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Discover the most talked about and latest scientific content & concepts.

Concept: American Civil War

103

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

45

Over the past 500 years, North America has been the site of ongoing mixing of Native Americans, European settlers, and Africans (brought largely by the trans-Atlantic slave trade), shaping the early history of what became the United States. We studied the genetic ancestry of 5,269 self-described African Americans, 8,663 Latinos, and 148,789 European Americans who are 23andMe customers and show that the legacy of these historical interactions is visible in the genetic ancestry of present-day Americans. We document pervasive mixed ancestry and asymmetrical male and female ancestry contributions in all groups studied. We show that regional ancestry differences reflect historical events, such as early Spanish colonization, waves of immigration from many regions of Europe, and forced relocation of Native Americans within the US. This study sheds light on the fine-scale differences in ancestry within and across the United States and informs our understanding of the relationship between racial and ethnic identities and genetic ancestry.

Concepts: United States, Race, Native Americans in the United States, North America, Caribbean, American Civil War, European American, English American

37

Innovative approaches are needed to promote physical activity among young adult overweight and obese African American women. We sought to describe key elements that African American women desire in a culturally relevant Internet-based tool to promote physical activity among overweight and obese young adult African American women.

Concepts: Obesity, Physical exercise, Overweight, African American, Native Americans in the United States, Southern United States, American Civil War, Jim Crow laws

36

More prehistoric trepanned crania have been found in Peru than any other location worldwide. We examine trepanation practices and outcomes in Peru over nearly 2000 years from 400 BC to provide a perspective on the procedure with comparison to procedures/outcomes of other ancient, medieval and American-Civil-War cranial surgery. . Data on trepanation demographics, techniques, and survival rates were collected through the scientific analysis of more than 800 trepanned crania discovered in Peru, through field studies and the courtesy of museums and private collections in the U.S. and Peru, over nearly 3 decades. Data on procedures and outcomes of cranial surgery ancient, medieval and during 19th-century through the American-Civil-war were obtained via a literature review. Successful trepanations from prehistoric times through the American Civil War likely involved shallow surgeries that did not pierce the dura mater. While there are regional and temporal variations in ancient Peru, overall long-term survival rates for the study series were about 40% in the earliest period (400-200 BC), with improvement to a high of 91% in samples from AD 1000-1400, to an average of 75-83% during the Inca Period (AD 1400s-1500). In comparison,the average cranial surgery mortality rate during the American Civil war was 46-56%, and short and long-term survival rates are unknown. The contrast in outcomes highlights the astonishing success of ancient cranial surgery in Peru in the treatment of living patients.

Concepts: Time, United States, Al-Andalus, American Civil War, Civil war, Inca Empire, Inca, Franklin Pierce

32

We examined neonatal mortality in relation to birth settings and birth attendants in the United States from 2006-2009.

Concepts: United States, Milk, Poverty in the United States, U.S. state, Infant mortality, Setting, American Civil War

32

Objectives. Medical marijuana laws (MMLs) have been suggested as a possible cause of increases in marijuana use among adolescents in the United States. We evaluated the effects of MMLs on adolescent marijuana use from 2003 through 2011. Methods. We used data from the Youth Risk Behavior Survey and a difference-in-differences design to evaluate the effects of passage of state MMLs on adolescent marijuana use. The states examined (Montana, Rhode Island, Michigan, and Delaware) had passed MMLs at different times over a period of 8 years, ensuring that contemporaneous history was not a design confound. Results. In 40 planned comparisons of adolescents exposed and not exposed to MMLs across states and over time, only 2 significant effects were found, an outcome expected according to chance alone. Further examination of the (nonsignificant) estimates revealed no discernible pattern suggesting an effect on either self-reported prevalence or frequency of marijuana use. Conclusions. Our results suggest that, in the states assessed here, MMLs have not measurably affected adolescent marijuana use in the first few years after their enactment. Longer-term results, after MMLs are more fully implemented, might be different. (Am J Public Health. Published online ahead of print June 13, 2013: e1-e7. doi:10.2105/AJPH.2012.301117).

Concepts: Effect, United States, U.S. state, Cannabis, Massachusetts, American Civil War, Law of the United States, Legality of cannabis by country

29

The steep rise in U.S. criminal punishment in recent decades has spurred scholarship on the collateral consequences of imprisonment for individuals, families, and communities. Several excellent studies have estimated the number of people who have been incarcerated and the collateral consequences they face, but far less is known about the size and scope of the total U.S. population with felony convictions beyond prison walls, including those who serve their sentences on probation or in jail. This article develops state-level estimates based on demographic life tables and extends previous national estimates of the number of people with felony convictions to 2010. We estimate that 3 % of the total U.S. adult population and 15 % of the African American adult male population has ever been to prison; people with felony convictions account for 8 % of all adults and 33 % of the African American adult male population. We discuss the far-reaching consequences of the spatial concentration and immense growth of these groups since 1980.

Concepts: Mathematics, United States, Criminal law, Prison, Caribbean, Punishment, American Civil War, Felony

28

Confirmed local transmission of Zika Virus (ZIKV) in Texas and Florida have heightened the need for early and accurate indicators of self-sustaining transmission in high risk areas across the southern United States. Given ZIKV’s low reporting rates and the geographic variability in suitable conditions, a cluster of reported cases may reflect diverse scenarios, ranging from independent introductions to a self-sustaining local epidemic.

Concepts: United States, U.S. state, Florida, Native Americans in the United States, Southern United States, Texas, American Civil War, Confederate States of America

28

Smoke-free air laws in restaurants and bars protect patrons and workers from involuntary exposure to secondhand smoke, but owners often express concern that such laws will harm their businesses. The primary objective of this study was to estimate the association between local smoke-free air laws and economic outcomes in restaurants and bars in 8 states without statewide smoke-free air laws: Alabama, Indiana, Kentucky, Mississippi, Missouri, South Carolina, Texas, and West Virginia. A secondary objective was to examine the economic impact of a 2010 statewide smoke-free restaurant and bar law in North Carolina.

Concepts: U.S. state, Native Americans in the United States, Southern United States, American Civil War, Confederate States of America, Tennessee, Oak Ridge Associated Universities, States of the United States

28

In this article, we demonstrate the application of a new compressed sensing three-dimensional reconstruction algorithm for electron tomography that increases the accuracy of morphological characterization of nanostructured materials such as nanocrystalline iron oxide particles. A powerful feature of the algorithm is an anisotropic total variation norm for the L1 minimization during algebraic reconstruction that effectively reduces the elongation artifacts caused by limited angle sampling during electron tomography. The algorithm provides faithful morphologies that have not been feasible with existing techniques.

Concepts: Medical imaging, Nanomaterials, Tomography, Reconstruction algorithm, Discrete tomography, American Civil War, Total variation