One strategy for increasing physical activity is to create and enhance access to park space. We assessed the literature on the relationship of parks and objectively measured physical activity in ...population-based studies in the United States (US) and identified limitations in current built environment and physical activity measurement and reporting. Five English-language scholarly databases were queried using standardized search terms. Abstracts were screened for the following inclusion criteria: 1) published between January 1990 and June 2013; 2) US-based with a sample size greater than 100 individuals; 3) included built environment measures related to parks or trails; and 4) included objectively measured physical activity as an outcome. Following initial screening for inclusion by two independent raters, articles were abstracted into a database. Of 10,949 abstracts screened, 20 articles met the inclusion criteria. Five articles reported a significant positive association between parks and physical activity. Nine studies found no association, and six studies had mixed findings. Our review found that even among studies with objectively measured physical activity, the association between access to parks and physical activity varied between studies, possibly due to heterogeneity of exposure measurement. Self-reported (vs. independently-measured) neighborhood park environment characteristics and smaller (vs. larger) buffer sizes were more predictive of physical activity. We recommend strategies for further research, employing standardized reporting and innovative study designs to better understand the relationship of parks and physical activity.
•We reviewed research on parks and objectively measured physical activity.•Measurement and reporting of park density and proximity is not standardized.•The association of parks and physical activity was inconsistent across studies.•Standardized measurement and reporting are needed for future meta-analyses.
Genetic diversity loss in the Anthropocene Exposito-Alonso, Moises; Booker, Tom R; Czech, Lucas ...
Science (American Association for the Advancement of Science),
09/2022, Letnik:
377, Številka:
6613
Journal Article
Recenzirano
Odprti dostop
Anthropogenic habitat loss and climate change are reducing species' geographic ranges, increasing extinction risk and losses of species' genetic diversity. Although preserving genetic diversity is ...key to maintaining species' adaptability, we lack predictive tools and global estimates of genetic diversity loss across ecosystems. We introduce a mathematical framework that bridges biodiversity theory and population genetics to understand the loss of naturally occurring DNA mutations with decreasing habitat. By analyzing genomic variation of 10,095 georeferenced individuals from 20 plant and animal species, we show that genome-wide diversity follows a mutations-area relationship power law with geographic area, which can predict genetic diversity loss from local population extinctions. We estimate that more than 10% of genetic diversity may already be lost for many threatened and nonthreatened species, surpassing the United Nations' post-2020 targets for genetic preservation.
Galactic outflows of molecular gas are a common occurrence in galaxies and may represent a mechanism by which galaxies self-regulate their growth, redistributing gas that could otherwise have formed ...stars. We previously presented the first survey of molecular outflows at z > 4 toward a sample of massive, dusty galaxies. Here we characterize the physical properties of the molecular outflows discovered in our survey. Using low-redshift outflows as a training set, we find agreement at the factor of 2 level between several outflow rate estimates. We find molecular outflow rates of 150-800 yr−1 and infer mass loading factors just below unity. Among the high-redshift sources, the molecular mass loading factor shows no strong correlations with any other measured quantity. The outflow energetics are consistent with expectations for momentum-driven winds with star formation as the driving source, with no need for energy-conserving phases. There is no evidence for active galactic nucleus activity in our sample, and while we cannot rule out deeply buried active galactic nuclei, their presence is not required to explain the outflow energetics, in contrast to nearby obscured galaxies with fast outflows. The fraction of the outflowing gas that will escape into the circumgalactic medium (CGM), though highly uncertain, may be as high as 50%. This nevertheless constitutes only a small fraction of the total cool CGM mass based on a comparison to z ∼ 2-3 quasar absorption line studies, but could represent 10% of the CGM metal mass. Our survey offers the first statistical characterization of molecular outflow properties in the very early universe.
The rapid spread of the highly contagious Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) along with its high number of mutations in the spike gene has raised alarms ...about the effectiveness of current medical countermeasures. To address this concern, we measured the neutralization of the Omicron BA.1 variant pseudovirus by postvaccination serum samples after two and three immunizations with the Pfizer/BioNTech162b2 SARS-CoV-2 mRNA (Pfizer/BNT162b2) vaccine, convalescent serum samples from unvaccinated individuals infected by different variants, and clinical-stage therapeutic antibodies. We found that titers against the Omicron variant were low or undetectable after two immunizations and in many convalescent serum samples, regardless of the infecting variant. A booster vaccination increased titers more than 30-fold against Omicron to values comparable to those seen against the D614G variant after two immunizations. Neither age nor sex was associated with the differences in postvaccination antibody responses. We also evaluated 18 clinical-stage therapeutic antibody products and an antibody mimetic protein product obtained directly from the manufacturers. Five monoclonal antibodies, the antibody mimetic protein, three antibody cocktails, and two polyclonal antibody preparations retained measurable neutralization activity against Omicron with a varying degree of potency. Of these, only three retained potencies comparable to the D614G variant. Two therapeutic antibody cocktails in the tested panel that are authorized for emergency use in the United States did not neutralize Omicron. These findings underscore the potential benefit of mRNA vaccine boosters for protection against Omicron and the need for rapid development of antibody therapeutics that maintain potency against emerging variants.
ABSTRACT
We present an extensive ALMA spectroscopic follow-up programme of the $z\, {=}\, 4.3$ structure SPT2349–56, one of the most actively star-forming protocluster cores known, to identify ...additional members using their C ii 158 μm and CO(4–3) lines. In addition to robustly detecting the 14 previously published galaxies in this structure, we identify a further 15 associated galaxies at $z\, {=}\, 4.3$, resolving 55$\, {\pm }\,$5 per cent of the 870 μm flux density at 0.5 arcsec resolution compared to 21 arcsec single-dish data. These galaxies are distributed into a central core containing 23 galaxies extending out to 300 kpc in diameter, and a northern extension, offset from the core by 400 kpc, containing three galaxies. We discovered three additional galaxies in a red Herschel-SPIRE source 1.5 Mpc from the main structure, suggesting the existence of many other sources at the same redshift as SPT2349–56 that are not yet detected in the limited coverage of our data. An analysis of the velocity distribution of the central galaxies indicates that this region may be virialized with a mass of (9$\pm 5)\, {\times }\, 10^{12}$ M⊙, while the two offset galaxy groups are about 30 and 60 per cent less massive and show significant velocity offsets from the central group. We calculate the C ii and far-infrared number counts, and find evidence for a break in the C ii luminosity function. We estimate the average SFR density within the region of SPT2349–56 containing single-dish emission (a proper diameter of 720 kpc), assuming spherical symmetry, to be roughly 4$\, {\times }\, 10^4$ M⊙ yr−1 Mpc−3; this may be an order of magnitude greater than the most extreme examples seen in simulations.
Abstract
Two cases of dryline convection initiation (CI) over north Texas have been simulated (3 April 2012 and 15 May 2013) from a 50-member WRF-DART ensemble adjustment Kalman filter (EAKF) ...ensemble. In this study, ensemble sensitivity analysis (ESA) is applied to a convective forecast metric, maximum composite reflectivity (referred to as the response function), as a simple proxy for CI to analyze dynamic mesoscale sensitivities at the surface and aloft. Analysis reveals positional and magnitude sensitivities related to the strength and placement of important dynamic features. Convection initiation is sensitive to the evolving temperature and dewpoint fields upstream of the forecast response region in the near-CI time frame (0–12 h), prior to initiation. The sensitivity to thermodynamics is also manifest in the magnitude of dewpoint gradients along the dryline that triggers the convection. ESA additionally highlights the importance of antecedent precipitation and cold pool generation that modifies the pre-CI environment. Aloft, sensitivity of CI to a weak short-wave trough and capping inversion-level temperature is coherent, consistent, and traceable through the entire forecast period. Notwithstanding the (often) non-Gaussian distribution of ensemble member forecasts of convection, which violate the underpinnings of ESA theory, ESA is demonstrated to sufficiently identify regions that influence dryline CI. These results indicate an application of ESA for severe storm forecasting at operational centers and forecast offices as well as other mesoscale forecasting applications.
The development of methods to achieve efficient reprogramming of human cells while avoiding the permanent presence of reprogramming transgenes represents a critical step toward the use of induced ...pluripotent stem cells (iPSC) for clinical purposes, such as disease modeling or reconstituting therapies. Although several methods exist for generating iPSC free of reprogramming transgenes from mouse cells or neonatal normal human tissues, a sufficiently efficient reprogramming system is still needed to achieve the widespread derivation of disease‐specific iPSC from humans with inherited or degenerative diseases. Here, we report the use of a humanized version of a single lentiviral “stem cell cassette” vector to accomplish efficient reprogramming of normal or diseased skin fibroblasts obtained from humans of virtually any age. Simultaneous transfer of either three or four reprogramming factors into human target cells using this single vector allows derivation of human iPSC containing a single excisable viral integration that on removal generates human iPSC free of integrated transgenes. As a proof of principle, here we apply this strategy to generate >100 lung disease‐specific iPSC lines from individuals with a variety of diseases affecting the epithelial, endothelial, or interstitial compartments of the lung, including cystic fibrosis, α‐1 antitrypsin deficiency‐related emphysema, scleroderma, and sickle‐cell disease. Moreover, we demonstrate that human iPSC generated with this approach have the ability to robustly differentiate into definitive endoderm in vitro, the developmental precursor tissue of lung epithelia. STEM CELLS 2010;28:1728–1740
In the inertial limit, the resonance frequency of the quartz crystal microbalance (QCM) is related to the coupled mass on the quartz sensor through the Sauerbrey expression that relates the mass to ...the change in resonance frequency. However, when the thickness of the film is sufficiently large, the relationship becomes more complicated and both the frequency and damping of the crystal resonance must be considered. In this regime, a rheological model of the material must be used to accurately extract the adhered film’s thickness, shear modulus, and viscoelastic phase angle from the data. In the present work we examine the suitability of two viscoelastic models, a simple Voigt model (Physica Scripta 1999, 59, 391–396) and a more realistic power-law model (Langmuir 2015, 31, 4008−4017), to extract the rheological properties of a thermoresponsive hydrogel film. By changing temperature and initial dry film thickness of the gel, the operation of QCM was traversed from the Sauerbrey limit, where viscous losses do not impact the frequency, through the regime where the QCM response is sensitive to viscoelastic properties. The density-shear modulus and the viscoelastic phase angle from the two models are in good agreement when the shear wavelength ratio, d/λ n , is in the range of 0.05–0.20, where d is the film thickness and λ n is the wavelength of the mechanical shear wave at the n th harmonic. We further provide a framework for estimating the physical properties of soft materials in the megahertz regime by using the physical behavior of polyelectrolyte complexes. This provides the user with an approximate range of allowable film thicknesses for accurate viscoelastic analysis with either model, thus enabling better use of the QCM-D in soft materials research.
Aims. We present and study spatially resolved imaging obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) of multiple 12CO(J = 6 − 5, 8−7, and 9−8) and two H2O(202−111 and 211−202) ...emission lines and cold dust continuum toward the gravitationally lensed dusty star-forming galaxy SPT 0346-52 at z = 5.656. Methods. Using a visibility-domain source-plane reconstruction we probe the structure and dynamics of the different components of the interstellar medium (ISM) in this galaxy down to scales of 1 kpc in the source plane. Results. Measurements of the intrinsic sizes of the different CO emission lines indicate that the higher J transitions trace more compact regions in the galaxy. Similarly, we find smaller dust continuum intrinsic sizes with decreasing wavelength, based on observations at rest frame 130, 300, and 450 μm. The source shows significant velocity structure, and clear asymmetry where an elongated structure is observed in the source plane with significant variations in their reconstructed sizes. This could be attributed to a compact merger or turbulent disk rotation. The differences in velocity structure through the different line tracers, however, hint at the former scenario in agreement with previous CII line imaging results. Measurements of the CO line ratios and magnifications yield significant variations as a function of velocity, suggesting that modeling of the ISM using integrated values could be misinterpreted. Modeling of the ISM in SPT 0346-52 based on delensed fluxes indicates a highly dense and warm medium, qualitatively similar to that observed in high-redshift quasar hosts.
Massive galaxy-scale outflows of gas are one of the most commonly invoked mechanisms to regulate the growth and evolution of galaxies throughout the universe. While the gas in outflows spans a large ...range of temperatures and densities, the cold molecular phase is of particular interest because molecular outflows may be capable of suppressing star formation in galaxies by removing the star-forming gas. We have conducted the first survey of molecular outflows at z > 4, targeting 11 strongly lensed dusty, star-forming galaxies (DSFGs) with high-resolution Atacama Large Millimeter/submillimeter Array observations of OH 119 m absorption as an outflow tracer. In this first paper, we give an overview of the survey, focusing on the detection rate and structure of molecular outflows. We find unambiguous evidence for outflows in 8/11 galaxies (73%), more than tripling the number known at z > 4. This implies that molecular winds in z > 4 DSFGs must have both a near-unity occurrence rate and large opening angles to be detectable in absorption. Lensing reconstructions reveal that 500 pc scale clumpy structures in the outflows are common. The individual clumps are not directly resolved, but from optical depth arguments we expect that future observations will require 50-200 pc spatial resolution to resolve them. We do not detect high-velocity C ii wings in any of the sources with clear OH outflows, indicating that C ii is not a reliable tracer of molecular outflows. Our results represent a first step toward characterizing molecular outflows at z > 4 at the population level, demonstrating that large-scale outflows are ubiquitous among early massive, dusty galaxies.
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