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Establishment of alfalfa by interseeding into corn planted for silage can enhance crop productivity but weed management is a challenge to adoption. Although a glyphosate-based herbicide program could be a simple and effective approach, concerns about herbicide resistance and limitations in available alfalfa varieties exist. Field experiments were conducted to compare the efficacy and selectivity of preemergence (PRE), postemergence (POST) and PRE followed by POST herbicide programs to a glyphosate only strategy when interseeding alfalfa into corn. Experiment 1 compared PRE applications of acetochlor, mesotrione, S-metalochlor, metribuzin, and flumetsulam, and found both rates of acetochlor and metribuzin, and S-metalochlor at 1.1 kg ha-1 were the most effective and selective PRE herbicides 4 weeks after treatment (WAT), but each resulted in greater overall weed cover than glyphosate by 8 WAT. Experiment 2 evaluated POST applications at early and late timings of bentazon, bromoxynil, 2,4-DB, and mesotrione. Several POST herbicides exhibited similar effectiveness and selectivity as glyphosate including early applications of bromoxynil (0.14 kg ha-1) and 2,4-DB (0.84 or 1.68 kg ha-1), as well as late applications of bromoxynil (0.42 kg ha-1), 2,4-DB (0.84 kg ha-1) and mesotrione (0.05 or 0.11 kg ha-1). A third experiment compared applications of acetochlor PRE, bromoxynil POST, and the combination of acetochlor PRE with bromoxynil POST. All treatments were effective and safe for use in this interseeded system, although interseeded alfalfa provided 65-70% weed suppression in corn planted for silage without any herbicide. Herbicide treatments had no observable impacts on corn and alfalfa yields so weed management was likely of limited economic importance. However, weed competitiveness can vary based on several different factors including weed species, density, and site-specific factors, and so further investigations under different environments and conditions are needed.
Antarctica's ice shelves modulate the grounded ice flow, and weakening of ice shelves due to climate forcing will decrease their ‘buttressing’ effect, causing a response in the grounded ice. While the processes governing ice-shelf weakening are complex, uncertainties in the response of the grounded ice sheet are also difficult to assess. The Antarctic BUttressing Model Intercomparison Project (ABUMIP) compares ice-sheet model responses to decrease in buttressing by investigating the ‘end-member’ scenario of total and sustained loss of ice shelves. Although unrealistic, this scenario enables gauging the sensitivity of an ensemble of 15 ice-sheet models to a total loss of buttressing, hence exhibiting the full potential of marine ice-sheet instability. All models predict that this scenario leads to multi-metre (1–12 m) sea-level rise over 500 years from present day. West Antarctic ice sheet collapse alone leads to a 1.91–5.08 m sea-level rise due to the marine ice-sheet instability. Mass loss rates are a strong function of the sliding/friction law, with plastic laws cause a further destabilization of the Aurora and Wilkes Subglacial Basins, East Antarctica. Improvements to marine ice-sheet models have greatly reduced variability between modelled ice-sheet responses to extreme ice-shelf loss, e.g. compared to the SeaRISE assessments.
Prolonged survival of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on environmental surfaces and personal protective equipment may lead to these surfaces transmitting this pathogen to others. We sought to determine the effectiveness of a pulsed-xenon ultraviolet (PX-UV) disinfection system in reducing the load of SARS-CoV-2 on hard surfaces and N95 respirators.
Chamber slides and N95 respirator material were directly inoculated with SARS-CoV-2 and were exposed to different durations of PX-UV.
For hard surfaces, disinfection for 1, 2, and 5 minutes resulted in 3.53 log10, >4.54 log10, and >4.12 log10 reductions in viral load, respectively. For N95 respirators, disinfection for 5 minutes resulted in >4.79 log10 reduction in viral load. PX-UV significantly reduced SARS-CoV-2 on hard surfaces and N95 respirators.
With the potential to rapidly disinfectant environmental surfaces and N95 respirators, PX-UV devices are a promising technology to reduce environmental and personal protective equipment bioburden and to enhance both healthcare worker and patient safety by reducing the risk of exposure to SARS-CoV-2.
Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
We evaluated the safety and feasibility of high-intensity interval training via a novel telemedicine ergometer (MedBIKE™) in children with Fontan physiology.
The MedBIKE™ is a custom telemedicine ergometer, incorporating a video game platform and live feed of patient video/audio, electrocardiography, pulse oximetry, and power output, for remote medical supervision and modulation of work. There were three study phases: (I) exercise workload comparison between the MedBIKE™ and a standard cardiopulmonary exercise ergometer in 10 healthy adults. (II) In-hospital safety, feasibility, and user experience (via questionnaire) assessment of a MedBIKE™ high-intensity interval training protocol in children with Fontan physiology. (III) Eight-week home-based high-intensity interval trial programme in two participants with Fontan physiology.
There was good agreement in oxygen consumption during graded exercise at matched work rates between the cardiopulmonary exercise ergometer and MedBIKE™ (1.1 ± 0.5 L/minute versus 1.1 ± 0.5 L/minute, p = 0.44). Ten youth with Fontan physiology (11.5 ± 1.8 years old) completed a MedBIKE™ high-intensity interval training session with no adverse events. The participants found the MedBIKE™ to be enjoyable and easy to navigate. In two participants, the 8-week home-based protocol was tolerated well with completion of 23/24 (96%) and 24/24 (100%) of sessions, respectively, and no adverse events across the 47 sessions in total.
The MedBIKE™ resulted in similar physiological responses as compared to a cardiopulmonary exercise test ergometer and the high-intensity interval training protocol was safe, feasible, and enjoyable in youth with Fontan physiology. A randomised-controlled trial of a home-based high-intensity interval training exercise intervention using the MedBIKE™ will next be undertaken.
Little is known about the determinants of community integration (i.e. recovery) for individuals with a history of homelessness, yet such information is essential to develop targeted interventions.
We recruited homeless Veterans with a history of psychotic disorders and evaluated four domains of correlates of community integration: perception, non-social cognition, social cognition, and motivation. Baseline assessments occurred after participants were engaged in supported housing services but before they received housing, and again after 12 months. Ninety-five homeless Veterans with a history of psychosis were assessed at baseline and 53 returned after 12 months. We examined both cross-sectional and longitudinal relationships with 12-month community integration.
The strongest longitudinal association was between a baseline motivational measure and social integration at 12 months. We also observed cross-sectional associations at baseline between motivational measures and community integration, including social, work, and independent living. Cross-lagged panel analyses did not suggest causal associations for the motivational measures. Correlations with perception and non-social cognition were weak. One social cognition measure showed a significant longitudinal correlation with independent living at 12 months that was significant for cross-lagged analysis, consistent with a causal relationship and potential treatment target.
The relatively selective associations for motivational measures differ from what is typically seen in psychosis, in which all domains are associated with community integration. These findings are presented along with a partner paper (Study 2) to compare findings from this study to an independent sample without a history of psychotic disorders to evaluate the consistency in findings regarding community integration across projects.
In an initial study (Study 1), we found that motivation predicted community integration (i.e. functional recovery) 12 months after receiving housing in formerly homeless Veterans with a psychotic disorder. The current study examined whether the same pattern would be found in a broader, more clinically diverse, homeless Veteran sample without psychosis.
We examined four categories of variables as potential predictors of community integration in non-psychotic Veterans: perception, non-social cognition, social cognition, and motivation at baseline (after participants were engaged in a permanent supported housing program but before receiving housing) and a 12-month follow-up. A total of 82 Veterans had a baseline assessment and 41 returned for testing after 12 months.
The strongest longitudinal association was between an interview-based measure of motivation (the motivation and pleasure subscale from the Clinical Assessment Interview for Negative Symptoms) at baseline and measures of social integration at 12 months. In addition, cross-lagged panel analyses were consistent with a causal influence of general psychiatric symptoms at baseline driving social integration at 12 months, and reduced expressiveness at baseline driving independent living at 12 months, but there were no significant causal associations with measures of motivation.
The findings from this study complement and reinforce those in Veterans with psychosis. Across these two studies, our findings suggest that motivational factors are associated at baseline and at 12 months and are particularly important for understanding and improving community integration in recently-housed Veterans across psychiatric diagnoses.
Emergency Medical Services (EMS) systems have developed protocols for prehospital activation of the cardiac catheterization laboratory for patients with suspected ST-elevation myocardial infarction (STEMI) to decrease first-medical-contact-to-balloon time (FMC2B). The rate of “false positive” prehospital activations is high. In order to decrease this rate and expedite care for patients with true STEMI, the American Heart Association (AHA; Dallas, Texas USA) developed the Mission Lifeline PreAct STEMI algorithm, which was implemented in Los Angeles County (LAC; California USA) in 2015. The hypothesis of this study was that implementation of the PreAct algorithm would increase the positive predictive value (PPV) of prehospital activation.
This is an observational pre-/post-study of the effect of the implementation of the PreAct algorithm for patients with suspected STEMI transported to one of five STEMI Receiving Centers (SRCs) within the LAC Regional System. The primary outcome was the PPV of cardiac catheterization laboratory activation for percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The secondary outcome was FMC2B.
A total of 1,877 patients were analyzed for the primary outcome in the pre-intervention period and 405 patients in the post-intervention period. There was an overall decrease in cardiac catheterization laboratory activations, from 67% in the pre-intervention period to 49% in the post-intervention period (95% CI for the difference, -14% to -22%). The overall rate of cardiac catheterization declined in post-intervention period as compared the pre-intervention period, from 34% to 30% (95% CI, for the difference -7.6% to 0.4%), but actually increased for subjects who had activation (48% versus 58%; 95% CI, 4.6%-15.0%). Implementation of the PreAct algorithm was associated with an increase in the PPV of activation for PCI or CABG from 37.9% to 48.6%. The overall odds ratio (OR) associated with the intervention was 1.4 (95% CI, 1.1-1.8). The effect of the intervention was to decrease variability between medical centers. There was no associated change in average FMC2B.
The implementation of the PreAct algorithm in the LAC EMS system was associated with an overall increase in the PPV of cardiac catheterization laboratory activation.
Dual energy X-ray absorptiometry (DEXA) is an imaging modality that has been used to predict the computed tomography (CT)-determined carcass composition of multiple species, including sheep and pigs, with minimal inaccuracies, using medical grade DEXA scanners. An online DEXA scanner in an Australian abattoir has shown that a high level of precision can be achieved when predicting lamb carcass composition in real time. This study investigated the accuracy of that same online DEXA when predicting fat and lean percentages as determined by CT over a wide range of phenotypic and genotypic variables across 454 lambs over 6 kill groups and contrasted these results against the current Australian industry standard of grade-rule (GR) measurements to grade carcasses. Lamb carcasses were DEXA scanned and then CT scanned to determine CT Fat % and CT Lean %. All phenotypic traits and genotypic information, including Australian Sheep Breeding Values, were recorded for each carcass. Residuals of the DEXA predicted CT Fat % and Lean %, and the actual CT Fat % and Lean % were calculated and tested against all phenotypic and genotypic variables. Excellent overall precision was recorded when predicting CT Fat % (R2 = 0.91, RMSE = 1.19%). Small biases present for sire breed, sire type, dam breed, hot carcass weight and c-site eye muscle area could be explained by a regression paradox; however, biases among kill group (−0.73% to 1.01% for CT Fat %, −1.48% to 0.76% for CT Lean %) and the Merino sire type (0.36% for CT Fat %, −0.73% for CT Lean %) could not be explained by this effect. Over the large range of phenotypic and genotypic variation, there was excellent precision when predicting CT Fat % and CT Lean % by an online DEXA, with only minor biases, showing superiority to the existing Australian standard of GR measurements.
Addition of fats to the diets of ruminants has long been known to result in a reduction in enteric methane emissions. Tannins have also been used to reduce methane emissions but with mixed success. However, the effect of feeding fat in combination with tannin is unknown. Eight ruminally cannulated Holstein-Friesian cows were fed four diets in a double Latin-square, full crossover sequence. The treatments were 800 ml/day of water (CON), 800 g/day of cottonseed oil, 400 g/day of tannin, and 800 g/day of cottonseed oil and 400 g/day of tannin in combination (fat- and tannin-supplemented diet). Methane emissions were measured using open-circuit respiration chambers. Intake of basal diets was not different between treatments. Cows fed cottonseed oil had greater milk yield (34.9 kg/day) than those fed CON (32.3 kg/day), but the reduced concentration of milk fat meant there was no difference in energy-corrected milk between treatments. Methane yield was reduced when either cottonseed oil (14%) or tannin (11%) was added directly to the rumen, and their effect was additive when given in combination (20% reduction). The mechanism of the anti-methanogenic effect remains unclear but both fat and tannin appear to cause a reduction in fermentation in general rather than cause a change in the type of fermentation.
Neurocognitive and functional neuroimaging studies point to frontal lobe abnormalities in schizophrenia. Molecular and behavioural genetic studies suggest that the frontal lobe is under significant genetic influence. We carried out structural magnetic resonance imaging (MRI) of the frontal lobe in monozygotic (MZ) twins concordant or discordant for schizophrenia and healthy MZ control twins.
The sample comprised 21 concordant pairs, 17 discordant affected and 18 discordant unaffected twins from 19 discordant pairs, and 27 control pairs. Groups were matched on sociodemographic variables. Patient groups (concordant, discordant affected) did not differ on clinical variables. Volumes of superior, middle, inferior and orbital frontal gyri were calculated using the Cavalieri principle on the basis of manual tracing of anatomic boundaries. Group differences were investigated covarying for whole-brain volume, gender and age.
Results for superior frontal gyrus showed that twins with schizophrenia (i.e. concordant twins and discordant affected twins) had reduced volume compared to twins without schizophrenia (i.e. discordant unaffected and control twins), indicating an effect of illness. For middle and orbital frontal gyrus, concordant (but not discordant affected) twins differed from non-schizophrenic twins. There were no group differences in inferior frontal gyrus volume.
These findings suggest that volume reductions in the superior frontal gyrus are associated with a diagnosis of schizophrenia (in the presence or absence of a co-twin with schizophrenia). On the other hand, volume reductions in middle and orbital frontal gyri are seen only in concordant pairs, perhaps reflecting the increased genetic vulnerability in this group.
There is increasing evidence for a neurobiological basis of antisocial personality disorder (ASPD), includinggenetic liability, aberrant serotonergic function, neuropsychological deficits and structural and functional brain abnormalities. However, few functional brain imaging studies have been conducted using tasks of clinically relevant functions such as impulse control and reinforcement processing. Here we report on a study investigating the neural basis of behavioural inhibition and reward sensitivity in ASPD using functional magnetic resonance imaging (fMRI).
17 medication-free male individuals with DSM IV ASPD and 14 healthy controls were included. All subjects were screened for Axis I pathology and substance misuse. Scanner tasks included two block design tasks: one Go/No-Go task and one reward task. Scanning was carried out on a 1.5T Phillips system. Whole brain coverage was achieved using 40 axial slices with 3.5mm spacing a TR of 5 seconds. Data were analysed using SPM5 using random effects models.
Results of the Go/No-Go task confirmed brain activation previously described in the processing of impulse inhibition, namely in the orbitofrontal and dorsolateral prefrontal cortex and the anterior cingulate, and these were enhanced in the PD group. The reward task was associated with BOLD response changes in the reward network in both groups. However, these BOLD responses were reduced in the ASPD group, particularly in prefrontal areas.
Our results further support the notion of prefrontal dysfunction in ASPD. However, contrary to previous studies suggesting “hypofrontality” in this disorder, we found task specific increased and decreased BOLD responses.
Reconstructions of prehistoric vegetation composition help establish natural baselines, variability, and trajectories of forest dynamics before and during the emergence of intensive anthropogenic land use. Pollen–vegetation models (PVMs) enable such reconstructions from fossil pollen assemblages using process-based representations of taxon-specific pollen production and dispersal. However, several PVMs and variants now exist, and the sensitivity of vegetation inferences to PVM selection, variant, and calibration domain is poorly understood. Here, we compare the reconstructions, parameter estimates, and structure of a Bayesian hierarchical PVM, STEPPS, both to observations and to REVEALS, a widely used PVM, for the pre–Euro-American settlement-era vegetation in the northeastern United States (NEUS). We also compare NEUS-based STEPPS parameter estimates to those for the upper midwestern United States (UMW). Both PVMs predict the observed macroscale patterns of vegetation composition in the NEUS; however, reconstructions of minor taxa are less accurate and predictions for some taxa differ between PVMs. These differences can be attributed to intermodel differences in structure and parameter estimates. Estimates of pollen productivity from STEPPS broadly agree with estimates produced for use in REVEALS, while comparison between pollen dispersal parameter estimates shows no significant relationship. STEPPS parameter estimates are similar between the UMW and NEUS, suggesting that STEPPS parameter estimates are transferable between floristically similar regions and scales.
The available literature suggests that treatments and health services for psychosis are considered to be poorly organized and highly variable. Little is known, however, about how inpatient care is provided to individuals experiencing early psychosis. To facilitate quality improvement activities, we characterized the care this patient group receives in an inner city hospital.
We performed chart reviews of individuals admitted to psychiatric inpatient units at St. Paul's Hospital, Vancouver, British Columbia between 01/04/2014 and 31/03/2016. Those who were 17–25 years of age and hospitalized for psychotic symptoms at the time of admission were included. Demographic and health service use were summarized using descriptive characteristics.
We identified 73 inpatients (mean age = 22; males = 78%; Caucasian = 41%) that met study inclusion criteria, having a combined total of 102 care episodes and an average length of stay of 30.7 days (median = 18; min = 3; max = 268). Half of the care episodes were repeat admissions, with up to 30% of the patients readmitted within 28 days of discharge. Physical and mental status examinations (MSE) were performed in virtually all care episodes, although frequency is low (31.4% had daily physical examinations and 18.6% had MSE every nursing shift). In 49% and 50% of care episodes, patients were given oral antipsychotics and discharged on depot medications. Even when indicated, not all care episodes had follow-up appointments (60%) or referrals to income assistance (35%), community mental health teams (61%), and housing support (38%).
Specific programs are needed to address current gaps in inpatient care for patients with early psychosis.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Methadone, a long-acting opioid agonist commonly used in the treatment of opiate dependence, has been reported to cause QTc interval prolongation, increasing the risk of a fatal cardiac arrhythmia – Torsades-de-Pointes (TdP). This effect seems to be attributable to methadone's inhibitory effect on the cardiac “hERG”-K+ ion channel and is dose-dependent. There is a lack of consensus regarding when to perform an ECG for patients on methadone.
Identifying other TdPPRFs in a cohort of patients receiving ≥ 85 mg (high dose) methadone daily to inform local clinical safety guidelines.
Our outpatient caseload was filtered to select opiate-dependent patients receiving more than 85 mg methadone daily. Primary care summaries and laboratory results databases were analysed for the presence of other TdPPRFs: female sex a documented history of ECG abnormalities, electrolyte imbalance, liver or renal failure, and concomitant use of other QT prolonging medication or stimulants.
Fourteen opiate-dependent patients (10.29% of patients on methadone) were maintained on ≥ 85 mg methadone daily. Gender distribution was F:M = 1:1.8; 64% misused illicit stimulants; 57% were prescribed other QTc prolonging medication and 29% had a documented history of liver/renal failure or electrolyte imbalance. Only 14% had previous ECGs documented in primary care summaries. Of patients on high dose methadone, 85.7% had at least one TdPPRFs present and 64.3% had at least two.
These results demonstrate an increased rate of TdPPRFs in this patient group and highlight the importance of ECG monitoring which ideally should be offered to patients receiving even lower doses of methadone.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
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.
Little is known about emotional quality-of-life in paediatric heart disease in low- and middle-income countries where the prevalence of uncorrected lesions is high. Research on emotional quality-of-life and its predictors in these settings is key to planning interventions.
Ten-year retrospective cross-sectional study of children aged 6–17 years with uncorrected congenital or acquired heart disease in 12 low- and middle-income countries was conducted. Emotional functioning score of the PedsQL TM 4.0 generic core scale and data on patient-reported limitation in sports participation were collected via in-person interview and analysed using regression analyses.
Ninety-four children reported mean emotional functioning scores of 71.94 (SD 25.32) [95% CI 66.75–77.13] with lower scores independently associated with having a parent with a chronic illness or who had died (p = 0.005), having less than three siblings (p = 0.007), and reporting a subjective limitation in carrying an item equivalent to a 4 lb load (p = 0.021). Patient-reported limitation in sports participation at least “sometimes” was present in 69% and was independently associated with experiencing symptoms at least once a month (p < 0.001).
Some of the factors which were associated with better emotional quality-of-life were similar to those identified in previous studies in patients with corrected defects. Patient-reported limitation in sports participation is common. In addition to corrective surgery and exercise, numerous other interventions which are practicable during surgical missions might improve emotional quality-of-life.