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1

Arnaud-Freddy, Yapi. "Constraining weeds in okra cultivation and farmer management of weeds in South-East of Côte d'Ivoire." Journal of Biodiversity and Environmental Sciences (JBES) 25, no. 4 (2024): 71–78. https://doi.org/10.5281/zenodo.15510654.

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This study was carried out among okra growers in the La M&eacute; region, with the aim of identifying farmers&rsquo; weed management practices and the main weeds present in the fields. Using a questionnaire coupled with a floristic inventory in each field, the agrotechnical characteristics of the farms and the main weed species were determined. The results show that 94.67% of the farmers surveyed use herbicides and 67.33% use insecticides. Almost all the herbicides used were total herbicides, applied before sowing. 68.67% of growers carry out three weed control operations per production cycle, and the weed control method most frequently used is chemical weed control combined with manual weed control. The inventory of major weeds reveals that 16 species are a constraint for the crop and 7 of them are cited with a high frequency. These were&nbsp;<em>Panicum maximum</em>,&nbsp;<em>Chromolaena odorata</em>,&nbsp;<em>Ageratum conyzoides</em>,&nbsp;<em>Mimosa pudica</em>,&nbsp;<em>Panicum laxum</em>,&nbsp;<em>Croton hirtus</em>&nbsp;and&nbsp;<em>Centrosema pubescens</em>. The floristic surveys showed that the constraining weeds come from four major botanical families: Asteraceae (37.5%), Poaceae (25%), Euphorbiaceae (18.75%) and Fabaceae (18.75%). Hemicryptophytes (41.84%) and Nanophanerophytes (34.05%) are the two biological types that contain the most constraining weeds. This study is a fundamental step towards initiating an effective weed management strategy for okra. The results of this study will make it possible to propose effective ways of controlling these weeds. These include reducing weeds to a tolerable nuisance threshold for the crop, setting up a trial to determine the critical weed period, and establishing crop rotations and combinations. published by the&nbsp;<strong> Journal of Biodiversity and Environmental Sciences (JBES)</strong>
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YAPI, Arnaud-Freddy, Arsène GUE, Ahia Christine Florence KPLA, and Maxime N’tapké Kama BORAUD. "Abundance and Partial Harmfulness Index (PHI) of Weeds in Plantain (Musa paradisiaca L., Musaceae) in Mé Region, South-East Côte d'Ivoire." Asian Journal of Biology 21, no. 6 (2025): 80–91. https://doi.org/10.9734/ajob/2025/v21i6515.

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Poor weed management can result in additional costs that can be estimated at over 35%. Determining of the most troublesome weeds is becoming an essential part of effective weed control. A study was therefore carried out in the south-east of Côte d'Ivoire, in plantain plantations, to identify abundant weeds and assess their potential for causing damage. Two approaches were used. The first one consisted in carrying out a survey of plantain growers and the second in carrying out floristic surveys in plantain fields. To do this, the degree of infestation and the Partial Harmfulness Index of the major weeds in these works were analysed. Growers have identified 19 weeds that are difficult to control. In terms of weed flora, 152 species divided into 115 genera belonging to 47 families were recorded. The infestation diagram distinguished 20 major weeds, of which Panicum laxum is the most aggressive (FC = 80.28%; ADaverage= 1.55). The Partial Harmfulness Index (PHI) determined five (5) potentially harmful weeds (PHI ≥ 1000). After cross-referencing the two lists of constraining and major weeds (survey and floristic survey), there is floristic homogeneity, with 25 constraining and major weeds in this study. With a view to better weed control in banana cultivation in the Mé region, growers should take into account the most abundant and constraining weeds in order to reduce yield losses.
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GHAMARI, Hossein. "Weed Interference Effects on Leaves, Internode and Harvest Index of Dry Bean (Phaseolus vulgaris L.)." Notulae Scientia Biologicae 7, no. 1 (2015): 111–15. http://dx.doi.org/10.15835/nsb719415.

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The development of appropriate weed management strategies and efficient use of herbicides relies upon understanding weed-crop interactions. A field study was carried out to assess the effect of weed interference on leaves, internode and harvest index of dry bean (Phaseolus vulgaris L.). The experiment was established under a randomized complete block design with two types of weed interference treatments: plots with weeds and plots without weeds at different time intervals (0, 10, 20, 30, 40 and 50 days after crop emergence). The sigmoid Boltzmann model was used to quantify the crop traits as influenced by weed interference. Prolonged delays in weed removal reduced gradually the number of leaves of the crop. Weed interference decreased dry weight of leaves as well, so that the lowest value of it (33.49 g plant-1) was observed in full season during weed-infested treatment. Infestation of weeds affected the length of the crop internodes. While the weed interference duration increased, the length of the internodes decreased. Harvest index was also sensitive to weed competition. As the crop was kept weed-infested from the emergence for increasing periods of time, harvest index decreased to a value of 28.01%. A significant negative correlation between total biomass of weeds and dry bean traits (number of leaves, leaves dry weight, internode length and harvest index) was observed. Therefore, weeds are able to adversely affect dry bean growth through constraining environmental resources and impairing leaves as the photosynthetic areas.
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N.D, Zatale, Chandurkar R.S, Shinde M.P, et al. "RNAi in Plant Protection: A Targeted Approach for Insect Pest Suppression." Agriculture Association of Textile Chemical and Critical Reviews 13, no. 2 (2025): 187–91. https://doi.org/10.21276/aatccreview.2025.13.02.186.

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The biggest challenge faced by humanity in the 21 st is how to increase crop yields in a profitable, efficient, and sustainable way. There are several issues constraining agricultural productivity, such as damage by insect pests, diseases, and weeds. Currently, chemical pesticides remain the major approach used for suppressing insect pests owing to their well-controlled effect. Unfortunately, the excessive application of chemical pesticides has caused some serious problems threatening the environment and human health. RNAi is a post-transcriptional gene silencing mechanism initiated by the introduction of double-stranded RNA (dsRNA) into a cell. This knockdown mechanism of gene by dsRNA is known as RNA interference (RNAi) in animals and post-transcriptional gene silencing in plants. The basic dsRNA delivery methods include microinjection, feeding, and soaking. To improve dsRNA delivery, various new technologies, including cationic liposome–assisted, nanoparticle-enabled, symbiont-mediated, and plant-mediated deliveries, have been developed. Chemically synthesized and modified siRNA corresponding to P. xylostellaAChE genes cause significant mortality of the insect both under laboratory and field conditions, which provides a novel strategy to control P. xylostella and to develop bio-pesticides based on RNA interference technology. However, the widespread adoption of RNAi for insect pest management faces several key challenges, including the high cost of dsRNA synthesis, the need for efficient delivery to the target site, concerns over off-target and non-target effects, and the potential development of resistance. Furthermore, innovative approaches such as cell-free RNAi production and nanotechnology-mediated RNAi transfer offer promising solutions to challenges like high synthesis costs and efficient dsRNA delivery, paving the way for the practical application of RNAi in sustainable insect pest management.
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Fernández-Aparicio, Mónica, Lidia del Moral, Stéphane Muños, Leonardo Velasco, and Begoña Pérez-Vich. "Genetic and physiological characterization of sunflower resistance provided by the wild-derived OrDeb2 gene against highly virulent races of Orobanche cumana Wallr." Theoretical and Applied Genetics 135, no. 2 (2021): 501–25. http://dx.doi.org/10.1007/s00122-021-03979-9.

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Abstract Key message OrDeb2 confers post-attachment resistance to Orobanche cumana and is located in a 1.38 Mbp genomic interval containing a cluster of receptor-like kinase and receptor-like protein genes with nine high-confidence candidates. Abstract Sunflower broomrape is a holoparasitic angiosperm that parasitizes on sunflower roots, severely constraining crop yield. Breeding for resistance is the most effective method of control. OrDeb2 is a dominant resistance gene introgressed into cultivated sunflower from a wild-related species that confers resistance to highly virulent broomrape races. The objectives of this study were as follows: (i) locate OrDeb2 into the sunflower genome and determine putative candidate genes and (ii) characterize its underlying resistance mechanism. A segregating population from a cross between the sunflower resistant line DEB2, carrying OrDeb2, and a susceptible line was phenotyped for broomrape resistance in four experiments, including different environments and two broomrape races (FGV and GTK). This population was also densely genotyped with microsatellite and SNP markers, which allowed locating OrDeb2 within a 0.9 cM interval in the upper half of Chromosome 4. This interval corresponded to a 1.38 Mbp genomic region of the sunflower reference genome that contained a cluster of genes encoding LRR (leucine-rich repeat) receptor-like proteins lacking a cytoplasmic kinase domain and receptor-like kinases with one or two kinase domains and lacking an extracellular LRR region, which were valuable candidates for OrDeb2. Rhizotron and histological studies showed that OrDeb2 determines a post-attachment resistance response that blocks O. cumana development mainly at the cortex before the establishment of host-parasite vascular connections. This study will contribute to understand the interaction between crops and parasitic weeds, to establish durable breeding strategies based on genetic resistance and provide useful tools for marker-assisted selection and OrDeb2 map-based cloning.
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MUNYULI, Théodore, Justin OMBENI, Bienfait BASHI MUSHAGALUSA, Arcadius KUBUYA, Alain IRENGE, and Gentil KIWAF HERADI. "DIAGNOSTIC OF THE CURRENT LIVELIHOOD EVOLUTION, FARMING PRACTICES, PRODUCTION CONSTRAINTS, POST-HARVEST PROCESSING, TRADING AND VALUE-CHAIN SYSTEMS OF SWEETPOTATO IN NORTH-KIVU PROVINCE, EASTERN OF DRCONGO." International Journal of Agriculture, Environment and Bioresearch 07, no. 06 (2022): 11–93. http://dx.doi.org/10.35410/ijaeb.2022.5778.

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Although in many countries of Sub-Sahara Africa, sweet potato has been found to be very important for food security for farmers who depended on it for their livelihood, little documentation on the production constraints, preferences for sweetpotato genotypes by farmers, pre- and post-harvest handling and value chain issues were available for North-Kivu province. Hence, a survey assessment was conducted (March-December 2021) in major sweetpotato growing territories in North-Kivu province. Data was collected through field visits, semistructured interviews, focus group discussions and field observations after structured questionnaire have been administered to farmers. Descriptive statistics were applied to analyze the data. The results indicated that sweetpotato is grown by rural households for food and cash, and women play a major role in cultivating the crop. The crop was cultivated on small plots, mainly in upland areas, during the rainy season and sometimes in valley bottoms during dry season. Most farmers provide their own planting materials or obtained vines free from neighbours. Vines were usually planted on mounds. Ridges were used in highland areas in lieu of mounds as a way to control soil erosion/land slide impacts. Sweetpotato is commonly solecropped, although it is occasionally intercropped with beans, maize, banana, and other crops. Key attributes for maintenance of varieties were access to healthy planting material availability and distribution, tolerance abiotic stresses, resistance to biotic stresses, good taste and high root yield , early maturity, cookability, low perishability during storage. Piecemeal harvesting was common except when larger quantities are harvested for sale. During the harvest period, people consume sweetpotatoes every day and sometimes for every meal. Peeling &amp; boiling or steaming is the most common method of preparation. Pests and diseases were reported to be associated with severe and high yield loss although incidence of pests and diseases were of high seasonal variations. The overall identified factors constraining productivity included shortage of land and planting materials, landrace low yield, some variety high sensitivity to weeds, diseases and insect pests aggressions, inaccessibility to financial credits. Post-harvest and value chain constraints included: high labour and transport costs, poor access to markets &amp; low market prices, inaccessibility to improved varieties, a lack of knowledge on processing and equipment, packaging, marketing and transportation problems, inadequate extension services and postharvest losses. Farmers indicated that flood and landslide/soil erosion were serious abiotic stresses. The result showed that age, education level of household head, land and household sizes, input costs, livestock ownership, access to market information and to financial credit or extension services, output and sales revenue may have a significant impact on outcome and affect household gross margin. Thus, enhancing farmers’ access to market information, boosting the production and productivity of the crop through better extension services and infrastructures, awareness creation on gender balanced market engagement and improvement in transportation facilities are the critical points that should get policy attentions in the study area. Results of this study can serve as a baseline reference for strategic breeding and other interventions to develop sweetpotato varieties according to the needs of the farmers.
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Henry, Georgia A., and John R. Stinchcombe. "G-matrix stability in clinally diverging populations of an annual weed." Evolution 77, no. 1 (2022): 49–62. http://dx.doi.org/10.1093/evolut/qpac005.

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Abstract How phenotypic and genetic divergence among populations is influenced by the genetic architecture of those traits, and how microevolutionary changes in turn affect the within-population patterns of genetic variation, are of major interest to evolutionary biology. Work on Ipomoea hederacea, an annual vine, has found genetic clines in the means of a suite of ecologically important traits, including flowering time, growth rate, seed mass, and corolla width. Here we investigate the genetic (co)variances of these clinally varying traits in two northern range-edge and two central populations of I. hederacea to evaluate the influence of the genetic architecture on divergence across the range. We find (1) limited evidence for clear differentiation between Northern and Southern populations in the structure of G, suggesting overall stability of G across the range despite mean trait divergence and (2) that the axes of greatest variation (gmax) were unaligned with the axis of greatest multivariate divergence. Together these results indicate the role of the quantitative genetic architecture in constraining evolutionary response and divergence among populations across the geographic range.
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Brinkhoff, James, John Hornbuckle, and Jan Barton. "Assessment of Aquatic Weed in Irrigation Channels Using UAV and Satellite Imagery." Water 10, no. 11 (2018): 1497. http://dx.doi.org/10.3390/w10111497.

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Irrigated agriculture requires high reliability from water delivery networks and high flows to satisfy demand at seasonal peak times. Aquatic vegetation in irrigation channels are a major impediment to this, constraining flow rates. This work investigates the use of remote sensing from unmanned aerial vehicles (UAVs) and satellite platforms to monitor and classify vegetation, with a view to using this data to implement targeted weed control strategies and assessing the effectiveness of these control strategies. The images are processed in Google Earth Engine (GEE), including co-registration, atmospheric correction, band statistic calculation, clustering and classification. A combination of unsupervised and supervised classification methods is used to allow semi-automatic training of a new classifier for each new image, improving robustness and efficiency. The accuracy of classification algorithms with various band combinations and spatial resolutions is investigated. With three classes (water, land and weed), good accuracy (typical validation kappa &gt;0.9) was achieved with classification and regression tree (CART) classifier; red, green, blue and near-infrared (RGBN) bands; and resolutions better than 1 m. A demonstration of using a time-series of UAV images over a number of irrigation channel stretches to monitor weed areas after application of mechanical and chemical control is given. The classification method is also applied to high-resolution satellite images, demonstrating scalability of developed techniques to detect weed areas across very large irrigation networks.
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Kromm, Arne, Thomas Kannengiesser, Jens Altenkirch, and Jens Gibmeier. "Residual Stresses in Multilayer Welds with Different Martensitic Transformation Temperatures Analyzed by High-Energy Synchrotron Diffraction." Materials Science Forum 681 (March 2011): 37–42. http://dx.doi.org/10.4028/www.scientific.net/msf.681.37.

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Low Transformation Temperature (LTT) alloys were developed in order to control the residual stress development by the martensitic phase transformation already during cooling of the weld metal. The positive effect of such LTT alloys on the mitigation of detrimental tensile residual stresses during welding has already been confirmed on the basis of individual laboratory tests. Within the current project it was experimentally investigated whether the phase transformation mechanisms are effective under increased restraint due to multi-pass welding of thicker specimens. The local residual stress depth distribution was analyzed non-destructively for V-type welds processed by arc welding using energy dispersive synchrotron X-ray diffraction (EDXRD). The use of high energy (20 keV to 150 keV) EDXRD allowed for the evaluation of diffraction spectra containing information of all contributing phases. As the investigated LTT alloy contains retained austenite after welding, this phase was also considered for stress analysis. The results show in particular how the constraining effect of increased thickness of the welded plates and additional deposited weld metal influences the level of the residual stresses in near weld surface areas. While the longitudinal residual stresses were reduced in general, in the transition zone from the weld to the heat-affected zone (HAZ) compressive residual stresses were found.
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Ferreira, Susana, Fátima Oliveira, Francisco Gomes da Silva, et al. "Assessment of Factors Constraining Organic Farming Expansion in Lis Valley, Portugal." AgriEngineering 2, no. 1 (2020): 111–27. http://dx.doi.org/10.3390/agriengineering2010008.

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Organic farming can play an important role in rural development and food production, by reinforcing the trend toward sustainable agriculture and its purpose of ecosystem conservation. The agribusiness of organic farming is particularly relevant in family farming, given the labor availability and the short marketing circuits. The innovative techniques of organic farming, namely with soil fertility, weed and pest control, opens a wide range of possibilities in its development and extension. The expectation of organic farming profitability in small-scale family farming, supported by known successful examples, were the theme of a field study on Lis Valley Irrigation District to assess the constraints to its expansion in order to outline the procedures for the acquisition of technical knowledge, the adaptation of technologies, the support for the conversion of production models, and the specialized training of farmers for action. Results revealed that the: (i) farmer’s land structure, (ii) their mature age, (iii) low education level, and (iv) markets, are the main constrains for organic farming development. Furthermore, other uncertainties were identified, namely: (i) the certification process, (ii) the knowledge of new technologies, especially of crop protection, and (iii) the marketing problems to guaranteeing profitability. This study concludes that organic farming has significant potential for development in the Lis Valley and that the efforts and resources of the various stakeholders, namely the state, need to be harmonized to deliver effective support to farmers to promote organic farming that prioritizes: (i) rural development policies, (ii) supporting land restructuring, (iii) modernization of irrigation, (iv) stimulation of young farmers, (v) conversion and implementation of innovative technologies, (vi) the organization of farmers for better productive efficiency, and (vii) to facilitate market access.
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Bhardwaj, Piyush, Jaspreet Kaur, Charu Gera, and Manoj Malik. "Effect of mCIMT with and without interval on hand in patient suffering from stroke." Romanian Journal of Neurology 20, no. 1 (2021): 57–65. http://dx.doi.org/10.37897/rjn.2021.1.8.

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Introduction. Paresis of hand has severe impact on the life of the stroke patients. Modified constrained induced movement therapy (mCIMT) can be used to treat the involved limb of the patient. It involves constraining of functional hand and increasing the activity of paretic hand which overcomes the “learned disuse” that develops following stroke but the constraining also creates difficulties for the patient and reduces his/her compliance to the treatment. Hence this trial aims to study the effect of mCIMT with and without interval to see if providing relaxation in between the treatment would be able to produce similar effect as mCIMT without interval protocol. Matgerial and methods. 44 patients were recruited in the study and were divided in to three groups: mCIMT without interval (n = 18), mCIMT with interval (n = 16) and control group (n = 10). Participants in three groups were examined for pain and functionality of hand through Patient rated wrist hand evaluation score and Box and Block test at pre and post intervention. The intervention was given for 6 days/week for two weeks. Therapy time was 2 hours and constrain was for 6 hours a day. Clinical trial registration number -CTRI/2019/12/022547. Results. No baseline differences were found in between the three groups. There was significant increase in box and block test score and significant decrease in PRWHE score in pre and post treatment readings for with and without interval mCIMT but non-significant changes in PRWHE score and box and block test were seen in control group. Conclusion. Both interval and without interval mCIMT was effective. Interval mCIMT was seen to be more comfortable than without interval mCIMT for the patient.
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Yaqoob, Tahir, Kendrah D. Murphy, and Yuichi Terashima. "An accretion disk laboratory in the Seyfert 1.9 galaxy NGC 2992." Proceedings of the International Astronomical Union 2, S238 (2006): 123–26. http://dx.doi.org/10.1017/s1743921307004826.

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AbstractOver twenty five years of X-ray observations of the Seyfert 1.9 galaxy NGC 2992 show that it is a promising test-bed for severely constraining accretion disk models. The previous interpretation of the historical activity of NGC 2992 in terms of the accretion disk slowly becoming dormant over many years and then ‘re-building’ itself is not supported by new data. A recent year-long monitoring campaign with RXTE showed that the X-ray continuum varied by more than an order of magnitude on a timescale of weeks. During the large-amplitude flares the centroid energy of the Fe K emission-line complex became significantly redshifted, indicating that the violent activity was occurring close to the putative central black hole where gravitational energy shifts can be sufficiently large. For the continuum, the Compton-y parameter remains roughly constant despite the large-amplitude luminosity variability, with (kT) τ ∼ 20–50.
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Lopez-Pena, Gabriel, Ramon Garcia-Alva, Hugo Laparra-Escareno, Javier E. Anaya-Ayala, Manuel Guerrero-Hernández, and Carlos A. Hinojosa. "Physician-Modified Endovascular Gore Excluder Graft (Handmade Modified) for Complex Abdominal Aortic Aneurysm: A Step-by-Step Approach." Vascular and Endovascular Surgery 54, no. 7 (2020): 656–59. http://dx.doi.org/10.1177/1538574420939741.

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Endovascular repair has become the gold standard for the treatment of infrarenal abdominal aortic aneurysmal disease. Branched and fenestrated commercially custom-made devices have been developed as a treatment option for short necks or juxtarenal aneurysms. However, the lack of availability in some countries and centers, manufacturing time (6-8 weeks requirements), urgent setting in ruptured abdominal aortic aneurysms, and elevated costs make them not a widespread option. Hereby, we expose our step-by-step technique of physician modified Gore Excluder to treat complex aneurysms. Physician-modified endovascular graft (PMEG) has emerged as an alternative to open repair for the treatment of complex aortic aneurysms. The ultimate goal of fenestrations is to increase the proximal sealing zone length. The Gore C3 delivery system allows repositioning of the graft by constraining the proximal part after a back-table physician modification; the PMEG technique with the Gore Excluder C3 delivery system can be used for complex aortic aneurysms repair as an alternative treatment option.
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Cheng, Huajie. "Antimicrobial Resistance Gene Profiles in Communities Selected with Novel and Previously Encountered Antibiotics." Theoretical and Natural Science 89, no. 1 (2025): 78–85. https://doi.org/10.54254/2753-8818/2025.20458.

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Antibiotics are extensively employed worldwide for therapeutic purposes, often leading to overuse, which constitutes a contributing factor to the emergence of antibiotic resistance (ABR). This phenomenon arises from diminished effectiveness of antibiotics in treating bacterial infections due to resistance development. However, limitations in experimental conditions and equipment making it challenging to pinpoint the precise sources of antibiotic resistance, consequently constraining the breadth of research on ABR. Genomic analysis of antibiotic-resistant bacteria assists in unveiling the origins and pathways of resistance dissemination. This study employs Nanopore-based metagenomic sequencing, enabling direct sequencing of microbial DNA within macrogenomic samples, thereby yielding comprehensive sequence data. Coupled with qPCR and 16S rRNA gene datasets, this approach facilitates the exploration of antibiotic resistance gene distribution and prevalence within microbial communities across different environments Focusing on microbial communities within Scottish farmlands, isolated colonies were exposed to antibiotics (sulfamonomethoxine and erythromycin) for several weeks. By comparing them to untreated control group microorganisms, the identification of antibiotic resistance genes (ABRGs), along with their variations in prevalence and abundance, aims to analyse the impact of these two antibiotics on these species.
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Surekh, P., and A. Varadharaj. "Time Optimization Technique Using Reliable Commitment Model." Asian Review of Civil Engineering 6, no. 2 (2017): 23–30. http://dx.doi.org/10.51983/tarce-2017.6.2.2239.

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Construction is a very complex process and nearly every single project is unique. The resulting number of parts, relative lack of standardization, multiple participants and constraining factors make construction projects a difficult endeavour. Adding to this complexity is the high degree of interdependency inherent to the construction process. Complexity can be defined as “something made up of closely connected parts which are difficult to explain or understand, or a number of different parts intricately related”. Due to the inherent complexity, uncertainty, and variability of the construction process, it is important to study the root causes of time buffer used to protect against those challenging characteristics. Reliable Commitment Model, RCM, a new decision-making tool, using statistical models to develop more reliable work plans at the operational level in repetitive projects. RCM increases planning reliability, reduces variability, and promotes a continuous workflow with short waiting times. The main objective is to study the potential improvement on project performance when using RCM to manage WIP buffers at the site or operational level. Worker weeks and process progress are used as the main performance measures in a repetitive building project. RCM analyses the problems of planning process at the operational level shows that one of the most important reason for non-completion of weekly plans in repetitive project is the lack of WIP. RCM predicts the process progress by using variables such as Worker weeks, WIP buffer and planned progress, using Multiple Linear Regression (MLR) at the operational level.
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Greenberg, J. P., A. Guenther, A. Turnipseed, et al. "A tethered-balloon PTRMS sampling approach for rapid surveying of landscape-scale biogenic VOC fluxes." Atmospheric Measurement Techniques Discussions 7, no. 1 (2014): 979–99. http://dx.doi.org/10.5194/amtd-7-979-2014.

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Abstract. To survey landscape-scale fluxes of biogenic gases, a 100 m Teflon tube was attached to a tethered balloon as a sampling inlet for a fast response Proton Transfer Reaction Mass Spectrometer (PTRMS). Along with meteorological instruments deployed on the tethered balloon and at 3 m and outputs from a regional weather model, these observations were used to estimate landscape scale biogenic volatile organic compound fluxes with two micrometeorological techniques: mixed layer variance and surface layer gradients. This highly mobile sampling system was deployed at four field sites near Barcelona to estimate landscape-scale BVOC emission factors in a relatively short period (3 weeks). The two micrometeorological techniques agreed within the uncertainty of the flux measurements at all four sites even though the locations had considerable heterogeneity in species distribution and complex terrain. The observed fluxes were significantly different than emissions predicted with an emission model using site-specific emission factors and land-cover characteristics. Considering the wide range in reported BVOC emission factors of VOCs for individual vegetation species (more than an order of magnitude), this flux estimation technique is useful for constraining BVOC emission factors used as model inputs.
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Gheller, Brandon JF, Phillip Joy, and Daphne Lordly. "A Qualitative Study Exploring the Experience of the Male Dietitian from Student to Professional." Canadian Journal of Dietetic Practice and Research 79, no. 2 (2018): 55–59. http://dx.doi.org/10.3148/cjdpr-2018-003.

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Purpose: In Canada, dietitians serve a sex-diverse population despite the profession being predominately female (&gt;95%). It is unknown why there are so few male dietitians. The objective of the present study was to explore the experience of the male dietitian, as a minority, in female-dominated dietetics.Methods: Two semi-structured interviews were conducted, approximately 6 weeks apart, with Nova Scotian male dietitians. The interviews prompted participants to reflect on their experience of being a male dietitian. Interviews were analyzed using Interpretative Phenomenological Analysis.Results: Male dietitians with between 1 and 17 years of experience participated (n = 6). Participant experiences were expressed as 4 themes: (i) feelings of difference and otherness, (ii) adapting to the female-dominated culture, (iii) constructing a professional identity, and (iv) passion as the driver for success. A theoretical framework for understanding the male dietitian’s experience was outlined.Conclusion: The experience of the male dietitian is unique and is a consequence of training and practicing in a female-dominated space. The effect of adaptation and construction of a professional identity that is a response to female-dominated cultural norms is wide ranging and may be constraining for male practitioners thereby affecting their contributions to the field.
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Istomin, Timofei, Elia Leoni, Davide Molteni, Amy L. Murphy, Gian Pietro Picco, and Maurizio Griva. "Janus." Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies 5, no. 4 (2021): 1–33. http://dx.doi.org/10.1145/3494978.

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Proximity detection is at the core of several mobile and ubiquitous computing applications. These include reactive use cases, e.g., alerting individuals of hazards or interaction opportunities, and others concerned only with logging proximity data, e.g., for offline analysis and modeling. Common approaches rely on Bluetooth Low Energy (BLE) or ultra-wideband (UWB) radios. Nevertheless, these strike opposite tradeoffs between the accuracy of distance estimates quantifying proximity and the energy efficiency affecting system lifetime, effectively forcing a choice between the two and ultimately constraining applicability. Janus reconciles these dimensions in a dual-radio protocol enabling accurate and energy-efficient proximity detection, where the energy-savvy BLE is exploited to discover devices and coordinate their distance measurements, acquired via the energy-hungry UWB. A model supports domain experts in configuring Janus for their use cases with predictable performance. The latency, reliability, and accuracy of Janus are evaluated experimentally, including realistic scenarios endowed with the mm-level ground truth provided by a motion capture system. Energy measurements show that Janus achieves weeks to months of autonomous operation, depending on the use case configuration. Finally, several large-scale campaigns exemplify its practical usefulness in real-world contexts.
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Specht, Joshua. "A Failure to Prohibit: New York City's Underground Bob Veal Trade." Journal of the Gilded Age and Progressive Era 12, no. 4 (2013): 475–501. http://dx.doi.org/10.1017/s1537781413000339.

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During the Progressive Era, bob veal, the meat of calves slaughtered at younger than four weeks of age, was incorrectly believed to be poisonous, and its sale was prohibited in areas across the United States. Yet a thriving underground trade persisted. This article studies bob veal's prohibition in Progressive Era New York City to understand where the meat was coming from, how it reached diners' tables, and who was eating it. I argue that bob veal's consumers, many of whom were recent immigrants and the urban poor, recognized the meat was benign. In examining the prohibition's failure, this article studies the politics of regulation and policing. For the ban's advocates, the language and assumptions of the broader pure food and public health movements were simultaneously empowering and constraining, giving reformers a political language to build institutional support for the prohibition and helping journalists sell newspapers even as this language required effacing the complexity of the bob veal trade. From the perspective of bob veal's many producers, smugglers, and consumers, this article highlights how a diffuse social power—a politics on the ground—can trump formal authority.
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Sims, Richard P., Mohamed M. M. Ahmed, Brian J. Butterworth, et al. "High interannual surface pCO2 variability in the southern Canadian Arctic Archipelago's Kitikmeot Sea." Ocean Science 19, no. 3 (2023): 837–56. http://dx.doi.org/10.5194/os-19-837-2023.

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Abstract. Warming of the Arctic due to climate change means the Arctic Ocean is now free from ice for longer, as sea ice melts earlier and refreezes later. Yet, it remains unclear how this extended ice-free period will impact carbon dioxide (CO2) fluxes due to scarcity of surface ocean CO2 measurements. Baseline measurements are urgently needed to understand spatial and temporal air–sea CO2 flux variability in the changing Arctic Ocean. There is also uncertainty as to whether the previous basin-wide surveys are representative of the many smaller bays and inlets that make up the Canadian Arctic Archipelago (CAA). By using a research vessel that is based in the remote Inuit community of Ikaluqtuutiak (Cambridge Bay, Nunavut), we have been able to reliably survey pCO2 shortly after ice melt and access previously unsampled bays and inlets in the nearby region. Here we present 4 years of consecutive summertime pCO2 measurements collected in the Kitikmeot Sea in the southern CAA. Overall, we found that this region is a sink for atmospheric CO2 in August (average of all calculated fluxes over the four cruises was −4.64 mmol m−2 d−1), but the magnitude of this sink varies substantially between years and locations (average calculated fluxes of +3.58, −2.96, −16.79 and −0.57 mmol m−2 d−1 during the 2016, 2017, 2018 and 2019 cruises, respectively). Surface ocean pCO2 varied by up to 156 µatm between years, highlighting the importance of repeat observations in this region, as this high interannual variability would not have been captured by sparse and infrequent measurements. We find that the surface ocean pCO2 value at the time of ice melt is extremely important in constraining the magnitude of the air–sea CO2 flux throughout the ice-free season. However, further constraining the air–sea CO2 flux in the Kitikmeot Sea will require a better understanding of how pCO2 changes outside of the summer season. Surface ocean pCO2 measurements made in small bays and inlets of the Kitikmeot Sea were ∼ 20–40 µatm lower than in the main channels. Surface ocean pCO2 measurements made close in time to ice breakup (i.e. within 2 weeks) were ∼ 50 µatm lower than measurements made &gt; 4 weeks after breakup. As previous basin-wide surveys of the CAA have focused on the deep shipping channels and rarely measure close to the ice breakup date, we hypothesize that there may be an observational bias in previous studies, leading to an underestimate of the CO2 sink in the CAA. These high-resolution measurements constitute an important new baseline for gaining a better understanding of the role this region plays in the uptake of atmospheric CO2.
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Scandurra, Alessio, Sebastiano Andrea Corinzia, Paolo Caruso, Salvatore Luciano Cosentino, and Giorgio Testa. "Productivity of Wheat Landraces in Rainfed and Irrigated Conditions under Conventional and Organic Input in a Semiarid Mediterranean Environment." Agronomy 14, no. 10 (2024): 2338. http://dx.doi.org/10.3390/agronomy14102338.

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Wheat landraces are locally adapted populations that are suitable for low-input agronomic management and constraining pedo-climatic conditions. The productivity of landraces under high-input and optimal conditions is usually lower than modern wheat varieties. The present study compared the response of Sicilian wheat landraces and modern varieties to organic management, including organic fertilization, and conventional management, including mineral fertilization and chemical weed control, under rainfed condition and supplementary irrigation in a field trial conducted on a xerofluvent soil in a semiarid Mediterranean climate. Modern varieties were on average more productive than landraces, although certain landraces achieved comparable yields, in particular under organic management. The increase in grain yield under conventional management in comparison with the organic management was higher for modern varieties than landraces. The loss of productivity in rainfed conditions was lower for landraces compared to modern varieties. The grain quality traits were similar between landraces and modern varieties and in both cases the conventional management led to an improvement of the traits. These findings highlight the resilience and adaptability of traditional wheat landraces to low-input agricultural systems and offer valuable insights into improving the sustainability and productivity of wheat production in Mediterranean environments.
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Greenberg, J. P., J. Peñuelas, A. Guenther, et al. "A tethered-balloon PTRMS sampling approach for surveying of landscape-scale biogenic VOC fluxes." Atmospheric Measurement Techniques 7, no. 7 (2014): 2263–71. http://dx.doi.org/10.5194/amt-7-2263-2014.

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Abstract. Landscape-scale fluxes of biogenic gases were surveyed by deploying a 100 m Teflon tube attached to a tethered balloon as a sampling inlet for a fast-response proton-transfer-reaction mass spectrometer (PTRMS). Along with meteorological instruments deployed on the tethered balloon and a 3 m tripod and outputs from a regional weather model, these observations were used to estimate landscape-scale biogenic volatile organic compound fluxes with two micrometeorological techniques: mixed layer variance and surface layer gradients. This highly mobile sampling system was deployed at four field sites near Barcelona to estimate landscape-scale biogenic volatile organic compound (BVOC) emission factors in a relatively short period (3 weeks). The two micrometeorological techniques were compared with emissions predicted with a biogenic emission model using site-specific emission factors and land-cover characteristics for all four sites. The methods agreed within the uncertainty of the techniques in most cases, even though the locations had considerable heterogeneity in species distribution and complex terrain. Considering the wide range in reported BVOC emission factors for individual vegetation species (more than an order of magnitude), this temporally short and inexpensive flux estimation technique may be useful for constraining BVOC emission factors used as model inputs.
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Gao, Y., J. C. Cornwell, D. K. Stoecker, and M. S. Owens. "Effects of cyanobacterial-driven pH increases on sediment nutrient fluxes and coupled nitrification-denitrification in a shallow fresh water estuary." Biogeosciences Discussions 9, no. 1 (2012): 1161–98. http://dx.doi.org/10.5194/bgd-9-1161-2012.

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Abstract. Summer cyanobacterial blooms caused an elevation in pH (9 to ~10.5) that lasted for weeks in the shallow and tidal-fresh region of the Sassafras River, a tributary of Chesapeake Bay (USA). Elevated pH promoted desorption of sedimentary inorganic phosphorus and facilitated conversion of ammonium (NH4+) to ammonia (NH3). In this study, we investigated pH effects on exchangeable NH4+ desorption, nutrient pore water diffusion and flux rates of NH4+, soluble reactive phosphorus (SRP), nitrate (NO3–), nitrification, denitrification, and oxygen consumption. pH elevation enhanced the desorption of exchangeable NH4+ because of NH3 formation from both pore water and adsorbed NH4+ pools. Progressive penetration of high pH from the overlying water into sediment promoted the release of SRP and total ammonium (NH4+ and NH3) into pore water. At elevated pH, high sediment-water effluxes of SRP and total ammonium were associated with reduction in nitrification, denitrification and oxygen consumption rates. Alkaline pH and the toxicity of NH3 may inhibit nitrification in the thin aerobic zone, simultaneously constraining coupled nitrification-denitrification with limited NO3– supply and high pH penetration into the anaerobic zone. Geochemical feedbacks to pH elevation, such as enhancement of dissolved nutrient effluxes and reduction in N2 loss via denitrification, may be responsible for the persistence of cyanobacterial blooms in shallow water ecosystems.
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Deshpande, Mugdha, Fakhriddin Pirlepesov, and Thierry Lints. "Rapid encoding of an internal model for imitative learning." Proceedings of the Royal Society B: Biological Sciences 281, no. 1781 (2014): 20132630. http://dx.doi.org/10.1098/rspb.2013.2630.

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As in human infant speech development, vocal imitation in songbirds involves sensory acquisition and memorization of adult-produced vocal signals, followed by a protracted phase of vocal motor practice. The internal model of adult tutor song in the juvenile male brain, termed ‘the template’, is central to the vocal imitation process. However, even the most fundamental aspects of the template, such as when, where and how it is encoded in the brain, remain poorly understood. A major impediment to progress is that current studies of songbird vocal learning use protracted tutoring over days, weeks or months, complicating dissection of the template encoding process. Here, we take the key step of tightly constraining the timing of template acquisition. We show that, in the zebra finch, template encoding can be time locked to, on average, a 2 h period of juvenile life and based on just 75 s of cumulative tutor song exposure. Crucially, we find that vocal changes occurring on the day of training correlate with eventual imitative success. This paradigm will lead to insights on how the template is instantiated in the songbird brain, with general implications for deciphering how internal models are formed to guide learning of complex social behaviours.
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Sandblom, Erik, Albin Gräns, Michael Axelsson, and Henrik Seth. "Temperature acclimation rate of aerobic scope and feeding metabolism in fishes: implications in a thermally extreme future." Proceedings of the Royal Society B: Biological Sciences 281, no. 1794 (2014): 20141490. http://dx.doi.org/10.1098/rspb.2014.1490.

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Temperature acclimation may offset the increased energy expenditure (standard metabolic rate, SMR) and reduced scope for activity (aerobic scope, AS) predicted to occur with local and global warming in fishes and other ectotherms. Yet, the time course and mechanisms of this process is little understood. Acclimation dynamics of SMR, maximum metabolic rate, AS and the specific dynamic action of feeding (SDA) were determined in shorthorn sculpin ( Myoxocephalus scorpius ) after transfer from 10°C to 16°C. SMR increased in the first week by 82% reducing AS to 55% of initial values, while peak postprandial metabolism was initially greater. This meant that the estimated AS during peak SDA approached zero, constraining digestion and leaving little room for additional aerobic processes. After eight weeks at 16°C, SMR was restored, while AS and the estimated AS during peak SDA recovered partly. Collectively, this demonstrated a considerable capacity for metabolic thermal compensation, which should be better incorporated into future models on organismal responses to climate change. A mathematical model based on the empirical data suggested that phenotypes with fast acclimation rates may be favoured by natural selection as the accumulated energetic cost of a slow acclimation rate increases in a warmer future with exacerbated thermal variations.
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26

Gao, Y., J. C. Cornwell, D. K. Stoecker, and M. S. Owens. "Effects of cyanobacterial-driven pH increases on sediment nutrient fluxes and coupled nitrification-denitrification in a shallow fresh water estuary." Biogeosciences 9, no. 7 (2012): 2697–710. http://dx.doi.org/10.5194/bg-9-2697-2012.

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Abstract. Summer cyanobacterial blooms caused an elevation in pH (9 to ~10.5) that lasted for weeks in the shallow and tidal-fresh region of the Sassafras River, a tributary of Chesapeake Bay (USA). Elevated pH promoted desorption of sedimentary inorganic phosphorus and facilitated conversion of ammonium (NH4+) to ammonia (NH3). In this study, we investigated pH effects on exchangeable NH4+ desorption, pore water diffusion and the flux rates of NH4+, soluble reactive phosphorus (SRP) and nitrate (NO3−), nitrification, denitrification, and oxygen consumption. Elevated pH enhanced desorption of exchangeable NH4+ through NH3 formation from both pore water and adsorbed NH4+ pools. Progressive penetration of high pH from the overlying water into sediment promoted the mobility of SRP and the release of total ammonium (NH4+ and NH3) into the pore water. At elevated pH levels, high sediment-water effluxes of SRP and total ammonium were associated with reduction of nitrification, denitrification and oxygen consumption rates. Alkaline pH and the toxicity of NH3 may inhibit nitrification in the thin aerobic zone, simultaneously constraining coupled nitrification–denitrification with limited NO3− supply and high pH penetration into the anaerobic zone. Geochemical feedbacks to pH elevation, such as enhancement of dissolved nutrient effluxes and reduction in N2 loss via denitrification, may enhance the persistence of cyanobacterial blooms in shallow water ecosystems.
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27

Drag, David W., Rebecca Slattery, Matthew Siebers, Evan H. DeLucia, Donald R. Ort, and Carl J. Bernacchi. "Soybean photosynthetic and biomass responses to carbon dioxide concentrations ranging from pre-industrial to the distant future." Journal of Experimental Botany 71, no. 12 (2020): 3690–700. http://dx.doi.org/10.1093/jxb/eraa133.

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Abstract Increasing atmospheric carbon dioxide concentration ([CO2]) directly impacts C3 plant photosynthesis and productivity, and the rate at which [CO2] is increasing is greater than initially predicted by worst-case scenario climate models. Thus, it is increasingly important to assess the physiological responses of C3 plants, especially those that serve as important crops, to [CO2] beyond the mid-range levels used in traditional experiments. Here, we grew the C3 crop soybean (Glycine max) at eight different [CO2] levels spanning subambient (340 ppm) to the highest level thought plausible (~2000 ppm) in chambers for 5 weeks. Physiological development was delayed and plant height and total leaf area increased at [CO2] levels higher than ambient conditions, with very little difference in these parameters among the elevated [CO2] treatments &amp;gt;900 ppm. Daily photosynthesis initially increased with rising [CO2] but began to level off at ~1000 ppm CO2. Similar results occurred in biomass accumulation. Thus, as [CO2] continues to match or exceed the worst-case emission scenarios, these results indicate that carbon gain, growth, and potentially yield increases will diminish, thereby ultimately constraining the positive impact that continuing increases in atmospheric [CO2] could have on crop productivity and global terrestrial carbon sinks.
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Emmans, G. C., W. S. Dingwall, J. FitzSimons, and G. Simm. "The predicted and actual rates of intake of a high quality feed by Suffolk rams from 20-70 kg liveweight." Proceedings of the British Society of Animal Production (1972) 1987 (March 1987): 58. http://dx.doi.org/10.1017/s0308229600034942.

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ARC (1980), in its Chapter 2, gives a method for predicting the rate of feed intake of a sheep of a given weight, W, on a given feed (feed class and energy metabolisability, q). In its Chapter 3 a method is given for predicting the growth rate, GR, of a sheep of a given sex and W from its ME intake. Where GR and W are known the latter procedure can be used to predict the rate at which feed, needs to be eaten, from the ME content and q values of the feed, to support the observed GR. A third method is that of Emmans (1985), which predicts the rate of intake of a non-constraining feed with energy as the first limiting resource by a given animal in a given initial state in a thermally neutral environment; the animal is described by its mature protein weight, Pm kg, its mature lipid:protein ratio, LPRm, its Gompertz rate parameter for protein growth, B/day, and its fattening rate parameter, b, where (b + 1) is the allometric exponent for body lipid on body protein in potential growth.The three methods were used to predict the intakes of Suffolk rams and the predictions compared with the intakes observed in an experiment.The data were from 66 Suffolk rams born in mid-January, weaned at 8 weeks into single pens and given free and continuous access to the feed shown in Table 1. Their intakes and weights were recorded for successive periods of 2, 2, 2, 2, and 3 weeks from 20th March. The sheep were split into three groups on the basis of their weights on 20th March with mean values of 22, 27 and 33 kg. On the basis of their weights the second and third groups were judged to be 9 and 19 days respectively ahead of the first group.
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Atwell, Brian J., Martin L. Henery, Gordon S. Rogers, Saman P. Seneweera, Marie Treadwell, and Jann P. Conroy. "Canopy development and hydraulic function in Eucalyptus tereticornis grown in drought in CO2-enriched atmospheres." Functional Plant Biology 34, no. 12 (2007): 1137. http://dx.doi.org/10.1071/fp06338.

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We report on the relationship between growth, partitioning of shoot biomass and hydraulic development of Eucalyptus tereticornis Sm. grown in glasshouses for six months. Close coordination of stem vascular capacity and shoot architecture is vital for survival of eucalypts, especially as developing trees are increasingly subjected to spasmodic droughts and rising atmospheric CO2 levels. Trees were exposed to constant soil moisture deficits in 45 L pots (30–50% below field capacity), while atmospheric CO2 was raised to 700 μL CO2 L–1 in matched glasshouses using a hierarchical, multi-factorial design. Enrichment with CO2 stimulated shoot growth rates for 12–15 weeks in well-watered trees but after six months of CO2 enrichment, shoot biomasses were not significantly heavier (30% stimulation) in ambient conditions. By contrast, constant drought arrested shoot growth after 20 weeks under ambient conditions, whereas elevated CO2 sustained growth in drought and ultimately doubled the shoot biomass relative to ambient conditions. These growth responses were achieved through an enhancement of lateral branching up to 8-fold due to CO2 enrichment. In spite of larger transpiring canopies, CO2 enrichment also improved the daytime water status of leaves of droughted trees. Stem xylem development was highly regulated, with vessels per unit area and cross sectional area of xylem vessels in stems correlated inversely across all treatments. Furthermore, vessel numbers related to the numbers of leaves on lateral branches, broadly supporting predictions arising from Pipe Model Theory that the area of conducting tissue should correlate with leaf area. Diminished water use of trees in drought coincided with a population of narrower xylem vessels, constraining hydraulic capacity of stems. Commensurate with the positive effects of elevated CO2 on growth, development and leaf water relations of droughted trees, the capacity for long-distance water transport also increased.
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Marchesi, S., X. Zhao, N. Torres-Albà, et al. "Compton-thick AGN in the NuSTAR Era. VIII. A joint NuSTAR–XMM-Newton Monitoring of the Changing-look Compton-thick AGN NGC 1358." Astrophysical Journal 935, no. 2 (2022): 114. http://dx.doi.org/10.3847/1538-4357/ac80be.

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Abstract We present the multi-epoch monitoring with NuSTAR and XMM-Newton of NGC 1358, a nearby Seyfert 2 galaxy whose properties made it a promising candidate X-ray changing-look active galactic nucleus (AGN), i.e., a source whose column density could transition from its 2017 Compton-thick (having LOS hydrogen column density N H,LOS &gt; 1024 cm−2) state to a Compton-thin (N H,LOS &lt; 1024 cm−2) one. The multi-epoch X-ray monitoring confirmed the presence of significant N H,LOS variability over timescales of weeks to years, and allowed us to confirm the changing-look nature of NGC 1358, which has most recently been observed in a Compton-thin status. Multi-epoch monitoring with NuSTAR and XMM-Newton is demonstrated to be highly effective in simultaneously constraining three otherwise highly degenerate parameters: the torus average column density and covering factor, and the inclination angle between the torus axis and the observer. We find a tentative anticorrelation between column density and luminosity, which can be understood under the framework of chaotic cold accretion clouds driving recursive AGN feedback. The monitoring campaign of NGC 1358 has proven the efficiency of our newly developed method to select candidate N H,LOS-variable, heavily obscured AGN, which we plan to soon extend to a larger sample to better characterize the properties of the obscuring material surrounding accreting supermassive black holes, as well as to constrain AGN feeding models.
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Jeon, Ji-Won, Young-Ji Han, Seung-Hwan Cha, et al. "Application of the Passive Sampler Developed for Atmospheric Mercury and Its Limitation." Atmosphere 10, no. 11 (2019): 678. http://dx.doi.org/10.3390/atmos10110678.

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In this study, a passive sampler for gaseous elemental mercury (GEM) was developed and applied to field monitoring. Three Radiello® diffusive bodies with gold-coated beads as Hg adsorbent were installed in an acrylic external shield. Hg uptake mass linearly increased as the deployment time increased until 8 weeks with an average gaseous Hg concentration of 2 ng m−3. The average of the experimental sampling rate (SR) was 0.083 m3 day−1 and showed a good correlation with theoretical SRs, indicating that a major adsorption mechanism was molecular diffusion. Nonetheless, the experimental SR was approximately 33% lower than the modeled SR, which could be associated with inefficient uptake of GEM in the sampler or uncertainty in constraining model parameters. It was shown that the experimental SR was statistically affected by temperature and wind speed but the calibration equation for the SR by meteorological variables should be obtained with a wider range of variables in further investigation. When the uptake rates were compared to the active Hg measurements, the correlation was not significant because the passive sampler was not sufficiently adept at detecting a small difference in the GEM concentration of from 1.8 to 2.0 ng m−3. However, the results for spatial Hg concentrations measured near cement plants in Korea suggest a possible application in field monitoring. Future research is needed to fully employ the developed passive sampler in quantitative assessment of Hg concentrations.
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Yang, Zhou, Wang, et al. "Magnesium Deficiency Induced Global Transcriptome Change in Citrus sinensis Leaves Revealed by RNA-Seq." International Journal of Molecular Sciences 20, no. 13 (2019): 3129. http://dx.doi.org/10.3390/ijms20133129.

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Magnesium (Mg) deficiency is one of the major constraining factors that limit the yield and quality of agricultural products. Uniform seedlings of the Citrus sinensis were irrigated with Mg deficient (0 mM MgSO4) and Mg sufficient (1 mM MgSO4) nutrient solutions for 16 weeks. CO2 assimilation, starch, soluble carbohydrates, TBARS content and H2O2 production were measured. Transcriptomic analysis of C. sinensis leaves was performed by Illumina sequencing. Our results showed that Mg deficiency decreased CO2 assimilation, but increased starch, sucrose, TBARS content and H2O2 production in C. sinensis leaves. A total of 4864 genes showed differential expression in response to Mg deficiency revealed by RNA-Seq and the transcriptomic data were further validated by real-time quantitative PCR (RT-qPCR). Gene ontology (GO) enrichment analysis indicated that the mechanisms underlying Mg deficiency tolerance in C. sinensis may be attributed to the following aspects: a) enhanced microtubule-based movement and cell cycle regulation; b) elevated signal transduction in response to biotic and abiotic stimuli; c) alteration of biological processes by tightly controlling phosphorylation especially protein phosphorylation; d) down-regulation of light harvesting and photosynthesis due to the accumulation of carbohydrates; e) up-regulation of cell wall remodeling and antioxidant system. Our results provide a comprehensive insight into the transcriptomic profile of key components involved in the Mg deficiency tolerance in C. sinensis and enrich our understanding of the molecular mechanisms by which plants adapted to a Mg deficient condition.
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Brimblecombe, Julie, Megan Ferguson, Federica Barzi, Clare Brown, and Kylie Ball. "Mediators and moderators of nutrition intervention effects in remote Indigenous Australia." British Journal of Nutrition 119, no. 12 (2018): 1424–33. http://dx.doi.org/10.1017/s0007114518000880.

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AbstractWe conducted a longitudinal dietary intervention study to assess the impact of a store-based intervention on mediators and moderators and consequent dietary behaviour in Indigenous communities in remote Australia. We assessed dietary intake of fruit, vegetable, water and sweetened soft drink, mediators and moderators among 148, eighty-five and seventy-three adult participants (92 % women) at baseline (T1), end of intervention (T2) and at 24 weeks post intervention (T3), respectively. Mediators included perceived affordability and self-efficacy. Moderators were barriers to eat more fruit and vegetables and food security. Mixed-effects models were used to determine changes in mediators and moderators with time and associations between these and each dietary outcome. Perceived vegetable affordability increased from T1 (19 %; 95 % CI 11, 27) to T2 (38 %; 95 % CI 25, 51) (P=0·004) and returned to baseline levels at T3. High self-efficacy to eat more fruit and vegetables and to drink less soft drink decreased from T1 to T3. A reduction in soft drink intake of 27 % (95 % CI −44, −4; P=0·02) was reported at T3 compared with T1; no changes with time were observed for all other outcome measures. Regardless of time, vegetable intake was positively associated with self-efficacy to cook and try new vegetables, no barriers and food security. The dietary intervention went someway to improving perceived affordability of vegetables but was probably not strong enough to overcome other mediators and moderators constraining behaviour change. Meaningful dietary improvement in this context will be difficult to achieve without addressing underlying constraints to behaviour change.
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Kilgour, Delaney B., Christopher M. Jernigan, Olga Garmash, et al. "Cloud processing of dimethyl sulfide (DMS) oxidation products limits sulfur dioxide (SO2) and carbonyl sulfide (OCS) production in the eastern North Atlantic marine boundary layer." Atmospheric Chemistry and Physics 25, no. 3 (2025): 1931–47. https://doi.org/10.5194/acp-25-1931-2025.

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Abstract. Dimethyl sulfide (DMS) is the major sulfur species emitted from the ocean. The gas-phase oxidation of DMS by hydroxyl radicals proceeds through the stable, soluble intermediate hydroperoxymethyl thioformate (HPMTF), eventually forming carbonyl sulfide (OCS) and sulfur dioxide (SO2). Recent work has shown that HPMTF is efficiently lost to marine boundary layer (MBL) clouds, thus arresting OCS and SO2 production and their contributions to new-particle formation and growth events. To date, no long-term field studies exist to assess the extent to which frequent cloud processing impacts the fate of HPMTF. Here, we present 6 weeks of measurements of the cloud fraction and the marine sulfur species methanethiol, DMS, and HPMTF made at the Atmospheric Radiation Measurement (ARM) research facility on Graciosa Island, Azores, Portugal. Using an observationally constrained chemical box model, we determine that cloud loss is the dominant sink of HPMTF in this region of the MBL during the study, accounting for 79 %–91 % of HPMTF loss on average. When accounting for HPMTF uptake to clouds, we calculate campaign average reductions in DMS-derived MBL SO2 and OCS of 52 %–60 % and 80 %–92 % for the study period. Using yearly measurements of the site- and satellite-measured 3D cloud fraction and DMS climatology, we infer that HPMTF cloud loss is the dominant sink of HPMTF in the eastern North Atlantic during all seasons and occurs on timescales faster than what is prescribed in global chemical transport models. Accurately resolving this rapid loss of HPMTF to clouds has important implications for constraining drivers of MBL new-particle formation.
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Blanton, Sarah, and Steven L. Wolf. "An Application of Upper-Extremity Constraint-Induced Movement Therapy in a Patient With Subacute Stroke." Physical Therapy 79, no. 9 (1999): 847–53. http://dx.doi.org/10.1093/ptj/79.9.847.

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Abstract Background and Purpose. The purpose of this case report is to demonstrate the application of constraint-induced movement therapy with an individual with upper-extremity hemiparesis within 4 months after sustaining a cerebrovascular accident (stroke). Such patients often fail to develop full potential use of their affected upper extremity, perhaps due to a “learned nonuse phenomenon.” Case Description. The patient was a 61-year-old woman with right-sided hemiparesis resulting from an ischemic lacunar infarct in the posterior limb of the left internal capsule. The patient's less-involved hand was constrained in a mitten so that she could not use the hand during waking hours, except for bathing and toileting. On each weekday of the 14-day intervention period, the patient spent 6 hours being supervised while performing tasks using the paretic upper extremity. Pretreatment, posttreatment, and 3-month follow-up outcome measures included the Wolf Motor Function Test and the Motor Activity Log (MAL). Outcomes. For the Wolf Motor FunctionTest, both the mean and median times to complete 16 tasks improved from pretreatment to posttreatment and from posttreatment to follow-up. Results of the MAL indicated an improved self-report of both “how well” and “how much” the patient used her affected limb in 30 specified daily tasks. These improvements persisted to the follow-up. Discussion. Two weeks of constraining the unaffected limb, coupled with practice of functional movements of the impaired limb, may be an effective method for restoring motor function within a few months after cerebral insult. Encouraging improvements such as these strongly suggest the need for a group design that would explore this type of intervention in more detail.
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Mande, Purvi, Keyon Taravati, Michael Rosenblum, and Ann Marshak Rothstein. "Taking a ‘Toll’ on Skin: A novel TLR9-deficient Model of Cutaneous Lupus." Journal of Immunology 198, no. 1_Supplement (2017): 207.2. http://dx.doi.org/10.4049/jimmunol.198.supp.207.2.

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Abstract Endosomal Toll-like receptors (TLRs), TLR7 and TLR9 have been implicated in the pathogenesis of systemic lupus erythematosus (SLE). However, their role in cutaneous lupus (CL) is not well established, in part due to lack of appropriate mouse models for CL. We developed a novel murine model of CL that depends on T cell recognition of an ovalbumin (OVA) peptide on MHC class II+ cells and closely mimics human CL. These mice develop epidermal hyperplasia associated with mononuclear interface dermatitis and IgG deposition at the dermal-epidermal border within 4 weeks of administration of “pseudo-alloantigen” (OVA)-specific DO11 T cells. Importantly, cutaneous disease is entirely dependent on expression of TLR7 and the loss of TLR9. TLR9KO recipients have fewer DO11 Tregs, more germinal center B cells and more plasma cells than TLR9-sufficient recipients. They make autoantibodies specific for Ro52, a common self-reactivity in human CL. Additional clinical manifestations include extensive accumulation of IFNγ-producing DO11 T cells, elevated class II expression by keratinocytes (KC) and epidermal dendritic cells and extensive KC death. Preliminary data point to a mechanistic role of FasL in KC death that presumably drives skin lesions in this model. Intriguingly, radiation chimeras identify a critical role for radio-resistant TLR9KO cells in the development of cutaneous lesions in this model, suggesting a role for KC or Langerhans cell expression of TLR9 in constraining the development of CL. Our model thus provides a novel, rapid and reproducible system for investigating the opposing roles of TLR9 in CL and SLE. Findings from this study will have important applications in designing TLR-targeting molecules as therapeutic agents for CL.
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Li, Guangyu, Jörg Wieder, Julie T. Pasquier, Jan Henneberger, and Zamin A. Kanji. "Predicting atmospheric background number concentration of ice-nucleating particles in the Arctic." Atmospheric Chemistry and Physics 22, no. 21 (2022): 14441–54. http://dx.doi.org/10.5194/acp-22-14441-2022.

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Abstract. Mixed-phase clouds (MPCs) can have a net warming or cooling radiative effect on Earth's climate influenced by the phase and concentration of cloud particles. They have received considerable attention due to high spatial coverage and occurrence frequency in the Arctic. To initiate ice formation in MPCs at temperatures above −38 ∘C, ice-nucleating particles (INPs) are required, which therefore have important implications on the radiative properties of MPCs by altering the ice-to-liquid ratio of hydrometeors. As a result, constraining ambient INP concentrations could promote accurate representation of cloud microphysical processes and reduce the uncertainties in estimating the cloud-phase-related climate feedback in climate models. Currently, INP parameterizations are lacking for remote Arctic environments. Here we present INP number concentrations and their variability measured in Ny-Ålesund (Svalbard) at temperatures between 0 and −30 ∘C. No distinguishable seasonal difference was observed from 12 weeks of field measurements during October and November 2019 and March and April 2020. Compared to existing studies, the absence of a seasonal difference is not surprising, as most seasonal differences are reported for summer versus winter time INP concentrations. In addition, correlating INP concentrations to aerosol physical properties was not successful. Therefore, we propose a lognormal-distribution-based parameterization to predict Arctic INP concentration solely as a function of temperature, specifically for the transition seasons autumn and spring to fill in the data gap in the literature pertaining to these seasons. In practice, the parameterized variables allow for (i) the prediction of the most likely INP concentrations and (ii) the retrieval of the governing distribution of INP concentrations at given temperatures in the Arctic.
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38

Hossain, Fahad, Sujith Konan, Babar Kayani, Christina Kontoghiorghe, Toby Barrack, and Fares Sami Haddad. "Early Clinical and Radiological Outcomes of the Metaphyseally Fixed Totally Stabilized Knee Prosthesis in Primary Total Knee Arthroplasty." Journal of Knee Surgery 33, no. 07 (2019): 678–84. http://dx.doi.org/10.1055/s-0039-1683976.

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AbstractThe use of valgus–varus constrained (VVC) implant designs in primary total knee arthroplasty (TKA) is considered in situations of severe deformities, bone loss, and inadequate soft tissue balance. It is not known whether the use of such prosthesis designs may predispose to reduced function owing to its constraining design. The components are usually implanted with diaphyseal stem extensions to dissipate the increased forces. The totally stabilized (TS) implant is a contemporary VVC design with metaphyseal fixation only. It has a conforming articulation with increased rotational freedom compared with conventional VVC designs. The aim of this study was to assess whether the use of the contemporary TS implant with its metaphyseally fixed components would be associated with inferior outcomes compared with conventional standard primary posterior stabilized (PS) implants. We reviewed 38 consecutive complex primary TKAs performed using the metaphyseally fixed TS implant and 76 matched patients receiving primary PS TKA, at a minimum follow-up of 24 months. The mean follow-up was 61.1 months (24–102). Only patients with osteoarthritis were included. Clinical outcome was assessed using range of motion (ROM) and Oxford knee score (OKS). Radiographic assessment was performed using the femorotibial angle (FTA) at 6 weeks followed by assessment of bone–implant interface lucencies at final follow-up. There were no major early postoperative complications. The mean postoperative ROM in the TS and PS groups were 114.1 and 112.0, respectively. There was no difference in the mean ROM and OKS between the two groups. The mean FTA for patients in both groups was within 3° of the expected. There was no evidence of progressive lucencies or implant migration at final follow-up. The metaphyseally fixed TS knee design achieves comparable short-term functional outcomes when compared with conventional PS designs in primary knee arthroplasty. Long-term follow-up studies are required to assess survivorship.
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Bailey, Stephen J., Lee M. Romer, James Kelly, Daryl P. Wilkerson, Fred J. DiMenna, and Andrew M. Jones. "Inspiratory muscle training enhances pulmonary O2 uptake kinetics and high-intensity exercise tolerance in humans." Journal of Applied Physiology 109, no. 2 (2010): 457–68. http://dx.doi.org/10.1152/japplphysiol.00077.2010.

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Fatigue of the respiratory muscles during intense exercise might compromise leg blood flow, thereby constraining oxygen uptake (V̇o2) and limiting exercise tolerance. We tested the hypothesis that inspiratory muscle training (IMT) would reduce inspiratory muscle fatigue, speed V̇o2 kinetics and enhance exercise tolerance. Sixteen recreationally active subjects (mean ± SD, age 22 ± 4 yr) were randomly assigned to receive 4 wk of either pressure threshold IMT [30 breaths twice daily at ∼50% of maximum inspiratory pressure (MIP)] or sham treatment (60 breaths once daily at ∼15% of MIP). The subjects completed moderate-, severe- and maximal-intensity “step” exercise transitions on a cycle ergometer before (Pre) and after (Post) the 4-wk intervention period for determination of V̇o2 kinetics and exercise tolerance. There were no significant changes in the physiological variables of interest after Sham. After IMT, baseline MIP was significantly increased (Pre vs. Post: 155 ± 22 vs. 181 ± 21 cmH2O; P &lt; 0.001), and the degree of inspiratory muscle fatigue was reduced after severe- and maximal-intensity exercise. During severe exercise, the V̇o2 slow component was reduced (Pre vs. Post: 0.60 ± 0.20 vs. 0.53 ± 0.24 l/min; P &lt; 0.05) and exercise tolerance was enhanced (Pre vs. Post: 765 ± 249 vs. 1,061 ± 304 s; P &lt; 0.01). Similarly, during maximal exercise, the V̇o2 slow component was reduced (Pre vs. Post: 0.28 ± 0.14 vs. 0.18 ± 0.07 l/min; P &lt; 0.05) and exercise tolerance was enhanced (Pre vs. Post: 177 ± 24 vs. 208 ± 37 s; P &lt; 0.01). Four weeks of IMT, which reduced inspiratory muscle fatigue, resulted in a reduced V̇o2 slow-component amplitude and an improved exercise tolerance during severe- and maximal-intensity exercise. The results indicate that the enhanced exercise tolerance observed after IMT might be related, at least in part, to improved V̇o2 dynamics, presumably as a consequence of increased blood flow to the exercising limbs.
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40

Chavan, Nitika S., and Raghumahanti Raghuveer. "Lower limb rehabilitation using modified constraint-induced movement therapy and motor relearning program on balance and gait in sub-acute hemiplegic stroke: a comparative study." F1000Research 12 (September 1, 2023): 1098. http://dx.doi.org/10.12688/f1000research.138127.1.

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Background: A stroke is described by the World Health Organization as “a clinical syndrome with rapidly developing symptoms that consist of a focal (or global, in a situation of coma) disruption of cerebral function that lasts more than 24 hours or leads to mortality without a known cause other than a vascular origin”. Stroke is the most prevalent cause of impairment and mortality on a global scale. Modified constraint-induced movement therapy (mCIMT) is an approach to therapy for motor disabilities that involves constraining the movements of the nonparetic limb, diligent practice and behaviour modification to extend the time the paretic limb is utilized for daily tasks. The motor relearning program (MRP) method involves many aspects of motor learning theory and is helpful in providing instructions for retraining practical skills (including walking, standing and sitting in balance and transferring abilities). So, the objective of this study is to assess the impact of the MRP and mCIMT on balance and gait in sub-acute hemiplegic stroke patients. Methods: In this study, each group will consist of 17 people in total. The randomization procedure will be conducted using a computer-generated random number system. For sample distribution, we will use the sequentially numbered opaque sealed envelope technique. Outcome measures will be as follows: Berg balance scale, Dynamic gait index, Trunk impairment scale, Functional reach test, 10 Meter walk test and Fall efficacy test. Each patient will be evaluated prior to and during treatment at baseline and six weeks later. Conclusions: There is sufficient evidence to derive the conclusion that the functional mobility and balance of stroke victims can be improved with physiotherapy. Therefore, this study will try to seek the comparison of mCIMT and MRP in sub-acute stroke subjects and compare the two regimes to determine which one will be superior. Registration: CTRI (CTRI/2023/05/052674; 16/05/2023).
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Chavan, Nitika S., and Raghumahanti Raghuveer. "Lower limb rehabilitation using modified constraint-induced movement therapy and motor relearning program on balance and gait in sub-acute hemiplegic stroke: a comparative study." F1000Research 12 (March 28, 2024): 1098. http://dx.doi.org/10.12688/f1000research.138127.2.

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Background A stroke is described by the World Health Organization as “a clinical syndrome with rapidly developing symptoms that consist of a focal (or global, in a situation of coma) disruption of cerebral function that lasts more than 24 hours or leads to mortality without a known cause other than a vascular origin”. Stroke is the most prevalent cause of impairment and mortality on a global scale. Modified constraint-induced movement therapy (mCIMT) is an approach to therapy for motor disabilities that involves constraining the movements of the nonparetic limb, diligent practice and behaviour modification to extend the time the paretic limb is utilized for daily tasks. The motor relearning program (MRP) method involves many aspects of motor learning theory and is helpful in providing instructions for retraining practical skills (including walking, standing and sitting in balance and transferring abilities). So, the objective of this study is to assess the impact of the MRP and mCIMT on balance and gait in sub-acute hemiplegic stroke patients. Methods In this study, each group will consist of 17 people in total. The randomization procedure will be conducted using a computer-generated random number system. For sample distribution, we will use the sequentially numbered opaque sealed envelope technique. Outcome measures will be as follows: Berg balance scale, Dynamic gait index, Trunk impairment scale, Functional reach test, 10 Meter walk test and Fall efficacy test. Each patient will be evaluated prior to and during treatment at baseline and six weeks later. Conclusions There is sufficient evidence to derive the conclusion that the functional mobility and balance of stroke victims can be improved with physiotherapy. Therefore, this study will try to seek the comparison of mCIMT (group A) and MRP (group B) in sub-acute stroke subjects and compare the two regimes to determine which one will be superior. Registration CTRI (CTRI/2023/05/052674; 16/05/2023).
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Yang, Yaling, Xiuhua Gao, Xin Han, et al. "Inactivation of INK4a/ARF Accelerates the Development of PTEN Deficient T-ALL." Blood 116, no. 21 (2010): 4197. http://dx.doi.org/10.1182/blood.v116.21.4197.4197.

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Abstract Abstract 4197 Introduction: Acute T-lymphoblastic leukemia/lymphoma (T-ALL) is a group of heterogeneous disease with deregulated expression of variable types of genes. PTEN and INK4a/ARF are among the most frequently inactivated tumor suppressors in human T-ALL. The PTEN gene encodes a phosphatase that negatively regulates the phosphatidylinositol 3-kinase (PI3K) pathway activity. PI3K activates a variety of key signaling proteins that are critical in cell cycle control and cell survival. The Ink4a/Arf gene encodes two distinct tumor suppressors, p16 INK4a and p14 ARF (p19ARF in mice), that function as regulators of the pRB and p53 pathways, respectively. Since dual inactivation of PTEN and INK4a/ARF tumor suppressor genes occurs relatively frequent in human T-ALL, we investigated the specific role and inter-relationship of PTEN and INK4a/ARF tumor suppressor genes in the pathogenesis of T-ALL in genetically engineered mouse models (GEMMs). Methods: We have intercrossed the Ptenflox/flox mice with Ink4a/Arfflox/flox mice, generating compound conditional KO mice carrying both Ptenflox/flox and Ink4a/Arfflox/flox alleles. The compound Ptenflox/flox and Ink4a/Arfflox/flox mice were further intercrossed with Lck-Cre mice, an extensively characterized transgenic mouse strain that expresses Cre recombinase under the T-cell specific LCK promoter. The Lck-Cre transgenic mice express Cre in T-lymphoid cells, including T-lymphoid cells at early developmental stage. Serial analyses from birth to 8 months of age (9 time points) and/or end-point study were performed for a phenotypic workup. Kaplan-Meier curves for overall and tumor-free survival were generated at the end of the study. Grossly normal or tumor-bearing tissue was harvested for histopathlogical and molecular analyses. Results: Molecular analyses showed expected recombinant alleles and absence of Pten and INK4a/ARF proteins in mouse embryonic fibroblasts (MEFs) and T-cells after Cre-mediated excision with concurrent increased expression of phosphorylated Akt indicating the proper deletion of the Pten tumor suppressor gene. Mice with T-cell specific deletion of either Pten, Ink4a/Arf or Pten and Ink4a/Arf were closely monitored closely for perturbations in the hematolymphoid system. The mean disease-free survival (lack of palpable adenopathy) of tInk4a/Arf-/- and tPten-/-, littermates averaged 53, 30 weeks, respectively, while compound and tInk4a/Arf-/- and tPten-/- mice succumbed between 6 and 24 weeks (mean 12 weeks; p&lt;0.001) to a rapidly progressive disease characterized by generalized wasting, mediastinal mass and enlarged lymph nodes. Histologically, the neoplastic cells are immature lymphoid cells, involving multiple organs and circulating blood. Immunophenotypic studies by flow cytometry demonstrated immature T-cell lineage cells (T-ALL). Conclusions: Using our genetically engineered mouse models, we have provided genetic evidence that INK4a/ARF and PTEN cooperate in constraining the development of T-ALL. These mouse models provide a platform for discovering new molecular targets for T-ALL therapy preclinically. Ongoing efforts focus on further charactering the difference in pathology, the PI3K/AKT pathways, DNA damage, cell cycle control, and drug sensitivities among the various T-ALL models. Disclosures: No relevant conflicts of interest to declare.
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Forkert, Randolf, Yon Ko, Thomas Neuhaus, et al. "G-CSF Induced Expansion and Mobilization of Hematopoietic Stem Cells Is Altered by the Matrix Protein Osteopontin." Blood 108, no. 11 (2006): 1400. http://dx.doi.org/10.1182/blood.v108.11.1400.1400.

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Abstract Stem cells reside in a physical microenvironment or niche where a balance of signals controls their proliferation, differentiation and death. Components of the specialized microenvironment have generally been defined in terms of cells and signaling pathways affecting stem cell maintenance or expansion. We have defined a role for a matrix glycoprotein that provides a constraining function on hematopoietic stem cells within the bone marrow microenvironment. Osteopontin (OPN) is an abundant glycoprotein in bone that modifies primitive hematopoietic cell number and function in a stem cell non-autonomous manner. Here we analyzed the role of OPN for regulating stem cell mobilization and pool size in times of G-CSF induced marrow stress, a context close to the clinical setting of stem cell mobilization not well understood so far. Bone marrow stromal cells show an enhanced expression of OPN under stimulation with G-CSF, which prompted us to analyze the role of OPN in G-CSF mediated activation of the stem cell niche. First we treated OPN deficient mice and their wild-type littermates with G-CSF for 5 days. We could observe a significant increased stem cell fraction in the peripheral blood and in the bone marrow in the absence of OPN in comparison to the wild-type controls. To evaluate, if this effect is stroma dependent, we first transplanted wild-type bone marrow into wild-type or OPN-deficient recipients. 6 weeks after transplantation we treated these mice with G-CSF for 5 days and analyzed the peripheral blood and the bone marrow for the contents of primitive hematopoietic cells. Here we could detect a significantly increased stem cell fraction in peripheral blood and bone marrow of the OPN−/− recipients in comparison to wild type controls detected by FACS and functional in vitro stem cell assays. We then transplanted the stressed bone marrow in a competitive repopulation assay into wild-type recipients and observed a significant increase of CD45.2 cells from OPN−/− recipient mice up to 12 weeks after transplantation in comparison to wild-type controls, demonstrating an enhanced G-CSF induced expansion of hematopioetic stem cells in the OPN-deficient stem cell niche. Furthermore, we could observe an enhanced expression of Angiopoietin and N-Cadherin in OPN-deficient bone marrow stromal cells after stimulation with G-CSF in comparison to wild-type controls, supporting the stroma dependent expansion of stem cells in the absence of OPN in the G-CSF stimulated stem cell niche. Therefore, OPN is a restricting element of the stem cell niche limiting the size of the stem cell pool and may provide a dynamic mechanism by which excess stem cell expansion is prevented during times of niche stimulation. These findings may provide new insight into expansion and mobilization of hematopoietic stem cells by G-CSF mediated by components of the stem cell niche.
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Kirkegaard, J. A., J. R. Hunt, T. M. McBeath, et al. "Improving water productivity in the Australian Grains industry—a nationally coordinated approach." Crop and Pasture Science 65, no. 7 (2014): 583. http://dx.doi.org/10.1071/cp14019.

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Improving the water-limited yield of dryland crops and farming systems has been an underpinning objective of research within the Australian grains industry since the concept was defined in the 1970s. Recent slowing in productivity growth has stimulated a search for new sources of improvement, but few previous research investments have been targeted on a national scale. In 2008, the Australian grains industry established the 5-year, AU$17.6 million, Water Use Efficiency (WUE) Initiative, which challenged growers and researchers to lift WUE of grain-based production systems by 10%. Sixteen regional grower research teams distributed across southern Australia (300–700 mm annual rainfall) proposed a range of agronomic management strategies to improve water-limited productivity. A coordinating project involving a team of agronomists, plant physiologists, soil scientists and system modellers was funded to provide consistent understanding and benchmarking of water-limited yield, experimental advice and assistance, integrating system science and modelling, and to play an integration and communication role. The 16 diverse regional project activities were organised into four themes related to the type of innovation pursued (integrating break-crops, managing summer fallows, managing in-season water-use, managing variable and constraining soils), and the important interactions between these at the farm-scale were explored and emphasised. At annual meetings, the teams compared the impacts of various management strategies across different regions, and the interactions from management combinations. Simulation studies provided predictions of both a priori outcomes that were tested experimentally and extrapolation of results across sites, seasons and up to the whole-farm scale. We demonstrated experimentally that potential exists to improve water productivity at paddock scale by levels well above the 10% target by better summer weed control (37–140%), inclusion of break crops (16–83%), earlier sowing of appropriate varieties (21–33%) and matching N supply to soil type (91% on deep sands). Capturing synergies from combinations of pre- and in-crop management could increase wheat yield at farm scale by 11–47%, and significant on-farm validation and adoption of some innovations has occurred during the Initiative. An ex post economic analysis of the Initiative estimated a benefit : cost ratio of 3.7 : 1, and an internal return on investment of 18.5%. We briefly review the structure and operation of the initiative and summarise some of the key strategies that emerged to improve WUE at paddock and farm-scale.
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45

Brinkerink, Christiaan D., Cornelia Müller, Heino D. Falcke, et al. "Micro-arcsecond structure of Sagittarius A∗ revealed by high-sensitivity 86 GHz VLBI observations." Astronomy & Astrophysics 621 (January 2019): A119. http://dx.doi.org/10.1051/0004-6361/201834148.

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Context. The compact radio source Sagittarius A∗ (Sgr A∗) in the Galactic centre is the primary supermassive black hole candidate. General relativistic magnetohydrodynamical (GRMHD) simulations of the accretion flow around Sgr A∗ predict the presence of sub-structure at observing wavelengths of ∼3 mm and below (frequencies of 86 GHz and above). For very long baseline interferometry (VLBI) observations of Sgr A∗ at this frequency the blurring effect of interstellar scattering becomes sub-dominant, and arrays such as the high sensitivity array (HSA) and the global mm-VLBI array (GMVA) are now capable of resolving potential sub-structure in the source. Such investigations help to improve our understanding of the emission geometry of the mm-wave emission of Sgr A∗, which is crucial for constraining theoretical models and for providing a background to interpret 1 mm VLBI data from the Event Horizon Telescope (EHT). Aims. Following the closure phase analysis in our first paper, which indicates asymmetry in the 3 mm emission of Sgr A∗, here we have used the full visibility information to check for possible sub-structure. We extracted source size information from closure amplitude analysis, and investigate how this constrains a combined fit of the size-frequency relation and the scattering law for Sgr A∗. Methods. We performed high-sensitivity VLBI observations of Sgr A∗ at 3 mm using the Very Long Baseline Array (VLBA) and the Large Millimeter Telescope (LMT) in Mexico on two consecutive days in May 2015, with the second epoch including the Greenbank Telescope (GBT). Results. We confirm the asymmetry for the experiment including GBT. Modelling the emission with an elliptical Gaussian results in significant residual flux of ∼10 mJy in south-eastern direction. The analysis of closure amplitudes allows us to precisely constrain the major and minor axis size of the main emission component. We discuss systematic effects which need to be taken into account. We consider our results in the context of the existing body of size measurements over a range of observing frequencies and investigate how well-constrained the size-frequency relation is by performing a simultaneous fit to the scattering law and the size-frequency relation. Conclusions. We find an overall source geometry that matches previous findings very closely, showing a deviation in fitted model parameters less than 3% over a time scale of weeks and suggesting a highly stable global source geometry over time. The reported sub-structure in the 3 mm emission of Sgr A∗ is consistent with theoretical expectations of refractive noise on long baselines. However, comparing our findings with recent results from 1 mm and 7 mm VLBI observations, which also show evidence for east-west asymmetry, we cannot exclude an intrinsic origin. Confirmation of persistent intrinsic substructure will require further VLBI observations spread out over multiple epochs.
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Sharma, D. L., and W. K. Anderson. "Small grain screenings in wheat: interactions of cultivars with season, site, and management practices." Australian Journal of Agricultural Research 55, no. 7 (2004): 797. http://dx.doi.org/10.1071/ar03265.

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Small grains that pass through a 2-mm slotted screen (sievings or screenings) are one of the most important causes of price dockages of wheat in Australia because grain size variation greatly affects flour yield and commercial value. The aims of this study were to examine the effects of season, time of sowing, plant population, and applied nitrogen, and their interactions with cultivars, on small grain screenings. Twenty-one field experiments involving 16 new cultivars and elite crossbreds, and various management variables, were conducted in the medium (annual rainfall 325–450 mm) and low (annual rainfall &lt;325 mm) rainfall zones of the Northern Agricultural Region of Western Australia over 3 diverse cropping seasons (1999–2001). Rainfall events towards the end of the season were critical to the level of screenings. Screenings were higher in season 2000 with terminal drought stress, but were low in 2001 despite severe drought stress during early growth. Delayed seeding caused higher screenings in 1999 (average rainfall with even distribution) and in 2000 (terminal drought) but not consistently in 2001 when early drought stress restricted tillering and spike size thereby constraining the yield level. Strong varietal and time of sowing interactions were evident but the relationship between maturity group and the level of screenings was not consistent. Rather, the ability of cultivars to adjust yield components was more important; 82% of the total variance in small grain screenings was accounted for by a regression model based on variety-specific kernel weight, post-heading rainfall (from about 2 weeks before anthesis), and location factors. The effect of increasing plant population on screenings was mostly negative, with some minor exceptions for a few cultivars in the low-rainfall zone. As applied nitrogen was increased, screenings generally increased and cultivar influenced this trend more than rainfall zone. It is postulated that for a cultivar to be unaffected by applied nitrogen, it should have inherently higher grain weight as well as high stability of grain weight across nitrogen levels. Applied nitrogen had a significant effect on screenings only at higher plant populations. In experiments where the level of screenings exceeded 5%, the yield components that were significantly associated with screenings, in order of relative importance, were grain weight &gt; grain number/area &gt; grain number/head &gt; grain yield. Cultivars differed in production of screenings in response to plant population, nitrogen fertiliser and sowing time. Harrismith was the most sensitive cultivar and Wyalkatchem was overall the most tolerant cultivar. Delayed seeding had the least effect on the screenings of cultivars Westonia, Carnamah, and Wyalkatchem. Carnamah was the most stable cultivar against higher levels of applied nitrogen, whereas Westonia required high plant numbers to contain screenings. It is concluded that cultivars can be classified according to specific sensitivities, and appropriate management practices may be suggested to growers.
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Dubovik, O., T. Lapyonok, Y. J. Kaufman, M. Chin, P. Ginoux, and A. Sinyuk. "Retrieving global sources of aerosols from MODIS observations by inverting GOCART model." Atmospheric Chemistry and Physics Discussions 7, no. 2 (2007): 3629–718. http://dx.doi.org/10.5194/acpd-7-3629-2007.

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Abstract. Knowledge of the global distribution of tropospheric aerosols is important for studying the effects of aerosols on global climate. Chemical transport models rely on archived meteorological fields, accounting for aerosol sources, transport and removal processes can simulate the global distribution of atmospheric aerosols. However, the accuracy of global aerosol modeling is limited. Uncertainty in location and strength of aerosol emission sources is a major factor in limiting modeling accuracy. This paper describes an effort to develop an algorithm for retrieving global sources of aerosol from satellite observations by inverting the GOCART aerosol transport model. To optimize inversion algorithm performance, the inversion was formulated as a generalized multi-term least-squares-type fitting. This concept uses the principles of statistical optimization and unites diverse retrieval techniques into a single flexible inversion procedure. It is particularly useful for choosing and refining a priori constraints in the retrieval algorithm. For example, it is demonstrated that a priori limitations on the partial derivatives of retrieved characteristics, which are widely used in atmospheric remote sensing, can also be useful in inverse modeling for constraining time and space variability of the retrieved global aerosol emissions. The similarities and differences with the standard "Kalman filter" inverse modeling approach and the "Phillips-Tikhonov-Twomey" constrained inversion widely used in remote sensing are discussed. In order to retain the originally high space and time resolution of the global model in the inversion of a long record of observations, the algorithm was expressed using adjoint operators in a form convenient for practical development of the inversion from codes implementing forward model simulations. The inversion algorithm was implemented using the GOCART aerosol transport model. The numerical tests we conducted showed successful retrievals of global aerosol emissions with a 2°×2.5° resolution by inverting the GOCART output. For achieving satisfactory retrieval from satellite sensors such as MODIS, the emissions were assumed constant within the 24 h diurnal cycle and aerosol differences in chemical composition were neglected. Such additional assumptions were needed to constrain the inversion due to limitations of satellite temporal coverage and sensitivity to aerosol parameters. As a result, the algorithm was defined for the retrieval of emission sources of fine and coarse mode aerosols from the MODIS fine and coarse mode aerosol optical thickness data respectively. Numerical tests showed that such assumptions are justifiable, taking into account the accuracy of the model and observations and that it provides valuable retrievals of the location and the strength of the aerosol emissions. The algorithm was applied to MODIS observations during two weeks in August 2000. The global placement of fine mode aerosol sources retrieved from inverting MODIS observations was coherent with available independent knowledge. This was particularly encouraging since the inverse method did not use any a priori information about the sources and it was initialized under a "zero aerosol emission" assumption. The retrieval reproduced the instantaneous global MODIS observations with a standard deviation in fitting of aerosol optical thickness of ~0.04. The optical thickness during high aerosol loading events was reproduced with a standard deviation of ~48%. Applications of the algorithm for the retrieval of coarse mode aerosol emissions were less successful, mainly due to the currently existing lack of MODIS data over high reflectance desert dust sources. Possibilities for enhancing the global satellite data inversion by using diverse a priori constraints on the retrieval are demonstrated. The potential and limitations of applying our approach for the retrieval of global aerosol sources from aerosol remote sensing are discussed.
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Di Giandomenico, Silvana, Ghaith Abu Zeinah, Pouneh Kermani та ін. "Low-Dose Epo after Tgfβ Blockade Triggers Robust Erythropoiesis and Increased RBC Production". Blood 134, Supplement_1 (2019): 2217. http://dx.doi.org/10.1182/blood-2019-129044.

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Background: Therapy for chronic anemias is limited to RBC transfusions and Erythropoiesis Stimulating Agents (ESA) which often work on only transiently or not at all. New approaches to treat chronic anemia are needed but development has been limited by our incomplete understanding of erythropoiesis, most of which relates to the terminal maturation of erythroid precursors. Erythropoietin (Epo) acts during a very narrow window of erythropoiesis, well after progenitor commitment to an exclusively erythroid fate. It is not known if the final steps of RBC maturation are coupled to the earlier stages of hematopoietic stem and progenitor cell (HSPC) differentiation; a process that begins almost three weeks earlier when an HSC starts its march towards committed RBC precursors via a series of branching cell fate decisions.We searched for independent control and compartmentalization of erythropoiesis that could couple early hematopoiesis to terminal erythroid commitment and maturation. Results: We deleted TGFβ1 in megakaryocytes (TGFβ1ΔMk/ΔMk) and found that peripheral blood counts were normal in TGFβ1ΔMk/ΔMkmice compared to TGFβ1FL/FLcontrols despite the pool of primitive hematopoietic cells being expanded (Fig. 1a). Similarly total bone marrow cellularity was normal in TGFβ1ΔMk/ΔMkmice (Fig. 1b). Excess HSCs in TGFβ1ΔMk/ΔMkmice appeared capable of robust differentiation because the number of immature lineage-negative (Linneg) hematopoietic progenitor cells was increased in the marrows of TGFβ1ΔMk/ΔMkmice (Fig. 1c). Thus, it remained unexplained why the expanded number of HSPCs (Fig. 1d) do not increase blood counts and marrow cellularity. We hypothesized that the excess progenitors observed in the TGFβ1ΔMk/ΔMkmice failed to increase blood counts because their progeny were unneeded, and inadequately supported by homeostatic levels of late-acting cytokines. Indeed, bone marrow apoptosis was increased in the TGFβ1ΔMk/ΔMkmice compared to controls, as reported by AnnexinV (AV) binding (Fig. 1e-f). Apoptosis of lineage-marker negative (Linneg), Kit+Sca1neg(LKSneg) HPCs and LKS+HSPCs was rare in both TGFβ1ΔMk/ΔMkmice and littermate controls (Fig. 1g). These results suggest that excess, hematopoietic precursors present in the TGFβ1ΔMk/ΔMkmice are pruned by apoptosis during hematopoietic differentiation. We found 10-fold apoptosis in TGFβ1ΔMk/ΔMkprecursors populations BM (Fig. 1h). Epo levels were normal in the serum of these mice, we reasoned that the excess, unneeded cells were not supported physiologic Epo levels. To test this, we treated mice with exogenous Epo. Indeed, we found that the excess erythroid apoptosis could be rescued by administration of very low doses of Epo (300U/kg)(Fig. 1i-j). Whereas TGFβ1Flox/Floxmice showed minimal reticulocytosis and no change in blood counts, TGFβ1ΔMk/ΔMkmice responded with reticulocytosis and erythrocytosis within 6 days (Fig. 1k-l). In contrast, treatment of mice with TGFβ1 worsened the erythroid apoptosis observed in TGFβ1ΔMk/ΔMkmice and caused mild anemia. These results suggest that erythropoiesis is subject to modular regulation with megakaryocytic TGFβ1 constraining the pool of erythroid committed progenitors that are then licensed to mature via Epo signaling. We thought that blockade of TGFβ signaling could phenocopy these effects by inducing overproduction of erythroid committed precursors. To test this, we pre-treated B6 mice with a TGFβ1 neutralizing antibody (1D11) or non-targeting, isotype control antibody (13C4) and then either PBS or low-dose Epo (Fig. 1m). TGFβ neutralization by 1D11 reduced pSmad2/3 MFI in HSPCs in wild-type mice whereas the 13C4 control had no effect, demonstrating on-target activity (Fig. 1n). Low-dose Epo triggered a brisk erythropoietic response in mice treated with 1D11 but not those treated with the 13C4 control (Fig. 1o). Exogenous Epo rescued the erythroid precursor dropout observed in B6 mice treated with 1D11 but did not affect the low apoptosis observed in mice treated with the 13C4 control (Fig. 1p-r). Therefore, the boundary of megakaryocytic TGFβ1 activity is compartmentalized within the marrow with predominant effects on immature HSPCs while excluding their progeny (Fig. 4s). Conclusion: This work also promises new therapies for chronic anemias by combining TGFβ inhibitors to increase the outflow of immature progenitors with ESAs to support erythroid maturation. Disclosures No relevant conflicts of interest to declare.
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Rogers, Kerry A., Lai Wei, Seema A. Bhat, et al. "A Multicenter Study of Ibrutinib Resistance Development and Intervention with Venetoclax in Patients with Chronic Lymphocytic Leukemia." Blood 134, Supplement_1 (2019): 3049. http://dx.doi.org/10.1182/blood-2019-125360.

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Background: Ibrutinib (ibr) for the treatment of chronic lymphocytic leukemia (CLL) has improved progression-free survival (PFS) compared to other treatments, especially in high-risk patients (pts). However, resistance occurs and is associated with mutations in the drug binding target (BTK) and its immediate downstream target (PLCg2). These ibr resistance mutations (IRmut) are detectable months prior to developing progressive disease (PD) and predict clinical relapse. Prospectively determining the time from starting ibr to development of IRmut and from IRmut detection to PD will improve our understanding of how to manage these patients. Venetoclax (ven) is highly effective after ibr and decreases IRmut. Adding ven to ibr for ibr resistance is a rational choice as this combination is safe and effective in CLL. Adding an agent rather than stopping ibr avoids disease flare associated with ibr discontinuation. This phase 2 study was designed to follow CLL pts taking ibr and at high risk for resistance (observation cohort) and to test ven in combination with ibr for those who develop PD (intervention cohort). This will determine: the incidence of IRmut and PD in this population, the ORR with ibr/ven, and the ability of this combination to eliminate IRmut. Trial Design and Methods: This multisite study will open at 4 centers initially. Eligible pts are adults with CLL taking ibr for ≥12 months and at high risk for ibr resistance defined as having ≥2 prior treatments and del(17p)(p13.1) on FISH panel and/or a complex karyotype. Pts with known IRmut or who cannot continue ibr for any reason are excluded. Enrolled pts enter the observation cohort and are followed every 3 months with a clinic visit, blood counts, and testing for IRmut. Pts who develop IRmut will also have CT scans at their visits to detect PD. Those with IRmut who develop PD by iwCLL 2018 criteria will enter the intervention cohort. Pts in the intervention cohort will start ven in addition to ibr. Ven will be ramped-up over 5 weeks to a target dose of 400mg. Pts will take combination ibr/ven for 12 cycles of 28 days in length. After 12 cycles they will undergo response assessment and those achieving a complete remission (CR) with no detectable leukemia (uMRD) in both the blood and bone marrow will stop ven and continue ibr alone. Those who do not achieve CR with uMRD will continue ibr/ven until cycle 24 and undergo a second response assessment. If in a CR with uMRD after 24 cycles they continue on ibr alone. If a CR with uMRD is not achieved after 24 cycles patients continue ibr/ven until PD, intolerance, death, or end of study which is 30 months after the last patient enters the intervention cohort (Figure). In the intervention cohort all pts will be tested for IRmut in the blood every 3 months with bone marrow testing at response assessments. The study has co-primary endpoints of ORR to combination ibr/ven after 12 cycles and the rate of IRmut negative status at that time in the intervention cohort. ORR will be tested first using a single-stage phase 2 design with a null hypothesis that the rate is ≤50% versus the alternative hypothesis that it is ≥75%. Only if the combination is effective in ORR will the rate of IRmut negative status be formally tested. Constraining overall Type I and II errors to 0.10 using this sequential testing strategy, 26 evaluable pts are required and 28 will be accrued. Secondary endpoints for the intervention cohort are the PFS and overall survival since starting the combination ibr/ven and the incidence and type of adverse events with ibr/ven. Secondary endpoints in the observation cohort are the incidence of IRmut during ibr treatment and the PFS after developing an IRmut. We estimate that 180 pt-years of follow up for the observation cohort will be needed. The yearly rate of mutation development in this population is approximately 20%, therefore this will identify 36 pts with IRmut. Of those with IRmut, approximately 80% will remain eligible to enter the intervention cohort. Accrual to the observation cohort will stop once 28 pts enter the intervention cohort. Conclusion: This multicenter phase 2 trial examines the development of IRmut and clinical resistance to ibr in a cohort of high-risk CLL pts and will determine the efficacy of adding ven to ibr in those who develop PD. We expect to determine the natural course of molecular and clinical ibr resistance in CLL and if adding ven is an effective treatment strategy. Figure Disclosures Rogers: Acerta: Consultancy; Genentech: Research Funding; Abbvie: Research Funding; Janssen: Research Funding. Bhat:Pharmacyclics: Consultancy; Janssen: Consultancy. Stephens:Karyopharm: Research Funding; Gilead: Research Funding; Acerta: Research Funding. Ye:Janssen: Research Funding; Karyopharm: Research Funding; Portola: Research Funding; MingSight: Research Funding; Sanofi: Research Funding. Byrd:Pharmacyclics LLC, an AbbVie Company: Other: Travel Expenses, Research Funding, Speakers Bureau; Janssen: Consultancy, Other: Travel Expenses, Research Funding, Speakers Bureau; Pharmacyclics LLC, an AbbVie Company: Other: Travel Expenses, Research Funding, Speakers Bureau; Acerta: Research Funding; Genentech: Research Funding; Gilead: Other: Travel Expenses, Research Funding, Speakers Bureau; Ohio State University: Patents &amp; Royalties: OSU-2S; Novartis: Other: Travel Expenses, Speakers Bureau; Janssen: Consultancy, Other: Travel Expenses, Research Funding, Speakers Bureau; Gilead: Other: Travel Expenses, Research Funding, Speakers Bureau; Novartis: Other: Travel Expenses, Speakers Bureau; BeiGene: Research Funding; BeiGene: Research Funding; TG Therapeutics: Other: Travel Expenses, Research Funding, Speakers Bureau; Genentech: Research Funding; Ohio State University: Patents &amp; Royalties: OSU-2S; TG Therapeutics: Other: Travel Expenses, Research Funding, Speakers Bureau; Acerta: Research Funding. Woyach:Janssen: Consultancy, Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding; AbbVie: Research Funding; Karyopharm: Research Funding; Loxo: Research Funding; Morphosys: Research Funding; Verastem: Research Funding. OffLabel Disclosure: This abstract discussion the use of combination ibrutinib and venetoclax in CLL.
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Carzon, James, Bruno Abreu, Leighton Regayre, et al. "Statistical constraints on climate model parameters using a scalable cloud-based inference framework." Environmental Data Science 2 (2023). http://dx.doi.org/10.1017/eds.2023.12.

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Abstract Atmospheric aerosols influence the Earth’s climate, primarily by affecting cloud formation and scattering visible radiation. However, aerosol-related physical processes in climate simulations are highly uncertain. Constraining these processes could help improve model-based climate predictions. We propose a scalable statistical framework for constraining the parameters of expensive climate models by comparing model outputs with observations. Using the C3.AI Suite, a cloud computing platform, we use a perturbed parameter ensemble of the UKESM1 climate model to efficiently train a surrogate model. A method for estimating a data-driven model discrepancy term is described. The strict bounds method is applied to quantify parametric uncertainty in a principled way. We demonstrate the scalability of this framework with 2 weeks’ worth of simulated aerosol optical depth data over the South Atlantic and Central African region, written from the model every 3 hr and matched in time to twice-daily MODIS satellite observations. When constraining the model using real satellite observations, we establish constraints on combinations of two model parameters using much higher time-resolution outputs from the climate model than previous studies. This result suggests that within the limits imposed by an imperfect climate model, potentially very powerful constraints may be achieved when our framework is scaled to the analysis of more observations and for longer time periods.
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