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A field study was conducted in 2015 and 2016 at the H. Rouse Caffey Rice Research Station near Crowley, Louisiana, to evaluate the interactions of quizalofop and a mixture of propanil plus thiobencarb applied sequentially or mixed to control weedy rice and barnyardgrass. Visual weed control evaluations occurred at 14, 28, and 42 d after treatment (DAT). Quizalofop was applied at 120 g ai ha−1 at 7, 3, and 1 d before and after propanil plus thiobencarb were each applied at 3,360 g ai ha−1. In addition, quizalofop was applied alone and in a mixture with propanil plus thiobencarb at day 0. Control of red rice ‘CL-111’ and ‘CLXL-745’ was greater than 91% when quizalofop was applied alone at day 0, similar to control for quizalofop applied 7, 3, and 1 d prior to propanil plus thiobencarb at all evaluation dates. Control of the same weeds treated with quizalofop plus propanil plus thiobencarb applied in a mixture at day 0 was 70% to 76% at each evaluation date, similar to quizalofop applied 1 or 3 d after propanil plus thiobencarb. A similar trend in control of barnyardgrass by 88% to 97% occurred when quizalofop was applied alone and by 48% to 53% at 14, 28, and 42 DAT when the mixture was used. ‘PVL01’ rough rice yield was 4,060 kg ha−1 when treated with quizalofop alone; however, yield was reduced to 3,180 kg ha−1 when it was treated with quizalofop mixed with propanil plus thiobencarb at day 0, similar to PVL01 rice treated with quizalofop 1 or 3 d following the propanil plus thiobencarb application.
A field study was conducted during the 2016 and 2017 crop seasons at the LSU AgCenter H. Rouse Caffey Rice Research Station to evaluate weed control and rice yield after quizalofop-p-ethyl applications in water-seeded coenzyme A carboxylase (ACCase)–resistant ‘PVLO1’ long-grain rice production utilizing different flood systems, application timings, and quizalofop rates. The initial application of quizalofop was applied at five timings beginning when ‘PVLO1’ rice was at the coleoptile stage (PEG) through the one- to two-tiller stage. A total quizalofop rate of 240 g ai ha–1 was split into two applications: 97 followed by 143 g ha–1 or 120 followed by 120 g ai ha–1 in both pinpoint and delayed flood water-seeded management systems. A second quizalofop application was applied 14 d after initial treatment (DAIT). At 14 DAIT, a reduction in control of barnyardgrass and red rice was observed by delaying the initial quizalofop application to the two- to four-tiller stage compared with rice treated at earlier growth stages. At 42 DAIT, control of barnyardgrass was 94% to 96%, and red rice was 98% following the second application of quizalofop, regardless of initial application timing. Rice treated with quizalofop at the PEG and two- and three-leaf stage resulted in a rice height of 104 cm at harvest compared with 96 to 100 cm when the initial application of quizalofop was delayed to later growth stages. Applying the initial application of quizalofop to rice at the PEG timing in the pinpoint or the delayed flood system resulted in a total gross value per hectare of $450 and $590, respectively. Within each flood system, delaying the initial application of quizalofop to the one- to two-tiller stage resulted in a gross per-hectare value reduction of $100 ha-1 in the pinpoint flood and $110 ha-1 in the delayed flood.
Acetyl co-enzyme A carboxylase (ACCase)-resistant rice allows quizlaofop-p-ethyl to be applied as a POST control of troublesome grass weeds. A field study was conducted in 2017 and 2018 at the H. Rouse Caffey Rice Research Station near Crowley, LA, to evaluate the influence of a crop oil concentrate (COC), a silicon-based surfactant plus a nitrogen source (SNS), or a high-concentrate COC (HCOC) in overcoming the grass weed control antagonism of quizalofop-p-ethyl when mixed with bispyribac-Na. Quizalofop-p-ethyl was applied at 120 g ai ha−1, bispyribac-Na was applied at 34 g ai ha−1, and all adjuvants were applied at 1% vol/vol. Antagonistic interactions were observed at 14 d after treatment (DAT) when quizalofop-p-ethyl was mixed with bispyribac-Na with no adjuvant for control of barnyardgrass, the non–ACCase-tolerant rice cultivars ‘CL-111’ and ‘CLXL-745’, and red rice. At 14 DAT, antagonism of quizalofop-p-ethyl for control of barnyardgrass was observed when mixed with bispyribac-Na plus COC, SNS, or HCOC, with an observed control of 43%, 63%, and 86%, respectively, compared with an expected control of 95% for quizalofop-p-ethyl alone. However, the antagonism of quizalofop-p-ethyl when mixed with bispyribac-Na plus HCOC for barnyardgrass control at 14 DAT was overcome by 28 DAT, with an observed control of 91%, compared with an expected control of 97%. Synergistic or neutral interactions were observed at 14 and 28 DAT when COC, SNS, or HCOC was added to a mixture of quizalofop-p-ethyl plus bispyribac-Na for CL-111, CLXL-745, and red rice control. According to the results of this study, HCOC is the most effective adjuvant for quizalofop-p-ethyl and bispyribac-Na mixtures for control of weedy rice and barnyardgrass.
Six on-farm studies determined the effects of a rolled rye cover crop, herbicide program, and planting technique on cotton stand, weed control, and cotton yield in Georgia. Treatments included: (1) rye drilled broadcast with 19-cm row spacing and a broadcast-herbicide program (2) rye drilled with a 25-cm rye-free zone in the cotton row and a broadcast-herbicide program (3) rye drilled with a 25-cm rye-free zone in the cotton row with PPI and PRE herbicides banded in the cotton planting row, and (4) no cover crop (i.e., weedy cover) with broadcast herbicides. At two locations, cotton stand was lowest with rye drilled broadcast; at these sites the rye-free zone maximized stand equal to the no-cover system. At a third location, cover crop systems resulted in greater stand, due to enhanced soil moisture preservation compared with the no-cover system. Treatments did not influence cotton stand at the other three locations and did not differ in the control of weeds other than Palmer amaranth at any location. Treatments controlled Palmer amaranth equally at three locations; however, differences were observed at the three locations having the greatest glyphosate-resistant plant densities. For these locations, when broadcasting herbicides, Palmer amaranth populations were reduced 82% to 86% in the broadcast rye and rye-free zone systems compared with the no-cover system at harvest. The system with banded herbicides was nearly 21 times less effective than the similar system broadcasting herbicides. At these locations, yields in the rye broadcast and rye-free zone systems with broadcast herbicides were increased 9% to 16% compared with systems with no cover or a rye-free zone with PPI and PRE herbicides banded. A rolled rye cover crop can lessen weed emergence and selection pressure while improving weed control and cotton yield, but herbicides should be broadcast in fields heavily infested with glyphosate-resistant Palmer amaranth.
A study was conducted in 2017 and 2018 at the H. Rouse Caffey Rice Research Station near Crowley, LA, to evaluate quizalofop at 120 g ai ha−1 applied independently or in a mixture with clomazone, pendimethalin, clomazone plus pendimethalin, or a prepackaged mixture of clomazone plus pendimethalin when PVLO1 rice reached the two- to three-leaf stage. A second application of quizalofop at 120 g ha−1 was applied 21 d after the initial application. At 7 days after treatment (DAT), antagonism of quizalofop occurred when mixed with clomazone at 334 g ai ha−1, clomazone at 334 g ai ha−1 plus pendimethalin at 810 g ai ha−1, or a prepackaged mixture of clomazone plus pendimethalin at 334 plus 810 g ai ha−1, respectively, when applied to barnyardgrass. At 7 DAT, a neutral interaction occurred with a mixture of quizalofop plus pendimethalin at 810 g ha−1. These data indicate the antagonism of quizalofop was overcome at 14, 28, and 42 DAT with a neutral interaction for barnyardgrass control, 94% to 98%, with all herbicide mixtures evaluated. A neutral interaction occurred for CL-111, CLXL-745, and red rice control when treated with all the herbicide mixtures evaluated across all evaluation dates. Rice yield decreased when not treated with the initial quizalofop application.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
Background: Biallelic variants in POLR1C are associated with POLR3-related leukodystrophy (POLR3-HLD), or 4H leukodystrophy (Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism), and Treacher Collins syndrome (TCS). The clinical spectrum of POLR3-HLD caused by variants in this gene has not been described. Methods: A cross-sectional observational study involving 25 centers worldwide was conducted between 2016 and 2018. The clinical, radiologic and molecular features of 23 unreported and previously reported cases of POLR3-HLD caused by POLR1C variants were reviewed. Results: Most participants presented between birth and age 6 years with motor difficulties. Neurological deterioration was seen during childhood, suggesting a more severe phenotype than previously described. The dental, ocular and endocrine features often seen in POLR3-HLD were not invariably present. Five patients (22%) had a combination of hypomyelinating leukodystrophy and abnormal craniofacial development, including one individual with clear TCS features. Several cases did not exhibit all the typical radiologic characteristics of POLR3-HLD. A total of 29 different pathogenic variants in POLR1C were identified, including 13 new disease-causing variants. Conclusions: Based on the largest cohort of patients to date, these results suggest novel characteristics of POLR1C-related disorder, with a spectrum of clinical involvement characterized by hypomyelinating leukodystrophy with or without abnormal craniofacial development reminiscent of TCS.
A study was conducted at the Louisiana State University Agricultural Center’s H. Rouse Caffey Rice Research Station in 2017 and 2018 to evaluate a prepackaged mixture of clomazone plus pendimethalin applied delayed preemergence (DPRE) or POST within an herbicide residual overlay with saflufenacil, clomazone, or quinclorac. POST applications included penoxsulam or halosulfuron in combination with the second residual application. No differences were observed in barnyardgrass control (92% to 98%) at 14 days after treatment (DAT). At 42 DAT, barnyardgrass treated with clomazone plus pendimethalin in combination with either clomazone or quinclorac at either timing was controlled 95% to 96%. However, when saflufenacil was applied PRE, regardless of the POST herbicide or when saflufenacil was applied POST with halosulfuron, barnyardgrass control was reduced to 78% to 81%, compared with 95% to 96% with the control with all other residual combinations. Yellow nutsedge and rice flatsedge control increased when treated with halosulfuron compared with penoxsulam across all evaluation dates. At 28 and 42 DAT, texasweed treated with saflufenacil PRE, regardless of POST applications, was controlled 83% and 87%, respectively, and this was greater control than provided by clomazone or quinclorac applied PRE regardless of POST herbicide program.
A glasshouse study was conducted on the Louisiana State University campus in Baton Rouge, LA, to evaluate the control of brook crowngrass, rice cutgrass, southern watergrass, and water paspalum. Florpyrauxifen-benzyl was applied at 30 g ai ha−1 to each grass species at the 3- to 4-leaf or 1- to 2-stolon stage of growth. Brook crowngrass treated with florpyrauxifen was controlled 71% at 21 d after treatment. Southern watergrass and water paspalum control did not exceed 56% and 36%, respectively, across all evaluations. Rice cutgrass treated with florpyrauxifen did not reach 15% control. Plants treated with florpyrauxifen, except rice cutgrass, displayed reduction in leaf number, stolon number, plant height, and plant fresh weight. These results indicate florpyrauxifen-benzyl can help manage a brook crowngrass infestation and suppress southern watergrass. However, florpyrauxifen-benzyl has little to no activity on water paspalum and rice cutgrass, and other management options should be employed if these weeds are present.
A field study was conducted in 2015 and 2016 near Crowley, LA, to evaluate antagonistic, synergistic, or neutral interactions of quizalofop when mixed with contact herbicides labeled for use in rice production. Quizalofop was applied at 120 g ai ha−1. Mixture herbicides included bentazon at 1,050 g ai ha−1, carfentrazone at 18 g ai ha−1, propanil at 3,360 g ai ha−1, saflufenacil at 25 g ai ha−1, and thiobencarb at 3,360 g ai ha−1. A second application of quizalofop at 120 g ha−1 was made at 28 d after the initial application (DAIT) to evaluate control of weeds escaping the initial treatment. At 14 and 28 DAIT, red rice, ‘CLXL-745’, and ‘CL-111’ treated with quizalofop plus propanil indicated an antagonistic response with an observed control of 69% to 71% compared with an expected control of 92% to 94%. Barnyardgrass treated with the same mixture also indicated an antagonistic response at 14 and 28 DAIT with an observed control of 16% compared with an expected control of 94%. Barnyardgrass treated with quizalofop plus saflufenacil indicated an antagonistic response at 14 DAIT; however, the same mixture produced a neutral response by 28 DAIT. In addition, a second application of quizalofop was not able to overcome the antagonism observed with a quizalofop plus propanil mixture at 14 and 28 DAIT for red rice, CLXL-745, CL-111, or barnyardgrass control. Quizalofop mixed with carfentrazone or thiobencarb produced a neutral response for all weeds evaluated at each evaluation date.
We provide the first in situ measurements of antenna element beam shapes of the Murchison Widefield Array. Most current processing pipelines use an assumed beam shape, which can cause absolute and relative flux density errors and polarisation ‘leakage’. Understanding the primary beam is then of paramount importance, especially for sensitive experiments such as a measurement of the 21-cm line from the epoch of reionisation, where the calibration requirements are so extreme that tile to tile beam variations may affect our ability to make a detection. Measuring the primary beam shape from visibilities is challenging, as multiple instrumental, atmospheric, and astrophysical factors contribute to uncertainties in the data. Building on the methods of Neben et al. [Radio Sci., 50, 614], we tap directly into the receiving elements of the telescope before any digitisation or correlation of the signal. Using ORBCOMM satellite passes we are able to produce all-sky maps for four separate tiles in the XX polarisation. We find good agreement with the beam model of Sokolowski et al. [2017, PASA, 34, e062], and clearly observe the effects of a missing dipole from a tile in one of our beam maps. We end by motivating and outlining additional on-site experiments.
We describe the motivation and design details of the ‘Phase II’ upgrade of the Murchison Widefield Array radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the Murchison Widefield Array in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing array core. These new tiles enhance the surface brightness sensitivity of the array and will improve the ability of the Murchison Widefield Array to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ∼3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u, v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of Murchison Widefield Array continuum images. The upgrade retains all of the features that have underpinned the Murchison Widefield Array’s success (large field of view, snapshot image quality, and pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies.
In Cameroon, there is a national programme engaged in the control of schistosomiasis and soil-transmitted helminthiasis. In certain locations, the programme is transitioning from morbidity control towards local interruption of parasite transmission. The volcanic crater lake villages of Barombi Mbo and Barombi Kotto are well-known transmission foci and are excellent context-specific locations to assess appropriate disease control interventions. Most recently they have served as exemplars of expanded access to deworming medications and increased environmental surveillance. In this paper, we review infection dynamics through time, beginning with data from 1953, and comment on the short- and long-term success of disease control. We show how intensification of local control is needed to push towards elimination and that further environmental surveillance, with targeted snail control, is needed to consolidate gains in preventive chemotherapy as well as empower local communities to take ownership of interventions.
A glasshouse study was established at Louisiana State University campus in Baton Rouge, LA, to evaluate the control of fall panicum and Nealley’s sprangletop treated with florpyrauxifen-benzyl. Florpyrauxifen was applied at 30 g ai ha–1 to each grass species at the three- to four-leaf and one- to two-tiller stages of growth. At 21 d after treatment (DAT), fall panicum control was 91% when treated with florpyrauxifen at the three- to four-leaf stage, and Nealley’s sprangletop control was 78% to 82%, regardless of application timing 21 DAT. Leaf number, tiller number, plant height, and plant fresh weight were reduced when fall panicum and Nealley’s sprangletop were treated with florpyrauxifen. This information can be useful for developing weed management strategies with this herbicide for rice production, and it provides an additional mode of action to help manage and/or delay the development of herbicide-resistant weeds.
Two field studies were conducted in Louisiana to determine the impact of Nealley’s sprangletop on rough rice yield under multiple environments in 2014, 2015, and 2016. The first study evaluated optimal timings of Nealley’s sprangletop removal for optimizing rough rice yields. The second study evaluated the impact of Nealley’s sprangletop densities on rough rice yield. Nealley’s sprangletop was removed with applications of fenoxaprop at 122 g ai ha–1 at 7, 14, 21, 28, 35, and 42 d after emergence (DAE). Nealley’s sprangletop removal at 7 and 14 DAE resulted in higher rough rice yields of 7,880 and 6,960 kg ha–1, respectively, when compared with the rice from the season-long Nealley’s sprangletop competition with a 6,040 kg ha-1 yield. Delaying herbicide application from 7 DAE to 42 DAE resulted in a yield loss of 1,740 kg ha–1. Over the 35-d delay in application, rough rice yield loss from Nealley’s sprangletop interference was equivalent to 50 kg ha–1 d–1. Nealley’s sprangletop densities were established at 1, 3, 7, 13, and 26 plants m–2 by transplanting Nealley’s sprangletop when rice reached the one- to two-leaf stage. At Nealley’s sprangletop densities of 1 to 26 plants m–2, rough rice yields were reduced 10 to 270 kg ha–1, compared with the rice from weed-free plots. Based on regression analysis, Nealley’s sprangletop densities of 1, 35, 70, and 450 plants m–2 reduced rough rice yield 0.14%, 5%, 10%, and 50%, respectively.
Outbreaks of Old World cutaneous leishmaniasis (CL) have significantly increased due to the conflicts in the Middle East, with most of the cases occurring in resource-limited areas such as refugee settlements. The standard methods of diagnosis include microscopy and parasite culture, which have several limitations. To address the growing need for a CL diagnostic that can be field applicable, we have identified five candidate neoglycoproteins (NGPs): Galα (NGP3B), Galα(1,3)Galα (NGP17B), Galα(1,3)Galβ (NGP9B), Galα(1,6)[Galα(1,2)]Galβ (NGP11B), and Galα(1,3)Galβ(1,4)Glcβ (NGP1B) that are differentially recognized in sera from individuals with Leishmania major infection as compared with sera from heterologous controls. These candidates contain terminal, non-reducing α-galactopyranosyl (α-Gal) residues, which are known potent immunogens to humans. Logistic regression models found that NGP3B retained the best diagnostic potential (area under the curve from receiver-operating characteristic curve = 0.8). Our data add to the growing body of work demonstrating the exploitability of the human anti-α-Gal response in CL diagnosis.
Adult schistosomes live in the blood vessels and cannot easily be sampled from humans, so archived miracidia larvae hatched from eggs expelled in feces or urine are commonly used for population genetic studies. Large collections of archived miracidia on FTA cards are now available through the Schistosomiasis Collection at the Natural History Museum (SCAN). Here we describe protocols for whole genome amplification of Schistosoma mansoni and Schistosome haematobium miracidia from these cards, as well as real time PCR quantification of amplified schistosome DNA. We used microgram quantities of DNA obtained for exome capture and sequencing of single miracidia, generating dense polymorphism data across the exome. These methods will facilitate the transition from population genetics, using limited numbers of markers to population genomics using genome-wide marker information, maximising the value of collections such as SCAN.
A field study was conducted in 2015 and 2016 at the H. Rouse Caffey Rice Research Station (RRS) to evaluate antagonistic, synergistic, or neutral interactions of quizalofop when mixed with ALS-inhibiting herbicides labeled in rice production. Quizalofop was applied at 120 g ai ha−1. Mixture herbicides included penoxsulam at 40 g ai ha−1, penoxsulam+triclopyr at 352 g ai ha−1, halosulfuron at 53 g ai ha−1, bispyribac at 34 g ai ha−1, orthosulfamuron+halosulfuron at 94 g ai ha−1, orthosulfamuron+quinclorac at 491 g ai ha−1, imazosulfuron at 211 g ai ha−1, and bensulfuron at 43 g ai ha−1. All ALS herbicides mixed with quizalofop indicated antagonistic responses for red rice, CL-111, CLXL 745, or barnyardgrass control at either 14 or 28 days after treatment (DAT). At 28 DAT, quizalofop mixed with penoxsulam or bispyribac controlled barnyardgrass 34 to 38%, compared with an expected control of 97%. In addition, these same mixtures controlled red rice, CL-111, and CLXL-745 61 to 67% at 28 DAT compared with an expected control of 96 to 97%. A second application of quizalofop at 120 g ha−1 was applied at 28 DAT. At 42 DAT, neutral responses were indicated for all mixtures except with quizalofop mixed with penoxsulam containing products.