Αρχειοθήκη ιστολογίου

Κυριακή 9 Δεκεμβρίου 2018

Biometeorology

The significant role of health surveillance in the occupational heat stress assessment

Abstract

In order to address the heat stress hazard, the worker health surveillance makes a difference by providing information about individual factor, feedback, and evidence about efficacy of preventive measures and activities carried out through the risk assessment process, at individual and group levels. Every technical, procedural, or organizational measures could be ineffective without taking into account the results provided by health surveillance.

Coupling of urban energy balance model with 3-D radiation model to derive human thermal (dis)comfort

Abstract

While capabilities in urban climate modeling have substantially increased in recent decades, the interdependency of changes in environmental surface properties and human (dis)comfort have only recently received attention. The open-source solar long-wave environmental irradiance geometry (SOLWEIG) model is one of the state-of-the-art models frequently used for urban (micro-)climatic studies. Here, we present updated calculation schemes for SOLWEIG allowing the improved prediction of surface temperatures (wall and ground). We illustrate that parameterizations based on measurements of global radiation on a south-facing vertical plane obtain better results compared to those based on solar elevation. Due to the limited number of ground surface temperature parameterizations in SOLWEIG, we implement the two-layer force-restore method for calculating ground temperature for various soil conditions. To characterize changes in urban canyon air temperature (Tcan), we couple the calculation method as used in the Town Energy Balance (TEB) model. Comparison of model results and observations (obtained during field campaigns) indicates a good agreement between modeled and measured Tcan, with an explained variance of R2 = 0.99. Finally, we implement an energy balance model for vertically mounted PV modules to contrast different urban surface properties. Specifically, we consider (i) an environment comprising dark asphalt and a glass facade and (ii) an environment comprising bright concrete and a PV facade. The model results show a substantially decreased Tcan (by up to − 1.65°C) for the latter case, indicating the potential of partially reducing/mitigating urban heat island effects.

Temperature sensitivity of willow dwarf shrub growth from two distinct High Arctic sites

Abstract

The High Arctic region has experienced marked climate fluctuations within the past decades strongly affecting tundra shrub growth. However, the spatial variability in dwarf shrub growth responses in this remote region remains largely unknown. This study characterizes temperature sensitivity of radial growth of two willow dwarf shrub species from two distinct High Arctic sites. The dwarf shrub Salix arctica from Northern Greenland (82°N), which has a dry continental High Arctic climate, is linked with Salix polaris from central Svalbard (78° N), which experiences a more oceanic High Arctic climate with relatively mild winters. We found similar positive and significant relationships between annual growth of both Salix dwarf shrub species and July–August air temperatures (1960–2010), despite different temperature regimes and shrub growth rates at the two sites. Also, Salixdwarf shrub growth was significantly negatively correlated with Arctic and North Atlantic Oscillation (AO/NAO) indices; S. arctica from Northern Greenland was negatively correlated with previous autumn (AO index) and current summer AO and NAO indices, and S. polaris with the summer NAO index. The results highlight the importance of both local and regional climatic drivers for dwarf willow shrub growth in harsh polar desert habitats and are a step in the direction of identifying and scaling changes in plant growth across the High Arctic.

Analysis of meteorological dryness/wetness features for spring wheat production in the Ili River basin, China

Abstract

Understanding the impacts of climate change on crop yield is important for improving crop growth and yield formation in northwestern China. In this study, we evaluated the relationship between meteorological dryness/wetness conditions and spring wheat yield in the Ili river basin (IRB). The climate and yield data from 1961 to 2013 were collected to analyze characteristics and correlations between these two variables using the standardized precipitation evapotranspiration index (SPEI), yield detrending method, modified Mann-Kendall test and Spearman correlation analysis. Main results were as follows: (1) correlations between monthly SPEI values (MSV) and climatic yield of spring wheat indicated that the dryness/wetness condition in May was a key factor affecting yield in the whole region; (2) although the MSV in May and yield fluctuated from negative to positive values in time, the severely and extremely dryness events were in good agreement with the higher yield losses; (3) each increase of 0.5 MSV in May promoted over 3% increase of yield in most part of IRB; however, the larger variability of MSV in May resulted in larger yield fluctuations; and (4) the Tibetan Plateau index in April showed significant correlations with the MSV in May and yield, which provided a precursory signal for decision-makers to better understand potential yield fluctuations.

Associations between ambient temperature and daily hospital admissions for rheumatic heart disease in Shanghai, China

Abstract

Rheumatic heart disease (RHD) remains a serious public health burden in developing countries. We conducted a time-series study to explore the association between ambient temperature and daily hospital admissions for RHD in Shanghai, China. We collected data on daily hospital admissions for RHD from 2013 to 2015 from the database of Shanghai Health Insurance System. We applied the generalized additive models together with the distributed lag nonlinear model to estimate the association between temperature and RHD hospital admissions after controlling for relative humidity, time trend, day of the week, and holidays. Stratification analyses by age and gender were performed to evaluate their potential effect modification. A total of 4178 cases of RHD hospitalizations were identified over the study period. There were almost linear, positive, and significant associations between daily mean temperature and RHD hospital admissions with higher risks at hotter days. Compared to reference temperature (0 °C), the cumulative risks of moderate heat (the 90th percentile of temperature, 28.0 °C) and extreme heat (the 99th percentile of temperature, 33.5 °C) over lags 0–5 days were 2.55 (95% confidence interval 1.14, 5.73) and 3.22 (95% confidence interval 1.36, 7.61), respectively. These associations were significantly stronger in older people than in younger people. This study indicated larger risks of RHD hospital admissions associated with higher temperature, especially in older people. Our findings provided first-hand epidemiological evidence regarding the effects of ambient temperature on RHD incidence.

The spatial distribution of BUN reference values of Chinese healthy adults: a cross-section study

Abstract

The blood urea nitrogen (BUN) is generally regarded as a significant serum marker in estimating renal function. This study aims to explore the geographical distribution of BUN reference values of Chinese healthy adults, and provide a scientific basis for determining BUN reference values of Chinese healthy adults of different regions according to local conditions. A total of 25,568 BUN reference values of healthy adults from 241 Chinese cities were collected in this study, and 17 geographical indices were selected as explanatory variables. The correlation analysis was used to examine the significance between BUN reference value and geographical factors, then five significant indices were extracted to build two predictive models, including principal component analysis (PCA) and support vector regression (SVR) model, then the optimal model was selected by model test to predict BUN reference values of the whole China, finally the distribution map was produced. The results show that BUN reference value of Chinese healthy adult was characteristically associated with latitude, altitude, annual mean temperature, annual mean relative humidity, and annual precipitation. The model test shows, compared with SVR model, the PCA model possesses superior simulative and predictive ability. The distribution map shows that the BUN reference values of Chinese healthy adult are lower in the east and higher in the west. These results indicate that the BUN reference value is significantly affected by geographical environment, and the BUN reference values of different regions could be seen clearly on distribution map.

Assessment of the Australian Bureau of Meteorology wet bulb globe temperature model using weather station data

Abstract

Exertional heat illnesses affect thousands of athletes each year and are a leading cause of death in sports. The wet bulb globe temperature (WBGT) is widely used as a heat stress metric in athletics for adjusting activities. The WBGT can be measured on-site with portable sensors, but instrument cost may provide a barrier for usage. Modeling WBGT from weather station data, then, presents an affordable option. Our study compares two WBGT models of varying levels of sophistication: the Australian Bureau of Meteorology (ABM) model which uses only temperature and humidity as inputs and a physically based model by Liljegren that incorporates temperature, humidity, wind speed, and solar radiation in determining WBGT outputs. The setting for the study is 19 University of Georgia Weather Network stations selected from across the state of Georgia, USA, over a 6-year period (2008–2014) during late summer and early fall months. Results show that the ABM model’s performance relative to the Liljegren model varies based on time of day and weather conditions. WBGTs from the ABM model are most similar to those from the Liljegren model during midday when the assumption of moderately high sun most frequently occurs. We observed increasingly large positive biases with the ABM model both earlier and later in the day during periods with lower solar radiation. Even during midday, large (≥ 3 °C) underestimates may occur during low wind conditions and overestimates during periods with high cloud cover. Such differences can lead to inaccurate activity modification and pose dangers for athletes either by underestimating heat-related hazards or by imposing an opportunity cost if practice activities are limited by overestimating the heat hazard.

Grain development and endogenous hormones in summer maize ( Zea mays L.) submitted to different light conditions

Abstract

Low light is a type of abiotic stress that seriously affects plant growth and production efficiency. We investigated the response mechanisms of summer maize to low light by measuring the changes in endogenous hormones in the grains and during grain filling in summer maize at different light intensities to provide a theoretical basis for the production and management of summer maize under light stress. We applied different light treatments in a field experiment as follows: S, shading from tassel stage (VT) to maturity stage (R6); CK, natural lighting in the field; and L, increasing light from VT to R6. The shading level was 60%, and the maximum illumination intensity of the increasing light treatment on cloudy days was 1600–1800 μmol m−2 s−1. Compared with the control, shading significantly increased the grain abscisic acid (ABA) content at 5–20 days after pollination and decreased the indole acetic acid (IAA), zeatin riboside (ZR), and gibberellin (GA) contents (P < 0.05). The grain-filling rate decreased under shading conditions. Meanwhile, the grain volume, grain weight, and yield all decreased; the yields in 2013 and 2014 decreased by 61 and 60%, respectively. The grain IAA, ZR, and GA contents were increased by increasing light. The grain ABA content at 5–20 days after pollination did not significantly differ from that of CK (P < 0.05). After 20 days after pollination, the ABA content decreased, the grain-filling rate and the filling duration increased, and the yield increased. However, shading after anthesis increased the grain ABA content and reduced the IAA, ZR, and GA contents. Grain growth and development were inhibited, and the yield decreased. The grain ABA content decreased; the IAA, ZR, and GA contents increased; and the yield increased after increasing light. The results indicate that different light intensities regulated the levels of grains endogenous hormones, which influenced the grain-filling rate and duration, and consequently, regulated grain weight and yield.

Balneotherapy in chronic inflammatory rheumatic diseases—a narrative review

Abstract

Since ancient time, thermal baths and mudpacks have been used as treatments for rheumatic diseases and other musculoskeletal complaints. Despite basic researches suggest an anti-inflammatory effect of spa therapy, there is no consensus about the benefits of balneotherapy in patients with chronic inflammatory rheumatic diseases. The aim of this review is to summarize the currently available information on clinical effects of balneotherapy in these diseases. We did a literature search for articles considering the randomized controlled trials (RCTs) published until today. Although many selected studies do not have an elevated methodological quality, data from these RCTs support a beneficial effect of spa therapy. Balneotherapy highly improves the clinical course of the disease in patients with predominant axial involvement, such as with ankylosing and enteropathic spondylitis; the effects are less favorable in patients with predominant peripheral articular inflammation, such as rheumatoid arthritis. Good results have been observed in patients with psoriatic arthritis, but only few RCTs have been conducted on this disease. Spa therapy appears safe, and adverse events have been reported only in a few patients.

Simple method to detect year-to-year variability of blooming phenology of Cerasus × yedoensis by digital camera

Abstract

The year-to-year variability of the blooming phenology of cherry trees is important as a proxy climate indicator and strongly affects cultural ecosystem services. Observation of blooming phenology at multiple points requires a simple and flexible approach. We examined changes in the canopy gap fraction extracted from binarized upward images taken periodically beneath a Cerasus × yedoensis ‘Somei-yoshino’ tree. The gap fraction decreased rapidly after the start of bloom, reached a minimum value at full bloom, and began to increase again, but then decreased rapidly during leaf flush. These changes reflect the phenology of blooming and leaf flush after flower drop of ‘Somei-yoshino’. These characteristics allow detection of the year-to-year variability of the bloom and leaf-flush phenology of cherry and other deciduous tree species that show the same patterns.

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Medicine by Alexandros G. Sfakianakis,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,00302841026182,00306932607174,alsfakia@gmail.com,

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