410 research outputs found

    Selective removal of phosphorus from high carbon ferromanganese - an improved process

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    The presence of phosphorus is known to deteriorate the mechanical properties of cast steel and other metallic products. Ferromanganese, used as the last additive during steel making, is one of the main sources of phosphorus contamination. Therefore phosphorus has to be removed from the ferromanganese before it is used as a deoxidizing and alloying agent. The bulk of high carbon ferromanganese produced in India continues to have more than 0.35% phosphorus since they are produced by carbothermic reduction process. A systematic study by NML showed that it was possible to remove phosphorus from high carbon liquid ferromanganese successfully from 0.56% to 0.18% using BaCO3 based fluxes at the rate of 16-wt% of the ferromanganese charged. However, the Mn loss varied in the range of 2-5%. The objective of the present study was to optimize the flux consumption as well as minimize the Mn loss with effective dephosphorization by using BaO based calcined pellets instead of BaCO3 based powders. It is easier to handle pellets under plant conditions and eliminate the loss of flux as a dust, which occurs when powder is added. These pellets can be forced towards the bottom of the melt for better efficiency. Another advantage of using pellets is that it utilizes manganese ore fines, which is a waste material in the ferromanganese industry. The results have shown that the addition of moderate amount of MnO into the pellets reduces the Mn loss while it helps dephosphorization. The results achieved indicate that it is possible to achieve more than 60% phosphorus removal using flux addition at 5% by weight of the ferromanganese charged

    Agro-morphological Diversity of High Altitude Bean Landraces in the Kailash Sacred Landscape of Nepal

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    Many varieties of bean are widely grown across diverse agro-ecological zones in Nepal. And opportunities exist for improving the crops and enhancing their resilience to various biotic and abiotic stressors. In this context, an experiment was conducted from June to October 2016 in Khar VDC of Darchula district to study the phenotypic traits of nine landraces of bean (Phaseolus vulgaris L.). The bean landraces were planted using randomized complete block design in three sites (Dhamidera, Dallekh and Sundamunda villages), with three replications in each site for their comparative analysis. The study considered the following phenotypic traits: days to emergence, days to 50% flowering, days to 90% pod maturity, number of nodes, pod length, pod width, number of pods, number of seeds per pod and weight and grain yield for 100 seeds. Kruskal-Wallis test showed significant differences in the landraces both within and among locations. KA-17-08-FB and KA-17-04-FB were late  flowering (63 and 65 days respectively) compared to other landraces whereas KA-17-07-FB flowered earliest (within 42 days). In all three sites, three landraces namely KA-17-07-FB, KA-17-04-FB and KA-17-06-FB were found to be relatively more resistant to pest and diseases than other landraces. Eight out of nine landraces in Dhamidera and Dallekh villages and seven out of nine in Sundamunda village produced seeds greater than 1.0 t/ha. Among the nine varieties KA-17-02-FB was the highest yielding variety, with an average yield of 3.8 t/ha. This study is useful for identifying suitable landraces for future promotion based on their maturity, grain yield, diseases resistance and other qualitative and quantitative characteristics

    Evaluation of chemiluminescence, toluidine blue and histopathology for detection of high risk oral precancerous lesions: A cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>Early detection holds the key to an effective control of cancers in general and of oral cancers in particular. However, screening procedures for oral cancer are not straightforward due to procedural requirements as well as feasibility issues, especially in resource-limited countries.</p> <p>Methods</p> <p>We conducted a cross-sectional study to compare the performance of chemiluminescence, toluidine blue and histopathology for detection of high-risk precancerous oral lesions. We evaluated 99 lesions from 55 patients who underwent chemiluminescence and toluidine blue tests along with biopsy and histopathological examination. We studied inter-as well as intra-rater agreement in the histopathological evaluation and then using latent class modeling, we estimated the operating characteristics of these tests in the absence of a reference standard test.</p> <p>Results</p> <p>There was a weak inter-rater agreement (kappa < 0.15) as well as a weak intra-rater reproducibility (Pearson's r = 0.28, intra-class correlation rho = 0.03) in the histopathological evaluation of potentially high-risk precancerous lesions. When compared to histopathology, chemiluminescence and toluidine blue retention had a sensitivity of 1.00 and 0.59, respectively and a specificity of 0.01 and 0.79, respectively. However, latent class analysis indicated a low sensitivity (0.37) and high specificity (0.90) of histopathological evaluation. Toluidine blue had a near perfect high sensitivity and specificity for detection of high-risk lesions.</p> <p>Conclusion</p> <p>In our study, there was variability in the histopathological evaluation of oral precancerous lesions. Our results indicate that toluidine blue retention test may be better suited than chemiluminescence to detect high-risk oral precancerous lesions in a high-prevalence and low-resource setting like India.</p

    Status, challenges and pathways to the sustainable use of wild species

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    DATA AVAILABILITY : Data will be made available on request.The use of wild species is extensive in both high- and low-income countries. At least 50,000 wild species are used by billions of people around the world for food, energy, medicine, material, education or recreation, contributing significantly to efforts to achieve the United Nations Sustainable Development Goals. However, overexploitation remains a major threat to many wild species. Ensuring and enhancing the sustainability of use of wild species is thus essential for human well-being and biodiversity conservation. Globally, the use of wild species is increasing due to growing human demand and efficiency, but its sustainability varies and depends on the social-ecological contexts in which the use occurs. Multiple environmental and social (including economic) drivers affect the sustainability of use of wild species, posing major current and future challenges. In particular, climate change has already increased the vulnerability of many uses and is expected to increase it further in the coming decades, while global and illegal trades are, in many cases, key drivers of unsustainability. There is no single “silver bullet” policy to address these and other major challenges in the sustainable use of wild species. Rather, effective policies need to integrate inclusive actions at multiple scales that adopt right-based approaches, pay attention to equitable distribution of access and costs and benefits, employ participatory processes, strengthen monitoring programs, build robust customary or government institutions and support context-specific policies, as well as adaptive management.http://www.elsevier.com/locate/gloenvchahj2023Plant Production and Soil Scienc

    Stemness of the Organ of Corti Relates to the Epigenetic Status of Sox2 Enhancers

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    In the adult mammalian auditory epithelium, the organ of Corti, loss of sensory hair cells results in permanent hearing loss. The underlying cause for the lack of regenerative response is the depletion of otic progenitors in the cell pool of the sensory epithelium. Here, we show that an increase in the sequence-specific methylation of the otic Sox2 enhancers NOP1 and NOP2 is correlated with a reduced self-renewal potential in vivo and in vitro; additionally, the degree of methylation of NOP1 and NOP2 is correlated with the dedifferentiation potential of postmitotic supporting cells into otic stem cells. Thus, the stemness the organ of Corti is related to the epigenetic status of the otic Sox2 enhancers. These observations validate the continued exploration of treatment strategies for dedifferentiating or reprogramming of differentiated supporting cells into progenitors to regenerate the damaged organ of Corti

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

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    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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