar; Madero, Magdalena; Amarasinghe, Mala; Abraham, Georgi; Anutrakulchai, Sirirat; Jha, Vivekanand; Stenvinkel, Peter; Roncal-Jimenez, Carlos; Lanaspa, Miguel A; Correa-Rotter, Ricardo; Sheikh-Hamad, David; Burdmann, Emmanuel A; Andres-Hernando, Ana; Milagres, Tamara; Weiss, Ilana; Kanbay, Mehmet; Wesseling, Catharina; Sánchez-Lozada, Laura Gabriela; Johnson, Richard J

2016-08-08

Climate change has led to significant rise of 0.8°C-0.9°C in global mean temperature over the last century and has been linked with significant increases in the frequency and severity of heat waves (extreme heat events). Climate change has also been increasingly connected to detrimental human health. One of the consequences of climate-related extreme heat exposure is dehydration and volume loss, leading to acute mortality from exacerbations of pre-existing chronic disease, as well as from outright heat exhaustion and heat stroke. Recent studies have also shown that recurrent heat exposure with physical exertion and inadequate hydration can lead to CKD that is distinct from that caused by diabetes, hypertension, or GN. Epidemics of CKD consistent with heat stress nephropathy are now occurring across the world. Here, we describe this disease, discuss the locations where it appears to be manifesting, link it with increasing temperatures, and discuss ongoing attempts to prevent the disease. Heat stress nephropathy may represent one of the first epidemics due to global warming. Government, industry, and health policy makers in the impacted regions should place greater emphasis on occupational and community interventions. Copyright © 2016 by the American Society of Nephrology.

Pathophysiology of Heat-Related Illnesses

DTIC Science & Technology

2012-01-01

Figure 10-4). deHydrATion And elecTrolyTe imBAlAnce Water requirements during heat exposure are primarily deter- mined by a person’s sweat losses. Water...the effect of cyclooxygenase inhibition, J Clin Invest 81:1162, 1988. 241. Opal SM, Fisher CJ Jr, Dhainaut JF, et al: Confirmatory interleukin-1...inhibition, J Clin Invest 81:1162, 1988. 241. Opal SM, Fisher CJ Jr, Dhainaut JF, et al: Confirmatory interleukin-1 receptor antagonist trial in severe

Substitutions of cysteine residues of Escherichia coli heat-stable enterotoxin by oligonucleotide-directed mutagenesis.

PubMed Central

Okamoto, K; Okamoto, K; Yukitake, J; Kawamoto, Y; Miyama, A

1987-01-01

The Escherichia coli 18-amino-acid, heat-stable enterotoxin STp has six cysteine residues linked intramolecularly by three disulfide bonds. These disulfide bonds are important for toxic activity, but the precise role of each bond is not clear. We substituted cysteine residues of STp in vivo by oligonucleotide-directed site-specific mutagenesis to dissociate each disulfide bond and examined the biological activities of the resulting mutants. The Cys-6----Ala and Cys-17----Ala mutations caused a complete loss of toxic activity. The Cys-5----Ala, Cys-10----Ser, and Gly-16, Cys-17----Cys-16, Gly-17 mutations caused a large decrease in toxic activity. These results mean that all three disulfide bonds formed at fixed positions are required for full expression of the biological activity of STp. However, a weak but significant toxicity still remained after three mutations, Cys-5----Ala, Cys-10----Ser, and Gly-16, Cys-17----Cys-16, Gly-17. This indicates that STp has some flexibilities in its conformation to exert toxic activity and that the role of each disulfide bond exerting toxic activity is not quite the same. Images PMID:3305364

Personal, closed-cycle cooling and protective apparatus and thermal battery therefor

DOEpatents

Klett, James W.; Klett, Lynn B.

2004-07-20

A closed-cycle apparatus for cooling a living body includes a heat pickup body or garment which permits evaporation of an evaporating fluid, transmission of the vapor to a condenser, and return of the condensate to the heat pickup body. A thermal battery cooling source is provided for removing heat from the condenser. The apparatus requires no external power and provides a cooling system for soldiers, race car drivers, police officers, firefighters, bomb squad technicians, and other personnel who may utilize protective clothing to work in hostile environments. An additional shield layer may simultaneously provide protection from discomfort, illness or injury due to harmful atmospheres, projectiles, edged weapons, impacts, explosions, heat, poisons, microbes, corrosive agents, or radiation, while simultaneously removing body heat from the wearer.

Cold and Heat Stress Diversely Alter Both Cauliflower Respiration and Distinct Mitochondrial Proteins Including OXPHOS Components and Matrix Enzymes

PubMed Central

Rurek, Michał; Czołpińska, Magdalena; Pawłowski, Tomasz Andrzej; Krzesiński, Włodzimierz; Spiżewski, Tomasz

2018-01-01

Complex proteomic and physiological approaches for studying cold and heat stress responses in plant mitochondria are still limited. Variations in the mitochondrial proteome of cauliflower (Brassica oleracea var. botrytis) curds after cold and heat and after stress recovery were assayed by two-dimensional polyacrylamide gel electrophoresis (2D PAGE) in relation to mRNA abundance and respiratory parameters. Quantitative analysis of the mitochondrial proteome revealed numerous stress-affected protein spots. In cold, major downregulations in the level of photorespiratory enzymes, porine isoforms, oxidative phosphorylation (OXPHOS) and some low-abundant proteins were observed. In contrast, carbohydrate metabolism enzymes, heat-shock proteins, translation, protein import, and OXPHOS components were involved in heat response and recovery. Several transcriptomic and metabolic regulation mechanisms are also suggested. Cauliflower plants appeared less susceptible to heat; closed stomata in heat stress resulted in moderate photosynthetic, but only minor respiratory impairments, however, photosystem II performance was unaffected. Decreased photorespiration corresponded with proteomic alterations in cold. Our results show that cold and heat stress not only operate in diverse modes (exemplified by cold-specific accumulation of some heat shock proteins), but exert some associations at molecular and physiological levels. This implies a more complex model of action of investigated stresses on plant mitochondria. PMID:29547512

Calcium promotes activity and confers heat stability on plant peroxidases

PubMed Central

Plieth, Christoph; Vollbehr, Sonja

2012-01-01

In this paper we demonstrate how peroxidase (PO) activities and their heat stability correlate with the availability of free Ca2+ ions. Calcium ions work as a molecular switch for PO activity and exert a protective function, rendering POs heat stable. The concentration ranges of these two activities differ markedly. POs are activated by µM Ca2+ concentration ranges, whereas heat stabilization is observed in the nM range. This suggests the existence of different Ca2+ binding sites. The heat stability of POs depends on the source plant species. Terrestrial plants have POs that exhibit higher temperature stability than those POs from limnic and marine plants. Different POs from a single species can differ in terms of heat stability. The abundance of different POs within a plant is dependent on age and developmental stage. The heat stability of a PO does not necessarily correlate with the maximum temperature the source species is usually exposed to in its natural habitat. This raises questions on the role of POs in the heat tolerance of plants. Consequently, detailed investigations are needed to identify and characterize individual POs, with regard to their genetic origin, subcellular expression, tissue abundance, developmental emergence and their functions in innate and acquired heat tolerance. PMID:22580695

Health symptoms in relation to temperature, humidity, and self-reported perceptions of climate in New York City residential environments

NASA Astrophysics Data System (ADS)

Quinn, Ashlinn; Shaman, Jeffrey

2017-07-01

Little monitoring has been conducted of temperature and humidity inside homes despite the fact that these conditions may be relevant to health outcomes. Previous studies have observed associations between self-reported perceptions of the indoor environment and health. Here, we investigate associations between measured temperature and humidity, perceptions of indoor environmental conditions, and health symptoms in a sample of New York City apartments. We measured temperature and humidity in 40 New York City apartments during summer and winter seasons and collected survey data from the households' residents. Health outcomes of interest were (1) sleep quality, (2) symptoms of heat illness (summer season), and (3) symptoms of respiratory viral infection (winter season). Using mixed-effects logistic regression models, we investigated associations between the perceptions, symptoms, and measured conditions in each season. Perceptions of indoor temperature were significantly associated with measured temperature in both the summer and the winter, with a stronger association in the summer season. Sleep quality was inversely related to measured and perceived indoor temperature in the summer season only. Heat illness symptoms were associated with perceived, but not measured, temperature in the summer season. We did not find an association between any measured or perceived condition and cases of respiratory infection in the winter season. Although limited in size, the results of this study reveal that indoor temperature may impact sleep quality, and that thermal perceptions of the indoor environment may indicate vulnerability to heat illness. These are both important avenues for further investigation.

A novel early risk assessment tool for detecting clinical outcomes in patients with heat-related illness (J-ERATO score): Development and validation in independent cohorts in Japan.

PubMed

Hayashida, Kei; Kondo, Yutaka; Hifumi, Toru; Shimazaki, Junya; Oda, Yasutaka; Shiraishi, Shinichiro; Fukuda, Tatsuma; Sasaki, Junichi; Shimizu, Keiki

2018-01-01

We sought to develop a novel risk assessment tool to predict the clinical outcomes after heat-related illness. Prospective, multicenter observational study. Patients who transferred to emergency hospitals in Japan with heat-related illness were registered. The sample was divided into two parts: 60% to construct the score and 40% to validate it. A binary logistic regression model was used to predict hospital admission as a primary outcome. The resulting model was transformed into a scoring system. A total of 3,001 eligible patients were analyzed. There was no difference in variables between development and validation cohorts. Based on the result of a logistic regression model in the development phase (n = 1,805), the J-ERATO score was defined as the sum of the six binary components in the prehospital setting (respiratory rate≥22 /min, Glasgow coma scale<15, systolic blood pressure≤100 mmHg, heart rate≥100 bpm, body temperature≥38°C, and age≥65 y), for a total score ranging from 0 to 6. In the validation phase (n = 1,196), the score had excellent discrimination (C-statistic 0.84; 95% CI 0.79-0.89, p<0.0001) and calibration (P>0.2 by Hosmer-Lemeshow test). The observed proportion of hospital admission increased with increasing J-ERATO score (score = 0, 5.0%; score = 1, 15.0%; score = 2, 24.6%; score = 3, 38.6%; score = 4, 68.0%; score = 5, 85.2%; score = 6, 96.4%). Multivariate analyses showed that the J-ERATO score was an independent positive predictor of hospital admission (adjusted OR, 2.43; 95% CI, 2.06-2.87; P<0.001), intensive care unit (ICU) admission (3.73; 2.95-4.72; P<0.001) and in-hospital mortality (1.65; 1.18-2.32; P = 0.004). The J-ERATO score is simply assessed and can facilitate the identification of patients with higher risk of heat-related hospitalization. This scoring system is also significantly associated with the higher likelihood of ICU admission and in-hospital mortality after heat-related hospitalization.

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms

PubMed Central

Twisk, Frank NM

2015-01-01

Although myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) are considered to be synonymous, the definitional criteria for ME and CFS define two distinct, partially overlapping, clinical entities. ME, whether defined by the original criteria or by the recently proposed criteria, is not equivalent to CFS, let alone a severe variant of incapacitating chronic fatigue. Distinctive features of ME are: muscle weakness and easy muscle fatigability, cognitive impairment, circulatory deficits, a marked variability of the symptoms in presence and severity, but above all, post-exertional “malaise”: a (delayed) prolonged aggravation of symptoms after a minor exertion. In contrast, CFS is primarily defined by (unexplained) chronic fatigue, which should be accompanied by four out of a list of 8 symptoms, e.g., headaches. Due to the subjective nature of several symptoms of ME and CFS, researchers and clinicians have questioned the physiological origin of these symptoms and qualified ME and CFS as functional somatic syndromes. However, various characteristic symptoms, e.g., post-exertional “malaise” and muscle weakness, can be assessed objectively using well-accepted methods, e.g., cardiopulmonary exercise tests and cognitive tests. The objective measures acquired by these methods should be used to accurately diagnose patients, to evaluate the severity and impact of the illness objectively and to assess the positive and negative effects of proposed therapies impartially. PMID:26140274

Heat and moisture exchangers (HMEs) and heated humidifiers (HHs) in adult critically ill patients: a systematic review, meta-analysis and meta-regression of randomized controlled trials.

PubMed

Vargas, Maria; Chiumello, Davide; Sutherasan, Yuda; Ball, Lorenzo; Esquinas, Antonio M; Pelosi, Paolo; Servillo, Giuseppe

2017-05-29

The aims of this systematic review and meta-analysis of randomized controlled trials are to evaluate the effects of active heated humidifiers (HHs) and moisture exchangers (HMEs) in preventing artificial airway occlusion and pneumonia, and on mortality in adult critically ill patients. In addition, we planned to perform a meta-regression analysis to evaluate the relationship between the incidence of artificial airway occlusion, pneumonia and mortality and clinical features of adult critically ill patients. Computerized databases were searched for randomized controlled trials (RCTs) comparing HHs and HMEs and reporting artificial airway occlusion, pneumonia and mortality as predefined outcomes. Relative risk (RR), 95% confidence interval for each outcome and I 2 were estimated for each outcome. Furthermore, weighted random-effect meta-regression analysis was performed to test the relationship between the effect size on each considered outcome and covariates. Eighteen RCTs and 2442 adult critically ill patients were included in the analysis. The incidence of artificial airway occlusion (RR = 1.853; 95% CI 0.792-4.338), pneumonia (RR = 932; 95% CI 0.730-1.190) and mortality (RR = 1.023; 95% CI 0.878-1.192) were not different in patients treated with HMEs and HHs. However, in the subgroup analyses the incidence of airway occlusion was higher in HMEs compared with HHs with non-heated wire (RR = 3.776; 95% CI 1.560-9.143). According to the meta-regression, the effect size in the treatment group on artificial airway occlusion was influenced by the percentage of patients with pneumonia (β = -0.058; p = 0.027; favors HMEs in studies with high prevalence of pneumonia), and a trend was observed for an effect of the duration of mechanical ventilation (MV) (β = -0.108; p = 0.054; favors HMEs in studies with longer MV time). In this meta-analysis we found no superiority of HMEs and HHs, in terms of artificial airway occlusion, pneumonia and mortality. A trend favoring HMEs was observed in studies including a high percentage of patients with pneumonia diagnosis at admission and those with prolonged MV. However, the choice of humidifiers should be made according to the clinical context, trying to avoid possible complications and reaching the appropriate performance at lower costs.

Production Methodology for the Validation of Electronic Fuzes

DTIC Science & Technology

1980-11-01

are employed age cantridge o; magazine This mud’e is shown in figure Vtll-t (f) Fxtensis’e debuggngij and troubleshooting to perfect the automatic...All the plastic manterials platens The heat is supplied bs steam, heated can be fabricated b% more than one methoid , al- liquids, electrical res.stance...on-I-ne data bases, or the real-time data acquisition Resources %%ill be performizble- Thus. tbe adsantages that cook ;i be realized by full use of

Method of fabricating an article with cavities. [with thin bottom walls

NASA Technical Reports Server (NTRS)

Dale, W. J.; Jurscaga, G. M. (Inventor)

1974-01-01

An article having a cavity with a thin bottom wall is provided by assembling a thin sheet, for example, a metal sheet, adjacent to the surface of a member having one or more apertures. A bonding adhesive is interposed between the thin sheet and the subadjacent member, and the thin sheet is subjected to a high fluid pressure. In order to prevent the differential pressure from being exerted against the thin sheet, the aperture is filled with a plug of solid material having a linear coefficient of thermal expansion higher than that of the member. When the assembly is subjected to pressure, the material is heated to a temperature such that its expansion exerts a pressure against the thin sheet thus reducing the differential pressure.

Novel psychoactive substances (NPS) use in severe mental illness (SMI) patients: Potential changes in the phenomenology of psychiatric diseases.

PubMed

Bersani, Giuseppe; Prevete, Elisabeth

2017-05-01

Literature is quite poor about the clinical effects of novel psychoactive substances (NPS) and the long-term consequences of NPS use in psychiatric patients. Consequently, it is of the greatest interest to examine which effects NPS can exert in patients with previous severe mental illness (SMI), such as psychotic patients. The aim of this work was a comprehensive review about NPS use in patients with SMI. We searched Medline or PubMed for relevant English-language citations and reviews describing relationships between NPS use and mental disorders, as well as for the main groups of substances and associated psychiatric manifestations. All studies reporting single case or case series of patients were selected. The NPS use in patients with SMI is probably underestimated. The one existing systematic review considers only 14 studies, 12 of which are case reports. Most clinical results report acute symptom exacerbation of preexisting psychosis. Paranoid, mood, and aggression symptoms occur more frequently. NPS use could modify clinical features of SMI, but these conclusions cannot be generalizable. More evidence is needed to establish the causal and effective connection between NPS use and course of illness, type of psychiatric symptoms, and outcome of treatment in terms of adherence or response. Copyright © 2017 John Wiley & Sons, Ltd.

Preventing Giardia Infection.

ERIC Educational Resources Information Center

Beer, W. Nicholas

1993-01-01

Outdoor recreationists are at risk for developing giardia infection from drinking contaminated stream water. Giardia is the most common human parasite found in contaminated water that causes gastrointestinal illness. Describes medical treatment and ways of preventing infection through water treatment, including heat, filtration, and chemical…

The effect of prolonged light intensity exercise in the heat on executive function.

PubMed

Parker, Sarah M; Erin, Jennifer R; Pryor, Riana R; Khorana, Priya; Suyama, Joe; Guyette, Frank X; Reis, Steven E; Hostler, David

2013-09-01

When people are involved in outdoor activities, it is important to be able to assess a situation and make rational decisions. The goal of this study is to determine the effects of 90 minutes of light-intensity exercise in a hot environment on executive functioning capabilities of healthy individuals. In this prospective laboratory study, 40 healthy male and female subjects 18 to 45 years of age performed treadmill exercise while wearing athletic clothing and a backpack in either a hot or temperate environment. Vital signs, core and skin temperature, and perceptual measures (thermal sensation, sweating, comfort, and perceived exertion) were measured before, during, and after the treadmill test. Cognitive function was measured before and after the treadmill test using the Wisconsin Card Sorting Test (WCST) and a Psychomotor Vigilance Test (PVT). Subjects in the hot condition reached a similar core temp of 38.2° ± 0.5°C vs 37.7° ± 0.3°C (P = .325) in the temperate group but had a higher heart rate (P < .001) and skin temperature (P < .001). Hot and normal temperature groups did not differ in their PVT performance. There were more correct responses (P < .001), fewer errors (P < .001), and more conceptual responses (P = .001) on the WCST after exertion in both the hot room and normal temperature room conditions. Perseverations and perseverative errors (P = .002) decreased in both groups after exertion. Conditions of mild heat stress coupled with modest rehydration and short hiking treks do not appear to negatively affect executive function or vigilance. Copyright © 2013 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Ambient temperature and added heat wave effects on hospitalizations in California from 1999 to 2009.

PubMed

Sherbakov, Toki; Malig, Brian; Guirguis, Kristen; Gershunov, Alexander; Basu, Rupa

2018-01-01

Investigators have examined how heat waves or incremental changes in temperature affect health outcomes, but few have examined both simultaneously. We utilized distributed lag nonlinear models (DLNM) to explore temperature associations and evaluate possible added heat wave effects on hospitalizations in 16 climate zones throughout California from May through October 1999-2009. We define heat waves as a period when daily mean temperatures were above the zone- and month-specific 95th percentile for at least two consecutive days. DLNMs were used to estimate climate zone-specific non-linear temperature and heat wave effects, which were then combined using random effects meta-analysis to produce an overall estimate for each. With higher temperatures, admissions for acute renal failure, appendicitis, dehydration, ischemic stroke, mental health, non-infectious enteritis, and primary diabetes were significantly increased, with added effects from heat waves observed for acute renal failure and dehydration. Higher temperatures also predicted statistically significant decreases in hypertension admissions, respiratory admissions, and respiratory diseases with secondary diagnoses of diabetes, though heat waves independently predicted an added increase in risk for both respiratory types. Our findings provide evidence that both heat wave and temperature exposures can exert effects independently. Copyright © 2017 Elsevier Inc. All rights reserved.

Study of the influence of sporulation conditions on heat resistance of Geobacillus stearothermophilus used in the development of biological indicators for steam sterilization.

PubMed

Guizelini, Belquis P; Vandenberghe, Luciana P S; Sella, Sandra Regina B R; Soccol, Carlos Ricardo

2012-12-01

Biological indicators are important tools in infection control via sterilization process monitoring. The use of a standardized spore crop with a well-defined heat resistance will guarantee the quality of a biological indicator. Ambient factors during sporulation can affect spore characteristics and properties, including heat resistance. The aim of this study is to evaluate the main sporulation factors responsible for heat resistance in Geobacillus stearothermophilus, a useful biological indicator for steam sterilization. A sequence of a three-step optimization of variables (initial pH, nutrient concentration, tryptone, peptone, beef extract, yeast extract, manganese sulfate, magnesium sulfate, calcium chloride and potassium phosphate) was carried out to screen those that have a significant influence on heat resistance of produced spores. The variable exerting greatest influence on G. stearothermophilus heat resistance during sporulation was found to be the initial pH. Lower nutrient concentration and alkaline pH around 8.5 tended to enhance decimal reduction time at 121 °C (D(121°C)). A central composite design enabled a fourfold enhancement in heat resistance, and the model obtained accurately describes positive pH and negative manganese sulfate concentration influence on spore heat resistance.

Joule heating effects on particle immobilization in insulator-based dielectrophoretic devices

PubMed Central

Gallo-Villanueva, Roberto C.; Sano, Michael B.; Lapizco-Encinas, Blanca H.; Davalos, Rafael V.

2014-01-01

In this work, the temperature effects due to Joule heating obtained by application of a DC electric potential were investigated for a microchannel with cylindrical insulating posts employed for insulator based dielectrophoresis (iDEP). The conductivity of the suspending medium, the local electric field, and the gradient of the squared electric field, which directly affect the magnitude of the dielectrophoretic force exerted on particles, were computationally simulated employing COMSOL Multiphysics. It was observed that a temperature gradient is formed along the microchannel which redistributes the conductivity of the suspending medium leading to an increase of the dielectrophoretic force towards the inlet of the channel while decreasing towards the outlet. Experimental results are in good agreement with simulations on the particle trapping zones anticipated. This study demonstrates the importance of considering Joule heating effects when designing iDEP systems. PMID:24002905

Enterotoxigenic Escherichia coli blood group A interactions intensify diarrheal severity.

PubMed

Kumar, Pardeep; Kuhlmann, F Matthew; Chakroborty, Subhra; Bourgeois, A Louis; Foulke-Abel, Jennifer; Tumala, Brunda; Vickers, Tim J; Sack, David A; DeNearing, Barbara; Harro, Clayton D; Wright, W Shea; Gildersleeve, Jeffrey C; Ciorba, Matthew A; Santhanam, Srikanth; Porter, Chad K; Gutierrez, Ramiro L; Prouty, Michael G; Riddle, Mark S; Polino, Alexander; Sheikh, Alaullah; Donowitz, Mark; Fleckenstein, James M

2018-05-17

Enterotoxigenic Escherichia coli (ETEC) infections are highly prevalent in developing countries where clinical presentations range from asymptomatic colonization to severe cholera-like illness. The molecular basis for these varied presentations, that may involve strain-specific virulence features as well as host factors, have not been elucidated. We demonstrate that when challenged with ETEC strain H10407, originally isolated from a case of cholera-like illness, blood group A human volunteers developed severe diarrhea more frequently than individuals from other blood groups. Interestingly, a diverse population of ETEC strains, including H10407, secrete a novel adhesin molecule, EtpA. As many bacterial adhesins also agglutinate red blood cells, we combined the use of glycan arrays, biolayer inferometry, and non-canonical amino acid labeling with hemagglutination studies to demonstrate that EtpA is a dominant ETEC blood group A specific lectin/hemagglutinin. Importantly, we also show that EtpA interacts specifically with glycans expressed on intestinal epithelial cells from blood group A individuals, and that EtpA-mediated bacterial-host interactions accelerate bacterial adhesion and the effective delivery both heat-labile and heat-stable toxins of ETEC. Collectively, these data provide additional insight into the complex molecular basis of severe ETEC diarrheal illness that may inform rational design of vaccines to protect those at highest risk.

Development of a surveillance case definition for heat-related illness using 911 medical dispatch data.

PubMed

Bassil, Kate L; Cole, Donald C; Moineddin, Rahim; Gournis, Effie; Schwartz, Brian; Craig, Alan M; Lou, W Y Wendy; Rea, Elizabeth

2008-01-01

The adverse effects of hot weather on public health are of increasing concern. A surveillance system using 911 medical dispatch data for the detection of heat-related illness (HRI) could provide new information on the impact of excessive heat on the population. This paper describes how we identified medical dispatch call codes, called "determinants", that could represent HRI events. Approximately 500 medical dispatch determinants were reviewed in focus groups composed of Emergency Medical Services (EMS) paramedics, dispatchers, physicians, and public health epidemiologists. Each group was asked to select those determinants that might adequately represent HRI. Selections were then assessed empirically using correlations with daily mean temperature over the study period (June 1-August 31,2005). The focus groups identified 12 determinant groupings and ranked them according to specificity for HRI. Of these, "Heat/cold exposure" was deemed the most specific. The call determinant groupings with the clearest positive associations with daily mean temperature empirically were "Heat/cold exposure" (Spearman's correlation coefficient (SCC) 0.71, p < 0.0001) and "Unknown problem (man down)" (SCC 0.21, p = 0.04). Within each grouping, the determinant "Unknown status (3rd party caller)" showed significant associations, SCC = 0.34 (p = 0.001) and SCC = 0.22 (p = 0.03) respectively. Clinically-informed expertise and empirical evidence both contributed to identification of a group of 911 medical dispatch call determinants that plausibly represent HRI events. Once evaluated prospectively, these may be used in public health surveillance to better understand environmental health impacts on human populations and inform targeted public health interventions.

Elevated interictal serum HSP-70 levels as an indicator of neurodegeneration for chronic migraine.

PubMed

Yon, Mehmet Ilker; Titiz, Ayse Pinar; Bilen, Sule; Ulusoy, Ersin Kasim; Gulunay, Aydin; Karakoc, Mehmet; Yon, Merve Ecem Erdogan; Ak, Fikri

2016-06-01

To investigate whether there is a relationship between chronic migraine and heat shock protein-70. The case-control progressive study was conducted at Ankara Numune Teaching and Research Hospital, Ankara, Turkey, from January to June 2013, and comprised patients over 18 years of age who were diagnosed with chronic migraine and did not have any other known neurological illness. Age and gender-matched volunteers with no history of headache or neurological illness were included as controls. In order to exclude other central nervous system diseases, computed tomography and/or magnetic resonance imaging was carried out. Blood samples to evaluate serum heat shock protein-70 levels were obtained from the patients during headache-free periods and from the controls following 8 hours of fasting. The samples were interpreted using the enzyme-linked immunosorbent assay reader. There were 40 controls and an equal number of cases in the study. Mean heat shock protein-70 levels were higher in the cases 2.37±1.91ng/dl compared to thecontrols1.81±1.30 ng/dl, but the difference was not statistically significant (p=0.12). Serum heat shock protein-70 levels were also compared in terms of the duration of migraine disease, frequency of migraine attacks, Visual Analogue Scale score, migraine attack duration and the presence of aura, but no statistically significant difference was found (p=0.13, p=0.17, p=0.90, p=0.68, p=0.95 respectively). Heat shock protein-70 was not a reliable chronic migraine biomarker.

INFECTIOUS MYXOMATOSIS OF RABBITS

PubMed Central

Smadel, Joseph E.; Ward, S. M.; Rivers, Thomas M.

1940-01-01

A second soluble antigen, separable from the virus, occurs in extracts of infected skin and in the serum of rabbits acutely ill with infectious myxomatosis. Like the first antigen (A), the second (B) is heat labile and has certain characteristics of a globulin. The two antigens precipitate in different concentrations of ammonium sulfate and can be separated by this method. Neither of the antigens after being heated at 56°C. precipitates in the presence of specific antibody but each is capable of inhibiting the activity of its antibody. PMID:19871012

Regulation of thermogenesis in plants: the interaction of alternative oxidase and plant uncoupling mitochondrial protein.

PubMed

Zhu, Yan; Lu, Jianfei; Wang, Jing; Chen, Fu; Leng, Feifan; Li, Hongyu

2011-01-01

Thermogenesis is a process of heat production in living organisms. It is rare in plants, but it does occur in some species of angiosperm. The heat is generated via plant mitochondrial respiration. As possible involvement in thermogenesis of mitochondrial factors, alternative oxidases (AOXs) and plant uncoupling mitochondrial proteins (PUMPs) have been well studied. AOXs and PUMPs are ubiquitously present in the inner membrane of plant mitochondria. They serve as two major energy dissipation systems that balance mitochondrial respiration and uncoupled phosphorylation by dissipating the H+ redox energy and proton electrochemical gradient (ΔμH+) as heat, respectively. AOXs and PUMPs exert similar physiological functions during homeothermic heat production in thermogenic plants. AOXs have five isoforms, while PUMPs have six. Both AOXs and PUMPs are encoded by small nuclear multigene families. Multiple isoforms are expressed in different tissues or organs. Extensive studies have been done in the area of thermogenesis in higher plants. In this review, we focus on the involvement and regulation of AOXs and PUMPs in thermogenesis.

Continuous fiber thermoplastic prepreg

NASA Technical Reports Server (NTRS)

Wilson, Maywood L. (Inventor); Johnson, Gary S. (Inventor)

1993-01-01

A pultrusion machine employing a corrugated impregnator vessel to immerse multiple, continuous strand, fiber tow in an impregnating material, and an adjustable metered exit orifice for the impregnator vessel to control the quantity of impregnating material retained by the impregnated fibers, is provided. An adjustable height insert retains transverse rod elements within each depression of the corrugated vessel to maintain the individual fiber tows spread and in contact with the vessel bottom. A series of elongated heating dies, transversely disposed on the pultrusion machine and having flat heating surfaces with radiused edges, ensure adequate temperature exposed dwell time and exert adequate pressure on the impregnated fiber tows, to provide the desired thickness and fiber/resin ratio in the prepreg formed. The prepreg passing through the pulling mechanism is wound on a suitable take-up spool for subsequent use. A formula is derived for determining the cross sectional area opening of the metering device. A modification in the heating die system employs a heated nip roller in lieu of one of the pressure applying flat dies.

ANALYZING DRINKING WATER FOR DISINFECTION BYPRODUCTS

EPA Science Inventory

In the mid 19th Century, Chinese workers on the North American transcontinental railroad suffered less illness than other groups. While generally mysterious at the time, today the reason is obvious. The Chinese preference for tea required heating the water, thus killing many path...

Decoupled Method for Reconstruction of Surface Conditions From Internal Temperatures On Ablative Materials With Uncertain Recession Model

NASA Technical Reports Server (NTRS)

Oliver, A. Brandon

2017-01-01

Obtaining measurements of flight environments on ablative heat shields is both critical for spacecraft development and extremely challenging due to the harsh heating environment and surface recession. Thermocouples installed several millimeters below the surface are commonly used to measure the heat shield temperature response, but an ill-posed inverse heat conduction problem must be solved to reconstruct the surface heating environment from these measurements. Ablation can contribute substantially to the measurement response making solutions to the inverse problem strongly dependent on the recession model, which is often poorly characterized. To enable efficient surface reconstruction for recession model sensitivity analysis, a method for decoupling the surface recession evaluation from the inverse heat conduction problem is presented. The decoupled method is shown to provide reconstructions of equivalent accuracy to the traditional coupled method but with substantially reduced computational effort. These methods are applied to reconstruct the environments on the Mars Science Laboratory heat shield using diffusion limit and kinetically limited recession models.

A project for exploitation of a new form of solar energy: the wind chill. I - The importance to the energy field. II - Application for building heat and electricity production

NASA Astrophysics Data System (ADS)

Le Goff, P.

Calculations of the temperature, humidity, pressure, and velocity of the wind at different locations are provided to demonstrate that energy characteristics of the wind other than the mechanical pressure exerted by the wind on obstacles are significant. A system is described, based on the heat pump principle, which takes advantage of the thermal inertia of the wind, known to remain around freezing even in Siberian winters. An analysis of the energy available for heat transfer in a site in France demonstrates that the dryness, warmth, or chill of a cubic meter of air contains, continuously, 100-1000 times the kinetic energy of moving air. In excess of one kilowatt/sq m is available for extraction by heat pumps based on designs for ocean thermal energy conversion. An electric generating system is described which would yield 10-50 times the mechanical power of a windmill using the same collector area. Finally, a wall heat exchanger for a house is presented which would gain heat energy proportional to the severity of the winter wind.

Heat resistance of histamine-producing bacteria in irradiated tuna loins.

PubMed

Enache, Elena; Kataoka, Ai; Black, D Glenn; Weddig, Lisa; Hayman, Melinda; Bjornsdottir-Butler, Kristin

2013-09-01

Consumption of foods high in biogenic amines leads to an illness known as histamine, or scombrotoxin, poisoning. The illness is commonly associated with consumption of fish with high levels of histamine ( $ 500 ppm). The objective of this study was to determine and compare the heat resistance of five histamine-producing bacteria in irradiated albacore tuna loins. Heat-resistance parameters (D- and z-values) were determined for Morganella morganii, Raoultella planticola, Hafnia alvei, and Enterobacter aerogenes. D- or z-values were not determined for Photobacterium damselae, which was the most heat-sensitive organism in this study. P. damselae declined > 5.9 log CFU/g after a heat treatment of 50°C for 10 min, 54°C for 3 min, and 56°C for 0.5 min. M. morganii was the most heat-resistant histamine-producing bacteria in albacore tuna loins, followed by E. aerogenes, H. alvei, and R. planticola. M. morganii and E. aerogenes had the highest D(50°C), 49.7 ± 17.57 and 51.8 ± 17.38 min, respectively. In addition, M. morganii had the highest D-values for all other temperatures (54, 56, and 58°C) tested. D- and zvalues were also determined for M. morganii in skipjack tuna. While no significant (P > 0.05) difference was observed between D(54°C) and D(56°C) of M. morganii in either albacore or skipjack tuna, the D(58°C) (0.4 ± 0.17 min) was significantly lower (P < 0.05) in skipjack than in albacore (0.9 ± 0.24 min). The z-values for all organisms tested were in the range of 3.2 to 3.8°C. This study suggests that heat treatment designed to control M. morganii in tuna loins is sufficient for controlling histamine-producing bacteria in canned-tuna processing environments.

Regolith thermal property inversion in the LUNAR-A heat-flow experiment

NASA Astrophysics Data System (ADS)

Hagermann, A.; Tanaka, S.; Yoshida, S.; Fujimura, A.; Mizutani, H.

2001-11-01

In 2003, two penetrators of the LUNAR--A mission of ISAS will investigate the internal structure of the Moon by conducting seismic and heat--flow experiments. Heat-flow is the product of thermal gradient tial T / tial z, and thermal conductivity λ of the lunar regolith. For measuring the thermal conductivity (or dissusivity), each penetrator will carry five thermal property sensors, consisting of small disc heaters. The thermal response Ts(t) of the heater itself to the constant known power supply of approx. 50 mW serves as the data for the subsequent data interpretation. Horai et al. (1991) found a forward analytical solution to the problem of determining the thermal inertia λ ρ c of the regolith for constant thermal properties and a simplyfied geometry. In the inversion, the problem of deriving the unknown thermal properties of a medium from known heat sources and temperatures is an Identification Heat Conduction Problem (IDHCP), an ill--posed inverse problem. Assuming that thermal conductivity λ and heat capacity ρ c are linear functions of temperature (which is reasonable in most cases), one can apply a Kirchhoff transformation to linearize the heat conduction equation, which minimizes computing time. Then the error functional, i.e. the difference between the measured temperature response of the heater and the predicted temperature response, can be minimized, thus solving for thermal dissusivity κ = λ / (ρ c), wich will complete the set of parameters needed for a detailed description of thermal properties of the lunar regolith. Results of model calculations will be presented, in which synthetic data and calibration data are used to invert the unknown thermal diffusivity of the unknown medium by means of a modified Newton Method. Due to the ill-posedness of the problem, the number of parameters to be solved for should be limited. As the model calculations reveal, a homogeneous regolith allows for a fast and accurate inversion.

Formula one night race in Singapore: a 4-year analysis of a planned mass gathering.

PubMed

Ho, Weng Hoe; Koenig, Kristi L; Quek, Lit Sin

2014-10-01

Every mass gathering presents its unique characteristics that influence medical resource utilization. Medical planning for mass gatherings involves both use of predictive models and analysis of data from similar past events. This study aimed to describe the medical presentations and the unique challenges influencing medical planning at the Formula One Singtel Singapore Grand Prix, the inaugural Formula One night race. Patient presentation characteristics, rates of patient presentation, and transportation to hospitals in association with attendance and heat index were evaluated over a 4-year period from 2009 through 2012. This will facilitate medical planning for similar events. A database containing patient presentations from the 3-day Singapore Grand Prix in 2009, 2010, 2011, and 2012 was analyzed. Patient presentations were categorized by time of day and presenting complaints. Patient presentation rates (PPRs) were analyzed to determine correlation with attendance numbers and heat index. The average annual attendance at the Singapore Grand Prix was 81,992 from 2009 through 2012. The average PPR was 2.17 (SD=0.63)/1,000 attendees. The average transport to hospital rate (TTHR) was 0.033 (SD=0.026)/1,000 attendees. While medical coverage was provided at the circuit park between 2:00 pm to 1:00 am daily, most attendees presented from 5:00 pm to 10:00 pm. The most common presenting complaints included: musculoskeletal conditions (59%) and heat related illnesses (19%). There was no correlation between attendance numbers and PPR and the heat index and PPR. Musculoskeletal conditions and heat-related illnesses were the most common presenting complaints at the Singapore Grand Prix from 2009-2012. The lack of correlation between heat index and PPR is a new finding compared with prior studies. This could be due to the minimal heat variation that occurred during the night event. Further study is required to refine models that can be used in specialized events.

Creatine Use and Exercise Heat Tolerance in Dehydrated Men

PubMed Central

Watson, Greig; Casa, Douglas J; Fiala, Kelly A; Hile, Amy; Roti, Melissa W; Healey, Julie C; Armstrong, Lawrence E; Maresh, Carl M

2006-01-01

Context: Creatine monohydrate (CrM) use is highly prevalent in team sports (eg, football, lacrosse, ice hockey) and by athletes at the high school, college, professional, and recreational levels. Concerns have been raised about whether creatine use is associated with increased cramping, muscle injury, heat intolerance, and risk of dehydration. Objective: To assess whether 1 week of CrM supplementation would compromise hydration status, alter thermoregulation, or increase the incidence of symptoms of heat illness in dehydrated men performing prolonged exercise in the heat. Design: Double-blind, randomized, crossover design. Setting: Human Performance Laboratory. Patients or Other Participants: Twelve active males, age = 22 ± 1 year, height = 180 ± 3 cm, mass = 78.8 ± 1.2 kg, body fat = 9 ± 1%, V̇o2peak = 50.9 ± 1 ml·kg−1·min−1. Intervention(s): Subjects consumed 21.6 g·d−1 of CrM or placebo for 7 days, underwent 48 ± 10 days of washout between treatments, and then crossed over to the alternate treatment in the creatine group. On day 7 of each treatment, subjects lost 2% body mass by exercising in 33.5°C and then completed an 80-minute exercise heat-tolerance test (33.5°C ± 0.5°C, relative humidity = 41 ± 12%). The test consisted of four 20-minute sequences of 4 minutes of rest, alternating a 3-minute walk and 1-minute high-intensity run 3 times, and walking for 4 minutes. Main Outcome Measures: Thermoregulatory, cardiorespiratory, metabolic, urinary, and perceptual responses. Results: On day 7, body mass had increased 0.88 kg. No interaction or treatment differences for placebo versus CrM during the exercise heat-tolerance test were noted in thermoregulatory (rectal temperature, 39.3 ± 0.4°C versus 39.4 ± 0.4°C) cardiorespiratory (V̇o2, 21.4 ± 2.7 versus 20.0 ± 1.8 ml·kg−1·min−1; heart rate, 192 ± 10 versus 192 ± 11 beats·min−1; mean arterial pressure, 90 ± 9 versus 88 ± 5 mm Hg), metabolic (lactate, 6.7 ± 2.7 versus 7.0 ± 3.0 mmol·L−1), perceptual thirst (thirst, 7 ± 1 versus 7 ± 1; thermal sensation, 8 ± 2 versus 8 ± 1; rating of perceived exertion, 17 ± 3 versus 17 ± 2), plasma glucose (0–20 minutes of exercise heat-tolerance, 6.5 ± 1.2 versus 6.8 ± 0.8 mmol·L−1), plasma (297 ± 5 versus 300 ± 4 mOsm·kg−1) and urine (792 ± 117 versus 651 ± 134 mOsm·kg−1), urine specific gravity (1.025 ± 0.003 versus 1.030 ± 0.005) and urine color (7 ± 1 versus 6 ± 1) measures were increased during CrM. Environmental Symptoms Questionnaire scores were similar between treatments. The levels of dehydration incurred during dehydration and the exercise heat-tolerance test were similar and led to similar cumulative body mass losses (−4.09 ± 0.53 versus −4.38 ± 0.58% body mass). Conclusions: Short-term CrM supplementation did not increase the incidence of symptoms or compromise hydration status or thermoregulation in dehydrated, trained men exercising in the heat. PMID:16619091

Method for Molding Structural Parts Utilizing Modified Silicone Rubber

NASA Technical Reports Server (NTRS)

Weiser, Erik S. (Inventor); Baucom, Robert M. (Inventor); Snoha, John J. (Inventor)

1998-01-01

This invention improves upon a method for molding structural parts from preform material. Preform material to be used for the part is provided. A silicone rubber composition containing entrained air voids is prepared. The silicone rubber and preform material assembly is situated within a rigid mold cavity used to shape the preform material to die desired shape. The entire assembly is heated in a standard heating device so that the thermal expansion of the silicone rubber exerts the pressure necessary to force the preform material into contact with the mold container. The introduction of discrete air voids into the silicone rubber allows for accurately controlled pressure application on the preform material at the cure temperature.

Means for accommodating large overstrain in lead wires. [by storing extra length of wire in stretchable loop

NASA Technical Reports Server (NTRS)

Rumble, C. V.; Driscoll, K. L. (Inventor)

1974-01-01

An electrical wire is reported along whose length loops are formed at intervals and retained in a plastic capsule that allows unfolding of the loop when tension is exerted on the opposite ends of the wire. The capsule is formed by encompassing each loop with a sleeve of heat shrinkable synthetic plastic material which overlaps the loop and heat shrinking the overlapping portions. Thus, a length of electrical wire is formed which stores extra lengths of wire in the quantity needed to match the expected stretching of materials or elements such as ropes, cords and the like of high elongation to which the electrical wire may be attached.

Health impacts of workplace heat exposure: an epidemiological review.

PubMed

Xiang, Jianjun; Bi, Peng; Pisaniello, Dino; Hansen, Alana

2014-01-01

With predicted increasing frequency and intensity of extremely hot weather due to changing climate, workplace heat exposure is presenting an increasing challenge to occupational health and safety. This article aims to review the characteristics of workplace heat exposure in selected relatively high risk occupations, to summarize findings from published studies, and ultimately to provide suggestions for workplace heat exposure reduction, adaptations, and further research directions. All published epidemiological studies in the field of health impacts of workplace heat exposure for the period of January 1997 to April 2012 were reviewed. Finally, 55 original articles were identified. Manual workers who are exposed to extreme heat or work in hot environments may be at risk of heat stress, especially those in low-middle income countries in tropical regions. At risk workers include farmers, construction workers, fire-fighters, miners, soldiers, and manufacturing workers working around process-generated heat. The potential impacts of workplace heat exposure are to some extent underestimated due to the underreporting of heat illnesses. More studies are needed to quantify the extent to which high-risk manual workers are physiologically and psychologically affected by or behaviourally adapt to workplace heat exposure exacerbated by climate change.

Health Impacts of Workplace Heat Exposure: An Epidemiological Review

PubMed Central

XIANG, Jianjun; BI, Peng; PISANIELLO, Dino; HANSEN, Alana

2013-01-01

With predicted increasing frequency and intensity of extremely hot weather due to changing climate, workplace heat exposure is presenting an increasing challenge to occupational health and safety. This article aims to review the characteristics of workplace heat exposure in selected relatively high risk occupations, to summarize findings from published studies, and ultimately to provide suggestions for workplace heat exposure reduction, adaptations, and further research directions. All published epidemiological studies in the field of health impacts of workplace heat exposure for the period of January 1997 to April 2012 were reviewed. Finally, 55 original articles were identified. Manual workers who are exposed to extreme heat or work in hot environments may be at risk of heat stress, especially those in low-middle income countries in tropical regions. At risk workers include farmers, construction workers, fire-fighters, miners, soldiers, and manufacturing workers working around process-generated heat. The potential impacts of workplace heat exposure are to some extent underestimated due to the underreporting of heat illnesses. More studies are needed to quantify the extent to which high-risk manual workers are physiologically and psychologically affected by or behaviourally adapt to workplace heat exposure exacerbated by climate change. PMID:24366537

The Impact of Heat Exposure and Sleep Restriction on Firefighters' Work Performance and Physiology during Simulated Wildfire Suppression.

PubMed

Vincent, Grace E; Aisbett, Brad; Larsen, Brianna; Ridgers, Nicola D; Snow, Rod; Ferguson, Sally A

2017-02-12

This study was designed to examine the effects of ambient heat on firefighters' physical task performance, and physiological and perceptual responses when sleep restricted during simulated wildfire conditions. Thirty firefighters were randomly allocated to the sleep restricted ( n = 17, SR; 19 °C, 4-h sleep opportunity) or hot and sleep restricted ( n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Firefighters performed two days of simulated, intermittent, self-paced work circuits comprising six firefighting tasks. Heart rate, and core temperature were measured continuously. After each task, firefighters reported their rating of perceived exertion and thermal sensation. Effort sensation was also reported after each work circuit. Fluids were consumed ad libitum. Urine volume and urine specific gravity were analysed. Sleep was monitored using polysomnography. There were no differences between the SR and HOT + SR groups in firefighters' physiological responses, hydration status, ratings of perceived exertion, motivation, and four of the six firefighting tasks (charged hose advance, rake, hose rolling, static hose hold). Black out hose and lateral repositioning were adversely affected in the HOT + SR group. Working in hot conditions did not appear to consistently impair firefighters work performance, physiology, and perceptual responses. Future research should determine whether such findings remain true when individual tasks are performed over longer durations.

Is muscle energy production disturbed in exertional heat stroke?

PubMed

Sagui, Emmanuel; Abriat, Amandine; Kozak-Ribbens, Geneviève; Foutrier-Morello, Catherine; Bernard, Monique; Canini, Frédéric; Brosset, Christian; Bendahan, David

2014-03-01

Exertional heat stroke (EHS) is a life-threatening disease that shares some clinical similarities with malignant hyperthermia (MH). By use of (31)Phosphorus magnetic resonance spectroscopy (MRS), EHS patients with MH susceptibility and MH patients shared common metabolic abnormalities. The aim of this study was to determine whether subjects who suffered from an EHS episode had disturbed muscle energetics. This retrospective study was performed within the French database of military subjects that were explored from 2004 to 2010 after they suffered an EHS. All subjects had both in vitro contracture test to determine their MH susceptibility and (31)Phosphorus MRS at 4.7 Tesla to assess muscle energetics by means of MRS score, a composite score corresponding to the sum of metabolic abnormalities recorded during a standardized rest-exercise-recovery protocol. 437 subjects were investigated and 32.5% of them exhibited abnormal MRS score. MRS score did not segregate subjects on demographic, clinical, or biological grounds. No clear correlation could be done between MH status and MRS score. These results did not confirm the potential relationship between calcium homeostasis and muscle energetics previously reported. However, muscle energy production was disturbed in a significant number of EHS subjects. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

Exercise collapse associated with sickle cell trait (ECAST): case report and literature review.

PubMed

Quattrone, Richard D; Eichner, E Randy; Beutler, Anthony; Adams, W Bruce; O'Connor, Francis G

2015-01-01

Sickle cell trait (SCT) has been associated with exertional collapse (ECAST) and exercise-related sudden death in athletes and military warfighters. The mechanisms underlying ECAST remain controversial in the sports medicine community. Multiple case presentations and anecdotal reports postulate the role of extraordinary exercise intensity, but other risk factors including dehydration, heat, previous exertional rhabdomyolysis, genetic cofactors, and dietary supplements have been cited as potential contributors. Others have hypothesized some of the aforementioned factors combining in a "perfect storm" to trigger ECAST with a resultant potentially fatal "metabolic crisis." This case report provides a brief review of SCT as it pertains to exercise in warfighters and athletes, identifies known and postulated risk factors associated with ECAST, and introduces the potential mechanistic role of the "double hit" as a contributor to ECAST.

Human heat adaptation.

PubMed

Taylor, Nigel A S

2014-01-01

In this overview, human morphological and functional adaptations during naturally and artificially induced heat adaptation are explored. Through discussions of adaptation theory and practice, a theoretical basis is constructed for evaluating heat adaptation. It will be argued that some adaptations are specific to the treatment used, while others are generalized. Regarding ethnic differences in heat tolerance, the case is put that reported differences in heat tolerance are not due to natural selection, but can be explained on the basis of variations in adaptation opportunity. These concepts are expanded to illustrate how traditional heat adaptation and acclimatization represent forms of habituation, and thermal clamping (controlled hyperthermia) is proposed as a superior model for mechanistic research. Indeed, this technique has led to questioning the perceived wisdom of body-fluid changes, such as the expansion and subsequent decay of plasma volume, and sudomotor function, including sweat habituation and redistribution. Throughout, this contribution was aimed at taking another step toward understanding the phenomenon of heat adaptation and stimulating future research. In this regard, research questions are posed concerning the influence that variations in morphological configuration may exert upon adaptation, the determinants of postexercise plasma volume recovery, and the physiological mechanisms that modify the cholinergic sensitivity of sweat glands, and changes in basal metabolic rate and body core temperature following adaptation. © 2014 American Physiological Society.

Linking lowermost mantle structure, core-mantle boundary heat flux and mantle plume formation

NASA Astrophysics Data System (ADS)

Li, Mingming; Zhong, Shijie; Olson, Peter

2018-04-01

The dynamics of Earth's lowermost mantle exert significant control on the formation of mantle plumes and the core-mantle boundary (CMB) heat flux. However, it is not clear if and how the variation of CMB heat flux and mantle plume activity are related. Here, we perform geodynamic model experiments that show how temporal variations in CMB heat flux and pulses of mantle plumes are related to morphologic changes of the thermochemical piles of large-scale compositional heterogeneities in Earth's lowermost mantle, represented by the large low shear velocity provinces (LLSVPs). We find good correlation between the morphologic changes of the thermochemical piles and the time variation of CMB heat flux. The morphology of the thermochemical piles is significantly altered during the initiation and ascent of strong mantle plumes, and the changes in pile morphology cause variations in the local and the total CMB heat flux. Our modeling results indicate that plume-induced episodic variations of CMB heat flux link geomagnetic superchrons to pulses of surface volcanism, although the relative timing of these two phenomena remains problematic. We also find that the density distribution in thermochemical piles is heterogeneous, and that the piles are denser on average than the surrounding mantle when both thermal and chemical effects are included.

Plasma Wave Turbulence and Particle Heating Caused by Electron Beams, Radiation and Pinches.

DTIC Science & Technology

1982-05-01

Eq. (1) gives the quasi- longitudinal disier si i type-Ill solar radio hursts . ’i for the radar-modified relation for an oblique Langni i.-.ave...Detailed cot’" irisons are miade v. oh (other i-ditsol models of-strong" Langmuir turbulence associated with type Ill hurst -s 1. INTRODUCTION Zakharov...1,1;, Ail ft oscillites abtout :in averaige v~uims that tiv,’ri expon - (ti v h. (1’-25, andn (c) s- 6. 412!t1. ev~w, , enti:,t in time’. lioi, ,-t

Non-heat-treated frozen raspberries the most likely vehicle of a norovirus outbreak in Oslo, Norway, November 2013.

PubMed

Einöder-Moreno, M; Lange, H; Grepp, M; Osborg, E; Vainio, K; Vold, L

2016-10-01

In November 2013, the Norwegian Institute of Public Health was notified of a gastroenteritis outbreak following two meetings held at a conference centre. Identical food and beverages were served during the meetings. We investigated in order to identify the vehicle of infection and implement control measures. Meeting participants completed an online questionnaire on consumption of foods and beverages. We asked symptomatic participants to provide a stool sample. We defined a case as diarrhoea and/or vomiting in a participant who became ill within 3 days after the meeting. We calculated attack rates (AR) and adjusted risk ratios (aRR) with 95% confidence intervals (CI) using binomial regression. We conducted environmental investigations. Overall, 147/168 (88%) participants responded, of which 74 (50%) met the case definition. All five stool samples provided were norovirus positive. No kitchen staff reported being sick. Risk of illness was higher in those who consumed raspberry mousse (aRR 3·4, 95% CI 1·4-8·2) and sliced fresh fruit (aRR 1·9, 95% CI 1·3-2·8). Seventy cases (95%) ate raspberry mousse. Frozen raspberries used for the mousse were imported and not heat-treated before consumption. Non-heat-treated frozen raspberries were the most likely outbreak vehicle. Contamination by a food handler could not be excluded. We recommend heat-treatment of imported frozen berries before consumption.

Passive cigarette smoke, coal heating, and respiratory symptoms of nonsmoking women in China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pope, C.A. III; Xu, X.

1993-09-01

In this study the authors evaluated data from a sample of 973 never-smoking women, ages 20-40, who worked in three similar textile mills in Anhui Province, China. They compared prevalence rates of respiratory symptoms across homes with and without coal heating and homes with different numbers of smokers. Multiple logistic regression models that controlled for age, job title, and mill of employment were also estimated. Respiratory symptoms were associated with combined exposure to passive cigarette smoke and coal heating. Effects of passive cigarette smoke and coal heating on respiratory symptoms appeared to be nearly additive, suggesting a dose-response relationship betweenmore » respiratory symptoms and home indoor air pollution from these two sources. The prevalence of chest illness, cough, phlegm, and shortness of breath (but not wheeze) was significantly elevated for women living in homes with both smokers and coal heating.« less

Intestinal epithelial barrier function and tight junction proteins with heat and exercise

PubMed Central

Zuhl, Micah N.; Moseley, Pope L.

2015-01-01

A single layer of enterocytes and tight junctions (intercellular multiprotein complexes) form the intestinal epithelial barrier that controls transport of molecules through transcellular and paracellular pathways. A dysfunctional or “leaky” intestinal tight junction barrier allows augmented permeation of luminal antigens, endotoxins, and bacteria into the blood stream. Various substances and conditions have been shown to affect the maintenance of the intestinal epithelial tight junction barrier. The primary focus of the present review is to analyze the effects of exertional or nonexertional (passive hyperthermia) heat stress on tight junction barrier function in in vitro and in vivo (animals and humans) models. Our secondary focus is to review changes in tight junction proteins in response to exercise or hyperthermic conditions. Finally, we discuss some pharmacological or nutritional interventions that may affect the cellular mechanisms involved in maintaining homeostasis of the intestinal epithelial tight junction barrier during heat stress or exercise. PMID:26359485

Small-angle x-ray scattering investigation of the effect of heating temperature on the submicroscopic pore structure of wood charcoal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidt, P.W.; Cutter, B.E.; Kalliat, M.

1984-04-01

In order to learn about the effects of higher preparation temperatures, we recently examined a series of charcoals from black cherry (Prunus serotina Ehrh.) wood heated to temperatures from 600/sup 0/ to 2000/sup 0/C. The results are summarized in this report. In addition to obtaining some information about the pore structure of black cherry charcoal, we have developed a general picture of how the charcoal porosity depends on the temperature to which the wood was heated during pyrolysis. These results have led us to propose that the macropores in charcoals are similar to those in wood and that the mainmore » effect which pyrolysis at temperatures above 400/sup 0/C exerts on the pore structure is to cause the micropores and transitional pores to grow, while leaving the macropores almost unchanged.« less

Intestinal epithelial barrier function and tight junction proteins with heat and exercise.

PubMed

Dokladny, Karol; Zuhl, Micah N; Moseley, Pope L

2016-03-15

A single layer of enterocytes and tight junctions (intercellular multiprotein complexes) form the intestinal epithelial barrier that controls transport of molecules through transcellular and paracellular pathways. A dysfunctional or "leaky" intestinal tight junction barrier allows augmented permeation of luminal antigens, endotoxins, and bacteria into the blood stream. Various substances and conditions have been shown to affect the maintenance of the intestinal epithelial tight junction barrier. The primary focus of the present review is to analyze the effects of exertional or nonexertional (passive hyperthermia) heat stress on tight junction barrier function in in vitro and in vivo (animals and humans) models. Our secondary focus is to review changes in tight junction proteins in response to exercise or hyperthermic conditions. Finally, we discuss some pharmacological or nutritional interventions that may affect the cellular mechanisms involved in maintaining homeostasis of the intestinal epithelial tight junction barrier during heat stress or exercise. Copyright © 2016 the American Physiological Society.

Joule heating effects on particle immobilization in insulator-based dielectrophoretic devices.

PubMed

Gallo-Villanueva, Roberto C; Sano, Michael B; Lapizco-Encinas, Blanca H; Davalos, Rafael V

2014-02-01

In this work, the temperature effects due to Joule heating obtained by application of a direct current electric potential were investigated for a microchannel with cylindrical insulating posts employed for insulator-based dielectrophoresis. The conductivity of the suspending medium, the local electric field, and the gradient of the squared electric field, which directly affect the magnitude of the dielectrophoretic force exerted on particles, were computationally simulated employing COMSOL Multiphysics. It was observed that a temperature gradient is formed along the microchannel, which redistributes the conductivity of the suspending medium leading to an increase of the dielectrophoretic force toward the inlet of the channel while decreasing toward the outlet. Experimental results are in good agreement with simulations on the particle-trapping zones anticipated. This study demonstrates the importance of considering Joule heating effects when designing insulator-based dielectrophoresis systems. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adaptations and mechanisms of human heat acclimation: Applications for competitive athletes and sports.

PubMed

Périard, J D; Racinais, S; Sawka, M N

2015-06-01

Exercise heat acclimation induces physiological adaptations that improve thermoregulation, attenuate physiological strain, reduce the risk of serious heat illness, and improve aerobic performance in warm-hot environments and potentially in temperate environments. The adaptations include improved sweating, improved skin blood flow, lowered body temperatures, reduced cardiovascular strain, improved fluid balance, altered metabolism, and enhanced cellular protection. The magnitudes of adaptations are determined by the intensity, duration, frequency, and number of heat exposures, as well as the environmental conditions (i.e., dry or humid heat). Evidence is emerging that controlled hyperthermia regimens where a target core temperature is maintained, enable more rapid and complete adaptations relative to the traditional constant work rate exercise heat acclimation regimens. Furthermore, inducing heat acclimation outdoors in a natural field setting may provide more specific adaptations based on direct exposure to the exact environmental and exercise conditions to be encountered during competition. This review initially examines the physiological adaptations associated with heat acclimation induction regimens, and subsequently emphasizes their application to competitive athletes and sports. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Review article: Environmental heatstroke and long-term clinical neurological outcomes: A literature review of case reports and case series 2000-2016.

PubMed

Lawton, Emily M; Pearce, Helen; Gabb, Genevieve M

2018-05-31

Global temperatures are rising; extreme environmental heat can result in adverse health effects including heatstroke. Acute effects of heat are well recognised, but there is less understanding of potential long-term adverse outcomes. Our aim was to review recent medical literature for clinical cases of environmental heatstroke with a focus on neurological outcome. Structured search strategies were designed to retrieve publications of heatstroke case reports using Ovid Medline and Embase (2000-2016). One thousand and forty-nine abstracts were identified, and after application of exclusion criteria 71 articles deemed relevant. Ninety cases were identified from 71 articles. 100% presented with acute neurological symptoms; 87.8% presented with non-neurological symptoms. 44.4% patients recovered fully, 23.3% died, 23.3% suffered convalescent or long-term neurological sequelae, and in 8.9% no long-term follow up was available. 57.1% of the patients who died or had a neurological deficit had no documented co-morbidity. Patterns of neurological deficits included 66.7% patients with motor dysfunction, 9.5% cognitive impairment, 19% both motor and cognitive impairment and 4.7% other. In total 71.4% of the impaired patients had long-term cerebellar dysfunction. Adverse long-term neurological outcomes were common in surviving patients presenting with environmental heatstroke. Permanent neurological deficits were present in 34.4% of survivors where outcome was known; many were young, healthy individuals. Cerebellar injury was common suggesting cerebellar structures are vulnerable to heat. These findings highlight that people of all ages and pre-morbid states are at risk of severe heat-related illness. In the face of climate change, effective interventions for heat-related illness, including both treatment and prevention are necessary. © 2018 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Evaluation of Diagnostic Codes in Morbidity and Mortality Data Sources for Heat-Related Illness Surveillance

PubMed Central

Watkins, Sharon

2017-01-01

Objectives: The primary objective of this study was to identify patients with heat-related illness (HRI) using codes for heat-related injury diagnosis and external cause of injury in 3 administrative data sets: emergency department (ED) visit records, hospital discharge records, and death certificates. Methods: We obtained data on ED visits, hospitalizations, and deaths for Florida residents for May 1 through October 31, 2005-2012. To identify patients with HRI, we used codes from the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) to search data on ED visits and hospitalizations and codes from the International Classification of Diseases, Tenth Revision (ICD-10) to search data on deaths. We stratified the results by data source and whether the HRI was work related. Results: We identified 23 981 ED visits, 4816 hospitalizations, and 140 deaths in patients with non–work-related HRI and 2979 ED visits, 415 hospitalizations, and 23 deaths in patients with work-related HRI. The most common diagnosis codes among patients were for severe HRI (heat exhaustion or heatstroke). The proportion of patients with a severe HRI diagnosis increased with data source severity. If ICD-9-CM code E900.1 and ICD-10 code W92 (excessive heat of man-made origin) were used as exclusion criteria for HRI, 5.0% of patients with non–work-related deaths, 3.0% of patients with work-related ED visits, and 1.7% of patients with work-related hospitalizations would have been removed. Conclusions: Using multiple data sources and all diagnosis fields may improve the sensitivity of HRI surveillance. Future studies should evaluate the impact of converting ICD-9-CM to ICD-10-CM codes on HRI surveillance of ED visits and hospitalizations. PMID:28379784

Cortisol and interleukin-6 responses during intermittent exercise in two different hot environments with equivalent WBGT.

PubMed

Wright, Heather E; McLellan, Tom M; Stapleton, Jill M; Hardcastle, Stephen G; Kenny, Glen P

2012-01-01

Blood marker concentrations such as cortisol (COR) and interleukin (IL)-6 are commonly used to evaluate the physiological strain associated with work in the heat. It is unclear, however, if hot environments of an equivalent thermal stress, as defined by a similar wet bulb globe temperature (WBGT), result in similar response patterns. This study examined markers of neuroendocrine (COR) and immune (IL-6) responses, as well as the cardiovascular and thermal responses, relative to changes in body heat content measured by whole-body direct calorimetry during work in two different hot environments with equivalent WBGT. Eight males performed a 2-hr heavy intermittent exercise protocol (six 15-min bouts of cycling at a constant rate of metabolic heat production (360W) interspersed by 5-min rest periods) in Hot/Dry (46°C, 10% relative humidity [RH]) and Warm/Humid (33°C, 60% RH) conditions (WBGT ∼ 29°C). Whole-body evaporative and dry heat exchange, change in body heat content (ΔH(b)), rectal temperature (T(re)), and heart rate were measured continuously. Venous blood was obtained at rest (PRE) and the end of each exercise bout for the measurement of changes in plasma volume (PV), plasma protein (an estimate of plasma water changes), COR, and IL-6. Ratings of perceived exertion and thermal sensation were measured during the last minute of each exercise bout. No differences existed for ΔH(b), heart rate, T(re),%ΔPV, plasma protein concentration, perceptual strain (thermal sensation, perceived exertion), and COR between the Hot/Dry and Warm/Humid conditions. IL-6 exhibited an interaction effect (p = 0.041), such that greater increases were observed in the Hot/Dry (Δ = 1.61 pg·mL(-1)) compared with the Warm/Humid (Δ = 0.64 pg·mL(-1)) environment. These findings indicate that work performed in two different hot environments with equivalent WBGT resulted in similar levels of thermal, cardiovascular, and perceptual strain, which support the use of the WBGT stress index. However, the greater IL-6 response in the Hot/Dry requires further research to elucidate the effects of different hot environments and work intensities.

The effect of ice slushy ingestion and mouthwash on thermoregulation and endurance performance in the heat.

PubMed

Burdon, Catriona A; Hoon, Matthew W; Johnson, Nathan A; Chapman, Phillip G; O'Connor, Helen T

2013-10-01

The purpose of this study was to establish whether sensory factors associated with cold-beverage ingestion exert an ergogenic effect on endurance performance independent of thermoregulatory or cardiovascular factors. Ten males performed three trials involving 90 min of steady state cycling (SS; 62% VO2max) in the heat (32.1 ± 0.9 °C, 40 ± 2.4% relative humidity) followed by a 4 kJ/kg body mass time trial (TT). During SS, participants consumed an identical volume (260 ± 38 g) of sports beverage (7.4% carbohydrate) every 15 min as either ice slushy (-1 °C; ICE), thermoneutral liquid (37 °C; CON), or thermoneutral liquid consumption with expectorated ice slushy mouthwash (WASH). Rectal temperature, hydration status, heart rate, and skin blood flow were not different between trials. Gastrointestinal (pill) temperature was lower in ICE (35.6 ± 2.7 °C) versus CON (37.4 ± 0.7 °C, p = .05). Heat storage tended to be lower with ICE during SS (14.7 ± 8.4 W.m(-2), p = .08) and higher during TT (68.9 ± 38.6 W.m(-2), p = .03) compared with CON (22.1 ± 6.6 and 31.4 ± 27.6 W.m(-2)). ICE tended to lower the rating of perceived exertion (RPE, 12.9 ± 0.6, p = .05) and improve thermal comfort (TC, 4.5 ± 0.2; p = .01) vs. CON (13.8 ± 1.0 and 5.2 ± 0.2 respectively). WASH RPE (13.0 ± 0.8) and TC (4.8 ± 0.2) tended to be lower versus CON (p = .07 and p = .09 respectively). ICE improved performance (18:28 ± 1:03) compared with CON (20:24 ± 1:46) but not WASH (19:45 ± 1:43). Improved performance with ICE ingestion likely resulted from the creation of a gastrointestinal heat sink, reducing SS heat storage. Although the benefits of cold-beverage consumption are more potent when there is ingestion, improved RPE, TC, and meaningful performance improvement with WASH supports an independent sensory effect of presenting a cold stimulus to the mouth.

Preparing for Travel in India.

ERIC Educational Resources Information Center

Oswald, James M.

The complexity of the Indian society can be overwhelming, and preparation for travel in India requires careful and detailed advance planning. Practical suggestions are provided for travelers to help them understand cultural differences, avoid illnesses, and select appropriate clothing for the intense heat. Explanations are given about the monetary…

Heat Illness - Multiple Languages

MedlinePlus

... sharing features on this page, please enable JavaScript. Arabic (العربية) Bosnian (bosanski) Haitian Creole (Kreyol ayisyen) Modern Standard Arabic (Arabic dialect) (العربية الفصحى, عربي فصيح) Somali (Af- ...

Age of onset of bipolar disorder: Combined effect of childhood adversity and familial loading of psychiatric disorders.

PubMed

Post, Robert M; Altshuler, Lori L; Kupka, Ralph; McElroy, Susan L; Frye, Mark A; Rowe, Michael; Grunze, Heinz; Suppes, Trisha; Keck, Paul E; Leverich, Gabriele S; Nolen, Willem A

2016-10-01

Family history and adversity in childhood are two replicated risk factors for early onset bipolar disorder. However, their combined impact has not been adequately studied. Based on questionnaire data from 968 outpatients with bipolar disorder who gave informed consent, the relationship and interaction of: 1) parental and grandparental total burden of psychiatric illness; and 2) the degree of adversity the patient experienced in childhood on their age of onset of bipolar disorder was examined with multiple regression and illustrated with a heat map. The familial loading and child adversity vulnerability factors were significantly related to age of onset of bipolar and their combined effect was even larger. A heat map showed that at the extremes (none of each factor vs high amounts of both) the average age of onset differed by almost 20 years (mean = 25.8 vs 5.9 years of age). The data were not based on interviews of family members and came from unverified answers on a patient questionnaire. Family loading for psychiatric illness and adversity in childhood combine to have a very large influence on age of onset of bipolar disorder. These variables should be considered in assessment of risk for illness onset in different populations, the need for early intervention, and in the design of studies of primary and secondary prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.

JACKETING URANIUM

DOEpatents

Saller, H.A.; Keeler, J.R.

1959-07-14

The bonding to uranium of sheathing of iron or cobalt, or nickel, or alloys thereof is described. The bonding is accomplished by electro-depositing both surfaces to be joined with a coating of silver and amalgamating or alloying the silver layer with mercury or indium. Then the silver alloy is homogenized by exerting pressure on an assembly of the uranium core and the metal jacket, reducing the area of assembly and heating the assembly to homogenize by diffusion.

Prevention of Organ Injury in Exertional Heat Stroke: Preclinical Evaluation of a New Class of NSAIDs

DTIC Science & Technology

2017-10-01

and integration of data from 3 centers. PROGRESS: All of year one goals were completed except for completion of the manuscripts, which are...samples from mice, integrate data collection from the 3 laboratories and prepare final reports and manuscripts of experimental outcomes. PROGRESS...the later recovery period. These data suggest some abnormalities in glucose metabolism, particularly in male mice, during the recovery from EHS

[Sports and heat stroke].

PubMed

Yuzawa, Itsuki; Miyake, Yasufumi; Aruga, Tohru

2012-06-01

We described Characteristic of the heat stroke in the sports activity in Japan. It was common in teenage men, and 15 years old had a peak with a man, the woman. Most patients did not need specific treatment. Many happened from the end of July on the outdoors around 3:00 p.m. in mid-August. There are many in order of baseball, football, tennis, and a basketball. Running and cycling had high severity of illness. Probably, grasp of an environmental condition, suitable sportswear, suitable hydration, and condition management are the best things as preventive measures.

Inverse Heat Conduction Methods in the CHAR Code for Aerothermal Flight Data Reconstruction

NASA Technical Reports Server (NTRS)

Oliver, A. Brandon; Amar, Adam J.

2016-01-01

Reconstruction of flight aerothermal environments often requires the solution of an inverse heat transfer problem, which is an ill-posed problem of determining boundary conditions from discrete measurements in the interior of the domain. This paper will present the algorithms implemented in the CHAR code for use in reconstruction of EFT-1 flight data and future testing activities. Implementation details will be discussed, and alternative hybrid-methods that are permitted by the implementation will be described. Results will be presented for a number of problems.

Inverse Heat Conduction Methods in the CHAR Code for Aerothermal Flight Data Reconstruction

NASA Technical Reports Server (NTRS)

Oliver, A Brandon; Amar, Adam J.

2016-01-01

Reconstruction of flight aerothermal environments often requires the solution of an inverse heat transfer problem, which is an ill-posed problem of specifying boundary conditions from discrete measurements in the interior of the domain. This paper will present the algorithms implemented in the CHAR code for use in reconstruction of EFT-1 flight data and future testing activities. Implementation nuances will be discussed, and alternative hybrid-methods that are permitted by the implementation will be described. Results will be presented for a number of one-dimensional and multi-dimensional problems

Convective and Stratiform Precipitation Processes and their Relationship to Latent Heating

NASA Technical Reports Server (NTRS)

Tao, Wei-Kuo; Lang, Steve; Zeng, Xiping; Shige, Shoichi; Takayabu, Yukari

2009-01-01

The global hydrological cycle is central to the Earth's climate system, with rainfall and the physics of its formation acting as the key links in the cycle. Two-thirds of global rainfall occurs in the Tropics. Associated with this rainfall is a vast amount of heat, which is known as latent heat. It arises mainly due to the phase change of water vapor condensing into liquid droplets; three-fourths of the total heat energy available to the Earth's atmosphere comes from tropical rainfall. In addition, fresh water provided by tropical rainfall and its variability exerts a large impact upon the structure and motions of the upper ocean layer. An improved convective -stratiform heating (CSH) algorithm has been developed to obtain the 3D structure of cloud heating over the Tropics based on two sources of information: 1) rainfall information, namely its amount and the fraction due to light rain intensity, observed directly from the Precipitation Radar (PR) on board the TRMM satellite and 2) synthetic cloud physics information obtained from cloud-resolving model (CRM) simulations of cloud systems. The cloud simulations provide details on cloud processes, specifically latent heating, eddy heat flux convergence and radiative heating/cooling, that. are not directly observable by satellite. The new CSH algorithm-derived heating has a noticeably different heating structure over both ocean and land regions compared to the previous CSH algorithm. One of the major differences between new and old algorithms is that the level of maximum cloud heating occurs 1 to 1.5 km lower in the atmosphere in the new algorithm. This can effect the structure of the implied air currents associated with the general circulation of the atmosphere in the Tropics. The new CSH algorithm will be used provide retrieved heating data to other heating algorithms to supplement their performance.

Psychosocial primary care – what patients expect from their General Practitioners A cross-sectional trial

PubMed Central

Fritzsche, Kurt; Armbruster, Ulrike; Hartmann, Armin; Wirsching, Michael

2002-01-01

Background Psychosocial Primary Care (PPC) is a model of service delivery for patients with mental disorders and psychosocial problems which was established in Germany in 1987. This study was performed as part of the evaluation of a PPC training program. We investigated patients' expectations of the psychosocial treatment offered by GPs trained in PPC. Methods Ten general practitioners trained in PPC were randomly selected. Two hundred and twenty patients were surveyed in the waiting room regarding their expectations concerning psychological treatment. Results Eighty-five per cent of patients could envisage making use of psychosocial treatments. Counselling by the GP was considered most important (65%). Fifty-four per cent of patients indicated that there was sufficient counselling, but further distinctions revealed dissatisfaction with both the extent and content of the counselling. Lack of time was the most frequent reason (53%) cited for insufficient counselling. A willingness to discuss the psychological aspects of illness was exhibited by between 55% (current illness) and 79% of patients. Two-thirds of patients believed that discussing psychological aspects and counselling by the doctor could exert a healing effect or contribute to symptomatic improvement in physical illnesses. Younger patients and patients with experience in psychotherapy expected referral to mental health services. Conclusions Primary care patients desire and accept psychological treatment from their GP. Training in psychosocial competence in primary care should be offered more frequently. PMID:12000687

Family relations and health over the life course. A Lebanese perspective.

PubMed

Ajrouch, Kristine J; Abdulrahim, Sawsan; Antonucci, Toni C

2015-01-01

The link between family relations and well-being in old age has received ample attention in the international literature, but remains least examined in the Arab region where cultural ideals assume positive intergenerational relations within families as the norm. In this paper, we employ survey data collected in Greater Beirut in 2009 to explore associations between family relations and health. over the life course. We tested (1) the extent to which age and social relation characteristics predict health; and (2) whether the association between age and health is stronger for those who report: smaller social networks and poorer relationship quality. We employed self-rated health and self-reported chronic illness as the health outcome measures and:social network size, positive quality and negative quality with family members as the social relations measures. Our findings suggest that social relations are differentially important depending on the health status indicator examined. The single dimension that influenced both self-rated health and the probability of reporting a chronic illness was positive relationship quality with spouse. Further, social relations, particularly having a negative relationship quality with spouse and adult child, exert stronger effects on both self-rated health and chronic illness for older compared to younger adults. The findings of the present study are important for clinical practitioners who often consider the role and importance of available social resources as they address the health needs of older adults.

Three year stability of Five-Factor Model personality traits in relation to changes in symptom levels in patients with schizophrenia or related disorders.

PubMed

Boyette, Lindy-Lou; Nederlof, Jan; Meijer, Carin; de Boer, Froukje; de Haan, Lieuwe

2015-09-30

Five-Factor Model (FFM) personality traits are related to a wide range of clinical outcome in patients with psychotic disorders. However, it is not sufficiently clear whether psychotic illness, particularly fluctuation in negative symptoms and psychotic relapse, affects personality. The current study examined the 3-year temporal stability of FFM traits in 91 patients with non-affective psychotic disorders with a maximum duration of illness of 10 years and 32 control subjects without a (family member with) a diagnosis of psychotic illness. In patients, change in negative symptoms predicted changes in Neuroticism and (inversely) in Extraversion and Openness. However, when correcting for depressive symptoms, negative symptoms no longer predicted change in any FFM trait. Clinical characteristics, such as psychotic relapse, were also not found to be related to change in FFM traits. Patients showed a slight increase in Conscientiousness levels, the other FFM traits showed mean-level stability. Rank-order stability of the FFM traits was moderate to strong, although weaker for Neuroticism in patients. Our findings indicate that psychotic symptoms exert limited effect on the stability of FFM traits in patients with psychotic disorders. Consistent with general population findings, one should guard against state-trait confusion between Neuroticism/Extraversion and depression. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Analyses of Helsinki 2012 European Athletics Championships injury and illness surveillance to discuss elite athletes risk factors.

PubMed

Edouard, Pascal; Depiesse, Frédéric; Branco, Pedro; Alonso, Juan-Manuel

2014-09-01

To further analyze newly incurred injuries and illnesses (I&Is) during Athletics International Championships to discuss risk factors. Prospective recording of newly occurred injuries and illnesses. The 2012 European Athletics (EA) Championships in Helsinki, Finland. National team and local organizing committee physicians and physiotherapists and 1342 registered athletes. Incidence and characteristics of new injuries and illnesses. Ninety-three percent of athletes were covered by medical teams, with a response rate of 91%. One hundred thirty-three injuries were reported (incidence of 98.4 injuries per 1000 registered athletes). Sixty-two injuries (47%) resulted in time loss from sport. The most common diagnosis was hamstring strain (11.4% of injuries and 21% of time-loss injuries). Injury risk was higher in males and increased with age. The highest incidences of injuries were found in combined events and middle- and long-distance events. Twenty-seven illnesses were reported (4.0 illnesses per 1000 athlete days). The most common diagnoses were upper respiratory tract infection (33.3%) and gastroenteritis/diarrhea (25.9%). During outdoor EA Championships, injury and illness incidences were slightly lower and injury characteristics were comparable with those during outdoor World Athletics Championships. During elite athletics Championships, gender (male), age (older than 30 years), finals, and some events (combined events and middle- and long-distance races) seem to be injury risk factors. Illness risk factors remain unclear. As in previous recommendations, preventive interventions should focus on overuse injuries, hamstring strains, and adequate rehabilitation of previous injuries, decreasing risk of infectious diseases transmission, appropriate event scheduling, sports clothes, and heat acclimatization.

Occurrence of injuries and illnesses during the 2009 IAAF World Athletics Championships.

PubMed

Alonso, Juan-Manuel; Tscholl, Philippe M; Engebretsen, Lars; Mountjoy, Margo; Dvorak, Jiri; Junge, Astrid

2010-12-01

To analyse the frequency and characteristics of sports injuries and illnesses incurred during the World Athletics Championships. Prospective recording of newly occurred injuries and illnesses. Twelfth International Association of Athletics Federations World Championships in Athletics 2009 in Berlin, Germany. National team physicians and physiotherapists and 1979 accredited athletes; Local Organising Committee physicians working in the Medical Centres. Incidence and characteristics of newly incurred injuries and illnesses. 236 injury incidents with 262 injured body parts and 269 different injury types were reported, representing an incidence of 135.4 injuries per 1000 registered athletes. Eighty percent affected the lower extremity. Thigh strain (13.8%) was the main diagnosis. Overuse (44.1%) was the predominant cause. Most injuries were incurred during competition (85.9%). About 43.8% of all injury events were expected to result in time-loss. 135 illnesses were reported, signifying an incidence of 68.2 per 1000 registered athletes. Upper respiratory tract infection was the most common condition (30.4%) and infection was the most frequent cause (32.6%). The incidence of injury and illnesses varied substantially among the events. The risk of injury varied with each discipline. Preventive measures should be specific and focused on minimising the potential for overuse. Attention should be paid to ensure adequate rehabilitation of previous injuries. The addition of the illness part to the injury surveillance system proved to be feasible. As most illnesses were caused by infection of the respiratory tract or were environmentally related, preventive interventions should focus on decreasing the risk of transmission, appropriate event scheduling and heat acclimatisation.

[Dignity in the care of terminal ill and dying patients. Definitions and supportive interventions in palliative care].

PubMed

Mehnert, A; Schröder, A S; Puhlmann, K; Müllerleile, U; Koch, U

2006-11-01

Most patients, family members, health care professional as well as volunteers would agree that dignified care and being allowed to die with dignity are superior and unquestionable goals of palliative care. Although the majority of people have a more or less vague concept of dignity and despite its significance for palliative care, only a few empirical approaches to describe the sense of dignity from patients' and health care professionals' perspectives have been undertaken. However, individual descriptions of the dignity concept and definitions can serve as an impetus to improve the current palliative care practice by the development and evaluation of psychotherapeutic interventions for patients near the end of life and the allocation of resources. This article considers an internationally developed empirical-based model of dignity in severe and terminal ill patients by Chochinov et al. Furthermore, it illustrates the understanding of dignity as well as self-perceived exertions of influence on a patient's dignity from the perspective of health care professionals and volunteers. Psychotherapeutic interventions and strategies are introduced that can help conserve the sense of dignity of patients during palliative care.

Impacts of extreme heat on emergency medical service calls in King County, Washington, 2007-2012: relative risk and time series analyses of basic and advanced life support.

PubMed

Calkins, Miriam M; Isaksen, Tania Busch; Stubbs, Benjamin A; Yost, Michael G; Fenske, Richard A

2016-01-28

Exposure to excessive heat kills more people than any other weather-related phenomenon, aggravates chronic diseases, and causes direct heat illness. Strong associations between extreme heat and health have been identified through increased mortality and hospitalizations and there is growing evidence demonstrating increased emergency department visits and demand for emergency medical services (EMS). The purpose of this study is to build on an existing regional assessment of mortality and hospitalizations by analyzing EMS demand associated with extreme heat, using calls as a health metric, in King County, Washington (WA), for a 6-year period. Relative-risk and time series analyses were used to characterize the association between heat and EMS calls for May 1 through September 30 of each year for 2007-2012. Two EMS categories, basic life support (BLS) and advanced life support (ALS), were analyzed for the effects of heat on health outcomes and transportation volume, stratified by age. Extreme heat was model-derived as the 95th (29.7 °C) and 99th (36.7 °C) percentile of average county-wide maximum daily humidex for BLS and ALS calls respectively. Relative-risk analyses revealed an 8 % (95 % CI: 6-9 %) increase in BLS calls, and a 14 % (95 % CI: 9-20 %) increase in ALS calls, on a heat day (29.7 and 36.7 °C humidex, respectively) versus a non-heat day for all ages, all causes. Time series analyses found a 6.6 % increase in BLS calls, and a 3.8 % increase in ALS calls, per unit-humidex increase above the optimum threshold, 40.7 and 39.7 °C humidex respectively. Increases in "no" and "any" transportation were found in both relative risk and time series analyses. Analysis by age category identified significant results for all age groups, with the 15-44 and 45-64 year old age groups showing some of the highest and most frequent increases across health conditions. Multiple specific health conditions were associated with increased risk of an EMS call including abdominal/genito-urinary, alcohol/drug, anaphylaxis/allergy, cardiovascular, metabolic/endocrine, diabetes, neurological, heat illness and dehydration, and psychological conditions. Extreme heat increases the risk of EMS calls in King County, WA, with effects demonstrated in relatively younger populations and more health conditions than those identified in previous analyses.

Heat Death Associations with the built environment, social vulnerability and their interactions with rising temperature.

PubMed

Eisenman, David P; Wilhalme, Holly; Tseng, Chi-Hong; Chester, Mikhail; English, Paul; Pincetl, Stephanie; Fraser, Andrew; Vangala, Sitaram; Dhaliwal, Satvinder K

2016-09-01

In an extreme heat event, people can go to air-conditioned public facilities if residential air-conditioning is not available. Residences that heat slowly may also mitigate health effects, particularly in neighborhoods with social vulnerability. We explored the contributions of social vulnerability and these infrastructures to heat mortality in Maricopa County and whether these relationships are sensitive to temperature. Using Poisson regression modeling with heat-related mortality as the outcome, we assessed the interaction of increasing temperature with social vulnerability, access to publicly available air conditioned space, home air conditioning and the thermal properties of residences. As temperatures increase, mortality from heat-related illness increases less in census tracts with more publicly accessible cooled spaces. Mortality from all internal causes of death did not have this association. Building thermal protection was not associated with mortality. Social vulnerability was still associated with mortality after adjusting for the infrastructure variables. To reduce heat-related mortality, the use of public cooled spaces might be expanded to target the most vulnerable. Copyright © 2016 Elsevier Ltd. All rights reserved.

Endotoxin-associated protein: a potent stimulus for human granulocytopoietic activity which may be accessory cell independent.

PubMed Central

Bjornson, B H; Agura, E; Harvey, J M; Johns, M; Andrews, R G; McCabe, W R

1988-01-01

Proteins coextracted with endotoxin, termed endotoxin-associated protein (EAP), have been shown to exert interleukin 1-like activities. The present studies demonstrate that EAP also exerts potent granulopoietic colony-stimulating activity (CSA) on human peripheral blood and bone marrow progenitor cells, comparable to that seen with various types of conditioned media. The CSA observed with EAP appeared to be heat (100 degrees C, 30 min) and trypsin resistant and partially pronase resistant. Similar resistance was observed with the porin proteins of the outer membrane of gram-negative bacteria, and similar CSA activity was observed with a purified porin preparation of Neisseria gonorrhoeae. The CSA of EAP could be demonstrated in human peripheral blood and bone marrow leukocytes rigorously depleted of monocytes, T lymphocytes, and B lymphocytes by treatment with specific monoclonal antibodies and complement. PMID:2836311

[Sports and extreme conditions. Cardiovascular incidence in long term exertion and extreme temperatures (heat, cold)].

PubMed

Melin, B; Savourey, G

2001-06-30

During ultra-endurance exercise, both increase in body temperature and dehydration due to sweat losses, lead to a decrease in central blood volume. The heart rate drift allows maintaining appropriate cardiac output, in order to satisfy both muscle perfusion and heat transfer requirements by increasing skin blood flow. The resulting dehydration can impair thermal regulation and increase the risks of serious accidents as heat stroke. Endurance events, lasting more than 8 hours, result in large sweat sodium chloride losses. Thus, ingestion of large amounts of water with poor salt intake can induce symptomatic hyponatremia (plasma sodium < 130 mEq/L) which is also a serious accident. Heat environment increases the thermal constraint and when the air humidity is high, evaporation of sweat is compromise. Thus, thermal stress becomes uncompensable which increases the risk of cardiovascular collapse. Cold exposure induces physiological responses to maintain internal temperature by both limiting thermal losses and increasing metabolic heat production. Cold can induce accidental hypothermia and local frost-bites; moreover, it increases the risk of arrhythmia during exercise. Some guidelines (cardiovascular fitness, water and electrolyte intakes, protective clothing) are given for each extreme condition.

Tolazoline decreases survival time during microwave-induced lethal heat stress in anesthetized rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jauchem, J.R.; Chang, K.S.; Frei, M.R.

1996-03-01

Effects of {alpha}-adrenergic antagonists have been studied during environmental heating but not during microwave-induced heating. Tolazoline may exert some of its effects via {alpha}-adrenergic blockade. In the present study, ketamine-anesthetized Sprague-Dawley rats were exposed to 2450-MHz microwaves at an average power density of 60 mW/cm{sup 2} (whole-body specific absorption rate of approximately 14 W/kg) until lethal temperatures were attained. The effects of tolazoline (10 mg/kg body weight) on physiological responses (including changes in body temperature, heart rate, blood pressure, and respiratory rate) were examined. Survival time was significantly shorter in the tolazoline group than in saline-treated animals. In general, heartmore » rate and blood pressure responses were similar to those that occur during environmental heat stress. Heart rate, however, was significantly elevated in animals that received tolazoline, both before and during terminal microwave exposure. It is possible that changes associated with the elevated heart rate (e.g., less cardiac filling) in tolazoline-treated animals resulted in greater susceptibility to microwave-induced heating and the lower survival time. 47 refs., 3 figs., 2 tabs.« less

Heat stroke leading to acute liver injury & failure: A case series from the Acute Liver Failure Study Group.

PubMed

Davis, Brian C; Tillman, Holly; Chung, Raymond T; Stravitz, Richard T; Reddy, Rajender; Fontana, Robert J; McGuire, Brendan; Davern, Timothy; Lee, William M

2017-04-01

In the United States, nearly 1000 annual cases of heat stroke are reported but the frequency and outcome of severe liver injury in such patients is not well described. The aim of this study was to describe cases of acute liver injury (ALI) or failure (ALF) caused by heat stroke in a large ALF registry. Amongst 2675 consecutive subjects enrolled in a prospective observational cohort of patients with ALI or ALF between January 1998 and April 2015, there were eight subjects with heat stroke. Five patients had ALF and three had ALI. Seven patients developed acute kidney injury, all eight had lactic acidosis and rhabdomyolysis. Six patients underwent cooling treatments, three received N-acetyl cysteine (NAC), three required mechanical ventilation, three required renal replacement therapy, two received vasopressors, one underwent liver transplantation, and two patients died-both within 48 hours of presentation. All cases occurred between May and August, mainly in healthy young men because of excessive exertion. Management of ALI and ALF secondary to heat stroke should focus on cooling protocols and supportive care, with consideration of liver transplantation in refractory patients. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Long-term mortality experience of steelworkers. VIII. Mortality patterns of open hearth steelworkers (a preliminary report).

PubMed

Redmond, C K; Gustin, J; Kamon, E

1975-01-01

The findings in this report of a deficit in mortality from cardiovascular diseases and an excess in diseases of the digestive system among open hearth workers indicate the need for further study of men working in hot environments. In future reports we hope to refine the comparisons by obtaining data which will enable classification of workers more precisely by intensity and duration of exposure within the open hearth. Of particular importance in future work are the evaluation of possible relationships between the actual levels of heat exposure and subsequent morbidity and mortality, as well as possible interactions between heat stress and physical exertion in terms of the incidence of heart disease and other select diseases.

Thermal, physiological and perceptual strain mediate alterations in match-play tennis under heat stress.

PubMed

Périard, Julien D; Racinais, Sébastien; Knez, Wade L; Herrera, Christopher P; Christian, Ryan J; Girard, Olivier

2014-04-01

This study compared the thermal, physiological and perceptual responses associated with match-play tennis in HOT (∼34°C wet-bulb-globe temperature (WBGT)) and COOL (∼19°C WBGT) conditions, along with the accompanying alterations in match characteristics. 12 male tennis players undertook two matches for an effective playing time (ie, ball in play) of 20 min, corresponding to ∼119 and ∼102 min of play in HOT and COOL conditions, respectively. Rectal and skin temperatures, heart rate, subjective ratings of thermal comfort, thermal sensation and perceived exertion were recorded, along with match characteristics. End-match rectal temperature increased to a greater extent in the HOT (∼39.4°C) compared with the COOL (∼38.7°C) condition (p<0.05). Thigh skin temperature was higher throughout the HOT match (p<0.001). Heart rate, thermal comfort, thermal sensation and perceived exertion were also higher during the HOT match (p<0.001). Total playing time was longer in the HOT compared with the COOL match (p<0.05). Point duration (∼7.1 s) was similar between conditions, while the time between points was ∼10 s longer in the HOT relative to the COOL match (p<0.05). This led to a ∼3.4% lower effective playing percentage in the heat (p<0.05). Although several thermal, physiological and perceptual variables were individually correlated to the adjustments in time between points and effective playing percentage, thermal sensation was the only predictor variable associated with both adjustments (p<0.005). These adjustments in match-play tennis characteristics under severe heat stress appear to represent a behavioural strategy adopted to minimise or offset the sensation of environmental conditions being rated as difficult.

Using gait parameters to detect fatigue and responses to ice slurry during prolonged load carriage.

PubMed

Tay, Cheryl S; Lee, Jason K W; Teo, Ya S; Foo, Phildia Q Z; Tan, Pearl M S; Kong, Pui W

2016-01-01

This study examined (1) if changes in gait characteristics could indicate the exertional heat stress experienced during prolonged load carriage, and (2) if gait characteristics were responsive to a heat mitigation strategy. In an environmental chamber replicating tropical climatic conditions (ambient temperature 32°C, 70% relative humidity), 16 males aged 21.8 (1.2) years performed two trials of a work-rest cycle protocol consisting two bouts of 4-km treadmill walks with 30-kg load at 5.3km/h separated by a 15-min rest period. Ice slurry (ICE) or room temperature water (29°C) as a control (CON) was provided in 200-ml aliquots. The fluids were given 10min before the start, at the 15(th) and 30(th) min of each work cycle, and during each rest period. Spatio-temporal gait characteristics were obtained at the start and end of each work-rest cycle using a floor-based photocell system (OptoGait) and a high-speed video camera at 120Hz. Repeated-measure analysis of variance (trial×time) showed that with time, step width decreased (p=.024) while percent crossover steps increased (p=.008) from the 40(th) min onwards. Reduced stance time variability (-11.1%, p=.029) step width variability (-8.2%, p=.001), and percent crossover step (-18.5%, p=.010) were observed in ICE compared with CON. No differences in step length and most temporal variables were found. In conclusion, changes in frontal plane gait characteristics may indicate exertional heat stress during prolonged load carriage, and some of these changes may be mitigated with ice slurry ingestion. Copyright © 2015 Elsevier B.V. All rights reserved.

Heat exposure increases circulating fatty acids but not lipid oxidation at rest and during exercise.

PubMed

O'Hearn, Katharine; Tingelstad, Hans Christian; Blondin, Denis; Tang, Vera; Filion, Lionel G; Haman, François

2016-01-01

Alterations in lipid oxidation during exercise have been well studied, but limited data exists on the effects of passive heat exposure and exercise in the heat on changes in lipid oxidation. This study was designed to examine: (1) the effects of heat exposure on lipid metabolism during passive heating and subsequent exercise in the heat by focusing on changes in whole-body lipid oxidation and plasma lipid concentrations, and (2) the effects of extended passive pre-heating on exercise performance in the heat. Male participants (n=8) were passively heated for 120 min at 42 °C, then exercised on a treadmill in the same temperature at 50% V̇O2 max for 30 min (HEAT). This same procedure was followed on a separate occasion at 23 °C (CON). Results showed that lipid oxidation rates were not different between HEAT and CON during passive heating or exercise. However, non-esterified fatty acid (NEFA) concentrations were significantly higher following passive heating (618 µM, 95% CI: 479-757) compared to CON (391 µM, 95% CI: 270-511). The same trend was observed following exercise (2036 µM, 95% CI: 1604-2469 for HEAT and 1351 µM, 95% CI: 1002-1699). Triacylglycerol, phospholipid and cholesterol levels were not different between HEAT and CON at any point. Four of 8 participants could not complete 30 min of exercise in HEAT, resulting in a 14% decline in total external work. Rate of perceived exertion over the final 5 min of exercise was higher in HEAT (9.5) than CON (5). We conclude that: (1) heat exposure results in increased circulating NEFA at rest and during exercise without changes in whole-body lipid utilization, and (2) passive pre-heating reduces work capacity during exercise in the heat and increases the perceived intensity of a given workload. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Effect of Intermittent Vest Cooling on Thermoregulation and Cardiovascular Strain in Baseball Catchers.

PubMed

Bishop, Stacy H; Szymanski, David J; Ryan, Greg A; Herron, Robert L; Bishop, Phil A

2017-08-01

Bishop, SH, Szymanski, DJ, Ryan, GA, Herron, RL, and Bishop, PA. The effect of intermittent vest cooling on thermoregulation and cardiovascular strain in baseball catchers. J Strength Cond Res 31(8): 2060-2065, 2017-Baseball catchers are exposed to multiple physiological challenges while playing outside during the spring and summer months, many of which deal with recovery and thermoregulation. The purpose of this study was to investigate the effect of intermittent cooling on core temperature, cardiovascular strain, exertion, and recovery during a simulated catching performance in the heat. Six trained college-aged baseball catchers performed in a controlled, hot (35° C), and humid (25% relative humidity) environment in a counter-balanced, cross-over design. Ice vest cooling (VC) was used as a cooling modality and was compared with a control of no cooling (NC). Rectal temperature (Tre), heart rate (HR), rating of perceived exertion (RPE), and perceived recovery scale (PRS) were recorded before and after each simulated inning. All activities took place in a heat chamber, and each inning consisted of catchers receiving 12 pitches in their position followed by 6 minutes of recovery. Nine total innings were performed, and 27 total innings were performed with each of the 2 treatments. A significantly smaller mean Tre change was seen in VC when compared with NC (0.58 ± 0.2° C, 0.98 ± 0.2° C, p ≤ 0.01, respectively). Rating of perceived exertion was significantly lower and PRS was significantly improved for VC compared with NC (both p ≤ 0.05). Mean recovery HR during VC was significantly lower than NC in the fifth (VC = 84 ± 8 b·min, NC = 90 ± 9 b·min, p = 0.04), seventh (VC = 84 ± 3 b·min, NC = 92 ± 7 b·min, p = 0.02), and ninth (VC = 85 ± 7 b·min, NC = 93 ± 5 b·min, p = 0.01) innings. Heart rate during catching was significantly lower at the end of the VC trials when compared with NC (108 ± 16 b·min vs. 120 ± 19 b·min, p = 0.02, respectively). Vest cooling decreased heat strain, cardiovascular strain, and RPE while it improved perceived recovery in catchers over a simulated 3-game series performed in hot conditions.

Composite Study Of Aerosol Long-Range Transport Events From East Asia And North America

NASA Astrophysics Data System (ADS)

Jiang, X.; Waliser, D. E.; Guan, B.; Xavier, P.; Petch, J.; Klingaman, N. P.; Woolnough, S.

2011-12-01

While the Madden-Julian Oscillation (MJO) exerts pronounced influences on global climate and weather systems, current general circulation models (GCMs) exhibit rather limited capability in representing this prominent tropical variability mode. Meanwhile, the fundamental physics of the MJO are still elusive. Given the central role of the diabatic heating for prevailing MJO theories and demands for reducing the model deficiencies in simulating the MJO, a global model inter-comparison project on diabatic processes and vertical heating structure associated with the MJO has been coordinated through a joint effort by the WCRP-WWRP/THORPEX YOTC MJO Task Force and GEWEX GASS Program. In this presentation, progress of this model inter-comparison project will be reported, with main focus on climate simulations from about 27 atmosphere-only and coupled GCMs. Vertical structures of heating and diabatic processes associated with the MJO based on multi-model simulations will be presented along with their reanalysis and satellite estimate counterparts. Key processes possibly responsible for a realistic simulation of the MJO, including moisture-convection interaction, gross moist stability, ocean coupling, and surface heat flux, will be discussed.

Risk Factors for Heat-Related Illness in Washington Crop Workers.

PubMed

Spector, June T; Krenz, Jennifer; Blank, Kristina N

2015-01-01

Crop workers are at high risk of heat-related illness (HRI) from internal heat generated by heavy physical work, particularly when laboring in hot and humid conditions. The aim of this study was to identify risk factors for HRI symptoms in Washington crop workers using an audio computer-assisted self-interview (A-CASI) instrument that has undergone reliability and validity evaluation. A cross-sectional A-CASI survey of 97 crop workers in Washington State was conducted during the summer of 2013. Potential HRI risk factors in demographic, training, work, hydration, clothing, health, and environmental domains were selected a priori for evaluation. Mixed-effects logistic regression was used to identify risk factors for self-reported symptoms associated with heat strain and HRI (dizziness/light-headedness or heavy sweating) experienced at work in hot conditions. An increase in age was associated with a lower odds of HRI symptoms (odds ratio [OR] = 0.92; 95% confidence interval [CI] = 0.87-0.98). Piece rate compared with hourly payment (OR = 6.20; 95% CI = 1.11-34.54) and needing to walk for more than 3 minutes to get to the toilet, compared with less than 3 minutes (OR = 4.86; 95% CI = 1.18-20.06), were associated with a higher odds of HRI symptoms. In this descriptive study of risk factors for HRI symptoms in Washington crop workers, decreased age (and less work experience), piece rate pay, and longer distance to the toilet were associated with self-reported HRI symptoms. Modifiable workplace factors should be considered in HRI prevention efforts that are evaluated using objective measures in representative working populations.

The physiological demands of horseback mustering when wearing an equestrian helmet.

PubMed

Taylor, Nigel A S; Caldwell, Joanne N; Dyer, Rodd

2008-09-01

The hottest months on northern Australian cattle stations are from September to November, and it is during these months that horseback cattle mustering occurs. Stockmen wear clothing that restricts heat loss, and protective helmets have recently been introduced. Anecdotal evidence points to the possibility that helmets may increase the probability of developing heat illness, or reducing workplace performance. In this project, we quantified the working (thermal) environment on such cattle stations, and measured the metabolic demands on, and concurrent physiological strain in stockmen during mustering, whilst wearing an equestrian helmet. During horseback work, the average heart rate was 102.0 beats min(-1) (SD 14.0), with almost 90% of the time (238 min) spent working at intensities <50% of the heart rate reserve. The projected metabolic heat production during mustering ranged between 178 and 333 W (women), and between 212 and 542 W (men). The average core temperature was 37.6 degrees C, while the mean skin temperature averaged 34.1 degrees C. It was concluded that the working environment is, on average, thermally uncompensable during the mustering season. However, horseback mustering per se is a relatively low-intensity activity, interspersed with short periods of high-intensity work. This activity level was reflected within core temperatures, which rarely climbed above values associated with light-moderate exercise. Thus, whilst the climatic state was uncompensable, stockmen used behavioural strategies to minimise the risk of heat illness. Finally, it was observed that the helmet, though unpleasant to wear, did not appear to increase thermal strain in a manner that would disadvantage stockmen.

Mechanisms of Autonomic Dysfunction Associated with Extreme Exertional Heat Stroke and Potential Efficacy of Novel Pharmacological Treatments

DTIC Science & Technology

2014-12-01

cardiovascular diseases. At higher doses, these medications have been prescribed to treat high blood pressure in humans and both may have relevance as...HR, and Tc. § Low frequency (LF) systolic blood pressure variability as an index of sympathetic modulation of vascular tone. § LF and high ... blood pressure variability (LFSYS), LF heart rate variability (LFHR), and high frequency heart rate variability (HFHR) in placebo-, clonidine-, and

The Impact of Heat Exposure and Sleep Restriction on Firefighters’ Work Performance and Physiology during Simulated Wildfire Suppression

PubMed Central

Vincent, Grace E.; Aisbett, Brad; Larsen, Brianna; Ridgers, Nicola D.; Snow, Rod; Ferguson, Sally A.

2017-01-01

This study was designed to examine the effects of ambient heat on firefighters’ physical task performance, and physiological and perceptual responses when sleep restricted during simulated wildfire conditions. Thirty firefighters were randomly allocated to the sleep restricted (n = 17, SR; 19 °C, 4-h sleep opportunity) or hot and sleep restricted (n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Firefighters performed two days of simulated, intermittent, self-paced work circuits comprising six firefighting tasks. Heart rate, and core temperature were measured continuously. After each task, firefighters reported their rating of perceived exertion and thermal sensation. Effort sensation was also reported after each work circuit. Fluids were consumed ad libitum. Urine volume and urine specific gravity were analysed. Sleep was monitored using polysomnography. There were no differences between the SR and HOT + SR groups in firefighters’ physiological responses, hydration status, ratings of perceived exertion, motivation, and four of the six firefighting tasks (charged hose advance, rake, hose rolling, static hose hold). Black out hose and lateral repositioning were adversely affected in the HOT + SR group. Working in hot conditions did not appear to consistently impair firefighters work performance, physiology, and perceptual responses. Future research should determine whether such findings remain true when individual tasks are performed over longer durations. PMID:28208688

Chronic fatigue syndrome (CFS) symptom-based phenotypes in two clinical cohorts of adult patients in the UK and The Netherlands.

PubMed

Collin, Simon M; Nikolaus, Stephanie; Heron, Jon; Knoop, Hans; White, Peter D; Crawley, Esther

2016-02-01

Studies have provided evidence of heterogeneity within chronic fatigue syndrome (CFS), but few have used data from large cohorts of CFS patients or replication samples. 29 UK secondary-care CFS services recorded the presence/absence of 12 CFS-related symptoms; 8 of these symptoms were recorded by a Dutch tertiary service. Latent Class Analysis (LCA) was used to assign symptom profiles (phenotypes). Regression models were fitted with phenotype as outcome (in relation to age, sex, BMI, duration of illness) and exposure (in relation to comorbidities and patient-reported measures). Data were available for 7041 UK and 1392 Dutch patients. Almost all patients in both cohorts presented with post-exertional malaise, cognitive dysfunction and disturbed/unrefreshing sleep, and these 3 symptoms were excluded from LCA. In UK patients, six phenotypes emerged: 'full' polysymptomatic (median 8, IQR 7-9 symptoms) 32.8%; 'pain-only' (muscle/joint) 20.3%; 'sore throat/painful lymph node' 4.5%; and 'oligosymptomatic' (median 1, IQR 0-2 symptoms) 4.7%. Two 'partial' polysymptomatic phenotypes were similar to the 'full' phenotype, bar absence of dizziness/nausea/palpitations (21.4%) or sore throat/painful lymph nodes (16.3%). Women and patients with longer duration of illness were more likely to be polysymptomatic. Polysymptomatic patients had more severe illness and more comorbidities. LCA restricted to 5 symptoms recorded in both cohorts indicated 3 classes (polysymptomatic, oligosymptomatic, pain-only), which were replicated in Dutch data. Adults with CFS may have one of 6 symptom-based phenotypes associated with sex, duration and severity of illness, and comorbidity. Future research needs to determine whether phenotypes predict treatment outcomes, and require different treatments. Copyright © 2015 Elsevier Inc. All rights reserved.

Attitudes towards euthanasia in severely ill and dementia patients and cremation in Cyprus: a population-based survey

PubMed Central

2013-01-01

Background Population studies on end-of-life decisions have not been conducted in Cyprus. Our study aim was to evaluate the beliefs and attitudes of Greek Cypriots towards end-of-life issues regarding euthanasia and cremation. Methods A population-based telephone survey was conducted in Cyprus. One thousand randomly selected individuals from the population of Cyprus age 20 years or older were invited to participate. Beliefs and attitudes on end-of-life decisions were collected using an anonymous and validated questionnaire. Statistical analyses included cross-tabulations, Pearson’s chi-square tests and multivariable-adjusted logistic regression models. Results A total of 308 males and 689 females participated in the survey. About 70% of the respondents did not support euthanasia for people with incurable illness and/or elders with dementia when requested by them and 77% did not support euthanasia for people with incurable illness and/or elders with dementia when requested by relatives. Regarding cremation, 78% were against and only 14% reported being in favor. Further statistical analyses showed that male gender, being single and having reached higher educational level were factors positively associated with support for euthanasia in a statistically significant fashion. On the contrary, the more religiosity expressed by study participants, the less support they reported for euthanasia or cremation. Conclusions The vast majority of Greek Cypriots does not support euthanasia for people with incurable illness and/or elders with dementia and also do not support cremation. Certain demographic characteristics such as age and education have a positive influence towards attitudes for euthanasia and cremation, while religiosity exerts a strong negative influence on the above. Family bonding as well as social and cultural traditions may also play a role although not comprehensively evaluated in the current study. PMID:24060291

Attitudes towards euthanasia in severely ill and dementia patients and cremation in Cyprus: a population-based survey.

PubMed

Televantos, Anastasios; Talias, Michael A; Charalambous, Marianna; Soteriades, Elpidoforos S

2013-09-23

Population studies on end-of-life decisions have not been conducted in Cyprus. Our study aim was to evaluate the beliefs and attitudes of Greek Cypriots towards end-of-life issues regarding euthanasia and cremation. A population-based telephone survey was conducted in Cyprus. One thousand randomly selected individuals from the population of Cyprus age 20 years or older were invited to participate. Beliefs and attitudes on end-of-life decisions were collected using an anonymous and validated questionnaire. Statistical analyses included cross-tabulations, Pearson's chi-square tests and multivariable-adjusted logistic regression models. A total of 308 males and 689 females participated in the survey. About 70% of the respondents did not support euthanasia for people with incurable illness and/or elders with dementia when requested by them and 77% did not support euthanasia for people with incurable illness and/or elders with dementia when requested by relatives. Regarding cremation, 78% were against and only 14% reported being in favor. Further statistical analyses showed that male gender, being single and having reached higher educational level were factors positively associated with support for euthanasia in a statistically significant fashion. On the contrary, the more religiosity expressed by study participants, the less support they reported for euthanasia or cremation. The vast majority of Greek Cypriots does not support euthanasia for people with incurable illness and/or elders with dementia and also do not support cremation. Certain demographic characteristics such as age and education have a positive influence towards attitudes for euthanasia and cremation, while religiosity exerts a strong negative influence on the above. Family bonding as well as social and cultural traditions may also play a role although not comprehensively evaluated in the current study.

Heat waves and their significance for a temperate benthic community: A near-natural experimental approach.

PubMed

Pansch, Christian; Scotti, Marco; Barboza, Francisco R; Al-Janabi, Balsam; Brakel, Janina; Briski, Elizabeta; Bucholz, Björn; Franz, Markus; Ito, Maysa; Paiva, Filipa; Saha, Mahasweta; Sawall, Yvonne; Weinberger, Florian; Wahl, Martin

2018-04-23

Climate change will not only shift environmental means but will also increase the intensity of extreme events, exerting additional stress on ecosystems. While field observations on the ecological consequences of heat waves are emerging, experimental evidence is rare, and lacking at the community level. Using a novel "near-natural" outdoor mesocosms approach, this study tested whether marine summer heat waves have detrimental consequences for macrofauna of a temperate coastal community, and whether sequential heat waves provoke an increase or decrease of sensitivity to thermal stress. Three treatments were applied, defined and characterized through a statistical analysis of 15 years of temperature records from the experimental site: (1) no heat wave, (2) two heat waves in June and July followed by a summer heat wave in August and (3) the summer heat wave only. Overall, 50% of the species showed positive, negative or positive/negative responses in either abundance and/or biomass. We highlight four possible ways in which single species responded to either three subsequent heat waves or one summer heat wave: (1) absence of a response (tolerance, 50% of species), (2) negative accumulative effects by three subsequent heat waves (tellinid bivalve), (3) buffering by proceeding heat waves due to acclimation and/or shifts in phenology (spionid polychaete) and (4) an accumulative positive effect by subsequent heat waves (amphipod). The differential responses to single or sequential heat waves at the species level entailed shifts at the community level. Community-level differences between single and triple heat waves were more pronounced than those between regimes with vs. without heat waves. Detritivory was reduced by the single heat wave while suspension feeding was less common in the triple heat wave regime. Critical extreme events occur already today and will occur more frequently in a changing climate, thus, leading to detrimental impacts on coastal marine systems. © 2018 John Wiley & Sons Ltd.

Outpatient clinic visits during heat waves: findings from a large family medicine clinical database.

PubMed

Vashishtha, Devesh; Sieber, William; Hailey, Brittany; Guirguis, Kristen; Gershunov, Alexander; Al-Delaimy, Wael K

2018-03-10

The purpose of this study was to determine whether heat waves are associated with increased frequency of clinic visits for ICD-9 codes of illnesses traditionally associated with heat waves. During 4 years of family medicine clinic data between 2012 and 2016, we identified six heat wave events in San Diego County. For each heat wave event, we selected a control period in the same season that was twice as long. Scheduling a visit on a heat wave day (versus a non-heat wave day) was the primary predictor, and receiving a primary ICD-9 disease code related to heat waves was the outcome. Analyses were adjusted for age, gender, race/ethnicity and marital status. Of the 5448 visits across the heat wave and control periods, 6.4% of visits (n = 346) were for heat wave-related diagnoses. Scheduling a visit on heat wave day was not associated with receiving a heat wave-related ICD code as compared with the control period (adjusted odds ratio: 1.35; 95% confidence interval: 0.86-1.36; P = 0.51). We show that in a relatively large and demographically diverse population, patients who schedule appointments during heat waves are not being more frequently seen for diagnoses typically associated with heat waves in the acute setting. Given that heat waves are increasing in frequency due to climate change, there is an opportunity to increase utilization of primary care clinics during heat waves.

Hypertensive Crisis During Norepinephrine Syringe Exchange: A Case Report.

PubMed

Snijder, Roland A; Knape, Johannes T A; Egberts, Toine C G; Timmerman, Annemoon M D E

2017-04-01

A 67-year critically ill patient suffered from a hypertensive crisis (200 mm Hg) because of a norepinephrine overdose. The overdose occurred when the clinician exchanged an almost-empty syringe and the syringe pump repeatedly reported an error. We hypothesized that an object between the plunger and the syringe driver may have caused the exertion of too much force on the syringe. Testing this hypothesis in vitro showed significant peak dosing errors (up to +572%) but moderate overdose (0.07 mL, +225%) if a clamp was used on the intravenous infusion line and a large overdose (0.8 mL, +2700%) if no clamp was used. Clamping and awareness are advised.

Sickle cell trait: what are the costs and benefits of screening?

PubMed

Shephard, Roy J

2016-12-01

Eight percent of African Americans are carriers of the sickle cell trait. Some regard this as a benign anomaly, but others point to incidents of sudden exercise-related death, calling for a preliminary screening of either all athletes or those of African-American ancestry. This brief review considers the costs and benefits of such screening. The Ovid/Health Star data-base was searched from 1996 to June 2015. 2014. The terms "exercise", "exercise therapy", "sports", "athletes", "physical activity/motor activity" and "physical fitness" were combined to yield 227,120 citations. Likewise, the terms "sickle cell trait", "sickle cell disease", "splenic infarction", "hemoglobin S" and "rhabdomyolysis" identified 12,325 citations. A combination of the 2 searches yielded 416 abstracts. Excluding items relating to animal research or forms of rhabdomyolysis other than sickling left 375 abstracts; 115 papers merited full examination. This material covered the risks of sickle cell trait and of screening (55 items), effects upon physical performance (31 items), cellular mechanisms (23 items), nutrition (4 items), and other topics (2 items). Supplemented material was drawn from reference lists and personal files. The tendency to sickling was provoked by excessive exercise relative to physical condition in hot or hypoxic conditions, and by local tissue acidosis, conditions that were best avoided by all athletes. The condition had little impact upon physical performance, but the relative risks of heat illness, exertional rhabdomyolysis, splenic infarction and sudden death were all increased by the sickle cell trait. The absolute number of critical incidents was nevertheless small, calling for close assessment of the costs and putative benefits of widespread screening. Sports physicians should be aware of the clinical picture of sickling and be prepared to treat it. Screening may be cost-effective if targeted to black athletes involved in certain sports, although it has yet to be demonstrated how far the diagnosis of sickle cell trait reduces the risk of death when exercising in an adverse environment. A better tactic may be to reduce risks for all competitors by educating athletes and their coaches to adopt an intensity of training appropriate to the individual's physical condition, to maintain full hydration, and to avoid exposure to excessive heat and hypoxia.

PDO modulation of the ENSO impact on the summer South Asian high

NASA Astrophysics Data System (ADS)

Xue, Xu; Chen, Wen; Chen, Shangfeng; Feng, Juan

2018-02-01

This study investigates modulation effects of the Pacific decadal oscillation (PDO) on the impact of boreal winter El Niño-Southern Oscillation (ENSO) on the South Asian high (SAH) variability in the following summer. In the El Niño together with positive PDO (EL/+PDO) or the La Niña together with negative PDO (LA/-PDO) years, boreal winter ENSO can influence the following summer SAH activity significantly. The SAH tends to be obviously strengthened (weakened) and located further south (north) during EL/+PDO (LA/-PDO). However, in the El Niño together with negative PDO (EL/-PDO) or the La Niña together with positive PDO (LA/+PDO) years, the influence of ENSO on the SAH tends to be weak. The strength and location of SAH are close to those in the climatology of 1950-2011 during the EL/-PDO or the LA/+PDO. Further analysis indicates that the PDO could exert pronounced influence on the ENSO-SAH connection via modulating the anomalous Walker circulation and charge effect over the tropical Indian Ocean (TIO). During the EL/+PDO or LA/-PDO, the anomalous Walker circulation associated with El Niño or La Niña is stronger and lasts for a longer time than those during the EL/-PDO or LA/+PDO. This leads to stronger descending (ascending) motion over the Maritime Continent and easterly (westerly) wind anomalies over the eastern Indian Ocean in the EL/+PDO (LA/-PDO), which further exert larger effects on the surface heat fluxes and subsurface ocean dynamical heating process over the Indian Ocean. As such, the induced warm (cold) sea surface temperature anomalies over the Indian Ocean are more significant and larger in the EL/+PDO (LA/-PDO). These larger sea surface temperature anomalies over the TIO could exert a more significant influence on the tropospheric temperature via moisture adjustment, which subsequently results in stronger SAH variability in the EL/+PDO or the LA/-PDO.

Use of thermal imagery for estimation of core body temperature during precooling, exertion, and recovery in wildland firefighter protective clothing.

PubMed

Bourlai, Thirimachos; Pryor, Riana R; Suyama, Joe; Reis, Steven E; Hostler, David

2012-01-01

Monitoring core body temperature to identify heat stress in first responders and in individuals participating in mass gatherings (e.g., marathons) is difficult. This study utilized high-sensitivity thermal imaging technology to predict the core temperature of human subjects at a distance while performing simulated field operations wearing thermal protective garments. Six male subjects participating in a study of precooling prior to exertion in wildland firefighter thermal protective clothing had thermal images of the face captured with a high-resolution thermal imaging camera concomitant with measures of core and skin temperature before, during, and after treadmill exercise in a heated room. Correlations and measures of agreement between core temperature and thermal imaging-based temperature were performed. The subjects walked an average (± standard deviation) of 42.6 (±5.9) minutes and a distance of 4.2 (±0.6) km on the treadmill. Mean heart rate at the end of exercise was 152 (±33) bpm and core body temperature at the end of exercise was 38.3°C (±0.7°C). A visual relationship and a strong correlation between core temperature and thermal imaging of the face were identified in all subjects, with the closest relationship and best agreement occurring during exercise. The Bland-Altman test of agreement during exercise revealed the majority of measurement pairs to be within two standard deviations of the measured temperature. High-resolution thermal imaging in the middle-wave infrared spectrum (3-5 μm) can be used to accurately estimate core body temperature during exertion in a hot room while participants are wearing wildland firefighting garments. Although this technology is promising, it must be refined. Using alternative measurement sites such as the skin over the carotid artery, using multiple measurement sites, or adding pulse detection may improve the estimation of body temperature by thermal imagery.

Ice cooling vest on tolerance for exercise under uncompensable heat stress.

PubMed

Kenny, Glen P; Schissler, Andrew R; Stapleton, Jill; Piamonte, Matthew; Binder, Konrad; Lynn, Aaron; Lan, Christopher Q; Hardcastle, Stephen G

2011-08-01

This study was conducted to evaluate the effectiveness of a commercial, personal ice cooling vest on tolerance for exercise in hot (35°C), wet (65% relative humidity) conditions with a nuclear biological chemical suit (NBC). On three separate occasions, 10 male volunteers walked on a treadmill at 3 miles per hour and 2% incline while (a) seminude (denoted CON), (b) dressed with a nuclear, biological, chemical (NBC) suit with an ice vest (V) worn under the suit (denoted NBCwV); or (c) dressed with an NBC suit but without an ice vest (V) (denoted NBCwoV). Participants exercised for 120 min or until volitional fatigue, or esophageal temperature reached 39.5°C. Esophageal temperature (T(es)), heart rate (HR), thermal sensation, and ratings of perceived exertion were measured. Exercise time was significantly greater in CON compared with both NBCwoV and NBCwV (p < 0.05), whereas T(es), thermal sensation, heart rate, and rate of perceived exertion were lower (p < 0.05). Wearing the ice vest increased exercise time (NBCwoV, 103.6 ± 7.0 min; NBCwV, 115.9 ± 4.1 min) and reduced the level of thermal strain, as evidenced by a lower T(es) at end-exercise (NBCwoV, 39.03 ± 0.13°C; NBCwV, 38.74 ± 0.13°C) and reduced thermal sensation (NBCwoV, 6.4 ± 0.4; NBCwV, 4.8 ± 0.6). This was paralleled by a decrease in rate of perceived exertion (NBCwoV, 14.7 ± 1.6; NBCwV, 12.4 ± 1.6) (p < 0.05) and heat rate (NBCwoV, 169 ± 6; NBCwV, 159 ± 7) (p < 0.05). We show that a commercially available cooling vest can significantly reduce the level of thermal strain during work performed in hot environments.

Dopamine D2/D3 but not dopamine D1 receptors are involved in the rapid antidepressant-like effects of ketamine in the forced swim test.

PubMed

Li, Yan; Zhu, Zhuo R; Ou, Bao C; Wang, Ya Q; Tan, Zhou B; Deng, Chang M; Gao, Yi Y; Tang, Ming; So, Ji H; Mu, Yang L; Zhang, Lan Q

2015-02-15

Major depressive disorder is one of the most prevalent and life-threatening forms of mental illnesses. The traditional antidepressants often take several weeks, even months, to obtain clinical effects. However, recent clinical studies have shown that ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, exerts rapid antidepressant effects within 2h and are long-lasting. The aim of the present study was to investigate whether dopaminergic system was involved in the rapid antidepressant effects of ketamine. The acute administration of ketamine (20 mg/kg) significantly reduced the immobility time in the forced swim test. MK-801 (0.1 mg/kg), the more selective NMDA antagonist, also exerted rapid antidepressant-like effects. In contrast, fluoxetine (10 mg/kg) did not significantly reduced the immobility time in the forced swim test after 30 min administration. Notably, pretreatment with haloperidol (0.15 mg/kg, a nonselective dopamine D2/D3 antagonist), but not SCH23390 (0.04 and 0.1 mg/kg, a selective dopamine D1 receptor antagonist), significantly prevented the effects of ketamine or MK-801. Moreover, the administration of sub-effective dose of ketamine (10 mg/kg) in combination with pramipexole (0.3 mg/kg, a dopamine D2/D3 receptor agonist) exerted antidepressant-like effects compared with each drug alone. In conclusion, our results indicated that the dopamine D2/D3 receptors, but not D1 receptors, are involved in the rapid antidepressant-like effects of ketamine. Copyright © 2014 Elsevier B.V. All rights reserved.

Dopamine antagonism decreases willingness to expend physical, but not cognitive, effort: a comparison of two rodent cost/benefit decision-making tasks.

PubMed

Hosking, Jay G; Floresco, Stan B; Winstanley, Catharine A

2015-03-01

Successful decision making often requires weighing a given option's costs against its associated benefits, an ability that appears perturbed in virtually every severe mental illness. Animal models of such cost/benefit decision making overwhelmingly implicate mesolimbic dopamine in our willingness to exert effort for a larger reward. Until recently, however, animal models have invariably manipulated the degree of physical effort, whereas human studies of effort have primarily relied on cognitive costs. Dopamine's relationship to cognitive effort has not been directly examined, nor has the relationship between individuals' willingness to expend mental versus physical effort. It is therefore unclear whether willingness to work hard in one domain corresponds to willingness in the other. Here we utilize a rat cognitive effort task (rCET), wherein animals can choose to allocate greater visuospatial attention for a greater reward, and a previously established physical effort-discounting task (EDT) to examine dopaminergic and noradrenergic contributions to effort. The dopamine antagonists eticlopride and SCH23390 each decreased willingness to exert physical effort on the EDT; these drugs had no effect on willingness to exert mental effort for the rCET. Preference for the high effort option correlated across the two tasks, although this effect was transient. These results suggest that dopamine is only minimally involved in cost/benefit decision making with cognitive effort costs. The constructs of mental and physical effort may therefore comprise overlapping, but distinct, circuitry, and therapeutic interventions that prove efficacious in one effort domain may not be beneficial in another.

Linking potential heat source and sink to urban heat island: Heterogeneous effects of landscape pattern on land surface temperature.

PubMed

Li, Weifeng; Cao, Qiwen; Lang, Kun; Wu, Jiansheng

2017-05-15

Rapid urbanization has significantly contributed to the development of urban heat island (UHI). Regulating landscape composition and configuration would help mitigate the UHI in megacities. Taking Shenzhen, China, as a case study area, we defined heat source and heat sink and identified strong and weak sources as well as strong and weak sinks according to the natural and socioeconomic factors influencing land surface temperature (LST). Thus, the potential thermal contributions of heat source and heat sink patches were differentiated. Then, the heterogeneous effects of landscape pattern on LST were examined by using semiparametric geographically weighted regression (SGWR) models. The results showed that landscape composition has more significant effects on thermal environment than configuration. For a strong source, the percentage of patches has a positive impact on LST. Additionally, when mosaicked with some heat sink, even a small improvement in the degree of dispersion of a strong source helps to alleviate UHI. For a weak source, the percentage and density of patches have positive impacts on LST. For a strong sink, the percentage, density, and degree of aggregation of patches have negative impacts on LST. The effects of edge density and patch shape complexity vary spatially with the fragmentation of a strong sink. Similarly, the impacts of a weak sink are mainly exerted via the characteristics of percent, density, and shape complexity of patches. Copyright © 2017 Elsevier B.V. All rights reserved.

Lipoic Acid Exerts Antioxidant and Anti-inflammatory Effects in Response to Heat Shock in C2C12 Myotubes.

PubMed

Lee, Cheng-Tse; Chang, Li-Ching; Wu, Pei-Fung

2016-06-01

This study explored that lipoic acid treatment for 24 h significantly upregulated and promoted heat shock-induced catalase expression and downregulated GPx1 messenger RNA (mRNA) expression, indicating that lipoic acid exhibits antioxidant activity in the decomposition of hydrogen peroxide by upregulating catalase expression. Moreover, lipoic acid treatment for 3 h increased and promoted heat shock-induced interleukin (IL)-6 mRNA and protein levels and that for 24 h downregulated IL-6 mRNA expression, suggesting a dual effect of lipoic acid on IL-6 regulation. Lipoic acid alone failed to increase or reduce tumor necrosis factor (TNF)-α mRNA and protein levels, whereas heat shock alone downregulated TNF-α mRNA and protein expression. These data suggest that lipoic acid does not have a proinflammatory role and that heat shock acts as an anti-inflammatory agent by downregulating TNF-α expression in C2C12 myotubes. Moreover, lipoic acid or heat shock alone upregulated the IL-6 receptor (IL-6R-α) and glycoprotein 130 (gp130) mRNA expression followed by IL-6 expression; these data indicate that the regulation of lipoic acid or heat shock is mediated by IL-6R signaling, thus suggesting that C2C12 myotubes possesses a mechanism for regulating IL-6R and gp130 expression following lipoic acid treatment or heat shock.

Controversy in the Psychology Classroom: Using Hot Topics to Foster Critical Thinking

ERIC Educational Resources Information Center

Dunn, Dana S., Ed.; Gurung, Regan A. R., Ed.; Naufel, Karen Z., Ed.; Wilson, Janie H., Ed.

2012-01-01

One of the hallmarks of a quality liberal arts education is providing undergraduates the opportunity to wrestle with controversial issues. Yet many teachers feel ill-equipped when it comes to broaching disagreeable topics, managing the resulting heated debates, or helping students to separate their personal feelings from scientific evidence. This…

Pasteurization of shell eggs using radio frequency heating

USDA-ARS?s Scientific Manuscript database

The USDA-FSIS estimates that pasteurization of all shell eggs in the U.S. would reduce the annual number of illnesses by more than 110,000, yet less than 1% of shell eggs are commercially pasteurized. One of the main reasons for this is that the current process, hot water immersion, requires approxi...

Collecting and banking human milk: to heat or not to heat?

PubMed

Björkstén, B; Burman, L G; De Château, P; Fredrikzon, B; Gothefors, L; Hernell, O

1980-09-20

Data on human breast milk and its handling when fed to babies who cannot be breast-fed were reviewed to determine whether the method of processing and storage affected the properties of the milk. Breast milk is normally contaminated by potential pathogens, which seem to produce no ill effects, but it also contains antimicrobial properties which protect against infection. The evidence suggests that pasteurisation not only eliminates pathogenic bacteria but also damages bacteriostatic mechanisms, so making the milk more susceptible to later contamination. Pasteurisation also affects the nutritional properties of milk. Freezing has little effect on milk proteins, while a study on the effect of refrigeration showed that there was little bacterial growth at temperatures below 8 degrees C. Several years' experience of feeding donated raw milk to newborn infants has confirmed that it produces no ill effects. These findings suggest that pasteurisation of donated breastmilk is unnecessary, and it is not recommended, while the decision whether or not to freeze the milk may be made on practical grounds. Raw breast milk can be safely stored at 4-6 degrees C for 72 hours.

Glutamine Randomized Studies in Early Life: The Unsolved Riddle of Experimental and Clinical Studies

PubMed Central

Briassouli, Efrossini; Briassoulis, George

2012-01-01

Glutamine may have benefits during immaturity or critical illness in early life but its effects on outcome end hardpoints are controversial. Our aim was to review randomized studies on glutamine supplementation in pups, infants, and children examining whether glutamine affects outcome. Experimental work has proposed various mechanisms of glutamine action but none of the randomized studies in early life showed any effect on mortality and only a few showed some effect on inflammatory response, organ function, and a trend for infection control. Although apparently safe in animal models (pups), premature infants, and critically ill children, glutamine supplementation does not reduce mortality or late onset sepsis, and its routine use cannot be recommended in these sensitive populations. Large prospectively stratified trials are needed to better define the crucial interrelations of “glutamine-heat shock proteins-stress response” in critical illness and to identify the specific subgroups of premature neonates and critically ill infants or children who may have a greater need for glutamine and who may eventually benefit from its supplementation. The methodological problems noted in the reviewed randomized experimental and clinical trials should be seriously considered in any future well-designed large blinded randomized controlled trial involving glutamine supplementation in critical illness. PMID:23019424

Negative Illness Perceptions are Associated with a Pro-nociceptive Modulation Profile and Augmented Pelvic Pain.

PubMed

Grinberg, Keren; Granot, Michal; Lowenstein, Lior; Abramov, Liora; Weissman-Fogel, Irit

2018-05-25

A patient's personal interpretations of a health threat or "illness perceptions" (IPs) are associated with their clinical outcomes. This study explored whether IPs are associated with pain severity and ability to modulate pain in women with chronic pelvic pain syndrome (CPPS), as well as the predictive value of IPs on Myofascial Physical Therapy (MPT) success. Illness Perceptions Questionnaire - Revised (IPQ-R), mechanical and heat pain thresholds, mechanical temporal summation (mTS), and conditioned pain modulation (CPM) were evaluated in CPPS patients (n=39) before, and 3 months after MPT. CPPS severity was obtained by the Brief Pain Inventory (BPI). Stronger perceptions of illness chronicity were correlated with less efficient CPM (r=0.488, P=0.002) and increased mechanical pain intensity (r=0.405, P=0.02). Lower perceptions of control over illness were associated with enhanced mTS (r=0.399, P=0.01). Higher BPI scores were correlated with emotional representations ("negative emotional representations") and severe consequences due to CPPS. Regression analyses revealed that negative IPs predict less efficient MPT. Cognitive representations play a unique role in CPPS expression and MPT outcomes. The interplay between negative IPs and a pro-nociceptive modulation profile, mediated by enhanced facilitatory and reduced inhibitory processes, may be involved in the manifestation of CPPS.

Continuous fever-range heat stress induces thermotolerance in odontoblast-lineage cells.

PubMed

Morotomi, Takahiko; Kitamura, Chiaki; Okinaga, Toshinori; Nishihara, Tatsuji; Sakagami, Ryuji; Anan, Hisashi

2014-07-01

Heat shock during restorative procedures can trigger damage to the pulpodentin complex. While severe heat shock has toxic effects, fever-range heat stress exerts beneficial effects on several cells and tissues. In this study, we examined whether continuous fever-range heat stress (CFHS) has beneficial effects on thermotolerance in the rat clonal dental pulp cell line with odontoblastic properties, KN-3. KN-3 cells were cultured at 41°C for various periods, and the expression level of several proteins was assessed by Western blot analysis. After pre-heat-treatment at 41°C for various periods, KN-3 cells were exposed to lethal severe heat shock (LSHS) at 49°C for 10min, and cell viability was examined using the MTS assay. Additionally, the expression level of odontoblast differentiation makers in surviving cells was examined by Western blot analysis. CFHS increased the expression levels of several heat shock proteins (HSPs) in KN-3 cells, and induced transient cell cycle arrest. KN-3 cells, not pre-heated or exposed to CFHS for 1 or 3h, died after exposure to LSHS. In contrast, KN-3 cells exposed to CFHS for 12h were transiently lower on day 1, but increased on day 3 after LSHS. The surviving cells expressed odontoblast differentiation markers, dentine sialoprotein and dentine matrix protein-1. These results suggest that CFHS for 12h improves tolerance to LSHS by inducing HSPs expression and cell cycle arrest in KN-3 cells. The appropriate pretreatment with continuous fever-range heat stress can provide protection against lethal heat shock in KN-3 cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

Health risks and precautions for visitors to the Tokyo 2020 Olympic and Paralympic Games.

PubMed

Nakamura, Sachiko; Wada, Koji; Yanagisawa, Naoki; Smith, Derek R

In 2020, Japan will host the Tokyo Olympic and Paralympic Games in 2020 (Tokyo 2020) which will involve a large population influx from various countries to Tokyo, the most populated city in Japan. We summarize the potential health risks for visitors to Tokyo 2020, related to communicable disease risks and other health threats, based on recent national and local surveillance reports. We reviewed up-to-date surveillance reports published by the National Institute of Infectious Diseases and Tokyo Metropolitan Infectious Disease Surveillance Center. Communicable disease risks for vaccine-preventable illnesses such as measles and rubella, as well as food and waterborne diseases represent the most likely risks. The risk of acquiring vector-borne diseases is considered low in Japan. On the other hand, however, heat-related illness represents a potential risk, as Tokyo 2020 is scheduled during the hottest season in Japan, with temperatures generally expected to exceed 30 °C. Maintaining an up-to-date routine vaccination schedule is highly recommended for visitors attending the Tokyo 2020 and appropriate hygiene measures for food and waterborne diseases as well as health promotion for heat-related illness. It may also be useful to increase the number of multilingual triage clinicians whom can be placed within emergency departments during the Tokyo 2020 to provide first contact services and coordination of emergency care among non-Japanese speaking visitors to Tokyo. Copyright © 2018. Published by Elsevier Ltd.

Heat transfer in a microvascular network: the effect of heart rate on heating and cooling in reptiles (Pogona barbata and Varanus varius).

PubMed

Seebacher, F

2000-03-21

Thermally-induced changes in heart rate and blood flow in reptiles are believed to be of selective advantage by allowing animal to exert some control over rates of heating and cooling. This notion has become one of the principal paradigms in reptilian thermal physiology. However, the functional significance of changes in heart rate is unclear, because the effect of heart rate and blood flow on total animal heat transfer is not known. I used heat transfer theory to determine the importance of heat transfer by blood flow relative to conduction. I validated theoretical predictions by comparing them with field data from two species of lizard, bearded dragons (Pogona barbata) and lace monitors (Varanus varius). Heart rates measured in free-ranging lizards in the field were significantly higher during heating than during cooling, and heart rates decreased with body mass. Convective heat transfer by blood flow increased with heart rate. Rates of heat transfer by both blood flow and conduction decreased with mass, but the mass scaling exponents were different. Hence, rate of conductive heat transfer decreased more rapidly with increasing mass than did heat transfer by blood flow, so that the relative importance of blood flow in total animal heat transfer increased with mass. The functional significance of changes in heart rate and, hence, rates of heat transfer, in response to heating and cooling in lizards was quantified. For example, by increasing heart rate when entering a heating environment in the morning, and decreasing heart rate when the environment cools in the evening a Pogona can spend up to 44 min longer per day with body temperature within its preferred range. It was concluded that changes in heart rate in response to heating and cooling confer a selective advantage at least on reptiles of mass similar to that of the study animals (0. 21-5.6 kg). Copyright 2000 Academic Press.

Relationship between physical occupational exposures and health on semen quality: data from the Longitudinal Investigation of Fertility and the Environment (LIFE) Study.

PubMed

Eisenberg, Michael L; Chen, Zhen; Ye, Aijun; Buck Louis, Germaine M

2015-05-01

To study the relationship among occupation, health, and semen quality in a cohort of men attempting to conceive. Observational prospective cohort. Not applicable. A total of 501 couples discontinuing contraception were followed for 1 year while trying to conceive; 473 men (94%) provided one semen sample, and 80% provided a second sample. None. Semen data obtained through at-home semen collection with next-day analysis/quantification. In all, complete data were available for 456 men, with a mean age of 31.8 years. Work-related heavy exertion was consistently associated with lower semen concentration and total sperm count. Thirteen percent of men who reported heavy exertion displayed oligospermia, compared with 6% who did not report workplace exertion. Shift work, night work, vibration, noise, heat, and prolonged sitting were not associated with semen quality. Men with high blood pressure had significantly lower strict morphology scores compared with normotensive men (17% vs. 21%). In contrast, hyperlipidemia, diabetes, and composite of total comorbidities were not associated with semen quality. The number of medications a man was taking as a proxy of health status was associated with semen quality. There was a negative association between number of medications and sperm count. A negative relationship among occupational exertion, hypertension, and the number of medications with semen quality was identified. As these are potentially modifiable factors, further research should determine whether treatment or cessation may improve male fecundity. Copyright © 2015 American Society for Reproductive Medicine. All rights reserved.

Biophysical aspects of human thermoregulation during heat stress.

PubMed

Cramer, Matthew N; Jay, Ollie

2016-04-01

Humans maintain a relatively constant core temperature through the dynamic balance between endogenous heat production and heat dissipation to the surrounding environment. In response to metabolic or environmental disturbances to heat balance, the autonomic nervous system initiates cutaneous vasodilation and eccrine sweating to facilitate higher rates of dry (primarily convection and radiation) and evaporative transfer from the body surface; however, absolute heat losses are ultimately governed by the properties of the skin and the environment. Over the duration of a heat exposure, the cumulative imbalance between heat production and heat dissipation leads to body heat storage, but the consequent change in core temperature, which has implications for health and safety in occupational and athletic settings particularly among certain clinical populations, involves a complex interaction between changes in body heat content and the body's morphological characteristics (mass, surface area, and tissue composition) that collectively determine the body's thermal inertia. The aim of this review is to highlight the biophysical aspects of human core temperature regulation by outlining the principles of human energy exchange and examining the influence of body morphology during exercise and environmental heat stress. An understanding of the biophysical factors influencing core temperature will enable researchers and practitioners to better identify and treat individuals/populations most vulnerable to heat illness and injury during exercise and extreme heat events. Further, appropriate guidelines may be developed to optimize health, safety, and work performance during heat stress. Copyright © 2016 Elsevier B.V. All rights reserved.

Excessive occupational heat exposure: a significant ergonomic challenge and health risk for current and future workers

PubMed Central

2014-01-01

Occupational heat exposure threatens the health of a worker not only when heat illness occurs but also when a worker’s performance and work capacity is impaired. Occupational contexts that involve hot and humid climatic conditions, heavy physical workloads and/or protective clothing create a strenuous and potentially dangerous thermal load for a worker. There are recognized heat prevention strategies and international thermal ergonomic standards to protect the worker. However, such standards have been developed largely in temperate western settings, and their validity and relevance is questionable for some geographical, cultural and socioeconomic contexts where the risk of excessive heat exposure can be high. There is evidence from low- and middle-income tropical countries that excessive heat exposure remains a significant issue for occupational health. Workers in these countries are likely to be at high risk of excessive heat exposure as they are densely populated, have large informal work sectors and are expected to experience substantial increases in temperature due to global climate change. The aim of this paper is to discuss current and future ergonomic risks associated with working in the heat as well as potential methods for maintaining the health and productivity of workers, particularly those most vulnerable to excessive heat exposure. PMID:25057350

Invited review: heat stress effects during late gestation on dry cows and their calves.

PubMed

Tao, S; Dahl, G E

2013-07-01

In dairy cattle, late gestation is a critical period for fetal growth and physiological transition into the next lactation. Environmental factors, such as temperature and light, exert dramatic effects on the production, health, and well-being of animals during this period and after parturition. The aim of this review was to introduce effects of heat stress during late gestation on dairy cattle, and discuss the biological mechanisms that underlie the observed production and health responses in the dam and her fetus. Relative to cooled cows, cows that are heat stressed during late gestation have impaired mammary growth before parturition and decreased milk production in the subsequent lactation. In response to higher milk yield, cows cooled prepartum undergo a series of homeorhetic adaptations in early lactation to meet higher demand for milk synthesis compared with heat-stressed cows, but no direct effect of environmental heat stress on metabolism exists during the dry period. Prepartum cooling improves immune status of transition cows and evidence suggests that altered prolactin signaling in immune cells mediates the effects of heat stress on immune function. Late-gestation heat stress compromises placental development, which results in fetal hypoxia, malnutrition, and eventually fetal growth retardation. Maternal heat stress may also have carryover effects on the postnatal growth of offspring, but direct evidence is still lacking. Emerging evidence suggests that offspring from prepartum heat-stressed cows have compromised passive immunity and impaired cell-mediated immune function compared with those from cooled cows. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Exercise activates compensatory thermoregulatory reaction in rats: a modeling study

PubMed Central

Yoo, Yeonjoo; LaPradd, Michelle; Kline, Hannah; Zaretskaia, Maria V.; Behrouzvaziri, Abolhassan; Rusyniak, Daniel E.; Molkov, Yaroslav I.

2015-01-01

The importance of exercise is increasingly emphasized for maintaining health. However, exercise itself can pose threats to health such as the development of exertional heat shock in warm environments. Therefore, it is important to understand how the thermoregulation system adjusts during exercise and how alterations of this can contribute to heat stroke. To explore this we measured the core body temperature of rats (Tc) running for 15 min on a treadmill at various speeds in two ambient temperatures (Ta = 25°C and 32°C). We assimilated the experimental data into a mathematical model that describes temperature changes in two compartments of the body, representing the muscles and the core. In our model the core body generates heat to maintain normal body temperature, and dissipates it into the environment. The muscles produce additional heat during exercise. According to the estimation of model parameters, at Ta = 25°C, the heat generation in the core was progressively reduced with the increase of the treadmill speed to compensate for a progressive increase in heat production by the muscles. This compensation was ineffective at Ta = 32°C, which resulted in an increased rate of heat accumulation with increasing speed, as opposed to the Ta = 25°C case. Interestingly, placing an animal on a treadmill increased heat production in the muscles even when the treadmill speed was zero. Quantitatively, this “ready-to-run” phenomenon accounted for over half of the heat generation in the muscles observed at maximal treadmill speed. We speculate that this anticipatory response utilizes stress-related circuitry. PMID:26472864

Work production of quantum rotor engines

NASA Astrophysics Data System (ADS)

Seah, Stella; Nimmrichter, Stefan; Scarani, Valerio

2018-04-01

We study the mechanical performance of quantum rotor heat engines in terms of common notions of work using two prototypical models: a mill driven by the heat flow from a hot to a cold mode, and a piston driven by the alternate heating and cooling of a single working mode. We evaluate the extractable work in terms of ergotropy, the kinetic energy associated to net directed rotation, as well as the intrinsic work based on the exerted torque under autonomous operation, and we compare them to the energy output for the case of an external dissipative load and for externally driven engine cycles. Our results connect work definitions from both physical and information-theoretical perspectives. In particular, we find that apart from signatures of angular momentum quantization, the ergotropy is consistent with the intuitive notion of work in the form of net directed motion. It also agrees with the energy output to an external load or agent under optimal conditions. This sets forth a consistent thermodynamical description of rotating quantum motors, flywheels, and clocks.

Plasma dynamics near critical density inferred from direct measurements of laser hole boring

NASA Astrophysics Data System (ADS)

Gong, Chao; Tochitsky, Sergei Ya.; Fiuza, Frederico; Pigeon, Jeremy J.; Joshi, Chan

2016-06-01

We have used multiframe picosecond optical interferometry to make direct measurements of the hole boring velocity, vHB, of the density cavity pushed forward by a train of C O2 laser pulses in a near critical density helium plasma. As the pulse train intensity rises, the increasing radiation pressure of each pulse pushes the density cavity forward and the plasma electrons are strongly heated. After the peak laser intensity, the plasma pressure exerted by the heated electrons strongly impedes the hole boring process and the vHB falls rapidly as the laser pulse intensity falls at the back of the laser pulse train. A heuristic theory is presented that allows the estimation of the plasma electron temperature from the measurements of the hole boring velocity. The measured values of vHB, and the estimated values of the heated electron temperature as a function of laser intensity are in reasonable agreement with those obtained from two-dimensional numerical simulations.

Plasma dynamics near critical density inferred from direct measurements of laser hole boring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, Chao; Tochitsky, Sergei Ya.; Fiuza, Frederico

Here, we use multiframe picosecond optical interferometry to make direct measurements of the hole boring velocity, vHB, of the density cavity pushed forward by a train of CO 2 laser pulses in a near critical density helium plasma. As the pulse train intensity rises, the increasing radiation pressure of each pulse pushes the density cavity forward and the plasma electrons are strongly heated. After the peak laser intensity, the plasma pressure exerted by the heated electrons strongly impedes the hole boring process and the vHB falls rapidly as the laser pulse intensity falls at the back of the laser pulsemore » train. We present a heuristic theory that allows the estimation of the plasma electron temperature from the measurements of the hole boring velocity. Furthermore, the measured values of v HB, and the estimated values of the heated electron temperature as a function of laser intensity are in reasonable agreement with those obtained from two-dimensional numerical simulations.« less

Repeat work bouts increase thermal strain for Australian firefighters working in the heat.

PubMed

Walker, Anthony; Argus, Christos; Driller, Matthew; Rattray, Ben

2015-01-01

Firefighters regularly re-enter fire scenes during long duration emergency events with limited rest between work bouts. It is unclear whether this practice is impacting on the safety of firefighters. To evaluate the effects of multiple work bouts on firefighter physiology, strength, and cognitive performance when working in the heat. Seventy-seven urban firefighters completed two 20-minute simulated search and rescue tasks in a heat chamber (105 ± 5°C), separated by a 10-minute passive recovery. Core and skin temperature, rate of perceived exertion (RPE), thermal sensation (TS), grip strength, and cognitive changes between simulations were evaluated. Significant increases in core temperature and perceptual responses along with declines in strength were observed following the second simulation. No differences for other measures were observed. A significant increase in thermal strain was observed when firefighters re-entered a hot working environment. We recommend that longer recovery periods or active cooling methods be employed prior to re-entry.

Plasma dynamics near critical density inferred from direct measurements of laser hole boring.

PubMed

Gong, Chao; Tochitsky, Sergei Ya; Fiuza, Frederico; Pigeon, Jeremy J; Joshi, Chan

2016-06-01

We have used multiframe picosecond optical interferometry to make direct measurements of the hole boring velocity, v_{HB}, of the density cavity pushed forward by a train of CO_{2} laser pulses in a near critical density helium plasma. As the pulse train intensity rises, the increasing radiation pressure of each pulse pushes the density cavity forward and the plasma electrons are strongly heated. After the peak laser intensity, the plasma pressure exerted by the heated electrons strongly impedes the hole boring process and the v_{HB} falls rapidly as the laser pulse intensity falls at the back of the laser pulse train. A heuristic theory is presented that allows the estimation of the plasma electron temperature from the measurements of the hole boring velocity. The measured values of v_{HB}, and the estimated values of the heated electron temperature as a function of laser intensity are in reasonable agreement with those obtained from two-dimensional numerical simulations.

Plasma dynamics near critical density inferred from direct measurements of laser hole boring

DOE PAGES

Gong, Chao; Tochitsky, Sergei Ya.; Fiuza, Frederico; ...

2017-06-24

Here, we use multiframe picosecond optical interferometry to make direct measurements of the hole boring velocity, vHB, of the density cavity pushed forward by a train of CO 2 laser pulses in a near critical density helium plasma. As the pulse train intensity rises, the increasing radiation pressure of each pulse pushes the density cavity forward and the plasma electrons are strongly heated. After the peak laser intensity, the plasma pressure exerted by the heated electrons strongly impedes the hole boring process and the vHB falls rapidly as the laser pulse intensity falls at the back of the laser pulsemore » train. We present a heuristic theory that allows the estimation of the plasma electron temperature from the measurements of the hole boring velocity. Furthermore, the measured values of v HB, and the estimated values of the heated electron temperature as a function of laser intensity are in reasonable agreement with those obtained from two-dimensional numerical simulations.« less

Repeat work bouts increase thermal strain for Australian firefighters working in the heat

PubMed Central

Walker, Anthony; Argus, Christos; Driller, Matthew; Rattray, Ben

2015-01-01

Background: Firefighters regularly re-enter fire scenes during long duration emergency events with limited rest between work bouts. It is unclear whether this practice is impacting on the safety of firefighters. Objectives:To evaluate the effects of multiple work bouts on firefighter physiology, strength, and cognitive performance when working in the heat. Methods: Seventy-seven urban firefighters completed two 20-minute simulated search and rescue tasks in a heat chamber (105 ± 5°C), separated by a 10-minute passive recovery. Core and skin temperature, rate of perceived exertion (RPE), thermal sensation (TS), grip strength, and cognitive changes between simulations were evaluated. Results: Significant increases in core temperature and perceptual responses along with declines in strength were observed following the second simulation. No differences for other measures were observed. Conclusions: A significant increase in thermal strain was observed when firefighters re-entered a hot working environment. We recommend that longer recovery periods or active cooling methods be employed prior to re-entry. PMID:25849044

Heat shock proteins and toll-like receptors.

PubMed

Asea, Alexzander

2008-01-01

Researchers have only just begun to elucidate the relationship between heat shock proteins (HSP) and Toll-like receptors (TLR). HSP were originally described as an intracellular molecular chaperone of naïve, aberrantly folded, or mutated proteins and primarily implicated as a cytoprotective protein when cells are exposed to stressful stimuli. However, recent studies have ascribed novel functions to the Hsp70 protein depending on its localization: Surface-bound Hsp70 specifically activate natural killer (NK) cells, while Hsp70 released into the extracellular milieu specifically bind to Toll-like receptors (TLR) 2 and 4 on antigen-presenting cells (APC) and exerts immunoregulatory effects, including upregulation of adhesion molecules, co-stimulatory molecule expression, and cytokine and chemokine release-a process known as the chaperokine activity of Hsp70. This chapter discusses the most recent advances in the understanding of heat shock protein (HSP) and TLR interactions in general and highlights recent findings that demonstrate Hsp70 is a ligand for TLR and its biological significance.

Numerical Investigation of the Effect of Some Parameters on Temperature Field and Kerf Width in Laser Cutting Process

NASA Astrophysics Data System (ADS)

Kheloufi, Karim; Amara, El Hachemi

A transient numerical model is developed to study the temperature field and the kerf shape during laser cutting process. The Fresnel absorption model is used to handle the absorption of the incident wave by the surface of the liquid metal and the enthalpy-porosity technique is employed to account for the latent heat during melting and solidification of the material. The VOF method is used to track the evolution of the shape of the kerf. Physical phenomena occurring at the liquid/gas interface, including friction force and pressure force exerted by the gas jet and the heat absorbed by the surface, are incorporated into the governing equations as source terms. Temperature and velocity distribution, and kerf shape are investigated.

Atmospheric radiation measurement program facilities newsletter, August 2001.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holdridge, D. J.,ed.

2001-09-04

Summer 2001 Heat Wave--This summer has proved to be downright hot in the Southern Great Plains states. The temperatures soared to record-setting levels. The state of Oklahoma saw its fourth hottest July since 1895, while Kansas experienced its seventh warmest. The average temperature throughout most of Oklahoma for the month of July was 2.5-5.5 F above normal. The highest temperature recorded in the region during July was 107 F in Oklahoma City. Wichita, Kansas, had 17 July days with recorded temperatures of 100 F or above, while Medicine Lodge, Kansas, had 21. In addition, Oklahoma suffered its ninth driest July,more » with precipitation levels much below normal. Kansas fared better, receiving above-normal precipitation amounts. Nevertheless, regional July rainfall averaged 1.5-3.0 inches below normal. Not only is a summer heat wave uncomfortable, but it can also be dangerous. The National Weather Service (NWS) has increased efforts to alert the public to the hazards of heat waves. Prolonged excessive heat and humidity stress the human body and can, in some cases, cause death. The NWS has devised a heat index that is a measure of the heat we perceive as a function of air temperature and humidity. A heat index chart displays different zones from caution to extreme danger, much like a wind chill index chart used in the winter. The values represent conditions of light winds and shade. Thus, in full sunshine heat index values can increase by 15 F. Exposure to winds in hot, dry weather can be equally dangerous. The NWS sends out alerts when the heat index is expected to reach values with significant potential impact. The danger of heat-related illness increases with the number of consecutive days with high heat and humidity levels. Heat and humidity take their toll faster on the elderly, small children, and those with respiratory health problems. Heat-related illnesses come in several forms with different symptoms. From common sunburns to heat stroke, these heat disorders need to be addressed promptly. Sunburn is something most of us have experienced. Severe burns can be dangerous and should be treated by a physician. Heat cramps (painful muscle cramps, usually of the leg muscles) are typically accompanied by heavy sweating. Heat exhaustion symptoms include sweating; weakness; cold, pale, clammy skin; fainting; and vomiting. Heat stroke (also called sunstroke), the most serious heat disorder, can cause the body temperature to rise to 106 F or higher. The skin becomes hot and dry, and the pulse is rapid. Heat stroke is a severe medical emergency and can be fatal. Everyone can take common-sense precautions to ease the danger of a heat wave. Reduce strenuous exercise and outdoor activities. Reschedule these activities for a cooler time of day or move them to an air-conditioned indoor location. Wear lightweight, light-colored clothing to help maintain a normal body temperature and reflect sunlight and heat. Drink plenty of non-alcoholic fluids, especially water, to help maintain good hydration, and eat light meals. Stay out of the sun if possible and spend time in air-conditioned places to reduce the stress of summer heat.« less

A 3-D Mathematical Model to Identify Organ-Specific Risks in Rats During Thermal Stress

DTIC Science & Technology

2013-01-01

1800. This response is anticipatory of the active period when feeding, grooming, and other behaviors are manifested during the normal circadian cycle... Sports Exerc 37: 1338–1344, 2005. 11. Casa DJ, Armstrong LE, Ganio MS, Yeargin SW. Exertional heat stroke in competitive athletes. Curr Sports Med Rep 4...an integra- tive view of the final common pathway. Scand J Med Sci Sports 21: 742–748, 2011. 25. Even PC, Rolland V, Roseau S, Bouthegourd JC, Tome D

The Effects of Implementing TopModel Concepts in the Noah Model

NASA Technical Reports Server (NTRS)

Peters-Lidard, C. D.; Houser, Paul R. (Technical Monitor)

2002-01-01

Topographic effects on runoff generation have been documented observationally (e.g., Dunne and Black, 1970) and are the subject of the physically based rainfall-runoff model TOPMODEL (Beven and Kirkby, 1979; Beven, 1986a;b) and its extensions, which incorporate variable soil transmissivity effects (Sivapalan et al, 1987, Wood et al., 1988; 1990). These effects have been shown to exert significant control over the spatial distribution of runoff, soil moisture and evapotranspiration, and by extension, the latent and sensible heat fluxes

Substantial convection and precipitation enhancements by ultrafine aerosol particles

NASA Astrophysics Data System (ADS)

Fan, Jiwen; Rosenfeld, Daniel; Zhang, Yuwei; Giangrande, Scott E.; Li, Zhanqing; Machado, Luiz A. T.; Martin, Scot T.; Yang, Yan; Wang, Jian; Artaxo, Paulo; Barbosa, Henrique M. J.; Braga, Ramon C.; Comstock, Jennifer M.; Feng, Zhe; Gao, Wenhua; Gomes, Helber B.; Mei, Fan; Pöhlker, Christopher; Pöhlker, Mira L.; Pöschl, Ulrich; de Souza, Rodrigo A. F.

2018-01-01

Ultrafine aerosol particles (smaller than 50 nanometers in diameter) have been thought to be too small to affect cloud formation. Fan et al. show that this is not the case. They studied the effect of urban pollution transported into the otherwise nearly pristine atmosphere of the Amazon. Condensational growth of water droplets around the tiny particles releases latent heat, thereby intensifying atmospheric convection. Thus, anthropogenic ultrafine aerosol particles may exert a more important influence on cloud formation processes than previously believed.

Experimental study of the form of "hot" steel particles on the ignition characteristics of liquid fuels

NASA Astrophysics Data System (ADS)

Zakharevich, Arkadiy V.

2015-01-01

The results of an experimental study of laws governing the ignition of liquid propellants (kerosene, diesel fuel and petroleum residue) by the single spherical steel particle heated to high temperatures are presented. Is carried out the comparison of the ignition delay times of the investigated flammable substances by the particles in the sphere and disk forms. It is established that the particle shape does not exert a substantial influence on the ignition process characteristics.

Religiosity and religious delusions in schizophrenia - An observational study in a Hindu population.

PubMed

Mishra, Anand; Das, Basudeb; Goyal, Nishant

2018-02-01

Religion exerts a significant effect on the lives of many individuals including people with mental illness. As evidences keep accumulating, role of religion in mental illness is gaining importance. The study was designed to study the effects of religiosity on religious delusions, its presentation, acute course and outcome in schizophrenia. The study was a naturalistic observational study. Subjects with schizophrenia were grouped into those with religious (RG) and with non-religious delusions (NG). Their premorbid religiosity was assessed with Brief Multi-dimensional measurement of Religiosity/spirituality (BMMRS) and were rated on Scale for Assessment of Positive Symptoms (SAPS), Brown's Assessment of Belief Scale (BABS) and Positive and Negative Symptom Scale (PANSS) at baseline and 4 weeks. Scores on private religious practices, baseline scores of SAPS, BABS & PANSS and duration of untreated psychosis (DUP) were significantly higher for RG in comparison to NG. On component analysis, higher scores were seen on private praying, watching religious programs on TV, reading religious books and prayers at meals. But no significant correlation was found between the private religious practices and the baseline scores of (DUP), SAPS, BABS, PANSS and outcome measure. Also no significant difference was noted in measures of improvement between groups. Private religious practices are more prominent in patients of schizophrenia with religious delusions and this group of patient seems to present with a more severe illness, and a longer duration of untreated psychosis in comparison to those with non-religious delusions. Copyright © 2017 Elsevier B.V. All rights reserved.

Early Socioeconomic Adversity and Young Adult Physical Illness: The Role of Body Mass Index and Depressive Symptoms

PubMed Central

Wickrama, K. A. S.; Kwon, Josephine A.; Oshri, Assaf; Lee, Tae Kyoung

2014-01-01

Purpose The present study investigated the psycho-physiological inter and intra-individual processes that mediate the linkage between childhood/adolescent socioeconomic adversities and adult health outcomes. Specifically, the proposed model examined the roles of youth depressive symptoms and BMI trajectories as mediators that explain the link between early adversity and young adults’ general health and physical illnesses after controlling for gender, race/ethnicity, and earlier general health reports. Methods Using a nationally representative sample of 12,424 from National Longitudinal Study of Adolescent Health (Add Health), this study used growth curve modeling to consider both the severity (initial level) as well as the change over time (deterioration or elevation) as psycho-physiological mediators, thereby acknowledging multiple facets of depressive symptoms and BMI trajectories as psych-physiological mediators of early adversity to adult health. Results Results provide evidence for (a) the influence of early childhood and early adolescent cumulative socioeconomic adversity on both the initial levels and changes over time of depressive symptoms and BMI and (b) the independent influences depressive symptoms and BMI trajectories on the general health and the physical illnesses of young adults Conclusions These findings contribute valuable knowledge to existing research by elucidating how early adversity exerts an enduring long-term influence on physical health problems in young adulthood; further, this information suggests effective intervention and prevention programs should incorporate multiple facets (severity and change over time) of multiple mechanisms (psychological and physiological). PMID:24856408

Newspaper representations of mental illness and the impact of the reporting of "events" on social policy: the "framing" of Isabel Schwarz and Jonathan Zito.

PubMed

Paterson, B

2006-06-01

Concerns have been raised internationally about the role of the media in influencing public opinion and by implication, social policy on mental health issues. In particular, anxieties have been expressed that an "excessive" focus by the news media on violence in association with mental illness may reinforce pre-existing stereotypes and by escalating public concerns lead to the adoption of policies which place a high priority on the safety of the public. Such assertions are often contained in the numerous studies that record a seemingly disproportionate number of stories featuring violence in association with mental health. What is, however, almost invariably lacking is a developed theory of agency that explains how or why such depictions of mental illness might exert an influence on social policy. This paper critically examines the potential significance of the way in which responsibility for events is constructed for social policy by means of a discourse analysis, inspired by the genealogical work of Michel Foucault. It uses the device of "frames" originally developed by Goffman to explore the nature of newspaper coverage of two deaths to which causal responsibility for changes in the nature of English social policy in mental health has been attributed. Results presented suggest that attempts to assert a causal influence between media coverage and changes in the nature of social policy must engage with the question of agency.

Genetic component of sensitivity to heat stress for nonreturn rate of Brazilian Holstein cattle.

PubMed

Santana, M L; Bignardi, A B; Stefani, G; El Faro, L

2017-08-01

The objectives of the present study were: 1) to investigate variation in the genetic component of heat stress for nonreturn rate at 56 days after first artificial insemination (NR56); 2) to identify and characterize the genotype by environment interaction (G × E) due to heat stress for NR56 of Brazilian Holstein cattle. A linear random regression model (reaction norm model) was applied to 51,748 NR56 records of 28,595 heifers and multiparous cows. The decline in NR56 due to heat stress was more pronounced in milking cows compared to heifers. The age of females at first artificial insemination and temperature-humidity index (THI) exerted an important influence on the genetic parameters of NR56. Several evidence of G × E on NR56 were found as the high slope/intercept ratio and frequent intersection of reaction norms. Additionally, the genetic correlation between NR56 at opposite extremes of the THI scale reached estimates below zero, indicating that few of the same genes are responsible for NR56 under conditions of thermoneutrality and heat stress. The genetic evaluation and selection for NR56 in Holstein cattle reared under (sub)tropical conditions should therefore take into consideration the genetic variation on age at insemination and G × E due to heat stress. Copyright © 2017 Elsevier Inc. All rights reserved.

Preservation of Cognitive Performance with Age during Exertional Heat Stress under Low and High Air Velocity

PubMed Central

Wright Beatty, Heather E.; Keillor, Jocelyn M.; Hardcastle, Stephen G.; Boulay, Pierre; Kenny, Glen P.

2015-01-01

Older adults may be at greater risk for occupational injuries given their reduced capacity to dissipate heat, leading to greater thermal strain and potentially cognitive decrements. Purpose. To examine the effects of age and increased air velocity, during exercise in humid heat, on information processing and attention. Methods. Nine young (24 ± 1 years) and 9 older (59 ± 1 years) males cycled 4 × 15 min (separated by 15 min rest) at a fixed rate of heat production (400 W) in humid heat (35°C, 60% relative humidity) under 0.5 (low) and 3.0 (high) m·s−1 air velocity wearing coveralls. At rest, immediately following exercise (end exercise), and after the final recovery, participants performed an abbreviated paced auditory serial addition task (PASAT, 2 sec pace). Results. PASAT numbers of correct responses at end exercise were similar for young (low = 49 ± 3; high = 51 ± 3) and older (low = 46 ± 5; high = 47 ± 4) males and across air velocity conditions, and when scored relative to age norms. Psychological sweating, or an increased sweat rate with the administration of the PASAT, was observed in both age groups in the high condition. Conclusion. No significant decrements in attention and speeded information processing were observed, with age or altered air velocity, following intermittent exercise in humid heat. PMID:25874223

Thermocapillary flow with evaporation and condensation and its effect on liquid retention in low-G fluid acquisition devices

NASA Technical Reports Server (NTRS)

Schmidt, George R.

1994-01-01

The steady motion, thermal and free surface behavior of a volatile, wetting liquid in microgravity are studied using scaling and numerical techniques. The objective is to determine whether the thermocapillary and two-phase convection arising from thermodynamic nonequilibrium along the porous surfaces of spacecraft liquid acquisition devices could cause the retention failures observed with liquid hydrogen and heated vapor pressurant. Why these devices seem immune to retention loss when pressurized with heated helium or heated directly through the porous structure was also examined. Results show that highly wetting fluids exhibit large negative and positive dynamic pressure gradients towards the meniscus interline when superheated and subcooled, respectively. With superheating, the pressure variation and recoil force arising from liquid/vapor phase change exert the same influence on surface morphology and promote retention. With subcooling, however, the pressure distribution produces a suction that degrades mechanical equilibrium of the surface. This result indicates that thermocapillary-induced deformation arising from subcooling and condensation is the likely cause for retention loss. In addition, increasing the level of nonequilibrium by reducing accommodation coefficient suppresses deformation and explains why this failure mode does not occur in instances of direct screen heating or pressurization with a heated inert gas.

Evaluation of Working Fluids for Organic Rankine Cycle Based on Exergy Analysis

NASA Astrophysics Data System (ADS)

Setiawan, D.; Subrata, I. D. M.; Purwanto, Y. A.; Tambunan, A. H.

2018-05-01

One of the crucial aspects to determine the performance of Organic Rankine Cycle (ORC) is the selection of appropriate working fluids. This paper describes the simulative performance of several organic fluid and water as working fluid of an ORC based on exergy analysis with a heat source from waste heat recovery. The simulation was conducted by using Engineering Equation Solver (EES). The effect of several parameters and thermodynamic properties of working fluid was analyzed, and part of them was used as variables for the simulation in order to determine their sensitivity to the exergy efficiency changes. The results of this study showed that water is not appropriate to be used as working fluid at temperature lower than 130 °C, because the expansion process falls in saturated area. It was also found that Benzene had the highest exergy efficiency, i.e. about 10.49%, among the dry type working fluid. The increasing turbine inlet temperature did not lead to the increase of exergy efficiency when using organic working fluids with critical temperature near heat source temperature. Meanwhile, exergy efficiency decreasing linearly with the increasing condenser inlet temperature. In addition, it was found that working fluid with high latent heat of vaporization and specific heat exert in high exergy efficiency.

Effects of packaging and heat transfer kinetics on drug-product stability during storage under uncontrolled temperature conditions.

PubMed

Nakamura, Toru; Yamaji, Takayuki; Takayama, Kozo

2013-05-01

To predict the stability of pharmaceutical preparations under uncontrolled temperature conditions accurately, a method to compute the average reaction rate constant taking into account the heat transfer from the atmosphere to the product was developed. The average reaction rate constants computed with taken into consideration heat transfer (κ(re) ) were then compared with those computed without taking heat transfer into consideration (κ(in) ). The apparent thermal diffusivity (κ(a) ) exerted some influence on the average reaction rate constant ratio (R, R = κ(re) /κ(in) ). In the regions where the κ(a) was large (above 1 h(-1) ) or very small, the value of R was close to 1. On the contrary, in the middle region (0.001-1 h(-1) ), the value of R was less than 1.The κ(a) of the central part of a large-size container and that of the central part of a paper case of 10 bottles of liquid medicine (100 mL) fell within this middle region. On the basis of the above-mentioned considerations, heat transfer may need to be taken into consideration to enable a more accurate prediction of the stability of actual pharmaceutical preparations under nonisothermal atmospheres. Copyright © 2013 Wiley Periodicals, Inc.

Physiology and Endocrinology Symposium: influence of cattle genotype (Bos indicus vs. Bos taurus) on oocyte and preimplantation embryo resistance to increased temperature.

PubMed

Paula-Lopes, F F; Lima, R S; Satrapa, R A; Barros, C M

2013-03-01

High environmental temperatures during the hot months of the year reduce reproductive performance in cattle. Summer heat stress depression in fertility is a multifactorial problem; however, there is evidence that the bovine germinal vesicle and maturing oocyte, as well as the early embryo, are major targets of the deleterious effects of heat stress. Such adverse effects are less pronounced in heat-tolerant breeds (Bos indicus) than heat-sensitive breeds (Bos taurus). This genetic variation results from the greater thermoregulatory ability and cellular thermoresistance of heat-tolerant breeds. Heat-induced oocyte cellular damage occurs in both cytoplasmic and nuclear compartments. Heat shock has been shown to reduce oocyte nuclear maturation, induce apoptosis, compromise oocyte cytoskeleton, and impair oocyte mitochondrial function and developmental competence. However, the oocyte cytoplasm is more susceptible to heat shock than the nucleus. This effect is greater for Bos taurus than Bos indicus oocytes. The detrimental effects of heat shock are also critical during the first cleavage divisions when most of the embryonic genome is inactive; however, the bovine embryo becomes more resistant to increased temperature as it proceeds through development. Several studies demonstrated that Bos indicus embryos are more thermotolerant than Bos taurus embryos. Adaptive changes involved in acquisition of thermotolerance are likely derived from changes in gene expression and (or) activity of biochemical molecules that control cellular functions against stress. Recently, molecules such as IGF-I and caspase inhibitor z-DEVD-fmk have been shown to exert a thermoprotective role, rescuing heat-induced oocyte and embryo cellular damage and developmental competence. Therefore, cattle genotype and thermoprotective molecules can be considered as an alternative to modulate the effects of increased temperature in reproductive function.

Pasteurization of shell eggs using radio frequency heating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geveke, David J.; Bigley, Andrew B. W.; Brunkhorst, Christopher D.

The USDA-FSIS estimates that pasteurization of all shell eggs in the U.S. would reduce the annual number of illnesses by more than 110,000. However, less than 3% of shell eggs are commercially pasteurized. One of the main reasons for this is that the commercial hot water process requires as much as 60 min to complete. In the present study, a radio frequency (RF) apparatus was constructed, and a two-step process was developed that uses RF energy and hot water, to pasteurize eggs in less than half the time. In order to select an appropriate RF generator, the impedance of shellmore » eggs was measured in the frequency range of 10–70 MHz. The power density within the egg was modeled to prevent potential hotspots. Escherichia coli (ATCC 35218) was inoculated in the yolk to approximately 7.5 log CFU/ml. The combination process first heated the egg in 35.0 °C water for 3.5 min using 60 MHz RF energy. This resulted in the yolk being preferentially heated to 61 °C. Then, the egg was heated for an additional 20 min with 56.7 °C water. This two-step process reduced the population of E. coli by 6.5 log. The total time for the process was 23.5 min. By contrast, processing for 60 min was required to reduce the E. coli by 6.6 log using just hot water. The novel RF pasteurization process presented in this study was considerably faster than the existing commercial process. As a result, this should lead to an increase in the percentage of eggs being pasteurized, as well as a reduction of foodborne illnesses.« less

Pasteurization of shell eggs using radio frequency heating

DOE PAGES

Geveke, David J.; Bigley, Andrew B. W.; Brunkhorst, Christopher D.

2016-08-21

The USDA-FSIS estimates that pasteurization of all shell eggs in the U.S. would reduce the annual number of illnesses by more than 110,000. However, less than 3% of shell eggs are commercially pasteurized. One of the main reasons for this is that the commercial hot water process requires as much as 60 min to complete. In the present study, a radio frequency (RF) apparatus was constructed, and a two-step process was developed that uses RF energy and hot water, to pasteurize eggs in less than half the time. In order to select an appropriate RF generator, the impedance of shellmore » eggs was measured in the frequency range of 10–70 MHz. The power density within the egg was modeled to prevent potential hotspots. Escherichia coli (ATCC 35218) was inoculated in the yolk to approximately 7.5 log CFU/ml. The combination process first heated the egg in 35.0 °C water for 3.5 min using 60 MHz RF energy. This resulted in the yolk being preferentially heated to 61 °C. Then, the egg was heated for an additional 20 min with 56.7 °C water. This two-step process reduced the population of E. coli by 6.5 log. The total time for the process was 23.5 min. By contrast, processing for 60 min was required to reduce the E. coli by 6.6 log using just hot water. The novel RF pasteurization process presented in this study was considerably faster than the existing commercial process. As a result, this should lead to an increase in the percentage of eggs being pasteurized, as well as a reduction of foodborne illnesses.« less

Small Heat Shock Proteins in Redox Metabolism: Implications for Cardiovascular Diseases

PubMed Central

Christians, Elisabeth S.; Ishiwata, Takahiro; Benjamin, Ivor J.

2012-01-01

A timely review series on small heat shock proteins has to appropriately examine their fundamental properties and implications in the cardiovascular system since several members of this chaperone family exhibit robust expression in the myocardium and blood vessels. Due to energetic and metabolic demands, the cardiovascular system maintains a high mitochondrial activity but irreversible oxidative damage might ensue from increased production of reactive oxygen species. How equilibrium between their production and scavenging is achieved becomes paramount for physiological maintenance. For example, heat shock protein B1 (HSPB1) is implicated in maintaining this equilibrium or redox homeostasis by upholding the level of glutathione, a major redox mediator. Studies of gain or loss of function achieved by genetic manipulations have been highly informative for understanding the roles of those proteins. For example, genetic deficiency of several small heat shock proteins such as HSPB5 and HSPB2 is well-tolerated in heart cells whereas a single missense mutation causes human pathology. Such evidence highlights both the profound genetic redundancy observed among the multigene family of small heat shock proteins while underscoring the role proteotoxicity plays in driving disease pathogenesis. We will discuss the available data on small heat shock proteins in the cardiovascular system, redox metabolism and human diseases. From the medical perspective, we envision that such emerging knowledge of the multiple roles small heat shock proteins exert in the cardiovascular system will undoubtedly open new avenues for their identification and possible therapeutic targeting in humans. PMID:22710345

The Hsp72 and Hsp90α mRNA Responses to Hot Downhill Running Are Reduced Following a Prior Bout of Hot Downhill Running, and Occur Concurrently within Leukocytes and the Vastus Lateralis.

PubMed

Tuttle, James A; Chrismas, Bryna C R; Gibson, Oliver R; Barrington, James H; Hughes, David C; Castle, Paul C; Metcalfe, Alan J; Midgley, Adrian W; Pearce, Oliver; Kabir, Chindu; Rayanmarakar, Faizal; Al-Ali, Sami; Lewis, Mark P; Taylor, Lee

2017-01-01

The leukocyte heat shock response (HSR) is used to determine individual's thermotolerance. The HSR and thermotolerance are enhanced following interventions such as preconditioning and/or acclimation/acclimatization. However, it is unclear whether the leukocyte HSR is an appropriate surrogate for the HSR in other tissues implicated within the pathophysiology of exertional heat illnesses (e.g., skeletal muscle), and whether an acute preconditioning strategy (e.g., downhill running) can improve subsequent thermotolerance. Physically active, non-heat acclimated participants were split into two groups to investigate the benefits of hot downhill running as preconditioning strategy. A hot preconditioning group (HPC; n = 6) completed two trials (HPC1 HOTDOWN and HPC2 HOTDOWN ) of 30 min running at lactate threshold (LT) on -10% gradient in 30°C and 50% relative humidity (RH) separated by 7 d. A temperate preconditioning group (TPC; n = 5) completed 30 min running at LT on a -1% gradient in 20°C and 50% (TPC1 TEMPFLAT ) and 7 d later completed 30 min running at LT on -10% gradient in 30°C and 50% RH (TPC2 HOTDOWN ). Venous blood samples and muscle biopsies (vastus lateralis; VL) were obtained before, immediately after, 3, 24, and 48 h after each trial. Leukocyte and VL Hsp72, Hsp90α, and Grp78 mRNA relative expression was determined via RT-QPCR. Attenuated leukocyte and VL Hsp72 (2.8 to 1.8 fold and 5.9 to 2.4 fold; p < 0.05) and Hsp90α mRNA (2.9 to 2.4 fold and 5.2 to 2.4 fold; p < 0.05) responses accompanied reductions ( p < 0.05) in physiological strain [exercising rectal temperature (-0.3°C) and perceived muscle soreness (~ -14%)] during HPC2 HOTDOWN compared to HPC1 HOTDOWN (i.e., a preconditioning effect). Both VL and leukocyte Hsp72 and Hsp90α mRNA increased ( p < 0.05) simultaneously following downhill runs and demonstrated a strong relationship ( p < 0.01) of similar magnitudes with one another. Hot downhill running is an effective preconditioning strategy which ameliorates physiological strain, soreness and Hsp72 and Hsp90α mRNA responses to a subsequent bout. Leukocyte and VL analyses are appropriate tissues to infer the extent to which the HSR has been augmented.

Warm Season Temperatures and Emergency Department Visits in Atlanta, Georgia

PubMed Central

Winquist, Andrea; Grundstein, Andrew; Chang, Howard H.; Hess, Jeremy; Sarnat, Stefanie Ebelt

2016-01-01

Purpose Extreme heat events will likely increase in frequency with climate change. Heat-related health effects are better documented among the elderly than among younger age groups. We assessed associations between warm-season ambient temperature and emergency department (ED) visits across ages in Atlanta during 1993-2012. Methods We examined daily counts of ED visits with primary diagnoses of heat illness, fluid/electrolyte imbalances, renal disease, cardiorespiratory diseases, and intestinal infections by age group (0-4, 5-18, 19-64, 65+ years) in relation to daily maximum temperature (TMX) using Poisson time series models that included cubic terms for TMX at single-day lags of 0-6 days, controlling for maximum dew-point temperature, time trends, week day, holidays, and hospital participation periods. We estimated rate ratios (RRs) and 95% confidence intervals (CI) for TMX changes from 27 °C to 32 °C (25th to 75th percentile) and conducted extensive sensitivity analyses. Results We observed associations between TMX and ED visits for all internal causes, heat illness, fluid/electrolyte imbalances, renal diseases, asthma/wheeze, diabetes, and intestinal infections. Age groups with the strongest observed associations were 65+ years for all internal causes [lag 0 RR (CI)=1.022 (1.016-1.028)] and diabetes [lag 0 RR=1.050 (1.008-1.095)]; 19-64 years for fluid/electrolyte imbalances [lag 0 RR=1.170 (1.136-1.205)] and renal disease [lag 1 RR=1.082 (1.065-1.099)]; and 5-18 years for asthma/wheeze [lag 2 RR=1.059 (1.030-1.088)] and intestinal infections [lag 1 RR=1.120 (1.041-1.205)]. Conclusions Varying strengths of associations between TMX and ED visits by age suggest that optimal interventions and health-impact projections would account for varying heat health impacts across ages. PMID:26922412

Socio-cultural reflections on heat in Australia with implications for health and climate change adaptation

PubMed Central

Banwell, Cathy; Dixon, Jane; Bambrick, Hilary; Edwards, Ferne; Kjellström, Tord

2012-01-01

Background Australia has a hot climate with maximum summer temperatures in its major cities frequently exceeding 35°C. Although ‘heat waves’ are an annual occurrence, the associated heat-related deaths among vulnerable groups, such as older people, suggest that Australians could be better prepared to deal with extreme heat. Objective To understand ways in which a vulnerable sub-population adapt their personal behaviour to cope with heat within the context of Australians’ relationship with heat. Design We draw upon scientific, historical and literary sources and on a set of repeat interviews in the suburbs of Western Sydney with eight older participants and two focus group discussions. We discuss ways in which this group of older people modifies their behaviour to adapt to heat, and reflect on manifestations of Australians’ ambivalence towards heat. Results Participants reported a number of methods for coping with extreme heat, including a number of methods of personal cooling, changing patterns of daily activity and altering dietary habits. The use of air-conditioning was near universal, but with recognition that increasing energy costs may become more prohibitive over time. Conclusions While a number of methods are employed by older people to stay cool, these may become limited in the future. Australians’ attitudes may contribute to the ill-health and mortality associated with excessive heat. PMID:23078748

Vulnerability to extreme heat and climate change: is ethnicity a factor?

PubMed

Hansen, Alana; Bi, Linda; Saniotis, Arthur; Nitschke, Monika

2013-07-29

With a warming climate, it is important to identify sub-populations at risk of harm during extreme heat. Several international studies have reported that individuals from ethnic minorities are at increased risk of heat-related illness, for reasons that are not often discussed. The aim of this article is to investigate the underpinning reasons as to why ethnicity may be associated with susceptibility to extreme heat, and how this may be relevant to Australia's population. Drawing upon literary sources, the authors provide commentary on this important, yet poorly understood area of heat research. Social and economic disparities, living conditions, language barriers, and occupational exposure are among the many factors contributing to heat-susceptibility among minority ethnic groups in the United States. However, there is a knowledge gap about socio-cultural influences on vulnerability in other countries. More research needs to be undertaken to determine the effects of heat on tourists, migrants, and refugees who are confronted with a different climatic environment. Thorough epidemiological investigations of the association between ethnicity and heat-related health outcomes are required, and this could be assisted with better reporting of nationality data in health statistics. Climate change adaptation strategies in Australia and elsewhere need to be ethnically inclusive and cognisant of an upward trend in the proportion of the population who are migrants and refugees.

Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

PubMed

Egan, Kevin; Field, Des; Rea, Mary C; Ross, R Paul; Hill, Colin; Cotter, Paul D

2016-01-01

Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more effectively targeted by bacteriocins in food settings.

High-dose diazepam facilitates core cooling during cold saline infusion in healthy volunteers.

PubMed

Hostler, David; Northington, William E; Callaway, Clifton W

2009-08-01

Studies have suggested that inducing mild hypothermia improves neurologic outcomes after traumatic brain injury, major stroke, cardiac arrest, or exertional heat illness. While infusion of cold normal saline is a simple and inexpensive method for reducing core temperature, human cold-defense mechanisms potentially make this route stressful or ineffective. We hypothesized that intravenous administration of diazepam during a rapid infusion of 30 mL.kg-1 of cold (4 degrees C) 0.9% saline to healthy subjects would be more comfortable and reduce core body temperature more than the administration of cold saline alone. Fifteen subjects received rapidly infused cold (4 degrees C) 0.9% saline. Subjects were randomly assigned to receive, intravenously, 20 mg diazepam (HIGH), 10 mg diazepam (LOW), or placebo (CON). Main outcomes were core temperature, skin temperature, and oxygen consumption. Data for the main outcomes were analyzed with generalized estimating equations to identify differences in group, time, or a group x time interaction. Core temperature decreased in all groups (CON, 1.0 +/- 0.2 degrees C; LOW, 1.4 +/- 0.2 degrees C; HIGH, 1.5 +/- 0.2 degrees C), while skin temperature was unchanged. Mean (95% CI) oxygen consumption was 315.3 (253.8, 376.9) mL.kg-1.min-1 in the CON group, 317.9 (275.5, 360.3) in the LOW group, and 226.1 (216.4, 235.9) in the HIGH group. Significant time and group x time interaction was observed for core temperature and oxygen consumption (p < 0.001). Administration of high-dose diazepam resulted in decreased oxygen consumption during cold saline infusion, suggesting that 20 mg of intravenous diazepam may reduce the shivering threshold without compromising respiratory or cardiovascular function.

Bacteriocins: Novel Solutions to Age Old Spore-Related Problems?

PubMed Central

Egan, Kevin; Field, Des; Rea, Mary C.; Ross, R. Paul; Hill, Colin; Cotter, Paul D.

2016-01-01

Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more effectively targeted by bacteriocins in food settings. PMID:27092121

Prolonged self-paced exercise in the heat – environmental factors affecting performance

PubMed Central

Junge, Nicklas; Jørgensen, Rasmus; Flouris, Andreas D.; Nybo, Lars

2016-01-01

ABSTRACT In this review we examine how self-paced performance is affected by environmental heat stress factors during cycling time trial performance as well as considering the effects of exercise mode and heat acclimatization. Mean power output during prolonged cycling time trials in the heat (≥30°C) was on average reduced by 15% in the 14 studies that fulfilled the inclusion criteria. Ambient temperature per se was a poor predictor of the integrated environmental heat stress and 2 of the prevailing heat stress indices (WBGT and UTCI) failed to predict the environmental influence on performance. The weighing of wind speed appears to be too low for predicting the effect for cycling in trained acclimatized subjects, where performance may be maintained in outdoor time trials at ambient temperatures as high as 36°C (36°C UTCI; 28°C WBGT). Power output during indoor trials may also be maintained with temperatures up to at least 27°C when humidity is modest and wind speed matches the movement speed generated during outdoor cycling, whereas marked reductions are observed when air movement is minimal. For running, representing an exercise mode with lower movement speed and higher heat production for a given metabolic rate, it appears that endurance is affected even at much lower ambient temperatures. On this basis we conclude that environmental heat stress impacts self-paced endurance performance. However, the effect is markedly modified by acclimatization status and exercise mode, as the wind generated by the exercise (movement speed) or the environment (natural or fan air movement) exerts a strong influence. PMID:28090557

Cloud-Radiative Driving of the Madden-Julian Oscillation as Seen by the A-Train

NASA Technical Reports Server (NTRS)

Del Genio, Anthony; Chen, Yonghua

2015-01-01

Cloud and water vapor radiative heating anomalies associated with convection may be an effective source of moist static energy driving the Madden-Julian Oscillation (MJO). In this paper five years of radiative heating profiles derived from CloudSat radar and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation data are analyzed to document radiative heating anomalies during the MJO. Atmospheric shortwave absorption and surface longwave radiation anomalies are of opposite sign and 10-20% as large as top-of-atmosphere outgoing longwave radiation (OLR) anomalies, confirming that OLR provides a useful estimate of the total column radiative heating anomaly. Positive anomalies generally peak about one week before the MJO peak and are smallest over the Indian Ocean. Anomalies over the Maritime Continent are strongest, and coincident with the MJO peak. Shortwave heating profile anomalies are about half as large as longwave anomalies in the active region of the MJO but generally of opposite sign; thus shortwave heating damps the longwave destabilization of the lower troposphere. The exception is the onset phase of the MJO, where shortwave and longwave heating anomalies due to thin cirrus are both positive in the upper troposphere and exert a stabilizing influence. Specific humidity anomalies in the middle troposphere reach 0.5 g kg(exp. -1), but the associated clear sky heating anomaly is very small. Radiative enhancement of column moist static energy becomes significant about 10 days before the MJO peak, when precipitation anomalies are still increasing, and then remains high after the MJO peak after precipitation has begun to decline.

Prospective effect of community distress and subcultural orientation on mortality following life-threatening diseases in later life.

PubMed

Wen, Ming; Christakis, Nicholas A

2006-07-01

We conducted a prospective and contextual study to examine the effects of community social-economic-physical distress and subcultural orientation on mortality following onset of 13 life-threatening diseases in later life. We also examined the inter-relationship between the effects of community social, economic and physical distress (i.e. poverty, physical disorder and low collective efficacy) and subcultural orientation (i.e. anomie and tolerance of risk behaviour) on the survival chances of seriously ill older patients. Three data sources were combined to construct the working sample: 1990 Census data, the 1994-95 PHDCN-CS, and the COSI data. Fifty-one ZIP code areas in Chicago and 12,672 elderly patients were studied. Community distress (HR = 1.04; 95% CI = (1.01, 1.07)) and anomie (HR = 1.26; 95% CI = (1.02, 1.54)) are found to be significantly and positively associated with a higher hazard of death. Moreover, community anomie contributes to the effect of community distress on post-hospitalisation mortality. The social, economic, physical and cultural environment in which people live appears to exert a significant impact on whether older people facing life-threatening illness live or die.

The stress-buffering effects of hope on adjustment to multiple sclerosis.

PubMed

Madan, Sindia; Pakenham, Kenneth I

2014-12-01

Hope is an important resource for coping with chronic illness; however, the role of hope in adjusting to multiple sclerosis (MS) has been neglected, and the mechanisms by which hope exerts beneficial impacts are not well understood. This study aims to examine the direct and stress-moderating effects of dispositional hope and its components (agency and pathways) on adjustment to MS. A total of 296 people with MS completed questionnaires at time 1 at 12 months later and time 2. Focal predictors were stress, hope, agency and pathways, and the adjustment outcomes were anxiety, depression, positive affect, positive states of mind and life satisfaction. Results of regression analyses showed that as predicted, greater hope was associated with better adjustment after controlling for the effects of time 1 adjustment and relevant demographics and illness variables. However, these direct effects of hope were subsumed by stress-buffering effects. Regarding the hope components, the beneficial impacts of agency emerged via a direct effects mechanism, whereas the effects of pathways were evidenced via a moderating mechanism. Findings highlight hope as an important protective coping resource for coping with MS and accentuate the roles of both agency and pathways thinking and their different modes of influence in this process.

Insights into the role of heat shock protein 72 to whole-body heat acclimation in humans

PubMed Central

Amorim, Fabiano Trigueiro; Fonseca, Ivana T; Machado-Moreira, Christiano A; Magalhães, Flávio de Castro

2015-01-01

Abstract Heat acclimation results in systemic and cellular adaptions that reduce the negative effect of heat and, consequently, the risk of heat illness. Although the classical changes observed with heat acclimation lead to increased tolerance to exercise in the heat by reducing heat storage (reflected in reduced core and skin temperatures) and increasing whole-body capacity for heat dissipation (greater plasma volume, sweat output, and skin blood flow), it appears that heat acclimation also induces changes at the cellular level that might increase tolerance of the whole organism to a higher core temperature for the development of fatigue. Thermotolerance is a process that involves increased resilience to an otherwise lethal heat stress that follows a sublethal exposure to heat. Thermotolerance is believed to be the result of increased content of heat shock proteins (Hsp), specially a member of the 70 kDa family, Hsp72 kDa. In humans, we and others have reported that heat acclimation increases intracellular Hsp72 levels. This increase in intracellular Hsp72 could improve whole-body organism thermotolerance by maintaining intestinal epithelial tight junction barriers, by increasing resistance to gut-associated endotoxin translocation, or by reducing the inflammatory response. In this review, we will initially provide an overview of the physiological adaptations induced by heat acclimation and emphasize the main cellular changes that occur with heat acclimation associated with intracellular accumulation of Hsp72. Finally, we will present an argument for a role of whole-body heat acclimation in augmenting cellular thermotolerance, which may protect vital organs from deleterious effects of heat stress in humans. PMID:27227070

Caloric restriction induces heat shock response and inhibits B16F10 cell tumorigenesis both in vitro and in vivo.

PubMed

Novelle, Marta G; Davis, Ashley; Price, Nathan L; Ali, Ahmed; Fürer-Galvan, Stefanie; Zhang, Yongqing; Becker, Kevin; Bernier, Michel; de Cabo, Rafael

2015-04-01

Caloric restriction (CR) without malnutrition is one of the most consistent strategies for increasing mean and maximal lifespan and delaying the onset of age-associated diseases. Stress resistance is a common trait of many long-lived mutants and life-extending interventions, including CR. Indeed, better protection against heat shock and other genotoxic insults have helped explain the pro-survival properties of CR. In this study, both in vitro and in vivo responses to heat shock were investigated using two different models of CR. Murine B16F10 melanoma cells treated with serum from CR-fed rats showed lower proliferation, increased tolerance to heat shock and enhanced HSP-70 expression, compared to serum from ad libitum-fed animals. Similar effects were observed in B16F10 cells implanted subcutaneously in male C57BL/6 mice subjected to CR. Microarray analysis identified a number of genes and pathways whose expression profile were similar in both models. These results suggest that the use of an in vitro model could be a good alternative to study the mechanisms by which CR exerts its anti-tumorigenic effects.

Caloric restriction induces heat shock response and inhibits B16F10 cell tumorigenesis both in vitro and in vivo

PubMed Central

Novelle, Marta G.; Davis, Ashley; Price, Nathan L.; Ali, Ahmed; Fürer-Galvan, Stefanie; Zhang, Yongqing; Becker, Kevin; Bernier, Michel; de Cabo, Rafael

2015-01-01

Caloric restriction (CR) without malnutrition is one of the most consistent strategies for increasing mean and maximal lifespan and delaying the onset of age-associated diseases. Stress resistance is a common trait of many long-lived mutants and life-extending interventions, including CR. Indeed, better protection against heat shock and other genotoxic insults have helped explain the pro-survival properties of CR. In this study, both in vitro and in vivo responses to heat shock were investigated using two different models of CR. Murine B16F10 melanoma cells treated with serum from CR-fed rats showed lower proliferation, increased tolerance to heat shock and enhanced HSP-70 expression, compared to serum from ad libitum-fed animals. Similar effects were observed in B16F10 cells implanted subcutaneously in male C57BL/6 mice subjected to CR. Microarray analysis identified a number of genes and pathways whose expression profile were similar in both models. These results suggest that the use of an in vitro model could be a good alternative to study the mechanisms by which CR exerts its anti-tumorigenic effects. PMID:25948793

Rubber friction: role of the flash temperature

NASA Astrophysics Data System (ADS)

Persson, B. N. J.

2006-08-01

When a rubber block is sliding on a hard rough substrate, the substrate asperities will exert time-dependent deformations of the rubber surface resulting in viscoelastic energy dissipation in the rubber, which gives a contribution to the sliding friction. Most surfaces of solids have roughness on many different length scales, and when calculating the friction force it is necessary to include the viscoelastic deformations on all length scales. The energy dissipation will result in local heating of the rubber. Since the viscoelastic properties of rubber-like materials are extremely strongly temperature dependent, it is necessary to include the local temperature increase in the analysis. At very low sliding velocity the temperature increase is negligible because of heat diffusion, but already for velocities of order 10-2 m s-1 the local heating may be very important. Here I study the influence of the local heating on the rubber friction, and I show that in a typical case the temperature increase results in a decrease in rubber friction with increasing sliding velocity for v>0.01 m s-1. This may result in stick-slip instabilities, and is of crucial importance in many practical applications, e.g. for tyre-road friction and in particular for ABS braking systems.

Dancing to death: A case of heat stroke.

PubMed

Nadesan, K; Kumari, Chandra; Afiq, Mohd

2017-08-01

Heat stroke is a medical emergency which may lead to mortality unless diagnosed early and treated effectively. Heat stroke may manifest rapidly, hence making it difficult to differentiate it from other clinical causes in a collapsed victim. 1 We are presenting a case report of twelve patients who were admitted to our emergency department from a music festival held on 13-15th of March 2014. They developed complications arising from a combination of severe adverse weather condition, prolonged outdoor physical exertion due to long hours of dancing and drug-use, resulting in heat stroke. Three of them died while the remaining patients survived. Their condition was initially misdiagnosed as a classical illicit drug overdose. This was based on the history of drug ingestion by some of the patients who attended the music festival on that day. The information in this case report aims, to create awareness amongst members of the medical team on duty in outdoor events, pre hospital responders and ED physicians when treating and managing similar cases in the future. In addition it is intended to warn the organizers of such events to take adequate precautions to avoid such tragedies in the future. Copyright © 2017. Published by Elsevier Ltd.

Influence of Two-Phase Thermocapillary Flow on Cryogenic Liquid Retention in Microscopic Pores

NASA Technical Reports Server (NTRS)

Schmidt, G. R.; Nadarajah, A.; Chung, T. J.; Karr, G. R.

1994-01-01

Previous experiments indicate that the bubble point pressure of spacecraft liquid hydrogen acquisition devices is reduced substantially when the ullage is pressurized with heated hydrogen vapor. The objective is to determine whether the two-phase thermocapillary convection arising from thermodynamic non-equilibrium along the porous surfaces of such devices could lead to this observed degradation in retention performance. We also examine why retention capability appears to be unaffected by pressurization with heated helium or direct heating through the porous structure. Computational assessments based on coupled solution of the flowfield and liquid free surface indicate that for highly wetting fluids in small pores, dynamic pressure and vapor recoil dictate surface morphology and drive meniscus deformation. With superheating, the two terms exert the same influence on curvature and promote mechanical equilibrium, but with subcooling, the pressure distribution produces a suction about the pore center-line that degrades retention. This result points to thermocapillary-induced deformation arising from condensation as the cause for retention loss. It also indicates that increasing the level of non-equilibrium by reducing accommodation coefficient restricts deformation and explains why retention failure does not occur with direct screen heating or helium pressurization.

Retrieved Latent Heating from TRMM

NASA Technical Reports Server (NTRS)

Tao, Wei-Kuo; Smith, Eric A.; Houze Jr, Robert

2008-01-01

The global hydrological cycle is central to the Earth's climate system, with rainfall and the physics of precipitation formation acting as the key links in the cycle. Two-thirds of global rainfall occurs in the tropics with the associated latent heating (LH) accounting for three-fourths of the total heat energy available to the Earth's atmosphere. In addition, fresh water provided by tropical rainfall and its variability exerts a large impact upon the structure and motions of the upper ocean layer. In the last decade, it has been established that standard products of LH from satellite measurements, particularly TRMM measurements, would be a valuable resource for scientific research and applications. Such products would enable new insights and investigations concerning the complexities of convection system life cycles, the diabatic heating controls and feedbacks related to meso-synoptic circulations and their forecasting, the relationship of tropical patterns of LH to the global circulation and climate, and strategies for improving cloud parameterizations in environmental prediction models. The status of retrieved TRMM LH products, TRMM LH inter-comparison and validation project, current TRMM LH applications and critic issues/action items (based on previous five TRMM LH workshops) is presented in this article.

Bovine milk fat globule membrane affects virulence expression in Escherichia coli O157:H7.

PubMed

Tellez, A; Corredig, M; Guri, A; Zanabria, R; Griffiths, M W; Delcenserie, V

2012-11-01

The aim of this study was to examine the effect of the bovine milk fat globule membrane (MFGM) on the virulence of Escherichia coli O157:H7. The MFGM was extracted from raw or heat-treated milk, resulting in 2 preparations differing in protein composition. Both heated and raw MFGM exerted an inhibitory effect on Shiga toxin gene expression by E. coli O157:H7 (ratios of -7.69 and -5.96, respectively). Interestingly, the effect was stronger with heated MFGM, with a larger decrease in expression of the virulence gene fliC (ratio of -9.43). The difference in effect observed between heated and raw MFGM could be explained by the difference in protein composition between the 2 preparations. These results show, for the first time, a specific effect of MFGM on expressionof Shiga toxin genes as well as genes involved in the motility of E. coli O157:H7. This may offer a new approach to mitigate the adverse health effects caused by E. coli O157:H7 infections. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of drop size on the impact thermodynamics for supercooled large droplet in aircraft icing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Chen; Liu, Hong, E-mail: hongliu@sjtu.edu.cn

Supercooled large droplet (SLD), which can cause abnormal icing, is a well-known issue in aerospace engineering. Although efforts have been exerted to understand large droplet impact dynamics and the supercooled feature in the film/substrate interface, respectively, the thermodynamic effect during the SLD impact process has not received sufficient attention. This work conducts experimental studies to determine the effects of drop size on the thermodynamics for supercooled large droplet impingement. Through phenomenological reproduction, the rapid-freezing characteristics are observed in diameters of 400, 800, and 1300 μm. The experimental analysis provides information on the maximum spreading rate and the shrinkage rate ofmore » the drop, the supercooled diffusive rate, and the freezing time. A physical explanation of this unsteady heat transfer process is proposed theoretically, which indicates that the drop size is a critical factor influencing the supercooled heat exchange and effective heat transfer duration between the film/substrate interface. On the basis of the present experimental data and theoretical analysis, an impinging heating model is developed and applied to typical SLD cases. The model behaves as anticipated, which underlines the wide applicability to SLD icing problems in related fields.« less

Stress Proteins and Initiation of Immune Response: Chaperokine activity of Hsp72

PubMed Central

Asea, Alexzander

2006-01-01

From its original description as solely an intracellular molecular chaperone, heat shock proteins have now been shown to function as initiators of the host's immune response. Although the exact mechanism by which intracellular heat shock proteins leave cells is still incompletely understood, recent work from several labs suggest that heat shock proteins are released by both passive (necrotic) and active (physiological) mechanisms. Binding to specific surface receptors is a prerequisite for the initiation of an immune response. To date, several cell surface proteins have been described as the receptor for seventy kilo-Dalton heat shock protein (Hsp70) including Toll-like receptors 2 and 4 with their cofactor CD14, the scavenger receptor CD36, the low-density lipoprotein receptor-related protein CD91, the C-type lectin receptor LOX-1, and another member of the scavenger super-family SR-A plus the co-stimulatory molecule, CD40. Binding of Hsp70 to these surface receptors specifically activates intracellular signaling cascades, which in turn exert immunoregulatory effector functions; a process known as the chaperokine activity of Hsp70. This review will highlight recent advances in understanding the mechanism by which Hsp70 initiates the host's immune response. PMID:16385842

Stress proteins and initiation of immune response: chaperokine activity of hsp72.

PubMed

Asea, Alexzander

2005-01-01

From its original description as solely an intracellular molecular chaperone, heat shock proteins have now been shown to function as initiators of the host's immune response. Although the exact mechanism by which intracellular heat shock proteins leave cells is still incompletely understood, recent work from several labs suggest that heat shock proteins are released by both passive (necrotic) and active (physiological) mechanisms. Binding to specific surface receptors is a prerequisite for the initiation of an immune response. To date, several cell surface proteins have been described as the receptor for seventy kilo-Dalton heat shock protein (Hsp70) including Toll-like receptors 2 and 4 with their cofactor CD14, the scavenger receptor CD36, the low-density lipoprotein receptor-related protein CD91, the C-type lectin receptor LOX-1, and another member of the scavenger super-family SR-A plus the co-stimulatory molecule, CD40. Binding of Hsp70 to these surface receptors specifically activates intracellular signaling cascades, which in turn exert immunoregulatory effector functions; a process known as the chaperokine activity of Hsp70. This review will highlight recent advances in understanding the mechanism by which Hsp70 initiates the host's immune response.

Weather and environmental hazards at mass gatherings.

PubMed

Soomaroo, Lee; Murray, Virginia

2012-07-31

Introduction Reviews of mass gathering events have traditionally concentrated on crowd variables that affect the level and type of medical care needed. Weather and environmental hazards at mass gathering events have not been fully researched. This review examines these events and aims to provide future suggestions for event organisers, medical resource planners, and emergency services, including local hospital emergency departments. Methods A review was conducted using computerised data bases: MEDLINE, The Cochrane Library, HMIC and EMBASE, with Google used to widen the search beyond peer-reviewed publications, to identify grey literature. All peer-review literature articles found containing information pertaining to lessons identified from mass gathering disasters due to weather or environmental hazards leading to participant death, injury or illness were analysed and reviewed. Disasters occurring due to crowd variables were not included. These articles were read, analysed, abstracted and summarised. Results 20 articles from literature search were found detailing mass gathering disasters relating directly to weather or environmental hazards from 1988 - 2011, with only 17 cases found within peer-review literature. Two events grey literature from 2011 are due to undergo further inquiry while one article reviews an event originally occurring in 1922. Analysis of cases were categorised in to heat and cold-related events, lightning and storms and disease outbreak. Conclusions Mass gathering events have an enormous potential to place a severe strain on the local health care system, Prior health resource and environmental planning for heat & cold-related illness, lightning & storms, and disease outbreak can advance emergency preparedness and response to potential disasters. Soomaroo L, Murray V. Weather and Environmental Hazards at Mass Gatherings. PLoS Currents Disasters. 2012 Jul 31 KEYWORDS: Mass Gatherings, Disasters, Sporting Events, Festivals, Concerts, Storm, Lightning, Cyclone, Hot-weather illness, Cold-weather illness, Disease, Public Health, Syndromic Surveillance Abbreviations: ALS - Advance Life support; BLS - Basic Life support; ED - Emergency Department; EMS - Emergency Medical Services; PPR - Patient Presentation Rate.

Weather and Environmental Hazards at Mass Gatherings

PubMed Central

Soomaroo, Lee; Murray, Virginia

2012-01-01

Introduction Reviews of mass gathering events have traditionally concentrated on crowd variables that affect the level and type of medical care needed. Weather and environmental hazards at mass gathering events have not been fully researched. This review examines these events and aims to provide future suggestions for event organisers, medical resource planners, and emergency services, including local hospital emergency departments. Methods A review was conducted using computerised data bases: MEDLINE, The Cochrane Library, HMIC and EMBASE, with Google used to widen the search beyond peer-reviewed publications, to identify grey literature. All peer-review literature articles found containing information pertaining to lessons identified from mass gathering disasters due to weather or environmental hazards leading to participant death, injury or illness were analysed and reviewed. Disasters occurring due to crowd variables were not included. These articles were read, analysed, abstracted and summarised. Results 20 articles from literature search were found detailing mass gathering disasters relating directly to weather or environmental hazards from 1988 – 2011, with only 17 cases found within peer-review literature. Two events grey literature from 2011 are due to undergo further inquiry while one article reviews an event originally occurring in 1922. Analysis of cases were categorised in to heat and cold-related events, lightning and storms and disease outbreak. Conclusions Mass gathering events have an enormous potential to place a severe strain on the local health care system, Prior health resource and environmental planning for heat & cold-related illness, lightning & storms, and disease outbreak can advance emergency preparedness and response to potential disasters. Citation: Soomaroo L, Murray V. Weather and Environmental Hazards at Mass Gatherings. PLoS Currents Disasters. 2012 Jul 31 Keywords: Mass Gatherings, Disasters, Sporting Events, Festivals, Concerts, Storm, Lightning, Cyclone, Hot-weather illness, Cold-weather illness, Disease, Public Health, Syndromic Surveillance Abbreviations: ALS – Advance Life support; BLS – Basic Life support; ED – Emergency Department; EMS – Emergency Medical Services; PPR – Patient Presentation Rate PMID:22953242

Imagining intergroup contact can combat mental health stigma by reducing anxiety, avoidance and negative stereotyping.

PubMed

Stathi, Sofia; Tsantila, Katerina; Crisp, Richard J

2012-01-01

Research has demonstrated widespread negative attitudes held toward people with mental health problems. Our study investigated whether a new prejudice reduction technique, imagined intergroup contact (Crisp & Turner, 2009), could combat stigma against people with mental illness, and the mediating processes through which it may exert this beneficial effect. We found that compared to a control condition, participants who imagined a positive encounter with a schizophrenic person reported weakened stereotypes and formed stronger intentions to engage in future social interactions with schizophrenic people in general. Importantly, these intentions were formed due to reduced feelings of anxiety about future interactions. We discuss the implications of these findings for improving the social inclusion of people with mental health problems.

Very rapid enhancement by D$sub 2$O of the temperature-tolerance of adult Drosophila

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pittendrigh, C.S.; Cosbey, E.S.

1974-02-01

Deuterium oxide, D/sub 2/O, increases the temperature-tolerance of Drosophila pseudoobscura when it is administered to adult flies as a sucrose solution. The effect is very rapidly exerted; it is detected within 10 min after the flies have a brief (10 min) opportunity to drink. This increased resistance to heat-death surely implies an increased resistence of macromolecules to thermal denaturation. D/sub 2/O is known to exert such an effect on in vitro protein solutions. The speed with which the increased stability develops clearly implicates a solvent action of D/sub 2/O, and is most easily understoed if the effect is traceable tomore » enhancement of the hydrophobic interactions which contribute to conformational stability. The increased strength of deuterated hydrogen bonds cannot be excluded however. The possible bearing of these results on the hypothesis that D/sub 2/O always increases the period of circadian oscillations by diminishing the apparent temperature'' is briefly considered. (auth)« less

The prozone effect exerted by the complement-binding anti-Lea on anti-D.

PubMed

Joshi, Sanmukh R; Parekh, Kamlesh H

2017-01-01

Prozone phenomenon is seen with very high-titer antibodies in an immune serum. The prozone effect on anti-D by a low-titer anti-Le a was investigated associated with neonatal jaundice. Standard methods were used in investigations. The child was born at full-term developed mild jaundice. With weak direct antiglobulin test+, her indirect serum bilirubin was progressed to 27.5 mg/dL in 48 h. Anti-D and anti-Le a were detected in the mother. Both these antibodies were detected in the child's serum though the eluate from red blood cells (RBCs) contained only anti-D. Mother's anti-D was masked by anti-Le a if the RBCs possessed both the antigens together. Anti-D was revealed only with D-positive RBCs lacking Le a or if the serum was modified by mixing with Le a+ saliva or was heated at 56°C or fortified with citrate solution. An anti-D showed prozone effect exerted by the complement-fixing anti-Le a in the test.

Determination of future prevention strategies in elite track and field: analysis of Daegu 2011 IAAF Championships injuries and illnesses surveillance

PubMed Central

Alonso, Juan-Manuel; Edouard, Pascal; Fischetto, Giuseppe; Adams, Bob; Depiesse, Frédéric; Mountjoy, Margo

2012-01-01

Objective To determine the incidence and characteristics of newly incurred injuries and illnesses during international Athletics Championships, by improving the medical surveillance coverage, in order to determine future prevention strategies. Design Prospective recording of newly occurred injuries and illnesses. Setting 13th International Association of Athletics Federations World Championships in Athletics 2011 in Daegu, Korea. Participants National team and Local Organising Committee physicians; and 1851 registered athletes. Main outcome measures Incidence and characteristics of newly incurred injuries and illnesses. Results 82% of athletes were covered by medical teams participating with a response rate of 94%. A total of 249 injuries were reported, representing an incidence of 134.5 injuries per 1000 registered athletes, and 119 (48%) resulted in time loss from sport. A total of 185 injuries affected the lower limb (74%). Hamstring strain was the main diagnosis and 67% resulted in absence from sport. Overuse (n=148; 59%) was the predominant cause. A total of 126 illnesses were reported, signifying an incidence of 68.1 per 1000 registered athletes. Upper respiratory tract infection was the most common reported diagnosis (18%), followed by exercise-induced dehydration (12%), and gastroenteritis/diarrhoea (10%). The highest incidences of injuries were found in combined events and middle and long-distance events, and of illness in race walking events. Conclusion During elite Athletics World Championships, 135 injuries, 60 time-loss injuries and 68 illnesses per 1000 registered athletes were reported. Higher risks of injuries were found in combined events and long-distance runs. Preventive interventions should focus on overuse injuries and hamstring strains, decreasing the risk of transmission of infectious diseases, appropriate event scheduling and heat acclimatisation. PMID:22522588

Occupational hazards and illnesses of Filipino women workers in export processing zones.

PubMed

Lu, Jinky Leilanie

2008-01-01

This was a baseline study on occupational exposure and health problems among women workers in export processing zones. Physical, chemical, and ergonomic hazards were evaluated and measured through workplace ambient monitoring, survey questionnaires, and interviews with 500 respondents in 24 companies (most were female at 88.8%). The top 5 hazards were ergonomic hazards (72.2%), heat (66.6%), overwork (66.6%), poor ventilation (54.8%), and chemical exposure (50.8%). The most common illnesses were gastrointestinal problems (57.4%), backache (56%), headache (53.2%), and fatigue/weakness (53.2%). Logistic regression showed an association between certain work-related factors and occupational illnesses, and psychosocial problems. Highly significant associations were hearing loss with years spent in the company (p=.005) and gender (p=.006), headache and dizziness with poor ventilation (p=.000), backache with prolonged work (p=.003). These results will have implications for policy and program formulation for women workers' concerns and issues in export zones.

Metabolic Rate and Perceived Exertion of Walking in Older Adults With Idiopathic Chronic Fatigue

PubMed Central

Corbett, Duane B.; Knaggs, Jeffrey D.; Manini, Todd M.

2016-01-01

Abstract Background: Fatigue is a common complaint in older adults, often not associated with underlying medical conditions. The purpose of this study was to investigate metabolic rate (MR) of walking, walking performance, and perception-based exertion during walking in older adults with and without idiopathic chronic fatigue (ICF). Methods: 20 older adults (aged 70.8±4.9 years), reporting 2 SD above normative values of the Functional Assessment of Chronic Illness Therapy-Fatigue scale and without overt health conditions that explained their symptoms, were compared with 25 age-matched older adults (73.2±5.1 years) without fatigue symptoms. Participants walked 400 m at a rapid pace on a 20-m course. On a separate visit, oxygen consumption was measured during treadmill test at standard (40.2 m/min), preferred paces (40–83 m/min) and peak capacity. Ratings of perceived exertion (RPE) were measured at each treadmill stage and after each lap of the 400-m walk test. Results: During the 400-m walk test, individuals with ICF showed lower overall walking speed and reported a steady increase in RPE with no change observed in non-fatigued group (1.63±1.72 vs 0.27±0.68, p < .01). Similar findings on RPE were noted on treadmill test. Gross MR, mass-specific MR, mass-specific net MR, and MR as a percent of peak oxygen consumption of walking were similar between groups during standard, preferred paces and peak capacity on treadmill. Conclusions: This study suggests that ICF in older adults is not related to elevated metabolic cost of walking. Higher RPE without concomitant decreases in performance indicate a potential disconnect between metabolic output and sensations during movement. PMID:27271253

Effects of heat acclimation on time perception.

PubMed

Tamm, Maria; Jakobson, Ainika; Havik, Merle; Timpmann, Saima; Burk, Andres; Ööpik, Vahur; Allik, Jüri; Kreegipuu, Kairi

2015-03-01

Cognitive performance is impaired during prolonged exercise in hot environment compared to temperate conditions. These effects are related to both peripheral markers of heats stress and alterations in CNS functioning. Repeated-exposure to heat stress results in physiological adaptations, and therefore improvement in exercise capacity and cognitive functioning are observed. The objective of the current study was to clarify the factors contributing to time perception under heat stress and examine the effect of heat acclimation. 20 young healthy male subjects completed three exercise tests on a treadmill: H1 (at 60% VO(2)peak until exhaustion at 42°C), N (at 22°C; duration equal to H1) and H2 (walk until exhaustion at 42°C) following a 10-day heat acclimation program. Core temperature (T(C)) and heart rate (HR), ratings of perceived fatigue and exertion were obtained continuously during the exercise, and blood samples of hormones were taken before, during and after the exercise test for estimating the prolactin, growth hormone and cortisol response to acute exercise-heat stress. Interval production task was performed before, during and after the exercise test. Lower rate of rise in core temperature, heart rate, hormone response and subjective ratings indicated that the subjects had successfully acclimated. Before heat acclimation, significant distortions in produced intervals occurred after 60 minutes of exercise relative to pre-trial coefficients, indicating speeded temporal processing. However, this effect was absent after in acclimated subjects. Blood prolactin concentration predicted temporal performance in both conditions. Heat acclimation slows down the increase in physiological measures, and improvement in temporal processing is also evident. The results are explained within the internal clock model in terms of the pacemaker-accumulator functioning. Copyright © 2014 Elsevier B.V. All rights reserved.

Intraosseous heat generation during sonic, ultrasonic and conventional osteotomy.

PubMed

Rashad, Ashkan; Sadr-Eshkevari, Pooyan; Heiland, Max; Smeets, Ralf; Hanken, Henning; Gröbe, Alexander; Assaf, Alexandre T; Köhnke, Robert H; Mehryar, Pouyan; Riecke, Björn; Wikner, Johannes

2015-09-01

To assess heat generation in osteotomies during application of sonic and ultrasonic saws compared to conventional bur. Two glass-fiber isolated nickel-chromium thermocouples, connected to a recording device, were inserted into fresh bovine rib bone blocks and kept in 20 ± 0.5 °C water at determined depths of 1.5 mm (cortical layer) and 7 mm (cancellous layer) and 1.0 mm away from the planned osteotomy site. Handpieces, angulated 24-32°, were mounted in a vertical drill stand, and standardized weights were attached to their tops to exert loads of 5, 8, 15 and 20 N. Irrigation volumes of 20, 50 and 80 ml/min were used for each load. Ten repetitions were conducted using new tips each time for each test condition. The Mann-Whitney-U test was used for statistical analysis (p < 0.05). Both ultrasonic and sonic osteotomies were associated with significantly lower heat generation than conventional osteotomy (p < 0.01). Sonic osteotomy showed non-significantly lower heat generation than ultrasonic osteotomy. Generated heat never exceeded the critical limit of 47 °C in any system. Variation of load had no effect on heat generation in both bone layers for all tested systems. An increased irrigation volume resulted in lower temperatures in both cortical and cancellous bone layers during all tested osteotomies. Although none of the systems under the conditions of the present study resulted in critical heat generation, the application of ultrasonic and sonic osteotomy systems was associated with lower heat generation compared to the conventional saw osteotomy. Copious irrigation seems to play a critical role in preventing heat generation in the osteotomy site. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Heat: not black, not white. It's gray!!!

PubMed

Singh, Laxmi Prabha; Kapoor, Medha; Singh, Shashi Bala

2013-01-01

Heat-related illness (HRI) is a broad term that includes clinical conditions ranging from heat cramps and syncope to heat exhaustion and heatstroke, which may result in death. HRIs are one of the major causes of death worldwide and continue to increase in severity with the rise in global temperature. The identification and estimation of heat-related morbidity and mortality is a major challenge. Heat stress manifests itself into respiratory, cardiovascular, and cerebrovascular disorders, leading to the attribution of the deaths caused by heat stress to these disorders. Although HRIs affect mankind in general, certain occupational workers such as soldiers and athletes are more prone. Various pharmacological and nonpharmacological strategies have been employed to combat HRIs. Despite this, heat exposure results in significant morbidity and mortality. Hence, complete understanding of HRIs at physiological as well as molecular level is required to facilitate design of more efficient preventive and treatment strategies. The impact of heat on mankind is not just restricted to HRIs. Heat treatment, i.e., thermotherapy, has been used extensively since ancient times for relieving pain, making heat a two-edged sword. This review attempts to summarize various HRIs, their physiological and molecular basis, and the state-of-the-art techniques/research initiatives to combat the same. It also illustrates the application of thermotherapy as a means for improving quality of life and morbidity associated with several disease conditions such as fibromyalgia syndrome, heart diseases, cancer, chronic pain, and depression.

Characterizing open and non-uniform vertical heat sources: towards the identification of real vertical cracks in vibrothermography experiments

NASA Astrophysics Data System (ADS)

Castelo, A.; Mendioroz, A.; Celorrio, R.; Salazar, A.; López de Uralde, P.; Gorosmendi, I.; Gorostegui-Colinas, E.

2017-05-01

Lock-in vibrothermography is used to characterize vertical kissing and open cracks in metals. In this technique the crack heats up during ultrasound excitation due mainly to friction between the defect's faces. We have solved the inverse problem, consisting in determining the heat source distribution produced at cracks under amplitude modulated ultrasound excitation, which is an ill-posed inverse problem. As a consequence the minimization of the residual is unstable. We have stabilized the algorithm introducing a penalty term based on Total Variation functional. In the inversion, we combine amplitude and phase surface temperature data obtained at several modulation frequencies. Inversions of synthetic data with added noise indicate that compact heat sources are characterized accurately and that the particular upper contours can be retrieved for shallow heat sources. The overall shape of open and homogeneous semicircular strip-shaped heat sources representing open half-penny cracks can also be retrieved but the reconstruction of the deeper end of the heat source loses contrast. Angle-, radius- and depth-dependent inhomogeneous heat flux distributions within these semicircular strips can also be qualitatively characterized. Reconstructions of experimental data taken on samples containing calibrated heat sources confirm the predictions from reconstructions of synthetic data. We also present inversions of experimental data obtained from a real welded Inconel 718 specimen. The results are in good qualitative agreement with the results of liquids penetrants testing.

Forcings and feedbacks by land ecosystem changes on climate change

NASA Astrophysics Data System (ADS)

Betts, R. A.

2006-12-01

Vegetation change is involved in climate change through both forcing and feedback processes. Emissions of CO{2} from past net deforestation are estimated to have contributed approximately 0.22 0.51 Wm - 2 to the overall 1.46 Wm - 2 radiative forcing by anthropogenic increases in CO{2} up to the year 2000. Deforestation-induced increases in global mean surface albedo are estimated to exert a radiative forcing of 0 to -0.2 Wm - 2, and dust emissions from land use may exert a radiative forcing of between approximately +0.1 and -0.2 Wm - 2. Changes in the fluxes of latent and sensible heat due to tropical deforestation are simulated to have exerted other local warming effects which cannot be quantified in terms of a Wm - 2 radiative forcing, with the potential for remote effects through changes in atmospheric circulation. With tropical deforestation continuing rapidly, radiative forcing by surface albedo change may become less useful as a measure of the forcing of climate change by changes in the physical properties of the land surface. Although net global deforestation is continuing, future scenarios used for climate change prediction suggest that fossil fuel emissions of CO{2} may continue to increase at a greater rate than land use emissions and therefore continue to increase in dominance as the main radiative forcing. The CO{2} rise may be accelerated by up to 66% by feedbacks arising from global soil carbon loss and forest dieback in Amazonia as a consequence of climate change, and Amazon forest dieback may also exert feedbacks through changes in the local water cycle and increases in dust emissions.

Metoprolol vs ivabradine in patients with mitral stenosis in sinus rhythm.

PubMed

Agrawal, Vikas; Kumar, Niraj; Lohiya, Balalji; Sihag, Bhupendra K; Prajapati, Rajpal; Singh, T B; Subramanian, Geetha

2016-10-15

Severe mitral stenosis is usually symptomatic and is treated by BMV or surgery, whereas mild to moderate mitral stenosis is usually asymptomatic or mildly symptomatic and managed medically. Patients in the later group may become symptomatic during episodes of exercise and increased heart rate. Beta-blockers are frequently used in patients with mitral stenosis to control the heart rate and alleviate exercise-related symptoms. The objective of our study was to investigate the comparative efficacy of ivabradine versus metoprolol in patients with mitral stenosis in sinus rhythm. We studied 97 patients of mitral stenosis in sinus rhythm presented with exertional symptoms. The effectiveness of Metoprolol was compared with ivabradine in alleviating these exertional symptoms in a randomized, open label non crossover study. We also assessed various stress ECG parameters, 24 hour Holter parameters and 2D Echo parameters to objectively compare the effects of ivabradine and metoprolol in these patients. Ivabradine and metoprolol both were effective in controlling exertional symptoms. Significant improvement in objective parameters like TMT (work capacity, baseline heart rate and maximal heart rate) and 2D echocardiography (right ventricular systolic pressure) are seen with both drugs. Ivabradine controls the exertional symptoms significantly more than metoprolol. On head to head comparison there was a significant benefit of working capacity and heart rate at maximal exercise in favour of ivabradine. Ivabradine should be strongly considered in medical management of mitral stenosis patients where beta blockers are contraindicated such as reactive airway disease. The cost of ivabradine is higher than metoprolol which might possess constraints as most of the rheumatic heat disease patients belong to low socio economic status. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Promoting Protection Against a Threat That Evokes Positive Affect: The Case of Heat Waves in the United Kingdom

PubMed Central

2016-01-01

Heat waves can cause death, illness, and discomfort, and are expected to become more frequent as a result of climate change. Yet, United Kingdom residents have positive feelings about hot summers that may undermine their willingness to protect themselves against heat. We randomly assigned United Kingdom participants to 1 of 3 intervention strategies intended to promote heat protection, or to a control group. The first strategy aimed to build on the availability heuristic by asking participants to remember high summer temperatures, but it elicited thoughts of pleasantly hot summer weather. The second strategy aimed to build on the affect heuristic by evoking negative affect about summer temperatures, but it evoked thoughts of unpleasantly cold summer weather. The third strategy combined these 2 approaches and succeeded in evoking thoughts of unpleasantly hot summer weather. Across 2 experiments, the third (combined) strategy increased participants’ expressed intentions to protect against heat compared with the control group, while performing at least as well as the 2 component strategies. We discuss implications for developing interventions about other “pleasant hazards.” PMID:27268282

Advancing the Use of Emergency Department Syndromic Surveillance Data, New York City, 2012-2016.

PubMed

Lall, Ramona; Abdelnabi, Jasmine; Ngai, Stephanie; Parton, Hilary B; Saunders, Kelly; Sell, Jessica; Wahnich, Amanda; Weiss, Don; Mathes, Robert W

The use of syndromic surveillance has expanded from its initial purpose of bioterrorism detection. We present 6 use cases from New York City that demonstrate the value of syndromic surveillance for public health response and decision making across a broad range of health outcomes: synthetic cannabinoid drug use, heat-related illness, suspected meningococcal disease, medical needs after severe weather, asthma exacerbation after a building collapse, and Ebola-like illness in travelers returning from West Africa. The New York City syndromic surveillance system receives data on patient visits from all emergency departments (EDs) in the city. The data are used to assign syndrome categories based on the chief complaint and discharge diagnosis, and analytic methods are used to monitor geographic and temporal trends and detect clusters. For all 6 use cases, syndromic surveillance using ED data provided actionable information. Syndromic surveillance helped detect a rise in synthetic cannabinoid-related ED visits, prompting a public health investigation and action. Surveillance of heat-related illness indicated increasing health effects of severe weather and led to more urgent public health messaging. Surveillance of meningitis-related ED visits helped identify unreported cases of culture-negative meningococcal disease. Syndromic surveillance also proved useful for assessing a surge of methadone-related ED visits after Superstorm Sandy, provided reassurance of no localized increases in asthma after a building collapse, and augmented traditional disease reporting during the West African Ebola outbreak. Sharing syndromic surveillance use cases can foster new ideas and build capacity for public health preparedness and response.

The impact of heatwaves on workers' health and safety in Adelaide, South Australia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiang, Jianjun; Bi, Peng, E-mail: peng.bi@adelaide.edu.au; Pisaniello, Dino

This study aims to investigate the impact of heatwaves on worker's health and safety; to identify workers at higher risk of prevalent illnesses and injuries due to heatwaves; and to provide evidence for policy-makers and service providers. South Australian workers' compensation claims data for 2001–2010 were transformed into time series format, merged with meteorological data and analysed using generalized estimating equation (GEE) models. For total injury claims there was no significant difference detected between heatwave and non-heatwave periods. However, for outdoor industries, daily claims increased significantly by 6.2% during heatwaves. Over-represented in hot weather were male labourers and tradespersons agedmore » ≥55 years, and those employed in ‘agriculture, forestry and fishing’ and ‘electricity, gas and water’. Occupational burns, wounds, lacerations, and amputations as well as heat illnesses were significantly associated with heatwaves. Similarly, moving objects, contact with chemicals, and injuries related to environmental factors increased significantly during heatwaves, especially among middle-aged and older male workers. With the predicted increase of extremely hot weather, there is a need for relevant adaptation and prevention measures at both practice and policy levels for vulnerable work groups. - Highlights: • We investigate the impacts of heatwaves on workers' health and safety. • We identify workers at higher risk of illnesses and injuries during heatwaves. • The differences between two heatwave definitions on effect estimates are compared. • Daily injury claims for outdoor industries increased by 6.2% during heatwaves. • Relevant heat prevention measures are required for vulnerable workers.« less

The Effects of Heat Adaptation on Physiology, Perception and Exercise Performance in the Heat: A Meta-Analysis.

PubMed

Tyler, Christopher J; Reeve, Tom; Hodges, Gary J; Cheung, Stephen S

2016-11-01

Exercise performance and capacity are impaired in hot, compared to temperate, conditions. Heat adaptation (HA) is one intervention commonly adopted to reduce this impairment because it may induce beneficial exercise performance and physiological and perceptual adaptations. A number of investigations have been conducted on HA but, due to large methodological differences, the effectiveness of different HA regimens remain unclear. (1) To quantify the effect of different HA regimens on exercise performance and the physiological and perceptual responses to subsequent heat exposure. (2) To offer practical HA recommendations and suggestions for future HA research based upon a systematic and quantitative synthesis of the literature. PubMed was searched for original research articles published up to, and including, 16 February 2016 using appropriate first- and second-order search terms. English-language, peer-reviewed, full-text original articles using human participants were reviewed using the four-stage process identified in the PRISMA statement. Data for the following variables were obtained from the manuscripts by at least two of the authors: participant sex, maximal oxygen consumption and age; HA duration, frequency, modality, temperature and humidity; exercise performance and capacity; core and skin temperature; heart rate, stroke volume, cardiac output, skin blood flow, sweat onset temperature, body mass loss, sweat rate, perception of thirst, volitional fluid consumption, plasma volume changes; sweat concentrations of sodium, chloride and potassium; aldosterone, arginine vasopressin, heat shock proteins (Hsp), ratings of perceived exertion (RPE) and thermal sensation. Data were divided into three groups based upon the frequency of the HA regimen. Performance and capacity data were also divided into groups based upon the type of HA used. Hedges' g effect sizes and 95 % confidence intervals were calculated. Correlations were run where appropriate. Ninety-six articles were reviewed. The most common duration was 7-14 days and the most common method of HA was the controlled work-rate approach. HA had a moderately beneficial effect on exercise capacity and performance in the heat irrespective of regimen; however, longer regimens were more effective than shorter approaches. HA had a moderate-to-large beneficial effect on lowering core body temperature before and during exercise, maintaining cardiovascular stability, and improving heat-loss pathways. Data are limited but HA may reduce oxygen consumption during subsequent exercise, improve glycogen sparing, increase the power output at lactate threshold, reduce lactate concentrations during exercise, have a trivial effect on increasing extracellular concentrations of Hsp, and improve perceived ratings of exertion and thermal sensation. HA regimens lasting <14 days induce many beneficial physiological and perceptual adaptations to high ambient temperatures, and improve subsequent exercise performance and capacity in the heat; however, the extent of the adaptations is greatest when HA regimens lasting longer than 14 days are adopted. Large methodological differences in the HA literature mean that there is still uncertainty regarding the magnitude and time course of potential adaptation for a number of physiological and perceptual variables.

Functional, interactive and critical health literacy: Varying relationships with control over care and number of GP visits.

PubMed

van der Heide, Iris; Heijmans, Monique; Schuit, A Jantine; Uiters, Ellen; Rademakers, Jany

2015-08-01

The aim of this study is to examine the extent to which functional, interactive and critical health literacy are associated with patients' perceived control over care and frequency of GP visits. Data from the Dutch 'National Panel of People with Chronic Illness or Disability' was used (N=2508). Health literacy was assessed by the Functional, Communicative and Critical Health Literacy measure. Perceived control over care was indicated by perceived ability to organize care, interact with providers and to perform self-care. By multivariate linear and logistic regression analyses, associations between health literacy and perceived control over care and subsequently frequency of GP visits were studied. Mainly interactive health literacy was associated with patients' perceived ability to organize care, interact with healthcare providers and perform self-care, whereas only functional health literacy was associated with number of GP visits. The results imply that some patients' may be less able to exert control over their care because of lower health literacy. Functional, interactive and critical health literacy vary in their relevance for patients' ability to exert control. Initiatives for strengthening patients' role in healthcare may be improved by paying attention to patients' health literacy, specifically functional and interactive health literacy. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Physiological and perceptual effects of a cooling garment during simulated industrial work in the heat.

PubMed

Butts, Cory L; Smith, Cody R; Ganio, Matthew S; McDermott, Brendon P

2017-03-01

Evaluate physiological and perceptual responses using a phase change cooling (PCC) garment during simulated work in the heat. Twenty males wearing compression undergarments, coverall suit, gloves, and hard-hat, completed two randomly assigned trials (with PCC inserts or control, CON) of simulated industrial tasks in the heat (34.2 ± 0.05 °C, 54.7 ± 0.3%RH). Trials consisted of two 20 min work bouts, a maximum performance bout, and 10 min of recovery. Physiological strain index (PSI) was lower during PCC after the second work bout and during recovery (all P < 0.05). PCC reduced heat storage (27.0 ± 7.6 W m -2 ) compared to CON (42.7 ± 9.9 W m -2 , P < 0.001). Perceptual strain index (PeSI) was reduced with PCC compared to CON (P < 0.001), however performance outcomes were not different between trials (P = 0.10). PCC during work in the heat attenuated thermal, physiological, and perceptual strain. This PCC garment could increase safety and reduce occupational heat illness risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Short Duration Heat Acclimation in Australian Football Players

PubMed Central

Kelly, Monica; Gastin, Paul B.; Dwyer, Daniel B; Sostaric, Simon; Snow, Rodney J.

2016-01-01

This study examined if five sessions of short duration (27 min), high intensity, interval training (HIIT) in the heat over a nine day period would induce heat acclimation in Australian football (AF) players. Fourteen professional AF players were matched for VO2peak (mL·kg-1·min-1) and randomly allocated into either a heat acclimation (Acc) (n = 7) or Control (Con) group (n = 7). The Acc completed five cycle ergometer HIIT sessions within a nine day period on a cycle ergometer in the heat (38.7 ± 0.5 °C; 34.4 ± 1.3 % RH), whereas Con trained in thermo-neutral conditions (22.3 ± 0.2 °C; 35.8 ± 0. % RH). Four days prior and two days post HIIT participants undertook a 30 min constant load cycling test at 60% V̇O2peak in the heat (37.9 ± 0.1 °C; 28.5 ± 0.7 % RH) during which VO2, blood lactate concentration ([Lac-]), heart rate (HR), rating of perceived exertion (RPE), thermal comfort, core and skin temperatures were measured. Heat acclimation resulted in reduced RPE, thermal comfort and [Lac-] (all p < 0.05) during the submaximal exercise test in the heat. Heart rate was lower (p = 0.007) after HIIT, in both groups. Heat acclimation did not influence any other measured variables. In conclusion, five short duration HIIT sessions in hot dry conditions induced limited heat acclimation responses in AF players during the in-season competition phase. In practice, the heat acclimation protocol can be implemented in a professional team environment; however the physiological adaptations resulting from such a protocol were limited. Key points Some minor heat acclimation adaptations can be induced in professional AF players with five 27 min non-consecutive, short duration HIIT sessions in the heat. The heat acclimation protocol employed in this study was able to be implemented in a professional team sport environment during an actual competitive season. Elevating and maintaining a high core temperature sufficient for heat acclimation likely requires a longer heat training session or some pre-heating prior to exercise. PMID:26957934

Short Duration Heat Acclimation in Australian Football Players.

PubMed

Kelly, Monica; Gastin, Paul B; Dwyer, Daniel B; Sostaric, Simon; Snow, Rodney J

2016-03-01

This study examined if five sessions of short duration (27 min), high intensity, interval training (HIIT) in the heat over a nine day period would induce heat acclimation in Australian football (AF) players. Fourteen professional AF players were matched for VO2peak (mL·kg(-1)·min(-1)) and randomly allocated into either a heat acclimation (Acc) (n = 7) or Control (Con) group (n = 7). The Acc completed five cycle ergometer HIIT sessions within a nine day period on a cycle ergometer in the heat (38.7 ± 0.5 °C; 34.4 ± 1.3 % RH), whereas Con trained in thermo-neutral conditions (22.3 ± 0.2 °C; 35.8 ± 0. % RH). Four days prior and two days post HIIT participants undertook a 30 min constant load cycling test at 60% V̇O2peak in the heat (37.9 ± 0.1 °C; 28.5 ± 0.7 % RH) during which VO2, blood lactate concentration ([Lac(-)]), heart rate (HR), rating of perceived exertion (RPE), thermal comfort, core and skin temperatures were measured. Heat acclimation resulted in reduced RPE, thermal comfort and [Lac(-)] (all p < 0.05) during the submaximal exercise test in the heat. Heart rate was lower (p = 0.007) after HIIT, in both groups. Heat acclimation did not influence any other measured variables. In conclusion, five short duration HIIT sessions in hot dry conditions induced limited heat acclimation responses in AF players during the in-season competition phase. In practice, the heat acclimation protocol can be implemented in a professional team environment; however the physiological adaptations resulting from such a protocol were limited. Key pointsSome minor heat acclimation adaptations can be induced in professional AF players with five 27 min non-consecutive, short duration HIIT sessions in the heat.The heat acclimation protocol employed in this study was able to be implemented in a professional team sport environment during an actual competitive season.Elevating and maintaining a high core temperature sufficient for heat acclimation likely requires a longer heat training session or some pre-heating prior to exercise.

Double-layer rotor magnetic shield performance analysis in high temperature superconducting synchronous generators under short circuit fault conditions

NASA Astrophysics Data System (ADS)

Hekmati, Arsalan; Aliahmadi, Mehdi

2016-12-01

High temperature superconducting, HTS, synchronous machines benefit from a rotor magnetic shield in order to protect superconducting coils against asynchronous magnetic fields. This magnetic shield, however, suffers from exerted Lorentz forces generated in light of induced eddy currents during transient conditions, e.g. stator windings short-circuit fault. In addition, to the exerted electromagnetic forces, eddy current losses and the associated effects on the cryogenic system are the other consequences of shielding HTS coils. This study aims at investigating the Rotor Magnetic Shield, RMS, performance in HTS synchronous generators under stator winding short-circuit fault conditions. The induced eddy currents in different circumferential positions of the rotor magnetic shield along with associated Joule heating losses would be studied using 2-D time-stepping Finite Element Analysis, FEA. The investigation of Lorentz forces exerted on the magnetic shield during transient conditions has also been performed in this paper. The obtained results show that double line-to-ground fault is of the most importance among different types of short-circuit faults. It was revealed that when it comes to the design of the rotor magnetic shields, in addition to the eddy current distribution and the associated ohmic losses, two phase-to-ground fault should be taken into account since the produced electromagnetic forces in the time of fault conditions are more severe during double line-to-ground fault.

Perceived exertion is as effective as the perceptual strain index in predicting physiological strain when wearing personal protective clothing.

PubMed

Borg, David N; Costello, Joseph T; Bach, Aaron J; Stewart, Ian B

2017-02-01

The perceptual strain index (PeSI) has been shown to overcome the limitations associated with the assessment of the physiological strain index (PSI), primarily the need to obtain a core body temperature measurement. The PeSI uses the subjective scales of thermal sensation and perceived exertion (RPE) to provide surrogate measures of core temperature and heart rate, respectively. Unfortunately, thermal sensation has shown large variability in providing an estimation of core body temperature. Therefore, the primary aim of this study was to determine if thermal comfort improved the ability of the PeSI to predict the PSI during exertional-heat stress. Eighteen healthy males (age: 23.5years; body mass: 79.4kg; maximal aerobic capacity: 57.2ml·kg -1 ·min -1 ) wore four different chemical/biological protective garments while walking on treadmill at a low (<325W) or moderate (326-499W) metabolic workload in environmental conditions equivalent to wet bulb globe temperatures 21, 30 or 37°C. Trials were terminated when heart rate exceeded 90% of maximum, when core body temperature reached 39°C, at 120min or due to volitional fatigue. Core body temperature, heart rate, thermal sensation, thermal comfort and RPE were recorded at 15min intervals and at termination. Multiple statistical methods were used to determine the most accurate perceptual predictor. Significant moderate relationships were observed between the PeSI (r=0.74; p<0.001), the modified PeSI (r=0.73; p<0.001) and unexpectedly RPE (r=0.71; p<0.001) with the PSI, respectively. The PeSI (mean bias: -0.8±1.5 based on a 0-10 scale; area under the curve: 0.887), modified PeSI (mean bias: -0.5±1.4 based on 0-10 scale; area under the curve: 0.886) and RPE (mean bias: -0.7±1.4 based on a 0-10 scale; area under the curve: 0.883) displayed similar predictive performance when participants experienced high-to-very high levels of physiological strain. Modifying the PeSI did not improve the subjective prediction of physiological strain. However, RPE provided an equally accurate prediction of physiological strain, particularly when high-to-very high levels of strain were observed. Therefore, given its predictive performance and user-friendliness, the evidence suggests that RPE in isolation is a practical and cost-effective tool able to estimate physiological strain during exertional-heat stress under these work conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

What Can We Learn about Workplace Heat Stress Management from a Safety Regulator Complaints Database?

PubMed Central

Hansen, Alana; Pisaniello, Dino; Varghese, Blesson; Rowett, Shelley; Hanson-Easey, Scott; Bi, Peng; Nitschke, Monika

2018-01-01

Heat exposure can be a health hazard for many Australian workers in both outdoor and indoor situations. With many heat-related incidents left unreported, it is often difficult to determine the underlying causal factors. This study aims to provide insights into perceptions of potentially unsafe or uncomfortably hot working conditions that can affect occupational health and safety using information provided by the public and workers to the safety regulator in South Australia (SafeWork SA). Details of complaints regarding heat exposure to the regulator’s “Help Centre” were assembled in a dataset and the textual data analysed thematically. The findings showed that the majority of calls relate to indoor work environments such as kitchens, factories, and warehouses. The main themes identified were work environment, health effects, and organisational issues. Impacts of hot working conditions ranged from discomfort to serious heat-related illnesses. Poor management practices and inflexibility of supervisors featured strongly amongst callers’ concerns. With temperatures predicted to increase and energy prices escalating, this timely study, using naturalistic data, highlights accounts of hot working conditions that can compromise workers’ health and safety and the need for suitable measures to prevent heat stress. These could include risk assessments to assess the likelihood of heat stress in workplaces where excessively hot conditions prevail. PMID:29509710

Body temperature regulation in diabetes

PubMed Central

Kenny, Glen P.; Sigal, Ronald J.; McGinn, Ryan

2016-01-01

ABSTRACT The effects of type 1 and type 2 diabetes on the body's physiological response to thermal stress is a relatively new topic in research. Diabetes tends to place individuals at greater risk for heat-related illness during heat waves and physical activity due to an impaired capacity to dissipate heat. Specifically, individuals with diabetes have been reported to have lower skin blood flow and sweating responses during heat exposure and this can have important consequences on cardiovascular regulation and glycemic control. Those who are particularly vulnerable include individuals with poor glycemic control and who are affected by diabetes-related complications. On the other hand, good glycemic control and maintenance of aerobic fitness can often delay the diabetes-related complications and possibly the impairments in heat loss. Despite this, it is alarming to note the lack of information regarding diabetes and heat stress given the vulnerability of this population. In contrast, few studies have examined the effects of cold exposure on individuals with diabetes with the exception of its therapeutic potential, particularly for type 2 diabetes. This review summarizes the current state of knowledge regarding the impact of diabetes on heat and cold exposure with respect to the core temperature regulation, cardiovascular adjustments and glycemic control while also considering the beneficial effects of maintaining aerobic fitness. PMID:27227101

What Can We Learn about Workplace Heat Stress Management from a Safety Regulator Complaints Database?

PubMed

Hansen, Alana; Pisaniello, Dino; Varghese, Blesson; Rowett, Shelley; Hanson-Easey, Scott; Bi, Peng; Nitschke, Monika

2018-03-06

Heat exposure can be a health hazard for many Australian workers in both outdoor and indoor situations. With many heat-related incidents left unreported, it is often difficult to determine the underlying causal factors. This study aims to provide insights into perceptions of potentially unsafe or uncomfortably hot working conditions that can affect occupational health and safety using information provided by the public and workers to the safety regulator in South Australia (SafeWork SA). Details of complaints regarding heat exposure to the regulator's "Help Centre" were assembled in a dataset and the textual data analysed thematically. The findings showed that the majority of calls relate to indoor work environments such as kitchens, factories, and warehouses. The main themes identified were work environment, health effects, and organisational issues. Impacts of hot working conditions ranged from discomfort to serious heat-related illnesses. Poor management practices and inflexibility of supervisors featured strongly amongst callers' concerns. With temperatures predicted to increase and energy prices escalating, this timely study, using naturalistic data, highlights accounts of hot working conditions that can compromise workers' health and safety and the need for suitable measures to prevent heat stress. These could include risk assessments to assess the likelihood of heat stress in workplaces where excessively hot conditions prevail.

Cortico-Striatal-Thalamic Loop Circuits of the Salience Network: A Central Pathway in Psychiatric Disease and Treatment.

PubMed

Peters, Sarah K; Dunlop, Katharine; Downar, Jonathan

2016-01-01

The salience network (SN) plays a central role in cognitive control by integrating sensory input to guide attention, attend to motivationally salient stimuli and recruit appropriate functional brain-behavior networks to modulate behavior. Mounting evidence suggests that disturbances in SN function underlie abnormalities in cognitive control and may be a common etiology underlying many psychiatric disorders. Such functional and anatomical abnormalities have been recently apparent in studies and meta-analyses of psychiatric illness using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). Of particular importance, abnormal structure and function in major cortical nodes of the SN, the dorsal anterior cingulate cortex (dACC) and anterior insula (AI), have been observed as a common neurobiological substrate across a broad spectrum of psychiatric disorders. In addition to cortical nodes of the SN, the network's associated subcortical structures, including the dorsal striatum, mediodorsal thalamus and dopaminergic brainstem nuclei, comprise a discrete regulatory loop circuit. The SN's cortico-striato-thalamo-cortical loop increasingly appears to be central to mechanisms of cognitive control, as well as to a broad spectrum of psychiatric illnesses and their available treatments. Functional imbalances within the SN loop appear to impair cognitive control, and specifically may impair self-regulation of cognition, behavior and emotion, thereby leading to symptoms of psychiatric illness. Furthermore, treating such psychiatric illnesses using invasive or non-invasive brain stimulation techniques appears to modulate SN cortical-subcortical loop integrity, and these effects may be central to the therapeutic mechanisms of brain stimulation treatments in many psychiatric illnesses. Here, we review clinical and experimental evidence for abnormalities in SN cortico-striatal-thalamic loop circuits in major depression, substance use disorders (SUD), anxiety disorders, schizophrenia and eating disorders (ED). We also review emergent therapeutic evidence that novel invasive and non-invasive brain stimulation treatments may exert therapeutic effects by normalizing abnormalities in the SN loop, thereby restoring the capacity for cognitive control. Finally, we consider a series of promising directions for future investigations on the role of SN cortico-striatal-thalamic loop circuits in the pathophysiology and treatment of psychiatric disorders.

Cortico-Striatal-Thalamic Loop Circuits of the Salience Network: A Central Pathway in Psychiatric Disease and Treatment

PubMed Central

Peters, Sarah K.; Dunlop, Katharine; Downar, Jonathan

2016-01-01

The salience network (SN) plays a central role in cognitive control by integrating sensory input to guide attention, attend to motivationally salient stimuli and recruit appropriate functional brain-behavior networks to modulate behavior. Mounting evidence suggests that disturbances in SN function underlie abnormalities in cognitive control and may be a common etiology underlying many psychiatric disorders. Such functional and anatomical abnormalities have been recently apparent in studies and meta-analyses of psychiatric illness using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). Of particular importance, abnormal structure and function in major cortical nodes of the SN, the dorsal anterior cingulate cortex (dACC) and anterior insula (AI), have been observed as a common neurobiological substrate across a broad spectrum of psychiatric disorders. In addition to cortical nodes of the SN, the network’s associated subcortical structures, including the dorsal striatum, mediodorsal thalamus and dopaminergic brainstem nuclei, comprise a discrete regulatory loop circuit. The SN’s cortico-striato-thalamo-cortical loop increasingly appears to be central to mechanisms of cognitive control, as well as to a broad spectrum of psychiatric illnesses and their available treatments. Functional imbalances within the SN loop appear to impair cognitive control, and specifically may impair self-regulation of cognition, behavior and emotion, thereby leading to symptoms of psychiatric illness. Furthermore, treating such psychiatric illnesses using invasive or non-invasive brain stimulation techniques appears to modulate SN cortical-subcortical loop integrity, and these effects may be central to the therapeutic mechanisms of brain stimulation treatments in many psychiatric illnesses. Here, we review clinical and experimental evidence for abnormalities in SN cortico-striatal-thalamic loop circuits in major depression, substance use disorders (SUD), anxiety disorders, schizophrenia and eating disorders (ED). We also review emergent therapeutic evidence that novel invasive and non-invasive brain stimulation treatments may exert therapeutic effects by normalizing abnormalities in the SN loop, thereby restoring the capacity for cognitive control. Finally, we consider a series of promising directions for future investigations on the role of SN cortico-striatal-thalamic loop circuits in the pathophysiology and treatment of psychiatric disorders. PMID:28082874

Patients' and neurologists' perception of epilepsy and psychogenic nonepileptic seizures.

PubMed

Whitehead, Kimberley; Kandler, Rosalind; Reuber, Markus

2013-04-01

Although differences in illness perceptions between neurologists and patients with epilepsy or psychogenic nonepileptic seizures (PNES) are likely to be clinically relevant, this is the first study to attempt a direct comparison. In addition, this study compares the illness perceptions of patients with epilepsy with those of patients with PNES. Thirty-four patients with epilepsy, 40 patients with PNES, and 45 neurologists were recruited. All patient participants completed versions of the illness perception questionnaire revised (IPQ-R) adapted for epileptic or nonepileptic seizure disorders, single-item symptom attribution question (SAQ), Hospital Anxiety and Depression Scale (HADS), Quality of Life in Epilepsy-31 (QOLIE-31), and Liverpool Seizure Severity Scale (LSSS). Participating neurologists completed two versions of the IPQ-R and two SAQs for epileptic and nonepileptic seizure disorders. Differences in illness perceptions between patients with epilepsy and patients with PNES were minor compared to those between patients with either seizure disorder and neurologists. Neurologists considered both seizure disorders more treatable and more amenable to personal control than did the patients themselves. Neurologists had much more polarized views of the etiology of both conditions; whereas patients mostly considered the causes of their seizure disorders as partially "physical" and partially "psychological," neurologists perceived epilepsy as an essentially "physical" and PNES as a clearly "psychological" problem. There are considerable differences between the illness perceptions of patients with seizure disorders and their doctors, which could represent barriers to successful clinical management. In particular, a discrepancy between neurologists' and patients' beliefs about the personal control that patients may be able to exert over PNES could contribute to the confusion or anger some patients report after the diagnosis has been explained to them. Furthermore, patients' endorsement of "physical" causes for PNES may reflect an unrealistic faith in the effectiveness of "physical" treatments and could be a cause of tension in patients' relationship with their doctor, for instance when the neurologist attempts to withdraw antiepileptic drug treatment or refers patients for psychological interventions. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

Identification of Indirect Effects in a Cognitive Patient Education (COPE) Intervention for Low Back Pain.

PubMed

Mansell, Gemma; Storheim, Kjersti; Løchting, Ida; Werner, Erik L; Grotle, Margreth

2017-12-01

Many interventions for the treatment of low back pain exist, but the mechanisms through which such treatments work are not always clear. This situation is especially true for biopsychosocial interventions that incorporate several different components and methods of delivery. The study objective was to examine the indirect effects of the Cognitive Patient Education (COPE) intervention via illness perceptions, back pain myths, and pain catastrophizing on disability outcome. This study was a secondary analysis of the COPE randomized controlled trial. Mediation analysis techniques were employed to examine the indirect effects of the COPE intervention via residualized change (baseline - posttreatment) in the 3 variables hypothesized to be targeted by the COPE intervention on posttreatment disability outcome. Pain intensity at baseline, pain duration, clinician type, and a treatment-mediator interaction term were controlled for in the analysis. Preliminary analyses confirmed that changes in pain catastrophizing and illness perceptions (not back pain myths) were related to both allocation to the intervention arm and posttreatment disability score. The treatment exerted statistically significant indirect effects via changes in illness perceptions and pain catastrophizing on posttreatment disability score (illness perceptions standardized indirect effect = 0.09 [95% CI = 0.03 to 0.16]; pain catastrophizing standardized indirect effect = 0.05 [95% CI = 0.01 to 0.12]). However, the inclusion of an interaction term led to the indirect effects being significantly reduced, with the effects no longer being statistically significant. This study presents a secondary analysis of variables not identified a priori as being potentially important treatment targets; other, unmeasured factors could also be important in explaining treatment effects. The finding that small indirect effects of the COPE intervention via changes in illness perceptions and pain catastrophizing on posttreatment disability could be estimated indicates that these variables may be viable treatment targets for biopsychosocial interventions; however, this finding must be viewed in light of the adjusted analyses, which showed that the indirect effects were significantly reduced through the inclusion of a treatment-mediator interaction term. © Crown copyright 2015

Thermal, physiological and perceptual strain mediate alterations in match-play tennis under heat stress

PubMed Central

Périard, Julien D; Racinais, Sébastien; Knez, Wade L; Herrera, Christopher P; Christian, Ryan J; Girard, Olivier

2014-01-01

Objectives This study compared the thermal, physiological and perceptual responses associated with match-play tennis in HOT (∼34°C wet-bulb-globe temperature (WBGT)) and COOL (∼19°C WBGT) conditions, along with the accompanying alterations in match characteristics. Methods 12 male tennis players undertook two matches for an effective playing time (ie, ball in play) of 20 min, corresponding to ∼119 and ∼102 min of play in HOT and COOL conditions, respectively. Rectal and skin temperatures, heart rate, subjective ratings of thermal comfort, thermal sensation and perceived exertion were recorded, along with match characteristics. Results End-match rectal temperature increased to a greater extent in the HOT (∼39.4°C) compared with the COOL (∼38.7°C) condition (p<0.05). Thigh skin temperature was higher throughout the HOT match (p<0.001). Heart rate, thermal comfort, thermal sensation and perceived exertion were also higher during the HOT match (p<0.001). Total playing time was longer in the HOT compared with the COOL match (p<0.05). Point duration (∼7.1 s) was similar between conditions, while the time between points was ∼10 s longer in the HOT relative to the COOL match (p<0.05). This led to a ∼3.4% lower effective playing percentage in the heat (p<0.05). Although several thermal, physiological and perceptual variables were individually correlated to the adjustments in time between points and effective playing percentage, thermal sensation was the only predictor variable associated with both adjustments (p<0.005). Conclusions These adjustments in match-play tennis characteristics under severe heat stress appear to represent a behavioural strategy adopted to minimise or offset the sensation of environmental conditions being rated as difficult. PMID:24668377

An Exertional Heat Stroke Survivor's Return to Running: An Integrated Approach on the Treatment, Recovery, and Return to Activity.

PubMed

Adams, William M; Hosokawa, Yuri; Huggins, Robert A; Mazerolle, Stephanie M; Casa, Douglas J

2016-08-01

Evidence-based best practices for the recognition and treatment of exertional heat stroke (EHS) indicate that rectal thermometry and immediate, aggressive cooling via cold-water immersion ensure survival from this medical condition. However, little is known about the recovery, medical follow-up, and return to activity after an athlete has suffered EHS. To highlight the transfer of evidenced-based research into clinical practice by chronicling the treatment, recovery, and return to activity of a runner who suffered an EHS during a warm-weather road race. Case study. Warm-weather road race. 53-y-old recreationally active man. A runner's treatment, recovery, and return to activity from EHS and 2014 Falmouth Road Race performance. Runner's perceptions and experiences with EHS, body temperature, heart rate, hydration status, exercise intensity. The runner successfully completed the 2014 Falmouth Road Race without incident of EHS. Four dominant themes emerged from the data: predisposing factors, ideal treatment, lack of medical follow-up, and patient education. The first theme identified 3 predisposing factors that contributed to the runner's EHS: hydration, sleep loss, and lack of heat acclimatization. The runner received ideal treatment using evidence-based best practices. A lack of long-term medical care following the EHS with no guidance on the runner's return to full activity was observed. The runner knew very little about EHS before the 2013 race, which drove him to seek knowledge as to why he suffered EHS. Using this newly learned information, he successfully completed the 2014 Falmouth Road Race without incident. This case supports prior literature examining the factors that predispose individuals to EHS. Although evidence-based best practices regarding prompt recognition and treatment of EHS ensure survival, this case highlights the lack of medical follow-up and physician-guided return to activity after EHS.

Biological control of surface temperature in the Arabian Sea

NASA Technical Reports Server (NTRS)

Sathyendranath, Shubha; Gouveia, Albert D.; Shetye, Satish R.; Ravindran, P.; Platt, Trevor

1991-01-01

In the Arabian Sea, the southwest monsoon promotes seasonal upwelling of deep water, which supplies nutrients to the surface layer and leads to a marked increase in phytoplankton growth. Remotely sensed data on ocean color are used here to show that the resulting distribution of phytoplankton exerts a controlling influence on the seasonal evolution of sea surface temperature. This results in a corresponding modification of ocean-atmosphere heat exchange on regional and seasonal scales. It is shown that this biological mechanism may provide an important regulating influence on ocean-atmosphere interactions.

Living with illness and self-transcendence: the lived experience of patients with spinal muscular atrophy.

PubMed

Ho, Hsin-Mei; Tseng, Ying-Hua; Hsin, Yu-Mei; Chou, Fan-Hao; Lin, Wei-Ting

2016-11-01

The aim of this study was to explore the lived experiences of patients afflicted with spinal muscular atrophy. Existing research studies on spinal muscular atrophy address the physical and psychological effects and complications of the disease; they also provide suggestions for how to improve the current management of this disease. However, information is limited on the disease process and the lived experience of spinal muscular atrophy patients. A phenomenological approach was conducted. Through 18 in-depth interviews recorded by a pen voice recorder, this study collected data obtained from a purposive sample of nine patients from the, 'Taiwan spinal muscular atrophy Families,' between November 2010-August 2011. The audio recordings were transcribed verbatim and data were analysed using Colaizzi's steps. Four themes and eight subthemes were identified: a loss of control (loss of muscular strength and independence), breaking limitations (assistive device use and mobility design), transcending limitations (independence/autonomy and social development) and living with hope (cherishing life and self-control). The results showed that the lived experiences of the spinal muscular atrophy patients involved living with illness, transcending the self and pursuing the meaning of life. Facing a life-threatening illness, these patients made self-adjustments in their lifestyles and exerted themselves to positively cope with hardships and maintain dignity and self-control. These findings could serve as evidence-based practice resources for healthcare professionals in helping individuals and their family members gain an in-depth understanding of spinal muscular atrophy's progression and life course and assist individuals in improving self-integrity to with hope. © 2016 John Wiley & Sons Ltd.

Evaluation of agreements between managed care organizations and providers of community-based mental illness and addiction disorder treatments.

PubMed

Rosenbaum, Sara; Mauery, D Richard; Teitelbaum, Joel; Vandivort-Warren, Rita

2002-02-01

To analyze the scope, content, and nature of contracts between managed care organizations (MCOs) and community-based mental illness and addiction disorder treatment and prevention service providers, focusing on implications for managed care policy. Qualitative and quantitative document content analysis. We reviewed and coded 107 provider contracts from 17 states. Data were aggregated on MCO and provider demographics, scope of services, contractual obligations, and financial reimbursement mechanisms. Results were compared with those from a similar study conducted in 1996 with a sample of 50 contracts to identify changes over time. The MCOs purchased relatively few services from providers, omitting many services integral to the proper management of mental illness and addiction disorders. Service duties were often ambiguously described, leading to potentially significant and unanticipated financial risk for providers. The MCOs exert strong control over treatment decision making. Capitation and other risk-based payment arrangements are increasingly common, although most continue to use fee-for-service reimbursement methods. Contracts are structured to remove provider bargaining power; they allow MCOs to unilaterally amend all provisions on notice and without negotiation and permit termination "at will." Managed care contracts favor the needs of the managed care industry and are constructed to (1) shift significant amounts of financial risk onto providers and (2) manage and restrain providers' choices over the use of benefits through close oversight, financial controls, and incentives. Because a signed contract is a precondition to access to patients and insurance revenues, health professionals must sign them and indicate a general inability to negotiate their terms.

Effects of caffeine and menthol on cognition and mood during simulated firefighting in the heat.

PubMed

Zhang, Yang; Balilionis, Gytis; Casaru, Catalina; Geary, Colleen; Schumacker, Randall E; Neggers, Yasmin H; Curtner-Smith, Matthew D; Richardson, Mark T; Bishop, Phillip A; Green, James M

2014-05-01

This study examined the separate effects of caffeine and menthol on cognition and mood during simulated firefighting in the heat. Participants (N = 10) performed three trials in a counterbalanced order, either with 400 mg caffeine, menthol lozenges, or placebo. The simulated firefighting consisted of 2 bouts of 20-min treadmill exercise and one bout of 20-min stepping exercise in the heat with two brief 15-min rest periods between each exercise phase. Exercise induced significant dehydration (>3%) and elevated rectal temperature (>38.9 °C), for all three conditions. Neither caffeine nor menthol reduced perceived exertion compared to placebo (p > 0.05). Mood ratings (i.e., alertness, hedonic tone, tension) significantly deteriorated over time (p < 0.05), but there was no difference among the three conditions. Simple reaction time, short-term memory, and retrieval memory did not alter with treatments or repeated evaluations. Reaction accuracy from a math test remained unchanged throughout the experimental period; reaction time from the math test was significantly faster after exposure to the heat (p < 0.05). It is concluded that, exhaustive exercise in the heat severely impacted mood, but minimally impacted cognition. These treatments failed to show ergogenic benefits in a simulated firefighting paradigm in a hot environment. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Effect of mesoscale oceanic eddies on mid-latitude storm-tracks.

NASA Astrophysics Data System (ADS)

Foussard, Alexis; Lapeyre, Guillaume; Plougonven, Riwal

2017-04-01

Sharp sea surface temperature (SST) gradients associated with oceanic western boundary currents (WBC) exert an influence on the position and intensity of mid-latitude storm-tracks. This occurs through strong surface baroclinicity maintained by cross frontal SST gradient and deep vertical atmospheric motion due to convection on the warm flank of the WBC. However the additional role of mesoscale oceanic structures (30-300km) has not yet been explored although they have a non-negligible influence on surface heat fluxes. Using the Weather Research and Forecasting model, we investigate the potential role of these oceanic eddies in the case of an idealized atmospheric mid-latitude storm track forced by a mesoscale oceanic eddy field superposed with a large-scale SST gradient. Surface latent and sensible fluxes are shown to react with a non-linear response to the SST variations, providing additional heat and moisture supply at large scales. The atmospheric response is not restricted to the boundary layer but reaches the free troposphere, especially through increased water vapor vertical transport and latent heat release. This additional heating in presence of eddies is balanced by a shift of the storm-track and its poleward heat flux toward high latitudes, with amplitude depending on atmospheric configuration and eddies amplitude. We also explore how this displacement of perturbations changes the position and structure of the mid-latitude jet through eddy momentum fluxes.

Influence of food acidulants and antioxidant spices on the bioaccessibility of beta-carotene from selected vegetables.

PubMed

Veda, Supriya; Platel, Kalpana; Srinivasan, Krishnapura

2008-09-24

Four common food acidulants--amchur, lime, tamarind, and kokum--and two antioxidant spices--turmeric and onion--were examined for their influence on the bioaccessibility of beta-carotene from two fleshy and two leafy vegetables. Amchur and lime generally enhanced the bioaccessibility of beta-carotene from these test vegetables in many instances. Such an improved bioaccessibility was evident in both raw and heat-processed vegetables. The effect of lime juice was generally more pronounced than that of amchur. Turmeric significantly enhanced the bioaccessibility of beta-carotene from all of the vegetables tested, especially when heat-processed. Onion enhanced the bioaccessibility of beta-carotene from pressure-cooked carrot and amaranth leaf and from open-pan-boiled pumpkin and fenugreek leaf. Lime juice and the antioxidant spices turmeric and onion minimized the loss of beta-carotene during heat processing of the vegetables. In the case of antioxidant spices, improved bioaccessibility of beta-carotene from heat-processed vegetables is attributable to their role in minimizing the loss of this provitamin. Lime juice, which enhanced the bioaccessibility of this provitamin from both raw and heat-processed vegetables, probably exerted this effect by some other mechanism in addition to minimizing the loss of beta-carotene. Thus, the presence of food acidulants (lime juice/amchur) and antioxidant spices (turmeric/onion) proved to be advantageous in the context of deriving maximum beta-carotene from the vegetable sources.

Case report: severe heat stroke with multiple organ dysfunction – a novel intravascular treatment approach

PubMed Central

Broessner, Gregor; Beer, Ronny; Franz, Gerhard; Lackner, Peter; Engelhardt, Klaus; Brenneis, Christian; Pfausler, Bettina; Schmutzhard, Erich

2005-01-01

Introduction We report the case of a patient who developed a severe post-exertional heat stroke with consecutive multiple organ dysfunction resistant to conventional antipyretic treatment, necessitating the use of a novel endovascular device to combat hyperthermia and maintain normothermia. Methods A 38-year-old male suffering from severe heat stroke with predominant signs and symptoms of encephalopathy requiring acute admission to an intensive care unit, was admitted to a ten-bed neurological intensive care unit of a tertiary care hospital. The patient developed consecutive multiple organ dysfunction with rhabdomyolysis, and hepatic and respiratory failure. Temperature elevation was resistant to conventional treatment measures. Aggressive intensive care treatment included forced diuresis and endovascular cooling to combat hyperthermia and maintain normothermia. Results Analyses of serum revealed elevation of proinflammatory cytokines (TNF alpha, IL-6), cytokines (IL-2R), anti-inflammatory cytokines (IL-4) and chemokines (IL-8) as well as signs of rhabdomyolysis and hepatic failure. Aggressive intensive care treatment as forced diuresis and endovascular cooling (CoolGard® and CoolLine®) to combat hyperthermia and maintain normothermia were used successfully to treat this severe heat stroke. Conclusion In this case of severe heat stroke, presenting with multiple organ dysfunction and elevation of cytokines and chemokines, which was resistant to conventional cooling therapies, endovascular cooling may have contributed significantly to the reduction of body temperature and, possibly, avoided a fatal result. PMID:16285034

Dysfunction of Iron Metabolism and Iron-Regulatory Proteins in the Rat Hippocampus After Heat Stroke.

PubMed

Liu, Jing; Wan, Shengming; Zhang, Yun; Zhang, Shu; Zhang, Hongying; Wu, Shiwen

2018-05-11

Heat stroke, the most serious type of heat illness, refers to the presence of hyperthermia (core temperature >40°C), accompanied by central nervous system dysfunction. The hippocampus is a particularly vulnerable region in the early stage of heat stroke. Increasing evidence suggests that dysregulation of brain iron metabolism is involved in many neurodegenerative diseases. However, whether heat stroke causes dysfunction of iron metabolism, as well as iron-regulatory proteins, in the hippocampus remains unknown. The present study was conducted to explore the effects on spatial learning and memory, as well as iron content, ferroportin 1 (Fpn1), and hepcidin expression in the hippocampus after heat stroke in rats. Compared with the Sham group, learning ability and memory declined in rats after heat stroke. Iron concentration was significantly increased in the hippocampus. Expression of Fpn1 protein significantly decreased in the hippocampus, while expression of hepcidin increased. Interestingly, Fpn1 mRNA expression in the hippocampus increased. Our data thereby indicate that heat stroke can decrease learning ability and memory in rats. The mechanism may be related to changes of iron levels, as well as Fpn1 and hepcidin expression, in the hippocampus. Furthermore, hepcidin may rapidly decrease cellular Fpn1 protein levels, even under conditions of iron loading, indicating that hepcidin is a more dominant regulator of Fpn1 than is iron.

Vulnerability to extreme heat and climate change: is ethnicity a factor?

PubMed Central

Hansen, Alana; Bi, Linda; Saniotis, Arthur; Nitschke, Monika

2013-01-01

Background With a warming climate, it is important to identify sub-populations at risk of harm during extreme heat. Several international studies have reported that individuals from ethnic minorities are at increased risk of heat-related illness, for reasons that are not often discussed. Objective The aim of this article is to investigate the underpinning reasons as to why ethnicity may be associated with susceptibility to extreme heat, and how this may be relevant to Australia’s population. Design Drawing upon literary sources, the authors provide commentary on this important, yet poorly understood area of heat research. Results Social and economic disparities, living conditions, language barriers, and occupational exposure are among the many factors contributing to heat-susceptibility among minority ethnic groups in the United States. However, there is a knowledge gap about socio-cultural influences on vulnerability in other countries. Conclusion More research needs to be undertaken to determine the effects of heat on tourists, migrants, and refugees who are confronted with a different climatic environment. Thorough epidemiological investigations of the association between ethnicity and heat-related health outcomes are required, and this could be assisted with better reporting of nationality data in health statistics. Climate change adaptation strategies in Australia and elsewhere need to be ethnically inclusive and cognisant of an upward trend in the proportion of the population who are migrants and refugees. PMID:23899408

Comparison of heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion.

PubMed

Zhao, Yijie; Yi, Wen; Chan, Albert P C; Chan, Daniel W M

2017-10-01

A hot environment combined with physically demanding tasks can subject workers to a higher risk of heat stress. A series of regulations and guidelines have been proposed to design appropriate anti-heat stress work uniform to reduce body heat strain. The present study aimed to examine heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion in the heat. 10 healthy males performed intermittent treadmill running/walking to exhaustion, followed by 30min passive recovery sitting in a climatic chamber, which simulated the hot and humid outdoor environment (34°C temperature, 60% relative humidity, 0.3m/s air velocity, and 450W/m 2 solar radiation). The participants took part in five wear trials in counter-balanced order, including Sportswear, CIC Uniform, NEW Uniform, ICEBANK Cooling Vest, and NEW Cooling Vest, which have different levels of cooling capacity. Core temperature, skin temperature, heart rate, sweat loss, ratings of perceived exertion, and thermal sensations were measured throughout the entire heat exposure period. Physiological heat strain indices, including the physiological strain index (PhSI) and the perceptual strain index (PeSI), were used as a yardstick to quantify and compare the rate of recovery. Significantly lower physiological strain was observed in the newly developed NEW Uniform and NEW Cooling Vest groups compared with the commonly worn CIC Uniform group during recovery. At the end of the recovery period, participants in NEW Cooling Vest achieved the highest recovery (42.18% in PhSI and 81.08% in PeSI), followed by ICEBANK Cooling Vest, Sportswear, NEW Uniform, and CIC Uniform. The cooling capacity of anti-heat stress clothing ensembles and the recovery time significantly affect the rate of recovery in PhSI and PeSI, which may benefit the industry by formulating the appropriate work-rest schedule by considering the clothing effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

Work Rate during Self-paced Exercise is not Mediated by the Rate of Heat Storage.

PubMed

Friesen, Brian J; Périard, Julien D; Poirier, Martin P; Lauzon, Martin; Blondin, Denis P; Haman, Francois; Kenny, Glen P

2018-01-01

To date, there have been mixed findings on whether greater anticipatory reductions in self-paced exercise intensity in the heat are mediated by early differences in rate of body heat storage. The disparity may be due to an inability to accurately measure minute-to-minute changes in whole-body heat loss. Thus, we evaluated whether early differences in rate of heat storage can mediate exercise intensity during self-paced cycling at a fixed rate of perceived exertion (RPE of 16; hard-to-very-hard work effort) in COOL (15°C), NORMAL (25°C), and HOT (35°C) ambient conditions. On separate days, nine endurance-trained cyclists exercised in COOL, NORMAL, and HOT conditions at a fixed RPE until work rate (measured after first 5 min of exercise) decreased to 70% of starting values. Whole-body heat loss and metabolic heat production were measured by direct and indirect calorimetry, respectively. Total exercise time was shorter in HOT (57 ± 20 min) relative to both NORMAL (72 ± 23 min, P = 0.004) and COOL (70 ± 26 min, P = 0.045). Starting work rate was lower in HOT (153 ± 31 W) compared with NORMAL (166 ± 27 W, P = 0.024) and COOL (170 ± 33 W, P = 0.037). Rate of heat storage was similar between conditions during the first 4 min of exercise (all P > 0.05). Thereafter, rate of heat storage was lower in HOT relative to NORMAL and COOL until 30 min of exercise (last common time-point between conditions; all P < 0.05). Further, rate of heat storage was significantly higher in COOL compared with NORMAL at 15 min (P = 0.026) and 20 min (P = 0.020) of exercise. No differences were measured at end exercise. We show that rate of heat storage does not mediate exercise intensity during self-paced exercise at a fixed RPE in cool to hot ambient conditions.

Heat Acclimation by Post-Exercise Hot Water Immersion in the Morning Reduces Thermal Strain During Morning and Afternoon Exercise-Heat-Stress.

PubMed

Zurawlew, Michael J; Mee, Jessica A; Walsh, Neil P

2018-05-10

Recommendations state that to acquire the greatest benefit from heat acclimation the clock-time of heat acclimation sessions should match the clock-time of expected exercise-heat stress. It remains unknown if adaptations by post-exercise hot water immersion (HWI) demonstrate time of day dependent adaptations. Thus, we examined whether adaptations following post-exercise HWI completed in the morning were present during morning and afternoon exercise-heat stress. Ten males completed an exercise-heat stress test commencing in the morning (0945-h: AM) and afternoon (1445-h: PM; 40 min; 65% V̇O 2max treadmill run) before (PRE) and after (POST) heat acclimation. The 6-day heat acclimation intervention involved a daily, 40 min treadmill-run (65% V̇O 2max ) in temperate conditions followed by ≤ 40 min HWI (40°C; 0630-1100-h). Adaptations by 6-day post-exercise HWI in the morning were similar in the morning and afternoon. Reductions in resting rectal temperature (T re ; AM; -0.34 ± 0.24°C, PM; -0.27 ± 0.23°C; P = 0.002), T re at sweating onset (AM; -0.34 ± 0.24°C, PM; -0.31 ± 0.25°C; P = 0.001), and end-exercise T re (AM; -0.47 ± 0.33°C, PM; -0.43 ± 0.29°C; P = 0.001), heart rate (AM; -14 ± 7 beats∙min -1 , PM; -13 ± 6 beats∙min -1 ; P < 0.01), rating of perceived exertion (P = 0.01), and thermal sensation (P = 0.005) were not different in the morning compared to the afternoon. Morning heat acclimation by post-exercise hot water immersion induced adaptions at rest and during exercise-heat stress in the morning and mid-afternoon.

Nanoparticle-based hyperthermia distinctly impacts production of ROS, expression of Ki-67, TOP2A, and TPX2, and induction of apoptosis in pancreatic cancer.

PubMed

Ludwig, Robert; Teran, Francisco J; Teichgraeber, Ulf; Hilger, Ingrid

2017-01-01

So far, the therapeutic outcome of hyperthermia has shown heterogeneous responses depending on how thermal stress is applied. We studied whether extrinsic heating (EH, hot air) and intrinsic heating (magnetic heating [MH] mediated by nanoparticles) induce distinct effects on pancreatic cancer cells (PANC-1 and BxPC-3 cells). The impact of MH (100 µg magnetic nanoparticles [MNP]/mL; H=23.9 kA/m; f=410 kHz) was always superior to that of EH. The thermal effects were confirmed by the following observations: 1) decreased number of vital cells, 2) altered expression of pro-caspases, and 3) production of reactive oxygen species, and 4) altered mRNA expression of Ki-67, TOP2A, and TPX2. The MH treatment of tumor xenografts significantly ( P ≤0.05) reduced tumor volumes. This means that different therapeutic outcomes of hyperthermia are related to the different responses cells exert to thermal stress. In particular, intratumoral MH is a valuable tool for the treatment of pancreatic cancers.

Nanoparticle-based hyperthermia distinctly impacts production of ROS, expression of Ki-67, TOP2A, and TPX2, and induction of apoptosis in pancreatic cancer

PubMed Central

Ludwig, Robert; Teran, Francisco J; Teichgraeber, Ulf; Hilger, Ingrid

2017-01-01

So far, the therapeutic outcome of hyperthermia has shown heterogeneous responses depending on how thermal stress is applied. We studied whether extrinsic heating (EH, hot air) and intrinsic heating (magnetic heating [MH] mediated by nanoparticles) induce distinct effects on pancreatic cancer cells (PANC-1 and BxPC-3 cells). The impact of MH (100 µg magnetic nanoparticles [MNP]/mL; H=23.9 kA/m; f=410 kHz) was always superior to that of EH. The thermal effects were confirmed by the following observations: 1) decreased number of vital cells, 2) altered expression of pro-caspases, and 3) production of reactive oxygen species, and 4) altered mRNA expression of Ki-67, TOP2A, and TPX2. The MH treatment of tumor xenografts significantly (P≤0.05) reduced tumor volumes. This means that different therapeutic outcomes of hyperthermia are related to the different responses cells exert to thermal stress. In particular, intratumoral MH is a valuable tool for the treatment of pancreatic cancers. PMID:28223795

Palm kernel cake extract exerts hepatoprotective activity in heat-induced oxidative stress in chicken hepatocytes.

PubMed

Oskoueian, Ehsan; Abdullah, Norhani; Idrus, Zulkifli; Ebrahimi, Mahdi; Goh, Yong Meng; Shakeri, Majid; Oskoueian, Armin

2014-10-02

Palm kernel cake (PKC), the most abundant by-product of oil palm industry is believed to contain bioactive compounds with hepatoprotective potential. These compounds may serve as hepatoprotective agents which could help the poultry industry to alleviate adverse effects of heat stress on liver function in chickens. This study was performed to evaluate the hepatoprotective potential of PKC extract in heat-induced oxidative stress in chicken hepatocytes. The nature of the active metabolites and elucidation of the possible mechanism involved were also investigated. The PKC extract possessed free radical scavenging activity with values significantly (p < 0.05) lower than silymarin as the reference antioxidant. Heat-induced oxidative stress in chicken hepatocyte impaired the total protein, lipid peroxidation and antioxidant enzymes activity significantly (p < 0.05). Treatment of heat-induced hepatocytes with PKC extract (125 μg/ml) and silymarin as positive control increased these values significantly (p < 0.05). The real time PCR and western blot analyses revealed the significant (p < 0.05) up-regulation of oxidative stress biomarkers including TNF-like, IFN-γ and IL-1β genes; NF-κB, COX-2, iNOS and Hsp70 proteins expression upon heat stress in chicken hepatocytes. The PKC extract and silymarin were able to alleviate the expression of all of these biomarkers in heat-induced chicken hepatocytes. The gas chromatography-mass spectrometry analysis of PKC extract showed the presence of fatty acids, phenolic compounds, sugar derivatives and other organic compounds such as furfural which could be responsible for the observed hepatoprotective activity. Palm kernel cake extract could be a potential agent to protect hepatocytes function under heat induced oxidative stress.

Effects of reference analgesics and psychoactive drugs on the noxious heat threshold of mice measured by an increasing-temperature water bath.

PubMed

Boros, Melinda; Benkó, Rita; Bölcskei, Kata; Szolcsányi, János; Barthó, Loránd; Pethő, Gábor

2013-12-01

The study aimed at validating an increasing-temperature water bath suitable for determining the noxious heat threshold for use in mice. The noxious heat threshold was determined by immersing the tail of the gently held awake mouse into a water container whose temperature was near-linearly increased at a rate of 24°C/min. until the animal withdrew its tail, that is, heating attained the noxious threshold. The effects of standard analgesic, neuroleptic and anxiolytic drugs were investigated in a parallel way on both the noxious heat threshold and the psychomotor activity assessed by the open field test. Morphine, diclofenac and metamizol (dipyrone) elevated the heat threshold of mice with minimum effective doses of 6, 30 and 1000 mg/kg i.p., respectively. These doses of morphine and diclofenac failed to induce any remarkable effect on psychomotor activity in the open field test while that of metamizol exerted a profound inhibition. The anxiolytic diazepam and the neuroleptic droperidol at doses evoking a mild and moderate, respectively, psychomotor inhibition failed to alter the heat threshold. Combination of a subliminal dose of morphine (regarding both antinociceptive and psychomotor inhibitory action) with diclofenac, metamizol, diazepam or droperidol at doses also subliminal regarding the thermal antinociceptive effect elevated the noxious heat threshold without major additional effects in the open field test. It is concluded that the increasing-temperature water bath is suitable for studying the thermal antinociceptive effects of morphine and diclofenac as well as the morphine-sparing action of diclofenac, metamizol, droperidol and diazepam. Behavioural testing is recommended when testing analgesics. © 2013 Nordic Pharmacological Society. Published by John Wiley & Sons Ltd.

Perceptions of psychosis, coping, appraisals, and psychological distress in the relatives of patients with schizophrenia: an exploration using self-regulation theory.

PubMed

Fortune, Dónal G; Smith, Jo V; Garvey, Kay

2005-09-01

Following Leventhal's self-regulation model, the purpose of the present study was to provide an examination of the relationship between psychosis perceptions, coping strategies, appraisals, and distress in the relatives of patients with schizophrenia. Cross-sectional study. Participants were 42 relatives of patients with schizophrenia who completed the Hospital Anxiety and Depression Scale (HADS), a brief coping strategies measure (COPE), the Revised Illness Perception Questionnaire (IPQR), and a measure of primary and secondary appraisals (Family Questionnaire). In general, carers who viewed their relative's psychosis as chronic, who had a stronger illness identity (experience of symptoms), who held a stronger belief in the severity of its consequences, and who reported weaker beliefs in treatment control but stronger beliefs that their relative could exert control over their condition had higher distress scores. Coping through seeking emotional support, the use of religion/spirituality, active coping, acceptance, and positive reframing were associated with less distress, while coping through self-blame was associated with higher distress scores. Hierarchical regression demonstrated that illness perceptions and coping (acceptance, positive reframing, and self-blame), respectively, made significant additional contributions to the variance in distress when entered after demographics, and primary and secondary appraisals. Furthermore, a mediational analysis suggested that coping strategies characterized by greater positive reframing, less self-blame, and greater acceptance mediated the relationship between distress, and both illness identity and carer's beliefs about how much personal control the patient could exercise over their condition. There was no mediational effect of coping on the relationship between distress and carers' perceptions about symptom control through medical treatment. Results provide partial but not unequivocal support for the self-regulation model in the current sample. Findings may invite us to consider the further use of the self-regulation/common sense model as a framework for understanding distress in the carers of people with a diagnosis of schizophrenia.

[Social exclusion and discrimination of chronically mentally ill people in the Lodz region].

PubMed

Rasmus, Paweł; Nowaczyńska, Ewa; Stetkiewicz-Lewandowicz, Agnieszka; Rasmus, Alicja; Sobów, Tomasz

2013-11-01

Mental crisis exerts a negative effect on somatic, psychological and social functioning of a mentally ill person. Mental disease is often accompanied by factors increasing the social exclusion and discrimination of patients. Another problem is deeply rooted stereotypes and prejudices functioning in the public opinion, according to which people who suffer from mental disorder are considered insane and often dangerous for society. In Poland, thanks to, amongst others, the ESF (The European Social Fund) funds, it is possible to finance and implement research concerning social exclusion and discrimination of people who have experienced a mental crisis. The aim of the study was to evaluate the level of social exclusion and discrimination of people suffering from mental disorders from the Lodz region on the basis of seven points scale assessing their personal, occupational, and social functioning. MATERIAL AND METHODS; The study included a group of 101 patients with mental disorders. Participants were selected randomly from mental health institutions from the region of Lodz. To evaluate the problem of social exclusion in the group of patients a interview questionnaire was used. Social exclusion concerned people suffering from schizophrenia and psychosis, more than six years of illness, those with allocated disability pension, non-working and non-learning, with the lowest levels of education and maintaining a one-person household or living with one parent. Those who experienced the lowest degree of social exclusion were mainly people suffering from mood disorders, people with higher education, learning and working, living with both parents. Groups experiencing discrimination were mostly people with schizophrenia, disorders due to psychoactive substances, those with secondary and professional education, patients having a certificate of disability and maintaining a one-person household. Social exclusion of mentally ill people was mainly related to their low education, civic, social and economic activity. The problem of discrimination concerned 17% of the tested group. Half of participants of the study did not experience the discrimination effect.

Linking numerical models of lithospheric deformation and magnetotelluric images

NASA Astrophysics Data System (ADS)

Sobolev, S. V.

2012-12-01

Efficient modeling of geodynamic processes requires constraints from different fields of geosciences. Frequently used are data on crustal structure and composition and their evolution constrained by seismic, gravity and petrological/geochemical studies. However, links between geodynamic modeling and rapidly developing field of magnetotelluric (MT) studies are still insufficient. I'll consider two recent examples of MT observations and geodynamic modeling demonstrating that joint analyses of thermomechanical models of lithospheric deformation and MT images may be useful to understand geodynamic processes. One set of observations is MT data for San Andreas Fault (SAF) in the region close to the SAFOD Site (Becken et al., 2011) that shows high conductivity anomalies in the mantle, that are interpreted as fluid flow feeding creeping part of SAF south of the SAFOD Site. Interestingly, zones of high conductivity do not coincide with the expected zones of the recent active deformation (SAF), but are located to the west of it. Based on thermomechanical model of the evolution of the SAFS in Central and Northern California during the last 20 Mln. years (Popov et al., 2012), I'll demonstrate that high conductivity anomalies precisely coincide with the expected zones of the highest accumulated shear strain. Possible interpretation of this coincidence is that strong preferred orientation of olivine crystals in the highly deformed mantle shear zone causes high permeability of fluids. Another set of observations is MT data showing high conductivity anomalies in the crust of Tibet (Unsworh et al., 2005, Bai et al., 2010) and Pamirs (Sass et al., 2011) that are often interpreted as an evidence for the widely spread partially molten crust. Using 2D thermomechanical models of the collision between India and Eurasia, I'll demonstrate that such structures in the crust cannot appear without delamination of the mantle lithosphere during tectonic shortening. Internal heating of the thickened felsic crust due to radiogenic heat production and shear heating is not sufficient to produce such structures. The key triggering factor for the delamination is gabbro-eclogite transformation in the lower crust. Delamination of the lower crust and mantle lithosphere is followed by the partial melting and internal convection in the thickened upper-middle crust.

Preventing heat-related morbidity and mortality: new approaches in a changing climate.

PubMed

O'Neill, Marie S; Carter, Rebecca; Kish, Jonathan K; Gronlund, Carina J; White-Newsome, Jalonne L; Manarolla, Xico; Zanobetti, Antonella; Schwartz, Joel D

2009-10-20

Due to global climate change, the world will, on average, experience a higher number of heat waves, and the intensity and length of these heat waves is projected to increase. Knowledge about the implications of heat exposure to human health is growing, with excess mortality and illness occurring during hot weather in diverse regions. Certain groups, including the elderly, the urban poor, and those with chronic health conditions, are at higher risk. Preventive actions include: establishing heat wave warning systems; making cool environments available (through air conditioning or other means); public education; planting trees and other vegetation; and modifying the built environment to provide proper ventilation and use materials and colors that reduce heat build-up and optimize thermal comfort. However, to inspire local prevention activities, easily understood information about the strategies' benefits needs to be incorporated into decision tools. Integrating heat health information into a comprehensive adaptation planning process can alert local decision-makers to extreme heat risks and provide information necessary to choose strategies that yield the largest health improvements and cost savings. Tools to enable this include web-based programs that illustrate effective methods for including heat health in comprehensive local-level adaptation planning; calculate costs and benefits of several activities; maps showing zones of high potential heat exposure and vulnerable populations in a local area; and public awareness materials and training for implementing preventive activities. A new computer-based decision tool will enable local estimates of heat-related health effects and potential savings from implementing a range of prevention strategies.

Respiratory illness caused by overheating of polyvinyl chloride.

PubMed Central

Froneberg, B; Johnson, P L; Landrigan, P J

1982-01-01

On 9 August 1979, 62 (30.8%) of 201 workers and one of 60 management personnel in a polyvinyl chloride (PVC) fabricating plant developed acute upper and lower respiratory irritation, headache, nausea, and fainting. All were taken to hospital; none died. Sixty of the patients were women. Interviews two weeks later with 57 affected and 14 unaffected workers disclosed that illness had followed exposure to fumes from an overheated (362 degrees C) PVC extruding machine. Fumes were emitted from 1100 until 1150; cases occurred from 1100 until late afternoon. All workers who became ill worked west of the overheated extruder, and the affected manager had visited that area. The earliest cases occurred closest to the machine, and incidence decreased (from 53.3% to 15.4%) with distance westward. This pattern was consistent with plant ventilation. Incidence rates in men and women did not differ (p greater than 0.1). At two and 14 weeks, pulmonary function testing of workers with persistent pulmonary symptoms showed abnormalities in 13 of 16 and in 9 of 11 respectively; the group with persistent symptoms contained an excess of non-smokers and of those with previous respiratory illnesses. One kilogram of PVC heated to 300 degrees C releases an estimated 12.9 g of hydrochloric acid (HCl) and 4.9 g of carbon monoxide (CO). We attributed the outbreak to exposure to toxic HCl and CO and rejected the hypothesis of mass psychogenic illness. PMID:7093150

Nutritional Status Driving Infection by Trypanosoma cruzi: Lessons from Experimental Animals

PubMed Central

Malafaia, Guilherme; Talvani, André

2011-01-01

This paper reviews the scientific knowledge about protein-energy and micronutrient malnutrition in the context of Chagas disease, especially in experimental models. The search of articles was conducted using the electronic databases of SciELO (Scientific Electronic Library Online), PubMed and MEDLINE published between 1960 and March 2010. It was possible to verify that nutritional deficiencies (protein-energy malnutrition and micronutrient malnutrition) exert a direct effect on the infection by T. cruzi. However, little is known about the immunological mechanisms involved in the relationship “nutritional deficiencies and infection by T. cruzi”. A hundred years after the discovery of Chagas disease many aspects of this illness still require clarification, including the effects of nutritional deficiencies on immune and pathological mechanisms of T. cruzi infection. PMID:21577255

Management of climatic heat stress risk in construction: a review of practices, methodologies, and future research.

PubMed

Rowlinson, Steve; Yunyanjia, Andrea; Li, Baizhan; Chuanjingju, Carrie

2014-05-01

Climatic heat stress leads to accidents on construction sites brought about by a range of human factors emanating from heat induced illness, and fatigue leading to impaired capability, physical and mental. It is an occupational characteristic of construction work in many climates and the authors take the approach of re-engineering the whole safety management system rather than focusing on incremental improvement, which is current management practice in the construction industry. From a scientific viewpoint, climatic heat stress is determined by six key factors: (1) air temperature, (2) humidity, (3) radiant heat, and (4) wind speed indicating the environment, (5) metabolic heat generated by physical activities, and (6) "clothing effect" that moderates the heat exchange between the body and the environment. By making use of existing heat stress indices and heat stress management processes, heat stress risk on construction sites can be managed in three ways: (1) control of environmental heat stress exposure through use of an action-triggering threshold system, (2) control of continuous work time (CWT, referred by maximum allowable exposure duration) with mandatory work-rest regimens, and (3) enabling self-paced working through empowerment of employees. Existing heat stress practices and methodologies are critically reviewed and the authors propose a three-level methodology for an action-triggering, localized, simplified threshold system to facilitate effective decisions by frontline supervisors. The authors point out the need for "regional based" heat stress management practices that reflect unique climatic conditions, working practices and acclimatization propensity by local workers indifferent geographic regions. The authors set out the case for regional, rather than international, standards that account for this uniqueness and which are derived from site-based rather than laboratory-based research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Control of Thermal Meat Processing

NASA Astrophysics Data System (ADS)

Griffis, Carl L.; Osaili, Tareq M.

The recent growth of the market for ready-to-eat (RTE) meat and poultry products has led to serious concern over foodborne illnesses due to the presence of pathogens, particularly Salmonella spp, Listeria monocytogenes and Escherichia coli O157:H7 in meat and poultry products. Emphasis has been placed on thermal processing since heat treatment is still considered the primary means of eliminating foodborne pathogens from raw meat and poultry products (Juneja, Eblen, & Ransom, 2001). Inadequate time/temperature exposure during cooking is a contributing factor in food poisoning outbreaks. Optimal heat treatment is required not only to destroy pathogenic microorganisms in meat and poultry products but also to maintain desirable food quality and product yield.

Cardiovascular adaptations supporting human exercise-heat acclimation.

PubMed

Périard, Julien D; Travers, Gavin J S; Racinais, Sébastien; Sawka, Michael N

2016-04-01

This review examines the cardiovascular adaptations along with total body water and plasma volume adjustments that occur in parallel with improved heat loss responses during exercise-heat acclimation. The cardiovascular system is well recognized as an important contributor to exercise-heat acclimation that acts to minimize physiological strain, reduce the risk of serious heat illness and better sustain exercise capacity. The upright posture adopted by humans during most physical activities and the large skin surface area contribute to the circulatory and blood pressure regulation challenge of simultaneously supporting skeletal muscle blood flow and dissipating heat via increased skin blood flow and sweat secretion during exercise-heat stress. Although it was traditionally held that cardiac output increased during exercise-heat stress to primarily support elevated skin blood flow requirements, recent evidence suggests that temperature-sensitive mechanisms may also mediate an elevation in skeletal muscle blood flow. The cardiovascular adaptations supporting this challenge include an increase in total body water, plasma volume expansion, better sustainment and/or elevation of stroke volume, reduction in heart rate, improvement in ventricular filling and myocardial efficiency, and enhanced skin blood flow and sweating responses. The magnitude of these adaptations is variable and dependent on several factors such as exercise intensity, duration of exposure, frequency and total number of exposures, as well as the environmental conditions (i.e. dry or humid heat) in which acclimation occurs. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Medical support for Operation Cooperative Nugget '95: joint readiness training in the post-cold war era.

PubMed

Jerant, A F; Epperly, T D; Marionneaux, R D

1997-11-01

The purpose of this paper is to report the demographic characteristics, injury and illness profiles, and dispositions of patients seen at the 249th General Hospital during its month-long deployment in support of Operation Cooperative Nugget '95 at the Joint Readiness Training Center (JRTC), Fort Polk, Louisiana. A descriptive analysis of patient demographic, diagnostic, and disposition data was performed. A total of 769 patient contacts were made, with orthopedic injuries (31%), dermatologic disorders (17%), upper respiratory infections (6%), and heat injuries (5%) accounting for the majority of visits. Because of aggressive preventive medicine interventions, there were no cases of heat stroke despite daily heat indices of 110 to 120 degrees F. In addition to emphasizing the importance of anticipating environmental medical threats, the authors relate some lessons learned, which should be valuable to medical providers tasked for future multinational operations other than war at the JRTC and elsewhere.