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Background: There have been conflicting reports comparing the prevalence of large polyps (>9 mm) between Hispanics and non-Hispanic whites (NHW). Differences between Hispanic subpopulations may account for these variations.Aims: We aimed to assess the prevalence of large polyps (>9 mm) in Hispanics from Mexican- and non-Mexican-predominant states compared with NHW. As secondary outcome, we evaluated results by polyp location.Methods: The 2010 U.S. Census Bureau was used to identify states with a predominantly Mexican Hispanic (West) versus non-Mexican Hispanic (East) populations. Average-risk colonoscopies in those states from 2001 to 2014 were accessed using the Clinical Outcomes Research Initiative database. Military and Veteran's Administration sites were excluded. Hispanics were compared with NHW in each geographical location using hierarchical logistic regression analysis.Results: A total of 65,138 procedures were included with 33,425 procedures in the West (14.5% Hispanics) and 31,713 procedures in the East (44.0% Hispanics,). East Hispanics had significantly less odds of large polyps, OR 0.74, CI 0.58-0.94, p = 0.02, while West Hispanics exhibited no difference, OR 0.91, CI 0.76-1.10, p = 0.33, compared with NHW. Eastern Hispanics had less odds of large distal polyps, OR 0.69, CI 0.52-0.91, p = 0.01, and no difference in proximal polyps compared with NHW. Among Western Hispanics, no differences were seen in proximal, OR 1.06, CI 0.83-1.35, p = 0.66, or distal polyps, OR 0.83, CI 0.68-1.02, p = 0.08, compared with NHW.Conclusion: Using NHW as a reference, Hispanics from Mexican-predominant states have a similar prevalence of large polyps, while Hispanics from non-Mexican-predominant states have a lower prevalence. Differences in Hispanic subpopulations likely explain previous conflicting reports on the prevalence of large polyps in Hispanics and NHW. [ABSTRACT FROM AUTHOR]

The bullfrog is one of the most aggressive invasive species globally because of their wide dispersal ability, competence and their voracious eating habits. In Colombia, the species has been reported since the early 80's when entered the country as an economic alternative in the frog breeding and distribution has increased since then. This work has modeled potential distribution of the species in Colombia based upon the projection of the distribution in the native area in the northeastern United States. Likewise, the distribution was compared with the current potential future distribution of three global circulation models (CCCMA-CGCM31, CSIRO_MK30 and IPSL_CM4) and over two time horizons (2050 and 2080 yrs). It was determined that the Andes and the Caribbean Region in Colombia presents optimal areas for the establishment of the species present and the future. It is urgent to design and implement a management and control plan for Bullfrog populations in Colombia, to identify invaded areas and perform control of this species. This article provides some basis for the development of this plan in Colombia. [ABSTRACT FROM AUTHOR]

Highlights • Differences exist between the performances of various drought indices used to identify drought impacts on crop yields. • Multiscalar drought indices outperform uniscalar drought indices for monitoring the impact of drought on crop yields. • Shorter drought time-scales are better at identifying drought impacts on crop yields. Abstract This article presents an analysis of the response of the annual crop yield in five main dryland cultivations in the United States to different time-scales of drought, and explores the environmental and climatic characteristics that determine the response. For this purpose we analysed barley, winter wheat, soybean, corn and cotton. Drought was quantified by means of the Standardized Precipitation Evapotranspiration Index (SPEI). The results demonstrate a strong response in the interannual variability of crop yields to the drought time-scales in the different cultivations. Moreover, the response is highly spatially variable. Crop types showed considerable differences in the month in which their yields are most strongly linked to drought conditions. Some crops (e.g. winter wheat) responded to drought at medium to long SPEI time-scales, while other crops (e.g. soybean and corn) responded to short or long drought time-scales. The study confirms that the differences in the patterns of crop yield response to drought time-scales are mostly controlled by average climate conditions, in general, and water availability (precipitation), in particular. Generally, we found that there is a weaker link between crop yield and drought severity in humid environments and also that the response tends to occur over longer time-scales. [ABSTRACT FROM AUTHOR]

Highlights • Climate droughts control hydrological drought severity. • Hydrological droughts are complex and non-stationary. • In the U.S. there are very different patterns of hydrological drought responses. • Natural basins are characterized by different environmental conditions. Abstract We analyzed the relationships between meteorological drought and hydrological drought using very dense and diverse network of gauged natural drainage basins across the conterminous U.S. Specifically, this work utilized a dataset of 289 gauging stations, covering the period 1940–2013. Drainage basins were obtained for each gauging station using a digital terrain model. In addition to meteorological data (e.g., precipitation, air temperature and the atmospheric evaporative demand), we obtained a number of topographic, soil and remote sensing variables for each defined drainage basin. A hydrological drought index (the Standardized Streamflow Index; SSI) was computed for each basin and linked to the Standardized Precipitation Evapotranspiration Index (SPEI), which was used as a metric of climatic drought severity. The relationships between different SPEI time-scales and their corresponding SSI were assessed by means of a Pearson correlation coefficient. Also, the general patterns of response of hydrological droughts to climatic droughts were identified using a principal component analysis. Overall, results demonstrate a positive response of SSI to SPEI at shorter time-scales, with strong seasonality and clear spatial differences. We also assessed the role of some climatic and environmental factors in explaining these different responses using a predictive discriminant analysis. Results indicate that elevation and vegetation coverage are the main drivers of the diverse response of SSI to SPEI time-scales. Similar analyses were made for three sub-periods (1940–1964, 1965–1989 and 1989–2013), whose results confirm considerable differences in the response of SSI to SPEI over the past eighty years. [ABSTRACT FROM AUTHOR]

Objectives: The African American population has a higher prevalence of advanced colon adenomas when compared with non-Hispanic whites and Hispanics, but the risk in other black populations has not been evaluated. Although the Afro-Caribbean population is a significant demographic segment in some regions of the United States, the data are limited on the prevalence of colon adenomas in this group and there is no comparison with a non-Hispanic white population. The objective of our study was to compare the prevalence of adenomas in Afro-Caribbean versus non-Hispanic white populations.Methods: A total of 880 Afro-Caribbean patients and 1828 non-Hispanic white patients undergoing their first screening colonoscopy between January 2008 and August 2014 was included in the study.Results: A total of 2708 patients met entry criteria for the study. The adenoma detection rate among Afro-Caribbeans was 29% and 31% among non-Hispanic whites. There was no statistically significant difference in the prevalence of adenomas in the two groups (P = 0.28), and the rate of advanced adenomas also was similar in both groups (8.6% in Afro-Caribbeans, 9.2% in non-Hispanic whites; P = 0.60). A multivariate analysis also found no difference in the occurrence of adenomas (P = 0.60) or advanced adenomas (P = 0.99) between Afro-Caribbeans and non-Hispanic whites.Conclusions: We found a similar adenoma detection rate and advanced adenoma prevalence among Afro-Caribbeans and non-Hispanic whites undergoing their first screening colonoscopy. As such, the Afro-Caribbean population may not have the same risk of colorectal neoplasia as what has been described for African Americans. Based on these results, it is appropriate to initiate colorectal cancer screening for Afro-Caribbeans at age 50 as recommended for non-Hispanic whites. [ABSTRACT FROM AUTHOR]