3,964 research outputs found

    PARAQUAT-RESISTANT ITALIAN RYEGRASS (Lolium multiflorum) CONFIRMED IN LOUISIANA

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    Paraquat is the only herbicide labeled for postemergence control of Italian ryegrass in sugarcane. In 2017, sugarcane farmers in Louisiana reported Italian ryegrass control failures with paraquat applications. Seeds were collected from sugarcane fields in White Castle, St. Gabriel, and Bunkie, Louisiana where control was not achieved (reduced susceptibility). Additionally, Italian ryegrass seeds were collected from a sugarcane field in Welcome, LA with a history of paraquat use and with no reported control issues (susceptible population). A dose-response study was conducted at the Louisiana State University Agricultural Center’s Sugar Research Station in February 2021 and was repeated in November 2021. Paraquat was applied to 8- to 12- cm tall Italian ryegrass plants at 0, 1/32 1/16, 1/8, 1/4, 1/2, 1, 2, 4, 8, and 16X rates, of the maximum field use rate of 840 g ha-1, for the reduced susceptibility populations. For the susceptible population, paraquat was applied at 0, 1/256, 1/128, 1/64, 1/32, 1/16, 1/8, 1/4, 1/2, 1, and 2X rates. At 18 d after application, injury was recorded, then biomass was harvested and dried for 96 h. Dose-response curves were fitted using a four-parameter, log-logistic model in R software. The effective paraquat dose to cause 50% injury (ED50) was 77 g ha-1 for the Welcome population, whereas it required 200.4, 22.2, and 45.4 -fold more paraquat for the White Castle, St. Gabriel, and Bunkie populations, respectively. Likewise, the ED50 value required to reduce the dry weight by 50% was 44 g ha-1 for the Welcome population. To reduce dry weight biomass for 50% for the White Castle, St. Gabriel, and Bunkie populations, required rates of 13.3, 4.3, and 14.3 -fold more paraquat, respectively, when compared to the Welcome population. These results confirm the presence of paraquat-resistant Italian ryegrass in Louisiana

    Diphenylphosphinobenzoic Acids as Linkers in [2,4,6– {(C10H21O)3C6H2NH}3C3N3] Triazine Adducts with Metal Complex, which Self–Organize into Room Temperature Hexagonal Columnar Mesophases

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    Producción CientíficaDisplacement of a labile ligand from appropriate precursor complexes by 2- or 4-PPh2C6H4COOH yields neutral gold(I) and gold(III) [AuXn(PPh2C6H4COOH)] (n = 1, X = Cl; n = 3, X = C6F5), cationic gold(I) [Au(PPh2C6H4COOH)2](CF3SO3), and neutral chromium(0) [Cr(CO)5(PPh2C6H4COOH)] metallo-organic acids. [AuCl(4-PPh2C6H4COOH)], [Au(C6F5)3(4-PPh2C6H4COOH)], and [Cr(CO)5(2-PPh2C6H4COOH)] have dimeric structures with typical carboxylic H-bond bridges, whereas [Au(C6F5)3(2-PPh2C6H4COOH)] gives a monomeric species with the carboxylic acid H bonded to cocrystallized solvent molecules. All gold-containing acids are emissive at 77 K in the range 404-520 nm and some of them also at 298 K with emission maxima from 441 to 485 nm. Reaction of these acid metal complexes with the triazine mesogen 2,4,6-{(C10H21O)3C6H2NH}3C3N3 affords some new hydrogen-bonded gold(I) and chromium(0) supramolecular adducts, but the related gold(III) complexes do not form adducts. The 4-diphenylphosphinobenzoic adducts display a columnar hexagonal mesophase (Colhex) at room temperature, with a random one-dimensional stacking of the pseudo-discoid triazine-metallo-organic adducts into columns, where the metallo-phosphinoacid fragments act as the fourth branch of the trifold triazine core. The 2-diphenylphosphinobenzoic mixtures do not display mesophases, as they appear in the X-ray studies as mixtures of the triazine and the metallo-phosphinoacid complex. The aggregates are luminescent at 77 K, with emission maxima in the range 419-455 nm.Ministerio de Economía, Industria y Competitividad (CTQ2011–25137)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA302U13

    Effects of COVID-19 lockdown on eating disorders and obesity: A systematic review and meta-analysis

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    OBJECTIVE: This systematic review and meta-analysis aimed to examine: the pooled prevalence of symptomatic behaviours and mental health deterioration amongst individuals with eating disorders (EDs) and obesity during the COVID-19 confinement. Moreover, we examined changes in EDs and distress before and during the confinement, and the association between psychosocial factors and EDs symptoms. METHOD: A systematic search was carried out in biomedical databases from January 2020 to January 2021. Both cross-sectional and longitudinal studies that used quantitative measures of ED symptoms and psychological distress during and after the COVID-19 confinement were included. RESULTS: A total of 26 studies met inclusion criteria (n = 3399, 85.7% female). The pooled prevalence of symptomatic deterioration in EDs was 65% (95% CI[48,81], k = 10). The pooled prevalence of increased weight in obesity was 52% (95% CI[25,78], k = 4). More than half of the participants experienced depression and anxiety. Moreover, at least 75% of the individuals with EDs reported shape and eating concerns, and increased thinking about exercising. However, the pooled analyses of longitudinal studies showed no significant differences from pre-pandemic levels to the first lockdown phase in Body Mass Index and ED symptoms, whereas only few studies suggested increased distress, particularly among individuals with anorexia nervosa. CONCLUSIONS: The majority of individuals with EDs and obesity reported symptomatic worsening during the lockdown. However, further longitudinal studies are needed to identify vulnerable groups, as well as the long-term consequences of COVID-19

    Effects of COVID-19 lockdown on eating disorders and obesity: A systematic review and meta-analysis

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    Objective: This systematic review and meta-analysis aimed to examine: the pooled prevalence of symptomatic behaviours and mental health deterioration amongst individuals with eating disorders (EDs) and obesity during the COVID-19 confinement. Moreover, we examined changes in EDs and distress before and during the confinement, and the association between psychosocial factors and EDs symptoms. Method: A systematic search was carried out in biomedical databases from January 2020 to January 2021. Both cross-sectional and longitudinal studies that used quantitative measures of ED symptoms and psychological distress during and after the COVID-19 confinement were included. Results: A total of 26 studies met inclusion criteria (n = 3399, 85.7% female). The pooled prevalence of symptomatic deterioration in EDs was 65% (95% CI[48,81], k = 10). The pooled prevalence of increased weight in obesity was 52% (95% CI[25,78], k = 4). More than half of the participants experienced depression and anxiety. Moreover, at least 75% of the individuals with EDs reported shape and eating concerns, and increased thinking about exercising. However, the pooled analyses of longitudinal studies showed no significant differences from pre-pandemic levels to the first lockdown phase in Body Mass Index and ED symptoms, whereas only few studies suggested increased distress, particularly among individuals with anorexia nervosa. Conclusions: The majority of individuals with EDs and obesity reported symptomatic worsening during the lockdown. However, further longitudinal studies are needed to identify vulnerable groups, as well as the long-term consequences of COVID-19

    Di-μ2-chlorido-dichloridoocta­methyldi-μ3-oxido-tetra­tin(IV) bis[chloridodimeth­yl(pyrrolidine-1-carbodithio­ato-κ2 S,S′)tin(IV)]

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    In the title co-crystal, [Sn4(CH3)8Cl4O2]·2[Sn(CH3)2Cl(C4H8NS2)], all the SnIV atoms are in distorted trigonal–bipyramidal environments. In the mononuclear species, the carbodithio­ate ligand is unsymmetrically coordinated to the SnIV atom, with Sn—S distances of 2.6722 (12) and 2.4706 (11) Å. All atoms with the exception of the methyl groups and one of the pyrrolidine ring CH2 groups lie on a crystallographic mirror plane. The pyrrolidine ring exhibits an envelope conformation; the C atom at the flap is disordered above and below the plane of symmetry with fixed occupation factors of 0.50. The centrosymmetric dimer species consists of a central Sn2O2 unit with two adjacent Sn2OCl four-membered rings

    Investigating hydrological contributions to volcano monitoring signals. A time-lapse gravity example

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    Geophysical techniques are widely used to monitor volcanic unrest. A number of studies have also demonstrated that hydrological processes can produce or trigger geophysical signals. Hydrologically-induced gravity signals have previously been recorded by specifically designed gravity surveys as well as, inadvertently, by volcano monitoring studies. Water table corrections of microgravity surveys are commonplace. However, the fluctuations of the water table beneath survey locations are often poorly known, and such a correction fails to account of changes in water-mass storage in the unsaturated zone. Here, we combine 2D axis-symmetrical numerical fluid-flow models with an axis-symmetric, distributed-mass, gravity calculation to model gravity changes in response to fluctuating hydrological recharge. Flow simulations are based on tropical volcanic settings where high surface permeabilities promote thick unsaturated zones. Our study highlights that mass storage (saturation) changes within the unsaturated zone beneath a survey point can generate recordable gravity changes. We show that for a tropical climate, recharge variations can generate gravity variations of over 150 μGal; although, we demonstrate that for the scenarios investigated here, the probability of recording such large signals, is low. Our modelling results indicate that microgravity survey corrections based on water table elevation may result in errors of up to 100 μGal. The effect of inter-annual recharge fluctuations dominate over seasonal cycles which makes prediction and correction of the hydrological contribution more difficult. Spatial hydrogeological heterogeneity can also impact on the accuracy of relative gravity surveys, and can even result in the introduction of additional survey errors. The loading fluctuations associated with saturation variations in the unsaturated zone may also have implications for other geophysical monitoring techniques, such as geodetic monitoring of ground deformation

    Multitasking Compensatory Saccadic Training Program for Hemianopia Patients: A New Approach With 3-Dimensional Real-World Objects

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    Producción CientíficaPurpose: To examinewhether a noncomputerized multitasking compensatory saccadic training program (MCSTP) for patients with hemianopia, based on a reading regimen and eight exercises that recreate everyday visuomotor activities using threedimensional (3D) real-world objects, improves the visual ability/function, quality of life (QL), and functional independence (FI). Methods: The 3D-MCSTP included four in-office visits and two customized homebased daily training sessions over 12weeks. A quasiexperimental, pretest/posttest study designwas carried out with an intervention group (IG) (n = 20) and a no-training group (NTG) (n = 20) matched for age, hemianopia type, and brain injury duration. Results: The groups were comparable for the main baseline variables and all participants (n = 40) completed the study. The IGmainly showed significant improvements in visual-processing speed (57.34% ± 19.28%; P < 0.0001) and visual attention/retention ability (26.67% ± 19.21%; P < 0.0001), which also were significantly greater (P < 0.05) than in the NTG. Moreover, the IG showed large effect sizes (Cohen’s d) in 75% of the totalQL and FI dimensions analyzed; in contrast to the NTGthat showed negligiblemean effect sizes in 96% of these dimensions. Conclusions: The customized 3D-MCSTP was associated with a satisfactory response in the IG for improving complex visual processing, QL, and FI. Translational Relevance: Neurovisual rehabilitation of patientswith hemianopia seems more efficient when programs combine in-office visits and customized home-based training sessions based on real objects and simulating real-life conditions, than no treatment or previously reported computer-screen approaches, probably because of better stimulation of patients´ motivation and visual-processing speed brain mechanisms

    Tutor and teacher timescapes : lessons from a home-school partnership

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    A partnership project was developed in which parents volunteered to support teachersin training years 1-3 children in computer skills at a primary school in a small, lowsocio-economic community. This article identifies the ways teachers and the &lsquo;tutors&rsquo;(as the volunteers were called) understood the value of the project. &lsquo;Being a teacher&rsquo;and &lsquo;being a volunteer&rsquo; were structured by different forms of social engagement,which in turn influenced the ways individuals were able to work with each other incollaborative processes. We argue that the discursive practices encoded in homeschool-community partnership rhetoric represent ruling-class ways of organising andnetworking that may be incompatible with those of people from low socio-economicbackgrounds. When such volunteers work in schools their attendance may be sporadicand short-term whereas teachers would like &lsquo;reliable&rsquo; ongoing commitment. Thismismatch wrought of teachers&rsquo; and volunteers&rsquo; differing everyday realities needs to beunderstood before useful models for partnerships in disadvantaged communities maybe realised.<br /

    Joint Elastic Side-Scattering Lidar and Raman Lidar Measurements of Aerosol Optical Properties in South East Colorado

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    We describe an experiment, located in south-east Colorado, USA, that measured aerosol optical depth profiles using two Lidar techniques. Two independent detectors measured scattered light from a vertical UV laser beam. One detector, located at the laser site, measured light via the inelastic Raman backscattering process. This is a common method used in atmospheric science for measuring aerosol optical depth profiles. The other detector, located approximately 40km distant, viewed the laser beam from the side. This detector featured a 3.5m2 mirror and measured elastically scattered light in a bistatic Lidar configuration following the method used at the Pierre Auger cosmic ray observatory. The goal of this experiment was to assess and improve methods to measure atmospheric clarity, specifically aerosol optical depth profiles, for cosmic ray UV fluorescence detectors that use the atmosphere as a giant calorimeter. The experiment collected data from September 2010 to July 2011 under varying conditions of aerosol loading. We describe the instruments and techniques and compare the aerosol optical depth profiles measured by the Raman and bistatic Lidar detectors.Comment: 34 pages, 16 figure
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