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Significant Decreasing Trends (significant + decreasing_trend)
Selected AbstractsAdiponectin and type 2 diabetes in Samoan adultsAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2009Julia R. Dibello Objective: Previous studies have established an association between adiponectin and type 2 diabetes. It is unclear whether adiponectin will be useful among Samoan Islanders, characterized by markedly elevated levels of obesity, in differentiating those at risk of developing type 2 diabetes. Methods: Cross-sectional, genetic epidemiology study of obesity in American Samoa and Samoa 2002,2003 (n = 1,599). Logistic regression provided adjusted odds ratios and 95% confidence intervals for the association between adiponectin, diabetes, and prediabetes (impaired fasting glucose). Results: There is a significant decreasing trend in the odds of diabetes and prediabetes across increasing quintiles of adiponectin with an OR of 2.8 (95% CI: 1.6, 5.0) and 2.9 (95% CI: 1.5, 5.7), respectively, in the lowest relative to the highest quintile of adiponectin (P -for-trend = 0.004 and 0.001). Conclusions: Adiponectin is an important correlate, independent of other risk factors, of the pathogenesis of type 2 diabetes among Samoan islanders and may help distinguish those at higher risk of developing this disease. Am. J. Hum. Biol. 2009. © 2008 Wiley-Liss, Inc. [source] The greening and browning of Alaska based on 1982,2003 satellite dataGLOBAL ECOLOGY, Issue 4 2008David Verbyla Abstract Aim To examine the trends of 1982,2003 satellite-derived normalized difference vegetation index (NDVI) values at several spatial scales within tundra and boreal forest areas of Alaska. Location Arctic and subarctic Alaska. Methods Annual maximum NDVI data from the twice monthly Global Inventory Modelling and Mapping Studies (GIMMS) NDVI 1982,2003 data set with 64-km2 pixels were extracted from a spatial hierarchy including three large regions: ecoregion polygons within regions, ecozone polygons within boreal ecoregions and 100-km climate station buffers. The 1982,2003 trends of mean annual maximum NDVI values within each area, and within individual pixels, were computed using simple linear regression. The relationship between NDVI and temperature and precipitation was investigated within climate station buffers. Results, At the largest spatial scale of polar, boreal and maritime regions, the strongest trend was a negative trend in NDVI within the boreal region. At a finer scale of ecoregion polygons, there was a strong positive NDVI trend in cold arctic tundra areas, and a strong negative trend in interior boreal forest areas. Within boreal ecozone polygons, the weakest negative trends were from areas with a maritime climate or colder mountainous ecozones, while the strongest negative trends were from warmer basin ecozones. The trends from climate station buffers were similar to ecoregion trends, with no significant trends from Bering tundra buffers, significant increasing trends among arctic tundra buffers and significant decreasing trends among interior boreal forest buffers. The interannual variability of NDVI among the arctic tundra buffers was related to the previous summer warmth index. The spatial pattern of increasing tundra NDVI at the pixel level was related to the west-to-east spatial pattern in changing climate across arctic Alaska. There was no significant relationship between interannual NDVI and precipitation or temperature among the boreal forest buffers. The decreasing NDVI trend in interior boreal forests may be due to several factors including increased insect/disease infestations, reduced photosynthesis and a change in root/leaf carbon allocation in response to warmer and drier growing season climate. Main conclusions There was a contrast in trends of 1982,2003 annual maximum NDVI, with cold arctic tundra significantly increasing in NDVI and relatively warm and dry interior boreal forest areas consistently decreasing in NDVI. The annual maximum NDVI from arctic tundra areas was strongly related to a summer warmth index, while there were no significant relationships in boreal areas between annual maximum NDVI and precipitation or temperature. Annual maximum NDVI was not related to spring NDVI in either arctic tundra or boreal buffers. [source] Problems in evaluating regional and local trends in temperature: an example from eastern Colorado, USAINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2002R. A. Pielke SR Abstract We evaluated long-term trends in average maximum and minimum temperatures, threshold temperatures, and growing season in eastern Colorado, USA, to explore the potential shortcomings of many climate-change studies that either: (1) generalize regional patterns from single stations, single seasons, or a few parameters over short duration from averaging dissimilar stations; or (2) generalize an average regional pattern from coarse-scale general circulation models. Based on 11 weather stations, some trends were weakly regionally consistent with previous studies of night-time temperature warming. Long-term (80 + years) mean minimum temperatures increased significantly (P < 0.2) in about half the stations in winter, spring, and autumn and six stations had significant decreases in the number of days per year with temperatures , , 17.8 °C (,0 °F). However, spatial and temporal variation in the direction of change was enormous for all the other weather parameters tested, and, in the majority of tests, few stations showed significant trends (even at P < 0.2). In summer, four stations had significant increases and three stations had significant decreases in minimum temperatures, producing a strongly mixed regional signal. Trends in maximum temperature varied seasonally and geographically, as did trends in threshold temperature days ,32.2 °C (,90 °F) or days ,37.8 °C (,100 °F). There was evidence of a sub-regional cooling in autumn's maximum temperatures, with five stations showing significant decreasing trends. There were many geographic anomalies where neighbouring weather stations differed greatly in the magnitude of change or where they had significant and opposite trends. We conclude that sub-regional spatial and seasonal variation cannot be ignored when evaluating the direction and magnitude of climate change. It is unlikely that one or a few weather stations are representative of regional climate trends, and equally unlikely that regionally projected climate change from coarse-scale general circulation models will accurately portray trends at sub-regional scales. However, the assessment of a group of stations for consistent more qualitative trends (such as the number of days less than ,17.8 °C, such as we found) provides a reasonably robust procedure to evaluate climate trends and variability. Copyright © 2002 Royal Meteorological Society [source] Prevalence of human papillomavirus genotypes in women from three clinical settingsJOURNAL OF MEDICAL VIROLOGY, Issue 1 2005Anil K. Chaturvedi Abstract Prevalence of 27 human papillomavirus (HPV) genotypes was assessed in 1,331 women in three clinical settings: Family planning clinic (low-risk HIV,, n,=,202, 21.3% HPV+), colposcopy clinic (high-risk HIV,, n,=,854, 34.3% HPV+), and HIV outpatient clinic (HIV+, n,=,275, 48.7% HPV+). Compared to women from both family planning and colposcopy clinics, HIV+ women revealed significantly higher prevalence of infection with oncogenic, non-oncogenic, and multiple HPV types. HPV types 52 and 51 were most prevalent in the low-risk HIV, women, whereas in the high-risk HIV, women, HPV types 16, 52, 58, and 35 were most prevalent. Interestingly, in the HIV+ women, less characterized types 83, 53, and 54 were most prevalent. The distinct profiles of genotype prevalence persisted after stratification by Pap smear status. After adjustment for concurrent infections with other types, HPV type 51 in the low-risk HIV, women, and types 16, 35, 39, 45, 52, and 58 in the high-risk HIV, women were significantly associated with cytologic abnormalities (exact P,<,0.05). In HIV+ women across CD4 cell count strata, HPV types 42, 16, and 82 revealed significant decreasing trends with increasing CD4 counts (exact P for trend,<,0.05). These data suggest distinct genotypic prevalence profiles in women at diverse risk for cervical cancer. The association of several genotypes with cytologic abnormalities underscores the need for vaccines targeting a wide range of HPV types. J. Med. Virol. 75:105,113, 2005. © 2005 Wiley-Liss, Inc. [source] | ||||||||||