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A popular belief states that if frog is submerged in a container and gradually heats it up, it will try to adapt until it dies; this is probably the situation faced by more and more human populations. As stated by thousands of scientists, academics, and researchers worldwide, the planet's warming is directly related to climate change.

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Desert shrubs are keystone species for plant diversity and ecosystem function. Atriplex clivicola and Atriplex deserticola (Amaranthaceae) are native shrubs from the Atacama Desert that show contrasting altitudinal distribution (A. clivicola: 0-700 m.a.s.l.; A. deserticola: 1500-3000 m.a.s.l.). Both species possess a C4 photosynthetic pathway and Kranz anatomy, traits adaptive to high temperatures. Historical records and projections for the near future show trends in increasing air temperature and frequency of heat wave events in these species' habitats. Besides sharing a C4 pathway, it is not clear how their leaf-level physiological traits associated with photosynthesis and water relations respond to heat stress. We studied their physiological traits (gas exchange, chlorophyll fluorescence, water status) before and after a simulated heat wave (HW). Both species enhanced their intrinsic water use efficiency after HW but via different mechanisms. A. clivicola, which has a higher LMA than A. deserticola, enhances water saving by closing stomata and maintaining RWC (%) and leaf Ψmd potential at similar values to those measured before HW. After HW, A. deserticola showed an increase of Amax without concurrent changes in gs and a significant reduction of RWC and Ψmd. A. deserticola showed higher values of Chla fluorescence after HW. Thus, under heat stress, A. clivicola maximizes water saving, whilst A. deserticola enhances its photosynthetic performance. These contrasting (eco)physiological strategies are consistent with the adaptation of each species to their local environmental conditions at different altitudes.

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Ectotherms, such as insects, are susceptible to climate changes because their body temperature is not physiologically regulated. Forecasts indicate a worldwide temperature rise of 1.4-6 °C by 2100, and an increase in heatwave frequency is expected. This study investigated the effects of constant temperatures (CT; 27, 34, 39, 40 and 41 °C) and fluctuating temperature (FT; 27/34 °C: 12/12 h) on the survival, metabolic rate, locomotor activity, gas exchange pattern, heat loss and water content of the male Jamaican field cricket, Gryllus assimilis (Fabricius, 1775) (Orthoptera: Gryllidae). It was found that 39 °C was the estimated lethal temperature for 50% of the population and that 41 °C was considered the thermal limit, causing 100% mortality in 96 h. Furthermore, FT caused slightly higher mortality (8.9 ± 3.8%) than CT27 (0%) and CT34 (1.43 ± 1.43%). FT caused a greater increase in the metabolic rate and locomotor activity than CT27. It was found that G. assimilis males had a continuous gas exchange as a standard at CT27; however, CT34 changed the gas exchange pattern from continuous to cyclic in 27% of crickets. FT decreased heat loss in crickets more than CT34; however, no significant differences were found in locomotor activity and metabolic rate. In addition, no significant differences between CT27, CT34 and FT were observed in terms of water content, thus suggesting no difference in water loss. Thus, it is suggested that FT, despite involving a modest warming, increased the climate sensitivity of G. assimilis males and led to a change in their optimum temperature, pushing it beyond its usual thermal limits. However, higher mortality in FT compared to CT27 (control) and CT34 must be interpreted with caution. In addition, the risk of higher mortality of G. assimilis males is predicted, especially in South America, where this cricket is widely distributed.

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The impact of heat waves and cold spells on mortality has become a major public health problem worldwide, especially among older adults living in low-to middle-income countries. This study aimed to investigate the effects of heat waves and cold spells under different definitions on cause-specific mortality among people aged ≥65 years in São Paulo from 2006 to 2015. A quasi-Poisson generalized linear model with a distributed lag model was used to investigate the association between cause-specific mortality and extreme air temperature events. To evaluate the effects of the intensity under different durations, we considered twelve heat wave and nine cold spell definitions. Our results showed an increase in cause-specific deaths related to heat waves and cold spells under several definitions. The highest risk of death related to heat waves was identified mostly at higher temperature thresholds with longer events. We verified that men were more vulnerable to die from cerebrovascular diseases and ischemic stroke on cold spells and heat waves days than women, while women presented a higher risk of dying from ischemic heart diseases during cold spells and tended to have a higher risk of chronic obstructive pulmonary disease than men during heat waves. Identification of heat wave- and cold spell-related mortality is important for the development and promotion of public health measures.

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Introdução: A exposição nociva ao calor ganha mais relevância com a progressão do aquecimento global antropogênico e a Atenção Primária à Saúde (APS) tem um papel crescente nesse cenário. No Brasil, as ondas de calor entre 2014 e 2015 duraram mais tempo que nos anos prévios, além disso, entre 2000-2015 a associação entre temperatura e hospitalizações variou de acordo com a duração da exposição ao calor. Nesse contexto, o objetivo desta revisão é realizar uma atualização sobre manejo clínico de patologias relacionadas ao calor na APS. Metodologia: Realizou-se a busca na base de dados ACCESSS, que utiliza a pirâmide 5.0 da assistência à saúde baseada em evidências. Foram identificados 103 sumários sintetizados para referência clínica com as palavras "Heat stress", "Heat Stroke", "Heat Wave" e "Heat Exhaustion", mas apenas três entravam no escopo deste estudo. Resultados e Discussão: O estresse pelo calor é uma condição comum, negligenciada e evitável que afeta diversos pacientes, iniciando-se com uma má adaptação ao calor que se não for corrigida pode gerar uma cascata de eventos inflamatórios. O estresse pelo calor é caracterizado por sintomas inespecíficos, como mal-estar, cefaleia e náusea. O tratamento envolve o resfriamento do paciente e monitoramento, garantindo hidratação adequada. A exaustão pelo calor, se não tratada, pode evoluir para insolação, uma doença grave que pode levar ao coma e morte, envolvendo disfunção do sistema nervoso central - necessitando de um tratamento mais agressivo além do resfriamento

Introduction: The nocive exposure to heat gets more attention with anthropogenic global warming, and Primary Health Care (PHC) has a growing role in this scenario. In Brazil heat waves between 2014 and 2015 lasted longer than in previous years. Further, in addition between 2000-2015 the association between temperature and hospitalizations varied according to the duration of heat exposure. Therefore, the aim of this review is to perform an update on clinical management of heat related pathologies in PHC. Methodology: The ACCESSS database was searched using the evidence-based health care pyramid 5.0, where we identified 103 synthesized summaries for clinical reference with words "Heat stress", "Heat Stroke", "Heat Wave" and "Heat Exhaustion", but only three fell within the scope of this study. Results and Discussion: Heat stress is a common, neglected and preventable condition that affects several patients, it starts with a poor adaptation to heat that if it is not adjusted it can generate a cascade of inflammatory events. Heat stress is characterized by nonspecific symptoms such as malaise, headache and nausea. The treatment involves patient monitoring and cooling, ensuring adequate hydration. Heat exhaustion, if untreated, can progress to heatstroke, a serious illness that can lead to coma and death, involving central nervous system dysfunction - requiring more aggressive treatment than cooling.

Introducción: La exposición nociva al calor gana más destaque con la progresión del calentamiento global antropogénico, y la Atención Primaria a la Salud tienen un papiel cresciente en este escenario. En Brasil las olas de calor entre 2014 y 2015 duraron más tiempo que en los años previos, además entre 2000-2015 la asociación entre temperatura y hospitalizaciones ha variado de acuerdo con la duración de la exposición al calor. En este contexto, el objetivo de esta revisión es realizar una actualización sobre manejo clínico de patologías relacionadas al calor en la APS. Metodología: Se realizó la búsqueda en la base de datos ACCESSS, que utiliza la pirámide 5.0 de la asistencia a la salud basada en evidencias. Se han identificado 103 sumarios sintetizados para referencia clínica con las palabras "Heat stress", "Heat Stroke", "Heat Wave" y "Heat Exhaustion", pero sólo tres son considerados en el ámbito de este estudio. Resultados y Discusión: El estrés por el calor es una condición común, descuidada y evitable que afecta a varios pacientes, iniciándose con una mala adaptación al calor que si no se corrige puede generar una cascada de eventos inflamatorios. El estrés por el calor se caracteriza por síntomas inespecíficos, como malestar, cefalea y náuseas. El tratamiento implica el enfriamiento del paciente y el monitoreo, garantizando la hidratación adecuada. El agotamiento por el calor, si no se trata, puede evolucionar hacia la insolación, una enfermedad grave que puede llevar al coma y a la muerte, involucrando disfunción del sistema nervioso central - necesitando un tratamiento más agresivo además del enfriamiento.

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Objective To describe the case of a patient with schizophrenia on clozapine treatment who had an episode of heat stroke. Case description During a heat wave in January and February 2014, a patient with schizophrenia who was on treatment with clozapine was initially referred for differential diagnose between systemic infection and neuroleptic malignant syndrome, but was finally diagnosed with heat stroke and treated with control of body temperature and hydration. Comments This report aims to alert clinicians take this condition into consideration among other differential diagnoses, especially nowadays with the rise in global temperatures, and to highlight the need for accurate diagnosis of clinical events during pharmacological intervention, in order to improve treatment decisions and outcomes.

Objetivo Descrever o caso de um paciente com esquizofrenia em tratamento com clozapina acometido por um episódio de heat stroke. Descrição do caso Durante uma onda de calor em janeiro e fevereiro de 2014, um paciente com esquizofrenia em tratamento com clozapina foi inicialmente encaminhado para diagnóstico diferencial de infecção sistêmica e síndrome neuroléptica maligna, tendo obtido o diagnóstico final de heat stroke, tratado com controle de temperatura corporal e hidratação. Comentários Este relato de caso tem como objetivo alertar os clínicos para este diagnóstico diferencial, que pode surgir com mais frequência à medida que as temperaturas globais continuarem a aumentar, e também destacar a importância da realização de um diagnóstico mais acurado, que possa melhorar as decisões de tratamento e os desfechos clínicos para os pacientes.

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Climate may affect broiler production, especially where there are heat waves, which may cause high mortality rates due to the heat stress. Heat wave prediction and characterization may allow early mitigation actions to be taken. Data Mining is one of the tools used for such a characterization, particularly when a large number of variables is involved. The objective of this study was to classify heat waves that promote broiler chicken mortality in poultry houses equipped with minimal environmental control. A single day of heat, a heat-shock day, is capable of producing high broiler mortality. In poultry houses equipped with fans and evaporative cooling, the characterization of heat waves affecting broiler mortality between 29 days of age and market age presented 89.34% Model Accuracy and 0.73 Class Precision for high mortality. There was no influence on high mortality (HM) of birds between 29 and 31 days of age. Maximum temperature humidity index (THI) above 30.6 ºC was the main characteristic of days when there was a heat wave, causing high mortality in broilers older than 31 days. The high mortality of broilers between 31 and 40 days of age occurred when maximum THI was above 30.6 ºC and maximum temperature of the day was above 34.4 ºC. There were two main causes of high mortality of broilers older than 40 days: 1) maximum THI above 30.6 ºC and minimum THI equal or lower than 15.5 ºC; 2) maximum THI above 30.6 ºC, minimum THI lower than 15.5 ºC, and the time of maximum temperature later than 15:00h. The heat wave influence on broiler mortality lasted an average of 2.7 days.

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Climate may affect broiler production, especially where there are heat waves, which may cause high mortality rates due to the heat stress. Heat wave prediction and characterization may allow early mitigation actions to be taken. Data Mining is one of the tools used for such a characterization, particularly when a large number of variables is involved. The objective of this study was to classify heat waves that promote broiler chicken mortality in poultry houses equipped with minimal environmental control. A single day of heat, a heat-shock day, is capable of producing high broiler mortality. In poultry houses equipped with fans and evaporative cooling, the characterization of heat waves affecting broiler mortality between 29 days of age and market age presented 89.34% Model Accuracy and 0.73 Class Precision for high mortality. There was no influence on high mortality (HM) of birds between 29 and 31 days of age. Maximum temperature humidity index (THI) above 30.6 ºC was the main characteristic of days when there was a heat wave, causing high mortality in broilers older than 31 days. The high mortality of broilers between 31 and 40 days of age occurred when maximum THI was above 30.6 ºC and maximum temperature of the day was above 34.4 ºC. There were two main causes of high mortality of broilers older than 40 days: 1) maximum THI above 30.6 ºC and minimum THI equal or lower than 15.5 ºC; 2) maximum THI above 30.6 ºC, minimum THI lower than 15.5 ºC, and the time of maximum temperature later than 15:00h. The heat wave influence on broiler mortality lasted an average of 2.7 days.