100 ancient genomes show repeated population turnovers in Neolithic Denmark.

Major migration events in Holocene Eurasia have been characterized genetically at broad regional scales. However, insights into the population dynamics in the contact zones are hampered by a lack of ancient genomic data sampled at high spatiotemporal resolution. Here, to address this, we analysed shotgun-sequenced genomes from 100 skeletons spanning 7,300 years of the Mesolithic period, Neolithic period and Early Bronze Age in Denmark and integrated these with proxies for diet (C and N content), mobility (Sr/Sr ratio) and vegetation cover (pollen).

Exploring fingerprints of ultrafast structural dynamics in molecular solutions with an X-ray laser.

We apply ultrashort X-ray laser pulses to track optically excited structural dynamics of [Ir(dimen)] molecules in solution. In our exploratory study we determine angular correlations in the scattered X-rays, which comprise a complex fingerprint of the ultrafast dynamics. Model-assisted analysis of the experimental correlation data allows us to elucidate various aspects of the photoinduced changes in the excited molecular ensembles.

Tracking structural solvent reorganization and recombination dynamics following e photoabstraction from aqueous I with femtosecond x-ray spectroscopy and scattering.

We present a sub-picosecond resolved investigation of the structural solvent reorganization and geminate recombination dynamics following 400 nm two-photon excitation and photodetachment of a valence p electron from the aqueous atomic solute, I(aq). The measurements utilized time-resolved X-ray Absorption Near Edge Structure (TR-XANES) spectroscopy and X-ray Solution Scattering (TR-XSS) at the Linac Coherent Light Source x-ray free electron laser in a laser pump/x-ray probe experiment. The XANES measurements around the L-edge of the generated nascent iodine atoms (I) yield an average electron ejection distance from the iodine parent of 7.

A 2-million-year-old ecosystem in Greenland uncovered by environmental DNA.

Late Pliocene and Early Pleistocene epochs 3.6 to 0.8 million years ago had climates resembling those forecasted under future warming.

Extensive inland thinning and speed-up of Northeast Greenland Ice Stream.

Over the past two decades, ice loss from the Greenland ice sheet (GrIS) has increased owing to enhanced surface melting and ice discharge to the ocean. Whether continuing increased ice loss will accelerate further, and by how much, remains contentious. A main contributor to future ice loss is the Northeast Greenland Ice Stream (NEGIS), Greenland's largest basin and a prominent feature of fast-flowing ice that reaches the interior of the GrIS.

Hypothesis: Metformin is a potential reproductive toxicant.

Metformin is the first-line oral treatment for type 2 diabetes mellitus and is prescribed to more than 150 million people worldwide. Metformin's effect as a glucose-lowering drug is well documented but the precise mechanism of action is unknown. A recent finding of an association between paternal metformin treatment and increased numbers of genital birth defects in sons and a tendency towards a skewed secondary sex ratio with less male offspring prompted us to focus on other evidence of reproductive side effects of this drug.

Overuse of medical care in paediatrics: A survey from five countries in the European Academy of Pediatrics.

Unlabelled: Studies and initiatives such as the "Choosing wisely" (CW) campaign emphasise evidence-based investigations and treatment to avoid overdiagnosis and overtreatment. The perception of the extent of medical overactivity among professionals and drivers behind are not well studied in the paediatric field.

Aim: We aimed to investigate the physicians' opinion and clarify the main drivers regarding medical overactivity in member countries of the European Academy of Paediatrics (EAP).

Optically Induced Anisotropy in Time-Resolved Scattering: Imaging Molecular-Scale Structure and Dynamics in Disordered Media with Experiment and Theory.

Time-resolved scattering experiments enable imaging of materials at the molecular scale with femtosecond time resolution. However, in disordered media they provide access to just one radial dimension thus limiting the study of orientational structure and dynamics. Here we introduce a rigorous and practical theoretical framework for predicting and interpreting experiments combining optically induced anisotropy and time-resolved scattering.

Comparative performance of obstetric comorbidity indices within categories of race and ethnicity: an external validation study.

Background: Existing obstetric comorbidity adjustment indices were created without explicitly accounting for sociodemographic diversity in the development populations, which could lead to imprecise estimates if these indices are applied to populations different from the ones in which they were developed. The objective of this study was to validate two obstetric comorbidity indices (one using severe maternal morbidity [SMM] and one using end-organ injury or mortality) within categories of race/ethnicity.

Methods: Delivery hospitalizations from the State Inpatient Databases for Florida, Maryland, Kentucky, Washington (2015-2018) and New York (2015-2016) were analyzed.

Winter warming stimulates vegetative growth and alters fruit quality of blackcurrant (Ribes nigrum).

The rate of global warming varies in magnitude between seasons, with warming being more pronounced in winter and spring than in summer and autumn at high latitudes. Winter warming can have profound effects on dormancy release and spring phenology of perennial fruit crops, but potential follow-on impacts on growth, fruit yield or quality have only rarely been investigated. We studied the effects of mild winter warming on spring phenology, current year shoot growth, cropping performance and fruit quality in four field-grown cultivars of blackcurrant with different chilling requirements.

A Late Paleocene age for Greenland's Hiawatha impact structure.

The ~31-km-wide Hiawatha structure, located beneath Hiawatha Glacier in northwestern Greenland, has been proposed as an impact structure that may have formed after the Pleistocene inception of the Greenland Ice Sheet. To date the structure, we conducted Ar/Ar analyses on glaciofluvial sand and U-Pb analyses on zircon separated from glaciofluvial pebbles of impact melt rock, all sampled immediately downstream of Hiawatha Glacier. Unshocked zircon in the impact melt rocks dates to ~1915 million years (Ma), consistent with felsic intrusions found in local bedrock.

Association of Physician Management Companies and Private Equity Investment With Commercial Health Care Prices Paid to Anesthesia Practitioners.

Importance: Physician management companies (PMCs), often backed by private equity (PE), are increasingly providing staffing and management services to health care facilities, yet little is known of their influence on prices.

Objective: To study changes in prices paid to practitioners (anesthesiologists and certified registered nurse anesthetists) before and after an outpatient facility contracted with a PMC.

Design, Setting, And Participants: This retrospective cohort study used difference-in-differences methods to compare price changes before and after a facility contracted with a PMC with facilities that did not and to compare differences between PMCs with and without PE investment.

Femtosecond X-ray Spectroscopy Directly Quantifies Transient Excited-State Mixed Valency.

Quantifying charge delocalization associated with short-lived photoexcited states of molecular complexes in solution remains experimentally challenging, requiring local element specific femtosecond experimental probes of time-evolving electron transfer. In this study, we quantify the evolving valence hole charge distribution in the photoexcited charge transfer state of a prototypical mixed valence bimetallic iron-ruthenium complex, [(CN)FeCNRu(NH)], in water by combining femtosecond X-ray spectroscopy measurements with time-dependent density functional theory calculations of the excited-state dynamics. We estimate the valence hole charge that accumulated at the Fe atom to be 0.

Quality Assurance and Quality Improvement in the Labor and Delivery Setting.

Quality assurance (QA) is the maintenance of a desired level of quality, whereas quality improvement (QI) is the continuous process of creating systems to make things better. Implementation science promotes the systematic uptake of best practices. Bundles are a structured list of best practices whereas toolkits provide the necessary details, rationale, and implementation materials, such as sample policies and protocols.

Late Quaternary dynamics of Arctic biota from ancient environmental genomics.

During the last glacial-interglacial cycle, Arctic biotas experienced substantial climatic changes, yet the nature, extent and rate of their responses are not fully understood. Here we report a large-scale environmental DNA metagenomic study of ancient plant and mammal communities, analysing 535 permafrost and lake sediment samples from across the Arctic spanning the past 50,000 years. Furthermore, we present 1,541 contemporary plant genome assemblies that were generated as reference sequences.

Association of Surprise-Billing Legislation with Prices Paid to In-Network and Out-of-Network Anesthesiologists in California, Florida, and New York: An Economic Analysis.

Importance: Several states have passed surprise-billing legislation to protect patients from unanticipated out-of-network medical bills, yet little is known about how state laws influence out-of-network prices and whether spillovers exist to in-network prices.

Objective: To identify any changes in prices paid to out-of-network anesthesiologists at in-network facilities and to in-network anesthesiologists before and after states passed surprise-billing legislation.

Design, Setting, And Participants: This retrospective economic analysis used difference-in-differences methods to compare price changes before and after the passage of legislation in California, Florida, and New York, which passed comprehensive surprise-billing legislation between January 1, 2014, and December 31, 2017, to 45 states that did not.

Patient-Reported Pain and Opioid Use After Ambulatory Head and Neck Surgery.

Objective: The main objective of this study was to quantify daily pain and opioid use in patients after hemithyroidectomy and cervical lymph node biopsy (CLNB). The secondary objective was to identify factors associated with decreased pain and opioid use.

Study Design: Prospective cohort study from June 2017 to February 2019.