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In recent years, soybean acreage has increased significantly in western Canada. One of the challenges associated with growing soybean in western Canada is the control of volunteer glyphosate-resistant (GR) canola, because most soybean cultivars are also glyphosate resistant. The objective of this research was to determine the impact of soybean seeding rate and planting date on competition with volunteer canola. We also attempted to determine how high seeding rate could be raised while still being economically feasible for producers. Soybean was seeded at five different seeding rates (targeted 10, 20, 40, 80, and 160 plants m−2) and three planting dates (targeted mid-May, late May, and early June) at four sites across western Canada in 2014 and 2015. Soybean yield consistently increased with higher seeding rates, whereas volunteer canola biomass decreased. Planting date generally produced variable results across site-years. An economic analysis determined that the optimal rate was 40 to 60 plants m−2, depending on market price, and the optimal planting date range was from May 20 to June 1.
Iron deficiency is common in pregnant and lactating women and is associated with reduced cognitive development of the offspring. Since iron affects lipid metabolism, the availability of fatty acids, particularly the polyunsaturated fatty acids required for early neural development, was investigated in the offspring of female rats fed iron-deficient diets during gestation and lactation. Subsequent to the dams giving birth, one group of iron-deficient dams was recuperated by feeding an iron-replete diet. Dams and neonates were killed on postnatal days 1, 3 and 10, and the fatty acid composition of brain and stomach contents was assessed by gas chromatography. Changes in the fatty acid profile on day 3 became more pronounced on day 10 with a decrease in the proportion of saturated fatty acids and a compensatory increase in monounsaturated fatty acids. Long-chain polyunsaturated fatty acids in the n-6 family were reduced, but there was no change in the n-3 family. The fatty acid profiles of neonatal brain and stomach contents were similar, suggesting that the change in milk composition may be related to the changes in the neonatal brain. When the dams were fed an iron-sufficient diet at birth, the effects of iron deficiency on the fatty acid composition of lipids in both dam’s milk and neonates’ brains were reduced. This study showed an interaction between maternal iron status and fatty acid composition of the offspring’s brain and suggests that these effects can be reduced by iron repletion of the dam’s diet at birth.
TwinsUK is the largest cohort of community-dwelling adult twins in the UK. The registry comprises over 14,000 volunteer twins (14,838 including mixed, single and triplets); it is predominantly female (82%) and middle-aged (mean age 59). In addition, over 1800 parents and siblings of twins are registered volunteers. During the last 27 years, TwinsUK has collected numerous questionnaire responses, physical/cognitive measures and biological measures on over 8500 subjects. Data were collected alongside four comprehensive phenotyping clinical visits to the Department of Twin Research and Genetic Epidemiology, King’s College London. Such collection methods have resulted in very detailed longitudinal clinical, biochemical, behavioral, dietary and socioeconomic cohort characterization; it provides a multidisciplinary platform for the study of complex disease during the adult life course, including the process of healthy aging. The major strength of TwinsUK is the availability of several ‘omic’ technologies for a range of sample types from participants, which includes genomewide scans of single-nucleotide variants, next-generation sequencing, metabolomic profiles, microbiomics, exome sequencing, epigenetic markers, gene expression arrays, RNA sequencing and telomere length measures. TwinsUK facilitates and actively encourages sharing the ‘TwinsUK’ resource with the scientific community — interested researchers may request data via the TwinsUK website (http://twinsuk.ac.uk/resources-for-researchers/access-our-data/) for their own use or future collaboration with the study team. In addition, further cohort data collection is planned via the Wellcome Open Research gateway (https://wellcomeopenresearch.org/gateways). The current article presents an up-to-date report on the application of technological advances, new study procedures in the cohort and future direction of TwinsUK.
Foodborne salmonellosis causes approximately 1 million illnesses annually in the United States. In the summer of 2017, we investigated four multistate outbreaks of Salmonella infections associated with Maradol papayas imported from four Mexican farms. PulseNet initially identified a cluster of Salmonella Kiambu infections in June 2017, and early interviews identified papayas as an exposure of interest. Investigators from Maryland, Virginia and Food and Drug Administration (FDA) collected papayas for testing. Several strains of Salmonella were isolated from papayas sourced from Mexican Farm A, including Salmonella Agona, Gaminara, Kiambu, Thompson and Senftenberg. Traceback from two points of service associated with illness sub-clusters in two states identified Farm A as a common source of papayas, and three voluntary recalls of Farm A papayas were issued. FDA sampling isolated four additional Salmonella strains from papayas sourced from Mexican Farms B, C and D. In total, four outbreaks were identified, resulting in 244 cases with illness onset dates from 20 December 2016 to 20 September 2017. The sampling of papayas and the collaborative work of investigative partners were instrumental in identifying the source of these outbreaks and preventing additional illnesses. Evaluating epidemiological, laboratory and traceback evidence together during investigations is critical to solving and stopping outbreaks.
We describe the design and deployment of GREENBURST, a commensal Fast Radio Burst (FRB) search system at the Green Bank Telescope. GREENBURST uses the dedicated L-band receiver tap to search over the 960–1 920 MHz frequency range for pulses with dispersion measures out to
. Due to its unique design, GREENBURST is capable of conducting searches for FRBs when the L-band receiver is not being used for scheduled observing. This makes it a sensitive single pixel detector capable of reaching deeper in the radio sky. While single pulses from Galactic pulsars and rotating radio transients will be detectable in our observations, and will form part of the database we archive, the primary goal is to detect and study FRBs. Based on recent determinations of the all-sky rate, we predict that the system will detect approximately one FRB for every 2–3 months of continuous operation. The high sensitivity of GREENBURST means that it will also be able to probe the slope of the FRB fluence distribution, which is currently uncertain in this observing band.
Recent years have seen an exponential increase in the variety of healthcare data captured across numerous sources. However, mechanisms to leverage these data sources to support scientific investigation have remained limited. In 2013 the Pediatric Heart Network (PHN), funded by the National Heart, Lung, and Blood Institute, developed the Integrated CARdiac Data and Outcomes (iCARD) Collaborative with the goals of leveraging available data sources to aid in efficiently planning and conducting PHN studies; supporting integration of PHN data with other sources to foster novel research otherwise not possible; and mentoring young investigators in these areas. This review describes lessons learned through the development of iCARD, initial efforts and scientific output, challenges, and future directions. This information can aid in the use and optimisation of data integration methodologies across other research networks and organisations.
Introduction: Adolescents who present to emergency departments (ED) following intentional injuries present a challenge in terms of ascertaining their intent and risk for future self-injurious or suicidal behaviour. Our ED has seen an 80% increase in visits for mental health issues over the past ten years. As usage of our Emergency Mental Health and Addictions Services (EMHAS) team continues to rise, it is increasingly important to understand the incidence of NSSI among our youth, explore if NSSI is reported at triage and identify characteristics that may distinguish these adolescents from others presenting for mental health assessment. Methods: This is an exploratory research study using retrospective data. Patients who had an Emergency Mental Health Triage (EMHT) form on their health record from an ED visit between June 1, 2017 and May 31, 2018 were eligible. Trained research assistants, using a structured data collection form in REDCap. abstracted data from the EMHT form, the EMHAS Assessment form, the Assessment of Suicide Risk Inventory and our CHIRPP (Canadian Hospitals Injury Reporting and Prevention Program) database. We calculated kappa values and 95% confidence intervals to describe the extent to which the forms agree with respect to identifying NSSI. We will compare the cohort who reports NSSI with the cohort who does not report NSSI using chi-square statistics depending. We will use descriptive statistics to characterize the NSSI patients. Results: During the one-year study period 955 patients had an EMHT form completed. In preliminary analysis 558 (58.4%) reported a history of NSSI. Patients reported NSSI on both the EMHT form and the EMHAS assessment form 64.7% of the time (kappa 0.56) indicating moderate agreement. In patients with NSSI, 9.5% of patients reported it only at triage and 25.8% of patients reported it only during their EMHAS assessment. Between group comparisons and descriptive analysis is underway. Conclusion: More than half of youth triaged with an emergency mental health complaint in our ED reported a history of NSSI. Screening at triage was moderately effective in identifying adolescents with NSSI compared to an in-depth assessment by the mental health team. Further research is needed to clarify how NSSI relates to risk for suicide.
Research showing that risk for schizophrenia, bipolar disorder with psychosis, and other psychosis-spectrum diagnoses in adulthood is multidetermined has underscored the necessity of studying the additive and interactive factors in childhood that precede and predict future disorders. In this study, risk for the development of psychosis-spectrum disorders was examined in a 2-generation, 30-year prospective longitudinal study of 3,905 urban families against a sociocultural backdrop of changing economic and social conditions. Peer nominations of aggression, withdrawal, and likeability and national census information on neighborhood-level socioeconomic disadvantage in childhood, as well as changes in neighborhood socioeconomic conditions over the lifespan, were examined as predictors of diagnoses of schizophrenia, bipolar disorder, and other psychosis-spectrum disorders in adulthood relative to developing only nonpsychotic disorders or no psychiatric disorders. Individuals who were both highly aggressive and highly withdrawn were at greater risk for other psychosis-spectrum diagnoses when they experienced greater neighborhood disadvantage in childhood or worsening neighborhood conditions over maturation. Males who were highly aggressive but low on withdrawal were at greater risk for schizophrenia diagnoses. Childhood neighborhood disadvantage predicted both schizophrenia and bipolar diagnoses, regardless of childhood social behavior. Results provided strong support for multiple-domain models of psychopathology, and suggest that universal preventive interventions and social policies aimed at improving neighborhood conditions may be particularly important for decreasing the prevalence of psychosis-spectrum diagnoses in the future.
Sample preparation techniques for radiocarbon analysis of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) in freshwater, as well as CO2 and CH4 in gas mixtures are presented. Focused efforts have been on developing a robust and low-background wet oxidation extraction method for DOC in freshwater, following routine methods developed for stable carbon isotope analysis and adapted for radiocarbon (14C) analysis. DIC (by acidification) and DOC (by wet oxidation) are converted to CO2 in pre-baked septum-fitted borosilicate bottles, where the resulting CO2 is extracted from the dissolved and headspace portions on a low-flow He-carrier flow-through system interfaced to a vacuum extraction line. A peripheral CH4 extraction line interfaces to the flow line to separate CH4 from environmental samples following the methods of Pack et al. 2015. High sample throughput and low blanks are achievable with this method. DIC and DOC blanks are consistently <0.7 pMC, while CO2 and CH4 blanks are typically <0.1 pMC.
A modern pedagogical treatment of the latest industry trends in rocket propulsion, developed from the authors' extensive experience in both industry and academia. Students are guided along a step-by-step journey through modern rocket propulsion, beginning with the historical context and an introduction to top-level performance measures, and progressing on to in-depth discussions of the chemical aspects of fluid flow combustion thermochemistry and chemical equilibrium, solid, liquid, and hybrid rocket propellants, mission requirements, and an overview of electric propulsion. With a wealth of homework problems (and a solutions manual for instructors online), real-life case studies and examples throughout, and an appendix detailing key numerical methods and links to additional online resources, this is a must-have guide for senior and first year graduate students looking to gain a thorough understanding of the topic along with practical tools that can be applied in industry.