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Concept: Native Americans in the United States


To promote optimal health and well-being, adults aged 18-60 years are recommended to sleep at least 7 hours each night (1). Sleeping <7 hours per night is associated with increased risk for obesity, diabetes, high blood pressure, coronary heart disease, stroke, frequent mental distress, and all-cause mortality (2-4). Insufficient sleep impairs cognitive performance, which can increase the likelihood of motor vehicle and other transportation accidents, industrial accidents, medical errors, and loss of work productivity that could affect the wider community (5). CDC analyzed data from the 2014 Behavioral Risk Factor Surveillance System (BRFSS) to determine the prevalence of a healthy sleep duration (≥7 hours) among 444,306 adult respondents in all 50 states and the District of Columbia. A total of 65.2% of respondents reported a healthy sleep duration; the age-adjusted prevalence of healthy sleep was lower among non-Hispanic blacks, American Indians/Alaska Natives, Native Hawaiians/Pacific Islanders, and multiracial respondents, compared with non-Hispanic whites, Hispanics, and Asians. State-based estimates of healthy sleep duration prevalence ranged from 56.1% in Hawaii to 71.6% in South Dakota. Geographic clustering of the lowest prevalence of healthy sleep duration was observed in the southeastern United States and in states along the Appalachian Mountains, and the highest prevalence was observed in the Great Plains states. More than one third of U.S. respondents reported typically sleeping <7 hours in a 24-hour period, suggesting an ongoing need for public awareness and public education about sleep health; worksite shift policies that ensure healthy sleep duration for shift workers, particularly medical professionals, emergency response personnel, and transportation industry personnel; and opportunities for health care providers to discuss the importance of healthy sleep duration with patients and address reasons for poor sleep health.

Concepts: Health care, Health care provider, Medicine, Hypertension, United States, Native Americans in the United States, Great Plains, South Dakota


The economic and ecological costs of wildfire in the United States have risen substantially in recent decades. Although climate change has likely enabled a portion of the increase in wildfire activity, the direct role of people in increasing wildfire activity has been largely overlooked. We evaluate over 1.5 million government records of wildfires that had to be extinguished or managed by state or federal agencies from 1992 to 2012, and examined geographic and seasonal extents of human-ignited wildfires relative to lightning-ignited wildfires. Humans have vastly expanded the spatial and seasonal “fire niche” in the coterminous United States, accounting for 84% of all wildfires and 44% of total area burned. During the 21-y time period, the human-caused fire season was three times longer than the lightning-caused fire season and added an average of 40,000 wildfires per year across the United States. Human-started wildfires disproportionally occurred where fuel moisture was higher than lightning-started fires, thereby helping expand the geographic and seasonal niche of wildfire. Human-started wildfires were dominant (>80% of ignitions) in over 5.1 million km(2), the vast majority of the United States, whereas lightning-started fires were dominant in only 0.7 million km(2), primarily in sparsely populated areas of the mountainous western United States. Ignitions caused by human activities are a substantial driver of overall fire risk to ecosystems and economies. Actions to raise awareness and increase management in regions prone to human-started wildfires should be a focus of United States policy to reduce fire risk and associated hazards.

Concepts: Earth, United States, Climate, Poverty in the United States, U.S. state, Native Americans in the United States, Economy of the United States, Yellowstone National Park


Mark Siedner and colleagues reflect on the early response to the Ebola epidemic and lessons that can be learned for future epidemics.

Concepts: Epidemiology, African American, Pandemic, Native Americans in the United States, Epidemic, Midwestern United States, Western United States


The population genetic structure of Native Hawaiians has yet to be comprehensively studied, and the ancestral origins of Polynesians remain in question. In this study, we utilized high-resolution genome-wide SNP data and mitochondrial genomes of 148 and 160 Native Hawaiians, respectively, to characterize their population structure of the nuclear and mitochondrial genomes, ancestral origins, and population expansion. Native Hawaiians, who self-reported full Native Hawaiian heritage, demonstrated 78% Native Hawaiian, 11.5% European, and 7.8% Asian ancestry with 99% belonging to the B4 mitochondrial haplogroup. The estimated proportions of Native Hawaiian ancestry for those who reported mixed ancestry (i.e. 75% and 50% Native Hawaiian heritage) were found to be consistent with their self-reported heritage. A significant proportion of Melanesian ancestry (mean = 32%) was estimated in 100% self-reported Native Hawaiians in an ADMIXTURE analysis of Asian, Melanesian, and Native Hawaiian populations of K = 2, where K denotes the number of ancestral populations. This notable proportion of Melanesian admixture supports the “Slow-Boat” model of migration of ancestral Polynesian populations from East Asia to the Pacific Islands. In addition, approximately 1,300 years ago a single, strong expansion of the Native Hawaiian population was estimated. By providing important insight into the underlying population structure of Native Hawaiians, this study lays the foundation for future genetic association studies of this U.S. minority population.

Concepts: DNA, United States, Population genetics, Pacific Ocean, Native Americans in the United States, Polynesia, Native Hawaiians, Polynesians


Approximately 25% of individuals aged 65 years or older in the United States have diabetes mellitus. Diabetes rates in this age group are higher for Asian American and Pacific Islanders (AA/PI) than for whites. We examined racial/ethnic differences in diabetes-related potentially preventable hospitalizations (DRPH) among people aged 65 years or older for Japanese, Chinese, Filipinos, Native Hawaiians, and whites.

Concepts: Hawaii, United States, White American, Pacific Ocean, Native Americans in the United States, Asian American, Native Hawaiians, Guam


Many stem-cell clinics have capitalized on public confusion by selling treatments that are not approved by the FDA, supported by clinical studies, or covered by insurers. Given ambiguous FDA guidelines, these clinics have in effect been operating without regulation.

Concepts: Clinical trial, European Union, United States, Avicenna, Republic of Ireland, Native Americans in the United States, Russia, International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use


In the US Corn Belt, a recent doubling in commodity prices has created incentives for landowners to convert grassland to corn and soybean cropping. Here, we use land cover data from the National Agricultural Statistics Service Cropland Data Layer to assess grassland conversion from 2006 to 2011 in the Western Corn Belt (WCB): five states including North Dakota, South Dakota, Nebraska, Minnesota, and Iowa. Our analysis identifies areas with elevated rates of grass-to-corn/soy conversion (1.0-5.4% annually). Across the WCB, we found a net decline in grass-dominated land cover totaling nearly 530,000 ha. With respect to agronomic attributes of lands undergoing grassland conversion, corn/soy production is expanding onto marginal lands characterized by high erosion risk and vulnerability to drought. Grassland conversion is also concentrated in close proximity to wetlands, posing a threat to waterfowl breeding in the Prairie Pothole Region. Longer-term land cover trends from North Dakota and Iowa indicate that recent grassland conversion represents a persistent shift in land use rather than short-term variability in crop rotation patterns. Our results show that the WCB is rapidly moving down a pathway of increased corn and soybean cultivation. As a result, the window of opportunity for realizing the benefits of a biofuel industry based on perennial bioenergy crops, rather than corn ethanol and soy biodiesel, may be closing in the WCB.

Concepts: Agriculture, Native Americans in the United States, Biofuel, Ethanol fuel, Minnesota, American Bison, South Dakota, National Agricultural Statistics Service


Across Europe, Canada, and the United States, 22-43 % of transgender (trans) people report a history of suicide attempts. We aimed to identify intervenable factors (related to social inclusion, transphobia, or sex/gender transition) associated with reduced risk of past-year suicide ideation or attempt, and to quantify the potential population health impact.

Concepts: LGBT, United States, Sociology, United Kingdom, Canada, Native Americans in the United States, Transgender, Suicide


Pay-for-performance programs are being adopted internationally despite little evidence that they improve patient outcomes. In 2008, a program called Advancing Quality, based on the Hospital Quality Incentive Demonstration in the United States, was introduced in all National Health Service (NHS) hospitals in the northwest region of England (population, 6.8 million).

Concepts: Health insurance, Hospital, United States, U.S. state, National Health Service, England, Native Americans in the United States, Massachusetts


We present a comprehensive assessment of genomic diversity in the African-American population by studying three genotyped cohorts comprising 3,726 African-Americans from across the United States that provide a representative description of the population across all US states and socioeconomic status. An estimated 82.1% of ancestors to African-Americans lived in Africa prior to the advent of transatlantic travel, 16.7% in Europe, and 1.2% in the Americas, with increased African ancestry in the southern United States compared to the North and West. Combining demographic models of ancestry and those of relatedness suggests that admixture occurred predominantly in the South prior to the Civil War and that ancestry-biased migration is responsible for regional differences in ancestry. We find that recent migrations also caused a strong increase in genetic relatedness among geographically distant African-Americans. Long-range relatedness among African-Americans and between African-Americans and European-Americans thus track north- and west-bound migration routes followed during the Great Migration of the twentieth century. By contrast, short-range relatedness patterns suggest comparable mobility of ∼15-16km per generation for African-Americans and European-Americans, as estimated using a novel analytical model of isolation-by-distance.

Concepts: United States, White American, African American, Native Americans in the United States, Southern United States, Texas, American Civil War, English American