Writing Her Way Back to the Old South: History, Memory, and Mildred Lewis

Mildred Lewis Rutherford, as one of the most prominent members of the United Daughters of the Confederacy, has been scantly researched in the past, however her speeches and writing had a profound impact on southern historical consciousness during the New South Period. Her influence, interestingly, was not entirely based in reality. A poststructural analysis of her speeches reveals that she strategically fabricated and excluded information in order to create a specific memory of the past in the minds of southerners. Rutherford had difficulty discerning whether or not the economic benefits of industrialization outweighed the accompanying social consequences. Yet, she used the power of text in an attempt to recreate the Old South social structure based on a racial hierarchy that was bound to be defeated by the rising tide of indu-strialization

A seismically induced onshore surge deposit at the KPg boundary, North Dakota

The most immediate effects of the terminal-Cretaceous Chicxulub impact, essential to understanding the global-scale environmental and biotic collapses that mark the Cretaceous–Paleogene extinction, are poorly resolved despite extensive previous work. Here, we help to resolve this by describing a rapidly emplaced, high-energy onshore surge deposit from the terrestrial Hell Creek Formation in Montana. Associated ejecta and a cap of iridium-rich impactite reveal that its emplacement coincided with the Chicxulub event. Acipenseriform fish, densely packed in the deposit, contain ejecta spherules in their gills and were buried by an inland-directed surge that inundated a deeply incised river channel before accretion of the fine-grained impactite. Although this deposit displays all of the physical characteristics of a tsunami runup, the timing (\u3c1 hour postimpact) is instead consistent with the arrival of strong seismic waves from the magnitude Mw ∼10 to 11 earthquake generated by the Chicxulub impact, identifying a seismically coupled seiche inundation as the likely cause. Our findings present high-resolution chronology of the immediate aftereffects of the Chicxulub impact event in the Western Interior, and report an impact-triggered onshore mix of marine and terrestrial sedimentation—potentially a significant advancement for eventually resolving both the complex dynamics of debris ejection and the full nature and extent of biotic disruptions that took place in the first moments postimpact

GEOLOGY, TAPHONOMY, AND PALEOECOLOGY OF A UNIQUE UPPER CRETACEOUS BONEBED NEAR THE CRETACEOUS-TERTIARY BOUNDARY IN SOUTH DAKOTA

This research examines a Konzentrat-Lagerstätte, the Bone Butte site, in the Upper Cretaceous Hell Creek Formation of South Dakota. Field data from a diverse multispecific bonebed in Harding County, South Dakota, including sedimentologic, stratigraphic, taphonomic, floral, and faunal observations, are used to reconstruct the depositional history, depositional environment, and paleoecology of the site, while comparing it to other sites within the Hell Creek Formation. Taphonomic analyses of bone completeness, abrasion, and sorting reveal the presence of autochthonous and allochthonous faunas, and demonstrate the heterogeneity of the Hell Creek dinosaurian fauna. Particularly noteworthy components of the Bone Butte ecology are undescribed insect and ornithurine bird faunas. Also, a rare instance of dinosaur predation is evidenced by theropod tooth marks and an embedded tooth found in two fused proximal hadrosaur vertebrae. The precise temporal resolution of the site, less than 7 years as indicated by sedimentologic, paleobotanical, and vertebrate ontogenetic data, provides the basis of a reconstruction of the local climate and ecology. Finely preserved clay-pebble laminae show evidence of annual rainfall magnitude, and pyrofusain-enriched laminae may indicate a chronology of significant local forest fires. The optimum temperature requirements for plants at Bone Butte, for example the gymnosperm Taxodium, give a rough estimation of annual temperature variation. Thousands of collected vertebrate specimens provide a means of tracking ontogenetic ratios from hatchlings to adulthood in the local stratigraphic column. In some of the dinosaur specimens, the presence of medullary bone allowed estimation of their seasonal nesting habits. Laboratory experiments and examination of modern fluvial analogs augmented the analysis of data from the Bone Butte site. A reconstruction of the Bone Butte river system and site-forming events are presented in this work. In particular, the presence of marine organisms at Bone Butte indicates the river system's close proximity to the paleoshoreline

Detecting and Characterizing Young Quasars. III. the Impact of Gravitational Lensing Magnification

We test the impact of gravitational lensing on the lifetime estimates of seven high-redshift quasars at redshift z 3 6. The targeted quasars are identified by their small observed proximity zone sizes, which indicate extremely short quasar lifetimes (t Q 2 105yr). However, these estimates of quasar lifetimes rely on the assumption that the observed luminosities of the quasars are intrinsic and not magnified by gravitational lensing, which would bias the lifetime estimates toward younger ages. In order to test the possible effects of gravitational lensing, we obtain high-resolution images of the seven quasars with the Hubble Space Telescope and look for signs of strong lensing. We do not find any evidence of strong lensing, i.e., all quasars are well described by point sources, and no foreground lensing galaxy is detected. We estimate that the strong-lensing probabilities for these quasars are extremely small ( 1/41.4 × 10-5) and show that weak lensing changes the estimated quasar lifetimes by only 20.2 dex. We thus confirm that the short lifetimes of these quasars are intrinsic. The existence of young quasars indicates a high obscured fraction, radiatively inefficient accretion, and/or flickering lightcurves for high-redshift quasars. We further discuss the impact of lensing magnification on measurements of black hole masses and Eddington ratios of quasars

A seismically induced onshore surge deposit at the KPg boundary, North Dakota

This work is licensed under a Creative Commons Attribution 4.0 International License.The most immediate effects of the terminal-Cretaceous Chicxulub impact, essential to understanding the global-scale environmental and biotic collapses that mark the Cretaceous–Paleogene extinction, are poorly resolved despite extensive previous work. Here, we help to resolve this by describing a rapidly emplaced, high-energy onshore surge deposit from the terrestrial Hell Creek Formation in Montana. Associated ejecta and a cap of iridium-rich impactite reveal that its emplacement coincided with the Chicxulub event. Acipenseriform fish, densely packed in the deposit, contain ejecta spherules in their gills and were buried by an inland-directed surge that inundated a deeply incised river channel before accretion of the fine-grained impactite. Although this deposit displays all of the physical characteristics of a tsunami runup, the timing (<1 hour postimpact) is instead consistent with the arrival of strong seismic waves from the magnitude Mw ∼10 to 11 earthquake generated by the Chicxulub impact, identifying a seismically coupled seiche inundation as the likely cause. Our findings present high-resolution chronology of the immediate aftereffects of the Chicxulub impact event in the Western Interior, and report an impact-triggered onshore mix of marine and terrestrial sedimentation—potentially a significant advancement for eventually resolving both the complex dynamics of debris ejection and the full nature and extent of biotic disruptions that took place in the first moments postimpact.Netherlands Organization for Scientific Research Grant 864.12.005United Kingdom Science and Technology Facilities Council (Grant STFC:ST/M001814/1

National Athletic Trainers\u27 Association Position Statement: Safe Weight Loss and Maintenance Practices in Sport and Exercise

Objective: To present athletic trainers with recommendations for safe weight loss and weight maintenance practices for athletes and active clients and to provide athletes, clients, coaches, and parents with safe guidelines that will allow athletes and clients to achieve and maintain weight and body composition goals. Background: Unsafe weight management practices can compromise athletic performance and negatively affect health. Athletes and clients often attempt to lose weight by not eating, limiting caloric or specific nutrients from the diet, engaging in pathogenic weight control behaviors, and restricting fluids. These people often respond to pressures of the sport or activity, coaches, peers, or parents by adopting negative body images and unsafe practices to maintain an ideal body composition for the activity. We provide athletic trainers with recommendations for safe weight loss and weight maintenance in sport and exercise. Although safe weight gain is also a concern for athletic trainers and their athletes and clients, that topic is outside the scope of this position statement. Recommendations: Athletic trainers are often the source of nutrition information for athletes and clients; therefore, they practices, and methods to change body composition. Body composition assessments should be done in the most scientifically appropriate manner possible. Reasonable and individualized weight and body composition goals should be identified by appropriately trained health care personnel (eg, athletic trainers, registered dietitians, physicians). In keeping with the American Dietetics Association (ADA) preferred nomenclature, this document uses the terms registered dietitian or dietician when referring to a food and nutrition expert who has met the academic and professional requirements specified by the ADA\u27s Commission on Accreditation for Dietetics Education. In some cases, a registered nutritionist may have equivalent credentials and be the commonly used term. All weight management and exercise protocols used to achieve these goals should be safe and based on the most current evidence. Athletes, clients, parents, and coaches should be educated on how to determine safe weight and body composition so that athletes and clients more safely achieve competitive weights that will meet sport and activity requirements while also allowing them to meet their energy and nutritional needs for optimal health and performance

EM-mosaic detects mosaic point mutations that contribute to congenital heart disease.

BackgroundThe contribution of somatic mosaicism, or genetic mutations arising after oocyte fertilization, to congenital heart disease (CHD) is not well understood. Further, the relationship between mosaicism in blood and cardiovascular tissue has not been determined.MethodsWe developed a new computational method, EM-mosaic (Expectation-Maximization-based detection of mosaicism), to analyze mosaicism in exome sequences derived primarily from blood DNA of 2530 CHD proband-parent trios. To optimize this method, we measured mosaic detection power as a function of sequencing depth. In parallel, we analyzed our cohort using MosaicHunter, a Bayesian genotyping algorithm-based mosaic detection tool, and compared the two methods. The accuracy of these mosaic variant detection algorithms was assessed using an independent resequencing method. We then applied both methods to detect mosaicism in cardiac tissue-derived exome sequences of 66 participants for which matched blood and heart tissue was available.ResultsEM-mosaic detected 326 mosaic mutations in blood and/or cardiac tissue DNA. Of the 309 detected in blood DNA, 85/97 (88%) tested were independently confirmed, while 7/17 (41%) candidates of 17 detected in cardiac tissue were confirmed. MosaicHunter detected an additional 64 mosaics, of which 23/46 (50%) among 58 candidates from blood and 4/6 (67%) of 6 candidates from cardiac tissue confirmed. Twenty-five mosaic variants altered CHD-risk genes, affecting 1% of our cohort. Of these 25, 22/22 candidates tested were confirmed. Variants predicted as damaging had higher variant allele fraction than benign variants, suggesting a role in CHD. The estimated true frequency of mosaic variants above 10% mosaicism was 0.14/person in blood and 0.21/person in cardiac tissue. Analysis of 66 individuals with matched cardiac tissue available revealed both tissue-specific and shared mosaicism, with shared mosaics generally having higher allele fraction.ConclusionsWe estimate that ~ 1% of CHD probands have a mosaic variant detectable in blood that could contribute to cardiac malformations, particularly those damaging variants with relatively higher allele fraction. Although blood is a readily available DNA source, cardiac tissues analyzed contributed ~ 5% of somatic mosaic variants identified, indicating the value of tissue mosaicism analyses

Detecting and Characterizing Young Quasars. III. The Impact of Gravitational Lensing Magnification

We test the impact of gravitational lensing on the lifetime estimates of seven high-redshift quasars at redshift $z\gtrsim6$. The targeted quasars are identified by their small observed proximity zone sizes, which indicate extremely short quasar lifetimes $(t_Q\lesssim10^5 \text{ yrs})$. However, these estimates of quasar lifetimes rely on the assumption that the observed luminosities of the quasars are intrinsic and not magnified by gravitational lensing, which would bias the lifetime estimates towards younger ages. In order to test possible effects of gravitational lensing, we obtain high-resolution images of the seven quasars with the {\em Hubble Space Telescope (HST)} and look for signs of strong lensing. We do not find any evidence of strong lensing, i.e., all quasars are well-described by point sources, and no foreground lensing galaxy is detected. We estimate that the strong lensing probabilities for these quasars are extremely small $(\sim1.4\times10^{-5})$, and show that weak lensing changes the estimated quasar lifetimes by only $\lesssim0.2$ dex. We thus confirm that the short lifetimes of these quasars are intrinsic. The existence of young quasars indicates a high obscured fraction, radiatively inefficient accretion, and/or flickering light curves for high-redshift quasars. We further discuss the impact of lensing magnification on measurements of black hole masses and Eddington ratios of quasars.Comment: 14 pages, 4 figures, 3 tables. Accepted by the Astrophysical Journa