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Concept: Population history of American indigenous peoples


Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact.

Concepts: Demography, United States, Native Americans in the United States, Indigenous peoples, Indigenous peoples of the Americas, New Mexico, European colonization of the Americas, Population history of American indigenous peoples


INTRODUCTION:: Colonic volvulus is a rare entity associated with high mortality rates. Most studies come from areas of high endemicity and are limited by small numbers. No studies have investigated trends, outcomes, and predictors of mortality at the national level. METHODS:: The Nationwide Inpatient Sample 2002-2010 was retrospectively reviewed for colonic volvulus cases admitted emergently. Patients' demographics, hospital factors, and outcomes of the different procedures were analyzed. The LASSO algorithm for logistic regression was used to build a predictive model for mortality in cases of sigmoid (SV) and cecal volvulus (CV) taking into account preoperative and operative variables. RESULTS:: An estimated 3,351,152 cases of bowel obstruction were admitted in the United States over the study period. Colonic volvulus was found to be the cause in 63,749 cases (1.90%). The incidence of CV increased by 5.53% per year whereas the incidence of SV remained stable. SV was more common in elderly males (aged 70 years), African Americans, and patients with diabetes and neuropsychiatric disorders. In contrast, CV was more common in younger females. Nonsurgical decompression alone was used in 17% of cases. Among cases managed surgically, resective procedures were performed in 89% of cases, whereas operative detorsion with or without fixation procedures remained uncommon. Mortality rates were 9.44% for SV, 6.64% for CV, 17% for synchronous CV and SV, and 18% for transverse colon volvulus. The LASSO algorithm identified bowel gangrene and peritonitis, coagulopathy, age, the use of stoma, and chronic kidney disease as strong predictors of mortality. CONCLUSIONS:: Colonic volvulus is a rare cause of bowel obstruction in the United States and is associated with high mortality rates. CV and SV affect different populations and the incidence of CV is on the rise. The presence of bowel gangrene and coagulopathy strongly predicts mortality, suggesting that prompt diagnosis and management are essential.

Concepts: Chronic kidney disease, Epidemiology, United States, U.S. state, Bowel obstruction, Native Americans in the United States, Volvulus, Population history of American indigenous peoples


Climate’s influence on late Pre-Columbian (pre-1492 CE), maize-dependent Native American populations in the midcontinental United States (US) is poorly understood as regional paleoclimate records are sparse and/or provide conflicting perspectives. Here, we reconstruct regional changes in precipitation source and seasonality and local changes in warm-season duration and rainstorm events related to the Pacific North American pattern (PNA) using a 2100-year-long multi-proxy lake-sediment record from the midcontinental US. Wet midcontinental climate reflecting negative PNA-like conditions occurred during the Medieval Climate Anomaly (950-1250 CE) as Native American populations adopted intensive maize agriculture, facilitating population aggregation and the development of urban centers between 1000-1200 CE. Intensifying midcontinental socio-political instability and warfare between 1250-1350 CE corresponded with drier positive PNA-like conditions, culminating in the staggered abandonment of many major Native American river valley settlements and large urban centers between 1350-1450 CE during an especially severe warm-season drought. We hypothesize that this sustained drought interval rendered it difficult to support dense populations and large urban centers in the midcontinental US by destabilizing regional agricultural systems, thereby contributing to the host of socio-political factors that led to population reorganization and migration in the midcontinent and neighboring regions shortly before European contact.

Concepts: Agriculture, United States, Precipitation, Native Americans in the United States, North America, Americas, Indigenous peoples of the Americas, Population history of American indigenous peoples


Overall mortality rates from coronary heart disease (CHD) in the United States have declined in recent decades, but the rate has plateaued among younger women. The potential for further reductions in mortality rates among young women through changes in lifestyle is unknown.

Concepts: Epidemiology, Heart, United States, Heart disease, Poverty in the United States, U.S. state, Native Americans in the United States, Population history of American indigenous peoples


BACKGROUND: Indigenous peoples of Australia, Canada, United States and New Zealand experience disproportionately high rates of suicide. As such, the methodological quality of evaluations of suicide prevention interventions targeting these Indigenous populations should be rigorously examined, in order to determine the extent to which they are effective for reducing rates of Indigenous suicide and suicidal behaviours. This systematic review aims to: 1) identify published evaluations of suicide prevention interventions targeting Indigenous peoples in Australia, Canada, United States and New Zealand; 2) critique their methodological quality; and 3) describe their main characteristics. METHODS: A systematic search of 17 electronic databases and 13 websites for the period 1981–2012 (inclusive) was undertaken. The reference lists of reviews of suicide prevention interventions were hand-searched for additional relevant studies not identified by the electronic and web search. The methodological quality of evaluations of suicide prevention interventions was assessed using a standardised assessment tool. RESULTS: Nine evaluations of suicide prevention interventions were identified: five targeting Native Americans; three targeting Aboriginal Australians; and one First Nation Canadians. The main intervention strategies employed included: Community Prevention, Gatekeeper Training, and Education. Only three of the nine evaluations measured changes in rates of suicide or suicidal behaviour, all of which reported significant improvements. The methodological quality of evaluations was variable. Particular problems included weak study designs, reliance on self-report measures, highly variable consent and follow-up rates, and the absence of economic or cost analyses. CONCLUSIONS: There is an urgent need for an increase in the number of evaluations of preventive interventions targeting reductions in Indigenous suicide using methodologically rigorous study designs across geographically and culturally diverse Indigenous populations. Combining and tailoring best evidence and culturally-specific individual strategies into one coherent suicide prevention program for delivery to whole Indigenous communities and/or population groups at high risk of suicide offers considerable promise.

Concepts: United States, Australia, Native Americans in the United States, Latin America, Indigenous Australians, Indigenous peoples, Indigenous peoples of the Americas, Population history of American indigenous peoples


We analyzed trends in US female mortality rates by decade from 1900 through 2010, assessed age and racial differences, and proposed explanations and considered implications.

Concepts: Human, United States, Poverty in the United States, U.S. state, Race, Native Americans in the United States, Indigenous peoples of the Americas, Population history of American indigenous peoples


Tuberculosis continues to disproportionately affect many Indigenous populations in the USA, Canada, and Greenland. We aimed to investigate whether population-based tuberculosis-specific interventions or changes in general health and socioeconomic indicators, or a combination of these factors, were associated with changes in tuberculosis incidence in these Indigenous populations.

Concepts: Hawaii, United States, Atlantic Ocean, North America, Latin America, Indigenous peoples of the Americas, Population history of American indigenous peoples


Collisions and electrocutions at power lines are thought to kill large numbers of birds in the United States annually. However, existing estimates of mortality are either speculative (for electrocution) or based on extrapolation of results from one study to all U.S. power lines (for collision). Because national-scale estimates of mortality and comparisons among threats are likely to be used for prioritizing policy and management strategies and for identifying major research needs, these estimates should be based on systematic and transparent assessment of rigorously collected data. We conducted a quantitative review that incorporated data from 14 studies meeting our inclusion criteria to estimate that between 12 and 64 million birds are killed each year at U.S. power lines, with between 8 and 57 million birds killed by collision and between 0.9 and 11.6 million birds killed by electrocution. Sensitivity analyses indicate that the majority of uncertainty in our estimates arises from variation in mortality rates across studies; this variation is due in part to the small sample of rigorously conducted studies that can be used to estimate mortality. Little information is available to quantify species-specific vulnerability to mortality at power lines; the available literature over-represents particular bird groups and habitats, and most studies only sample and present data for one or a few species. Furthermore, additional research is needed to clarify whether, to what degree, and in what regions populations of different bird species are affected by power line-related mortality. Nonetheless, our data-driven analysis suggests that the amount of bird mortality at U.S. power lines is substantial and that conservation management and policy is necessary to reduce this mortality.

Concepts: Evolution, Sample size, United States, Bird, Native Americans in the United States, KILL, Indigenous peoples of the Americas, Population history of American indigenous peoples


Young Indigenous people, particularly those involved in the child welfare system, those entrenched in substance use and those living with HIV or hepatitis C, are dying prematurely. We report mortality rates among young Indigenous people who use drugs in British Columbia and explore predictors of mortality over time.

Concepts: United States, Native Americans in the United States, Pacific Northwest, Indigenous peoples, Indigenous peoples of the Americas, First Nations, European colonization of the Americas, Population history of American indigenous peoples


Six decades ago the DI*A allele of the Diego blood group system was instrumental in proving Native American populations originated from Siberia. Since then, it has received scant attention. The present study was undertaken to reappraise distribution of the DI*A allele in 144 Native American populations based on current knowledge. Using analysis of variance tests, frequency distribution was studied according to geographical, environmental, and cultural parameters. Frequencies were highest in Amazonian populations. In contrast, DI*A was undetectable in subarctic, Fuegian, Panamanian, Chaco and Yanomama populations. Closer study revealed a correlation that this unequal distribution was correlated with language, suggesting that linguistic divergence was a driving force in the expansion of DI*A among Native Americans. The absence of DI*A in circumpolar Eskimo-Aleut and Na-Dene speakers was consistent with a late migratory event confined to North America. Distribution of DI*A in subtropical areas indicated that gene and culture exchanges were more intense within than between ecozones. Bolstering the utility of classical genetic markers in biological anthropology, the present study of the expansion of Diego blood group genetic polymorphism in Native Americans shows strong evidence of gene-culture comigration.

Concepts: Gene, Genetics, Allele, United States, Native Americans in the United States, North America, Indigenous peoples of the Americas, Population history of American indigenous peoples