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North Carolina growers have long struggled to control Italian ryegrass, and recent research has confirmed Italian ryegrass biotypes resistant to nicosulfuron, glyphosate, clethodim, and paraquat. Integrating alternative management strategies is crucial to effectively control such biotypes. The objectives of this study were to evaluate Italian ryegrass control with cover crops and fall-applied residual herbicides and investigate cover crop injury from residual herbicides. This study was conducted during the fall/winter of 2021-22 in Salisbury and fall/winter of 2021-22 and 2022-23 at Clayton, NC. The study was designed as a 3x5 split-plot, where the main plot consisted of three cover crop treatments (no-cover, cereal rye at 80 kg ha-1, and crimson clover at 18 kg ha-1), and the subplots consisted of five residual herbicide treatments (S-metolachlor, flumioxazin, metribuzin, pyroxasulfone, and nontreated). In the 2021-22 season at Clayton, metribuzin injured cereal rye and crimson clover 65% and 55%, respectively. However, metribuzin injured both cover crops ≤6% in 2022-23. Flumioxazin resulted in unacceptable crimson clover injury with 50% and 38% in 2021-22 and 2022-23 in Clayton and 40% at Salisbury, respectively. Without preemergence herbicides, cereal rye controlled Italian ryegrass 85% and 61% at 24 WAP in 2021-22 and 2022-23 at Clayton and 82% in Salisbury, respectively. In 2021-22, Italian ryegrass seed production was lowest in cereal rye treatments at both locations, except when cover crop was treated with metribuzin. For example, in Salisbury, cereal rye plus metribuzin resulted in 39324 seeds m–2, compared to ≤4386 seeds m–2 from all other cereal rye treatments. In 2022-23, Italian ryegrass seed production in cereal rye was lower when either metribuzin or pyroxasulfone were used PRE (2670 and 1299 seeds m–2, respectively) when compared to cereal rye without herbicides (5600 seeds m–2).
Two studies were conducted in 2022 and 2023 near Rocky Mount and Clayton, NC, to determine the optimal granular ammonium sulfate (AMS) rate and application timing for pyroxasulfone-coated AMS. In the rate study, AMS rates included 161, 214, 267, 321, 374, 428, and 481 kg ha-1, equivalent to 34, 45, 56, 67, 79, 90, and 101 kg N ha-1, respectively. All rates were coated with pyroxasulfone at 118 g ai ha-1 and top-dressed onto 5- to 7-leaf cotton. In the timing study, pyroxasulfone (118 g ai ha-1) was coated on AMS and top-dressed at 321 kg ha-1 (67 kg N ha-1) onto 5- to 7-leaf, 9- to 11-leaf, and first bloom cotton. In both studies, weed control and cotton tolerance to pyroxasulfone-coated AMS was compared to pyroxasulfone applied postemergence (POST) and postemergence-directed (POST-directed). The check in both studies received non-herbicide-treated AMS (321 kg ha-1). Before treatment applications, all plots (including the check) were maintained weed-free with glyphosate and glufosinate. In both studies, pyroxasulfone applied POST was most injurious (8 to 16%), while pyroxasulfone-coated AMS resulted in ≤ 4% injury. Additionally, no differences in cotton lint yield were observed in both studies. With the exception of the lowest rate of AMS (161 kg ha-1; 79%), all AMS rates coated with pyroxasulfone controlled Palmer amaranth ≥ 83%, comparable to pyroxasulfone applied POST (92%) and POST-directed (89%). In the timing study, the application method did not affect Palmer amaranth control; however, applications made at the mid- and late timings outperformed early applications. These results indicate pyroxasulfone-coated AMS can control Palmer amaranth comparable to pyroxasulfone applied POST and POST-directed, with minimal risk of cotton injury. However, the application timing could warrant additional treatment to achieve adequate late-season weed control.
A factorial study of fluency was undertaken to test an hypothesis that at least two fluency abilities would be measured by a battery composed both of word fluency tests used by Thurstone and tests of fluency described by several British investigators. Twenty-eight tests, including ten reference tests for five primary mental abilities, were administered to 181 high-school seniors. Ten centroid factors were extracted, a simple structure was found, and eight factors were interpreted. Five factors defined were the following reference abilities: memory (M), number (N), reasoning (R), verbal comprehension (V), and perceptual speed (P), the last one being somewhat tentatively identified. The main finding is the analysis of fluency into two factors: word fluency (W) and ideational fluency (F). Word fluency is defined as a facility in producing single, isolated words that contain one or more formal restrictions, without reference to the meaning of the words. Ideational fluency is described as a facility in expressing ideas by the use of words and their meanings. Another verbal ability indicated is tentatively interpreted as verbal versatility, the ability to express essentially the same idea by means of several different words or combinations of words.
The relationship between measures of verbal fluency and certain personality traits is examined by factor techniques. From a matrix of eight factor scores derived from mental tests plus five personality scores, six factors were obtained. An oblique solution lends limited support to the hypothesized relationship between the two domains.
For any fixed total time of testing it is possible, through proper item-and-time allotment, to combine tests into a battery so that the multiple correlation with a pre-assigned criterion will be maximized. By holding constant the ratio of the length in number of items to the time length for each test, a set of general equations has been derived which will yield this maximum value of the multiple R and will enable one to determine, in any given case, the optimal fraction of total testing time that should be devoted to each type of test under consideration. The set of general equations is applied to a two-test-battery problem to obtain the optimal length of each type of test for one hour total testing time. If two other tests had been selected for the two-test sample problem, different subdivisions of the total time would generally occur. The manner in which the results would change when using other tests with different initial reliability, validity, and intercorrelation values is briefly presented. Some general implications of this method of battery development are also discussed.
England's primary care service for psychological therapy (Improving Access to Psychological Therapies [IAPT]) treats anxiety and depression, with a target recovery rate of 50%. Identifying the characteristics of patients who achieve recovery may assist in optimizing future treatment. This naturalistic cohort study investigated pre-therapy characteristics as predictors of recovery and improvement after IAPT therapy.
Methods
In a cohort of patients attending an IAPT service in South London, we recruited 263 participants and conducted a baseline interview to gather extensive pre-therapy characteristics. Bayesian prediction models and variable selection were used to identify baseline variables prognostic of good clinical outcomes. Recovery (primary outcome) was defined using (IAPT) service-defined score thresholds for both depression (Patient Health Questionnaire [PHQ-9]) and anxiety (Generalized Anxiety Disorder [GAD-7]). Depression and anxiety outcomes were also evaluated as standalone (PHQ-9/GAD-7) scores after therapy. Prediction model performance metrics were estimated using cross-validation.
Results
Predictor variables explained 26% (recovery), 37% (depression), and 31% (anxiety) of the variance in outcomes, respectively. Variables prognostic of recovery were lower pre-treatment depression severity and not meeting criteria for obsessive compulsive disorder. Post-therapy depression and anxiety severity scores were predicted by lower symptom severity and higher ratings of health-related quality of life (EuroQol questionnaire [EQ5D]) at baseline.
Conclusion
Almost a third of the variance in clinical outcomes was explained by pre-treatment symptom severity scores. These constructs benefit from being rapidly accessible in healthcare services. If replicated in external samples, the early identification of patients who are less likely to recover may facilitate earlier triage to alternative interventions.
To evaluate the impact of receptive vocabulary versus years of education on neuropsychological performance of Black and White older adults.
Method:
A community-based prospectively enrolled cohort (n = 1,007; 130 Black, 877 White) in the Emory Healthy Brain Study were administered the NIH Toolbox Picture Vocabulary Test and neuropsychological measures. Group differences were evaluated with age, sex, and education or age, sex, and Toolbox Vocabulary scores as covariates to determine whether performance differences between Black versus White participants were attenuated or eliminated.
Results:
With vocabulary as a covariate, the main effect of race was no longer significant for the MoCA, Phonemic Fluency, Rey Auditory Verbal Learning Test, and Rey Complex Figure Test immediate and delayed recall. Although still significantly different between groups, the effect sizes for Animal Fluency, Trails B-A, Symbol Digit Modalities Test, and Rey Copy were attenuated, with the greatest reductions occurring for the Multilingual Naming Test and Judgment of Line Orientation.
Conclusions:
Findings support the value of using receptive vocabulary as a proxy for premorbid ability level when comparing the cognitive performance of Black and White older adults. The results extend investigations using measures of single word reading to encompass measures assessing word meaning.
The introduction of portable MRI (pMRI) has the potential to directly impact dementia research and ultimately clinical care. In this paper, we explore two ethical challenges facing the introduction of pMRI in dementia research. The first is the need to ensure that pMRI enhances rather than undermines efforts aimed at improving ethnoracial representation in dementia research. The second is the need to implement pMRI in dementia research in a dementia-friendly way that attends to the social context and lived experience of people with dementia.
An experiment was conducted in 2022 and 2023 near Rocky Mount and Clayton, NC, to evaluate residual herbicide-coated fertilizer for cotton tolerance and Palmer amaranth control. Treatments included acetochlor; atrazine; dimethenamid-P; diuron; flumioxazin; fluometuron; fluridone; fomesafen; linuron; metribuzin; pendimethalin; pyroxasulfone; pyroxasulfone + carfentrazone; S-metolachlor; and sulfentrazone. Each herbicide was individually coated on granular ammonium sulfate (AMS) and top-dressed at 321 kg ha-1 (67 kg N ha-1) onto 5- to 7-leaf cotton. The check received the equivalent rate of non-herbicide-treated AMS. Before top-dress, all plots (including the check) were treated with glyphosate and glufosinate to control previously emerged weeds. All herbicides resulted in transient cotton injury, except metribuzin. Cotton response to metribuzin varied by year and location. In 2022, metribuzin caused 11 to 39% and 8 to 17% injury at Clayton and Rocky Mount, respectively. In 2023, metribuzin caused 13 to 32% injury at Clayton and 73 to 84% injury at Rocky Mount. Pyroxasulfone (91%), pyroxasulfone + carfentrazone (89%), fomesafen (87%), fluridone (86%), flumioxazin (86%), and atrazine (85%) controlled Palmer amaranth ≥ 85%. Pendimethalin and fluometuron were the least effective treatments, resulting in 58% and 62% control, respectively. As anticipated, early season metribuzin injury translated into yield loss; plots treated with metribuzin yielded 640 kg ha-1 and were only comparable to linuron (790 kg ha-1). These findings research suggest, with the exception of metribuzin, residual herbicides coated on AMS may be suitable and effective in cotton production, providing growers with additional modes of action for late-season control of multiple herbicide-resistant Palmer amaranth.
We use large-eddy simulations to study the penetration of a buoyant plume carrying a passive tracer into a stably stratified layer with constant buoyancy frequency. Using a buoyancy-tracer volume distribution, we develop a method for objectively partitioning plume fluid in buoyancy-tracer space into three regions, each of which corresponds to a coherent region in physical space. Specifically, we identify a source region where undiluted plume fluid enters the stratified layer, a transport region where much of the transition from undiluted to mixed fluid occurs in the plume cap and an accumulation region corresponding to a radially spreading intrusion. This method enables quantification of different measures of turbulence and mixing within each of the three regions, including potential energy and turbulent kinetic energy dissipation rates, an activity parameter and the instantaneous mixing efficiency. We find that the most intense buoyancy gradients lie in a thin layer at the cap of the penetrating plume. This provides the primary stage of mixing between plume and environment and exhibits a mixing efficiency around 50 %. Newly generated mixtures of environmental and plume fluid join the intrusion and experience relatively weak turbulence and buoyancy gradients. As the intrusion spreads radially, environmental fluid surrounding the intrusion is mixed into the intrusion with moderate mixing efficiency. This dominates the volume of environmental fluid entrained into the region containing plume fluid. However, the ‘strongest’ entrainment, as measured by the specific entrainment rate, is largest in the plume cap, where the most buoyant environmental fluid is entrained.
In December 2018, an outbreak of Salmonella Enteritidis infections was identified in Canada by whole-genome sequencing (WGS). An investigation was initiated to identify the source of the illnesses, which proved challenging and complex. Microbiological hypothesis generation methods included comparisons of Salmonella isolate sequence data to historical domestic outbreaks and international repositories. Epidemiological hypothesis generation methods included routine case interviews, open-ended centralized re-interviewing, thematic analysis of open-ended interview data, collection of purchase records, a grocery store site visit, analytic comparison to healthy control groups, and case–case analyses. Food safety hypothesis testing methods included food sample collection and analysis, and traceback investigations. Overall, 83 cases were identified across seven provinces, with onset dates from 6 November 2018 to 7 May 2019. Case ages ranged from 1 to 88 years; 60% (50/83) were female; 39% (22/56) were hospitalized; and three deaths were reported. Brand X profiteroles and eclairs imported from Thailand were identified as the source of the outbreak, and eggs from an unregistered facility were hypothesized as the likely cause of contamination. This study aims to describe the outbreak investigation and highlight the multiple hypothesis generation methods that were employed to identify the source.
An investigation into an outbreak of Salmonella Newport infections in Canada was initiated in July 2020. Cases were identified across several provinces through whole-genome sequencing (WGS). Exposure data were gathered through case interviews. Traceback investigations were conducted using receipts, invoices, import documentation, and menus. A total of 515 cases were identified in seven provinces, related by 0–6 whole-genome multi-locus sequence typing (wgMLST) allele differences. The median age of cases was 40 (range 1–100), 54% were female, 19% were hospitalized, and three deaths were reported. Forty-eight location-specific case sub-clusters were identified in restaurants, grocery stores, and congregate living facilities. Of the 414 cases with exposure information available, 71% (295) had reported eating onions the week prior to becoming ill, and 80% of those cases who reported eating onions, reported red onion specifically. The traceback investigation identified red onions from Grower A in California, USA, as the likely source of the outbreak, and the first of many food recall warnings was issued on 30 July 2020. Salmonella was not detected in any tested food or environmental samples. This paper summarizes the collaborative efforts undertaken to investigate and control the largest Salmonella outbreak in Canada in over 20 years.
Aluminum-substituted hematites (Fe2−xAlxO3) were synthesized from Fe-Al coprecipitates at pH 5.5, 7.0, and in 10−1, 10−2, and 10−2 M KOH at 70°C. As little as 1 mole % Al suppressed goethite completely at pH 7 whereas in KOH higher Al concentrations were necessary. Al substitution as determined chemically and by XRD line shift was related to Al addition up to a maximum of 16–17 mole %. The relationship between the crystallographic a0 parameter and Al substitution deviated from the Vegard rule. At low substitution crystallinity of the hematites was improved whereas higher substitution impeded crystal growth in the crystallographic z-direction as indicated by differential XRD line broadening. At still higher Al addition crystal growth was strongly retarded. The initial Al-Fe coprecipitate behaved differently from a mechanical mixture of the respective “hydroxides” and was, therefore, considered an aluminous ferrihydrite.
The small angle X-ray scattering data obtained in an earlier investigation of a series of Na-montmorillonite clay samples containing varying concentrations of sodium metaphosphate have been used to calculate the potential energy φ(x) of the interaction between two isolated parallel clay platelets separated by a distance x. All φ(x) curves have the form expected for Na-montmorillonite. In each curve there is a potential well for a platelet separation approximately equal to the most probable separation distance determined in the earlier study. Because the depth of the potential well is of the order of 0·01 eV for all samples, the attractive forces are relatively weak. While the calculated φ(x) functions are not highly accurate, in future investigations precautions can be taken to increase the reliability of the computed potential energy functions. This preliminary study suggests that determination of φ(x) from small angle X-ray scattering data can be a useful method for quantitative study of interparticle forces in Na-montmorillonite clays.
The most prominent authigenic reaction in Holocene tuffaceous sediments at Teels Marsh, Nevada, is the hydration of rhyolitic glass by interstitial brines and the subsequent formation of phillipsite. This reaction has the form: rhyolitic glass + H2O → hydrous alkali alumninosilicate gel → phillipsite. Phillipsite is the most abundant authigenic phase in the tuffaceous sediments (>95%), analcime is the next most abundant phase, and clinoptilolite occurs as a trace mineral in the <2-mm fraction. Analcime forms by the reaction of phillipsite and Na+. Gaylussite and searlesite also are common authigenic phases at Teels Marsh. The concentration of silica in the interstitial brines is controlled by one or more of the authigenic reactions at less than 100 ppm. A stoichiometric equation for the reaction of phillipsite to analcime at Teels Marsh is:
Sodium and potassium activities of brines associated with both phillipsite and analcime were used to estimate the equilibrium constant for this reaction as 3.04 × 10−5. The ΔG0 value for the reaction is +6.2 kcal/mole at 25°C and 1 atm pressure. The estimated ΔG0 value of phillipsite, using this reaction, is −1072.8 kcal/mole at 25°C and 1 atm.
Removal and disposal of nonnative trees is expensive and time-consuming. Using these nonnative trees as a substrate to produce edible mushrooms could diversify farming operations and provide additional income to small-scale farmers. This research compared the production of shiitake mushrooms (Lentinula edodes) on nonnative tree logs to shiitake mushroom production on native oak (Quercus L.) logs, which are the traditional substrate. In a 2-yr study, we evaluated nonnative tree species as alternate substrates for growing shiitake mushrooms at farms in northern Florida and southern Georgia. A mix of native Quercus spp. and nonnative trees was targeted for removal on participating farms. Five nonnative tree species were initially tested for their ability to produce edible mushrooms, either shiitake or oyster (Pleurotus ostreatus var. florida). Of the nonnative trees we tested: Chinaberry (Melia azedarach L.), Chinese tallowtree [Triadica sebifera (L.) Small], silktree (Albizia julibrissin Durazz.), earleaf acacia (Acacia auriculiformis A. Cunn. ex Benth.), and paperbark tree [Melaleuca quinquenervia (Cav.) S.F. Blake], only T. sebifera produced shiitake mushrooms, and none produced native Florida oyster mushrooms. In on-farm trials, Quercus spp. logs produced more total mushrooms and more mushrooms per log and had a higher total mushroom yield per log. However, mushrooms produced on T. sebifera logs had higher mean weight per mushroom. Edible fungi can be used to recycle invasive, nonnative T. sebifera and transform their biomass from waste into an income-producing resource.
Towards developing more effective interventions for fall-related injuries, this study analysed a novel database from six retirement home facilities over a 4-year period comprising 1,877 fallers and 12,445 falls. Falls were characterized based on location, activity, injury site, and type, and the database was stratified across four levels of care: Independent Living, Retirement Care, Assisted Care, and Memory care. Falls most occurred within the bedroom (62.8%), and during unknown (38.1%), walking (20.2%), and transfer tasks (14.6%). Approximately one in three (37%) of all falls resulted in an injury, most commonly involving the upper limb (31.8%), head (26.3%), and lower limb (22.2%), resulting in skin tears (35.3%), aches/pains (29.1%), or bruises (28.0%). While fall location, activity, and injury site were different across levels of care, injury type was not. The data from this study can assist in targeting fall-related injury prevention strategies across levels of care within retirement facilities.