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BACKGROUND: Low temperatures are adverse contributors to cardiovascular diseases, but the associations between short-term exposure to cold and the risk of death from aortic dissection and aneurysm remain unclear, particularly in tropical regions. OBJECTIVE: This study was conducted based on 123,951 records of deaths caused by aortic dissection and aneurysms extracted from the national Mortality Information System in Brazil between 2000 and 2019. METHODS: Relative risks and 95 % confidence intervals (CI) for the aortic-related deaths associated with low ambient temperatures were estimated using the conditional logistic model combined with the distributed lag nonlinear model. Subgroup analyses were performed by age group, sex, race, education level, and residential region. Furthermore, this study calculated the number and fraction of aortic-related deaths attributed to temperatures below the temperature threshold to quantify the cold-related mortality burden of aortic diseases. RESULTS: During the study period, aortic-related deaths and mortality rates in Brazil exhibited a steady increase, rising from 4419 (2.66/100,000) in 2000 to 8152 (3.88/100,000) in 2019. Under the identified temperature threshold (26 °C), per 1 °C decrease in daily mean temperature was associated with a 4.77 % (95 % CI: 4.35, 5.19) increase in mortality risk of aortic-related diseases over lag 0-3 days. Females, individuals aged 50 years or older, Asian and Black race, and northern residents were more susceptible to low temperatures. Low temperatures were responsible for 19.10 % (95 % CI: 17.71, 20.45) of aortic-related deaths in Brazil. CONCLUSION: This study highlights that low temperatures were associated with an increased risk of aortic-related deaths, with a remarkable burden even in this predominantly tropical country.

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Daily torpor allows endotherms to save energy during energetically stressful (e.g. cold) conditions. Although studies on avian torpor have mostly been conducted under laboratory conditions, information on the usage of torpor in the wild is limited to few, predominantly temperate-zone species. We studied torpor under seminatural conditions from 249 individuals from 29 hummingbird species across a 1920 m elevational gradient in the western Andes of Colombia using cloacal thermistors. Small birds were more likely to use torpor than large birds, but only at low ambient temperatures, where torpor was prolonged. We also found effects of proxy variables for body condition and energy expenditure on the use of torpor, its characteristics, and impacts. Our results suggest that context-dependency and phylogenetic variation in the probability of deploying torpor can help understand clade-wide patterns of elevational distribution in Andean hummingbirds.

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This study investigated the effects of a low-protein diet with or without an increase in dietary protein and feed-grade amino acids (AAs) on the growth performance, body composition, metabolism, and serum acute-phase proteins of finishing pigs reared in thermoneutrality or cyclic heat stress conditions. A total of 90 gilts (67.7 ± 6.2 kg) were distributed in a 2 × 3 factorial arrangement (two ambient temperatures and three diets). Ambient temperatures (AT) were thermoneutral (TN, 22 °C for 24 h) and cyclic heat stress (CHS, 12 h to 35 °C and 12 h to 22 °C). The evaluated diets (D) were high crude protein (HP); low CP-free AA-supplemented diets (LPAAs); low CP-free AA-supplemented diets and digestible Lys level (+20%), and Lys:AA ratios above recommendations (LPAA+). The experimental period lasted 48 d (two experimental phases: days 0-27 and days 28-48, respectively). CHS pigs had higher skin temperature (P < 0.05) than TN pigs. Pigs in CHS had higher rectal temperature (P < 0.05) than TN pigs until day 38 but similar (P > 0.10) to TN pigs from 38 to 45 d. For the entire experiment, CHS pigs had lower (P < 0.05) final BW, average daily gain and daily feed intake, net energy intake, body lipid, bone mineral, lipid deposition, energy retention, Lys and CP intake, and nitrogen excretion than TN pigs. The level of CP intake impacted nitrogen excretion, nitrogen retention efficiency, and urea as pigs fed HP had the highest values, and pigs fed LPAA had the lowest values (P < 0.05). On day 27, CHS pigs had lower (P < 0.05) free triiodothyronine than TN pigs. LPAA+ pigs had lower (P < 0.05) insulin than LPAA. On day 48, CHS pigs had lower (P < 0.05) thyroxine, albumin, and lactate than TN pigs. On day 27, pigs fed LPAA+ had higher (P < 0.05) lactate than pigs fed HP or LPAA. Both AT and D were enough to stimulate the immune system as CHS pigs had lower (P < 0.05) transferrin and 23-kDa protein levels than TN pigs, and HP pigs had higher haptoglobin than LPAA on day 27. These results confirm the deleterious effects of high AT on performance, body composition, metabolism, and immune system stimulation in finishing pigs. These data also show that a diet with low levels of CP can be provided to pigs in CHS without affecting performance and body composition while reducing nitrogen excretion. However, the use of a diet with an AA level above the requirements obtained by increasing intact protein and free AA did not attenuate the impact of CHS on performance and body composition of pigs.

High ambient temperature and air humidity are the most important climatic factors that jeopardize pig production. Multiple strategies can be applied for pigs under heat stress, including recent research to improve understanding the use of nutrition to attenuate the impact of heat stress. Heat stress impairs digestion, absorption, and amino acid metabolism with changes in amino acid requirements. Updates on the nutritional assessment strategies by differing the diets by protein and amino acid content (protein-bound or feed-grade) seem to be efficient tools for pork producers as amino acids play a functional role in challenged pigs apart from the beneficial effects on performance.

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Detection of residual formaldehyde (FA) in dairy products could be explained by direct addition of this preservative to extend the shelf life of raw material or final product at room temperature. FA is not authorized as a preservative by international standards and its addition to dairy products is prohibited due to its potentially harmful effects on consumers. Although the carcinogenicity of FA by oral exposure has not been proven, it is also known it cause histopathological and cytogenic changes in tissues at first contact, so its toxicity by ingestion should not be underestimated. This research determined both residual FA levels in locally produced fresh white cheese and its variation according to the seasons of the year and its association with ambient temperature. None of the FA levels quantified in cheese exceeded the maximum tolerable concentration (2.6 mg/kg) and although average FA contents did not vary significantly with seasonal changes (0.093-0.181 mg/kg), the number of positive cases did, since the highest prevalence occurred in the dry (60.9 %) and transitional dry-rainy (79.7 %) seasons of 2021, which are characterized by having the highest average ambient temperatures (27.5 °C and 28.3 °C, respectively). It was also shown that 79.6 % of the variability of FA-positive samples is explained by changes in the average temperature according to the year´s season. The association between these variables and quantified levels of aldehyde in raw milk sampled at the plant could indicate that FA was used to prevent milk and/or the final product from decomposing due to the effect of high ambient temperature. In addition, residual FA contents decreased in both milk and cheese, depending on added preservative levels, and the time elapsed prior to analysis.

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Exposure to ambient temperature has been linked to adverse birth outcomes in several regions, including the USA, Australia, China, countries in the Middle East, and European countries. To date, no studies were performed in South America, a region with serious challenges related to climate change. Our investigation addresses this literature lack by examining the association between Low Birth Weight (LBW) and ambient temperature exposure in the largest county in South America, Brazil. We applied a nationwide case-control study design using a logistic regression model to estimate the odds ratio (OR) for LBW associated with ambient temperature during a specific trimester of pregnancy (1-3 trimester). Our sample size includes 5,790,713 birth records nationwide over 18 years (2001-2018), of which 264,967 infants were included in the model as cases of LBW, representing 4.6% of our total sample. We adjusted our model for several confounding variables, including weather factors, air pollution, seasonality, and SES variables at the individual level. Our findings indicate that North was the only region with positive and statistically significant associations in the primary analysis and most of the sensitivity analysis, which is the region where the Amazon is located. In this region, we estimated an increase of 5.16% (95%CI: 3.60; 6.74) in the odds of LBW per 1 °C increase in apparent temperature when the exposure occurred in the second trimester. Our results may be explained by the climate conditions in the Amazon region in the past years. A large body of literature indicates that the Amazon region has been facing serious climate challenges including issues related to policy, governance, and deforestation. Specifically, regarding deforestation, it is suggested that land use change and deforestation is projected to increase heat stress in the Amazon region, because of Amazon savannization, increasing the risk of heat stress exposure in Northern Brazil. Our study can assist public sectors and clinicians in mitigating the risk and vulnerability of the Amazonian population.

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BFS-MK-based alkali-activated materials are well established as an alternative for sustainable and green construction. This work aims to collaborate and encourage the use of biomass ashes, such as sugarcane bagasse ash (SCBA), as a precursor in alkali-activated materials (AAM). This ash is a rich source of aluminosilicate, which is a primary requirement for this application. In addition, this waste is still an environmental liability, especially in developing countries, and with a large volume of annual production. Thus, in this research, alkali-activated pastes (AA) were produced using sugarcane bagasse ash (SCBA), granulated blast furnace slag (BFS) and metakaolin (MK) as precursors. In addition, environmental gains were encouraged with energy savings, with no extra reburn or calcination steps in the SCBA. Thus, the precursors were characterized by laser granulometry, X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The pastes were produced by mixing the precursors with the activator, composed of a mixture of sodium hydroxide 8 mol/L and sodium silicate. Aiming to study the incorporation of SCBA, all samples have a precursor/activator ratio and a BFS/(BFS + MK) ratio constant of 0.6. The compressive strength analysis, FTIR, XRD, TGA, SEM and isothermal calorimetry analyses pointed out the occurrence of alkaline activation in all proposed samples for curing times of 7, 28 and 91 days. The sample GM0.6-BA0 (15% SCBA) achieved the highest compressive strength among the samples proposed (117.7 MPa, at 91 days), along with a good development of strength throughout the curing days. Thus, this work presents the properties of alkaline-activated pastes using SCBA as a sustainable and alternative precursor, seeking to encourage the use of raw materials and alternative waste in civil construction.

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ABSTRACT: Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.

RESUMO: A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.

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Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.

A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.

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The objective of this study was to assess the effect of ambient temperature (T) and feeding time (FT) on eggshell thickness (ST) and egg weight (EW) of broiler breeder hens. Thirty 44-week-old Ross 308 broiler breeder hens were randomly distributed into six environmentally controlled chambers and kept in individual cages. Three thermal treatments were applied: 20 ºC (T1), cyclic 20-30 ºC (30 °C between 1000 h and 1800 h) (T2), and 30 ºC (T3). Birds received 180 g of commercial breeder food at 0730 h (FT1) or 1530 h (FT2). There were two replications per treatment and egg collection was performed for seven days. The eggs from the birds at T1 and T2 fed at 1530 h (T1FT2 and T2FT2 respectively) were significantly heavier than those laid by hens at the same T when fed in the morning (T1FT1 and T2FT1); eggs from T1FT1 and T2FT1 were heavier than the eggs from T3, but there were no significant differences between them. Both T and FT had significant effects on ST, but no significant interactions were found. Birds fed at 1530 h had the highest ST, whilst birds at T3 showed the lowest. Birds on T2 produced the thickest shells due to a higher ST in birds fed at 1530 h. Birds fed at 1530 h consumed their food between 1800 h and 2030 h, resulting in a higher dietary Ca2 + available during shell mineralization. The effect of FT and biphasic T treatments on ST in feed restricted broiler breeders should be interpreted considering the length of the high T phase to the actual food consumption time.(AU)

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Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.(AU)

A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.(AU)

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KEY MESSAGE: Two class I TCP transcription factors are required for an efficient elongation of hypocotyls in response to auxin and for the correct expression of a subset of auxin-inducible genes In this work, we analyzed the response to auxin of plants with altered function of the class I TEOSINTE BRANCHED 1, CYCLOIDEA, PCF (TCP) transcription factors TCP14 and TCP15. Several SMALL AUXIN UP RNA (SAUR) genes showed decreased expression in mutant plants defective in these TCPs after an increase in ambient temperature to 29 °C, a condition that causes an increase in endogenous auxin levels. Overexpression of SAUR63 caused a more pronounced elongation response in the mutant than in the wild-type at 29 °C, suggesting that the decreased expression of SAUR genes is partly responsible for the defective elongation at warm temperature. Notably, several SAUR genes and the auxin response gene IAA19 also showed reduced expression in the mutant after auxin treatment, while the expression of other SAUR genes and of IAA29 was not affected or was even higher. Expression of the auxin reporter DR5::GUS was also higher in a tcp15 mutant than in a wild-type background after auxin treatment. However, the elongation of hypocotyls in response to auxin was impaired in the mutant. Remarkably, a significant proportion of auxin inducible genes and of targets of the AUXIN RESPONSE FACTOR 6 are regulated by TCP15 and often contain putative TCP recognition motifs in their promoters. Furthermore, we demonstrated that several among them are recognized by TCP15 in vivo. Our results indicate that TCP14 and TCP15 are required for an efficient elongation response to auxin, most likely by regulating a subset of auxin inducible genes related to cell expansion.

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BACKGROUND: Vertebrates exhibit diverse sex determination systems and reptiles stand out by having highly variable sex determinations that include temperature-dependent and genotypic sex determination (TSD and GSD, respectively). Theory predicts that populations living in either highly variable or cold climatic conditions should evolve genotypic sex determination to buffer the populations from extreme sex ratios, yet these fundamental predictions have not been tested across a wide range of taxa. RESULTS: Here, we use phylogenetic analyses of 213 reptile species representing 38 families (TSD = 101 species, GSD = 112 species) and climatic data to compare breeding environments between reptiles with GSD versus TSD. We show that GSD and TSD are confronted with the same level of climatic fluctuation during breeding seasons. However, TSD reptiles are significantly associated with warmer climates. We found a strong selection on the breeding season length that minimises exposure to cold and fluctuating climate. Phylogenetic path analyses comparing competing evolutionary hypotheses support that transitions in sex determination systems influenced the ambient temperature at which the species reproduces and nests. In turn, this interaction affects other variables such as the duration of the breeding season and life-history traits. CONCLUSIONS: Taken together, our results challenge long-standing hypotheses about the association between sex determination and climate variability. We also show that ambient temperature is important during breeding seasons and it helps explain the effects of sex determination systems on the geographic distribution of extant reptile species.

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In this century, climate change is one of the major problems affecting livestock productivity. This study aimed at evaluating the effect of body coat color pattern and sex on heat regulation and heat stress tolerance in indigenous goat breeds exposed to solar radiation. In the experiment, 4 bucks and 4 does (8 to 9 months age) with black, white, grey and browncoat color were selected and exposed to solar radiation during 12 days during the summer period. Water and feed were served add libitum. The consumption were measured daily at 17:00 for each animal. Rectal temperature (RT) and rate pulse (PR) were measured three-time (7:00, 12:00, and 17:00) every day on each animal during the experimental period. At the end of the experiment, blood samples were collected from the jugular vein and immediately delivered to the lab to determinebiochemical (serum protein: albumin and globulin), and hematological parameters. Exposing goats to temperature variation affected the physiological, hematological as well as biochemical parameters in all subjects. The female with a black body coat color was mostly affected. The heat stress induced an increase of RT and PR, an increase in waterconsumption while depression in food intake was observed. Blood platelets, hematocrits, red cell distribution, white blood cell and albumin were damaged in goats with black coat color compared to goats with white coat color. These variations in physiological, hematological and biochemical parameters in female black goat could affect its productive and reproductive performances in high-temperature environments.

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In this century, climate change is one of the major problems affecting livestock productivity. This study aimed at evaluating the effect of body coat color pattern and sex on heat regulation and heat stress tolerance in indigenous goat breeds exposed to solar radiation. In the experiment, 4 bucks and 4 does (8 to 9 months age) with black, white, grey and browncoat color were selected and exposed to solar radiation during 12 days during the summer period. Water and feed were served add libitum. The consumption were measured daily at 17:00 for each animal. Rectal temperature (RT) and rate pulse (PR) were measured three-time (7:00, 12:00, and 17:00) every day on each animal during the experimental period. At the end of the experiment, blood samples were collected from the jugular vein and immediately delivered to the lab to determinebiochemical (serum protein: albumin and globulin), and hematological parameters. Exposing goats to temperature variation affected the physiological, hematological as well as biochemical parameters in all subjects. The female with a black body coat color was mostly affected. The heat stress induced an increase of RT and PR, an increase in waterconsumption while depression in food intake was observed. Blood platelets, hematocrits, red cell distribution, white blood cell and albumin were damaged in goats with black coat color compared to goats with white coat color. These variations in physiological, hematological and biochemical parameters in female black goat could affect its productive and reproductive performances in high-temperature environments.(AU)

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O aumento do risco relativo de mortalidade por diversas causas é associado a temperatura ambiente extremas. Fatores a nível individual e comunitários podem influenciar esta associação podendo aumentar ou diminuir seus efeitos. Estes podem ser variáveis ao longo do tempo, o que poderia fazer esta associação oscilar ao longo dos anos. Esta tese investigou os efeitos a curto prazo da temperatura ambiente na mortalidade da população geral e idosos do Brasil, bem como a modificação desta associação ao longo do tempo. O primeiro manuscrito verificou quais modificadores de efeito modulam a associação temperatura-mortalidade a curto prazo. O segundo manuscrito verificou se houve mudança na associação temperatura-mortalidade ao longo de três períodos sequenciais. Foi analisado mortalidade não-acidental da população geral e idosa, e para estes foi subdividido em causas circulatórias, respiratórias e outras causas. Ambos os estudos utilizaram um modelo aditivo generalizado combinado com distributed lag non-linear models e período de defasagem de 21 dias para estimar a associação temperatura-mortalidade para cada região metropolitana, grupo e período. Os estudos incluíram um teste de heterogeneidade entre os locais e estimativas combinadas para Brasil e regiões geográficas via metanálise. Modelos de metarregressão incluindo fatores a nível do local foram utilizados para análise de possíveis modificadores da associação. Os resultados do primeiro manuscrito evidenciam um efeito do frio e do calor na mortalidade não-acidental da população geral e idosa, bem como para mortalidade cardiovascular, respiratória e outras causas dos idosos do Brasil, principalmente nas regiões metropolitanas e geográficas do Sudeste e Sul do Brasil, sendo geralmente as baixas temperaturas as promotoras de maiores riscos relativos de óbitos. Os fatores geográficos foram os responsáveis por explicar a maior parte da heterogeneidade entre os locais, com destaque para amplitude da temperatura média. Os resultados do segundo manuscrito exibem estimativas pontuais de risco relativo de mortalidade associado ao frio e ao calor diferentes a cada quinquênio, sendo esta flutuação de padrões distintos conforme tipo de causa e região brasileira. A heterogeneidade da associação temperatura-mortalidade entre os locais cresceu ao longo dos períodos para todos os grupos. Nos grupos mortalidade não-acidental e circulatório, nos três períodos, a amplitude da temperatura é a variável que melhor explica esta heterogeneidade. No grupo respiratório a amplitude diária da temperatura foi forte explicador nos dois primeiros períodos. Os resultados desta tese sugerem efeito da temperatura ambiente sobre a mortalidade no Brasil, com maior foco nas regiões Sul e Sudeste. Assim, planejamento de ações com foco de adaptação as temperaturas extremas tanto altas quanto baixas são necessárias e de imediato foco nas regiões Sul e Sudeste.

The increase in the relative risk of mortality from various causes is associated with extreme ambient temperatures. Factors at the individual and community level can influence this association and may increase or decrease its effects. These can be variable over time, which could cause this association to fluctuate over the years. This thesis investigated the short-term effects of ambient temperature on mortality in the general population and the elderly in Brazil, as well as the modification of this association over time. The first manuscript verified which effect modifiers modulate the short-term association of temperature and mortality. The second manuscript verified whether there was a change in the association between temperature and mortality over three sequential periods. Non-accidental mortality of the general and elderly population was analyzed, and for these it was subdivided into circulatory, respiratory and other causes. Both studies used a generalized additive model combined with distributed lag non-linear models and a lag of 21 days, to estimate the temperature-mortality association for each metropolitan region, group and period. The studies included a test of heterogeneity between locations and combined estimates for Brazil and geographic regions via meta-analysis. Meta-regression models including factors at the local level were used to analyze possible modifiers of the association. The results of the first manuscript show an effect of cold and heat on non-accidental mortality in the general and elderly population, as well as for cardiovascular, respiratory and other causes of the elderly in Brazil, especially in the metropolitan and geographic regions of the Southeast and South of Brazil. Brazil, with low temperatures being generally the promoters of higher relative risks of death. The geographical factors were responsible for explaining most of the heterogeneity between the locations, with emphasis on the amplitude of the average temperature. The results of the second manuscript show specific estimates of the relative risk of mortality associated with cold and heat differently every five years, with this fluctuation of different patterns according to the type of cause and the Brazilian region. The heterogeneity of the temperature-mortality association between sites increased over the periods for all groups. In the non-accidental and circulatory mortality groups, in the three periods, the temperature amplitude is the variable that best explains this heterogeneity. In the respiratory group, the daily temperature range was a strong factor in the first two periods. The results of this thesis suggest the effect of ambient temperature on mortality in Brazil, with a greater focus on the South and Southeast regions. Thus, action planning with a focus on adaptation to extreme temperatures, both high and low, is necessary and immediately focus on the South and Southeast regions.

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Multi-city studies assessing the association between acute exposure to temperature and mortality in Latin American are limited. To analyze the short-term effect of changes in temperature (increase and decrease) on daily non-external and cardiovascular mortality from 1998 to 2014, in people 65 years old and over living in 10 metropolitan areas of Mexico. Analyses were performed through Poisson regression models with distributed lag non-linear models. Statistical comparison of minimum mortality temperature (MMT) and city-specific cutoffs of 24-h temperature mean values (5th/95th and 1st/99th percentiles) were used to obtain the mortality relative Risk (RR) for cold/hot and extreme cold/extreme hot, respectively, for the same day and lags of 0-3, 0-7, and 0-21 days. A meta-analysis was conducted to synthesize the estimates (RRpooled). Significant non-linear associations of temperature-mortality relation were found in U or inverted J shape. The best predictors of mortality associations with cold and heat were daily temperatures at lag 0-7 and lag 0-3, respectively. RRpooled of non-external causes was 6.3% (95%CI 2.7, 10.0) for cold and 10.2% (95%CI 4.4, 16.2) for hot temperatures. The RRpooled for cardiovascular mortality was 7.1% (95%CI 0.01, 14.7) for cold and 7.1% (95%CI 0.6, 14.0) for hot temperatures. Results suggest that, starting from the MMT, the changes in temperature are associated with an increased risk of non-external and specific causes of mortality in elderly people. Generally, heat effects on non-external and specific causes of mortality occur immediately, while cold effects occur within a few days and last longer.

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Plants respond to a rise in ambient temperature by increasing the growth of petioles and hypocotyls. In this work, we show that Arabidopsis thaliana class I TEOSINTE BRANCHED 1, CYCLOIDEA, PCF (TCP) transcription factors TCP14 and TCP15 are required for optimal petiole and hypocotyl elongation under high ambient temperature. These TCPs influence the levels of the DELLA protein RGA and the expression of growth-related genes, which are induced in response to an increase in temperature. However, the class I TCPs are not required for the induction of the auxin biosynthesis gene YUCCA8 or for auxin-dependent gene expression responses. TCP15 directly targets the gibberellin biosynthesis gene GA20ox1 and the growth regulatory genes HBI1 and PRE6. Several of the genes regulated by TCP15 are also targets of the growth regulator PIF4 and show an enrichment of PIF4- and TCP-binding motifs in their promoters. PIF4 binding to GA20ox1 and HBI1 is enhanced in the presence of the TCPs, indicating that TCP14 and TCP15 directly participate in the induction of genes involved in gibberellin biosynthesis and cell expansion by high temperature functionally interacting with PIF4. In addition, overexpression of HBI1 rescues the growth defects of tcp14 tcp15 double mutants, suggesting that this gene is a major outcome of regulation by both class I TCPs during thermomorphogenesis.

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Abstract Humidity is one of the most important ambient factors influencing torque calibration readings. The present study addresses the effects of relative humidity on the readings of reference torque transduction and amplification devices. The results revealed a linear effect of increasing humidity on the readings of a DMP40 torque amplifier and a torque transducer at different temperatures. Furthermore, humidity effects were smaller on the DMP40 amplifier than on the torque transducer, even at different temperatures. The results also showed that the summed effect of humidity changes on torque calibration readings of the amplifier and the torque transducer, when assessed simultaneously, but with each device under different controlled humidity conditions, is greater than the observed effect on the readings when both devices were subjected to humidity changes together. Therefore, it is recommended to test the effect of humidity in setups where these two devices are both under common humidity conditions. This is likely to lower the uncertainty parameter of the obtained torque calibration readings and is a useful consideration for inter-laboratory comparisons and performance testing.

Resumen La humedad es uno de los factores ambientales que más influyen sobre las lecturas de calibración de mediciones de torque. En este trabajo se estudiaron los efectos de la variación de la humedad relativa sobre las lecturas de aparatos de referencia para transducción y amplificación de torque. Los resultados mostraron una relación lineal y positiva entre el aumento de la humedad relativa y el componente de error de las mediciones de referencia de un transductor y un amplificador de torque DMP40 bajo cuatro temperaturas distintas. Sin importar la temperatura, las mediciones del transductor de torque fueron más susceptibles de ser afectadas por la humidad relativa que las del amplificador DMP40. Se observó también que la suma de los efectos de la humedad relativa en las lecturas de referencia del amplificador y el transductor fueron mayores cuando ambos aparatos fueron operados bajo condiciones de humedad relativa y temperatura distintas (i.e. el amplificador se encontraba en una cámara climática controlada y el transductor fuera de ella, y viceversa) que cuando ambos aparatos fueron operados bajo las mismas condiciones ambientales (i.e. ambos dentro de la cámara climática controlada). En consecuencia, se recomienda llevar a cabo evaluaciones de la humedad en espacios donde ambos aparatos estén bajo las mismas condiciones de temperatura y humedad relativa. Esto puede reducir el componente de incertidumbre de lecturas de calibración de torque y es un factor a considerar al llevar a cabo comparaciones entre laboratorios y tests de desempeño en aplicaciones industriales.

Resumo A umidade é um dos fatores ambientais que mais influenciam as leituras de calibração de medições de torque. O presente estudo analisou os efeitos da umidade relativa sobre as leituras de equipamentos de referência para transdução e amplificação de torque. Os resultados mostraram um efeito linear do aumento da umidade relativa na medição de referência de um transdutor e um amplificador de torque DMP40 em quatro temperaturas diferentes. Adicionalmente, os efeitos da umidade foram menores no amplificador DMP40 do que no transdutor de torque em todas as quatro temperaturas. Os resultados também mostraram que a soma dos efeitos da umidade relativa nas leituras de referência do amplificador e do transdutor foram maiores quando ambos equipamentos foram operados em condições de umidade relativa e temperatura distintas (p.e. o amplificador se encontrava em uma câmara climática controlada e o transdutor fora da câmara, e vice-versa) do que quando ambos equipamentos eram operados nas mesmas condições ambientais (p.e. ambos dentro da câmara climática controlada). Assim sendo, se recomenda avaliar o efeito da umidade em espaços onde ambos equipamentos estejam expostos a mesmas condições de temperatura e umidade relativa. Esso pode reduzir o parâmetro de incerteza das leituras de calibração de torque e é um fator a ser considerado ao realizar comparações entre laboratórios e testes de desempenho em aplicações industriais.

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The aim of the study was to evaluate the efficacy of a nutritional formulation based on amino acids and vitamins supplemented in the drinking water for chicks in the first week of life subjected to thermal oscillation on performance, organ development and intestinal morphometry from 1 to 21 days. 640-male broiler chicks were distributed in a 2x2 factorial completely randomized design (with or without dietary supplementation and at comfort temperature or thermal oscillation). Chicks subjected to thermal oscillation presented worse performance (p 0.05) than those under thermal comfort of 1 to 7, 1 to 14 and 1 to 21 days. Nutritional supplementation did not alter the performance (p 0.05) of the birds, but resulted in a higher body weight (p 0.05) regardless of the environmental thermal condition. At 7 days, chicks under thermal comfort had better intestinal morphometric parameters (p 0.05), in relation to birds under thermal oscillation. In conclusion, the temperature oscillations caused negative consequences to the productive performance and the intestinal morphology of chicks for which dietary supplementation was not enough to mitigate the effects of the environmental challenge during the first week of life of the birds.

O objetivo do trabalho foi avaliar a eficácia de uma formulação nutricional à base de aminoácidos e vitaminas suplementadas na água de bebida de pintainhos na primeira semana de vida, submetidos à oscilação térmica sobre o desempenho produtivo, desenvolvimento de órgãos e morfometria intestinal de um a 21 dias. Foram utilizados 640 pintos de corte machos, distribuídos em um delineamento inteiramente casualizado em esquema fatorial 2x2 (com suplementação nutritiva oral ou não e em temperatura de conforto ou oscilação térmica). As aves submetidas à oscilação térmica apresentaram pior desempenho (p < 0,05) em relação às aves do grupo conforto térmico de um a sete, um a 14 e um a 21 dias. A suplementação nutritiva não alterou o desempenho (p < 0,05) das aves, mas resultou em maior peso dos órgãos (p < 0,05) independentemente da condição térmica ambiental. Aos sete dias, as aves em conforto térmico apresentaram melhores parâmetros morfométricos intestinais (p < 0,05), em relação às aves submetidas à oscilação térmica. Em conclusão, as oscilações de temperatura ocasionaram consequências negativas ao desempenho produtivo e à morfologia intestinal das aves na qual a suplementação nutritiva não foi suficiente para amenizar os efeitos do desafio ambiental na primeira semana de vida das aves.

Assuntos

RESUMO

The aim of the study was to evaluate the efficacy of a nutritional formulation based on amino acids and vitamins supplemented in the drinking water for chicks in the first week of life subjected to thermal oscillation on performance, organ development and intestinal morphometry from 1 to 21 days. 640-male broiler chicks were distributed in a 2x2 factorial completely randomized design (with or without dietary supplementation and at comfort temperature or thermal oscillation). Chicks subjected to thermal oscillation presented worse performance (p 0.05) than those under thermal comfort of 1 to 7, 1 to 14 and 1 to 21 days. Nutritional supplementation did not alter the performance (p 0.05) of the birds, but resulted in a higher body weight (p 0.05) regardless of the environmental thermal condition. At 7 days, chicks under thermal comfort had better intestinal morphometric parameters (p 0.05), in relation to birds under thermal oscillation. In conclusion, the temperature oscillations caused negative consequences to the productive performance and the intestinal morphology of chicks for which dietary supplementation was not enough to mitigate the effects of the environmental challenge during the first week of life of the birds.(AU)

O objetivo do trabalho foi avaliar a eficácia de uma formulação nutricional à base de aminoácidos e vitaminas suplementadas na água de bebida de pintainhos na primeira semana de vida, submetidos à oscilação térmica sobre o desempenho produtivo, desenvolvimento de órgãos e morfometria intestinal de um a 21 dias. Foram utilizados 640 pintos de corte machos, distribuídos em um delineamento inteiramente casualizado em esquema fatorial 2x2 (com suplementação nutritiva oral ou não e em temperatura de conforto ou oscilação térmica). As aves submetidas à oscilação térmica apresentaram pior desempenho (p < 0,05) em relação às aves do grupo conforto térmico de um a sete, um a 14 e um a 21 dias. A suplementação nutritiva não alterou o desempenho (p < 0,05) das aves, mas resultou em maior peso dos órgãos (p < 0,05) independentemente da condição térmica ambiental. Aos sete dias, as aves em conforto térmico apresentaram melhores parâmetros morfométricos intestinais (p < 0,05), em relação às aves submetidas à oscilação térmica. Em conclusão, as oscilações de temperatura ocasionaram consequências negativas ao desempenho produtivo e à morfologia intestinal das aves na qual a suplementação nutritiva não foi suficiente para amenizar os efeitos do desafio ambiental na primeira semana de vida das aves.(AU)

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