Risk assessment of drought in Yun-Gui-Guang of China jointly using the Standardized Precipitation Index and vulnerability curves

Drought is one of the most serious natural disasters in the world and causes great economic losses in China every year, especially in its southwest region. Yet, few studies have reported the quantitative comprehensive risk of drought in the Yunnan, Guizhou, and Guangxi provinces of China. Taking these three provinces as the study area, we obtained annual precipitation, disaster loss, and agricultural planting data during 1964–2013. Following an optimal estimation of annual precipitation by the Bayesian maximum entropy method, we mapped the annual Standardized Precipitation Index. Based on the theory of information diffusion and exceeding probability, the hazard of drought was evaluated. We also fit the vulnerability curves using the drought loss data. As a basis, we constructed a multiplicative formula to calculate the comprehensive risk of drought, which integrates the hazard and the vulnerability and produces drought loss rate (DLR) maps. We found that the DLR caused by mild drought was about 3%, moderate drought 10%, severe drought 25%, and extreme drought 50%. We also created a risk zoning map to provide practical information, such as a scientific basis for optimization of regional allocation of resources for drought preparedness and response

Mapping Comparison and Meteorological Correlation Analysis of the Air Quality Index in Mid-Eastern China

With the continuous progress of human production and life, air quality has become the focus of attention. In this paper, Beijing, Tianjin, Hebei, Shanxi, Shandong and Henan provinces were taken as the study area, where there are 58 air quality monitoring stations from which daily and monthly data are obtained. Firstly, the temporal characteristics of the air quality index (AQI) are explored. Then, the spatial distribution of the AQI is mapped by the inverse distance weighted (IDW) method, the ordinary kriging (OK) method and the Bayesian maximum entropy (BME) method. Additionally, cross-validation is utilized to evaluate the mapping results of these methods with two indexes: mean absolute error and root mean square interpolation error. Furthermore, the correlation analysis of meteorological factors, including precipitation anomaly percentage, precipitation, mean wind speed, average temperature, average water vapor pressure and average relative humidity, potentially affecting the AQI was carried out on both daily and monthly scales. In the study area and period, AQI shows a clear periodicity, although overall, it has a downward trend. The peak of AQI appeared in November, December and January. BME interpolation has a higher accuracy than OK. IDW has the maximum error. Overall, the AQI of winter (November), spring (February) is much worse than summer (May) and autumn (August). Additionally, the air quality has improved during the study period. The most polluted areas of air quality are concentrated in Beijing, the southern part of Tianjin, the central-southern part of Hebei, the central-northern part of Henan and the western part of Shandong. The average wind speed and average relative humidity have real correlation with AQI. The effect of meteorological factors such as wind, precipitation and humidity on AQI is putative to have temporal lag to different extents. AQI of cities with poor air quality will fluctuate greater than that of others when weather changes and has higher correlation with meteorological factors

Associations between omega-3 fatty acids and insulin resistance and body composition in women with polycystic ovary syndrome

BackgroundPolycystic ovary syndrome (PCOS) is strongly associated with abdominal obesity and insulin resistance and effective approaches to nutrition (e.g., omega-3 fatty acids intake) might improve the cardiometabolic risk profile. This study aimed to examine the associations of dietary and serum omega-3 fatty acids with insulin resistance (IR) and body composition among PCOS patients.MethodsA total of 185 patients with PCOS were included in our analysis. Dietary information was collected through face-to-face interviews using a 102-item food frequency questionnaire (FFQ). Serum omega-3 fatty acid levels were measured with the gas chromatography method. Body composition was measured by both dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance (BIA) methods. The multivariable linear regression model was applied to analyze the associations of dietary and serum omega-3 fatty acids with the levels of Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) and body composition parameters among PCOS patients.ResultsOur results indicated that the dietary long-chain omega-3 polyunsaturated fatty acids (PUFA) intakes were negatively associated with HOMA-IR (β = –0.089, P = 0.040), fat mass (β = –0.022, P = 0.047), and body fat percentage (β = –0.026, P = 0.032). For serum biomarkers, higher total omega-3 PUFAs levels (β = –0.158, P = 0.021) and long-chain omega-3 PUFAs levels (β = –0.187, P < 0.001), particularly eicosapentaenoic acid (EPA) (β = –164, P = 0.011) and docosahexaenoic acid (DHA) (β = –0.158, P = 0.001) were also associated with decreased HOMA-IR. In addition, generally, dietary and serum long-chain omega-3 PUFA levels, DPA, and DHA levels were both positively associated with muscle mass measured by DXA; whereas serum total, long-chain and individual omega-3 PUFA levels (e.g., DPA, EPA, and DHA) were all negatively associated with fat mass and body fat percentage. These findings were further confirmed by the findings for body composition measured by the BIA method.ConclusionHigher levels of dietary and serum omega-3 PUFAs, particularly long-chain omega PUFAs (DPA and DHA), might have beneficial effects on metabolic parameters and body composition among PCOS patients

Reconfigurable ultra-sparse ventilated metamaterial absorber

The impetus for examining ventilated acoustic metamaterials stems from the demand for increasingly efficient and adaptable noise reduction and sound wave manipulation techniques. However, for the present reconfigurable metamaterial absorbers, their absorption band and ventilation rate have not yet attained practical application at low frequencies (<1000 Hz). A theoretical and experimental demonstration of a reconfigurable ultra-sparse ventilated metamaterial absorber for low frequencies with highly sparse ventilation and tunability is presented. The acoustic absorber is based on triadic cylindrical Helmholtz resonators, and a coupled mode theory for three resonators is implemented to elucidate the underlying physics. The absorber achieves a sparsity level of more than 80%, with a measured wind velocity ratio higher than 95%. Furthermore, tunability is accomplished in the frequency range of 600 to 950 Hz through reconfiguration. Due to its simple structure, this metamaterial absorber can be easily fabricated in mass in the future, providing promising solutions for various acoustic engineering applications

Table_1_Associations between omega-3 fatty acids and insulin resistance and body composition in women with polycystic ovary syndrome.DOCX

BackgroundPolycystic ovary syndrome (PCOS) is strongly associated with abdominal obesity and insulin resistance and effective approaches to nutrition (e.g., omega-3 fatty acids intake) might improve the cardiometabolic risk profile. This study aimed to examine the associations of dietary and serum omega-3 fatty acids with insulin resistance (IR) and body composition among PCOS patients.MethodsA total of 185 patients with PCOS were included in our analysis. Dietary information was collected through face-to-face interviews using a 102-item food frequency questionnaire (FFQ). Serum omega-3 fatty acid levels were measured with the gas chromatography method. Body composition was measured by both dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance (BIA) methods. The multivariable linear regression model was applied to analyze the associations of dietary and serum omega-3 fatty acids with the levels of Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) and body composition parameters among PCOS patients.ResultsOur results indicated that the dietary long-chain omega-3 polyunsaturated fatty acids (PUFA) intakes were negatively associated with HOMA-IR (β = –0.089, P = 0.040), fat mass (β = –0.022, P = 0.047), and body fat percentage (β = –0.026, P = 0.032). For serum biomarkers, higher total omega-3 PUFAs levels (β = –0.158, P = 0.021) and long-chain omega-3 PUFAs levels (β = –0.187, P ConclusionHigher levels of dietary and serum omega-3 PUFAs, particularly long-chain omega PUFAs (DPA and DHA), might have beneficial effects on metabolic parameters and body composition among PCOS patients.</p