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Among outpatients with coronavirus disease 2019 (COVID-19) due to the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) δ (delta) variant who did and did not receive 2 vaccine doses at 7 days after symptom onset, there was no difference in viral shedding (cycle threshold difference 0.59, 95% CI, −4.68 to 3.50; P = .77) with SARS-CoV-2 cultured from 2 (7%) of 28 and 1 (4%) of 26 outpatients, respectively.
We establish sharp bounds for the second moment of symmetric-square L-functions attached to Hecke Maass cusp forms
$u_j$
with spectral parameter
$t_j$
, where the second moment is a sum over
$t_j$
in a short interval. At the central point
$s=1/2$
of the L-function, our interval is smaller than previous known results. More specifically, for
$\left \lvert t_j\right \rvert $
of size T, our interval is of size
$T^{1/5}$
, whereas the previous best was
$T^{1/3}$
, from work of Lam. A little higher up on the critical line, our second moment yields a subconvexity bound for the symmetric-square L-function. More specifically, we get subconvexity at
$s=1/2+it$
provided
$\left \lvert t_j\right \rvert ^{6/7+\delta }\le \lvert t\rvert \le (2-\delta )\left \lvert t_j\right \rvert $
for any fixed
$\delta>0$
. Since
$\lvert t\rvert $
can be taken significantly smaller than
$\left \lvert t_j\right \rvert $
, this may be viewed as an approximation to the notorious subconvexity problem for the symmetric-square L-function in the spectral aspect at
$s=1/2$
.
Scanning transmission X-ray microscopy is a powerful method for mapping chemical phases in nano-materials. The point spread function (PSF) of a conventional zone-plate-based microscope limits the achievable spatial resolution and also results in spatially resolved spectra that do not accurately reflect the spatial heterogeneity of the samples when the scale of the detail approaches the probe size. X-ray ptychography, a coherent-scattering-based imaging scheme that effectively removes the probe from the image data, returns accurate spectra from regions smaller than the probe size. We show through simulation how the long tails on the PSF of an x-ray optic can cause spectral distortion near a boundary between two spectrally distinct regions. The resulting apparent point spectra can appear mixed, with the species on one side of the boundary seeming to be present on the other even at a distance from the boundary equal to several times the spatial resolution. We further demonstrate the effect experimentally and show that ptychographic microscopy can return the expected spectra from a model system, whereas conventional microscopy does not.
High-temperature differential scanning calorimetry was used to understand the thermal properties of Si-rich metal–silicon alloys. Insoluble metals (A and B) were found to produce an alloy with discrete ASi2 and BSi2 dispersed phases. In contrast, metals that form a solid solution result in a dispersed phase that has a composition of AxB1−xSi2, where x varies continuously across each inclusion. This complex composition distribution is putatively caused by differences in the solidification temperatures of ASi2 versus BSi2. Though this behavior was observed for several different combinations of metals, we focus here specifically on the Cr/V/Si system. To better understand the range and most probable element concentrations in the dispersed silicide domains, a method was devised to generate histograms of their Cr and V concentrations from energy-dispersive X-ray spectroscopy hyperspectral images. Varying the Cr/V/Si ratio was found to change the shape of the element histograms, indicating that the distribution of silicide compositions that form is controlled by the input composition. Adding aluminum was found to result in dispersed phases that had a single composition rather than a range of Cr and V concentrations. This demonstrates that aluminum can be an effective additive for altering solidification kinetics in silicon alloys.
Widespread testing for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) is necessary to curb the spread of coronavirus disease 2019 (COVID-19), but testing is undermined when the only option is a nasopharyngeal swab. Self-collected swab techniques can overcome many of the disadvantages of a nasopharyngeal swab, but they require evaluation.
Methods:
Three self-collected non-nasopharyngeal swab techniques (saline gargle, oral swab and combined oral-anterior nasal swab) were compared to a nasopharyngeal swab for SARS-CoV-2 detection at multiple COVID-19 assessment centers in Toronto, Canada. The performance characteristics of each test were assessed.
Results:
The adjusted sensitivity of the saline gargle was 0.90 (95% CI 0.86-0.94), the oral swab was 0.82 (95% CI, 0.72–0.89) and the combined oral–anterior nasal swab was 0.87 (95% CI, 0.77–0.93) compared to a nasopharyngeal swab, which demonstrated a sensitivity of ˜90% when all positive tests were the reference standard. The median cycle threshold values for the SARS-CoV-2 E-gene for concordant and discordant saline gargle specimens were 17 and 31 (P < .001), for the oral swabs these values were 17 and 28 (P < .001), and for oral–anterior nasal swabs these values were 18 and 31 (P = .007).
Conclusions:
Self-collected saline gargle and an oral–anterior nasal swab have a similar sensitivity to a nasopharyngeal swab for the detection of SARS-CoV-2. These alternative collection techniques are cheap and can eliminate barriers to testing, particularly in underserved populations.
The purpose of this paper is to build on personal engagement and role theory to develop a conceptual definition of engagement to different organizational roles (job, organization, supervisor, and coworkers) and create and validate the Role-Based Engagement Scale (RBES). Data were collected from four samples (n = 1,302) of employees, including three from multiple organizations and one from an aircraft manufacturer. Results across three studies consistently support the four dimension structure of the RBES, its internal consistency, convergent, discriminant, and predictive validity based on a series of confirmatory factor analyses. The RBES is a psychometrically sound instrument that measures engagement to job, organization, supervisor, and coworkers. This instrument will provide more targeted information for human resource management (HRM) professionals tasked with developing training methods and processes to improve low-scoring dimensions of engagement, optimizing HRM interventions.
The purpose of this article is to describe the process of developing and implementing a transdisciplinary community-based research center, the Center for Health Equity Research (CHER) Chicago, to offer a model for designing and implementing research centers that aim to address structural causes of health inequality.
Methods:
Scholars from diverse backgrounds and disciplines formed a multidisciplinary team for the Center and adopted the structural violence framework as the organizing conceptual model. All Center activities were based on community partnership. The Center activities were organized within three cores: administrative, investigator development, and community engagement and dissemination cores. The key activities during the first year were to develop a pilot grant program for early-stage investigators (ESIs) and to establish community partnership mechanisms.
Results:
CHER provided more than 60 consultations for ESIs, which resulted in 31 pilot applications over the three application cycles. Over 200 academic and community partners attended the community symposium and discussed community priority. Some challenges encountered were to improve communication among investigators, to clarify roles and responsibilities of the three cores, and to build consensus on the definition and operationalization of the concept of structural violence.
Conclusion:
There is an increasing need for local hubs to facilitate transdisciplinary collaboration and community engagement to effectively address health inequity. Building consensus around a shared vision among partners is a difficult and yet important step toward achieving equity.
Childhood maltreatment is one of the strongest predictors of adulthood depression and alterations to circulating levels of inflammatory markers is one putative mechanism mediating risk or resilience.
Aims
To determine the effects of childhood maltreatment on circulating levels of 41 inflammatory markers in healthy individuals and those with a major depressive disorder (MDD) diagnosis.
Method
We investigated the association of childhood maltreatment with levels of 41 inflammatory markers in two groups, 164 patients with MDD and 301 controls, using multiplex electrochemiluminescence methods applied to blood serum.
Results
Childhood maltreatment was not associated with altered inflammatory markers in either group after multiple testing correction. Body mass index (BMI) exerted strong effects on interleukin-6 and C-reactive protein levels in those with MDD.
Conclusions
Childhood maltreatment did not exert effects on inflammatory marker levels in either the participants with MDD or the control group in our study. Our results instead highlight the more pertinent influence of BMI.
Declaration of interest
D.A.C. and H.W. work for Eli Lilly Inc. R.N. has received speaker fees from Sunovion, Jansen and Lundbeck. G.B. has received consultancy fees and funding from Eli Lilly. R.H.M.-W. has received consultancy fees or has a financial relationship with AstraZeneca, Bristol-Myers Squibb, Cyberonics, Eli Lilly, Ferrer, Janssen-Cilag, Lundbeck, MyTomorrows, Otsuka, Pfizer, Pulse, Roche, Servier, SPIMACO and Sunovian. I.M.A. has received consultancy fees or has a financial relationship with Alkermes, Lundbeck, Lundbeck/Otsuka, and Servier. S.W. has sat on an advisory board for Sunovion, Allergan and has received speaker fees from Astra Zeneca. A.H.Y. has received honoraria for speaking from Astra Zeneca, Lundbeck, Eli Lilly, Sunovion; honoraria for consulting from Allergan, Livanova and Lundbeck, Sunovion, Janssen; and research grant support from Janssen. A.J.C. has received honoraria for speaking from Astra Zeneca, honoraria for consulting with Allergan, Livanova and Lundbeck and research grant support from Lundbeck.
We prove that if $k$ and $\ell$ are sufficiently large, then all the zeros of the weight $k+\ell$ cusp form $E_{k}(z)E_{\ell }(z)-E_{k+\ell }(z)$ in the standard fundamental domain lie on the boundary. We, moreover, find formulas for the number of zeros on the bottom arc with $|z|=1$, and those on the sides with $Re(z)=\pm 1/2$. One important ingredient of the proof is an approximation of the Eisenstein series in terms of the Jacobi theta function.
Anecdotal observations of improved glyphosate efficacy on glyphosate-resistant (GR) tall waterhemp populations in corn production compared with soybean suggested the presence of nitrogen (N) fertilizer may influence the expression of glyphosate resistance. Greenhouse and field experiments were conducted to determine the influence of soil-applied nitrogen fertilizer on the growth rate and sensitivity of glyphosate-susceptible (GS) and GR tall waterhemp and Palmer amaranth. The addition of supplemental fertilizer increased the relative growth rate (plant height and shoot volume), number of nodes, and percentage of shoot nodes with axillary branches on GS and GR biotypes of both weed species. The axillary bud activity was increased 52 and 8% with increasing N for the GR and GS biotypes of tall waterhemp and Palmer amaranth, respectively. The GS populations of tall waterhemp and Palmer amaranth were more sensitive to glyphosate in the greenhouse under increased fertilizer levels compared with no fertilizer. Additionally, GR tall waterhemp was more sensitive to glyphosate under the higher fertilizer treatments, which resulted in a reduction in the calculated resistance factor (RF) from 27.8 under no fertilizer to 4.7 for the high fertilizer treatment. The RF for GR Palmer amaranth was not influenced by the fertilizer treatments in the greenhouse. Field experiments demonstrated that glyphosate efficacy may be greater on GR populations of tall waterhemp and Palmer amaranth under high N conditions, but these results were not consistent and most likely were influenced by soil moisture in 2012, which was more limiting than N supply. This research implies that soil fertility can influence the sensitivity of some GR weed species to glyphosate and the RF. Therefore, the evolution and management of GR weed species in commercial crop production may be influenced by the nutrient status of the soil and the use of supplemental fertilizers.
The interaction of the barotropic tide with a tall, two-dimensional ridge is examined analytically and numerically at latitudes where the tide is subinertial, and contrasted to when the tide is superinertial. When the tide is subinertial, the energy density associated with the response grows with latitude as both the oscillatory along-ridge flow and near-ridge isopycnal displacement become large. Where $f\neq 0$, nonlinear processes lead to the formation of along-ridge jets, which become faster at high latitudes. Dissipation and mixing is larger, and peaks later in the tidal cycle when the tide is subinertial compared with when the tide is superinertial. Mixing occurs mainly on the flanks of the topography in both cases, though a superinertial tide may additionally generate mixing above topography arising from convective breaking of radiating waves.
We apply n- and p-type polycrystalline silicon (poly-Si) films on tunneling SiOx to form passivated contacts to n-type Si wafers. The resulting induced emitter and n+/n back surface field junctions of high carrier selectivity and low contact resistivity enable high efficiency Si solar cells. This work addresses the materials science of their performance governed by the properties of the individual layers (poly-Si, tunneling oxide) and more importantly, by the process history of the cell as a whole. Tunneling SiOx layers (<2 nm) are grown thermally or chemically, followed by a plasma enhanced chemical vapor deposition growth of p+ or n+ doped a-Si:H. The latter is thermally crystallized into poly-Si, resulting in grain nucleation and growth as well as dopant diffusion within the poly-Si and penetration through the tunneling oxide into the Si base wafer. The cell process is designed to improve the passivation of both oxide interfaces and tunneling transport through the oxide. A novel passivation technique involves coating of the passivated contact and whole cell with atomic layer deposited Al2O3 and activating them at 400 °C. The resulting excellent passivation persists after subsequent chemical removal of the Al2O3. The preceding cell process steps must be carefully tailored to avoid structural and morphological defects, as well as to maintain or improve passivation, and carrier selective transport. Furthermore, passivated contact metallization presents significant challenges, often resulting in passivation loss. Suggested remedies include improved Si cell wafer surface morphology (without micropyramids) and postdeposited a-Si:H capping layers over the poly-Si.
Fall-applied residual and spring preplant burn-down herbicide applications are typically used to control winter annual weeds and may also provide early-season residual control of summer annual weed species such as giant ragweed. Field experiments were conducted from 2006 to 2008 in southern Illinois to (1) assess the emergence pattern of giant ragweed, (2) evaluate the efficacy of several herbicides commonly used for soil-residual control of giant ragweed, and (3) investigate the optimal application timing of soil-residual herbicides for control of giant ragweed. Six herbicide treatments were applied at four application timings: early fall, late fall, early spring, and late spring. Giant ragweed first emerged in mid- and late-March in 2007 and 2008, respectively. The duration of emergence varied by year, with 95% of emergence complete in late May of 2008, but not until early July in 2007. Giant ragweed emergence occurred more quickly in plots that received a fall application of glyphosate + 2,4-D compared with the nontreated. Fall-applied residual herbicides did not reduce giant ragweed emergence in 2007 when compared with the nontreated, with the exception of chlorimuron + tribenuron applied in late fall. Giant ragweed control from early- and late-spring herbicide applications was variable by year. In 2007, saflufenacil (50 and 100 g ai ha−1) and simazine applied in early spring reduced giant ragweed densities by 95% or greater through mid-May; however, in 2008, early-spring applications failed to reduce giant ragweed emergence in mid-April. The only treatments that reduced giant ragweed densities by > 80% through early July were late-spring applications of chlorimuron + tribenuron or saflufenacil at 100 g ha−1. Thus, the emergence patterns of giant ragweed in southern Illinois dictates that best management with herbicides would include late-spring applications of soil-residual herbicides just before crop planting and most likely requires subsequent control with foliar or soil-residual herbicides after crop emergence.
Greenhouse studies were conducted to determine the influence of spray-solution pH, adjuvant, light intensity, temperature, and glyphosate on the efficacy of saflufenacil on horseweed. Control of glyphosate-resistant horseweed from saflufenacil alone was greatest with a spray-solution pH of 5, compared with pH 7 or 9. However, when glyphosate was added to saflufenacil, similar GR50 values were measured with spray solutions adjusted to pH 5 and 9, and horseweed control at pH 9 was 38% greater than at pH 7. The efficacy of saflufenacil on horseweed was 36% greater when crop oil concentrate was used as an adjuvant compared with nonionic surfactant, regardless of the addition of glyphosate or the sensitivity of the horseweed population to glyphosate (resistant vs. susceptible). The addition of glyphosate to low rates of saflufenacil increased control over saflufenacil applied alone on glyphosate-susceptible and -resistant horseweed. Saflufenacil activity was greater under low light intensity (300 μmol m−2 s−1) than high light intensity (1,000 μmol m−2 s−1). Although initial horseweed control was greater under high temperature (27 C) compared with low temperature (10 C), by 21 d after treatment horseweed dry weight was similar from saflufenacil applied under high and low temperatures.
Isolation can provide marine ecosystems with a refuge from human impacts. However, information on the biodiversity, ecology and fisheries of remote regions is often sparse. The proposed Coral Sea Marine Reserve could create one of the world's largest and most remote marine parks, yet little information is available to inform discussions. Fish captures from the Coral Sea and adjacent Great Barrier Reef (GBR) were assessed from reports contained in a chronology of spearfishing publications from 1953 to 2009, and reveal for the first time the history of recreational spearfishing in the Coral Sea. Although the area is perceived as relatively untouched, the data indicate that spearfishers have frequented Coral Sea reefs for at least 43 years and reported captures have increased exponentially. Post-1993 trophy captures in the Coral Sea (mean 23 kg) were larger than the adjacent GBR (9 kg). Reef species characterize the GBR catch, while large pelagic species characterize the Coral Sea catch. Provided that functionally important fishes are not targeted, the relatively small scale of recreational spearfishing and the focus on pelagic species suggests that spearfishing currently exerts limited pressure on the ecology of Coral Sea reefs.
Waterhemp resistance to foliar applications of protoporphyrinogen oxidase (PPO)–inhibiting herbicides has become increasingly disconcerting given the widespread distribution of glyphosate resistance. Fortunately, soil-residual PPO-inhibiting herbicides remain efficacious in waterhemp populations resistant to PPO-inhibiting herbicides; however, these herbicides should theoretically select for the resistant biotype as herbicide concentrations diminish in the soil. Accordingly, the objectives of this research were twofold: (1) evaluate the efficacy of three PPO-inhibiting herbicides, foliar- and soil-applied, on PPO-resistant (PPO-R) and PPO-susceptible (PPO-S) waterhemp, and (2) investigate the differential effects of PPO-inhibiting herbicides on an R biotype and an S biotype during several discrete developmental events relevant to soil–residual herbicide activity (i.e., radicle protrusion, radicle elongation, and waterhemp emergence). Greenhouse and growth chamber experiments indicated that the R biotype was least sensitive to the diphenylether herbicide fomesafen, followed by sulfentrazone and flumioxazin; however, fomesafen plus s-metolachlor improved soil-residual efficacy over fomesafen alone. Growth stage considerably influenced the R : S ratio, decreasing from 38× to 3.4×, when comparing ratios generated from foliar applications and soil-residual applications measuring radicle protrusion, respectively. Overall, this research supports the use of full soil-residual herbicide rates, reinforcing the importance of best management practices to manage the spread of herbicide resistance.
A segment of the debate surrounding the commercialization and use of glyphosate-resistant (GR) crops focuses on the theory that the implementation of these traits is an extension of the intensification of agriculture that will further erode the biodiversity of agricultural landscapes. A large field-scale study was initiated in 2006 in the United States on 156 different field sites with a minimum 3-yr history of GR-corn, -cotton or -soybean in the cropping system. The impact of cropping system, crop rotation, frequency of using the GR crop trait, and several categorical variables on seedbank weed population density and diversity was analyzed. The parameters of total weed population density of all species in the seedbank, species richness, Shannon's H′ and evenness were not affected by any management treatment. The similarity between the seedbank and aboveground weed community was more strongly related to location than management; previous year's crops and cropping systems were also important while GR trait rotation was not. The composition of the weed flora was more strongly related to location (geography) than any other parameter. The diversity of weed flora in agricultural sites with a history of GR crop production can be influenced by several factors relating to the specific method in which the GR trait is integrated (cropping system, crop rotation, GR trait rotation), the specific weed species, and the geographical location. Continuous GR crop, compared to fields with other cropping systems, only had greater species diversity (species richness) of some life forms, i.e., biennials, winter annuals, and prostrate weeds. Overall diversity was related to geography and not cropping system. These results justify further research to clarify the complexities of crops grown with herbicide-resistance traits to provide a more complete characterization of their culture and local adaptation to the weed seedbank.