First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment.

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9 GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36 GeV/c^{2}, rejecting cross sections above 9.2×10^{-48} cm at the 90% confidence level.

Unhealthy Food and Beverage Consumption in Children and Risk of Overweight and Obesity: A Systematic Review and Meta-Analysis.

This WHO-commissioned review contributed to the update of complementary feeding recommendations, synthesizing evidence on effects of unhealthy food and beverage consumption in children on overweight and obesity. We searched PubMed (Medline), Cochrane CENTRAL, and Embase for articles, irrespective of language or geography. Inclusion criteria were: 1) randomized controlled trials (RCTs), non-RCTs, cohort studies, and pre/post studies with control; 2) participants aged ≤10.9 y at exposure; 3) studies reporting greater consumption of unhealthy foods/beverages compared with no or low consumption; 4) studies assessing anthropometric and/or body composition; and 5) publication date ≥1971. Unhealthy foods and beverages were defined using nutrient- and food-based approaches. Risk of bias was assessed using the ROBINS-I (risk of bias in nonrandomized studies of interventions version I) and RoB2 [Cochrane RoB (version 2)] tools for nonrandomized and randomized studies, respectively. Narrative synthesis was complemented by meta-analyses where appropriate. Certainty of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. Of 26,542 identified citations, 60 studies from 71 articles were included. Most studies were observational (59/60), and no included studies were from low-income countries. The evidence base was low quality, as assessed by ROBINS-I and RoB2 tools. Evidence synthesis was limited by the different interventions and comparators across studies. Evidence indicated that consumption of sugar-sweetened beverages (SSBs) and unhealthy foods in childhood may increase BMI/BMI z-score, percentage body fat, or odds of overweight/obesity (low certainty of evidence). Artificially sweetened beverages and 100% fruit juice consumption make little/no difference to BMI, percentage body fat, or overweight/obesity outcomes (low certainty of evidence). Meta-analyses of a subset of studies indicated a positive association between SSB intake and percentage body fat, but no association with change in BMI and BMI z-score. High-quality epidemiological studies that are designed to assess the effects of unhealthy food consumption during childhood on risk of overweight/obesity are needed to contribute to a more robust evidence base upon which to design policy recommendations. This protocol was registered at https://www.crd.york.ac.uk/PROSPERO as CRD42020218109.

Results of a Search for Sub-GeV Dark Matter Using 2013 LUX Data.

The scattering of dark matter (DM) particles with sub-GeV masses off nuclei is difficult to detect using liquid xenon-based DM search instruments because the energy transfer during nuclear recoils is smaller than the typical detector threshold. However, the tree-level DM-nucleus scattering diagram can be accompanied by simultaneous emission of a bremsstrahlung photon or a so-called "Migdal" electron. These provide an electron recoil component to the experimental signature at higher energies than the corresponding nuclear recoil. The presence of this signature allows liquid xenon detectors to use both the scintillation and the ionization signals in the analysis where the nuclear recoil signal would not be otherwise visible. We report constraints on spin-independent DM-nucleon scattering for DM particles with masses of 0.4-5 GeV/c^{2} using 1.4×10^{4} kg day of search exposure from the 2013 data from the Large Underground Xenon (LUX) experiment for four different classes of mediators. This analysis extends the reach of liquid xenon-based DM search instruments to lower DM masses than has been achieved previously.

Spinal endothelin content is elevated after moderate local trauma in the rat to levels associated with locomotor dysfunction after intrathecal injection.

The role of endothelin (ET) in the pathophysiology of secondary neural damage after experimental spinal cord injury (SCI) was examined in a rat model of weight-drop contusion injury. Initial studies demonstrated a significant increase in spinal ET concentrations in a 7.5-mm segment of tissue (centered at the impact site) at 30 min, 4 h, and 24 h after a moderate (50 g-cm) contusion injury. Subsequent experiments were aimed at reproducing these elevations by the intrathecal (i.t.) administration of ET and observing the effect on locomotor function. These studies showed that i.t. dosage of 9.6 ng produced spinal cord elevations of ET similar to those seen 30 min after moderate SCI as well as mild locomotor deficits. A 48 ng dose of ET resulted in moderate to severe locomotor deficits that were associated with spinal ET elevations much greater than those seen after injury. The mild deficits attributable to the lower dose of ET could contribute to the pathophysiological actions of other purported secondary injury mediators. The more pronounced locomotor deficits associated with the higher dose could be of relevance for severe SCI.

The elusive cure: health care reform.

Everyone seems to believe Americans are entitled to the best health care, regardless of cost. But how to curb soaring health expenses and provide care to the 37 million uninsured in our country is a perplexing problem, one that policy makers and providers are trying to solve with a wide variety of health reform proposals.

Mediterranean action plan: an interim evaluation.

The Mediterranean Action Plan is an extensive program of regional environmental cooperation on technical and institutional approaches to pollution monitoring, environmental assessment, and policy-making. The simultaneous development of a regional monitoring network and legal instruments to protect the Mediterranean from pollution is an important achievement, which provides a firm basis for continuing cooperative efforts.