Vascular Risk Factor Prevalence and Trends in Native Americans With Ischemic Stroke - A National Inpatient Sample Analysis

IntroductionNative Americans have a higher incidence and prevalence of stroke and the highest stroke-related mortality among race-ethnic groups in the United States. We aimed to analyze trends in the prevalence of vascular risk factors among Native Americans with ischemic stroke over the last two decades along with a comparison to the other race-ethnic groups.MethodsNational/Nationwide Inpatient Sample (NIS) database was used to explore the prevalence of risk factors among hospitalized ischemic stroke patients during 2000 - 2016. Ischemic stroke and risk factors of interest were identified using validated ICD-9/10 codes. The race-ethnic groups of interest were Native American, White, Black, Hispanic, Asian/Pacific Islanders, and others. Crude and age-and sex-standardized prevalence estimates were calculated for each risk factor within each race-ethnic group in 6 time periods: 2000-02, 2003-05, 2006-08, 2009-11, 2012-14, and 2015-16. We explored linear trends over the defined time periods using linear regression models, with differences in trends between the Native American group and each of the other race-ethnic groups assessed using interaction terms. The analysis accounted for the complex sampling design, including hospital clusters, NIS stratum, and trend weights for analyzing multiple years of NIS data.ResultsOf the 1,278,784 ischemic stroke patients that were included in the analysis, Native Americans constituted 5472. The age-and-sex-standardized prevalence of hypertension (trend slope = 2.24, p < 0.001), hyperlipidemia (trend slope = 6.29, p < 0.001), diabetes (trend slope = 2.04, p = 0.005), atrial fibrillation/flutter (trend slope = 0.80, p = 0.011), heart failure (trend slope = 0.73, p = 0.036) smoking (trend slope = 3.65, p < 0.001), and alcohol (slope = 0.60, p = 0.019) increased during these time periods among Native Americans, while coronary artery disease prevalence remained unchanged. Similar upward trends of several risk factors were noted across other race-ethnic groups with Native Americans showing larger increases in hypertension prevalence compared to Blacks, Hispanics, and Asian/Pacific Islanders and in smoking prevalence compared to Hispanics and Asian/Pacific Islanders. By the year 2015-2016, Native Americans had the highest overall prevalence of diabetes, coronary artery disease, smoking, and alcohol among all the race-ethnic groups.ConclusionThe prevalence of most vascular risk factors among ischemic stroke patients has increased in Native Americans and other race-ethnic groups over the last two decades. Significantly larger increases in the prevalence of hypertension and smoking were seen in Native Americans compared to other groups along with them having the highest prevalence in multiple risk factors in recent years.

Spatial Distribution of NDVI Trends for Forest Vegetation in the Natural Reserve “Stolby” Based on MODIS Satellite Data

The purpose of this work is to assess the long-term changes in the state of forest vegetation on the territory of the Nature Reserve “Stolby” for the period 2000-2018. An algorithm has been developed for this and a map of the spatial distribution of the average annual NDVI trends of forest vegetation according to MODIS satellite data has been created (May – September as averaging period). In the work, a map of vegetation cover was used according to the electronic ecological atlas of the Nature Reserve “Stolby”. The analysis of the distribution of the number of pixels on the values of the average annual NDVI trend revealed that for the class of coniferous vegetation negative values of the linear trend prevail (by 30%). For the deciduous vegetation class, the number of pixels with negative values of linear trend slope is 3.1% higher than with positive ones. In general, for most types of forest vegetation negative trends NDVI prevail. The negative NDVI trend slope of vegetation indicates degradation processes. The reasons for this are the changes of climatic factors, anthropogenic impact, fires, aging and forest vegetation diseases

Spatial and Temporal Patterns of the Extreme Precipitation across the Tibetan Plateau (1986–2015)

The Tibetan Plateau is one of the most vulnerable areas to extreme precipitation. In recent decades, water cycles have accelerated, and the temporal and spatial characteristics of extreme precipitation have undergone dramatic changes across the Tibetan Plateau, especially in its various ecosystems. However, there are few studies that considered the variation of extreme precipitation in various ecosystems, and the impact of El Niño-Southern Oscillation (ENSO), and few researchers have made a quantitative analysis between them. In this study, we analyzed the spatial and temporal pattern of 10 extreme precipitation indices across the Tibetan Plateau (including its four main ecosystems: Forest, alpine meadow, alpine steppe, and desert steppe) based on daily precipitation from 76 meteorological stations over the past 30 years. We used the linear least squares method and Pearson correlation coefficient to examine variation magnitudes of 10 extreme precipitation indices and correlation. Temporal pattern indicated that consecutive wet days (CWD) had a slightly decreasing trend (slope = −0.006), consecutive dry days (CDD), simple daily intensity (SDII), and extreme wet day precipitation (R99) displayed significant increasing trends, while the trends of other indices were not significant. For spatial patterns, the increasing trends of nine extreme precipitation indices (excluding CDD) occurred in the southwestern, middle and northern regions of the Tibetan Plateau; decreasing trends were distributed in the southeastern region, while the spatial pattern of CDD showed the opposite distribution. As to the four different ecosystems, the number of moderate precipitation days (R10mm), number of heavy precipitation days (R20mm), wet day precipitation (PRCPTOT), and very wet day precipitation (R95) in forest ecosystems showed decreasing trends, but CDD exhibited a significant increasing trend (slope = 0.625, P < 0.05). In the other three ecosystems, all extreme precipitation indices generally exhibited increasing trends, except for CWD in alpine meadow (slope = −0.001) and desert steppe (slope = −0.005). Furthermore, the crossover wavelet transform indicated that the ENSO had a 4-year resonance cycle with R95, SDII, R20mm, and CWD. These results provided additional evidence that ENSO play an important remote driver for extreme precipitation variation in the Tibetan Plateau.

Seasonal and Annual Trends of Rainfall and Streamflow in the Mae Klong Basin, Thailand

This study examined seasonal and annual trends of rainfall and streamflow data in the Mae Klong Basin, Thailand. Monthly data of eight key rainfall stations and ten streamflow stations were analyzed to detect trends using the non-parametric Mann-Kendall test, whilst the magni-tude of the trends was determined by Sen’s slope method for the period 2000-2015. For 75% ofthe analyzed stations,rainfall was found to increase in the wet season and decrease in the dry season. Station 130013 situated in the lower region showed a statistically significant increasing trend with a trend slope of 16.02 mma-1in the wet season, while station 130042-also located in the lower region of the basin-showed a statistically significant decreasing trend, with a trend slope of23.60 mma-1in the dry season. On an annual basis, 63%of the analyzed stations showed increasing rainfall trends, particularly in the central and lower regions of the Mae Klong Basin; however, rainfall trends in the upper region were found to be decreasing, which reflected water contributions to two main reservoirs in the upper part. The trends of naturalized inflow of Srinagarind and Vajiralongkorn Reservoirs were found to be decreasing on both seasonal and annual bases, while two naturalized streamflow stations located in Lam Taphoen and Lampachi sub-basins in the central and lower regions, respectively, showed increasing trends in both dry and wet seasons. The trends of regulated streamflow stations downstream of 4 main dams which were a result of reservoir operation were found to mostly decrease on an annual scale. Results of this study can help water resources managers enhance accuracy of assessment and effective planning of water resources management in the basin.

Auditory and Visual Reaction Time in Adults during Long Performance

Better to understand the relation of auditory to visual reaction time (RT) tasks during a long period (320 min.) as well as the evolution of these performances along time, 24 subjects were tested. RT tasks were delivered at 10-min. intervals for 320 min. Correlations between auditory and visual RTs and cross-correlation functions were calculated. Our results confirmed their association, which was maintained throughout the experiment. There were no significant differences in the mean RT by sex or time of day; however, differences were found for the trend slope between type of stimulus and sex.