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Research was conducted from 2013 to 2015 across three sites in Mississippi to evaluate corn response to sublethal paraquat or fomesafen (105 and 35 g ai ha−1, respectively) applied PRE, or to corn at the V1, V3, V5, V7, or V9 growth stages. Fomesafen injury to corn at three d after treatment (DAT) ranged from 0% to 38%, and declined over time. Compared with the nontreated control (NTC), corn height 14 DAT was reduced approximately 15% due to fomesafen exposure at V5 or V7. Exposure at V1 or V7 resulted in 1,220 and 1,110 kg ha−1 yield losses, respectively, compared with the NTC, but yield losses were not observed at any other growth stage. Fomesafen exposure at any growth stage did not affect corn ear length or number of kernel rows relative to the NTC. Paraquat injury to corn ranged from 26% to 65%, depending on growth stage and evaluation interval. Corn exposure to paraquat at V3 or V5 consistently caused greater injury across evaluation intervals, compared with other growth stages. POST timings of paraquat exposure resulted in corn height reductions of 13% to 50%, except at V7, which was most likely due to rapid internode elongation at that stage. Likewise, yield loss occurred after all exposure times of paraquat except PRE, compared with the NTC. Corn yield was reduced 1,740 to 5,120 kg ha−1 compared with the NTC, generally worsening as exposure time was delayed. Paraquat exposure did not reduce corn ear length, compared with the NTC, at any growth stage. However, paraquat exposure at V3 or V5 was associated with reduction of kernel rows by 1.1 and 1.7, respectively, relative to the NTC. Paraquat and fomesafen applications near corn should be avoided if conditions are conducive for off-target movement, because significant injury and yield loss can result.
In recent years, the use of cover crops has increased in U.S. crop production systems. An important aspect of successful cover crop establishment is the preceding crop and herbicide program, because some herbicides have the potential to persist in the soil for several months. Few studies have been conducted to evaluate the sensitivity of cover crops to common residual herbicides used in soybean production. The same field experiment was conducted in 2016 in Arkansas, Illinois, Indiana, Missouri, Tennessee, and Wisconsin, and repeated in Arkansas, Illinois, Indiana, Mississippi, and Missouri in 2017 to evaluate the potential of residual soybean herbicides to carryover and reduce cover crop establishment. Herbicides applied during the soybean growing season included acetochlor; acetochlor plus fomesafen; chlorimuron plus thifensulfuron; fomesafen; fomesafen plus S-metolachlor followed by acetochlor; imazethapyr; pyroxasulfone; S-metolachlor; S-metolachlor plus fomesafen; sulfentrazone plus S-metolachlor; sulfentrazone plus S-metolachlor followed by fomesafen plus S-metolachlor; and sulfentrazone plus S-metolachlor followed by fomesafen plus S-metolachlor followed by acetochlor. Across all herbicide treatments, the sensitivity of cover crops to herbicide residues in the fall, from greatest to least, was forage radish = turnip > annual ryegrass = winter oat = triticale > cereal rye = Austrian winter pea = hairy vetch = wheat > crimson clover. Fomesafen (applied 21 and 42 days after planting [(DAP]); chlorimuron plus thifensulfuron and pyroxasulfone applied 42 DAP; sulfentrazone plus S-metolachlor followed by fomesafen plus S-metolachlor; and sulfentrazone plus S-metolachlor followed by fomesafen plus S-metolachlor followed by acetochlor caused the highest visual ground cover reduction to cover crop species at the fall rating. Study results indicate cover crops are most at risk when following herbicide applications in soybean containing certain active ingredients such as fomesafen, but overall there is a fairly low risk of cover crop injury from residual soybean herbicides applied in the previous soybean crop.
Sex-specific diagnostic cut-offs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction (MI). The objective of this study was to quantify test characteristics of sex-specific cut-offs of a single, high-sensitivity cardiac troponin T (hs-cTnT) assay for 7-day MI in patients with chest pain.
This observational cohort study included consecutive emergency department (ED) patients with suspected cardiac chest pain from four Canadian EDs who had an hs-cTnT assay performed within 60 minutes of ED arrival. The primary outcome was MI at 7 days. We quantified test characteristics (sensitivity, negative predictive value [NPV], likelihood ratios and proportion of patients ruled out) for multiple combinations of sex-specific, rule-out cut-offs. We calculated the net reclassification index compared to universal rule-out cut-offs.
In 7,130 patients (3,931 men and 3,199 women), the 7-day MI incidence was 7.38% among men and 3.78% among women. Optimal sex-specific cut-offs (<8 ng/L for men and <7 ng/L for women) had a 98.5% sensitivity for MI and ruled out MI in 55.8% of patients. This would enable an absolute increase in the proportion of patients who were able to be ruled out with a single hs-cTnT of 13.2% to 22.2%, depending on the universal rule-out concentration used as a comparator.
Sex-specific hs-cTnT cut-offs for ruling out MI at ED arrival may improve classification performance, enabling more patients to be safely ruled out at ED arrival. However, differences between sex-specific and universal cut-off concentrations are within the variation of the assay, limiting the clinical utility of this approach. These findings should be confirmed in other data sets.
Structured clinical judgement tools provide scope for the standardisation of forensic service gatekeeping and also allow identification of heuristics in this decision process. The DUNDRUM-1 triage tool was completed retrospectively for 121 first-time referrals to forensic services in South Wales. Fifty were admitted to medium security, 49 to low security and 22 remained in open conditions.
DUNDRUM-1 total scores differed appropriately between different levels of security. However, regression revealed heuristic anchoring on the ‘legal process’ and ‘immediacy of risk due to mental disorder’ items.
Patient placement was broadly aligned with DUNDRUM-1 recommendations. However, not all triage items informed gatekeeping decisions. It remains to be seen whether decisions anchored in this way are effective.
Declaration of interest
Dr Mark Freestone gave permission for AUC values from Freestone et al. (2015) to be presented here for comparison.
Soybean consultants from Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee were surveyed in 2016 to assess weed management practices and the prevalence of herbicide-resistant weeds in midsouthern U.S. soybean production. The consultants surveyed represented 13%, 28%, 8%, 16%, and 5% of the total soybean area planted in Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee, respectively. Of the total scouted area, 78% of the consultants said their growers planted glyphosate-resistant soybean in 2016, with 18% planting glufosinate-resistant (LibertyLink®), primarily due to familiarity with and cost of the technology. Although 94% of the consultants determined that glufosinate was most effective on killing Palmer amaranth, the primary concern associated with controlling herbicide-resistant weeds was the associated cost, followed by return profit and time constraints. Palmer amaranth, morningglory species, horseweed, barnyardgrass, and Italian ryegrass were the five most problematic weeds in soybean across the five states. Palmer amaranth was the most problematic and important weed in each state individually. The increased concern (77% of consultants) with this species was attributed to the rising concern with and occurrence of protoporphyrinogen oxidase–resistant Palmer amaranth. Consultants were of the opinion that more research was needed on cover crops and the new traited technologies in order to improve weed management in soybean.
To investigate the burden of medical comorbidity in a population receiving in-patient treatment for drug and alcohol problems. All patients admitted over a 6-month period were included in the data-set. We recorded diagnostic information on admission that allowed the calculation of predicted 10-year survival using a previously validated comorbidity index.
Despite the majority of the sample having a predicted 10-year survival chance of greater than 75%, a sizeable minority (16.7%) are carrying a high burden of medical comorbidity, with a predicted 10-year survival chance of less than 50%. More than half (55.2%) of these patients were under the age of 55. Chronic respiratory disease was the most frequent diagnosis.
In-patient substance misuse units serve a complicated group of patients, whose needs are met by active medical input, resident medical cover and effective liaison with general hospitals. This is important when planning and commissioning treatment services. The high burden of respiratory disease suggests the utility of robust smoking cessation interventions among this population.
This paper employs survey experiments to examine how contextualizing the claims made in negative political advertising affects perceptions of their fairness. This has implications for the components of fairness judgments, e.g., if “truth” is a component of fairness, being informed that a claim is untrue should undermine perceptions of its fairness, as well as for the efficacy of “fact-checking.” Our experiments on a random national telephone sample show some effects of being informed that a claim is untrue but few if it is characterized as taken out of context or as irrelevant. These findings imply that: (a) while evaluations of the truth of claims appear to be a component of fairness, considerations such as whether claims are the “whole story” or “relevant” to the decision at hand do not, and (b) contextualizing of the claims of ads in fact-checks has very little impact on perceptions of their fairness.
Millisecond pulsars (MSPs) are a class of radio pulsars with extremely stable rotation. Their excellent timing stability can be used to study a wide variety of astrophysical phenomena. In particular, a large sample of these pulsars can be used to detect low-frequency gravitational waves. We have developed a precision pulsar timing backend for the NASA Deep Space Network (DSN), which will allow the use of short gaps in tracking schedules to time pulses from an ensemble of MSPs. The DSN operates clusters of large dish antennas (up to 70-m in diameter), located roughly equidistant around the Earth, for communication and tracking of deep-space spacecraft. The backend system will be capable of removing entirely the dispersive effects of propagation of radio waves through the interstellar medium in real-time. We will describe our development work, initial results, and prospects for future observations over the next few years.
A survey questionnaire was sent to cotton consultants of Arkansas and Mississippi through direct mail and Louisiana and Tennessee consultants through on-farm visits in fall of 2011. The survey was returned by a total of 22 Arkansas, 17 Louisiana, 10 Mississippi, and 11 Tennessee cotton consultants, representing 26, 53, 13, and 38% of total cotton planted in these states in 2011, respectively. Collectively, the area planted to glyphosate-resistant (Roundup Ready®, RR) cotton was 97%, glyphosate plus glufosinate-resistant (Widestrike® Flex, WRF) cotton was 30%, and glufosinate-resistant (Liberty Link, LL) cotton was 2.6% of the total cotton surveyed in 2011. Seventy percent of area in all states is still under continuous RR/WRF cotton. Average cost of herbicides in RR systems was $114 ha−1 and in LL systems was $137 ha−1. Across the states, cotton planted under no-tillage, conservation tillage, and conventional tillage was 31, 36, and 33%, respectively, of total scouted cotton. Area under conventional tillage increased and conservation tillage decreased in Arkansas compared with a previous survey conducted in 2006. Palmer amaranth, morningglories, and horseweed in the order of listing were the most problematic weeds of cotton across Arkansas, Mississippi, and Tennessee. In Louisiana, however, morningglories were the most problematic weed followed by Palmer amaranth and common waterhemp. Glyphosate-resistant (GR) Palmer amaranth infested only 13% of scouted cotton area in Louisiana compared with 75% in the remaining three states, and consequently, hand-weeding to control GR Palmer amaranth is practiced on only 2.5% of total scouted area of Louisiana and 49% of the scouted area of the remaining three states. Hand-weeding added an additional $12 to 371 ha−1 to weed-management costs. One-half (50%) of the cotton consultants emphasized the need for more research on residual herbicides that can control GR Palmer amaranth effectively.
In fall 2011, cotton and soybean consultants from Arkansas, Louisiana, Mississippi, and Tennessee were surveyed through direct mail and on-farm visits, and rice consultants from Arkansas and Mississippi were surveyed through direct mail to assess the importance and level of implementation of herbicide resistance best management practices (HR-BMPs) for herbicide-resistant weeds. Proper herbicide timing, clean start with no weeds at planting, application of multiple effective herbicide modes of action, use of full labeled herbicide rates, and prevention of crop weed seed production with importance rating of ≥ 4.6 out of 5.0 were perceived as the most important HR-BMPs in all crops. Purchase of certified rice seed was on 90% of scouted hectares. In contrast, least important HR-BMPs as perceived by consultants with importance ratings of ≤ 4.0 in cotton, ≤ 3.7 in rice, and ≤ 3.8 in soybean were cultural practices such as manual removal of weeds; tillage including disking, cultivation, or deep tillage; narrow (≤ 50 cm)-row crops, cover crops, and altered planting dates. Narrow crop rows and cover crops in cotton; altered planting dates in cotton and soybean; and cleaning of farm equipment and manual weeding in rice and soybean is currently employed on ≤ 20% of scouted hectares. Extra costs, time constraints, adverse weather conditions, lack of labor and equipment, profitability, herbicide-related concerns, and complacency were perceived as key obstacles for adoption of most HR-BMPs. With limited adoption of most cultural practices that reduce risks of herbicide-resistant weeds, there are opportunities to educate growers concerning the proactive need and long-term benefits of adopting HR-BMPs to ensure sustainable weed management and profitable crop production.