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Potential effectiveness of harvest weed seed control (HWSC) systems depends upon seed shatter of the target weed species at crop maturity, enabling its collection and processing at crop harvest. However, seed retention likely is influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter phenology in thirteen economically important broadleaf weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after physiological maturity at multiple sites spread across fourteen states in the southern, northern, and mid-Atlantic U.S. Greater proportions of seeds were retained by weeds in southern latitudes and shatter rate increased at northern latitudes. Amaranthus species seed shatter was low (0 to 2%), whereas shatter varied widely in common ragweed (Ambrosia artemisiifolia L.) (2 to 90%) over the weeks following soybean physiological maturity. Overall, the broadleaf species studied shattered less than ten percent of their seeds by soybean harvest. Our results suggest that some of the broadleaf species with greater seed retention rates in the weeks following soybean physiological maturity may be good candidates for HWSC.
Seed shatter is an important weediness trait on which the efficacy of harvest weed seed control (HWSC) depends. The level of seed shatter in a species is likely influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter of eight economically important grass weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after maturity at multiple sites spread across eleven states in the southern, northern, and mid-Atlantic U.S. From soybean maturity to four weeks after maturity, cumulative percent seed shatter was lowest in the southern U.S. regions and increased as the states moved further north. At soybean maturity, the percent of seed shatter ranged from 1 to 70%. That range had shifted to 5 to 100% (mean: 42%) by 25 days after soybean maturity. There were considerable differences in seed shatter onset and rate of progression between sites and years in some species that could impact their susceptibility to HWSC. Our results suggest that many summer annual grass species are likely not ideal candidates for HWSC, although HWSC could substantially reduce their seed output at during certain years.
Background: The burden of C. difficile infection (CDI) on healthcare facilities is well recognized. However, studies focusing on inpatient settings, in addition to ascertainment bias in general, have led to a paucity of data on the true burden of CDI across whole healthcare economies. Methods: Sites testing both inpatient and community samples were recruited from 12 European countries (1 site per 3 million population). On 2 selected days, all diarrheal fecal samples (regardless of tests requested) were sent to the European Coordinating Laboratory (ECL) for C. difficile toxin testing and culture. The CDI results and tests not requested at each submitting site were compared with the ECL results to determine the number of missed CDIs. Contemporaneous C. difficile isolates from food and animal sources were collected. All isolates underwent PCR ribotyping and toxinotyping; prevalences of ribotypes among regions of Europe and reservoir settings were compared. Results: Overall, 3,163 diarrheal fecal samples were received from 119 sites. The burden of CDI varied by country (positivity rates, 0–15.8%) and by European region; the highest positivity rate in Eastern Europe was 13.1%. The testing and positivity rates in community samples were 29.6% and 1.4% vs 74.9% and 5.0% in hospital samples; 16% and 55% of samples positive for CDI at ECL were not diagnosed in hospitals and the community. The most common C. difficile ribotypes from hospital samples were 027 (11%), 181 (12%), and 014 (8%), although prevalence varied by country. The highest prevalence of toxinotype IIIb (ribotypes 027, 181, and 176) was seen in Eastern Europe (55% of all isolates), which also had the lowest testing rate. For hospital samples, the proportion of toxinotype IIIb was inversely related to the testing rate (r = −0.79) (Fig. 1). The most common ribotypes from food sources were 078 (23%) and 126 (13%) (toxinotype V), and most common ribotypes from community samples were 078 (9%) and 039 (9%). Overall, 106 different ribotypes were identified: 25 in both the hospital and community and 16 in the hospital, community, and food chain. Conclusions: The diagnosed burden of CDI varies markedly among countries in both hospital and community settings. Reduced sampling/testing in Eastern Europe is inversely related to the proportion of toxinotype IIIb strains identified, suggesting that lack of suspicion leads to underdiagnosis and outbreaks of infection. The proportion of missed CDIs in the community was ~3.5× higher than in hospitals, indicating major underrecognition in the former setting. There were marked differences in ribotypes in different reservoir settings, emphasizing the complex epidemiology of C. difficile.
Funding: Proprietary organization: COMBACTE-CDI is an EU funded (Horizon2020) consortium of academic and EFPIA partners (bioMerieux, GSK, Sanofi Pasteur, Astra Zeneca, Pfizer, Da Volterra) with additional Funding: from the EFPIA partners.
Disclosures: Submitter: Kerrie Davies; the work presented is funded via the EU and EFPIA (commercial) partners in a consortium.
The inclusion of students with autism spectrum disorder (ASD) is increasing, but there have been no longitudinal studies of included students in Australia. Interview data reported in this study concern primary school children with ASD enrolled in mainstream classes in South Australia and New South Wales, Australia. In order to examine perceived facilitators and barriers to inclusion, parents, teachers, and principals were asked to comment on the facilitators and barriers to inclusion relevant to each child. Data are reported about 60 students, comprising a total of 305 parent interviews, 208 teacher interviews, and 227 principal interviews collected at 6-monthly intervals over 3.5 years. The most commonly mentioned facilitator was teacher practices. The most commonly mentioned barrier was intrinsic student factors. Other factors not directly controllable by school staff, such as resource limitations, were also commonly identified by principals and teachers. Parents were more likely to mention school- or teacher-related barriers. Many of the current findings were consistent with previous studies but some differences were noted, including limited reporting of sensory issues and bullying as barriers. There was little change in the pattern of facilitators and barriers identified by respondents over time. A number of implications for practice and directions for future research are discussed.
Life course research embraces the complexity of health and disease development, tackling the extensive interactions between genetics and environment. This interdisciplinary blueprint, or theoretical framework, offers a structure for research ideas and specifies relationships between related factors. Traditionally, methodological approaches attempt to reduce the complexity of these dynamic interactions and decompose health into component parts, ignoring the complex reciprocal interaction of factors that shape health over time. New methods that match the epistemological foundation of the life course framework are needed to fully explore adaptive, multilevel, and reciprocal interactions between individuals and their environment. The focus of this article is to (1) delineate the differences between lifespan and life course research, (2) articulate the importance of complex systems science as a methodological framework in the life course research toolbox to guide our research questions, (3) raise key questions that can be asked within the clinical and translational science domain utilizing this framework, and (4) provide recommendations for life course research implementation, charting the way forward. Recent advances in computational analytics, computer science, and data collection could be used to approximate, measure, and analyze the intertwining and dynamic nature of genetic and environmental factors involved in health development.
UK Biobank is a well-characterised cohort of over 500 000 participants including genetics, environmental data and imaging. An online mental health questionnaire was designed for UK Biobank participants to expand its potential.
Describe the development, implementation and results of this questionnaire.
An expert working group designed the questionnaire, using established measures where possible, and consulting a patient group. Operational criteria were agreed for defining likely disorder and risk states, including lifetime depression, mania/hypomania, generalised anxiety disorder, unusual experiences and self-harm, and current post-traumatic stress and hazardous/harmful alcohol use.
A total of 157 366 completed online questionnaires were available by August 2017. Participants were aged 45–82 (53% were ≥65 years) and 57% women. Comparison of self-reported diagnosed mental disorder with a contemporary study shows a similar prevalence, despite respondents being of higher average socioeconomic status. Lifetime depression was a common finding, with 24% (37 434) of participants meeting criteria and current hazardous/harmful alcohol use criteria were met by 21% (32 602), whereas other criteria were met by less than 8% of the participants. There was extensive comorbidity among the syndromes. Mental disorders were associated with a high neuroticism score, adverse life events and long-term illness; addiction and bipolar affective disorder in particular were associated with measures of deprivation.
The UK Biobank questionnaire represents a very large mental health survey in itself, and the results presented here show high face validity, although caution is needed because of selection bias. Built into UK Biobank, these data intersect with other health data to offer unparalleled potential for crosscutting biomedical research involving mental health.
Healthcare personnel (HCP) were recruited to provide serum samples, which were tested for antibodies against Ebola or Lassa virus to evaluate for asymptomatic seroconversion.
From 2014 to 2016, 4 patients with Ebola virus disease (EVD) and 1 patient with Lassa fever (LF) were treated in the Serious Communicable Diseases Unit (SCDU) at Emory University Hospital. Strict infection control and clinical biosafety practices were implemented to prevent nosocomial transmission of EVD or LF to HCP.
All personnel who entered the SCDU who were required to measure their temperatures and complete a symptom questionnaire twice daily were eligible.
No employee developed symptomatic EVD or LF. EVD and LF antibody studies were performed on sera samples from 42 HCP. The 6 participants who had received investigational vaccination with a chimpanzee adenovirus type 3 vectored Ebola glycoprotein vaccine had high antibody titers to Ebola glycoprotein, but none had a response to Ebola nucleoprotein or VP40, or a response to LF antigens.
Patients infected with filoviruses and arenaviruses can be managed successfully without causing occupation-related symptomatic or asymptomatic infections. Meticulous attention to infection control and clinical biosafety practices by highly motivated, trained staff is critical to the safe care of patients with an infection from a special pathogen.
We apply deep kernel learning (DKL), which can be viewed as a combination of a Gaussian process (GP) and a deep neural network (DNN), to compression ignition engine emissions and compare its performance to a selection of other surrogate models on the same dataset. Surrogate models are a class of computationally cheaper alternatives to physics-based models. High-dimensional model representation (HDMR) is also briefly discussed and acts as a benchmark model for comparison. We apply the considered methods to a dataset, which was obtained from a compression ignition engine and includes as outputs soot and NOx emissions as functions of 14 engine operating condition variables. We combine a quasi-random global search with a conventional grid-optimization method in order to identify suitable values for several DKL hyperparameters, which include network architecture, kernel, and learning parameters. The performance of DKL, HDMR, plain GPs, and plain DNNs is compared in terms of the root mean squared error (RMSE) of the predictions as well as computational expense of training and evaluation. It is shown that DKL performs best in terms of RMSE in the predictions whilst maintaining the computational cost at a reasonable level, and DKL predictions are in good agreement with the experimental emissions data.
Crack initiation in zirconium alloys is an important issue for the safety of water-cooled fission reactors. Zirconium hydrides that precipitate in service are potential crack nucleation sites. In this work, the deformation and cracking of zirconium hydrides was studied during room temperature deformation of a Zircaloy-4 tensile sample up to fracture. The sample contained a hydrogen concentration of 100 ± 20 ppm. The main aims of this study were to better understand the mechanisms behind the hydride fracture in a polycrystalline matrix, and to identify at which point in the deformation of the Zr matrix the first hydrides break. Cracks thus nucleated may coalesce and propagate through the hydrided Zr-alloy. Scanning electron microscopy (SEM) images of a number of hydrides, both intergranular and intragranular, were taken at discrete increments of deformation during an interrupted tensile test. The results show that cracks in hydrides tend to always occur normal to the applied load, signalling the importance of the external stress. However, evidence is also provided to support the hypothesis that internal stresses generated by microstructural constraints may lead to the fracture of some intergranular hydrides.
An ever-increasing number of laboratory facilities are enabling in situ spectral reflectance measurements of materials under conditions relevant to all the bodies in the Solar System, from Mercury to Pluto and beyond. Results derived from these facilities demonstrate that exposure of different materials to various planetary surface conditions can provide insights into the endogenic and exogenic processes that operate to modify their surface spectra, and their relative importance. Temperature, surface atmospheric pressure, atmospheric composition, radiation environment, and exposure to the space environment have all been shown to measurably affect reflectance and emittance spectra of a wide range of materials. Planetary surfaces are dynamic environments, and as our ability to reproduce a wider range of planetary surface conditions improves, so will our ability to better determine the surface composition of these bodies, and by extension, their geologic history.
Major depressive disorder and neuroticism (Neu) share a large genetic basis. We sought to determine whether this shared basis could be decomposed to identify genetic factors that are specific to depression.
We analysed summary statistics from genome-wide association studies (GWAS) of depression (from the Psychiatric Genomics Consortium, 23andMe and UK Biobank) and compared them with GWAS of Neu (from UK Biobank). First, we used a pairwise GWAS analysis to classify variants as associated with only depression, with only Neu or with both. Second, we estimated partial genetic correlations to test whether the depression's genetic link with other phenotypes was explained by shared overlap with Neu.
We found evidence that most genomic regions (25/37) associated with depression are likely to be shared with Neu. The overlapping common genetic variance of depression and Neu was genetically correlated primarily with psychiatric disorders. We found that the genetic contributions to depression, that were not shared with Neu, were positively correlated with metabolic phenotypes and cardiovascular disease, and negatively correlated with the personality trait conscientiousness. After removing shared genetic overlap with Neu, depression still had a specific association with schizophrenia, bipolar disorder, coronary artery disease and age of first birth. Independent of depression, Neu had specific genetic correlates in ulcerative colitis, pubertal growth, anorexia and education.
Our findings demonstrate that, while genetic risk factors for depression are largely shared with Neu, there are also non-Neu-related features of depression that may be useful for further patient or phenotypic stratification.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Intertidal biofilms are a diverse mixture of bacteria, algae as well as sporelings of macroalgae embedded in a polysaccharid matrix. As the primary colonisers of newly formed surfaces, biofilms undergo a succession of different microbe assemblage until the mature state is reached. A biofilm can act as primary producers and as such recycle nutrients in a habitat. It will influence macrobiota by providing a food source or sending out cues to settlers. Biofilms themselves will be controlled by these settlers. This interaction between bottom-up and top-down plays a crucial part for the functioning of the rocky shore ecosystems. However, the diversity of biolfilms as well as it nature to react quickly to environmental changes makes identification and quantification of the individual compounds a difficult task. Subsequently, the understanding of biofilms in general and intertidal, rocky shore microbe assemblages has always tied to techniques and methods available at the time of study. This chapter focusses on the techniques that have greatly contributed to increasing knowledge of biofilms and discusses their findings. Nonetheless, newly developed methods promise to further this knowledge of the ecological role of biofilms on rocky coastlines.
Infants with CHD often experience growth failure. Ensuring optimal growth before surgery is associated with improved outcomes and has emerged as a significant cause of parental stress. Parents have reported a perceived lack of accessible feeding information for infants with CHD. To address this gap, the aim of this study was to develop feeding information to better support parents.
Materials and methods:
A search for existing material on six electronic databases and an internet search for unpublished (grey) literature on feeding information for infants with CHD were carried out. Following the development of feeding information, semi-structured interview(s) with parents/health-care professionals were completed, focusing on whether the information was easy to understand, relevant, provided sufficient information around feeding/feeding difficulties, and whether there were any information gaps. Iterative changes were made to the information following each interview. The process was completed until thematic saturation was achieved.
A total of 23 unique articles were identified of which 5 studies were included. From the grey literature, four web pages were reviewed. A total of 22 parents and 25 health-care professionals were interviewed. All parents/health-care professionals felt that the feeding information developed provided sufficient information; however, many wanted information on how to introduce complementary food, particularly if weaning was delayed.
This study describes the development of feeding information for infants with CHD. From parent interviews, gaps identified focused on the introduction of complementary foods and uncertainty regarding the feeding journey beyond surgery.
There are several types of absolute constructions (acs) in English. Among these, this article investigates the so-called what-with ac, which has not received much attention in the study of English grammar. This article considers the grammatical properties of the construction from a synchronic as well as a diachronic perspective, using much more representative and robust corpora than previous studies. Based on corpus data drawn from historical corpora such as COHA (Corpus of Historical American English, 400 million words), the article addresses questions about changes in the construction's syntactic, semantic and pragmatic properties. In addition, the article provides a Construction Grammar perspective, which supports previous research in arguing that the construction is undergoing the processes of grammatical constructionalization.
Performing an extended Focused Assessment with Sonography in Trauma (eFAST) exam is common practice in the initial assessment of trauma patients. The objective of this study was to systematically review the published literature on diagnostic accuracy of all components of the eFAST exam.
We searched Medline and Embase from inception through October 2018, for diagnostic studies examining the sensitivity and specificity of the eFAST exam. After removal of duplicates, 767 records remained for screening, of which 119 underwent full text review. Meta-DiSc™ software was used to create pooled sensitivities and specificities for included studies. Study quality was assessed using the Quality in Prognostic Studies (QUADAS-2) tool.
Seventy-five studies representing 24,350 patients satisfied our selection criteria. Studies were published between 1989 and 2017. Pooled sensitivities and specificities were calculated for the detection of pneumothorax (69% and 99% respectively), pericardial effusion (91% and 94% respectively), and intra-abdominal free fluid (74% and 98% respectively). Sub-group analysis was completed for detection of intra-abdominal free fluid in hypotensive (sensitivity 74% and specificity 95%), adult normotensive (sensitivity 76% and specificity 98%) and pediatric patients (sensitivity 71% and specificity 95%).
Our systematic review and meta-analysis suggests that e-FAST is a useful bedside tool for ruling in pneumothorax, pericardial effusion, and intra-abdominal free fluid in the trauma setting. Its usefulness as a rule-out tool is not supported by these results.
Filarial nematodes possess glutathione transferases (GSTs), ubiquitous enzymes with the potential to detoxify xenobiotic and endogenous substrates, and modulate the host immune system, which may aid worm infection establishment, maintenance and survival in the host. Here we have identified and characterized a σ class glycosylated GST (OoGST1), from the cattle-infective filarial nematode Onchocerca ochengi, which is homologous (99% amino acid identity) with an immunodominant GST and potential vaccine candidate from the human parasite, O. volvulus, (OvGST1b). Onchocerca ochengi native GSTs were purified using a two-step affinity chromatography approach, resolved by 2D and 1D SDS-PAGE and subjected to enzymic deglycosylation revealing the existence of at least four glycoforms. A combination of lectin-blotting and mass spectrometry (MS) analyses of the released N-glycans indicated that OoGST1 contained mainly oligomannose Man5GlcNAc2 structure, but also hybrid- and larger oligommanose-type glycans in a lower proportion. Furthermore, purified OoGST1 showed prostaglandin synthase activity as confirmed by Liquid Chromatography (LC)/MS following a coupled-enzyme assay. This is only the second reported and characterized glycosylated GST and our study highlights its potential role in host-parasite interactions and use in the study of human onchocerciasis.
This study tested whether the association between interparental conflict and adolescent externalizing symptoms was moderated by a polygenic composite indexing low dopamine activity (i.e., 7-repeat allele of DRD4; Val alleles of COMT; 10-repeat variants of DAT1) in a sample of seventh-grade adolescents (Mean age = 13.0 years) and their parents. Using a longitudinal, autoregressive design, observational assessments of interparental conflict at Wave 1 predicted increases in a multi-informant measurement of youth externalizing symptoms 2 years later at Wave 3 only for children who were high on the hypodopaminergic composite. Moderation was expressed in a “for better” or “for worse” form hypothesized by differential susceptibility theory. Thus, children high on the dopaminergic composite experienced more externalizing problems than their peers when faced with more destructive conflicts but also fewer externalizing problems when exposed to more constructive interparental conflicts. Mediated moderation findings indicated that adolescent reports of their emotional insecurity in the interparental relationship partially explained the greater genetic susceptibility experienced by these children. More specifically, the dopamine composite moderated the association between Wave 1 interparental conflict and emotional insecurity 1 year later at Wave 2 in the same “for better” or “for worse” pattern as externalizing symptoms. Adolescent insecurity at Wave 2, in turn, predicted their greater externalizing symptoms 1 year later at Wave 3. Post hoc analyses further revealed that the 7-repeat allele of the dopamine receptor D4 (DRD4) gene was the primary source of plasticity in the polygenic composite. Results are discussed as to how they advance process-oriented Gene x Environment models of emotion regulation.
Globular clusters (GCs) display anomalous light-elements abundances (HeCNONaMgAl), resembling the yields of hot-hydrogen burning, but there is no consensus yet on the origin of these ubiquitous multiple populations. We present a model in which a super-massive star (SMS, ≳103 M⊙) forms via stellar collisions during GC formation and pollutes the intra-cluster medium. The growth of the SMS finds a balance with the wind mass loss rate, such that the SMS can produce a significant fraction of the total GC mass in processed material, thereby overcoming the so-called mass-budget problem that plagues other models. Because of continuous rejuvenation, the SMS acts as a ‘conveyer-belt’ of hot-hydrogen burning yields with (relatively) low He abundances, in agreement with empirical constraints. Additionally, the amount of processed material per unit of GC mass correlates with GC mass, addressing the specific mass budget problem. We discuss uncertainties and tests of this new self-enrichment scenario.