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1.
Materials (Basel) ; 17(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38998352

RESUMO

Escalating global surface temperatures are highlighting the urgent need for energy-saving solutions. Phase-change materials (PCMs) have emerged as a promising avenue for enhancing thermal comfort in the construction sector. This study assessed the impact of incorporating PCMs ranging from 1% to 10% by mass into composite Portland cement partially replaced by fly ash (FA) and nanosilica particles (NS). Mechanical and electrochemical techniques were utilized to evaluate composite cements. The results indicate that the presence of PCMs delayed cement hydration, acting as a filler without chemically interacting within the composite. The combination of FA and PCMs reduced compressive strength at early ages, while thermal conductivity decreased after 90 days due to the melting point and the latent heat of PCMs. Samples with FA and NS showed a significant reduction in the CO2 penetration, attributed to their pozzolanic and microfiller effects, as well as reduced water absorption due to the non-absorptive nature of PCMs. Nitrogen physisorption confirmed structural changes in the cement matrix. Additionally, electrical resistivity and thermal behavior assessments revealed that PCM-containing samples could reduce temperatures by an average of 4 °C. This suggested that PCMs could be a viable alternative for materials with thermal insulation capacity, thereby contributing to energy efficiency in the construction sector.

2.
Ergonomics ; : 1-24, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38318846

RESUMO

Personal Comfort Systems (PCS) are equipments that heat and/or cool occupants without affecting surrounding environments, ranging from commonly used devices to innovative technologies, and that tend to be controlled by people. These systems aim to address energy consumption and occupant satisfaction issues related to centralised air-conditioning. Although there are systematic studies on these systems, there is a lack of documentation regarding mediation characteristics between people and the built environment. This article presents a systematic review of PCS using a search of academic literature and patents, classifying PCS based on thermal categories and device typologies while introducing post-phenomenological mediation categories. The results show that most PCS fall into the thermal categories of 'Heating' and 'Cooling and ventilation'. The review also presents a view of the PCS territory based on mediation attributes and technological complexity. Finally, the PCS' characteristics are discussed based on the post-phenomenological concepts of Embodiment, Hermeneutic, and Background providing insights for future research opportunities and PCS development.


Practitioner summary: This study presents a systematic review of Personal Comfort Systems (PCS) found in patents and academic databases, integrating post-phenomenological concepts into PCS discussion. It visualises the PCS territory using a matrix based on mediation relations and technological complexity, providing insights into PCS development and research opportunities.

3.
Int J Biometeorol ; 68(4): 675-690, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38180571

RESUMO

This study aims to evaluate agreement among subjective thermal comfort, thermal sensation, thermal perception, and thermal tolerance indices, according to pedestrians in downtown Santa Maria, southern Brazil, which has a humid subtropical climate (Cfa). Between August 2015 and July 2016 (three periods), 1728 questionnaires were applied. Evaluation of the dependence of statistical variables was based on gender and age, at three periods of time: August 2015 (864 respondents), January 2016 (432 respondents), and July 2016 (432 respondents). Statistical evaluation was based on Pearson's chi-square test using RStudio software, and a significance level (α) of 5% for thermal comfort, thermal sensation, thermal preference, and thermal tolerance was used. Results indicated that age and gender affect the relationship between the variables. Thermal comfort and thermal tolerance presented the best correlation and coherence, regardless of age or gender. This study contributes to knowledge on the local microclimate and can contribute to urban planning to implement strategies that improve pedestrians' thermal comfort.


Assuntos
Pedestres , Humanos , Clima , Microclima , Sensação Térmica , Percepção , Cidades
4.
Trop Anim Health Prod ; 56(2): 54, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261022

RESUMO

This study evaluated litter performance, behavioral and physiological parameters, and milk characteristics of sows submitted to different thermal environments. Fifty sows were distributed in a completely randomized design with two treatments: an evaporative cooling system (ECS) and a conventional system (CS). Sow and its litter were characterized as an experimental unit. The animals were weighed at equalization and weaning. Feed intake, milk production, and bromatological characteristics of milk were measured; the sows respiratory rate, rectal, and surface temperature were monitored. Litter uniformity was determined at equalization and weaning. Behaviors of the sows and litters were monitored for 24 h on the 7th and 15th day of lactation. Temperature and relative humidity inside the maternity was 25.00 to 28.00 °C and 26.00 to 32.55 °C and 30.00 to 70.00% and 70.00 to 88.00%, respectively, considering ECS and CS. Nutritional quality of the milk remained stable during lactation in both systems evaluated. ECS improved the average weight of the piglets, weaning weight, and daily milk production by 0.038, 0.699, and 2.31 kg/day, respectively. Sows housed in the ECS had a reduction in physiological parameters and, increase in inactive alert behavior (1.79 percentage points) and breastfeeding behavior. Piglets showed a decrease of 2.43% in the range of feedings at night and 0.15% during the day. ECS provided better comfort to the sows at the expense of the CS and, consequently, better litter performance.


Assuntos
Lactação , Clima Tropical , Animais , Feminino , Ingestão de Alimentos , Leite , Suínos , Desmame
5.
Int J Biometeorol ; 68(2): 229-236, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012375

RESUMO

This study aimed to evaluate and compare the physiological performance of different genetic groups of sheep, by physiological variables and serum hormone levels, in a hot weather environment. Thirty sheep from five genetic groups were used: Santa Inês (SI), ½ Dorper + ½ Santa Inês (DO), ½ Ilê de France + ½ Santa Inês (IF), ½ Suffolk + ½ Santa Inês (SK), and ½ Texel + ½ Santa Inês (TX). The readings and records of physiological parameters (respiratory rate (RR), rectal temperature (RT), auricular cavity temperature (ACT), and surface temperature (ST)) were carried out at 7:00 am, 1:00 pm, and 7:00 pm, in 12 non-consecutive days. The collections of blood samples for hormone analysis (triiodothyronine (T3), thyroxine (T4), and cortisol (CORT)) is in four consecutive days. The environmental conditions of the experimental period caused a thermal discomfort in the sheep, but not a state of thermal stress. The thermolysis mechanisms, sensitive (ST and ACT) and latent (RR) processes, were enough to maintain their homeostasis (RT). The results showed that crossbred breeds presented a higher metabolism and were more efficient at dissipating heat through thermolysis than the SI breed. The crossbred breeds were efficient at dissipating heat through the elevation of body surface temperature and respiratory rate, mainly SK and TX, i.e., crossbred breeds, despite the wool cover, used thermoregulatory mechanisms that promoted lower variation of RT. The analysis of variance showed significant effects (P < 0.05) to the time factor in the responses of T4 and T3, and to the breed factor in the responses of CORT, T4, and T3. We did not observe interaction between the factors to any of the hormonal variables. Therefore, we can state that the effect of time was independent of breed and vice versa. Thyroid hormones presented lower blood concentration in the mornings (4.03 ± 0.82, T4; 65.08 ± 10.6, T3), increasing their concentration in the afternoon (4.60 ± 1.03, T4; 70.16 ± 14.17, T3). The thyroid hormones presented a normal circadian rhythm, with the exception of SK. Air temperature (AT) showed greater correlation with physiological variables than enthalpy (H) did, in the experimental conditions. However, H showed correlation with T4 and T3. The adaptive profile of the genetic groups under study are different, but the IF genetic group showed better performance under environmental conditions.


Assuntos
Regulação da Temperatura Corporal , , Ovinos/genética , Animais , Temperatura Corporal , Hormônios Tireóideos , Tri-Iodotironina
6.
Trop Anim Health Prod ; 55(6): 354, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816922

RESUMO

Two experiments were carried out to evaluate the effect of monensin in supplements for grazing heifers. In experiment I, treatments consisted of protein supplements (low intake - 0.5 kg/animal/day and high intake - 1.0 kg/animal/day) associated or not with monensin. Animal performance, nutrient intake, and digestibility were evaluated. Forty crossbred heifers with an initial body weight (BW) of 213.8 ± 4.5 kg were used. There was no difference in average daily gain between treatments (average of 0.588 kg/animal/day). There was no interaction between monensin and supplements for intake parameters and digestibility. Dry matter (DM) intake was equal between treatments (~ 2% of BW). However, there was a reduction in pasture intake with the high-intake supplement. In experiment II, treatments consisted of two types of supplements (protein or mineral) associated or not with monensin. The variables analyzed were productive performance, ingestive behavior, and thermal comfort, evaluated through the index of thermal stress for cows (ITSC). Forty crossbred heifers with a BW of 159.2 ± 1.3 kg were used. The type of supplement did not influence the performance of the animals. However, monensin promoted greater weight gain in the animals (110 g/animal/day). There was an interaction effect between supplementation and monensin addition on behavioral activities, except for idle time. The inclusion of monensin in the protein supplement reduced the grazing time. The ITSC value influenced the activities of ingestive behavior, and the increase of this index reduced the grazing time in all treatments. Forage quality influences the response to monensin use, and the addition of monensin in supplements for grazing cattle during the rainy season is recommended for forages with high CP content.


Assuntos
Suplementos Nutricionais , Monensin , Bovinos , Animais , Feminino , Estações do Ano , Suplementos Nutricionais/análise , Ingestão de Energia , Minerais , Ração Animal/análise , Digestão , Dieta/veterinária
7.
Front Vet Sci ; 10: 1198678, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520006

RESUMO

The good productive and reproductive performance of the animals depends on multiple factors, including favorable climatic conditions, which are responsible for causing changes in the physiological and behavioral responses. Thus, the objective of this study was to evaluate the temperature and humidity index (THI) to support the implementation of a rearing system in ruminants in the Western Amazon, Brazil. Monthly temperature and relative humidity data were obtained from the Database for Teaching and Research (BDMEP) for the capitals Manaus (Amazonas), Boa Vista (Roraima), and Rio Branco (Acre), considering a historical series of 27 years (1993 to 2020), referring from January to December. In the capital Boa Vista, the months of January, February, May, June, and July showed an indication of mild stress and the months of March, April, August, September, October, November, and December had moderate stress. In Rio Branco, all months of the year presented the average THI in mild stress with variations of lower THI (73) and higher THI (77). In the capital Manaus, the months from January to July signaled mild stress, but from August to November, there was moderate stress, and in December, there was mild stress. It is possible to observe significant climatic variations during the months as well as the years of study, with the animals under thermal stress with THI > 72 or in a warning signal, with a gradual increase in temperature and humidity indices over the last 10 years. The importance of the breeding system and the consideration of environmental factors, such as the THI, are fundamental for the wellbeing and performance of cattle raised in the field. Our results support the adoption of heat stress mitigation strategies for ruminants in Western Amazon.

8.
Trop Anim Health Prod ; 55(3): 158, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37052750

RESUMO

Heat stress is one of the most important environmental challenges faced by dairy cattle, with a deleterious effect on animal production and welfare. This research was conducted to evaluate the effects of the thermal environment on the physiological and behavioral responses of dairy cattle in a rotational picket. The research was conducted on an experimental farm, located in the Agreste region of the state of Pernambuco, Brazil. The animals were managed in a rotational picket system of signal grass, with an occupation and a rest period of 7 and 28 days, respectively, for a stocking rate of 3.2 AU ha-1. The determination of the effect of stressors on the animals was performed by recording the dry bulb temperature (°C), and the relative humidity, which allowed the characterization of the thermal environment by the temperature and humidity index and by the specific enthalpy (kJ kg-1). The physiological variables monitored were respiratory rate (mov. min-1), rectal temperature (°C), and skin temperature (°C). The behavioral responses quantified were activities, walking, ruminating, idling and ingestive behaviors, eating, and drinking, with the percentage of time spent on each activity being recorded. According to the canonical multivariate analysis, the chi-square test, and the variation of physiological patterns, the animals, even in a situation of greater thermal challenge, presented physiological responses within conditions considered normal; however, they reduced grazing activity (eating) during the hottest hours and increased the activities of rumination and idling.


Assuntos
Adaptação Fisiológica , Temperatura Alta , Animais , Bovinos , Feminino , Temperatura Corporal , Comportamento Alimentar , Umidade , Lactação/fisiologia , Temperatura , Métodos de Alimentação , Comportamento Animal
9.
Animals (Basel) ; 13(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36978664

RESUMO

The Intergovernmental Panel on Climate Change (IPCC) has pointed out the high vulnerability of developing countries to climate change, which is expected to impact food and income security. Sheep farming is one of the main animal productions among the families located in the most vulnerable regions of the semiarid region of Pernambuco state, a Brazilian territory known for its high temperatures, low relative humidity, and high net solar radiation. Therefore, the objective of this study was to identify different regions of Pernambuco that may be more suitable for different breeds of sheep, based on non-parametric statistics and kriging maps of the temperature and humidity index (THI). THI values were determined based on mean annual temperature and wind speed extracted from the TerraClimate remote sensing database. Pernambuco state presented THI values ranging from 66 to 79, with the hair breeds having a high potential for exploitation in almost all territories, including the main meat-producing breeds. The East Friesian breed, a high milk producer, would be well suited to the Agreste mesoregion, a territory that, like the Pajeú and Moxotó microregions, also proved favorable for the introduction of three wool breeds (Suffolk, Poll Dorset, and Texel) known as major meat producers. The kriging maps of the THI values successfully allowed the identification of strategic development regions of Pernambuco state with high potential for sheep breeding.

10.
Animals (Basel) ; 13(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36766218

RESUMO

Animal Agrivoltaics combines electric energy generation, animal thermal comfort, and sustainable production at the same time. This model of production can foster the sustainable intensification of dairy production in tropical areas where solar irradiance is high and nearly constant throughout the year. In this study, we propose Animal Agrivoltaics as an alternative practice to reduce the heat load and eCH4 emissions from dairy heifers in tropical areas. To attest this hypothesis, (1) the meteorological data and the behavioral and physiological responses of the animals were integrated in order to determine the benefits provided by the shade from the solar panels on the thermoregulation of the dairy heifers, and (2) measurements of the enteric methane emissions were taken to determine the potential of the solar panels to offset the GHG. Seven crossbred Holstein heifers (7/8, Holstein × Gyr) with a mean body weight of 242 kg (SD = 53.5) were evaluated in a paddock shaded with ten modules of solar panels. Miniature temperature loggers were used to record the body surface, skin and vaginal temperatures of the heifers every five minutes. The respiratory rate and the shade-use behavior were also monitored by two observers. These measurements were taken from 08:00 to 17:00 h for 18 consecutive days. After completing the field study, the heifers underwent for assessments of the daily oscillations of eCH4 emission using a flow-through respirometry system. The use of shade by the heifers was progressively increased (p < 0.01) with an increasing level of solar irradiance. Lying and ruminating were more likely (p < 0.01) to occur when the heifers were in the shade, especially when the solar irradiance exceeded 500 W m-2. Between 10:00 and 14:00 h, the heifers benefited from the shade produced by the solar panels, with a reduction of 40% in the radiant heat load. With an increasing intensity of solar irradiance, body surface temperature, skin temperature and respiratory rate of the heifers in the shade were lower (p < 0.01) compared to when they were exposed to the sun. The heifers had a daily methane emission total of 63.5 g per animal-1 or 1.7 kg of CO2-eq. Based on this emission rate and the amount of CO2-eq that was not emitted to the atmosphere due to the electricity generated by solar panels, 4.1 m2 of panels per animal (nominal power = 335 W) would be expected to obtain a net-zero eCH4 emission. Over a period of one year (from September 2018 to August 2019), a set of ten photovoltaic panels used in the study produced 4869.4 kWh of electricity, thereby saving US $970.00 or US $48.00 per m2 of solar panel. Based on the results of this study, it can be concluded that use of Animal Agrivoltaics, in addition to producing electricity, has significant potential benefit in providing better thermal comfort to cattle, as well as offsetting the enteric methane emissions released into the environment. In addition, the system would provide extra income to farmers, as well as a potential source of energy micro-generation.

11.
Sci Total Environ ; 856(Pt 1): 158978, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162585

RESUMO

The residential sector is one of the primary energy consumers and emitters of greenhouse gases. Given the environmental problem, one of the methods of mitigating electricity consumption and reducing the temperature in buildings is green infrastructure: green roofs and walls. This article presents a compilation of the studies carried out in México about green infrastructure; the energy, thermal and environmental benefits obtained were analyzed according to the vegetation, substrate, climate, and systems configuration. In addition, the development of policies, laws, regulations, and incentives in the field of green roofs in Mexico was also analyzed. The results indicate that using green infrastructure can help mitigate greenhouse gases since a green roof can reduce the indoor temperature up to 19.9 °C, save 28 % annually in electricity consumption and remove 80 % of rainwater pollutants. Finally, the results of this research can provide insight for researchers, legislators, and urban planners about the state in which Mexico is located, as well as help in decision-making.


Assuntos
Conservação dos Recursos Naturais , Gases de Efeito Estufa , Conservação dos Recursos Naturais/métodos , México , Clima , Pesquisa
12.
Work ; 74(3): 955-966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36404563

RESUMO

BACKGROUND: The scientific literature has already identified the influence of thermal conditions on health and performance of students. However, users' opinions are often overwhelmed by normative evaluations, not receiving the necessary attention. OBJECTIVE: To quantitatively compare the influence of air temperature variability on the thermal perception of students from six air-conditioned teaching environments located in four regions of Brazil. METHODS: Three-day experiments were carried out in six environments. A thermal condition was proposed for each day. From that, the environmental parameters were measured and a questionnaire about the thermal perception was applied. Then, Generalized Linear Models were applied to obtain a measure of effect and hypothesis test and confidence interval were used to find comfort zones and compare environments. RESULTS: The results showed that students from environments A, B, C and E felt less the effects of the increase in air temperature compared to students from environments D and F. In addition, students from environments A, B, C and E showed less perceptual variability compared to students from environments D and F. CONCLUSIONS: Students acclimated to higher thermal conditions felt less the effects of the increase in air temperature, showed less perceptual variability and a higher degree of thermal adaptability.


Assuntos
Percepção , Estudantes , Humanos , Temperatura , Brasil , Universidades
13.
Int J Biometeorol ; 67(2): 405-408, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36316403

RESUMO

This brief background highlights Brazil as a 'climate-health hotspot', i.e. a country where climate affects local populations negatively through multiple pathways (Di Napoli et al. BMC Public Health 22(1):1-8, 2022). Knowledge gaps still need to be filled concerning the various climaterelated dimensions of tourism, vector-borne diseases, mortality and morbidity in urban centers in the country (Krüger et al. Int J Biometeorol 66(7):1297-1315, 2022). Motivated by this, the first Brazilian Symposium on Human Biometeorology (Simpósio Brasileiro de Biometeorologia Humana 2022) was organized and held at the Federal University of Rio Grande do Norte (UFRN) in Natal, northeastern Brazil, between July 4 and 8, 2022. The symposium was organized as a hybrid event by a committee composed of researchers acting in different regions of the country, and who had an ongoing research collaboration on matters related to human biometeorology. The event was partly sponsored by the ISB and partly self-supported by the organizers and institutions involved. The symposium aimed to promote the development of the research area on human biometeorology in Brazil in facing challenges imposed by a globally and locally changing climate. To achieve this, the symposium focused on five main topics of discussion: a) climate-driven diseases; b) thermal comfort, urban and architectural biometeorology; c) atmospheric pollution and health; d) climate change; e) climate, health and climate change. This summary highlights the main findings, future research directions, and policy implications in each topic from the presentations and panel discussions.


Assuntos
Mudança Climática , Meteorologia , Humanos , Brasil , Morbidade
14.
Artigo em Inglês | MEDLINE | ID: mdl-36231507

RESUMO

There is a need to ensure comfortable conditions for hospital staff and patients from the point of view of thermal comfort and air quality so that they do not affect their performance. We consider the need for hospital employees and patients to enjoy conditions of greater well-being during their stay. This is understood as a comfortable thermal sensation and adequate air quality, depending on the task they are performing. The contribution of this article is the formulation of the fundamentals of a system and platform for monitoring thermal comfort and Indoor Air Quality (IAQ) in hospitals, based on an Internet of Things platform composed of a low-cost sensor node network that is capable of measuring critical variables such as humidity, temperature, and Carbon Dioxide (CO2). As part of the platform, a multidimensional data model with an On-Line Analytical Processing (OLAP) approach is presented that offers query flexibility, data volume reduction, as well as a significant reduction in query response times. The experimental results confirm the suitability of the platform's data model, which facilitates operational and strategic decision making in complex hospitals.


Assuntos
Poluição do Ar em Ambientes Fechados , Internet das Coisas , Poluição do Ar em Ambientes Fechados/análise , Dióxido de Carbono/análise , Monitoramento Ambiental/métodos , Hospitais , Humanos , Energia Renovável , Temperatura
15.
Trop Anim Health Prod ; 54(6): 353, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36264392

RESUMO

This study was conducted to evaluate the effects of slaughtering feedlot Texel lambs during different climatic conditions on carcass and meat quality traits. Twenty castrated male Texel lambs (21.8 ± 0.62 kg) were distributed to two treatments according to the climatic conditions during the finishing period and at pre-slaughter: warm season (WS; mean temperature of 23.4 °C and 77.5% relative humidity) and cool season (CS; mean temperature of 14.9 °C and 79.5% relative humidity). During the pre-slaughter, thermal comfort was evaluated through the variables: respiratory frequency, rectal temperature, temperature of the ocular region, and temperature-humidity index (THI). After the finishing period, lambs were slaughtered, and carcass and meat quality traits were assessed. The THI values indicate that animals harvested in the WS spent 13 h of the day under potential thermal discomfort conditions in the week before slaughter and in the pre-slaughter period, whereas lambs harvested in the CS did not experience any thermal discomfort. Slaughter weight, carcass weight, carcass dressing, and backfat thickness were greater (P ≤ 0.03), whereas cooling losses were lower (P < 0.01) for lambs slaughtered in the CS. Moreover, thawing losses were lower (P < 0.01), whereas cooking losses were greater (P < 0.01) for lambs harvested in the CS. Lambs slaughtered in the CS also showed greater meat redness, yellowness, and chroma values (P < 0.05). Although carcass traits were affected by the greater thermal discomfort exposure, meat quality of lambs was less impacted by the climatic conditions at slaughter.


Assuntos
Composição Corporal , Carne Vermelha , Ovinos , Masculino , Animais , Estações do Ano , Carne , Carneiro Doméstico
16.
Int J Biometeorol ; 66(12): 2417-2424, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36264504

RESUMO

We studied the effects of heat waves (HW), defined as three consecutive days with an ambient temperature ≥ 25 °C and a temperature and humidity index (THI) > 74, on the reproductive performance of sows. Meteorological data were obtained from the National Institute of Meteorology and reproductive data from a commercial farm with 51,578 inseminations and 49,103 pregnancies from September 5, 2013, to July 12, 2019. Sows were divided into the following groups according to the parity order: group 1 (sows that did not experience HW on the day of insemination) and group 2 (sows exposed to HW on the day of insemination). The percentage of days that pregnant sows were exposed to HW was calculated as 0 to 25% (1), 26 to 50% (2), 51 to 75% (3), and > 75% (4). Out of a total of 2137 days, there were 160 HW and more than 10 HW per month, except in May, June, and July. Gilts in group 2 showed a decrease in the percentage of gestation (98.21% and 98.78%, respectively, P = 0.0267) and the percentage of births compared with those in group 1 (95.53% and 96.61, respectively, P = 0.0065). Primiparous sows in group 2 had a higher percentage of abortions than gilts in group 1 (3.20% and 2.42%, respectively; P = 0.0334). Sows exposed to more than 50% HW during gestation produced more mummified piglets than sows exposed to less than 50% HW. The number of stillborn piglets was higher in sows exposed to temperatures above 25% HW during gestation. The occurrence of heat waves in gilts and primiparous sows impairs reproductive performance.


Assuntos
Temperatura Alta , Reprodução , Gravidez , Humanos , Suínos , Animais , Feminino , Paridade , Parto , Natimorto
17.
Int J Biometeorol ; 66(11): 2301-2308, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36053296

RESUMO

This work aims to analyze the relationship between meteorological conditions and the occurrence of hospital admissions for pneumonia in children under 5 years of age in the Metropolitan Region of Porto Alegre, Brazil, from 1998 to 2017. To this end, data from hospital admissions obtained from the Unified Health System database (DATASUS) were used and classified into two groups: acute respiratory infections (ARI) and asthma, according to the international classification of diseases, tenth edition (ICD-10). Data regarding meteorological variables were also used: temperature, relative humidity, atmospheric pressure and wind speed, at 12Z and 18Z, as well as the Thermal Comfort Index (TCI), Effective Temperature as a function of the wind (ETw) and Windchill (W). From the data obtained, a descriptive analysis of the diseases and a statistical analysis with the analysis of correlation and main components were performed. Results showed that pneumonia (catalogued in the ICD-10 as J12 to J18) was the main cause of hospitalizations in children. The annual, monthly and daily hospitalization frequency distributions showed higher rates of admissions occurring in the months of May to September. The peaks of admissions and high admissions (HA) occurred mainly in the winter months (June, July and August), and in 1998. Meanwhile, the correlation and principal component analysis showed an increase in hospital admissions due to pneumonia related to a decrease in temperature and ETw and W indices (negative anomalies) and an increase in atmospheric pressure and relative humidity (positive anomalies).


Assuntos
Asma , Pneumonia , Criança , Humanos , Pré-Escolar , Brasil/epidemiologia , Pneumonia/epidemiologia , Estações do Ano , Hospitalização , Asma/epidemiologia
18.
Theor Appl Climatol ; 149(3-4): 1645-1658, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36061347

RESUMO

Outdoor thermal comfort (OTC) surveys require synchronous monitoring of meteorological variables for direct comparisons against subjective thermal perception. The Universal Thermal Climate Index (UTCI) is a feasible index as it integrates meteorological conditions as a single value irrespective of urban morphological attributes or biological sex, age and body mass. ERA5-HEAT (Human thErmAl comforT) is a downloadable reanalysis dataset providing hourly grids of UTCI climate records at 0.25° × 0.25° spatial resolution from 1979 to present. We here evaluate for the first time whether it is possible to use ERA5-HEAT data as a proxy for the UTCI measured onsite during OTC surveys. A dataset comprising 1640 survey responses gathered over 14 OTC campaigns in Curitiba, Brazil (25°26'S, 49°16'W) was analysed. We assessed the bias obtained between the Dynamic Thermal Sensation, an index derived from the UTCI, and the thermal sensation reported by survey participants by considering locally measured meteorological variables and ERA5-HEAT reanalysis data. As ERA5-HEAT data are given on an hourly basis, prediction bias can be greatly reduced when accounting for survey responses close to the hour. In terms of seasons, the fall and winter seasons have diminished mean bias, though with larger spread than in summer. In terms of UTCI stress categories, prediction bias is lower for the thermal comfort range. When comparing reanalysis data against WMO station data as proxy candidates for survey field data, the former presented lower bias, less spread in terms of standard deviation and higher correlation to in situ data.

19.
Animals (Basel) ; 12(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36009645

RESUMO

The objective of this study was to evaluate and characterize the dependence and the spatial and temporal distribution of variables and indices of the thermal environment in an open compost-bedded pack barn system with positive-pressure ventilation (CBPPV) during the winter period. The study was conducted in a CBPPV system located in the Zona da Mata region, Minas Gerais, Brazil. The indoor environment was divided into a mesh composed of 55 equidistant points, where data on dry-bulb air temperature (tdb) and relative humidity (RH) were collected. The collected data were divided into four periods-dawn, morning, afternoon, and night-and mean values were obtained. To evaluate the thermal microenvironment, the temperature and humidity index (THI) and the specific enthalpy of air (h) were used. For spatial dependence analysis, geostatistical techniques were applied. Through the results, a strong spatial dependence was verified for all variables evaluated. Through THI and h maps, conditions of thermal comfort were found for dairy cattle. The highest values of tdb, THI, and h were recorded in the afternoon period in the northwest region of the facility (tdb = 23.2 °C, THI = 69.7, and h = 50.9 kJ∙kg of dry air-1).

20.
Animals (Basel) ; 12(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35883322

RESUMO

Evaporative cooling is one of the most efficient techniques to reduce heat stress in cows in agricultural facilities. Additionally, compost-bedded pack barn has been shown to improve the welfare and production of cows. Two techniques were combined and analysed by developing a computational fluid dynamics (CFD) model of a tunnel-ventilated compost-bedded packed barn that integrated the heat and airflow dynamics of an evaporative pad cooling system. This allowed us to study the distribution of dry-bulb temperature, relative humidity and airflow velocity inside the barn based on the external environmental conditions, thickness of the pad, water temperature and specific manufacturer characteristics of the pad, providing optimal cooling pad location, size and operating conditions in the barn. Employing experimental data the CFD model was validated showing good agreement. The Equivalent Temperature Index for dairy Cattle (ETIC) was used to determine the level of stress of the cows considering the airflow velocity. It was found a moderate stress due to high relative humidity and low airflow velocity. From the predicted results, it was recommended to increase the airflow velocity above 3 m s-1 when simultaneously the external dry-bulb temperature and relative humidity exceed 30 °C and 55%, respectively, simultaneously. Additionally, installation of baffles at the pad outlet to drive the airflow to the floor was suggested to improve the drying of the compost-bedded closed to the pads, where a low airflow velocity region was established.

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