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Susceptibility to infection such as SARS-CoV-2 may be influenced by host genotype. TwinsUK volunteers (n = 3261) completing the C-19 COVID-19 symptom tracker app allowed classical twin studies of COVID-19 symptoms, including predicted COVID-19, a symptom-based algorithm to predict true infection, derived from app users tested for SARS-CoV-2. We found heritability of 49% (32−64%) for delirium; 34% (20−47%) for diarrhea; 31% (8−52%) for fatigue; 19% (0−38%) for anosmia; 46% (31−60%) for skipped meals and 31% (11−48%) for predicted COVID-19. Heritability estimates were not affected by cohabiting or by social deprivation. The results suggest the importance of host genetics in the risk of clinical manifestations of COVID-19 and provide grounds for planning genome-wide association studies to establish specific genes involved in viral infectivity and the host immune response.
This study provides a morphological and phylogenetic characterization of two novel species of the order Haplosporida (Haplosporidium carcini n. sp., and H. cranc n. sp.) infecting the common shore crab Carcinus maenas collected at one location in Swansea Bay, South Wales, UK. Both parasites were observed in the haemolymph, gills and hepatopancreas. The prevalence of clinical infections (i.e. parasites seen directly in fresh haemolymph preparations) was low, at ~1%, whereas subclinical levels, detected by polymerase chain reaction, were slightly higher at ~2%. Although no spores were found in any of the infected crabs examined histologically (n = 334), the morphology of monokaryotic and dikaryotic unicellular stages of the parasites enabled differentiation between the two new species. Phylogenetic analyses of the new species based on the small subunit (SSU) rDNA gene placed H. cranc in a clade of otherwise uncharacterized environmental sequences from marine samples, and H. carcini in a clade with other crustacean-associated lineages.
A sphere sinking through a chemical gradient drags fluid with it, deforming the gradient. The sphere leaves a trail of gradient enhancement that persists longer than the velocity disturbance in the Reynolds
$10^{-2}\leqslant Re\leqslant 10^{2}$
, Froude
$10^{-1}\leqslant Fr\leqslant 10^{3}$
and Péclet
$10^{2}<Pe\leqslant 10^{6}$
regime considered here. We quantify the enhancement of the gradient and the diffusive flux in the trail of disturbed chemical left by the passing sphere using a combination of numerical simulations and scaling analyses. When
$Fr$
is large and buoyancy forces are negligible, dragged isosurfaces of chemical form a boundary layer of thickness
$\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}$
around the sphere with diameter
$l$
. We derive the scaling
$\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}/l\sim \mathit{Pe}^{-1/3}$
from the balance of advection and diffusion in the chemical boundary layer. The sphere displaces a single isosurface of chemical a maximum distance
$\mathit{L}_{Def}$
that increases as
$\mathit{L}_{Def}/l\sim l/\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}\sim \mathit{Pe}^{1/3}$
. Increased flux through the chemical boundary layer moving with the sphere is described by a Sherwood number,
$Sh\sim l/\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}\sim \mathit{Pe}^{1/3}$
. The gradient enhancement trail extends much farther than
$\mathit{L}_{Def}$
as displaced isosurfaces slowly return to their original positions through diffusion. In the reference frame of a chemical isosurface moving past the sphere, a new quantity describing the Lagrangian flux is found to scale as
$\mathit{M}\sim (\mathit{L}_{Def}/l)^{2}\sim \mathit{Pe}^{2/3}$
. The greater
$\mathit{Pe}$
dependence of
$\mathit{M}$
versus
$Sh$
demonstrates the importance of the deformation trail for determining the total flux of chemical in the system. For
$\mathit{Fr}\geqslant 10$
, buoyancy forces are weak compared to the motion of the sphere and the preceding results are retained. Below
$\mathit{Fr}=10$
, an additional Froude dependence is found and
$l/\unicode[STIX]{x1D6FF}_{\unicode[STIX]{x1D70C}}\sim Sh\sim Re^{1/6}Fr^{-1/6}Pe^{1/3}$
. Buoyancy forces suppress gradient deformation downstream, resulting in
$\mathit{L}_{Def}/l\sim Re^{-1/3}Fr^{1/3}Pe^{1/3}$
and
$\mathit{M}\sim Re^{-1/3}Fr^{1/3}Pe^{2/3}$
. The productivity of marine plankton – and therefore global carbon and oxygen cycles – depends on the availability of microscale gradients of chemicals. Because most plankton exist in the fluids regime under consideration, this work describes a new mechanism by which sinking particles and plankton can stir weak ambient chemical gradients a distance
$\mathit{L}_{Def}$
and increase chemical flux in the trail by a factor of
$\mathit{M}$
.
Archaeological research in the Maya lowlands has identified special deposits that offer essential information about the abandonment of Classic Maya centers. We argue that some of the “problematical deposits” associated with terminal architecture may be more accurately described as peri-abandonment deposits since they temporally and behaviorally relate to the activities associated with the final use of ceremonial space. Here, we describe several peri-abandonment deposits that were identified in Group B at the site of Baking Pot, located in western Belize. Using detailed stratigraphic and contextual information, artifact assemblages, and calendar dates recorded on polychrome vessels recovered in the deposits, we describe the nature of activities associated with the formation of peri-abandonment deposits at Baking Pot in the eighth to ninth centuries. We find patterning in the spatial locations of deposits in the corners of plazas and courtyards at Baking Pot, with variability in artifact assemblages between specific deposits.
Astrophysics Telescope for Large Area Spectroscopy Probe is a concept for a National Aeronautics and Space Administration probe-class space mission that will achieve ground-breaking science in the fields of galaxy evolution, cosmology, Milky Way, and the Solar System. It is the follow-up space mission to Wide Field Infrared Survey Telescope (WFIRST), boosting its scientific return by obtaining deep 1–4 μm slit spectroscopy for ∼70% of all galaxies imaged by the ∼2 000 deg2 WFIRST High Latitude Survey at z > 0.5. Astrophysics Telescope for Large Area Spectroscopy will measure accurate and precise redshifts for ∼200 M galaxies out to z < 7, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history. Astrophysics Telescope for Large Area Spectroscopy Probe and WFIRST together will produce a 3D map of the Universe over 2 000 deg2, the definitive data sets for studying galaxy evolution, probing dark matter, dark energy and modifications of General Relativity, and quantifying the 3D structure and stellar content of the Milky Way. Astrophysics Telescope for Large Area Spectroscopy Probe science spans four broad categories: (1) Revolutionising galaxy evolution studies by tracing the relation between galaxies and dark matter from galaxy groups to cosmic voids and filaments, from the epoch of reionisation through the peak era of galaxy assembly; (2) Opening a new window into the dark Universe by weighing the dark matter filaments using 3D weak lensing with spectroscopic redshifts, and obtaining definitive measurements of dark energy and modification of General Relativity using galaxy clustering; (3) Probing the Milky Way’s dust-enshrouded regions, reaching the far side of our Galaxy; and (4) Exploring the formation history of the outer Solar System by characterising Kuiper Belt Objects. Astrophysics Telescope for Large Area Spectroscopy Probe is a 1.5 m telescope with a field of view of 0.4 deg2, and uses digital micro-mirror devices as slit selectors. It has a spectroscopic resolution of R = 1 000, and a wavelength range of 1–4 μm. The lack of slit spectroscopy from space over a wide field of view is the obvious gap in current and planned future space missions; Astrophysics Telescope for Large Area Spectroscopy fills this big gap with an unprecedented spectroscopic capability based on digital micro-mirror devices (with an estimated spectroscopic multiplex factor greater than 5 000). Astrophysics Telescope for Large Area Spectroscopy is designed to fit within the National Aeronautics and Space Administration probe-class space mission cost envelope; it has a single instrument, a telescope aperture that allows for a lighter launch vehicle, and mature technology (we have identified a path for digital micro-mirror devices to reach Technology Readiness Level 6 within 2 yr). Astrophysics Telescope for Large Area Spectroscopy Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way.
We sought to define the prevalence of echocardiographic abnormalities in long-term survivors of paediatric hematopoietic stem cell transplantation and determine the utility of screening in asymptomatic patients. We analysed echocardiograms performed on survivors who underwent hematopoietic stem cell transplantation from 1982 to 2006. A total of 389 patients were alive in 2017, with 114 having an echocardiogram obtained ⩾5 years post-infusion. A total of 95 patients had echocardiogram performed for routine surveillance. The mean time post-hematopoietic stem cell transplantation was 13 years. Of 95 patients, 77 (82.1%) had ejection fraction measured, and 10/77 (13.0%) had ejection fraction z-scores ⩽−2.0, which is abnormally low. Those patients with abnormal ejection fraction were significantly more likely to have been exposed to anthracyclines or total body irradiation. Among individuals who received neither anthracyclines nor total body irradiation, only 1/31 (3.2%) was found to have an abnormal ejection fraction of 51.4%, z-score −2.73. In the cohort of 77 patients, the negative predictive value of having a normal ejection fraction given no exposure to total body irradiation or anthracyclines was 96.7% at 95% confidence interval (83.3–99.8%). Systolic dysfunction is relatively common in long-term survivors of paediatric hematopoietic stem cell transplantation who have received anthracyclines or total body irradiation. Survivors who are asymptomatic and did not receive radiation or anthracyclines likely do not require surveillance echocardiograms, unless otherwise indicated.
Motivated by the dynamics within terrestrial bodies, we consider a rotating, strongly thermally stratified fluid within a spherical shell subject to a prescribed laterally inhomogeneous heat-flux condition at the outer boundary. Using a numerical model, we explore a broad range of three key dimensionless numbers: a thermal stratification parameter (the relative size of boundary temperature gradients to imposed vertical temperature gradients),
$10^{-3}\leqslant S\leqslant 10^{4}$
, a buoyancy parameter (the strength of applied boundary heat-flux anomalies),
$10^{-2}\leqslant B\leqslant 10^{6}$
, and the Ekman number (ratio of viscous to Coriolis forces),
$10^{-6}\leqslant E\leqslant 10^{-4}$
. We find both steady and time-dependent solutions and delineate the regime boundaries. We focus on steady-state solutions, for which a clear transition is found between a low
$S$
regime, in which buoyancy dominates the dynamics, and a high
$S$
regime, in which stratification dominates. For the low-
$S$
regime, we find that the characteristic flow speed scales as
$B^{2/3}$
, whereas for high-
$S$
, the radial and horizontal velocities scale respectively as
$u_{r}\sim S^{-1}$
,
$u_{h}\sim S^{-3/4}B^{1/4}$
and are confined within a thin layer of depth
$(SB)^{-1/4}$
at the outer edge of the domain. For the Earth, if lower mantle heterogeneous structure is due principally to chemical anomalies, we estimate that the core is in the high-
$S$
regime and steady flows arising from strong outer boundary thermal anomalies cannot penetrate the stable layer. However, if the mantle heterogeneities are due to thermal anomalies and the heat-flux variation is large, the core will be in a low-
$S$
regime in which the stable layer is likely penetrated by boundary-driven flows.
To determine the feasibility and value of developing a regional antibiogram for community hospitals.
DESIGN
Multicenter retrospective analysis of antibiograms.
SETTING AND PARTICIPANTS
A total of 20 community hospitals in central and eastern North Carolina and south central Virginia participated in this study.
METHODS
We combined antibiogram data from participating hospitals for 13 clinically relevant gram-negative pathogen–antibiotic combinations. From this combined antibiogram, we developed a regional antibiogram based on the mean susceptibilities of the combined data.
RESULTS
We combined a total of 69,778 bacterial isolates across 13 clinically relevant gram-negative pathogen–antibiotic combinations (median for each combination, 1100; range, 174–27,428). Across all pathogen–antibiotic combinations, 69% of local susceptibility rates fell within 1 SD of the regional mean susceptibility rate, and 97% of local susceptibilities fell within 2 SD of the regional mean susceptibility rate. No individual hospital had >1 pathogen–antibiotic combination with a local susceptibility rate >2 SD of the regional mean susceptibility rate. All hospitals’ local susceptibility rates were within 2 SD of the regional mean susceptibility rate for low-prevalence pathogens (<500 isolates cumulative for the region).
CONCLUSIONS
Small community hospitals frequently cannot develop an accurate antibiogram due to a paucity of local data. A regional antibiogram is likely to provide clinically useful information to community hospitals for low-prevalence pathogens.
The History, Electrocardiogram (ECG), Age, Risk Factors, and Troponin (HEART) score is a decision aid designed to risk stratify emergency department (ED) patients with acute chest pain. It has been validated for ED use, but it has yet to be evaluated in a prehospital setting.
Hypothesis
A prehospital modified HEART score can predict major adverse cardiac events (MACE) among undifferentiated chest pain patients transported to the ED.
Methods
A retrospective cohort study of patients with chest pain transported by two county-based Emergency Medical Service (EMS) agencies to a tertiary care center was conducted. Adults without ST-elevation myocardial infarction (STEMI) were included. Inter-facility transfers and those without a prehospital 12-lead ECG or an ED troponin measurement were excluded. Modified HEART scores were calculated by study investigators using a standardized data collection tool for each patient. All MACE (death, myocardial infarction [MI], or coronary revascularization) were determined by record review at 30 days. The sensitivity and negative predictive values (NPVs) for MACE at 30 days were calculated.
Results
Over the study period, 794 patients met inclusion criteria. A MACE at 30 days was present in 10.7% (85/794) of patients with 12 deaths (1.5%), 66 MIs (8.3%), and 12 coronary revascularizations without MI (1.5%). The modified HEART score identified 33.2% (264/794) of patients as low risk. Among low-risk patients, 1.9% (5/264) had MACE (two MIs and three revascularizations without MI). The sensitivity and NPV for 30-day MACE was 94.1% (95% CI, 86.8-98.1) and 98.1% (95% CI, 95.6-99.4), respectively.
Conclusions
Prehospital modified HEART scores have a high NPV for MACE at 30 days. A study in which prehospital providers prospectively apply this decision aid is warranted.
Convection in the metallic cores of terrestrial planets is likely to be subjected to lateral variations in heat flux through the outer boundary imposed by creeping flow in the overlying silicate mantles. Boundary anomalies can significantly influence global diagnostics of core convection when the Rayleigh number,
$Ra$
, is weakly supercritical; however, little is known about the strongly supercritical regime appropriate for planets. We perform numerical simulations of rapidly rotating convection in a spherical shell geometry and impose two patterns of boundary heat flow heterogeneity: a hemispherical
$Y_{1}^{1}$
spherical harmonic pattern; and one derived from seismic tomography of the Earth’s lower mantle. We consider Ekman numbers
$10^{-4}\leqslant E\leqslant 10^{-6}$
, flux-based Rayleigh numbers up to
${\sim}800$
times critical, and a Prandtl number of unity. The amplitude of the lateral variation in heat flux is characterised by
$q_{L}^{\ast }=0$
, 2.3, 5.0, the peak-to-peak amplitude of the outer boundary heat flux divided by its mean. We find that the Nusselt number,
$Nu$
, can be increased by up to
${\sim}25\,\%$
relative to the equivalent homogeneous case due to boundary-induced correlations between the radial velocity and temperature anomalies near the top of the shell. The
$Nu$
enhancement tends to become greater as the amplitude and length scale of the boundary heterogeneity are increased and as the system becomes more supercritical. This
$Ra$
dependence can steepen the
$Nu\propto Ra^{\unicode[STIX]{x1D6FE}}$
scaling in the rotationally dominated regime, with
$\unicode[STIX]{x1D6FE}$
for our most extreme case approximately 20 % greater than the equivalent homogeneous scaling. Therefore, it may be important to consider boundary heterogeneity when extrapolating numerical results to planetary conditions.
Giant ragweed has been increasing as a major weed of row crops in the last
30 yr, but quantitative data regarding its pattern and mechanisms of spread
in crop fields are lacking. To address this gap, we conducted a Web-based
survey of certified crop advisors in the U.S. Corn Belt and Ontario, Canada.
Participants were asked questions regarding giant ragweed and crop
production practices for the county of their choice. Responses were mapped
and correlation analyses were conducted among the responses to determine
factors associated with giant ragweed populations. Respondents rated giant
ragweed as the most or one of the most difficult weeds to manage in 45% of
421 U.S. counties responding, and 57% of responding counties reported giant
ragweed populations with herbicide resistance to acetolactate synthase
inhibitors, glyphosate, or both herbicides. Results suggest that giant
ragweed is increasing in crop fields outward from the east-central U.S. Corn
Belt in most directions. Crop production practices associated with giant
ragweed populations included minimum tillage, continuous soybean, and
multiple-application herbicide programs; ecological factors included giant
ragweed presence in noncrop edge habitats, early and prolonged emergence,
and presence of the seed-burying common earthworm in crop fields. Managing
giant ragweed in noncrop areas could reduce giant ragweed migration from
noncrop habitats into crop fields and slow its spread. Where giant ragweed
is already established in crop fields, including a more diverse combination
of crop species, tillage practices, and herbicide sites of action will be
critical to reduce populations, disrupt emergence patterns, and select
against herbicide-resistant giant ragweed genotypes. Incorporation of a
cereal grain into the crop rotation may help suppress early giant ragweed
emergence and provide chemical or mechanical control options for
late-emerging giant ragweed.
Palmer amaranth and waterhemp have become increasingly troublesome weeds throughout the United States. Both species are highly adaptable and emerge continuously throughout the summer months, presenting the need for a residual PRE application in soybean. To improve season-long control of Amaranthus spp., 19 PRE treatments were evaluated on glyphosate-resistant Palmer amaranth in 2013 and 2014 at locations in Arkansas, Indiana, Nebraska, Illinois, and Tennessee; and on glyphosate-resistant waterhemp at locations in Illinois, Missouri, and Nebraska. The two Amaranthus species were analyzed separately; data for each species were pooled across site-years, and site-year was included as a random variable in the analyses. The dissipation of weed control throughout the course of the experiments was compared among treatments with the use of regression analysis where percent weed control was described as a function of time (the number of weeks after treatment [WAT]). At the mean (i.e., average) WAT (4.3 and 3.2 WAT for Palmer amaranth and waterhemp, respectively) isoxaflutole + S-metolachlor + metribuzin had the highest predicted control of Palmer amaranth (98%) and waterhemp (99%). Isoxaflutole + S-metolachlor + metribuzin, S-metolachlor + mesotrione, and flumioxazin + pyroxasulfone had a predicted control ≥ 97% and similar model parameter estimates, indicating control declined at similar rates for these treatments. Dicamba and 2,4-D provided some, short-lived residual control of Amaranthus spp. When dicamba was added to metribuzin or S-metolachlor, control increased compared to dicamba alone. Flumioxazin + pyroxasulfone, a currently labeled PRE, performed similarly to treatments containing isoxaflutole or mesotrione. Additional sites of action will provide soybean growers more opportunities to control these weeds and reduce the potential for herbicide resistance.
Herbicide-resistant Amaranthus spp. continue to cause management difficulties in soybean. New soybean technologies under development, including resistance to various combinations of glyphosate, glufosinate, dicamba, 2,4-D, isoxaflutole, and mesotrione, will make possible the use of additional herbicide sites of action in soybean than is currently available. When this research was conducted, these soybean traits were still regulated and testing herbicide programs with the appropriate soybean genetics in a single experiment was not feasible. Therefore, the effectiveness of various herbicide programs (PRE herbicides followed by POST herbicides) was evaluated in bare-ground experiments on glyphosate-resistant Palmer amaranth and glyphosate-resistant waterhemp (both tall and common) at locations in Arkansas, Illinois, Indiana, Missouri, Nebraska, and Tennessee. Twenty-five herbicide programs were evaluated; 5 of which were PRE herbicides only, 10 were PRE herbicides followed by POST herbicides 3 to 4 wks after (WA) the PRE application (EPOST), and 10 were PRE herbicides followed by POST herbicides 6 to 7 WA the PRE application (LPOST). Programs with EPOST herbicides provided 94% or greater control of Palmer amaranth and waterhemp at 3 to 4 WA the EPOST. Overall, programs with LPOST herbicides resulted in a period of weed emergence in which weeds would typically compete with a crop. Weeds were not completely controlled with the LPOST herbicides because weed sizes were larger (≥ 15 cm) compared with their sizes at the EPOST application (≤ 7 cm). Most programs with LPOST herbicides provided 80 to 95% control at 3 to 4 WA applied LPOST. Based on an orthogonal contrast, using a synthetic-auxin herbicide LPOST improves control of Palmer amaranth and waterhemp over programs not containing a synthetic-auxin LPOST. These results show herbicides that can be used in soybean and that contain auxinic- or HPPD-resistant traits will provide growers with an opportunity for better control of glyphosate-resistant Palmer amaranth and waterhemp over a wide range of geographies and environments.
Nitrous oxide (N2O) is a potent greenhouse gas with implication
for climate change. Agriculture accounts for 10% of all greenhouse gas
emissions in the United States, but 75% of the country's N2O
emissions. In the absence of PRE herbicides, weeds compete with soybean for
available soil moisture and inorganic N, and may reduce N2O
emissions relative to a weed-free environment. However, after weeds are
killed with a POST herbicide, the dead weed residues may stimulate
N2O emissions by increasing soil moisture and supplying carbon
and nitrogen to microbial denitrifiers. Wider soybean rows often have more
weed biomass, and as a result, row width may further impact how weeds
influence N2O emissions. To determine this relationship, field
studies were conducted in 2013 and 2014 in Arlington, WI. A two-by-two
factorial treatment structure of weed management (PRE + POST vs. POST-only)
and row width (38 or 76 cm) was arranged in a randomized complete block
design with four replications. N2O fluxes were measured from
static gas sampling chambers at least weekly starting 2 wk after planting
until mid-September, and were compared for the periods before and after weed
termination using a repeated measures analysis. N2O fluxes were
not influenced by the weed by width
interaction or width before termination, after termination,
or for the full duration of the study at P ≤ 0.05. Interestingly, we
observed that POST-only treatments had lower fluxes on the sampling day
immediately prior to POST application (P = 0.0002), but this was the only
incidence where weed influenced N2O fluxes, and
overall, average fluxes from PRE + POST and POST-only treatments were not
different for any period of the study. Soybean yield was not influenced by
width (P = 0.6018) or weed by
width (P = 0.5825), but yield was 650 kg ha−1
higher in the PRE + POST than POST-only treatments (P = 0.0007). These
results indicate that herbicide management strategy does not influence
N2O emissions from soybean, and the use of a PRE herbicide
prevents soybean yield loss.
Quantitative results for the linear stability of planar Stokes layers subject to small, high-frequency perturbations are obtained for both a narrow channel and a flow approximating the classical semi-infinite Stokes layer. Previous theoretical and experimental predictions of the critical Reynolds number for the classical flat Stokes layer have differed widely with the former exceeding the latter by a factor of two or three. Here it is demonstrated that only a 1 % perturbation, at an appropriate frequency, to the nominal sinusoidal wall motion is enough to result in a reduction of the theoretical critical Reynolds number of as much as 60 %, bringing the theoretical conditions much more in line with the experimentally reported values. Furthermore, within the various experimental observations there is a wide variation in reported critical conditions and the results presented here may provide a new explanation for this behaviour.
The Bovine Respiratory Disease Coordinated Agricultural Project (BRD CAP) is a 5-year project funded by the United States Department of Agriculture (USDA), with an overriding objective to use the tools of modern genomics to identify cattle that are less susceptible to BRD. To do this, two large genome wide association studies (GWAS) were conducted using a case:control design on preweaned Holstein dairy heifers and beef feedlot cattle. A health scoring system was used to identify BRD cases and controls. Heritability estimates for BRD susceptibility ranged from 19 to 21% in dairy calves to 29.2% in beef cattle when using numerical scores as a semi-quantitative definition of BRD. A GWAS analysis conducted on the dairy calf data showed that single nucleotide polymorphism (SNP) effects explained 20% of the variation in BRD incidence and 17–20% of the variation in clinical signs. These results represent a preliminary analysis of ongoing work to identify loci associated with BRD. Future work includes validation of the chromosomal regions and SNPs that have been identified as important for BRD susceptibility, fine mapping of chromosomes to identify causal SNPs, and integration of predictive markers for BRD susceptibility into genetic tests and national cattle genetic evaluations.