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1.
Phys Rev Lett ; 133(10): 101903, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39303248

RESUMO

New results are presented on a high-statistics measurement of Collins and Sivers asymmetries of charged hadrons produced in deep inelastic scattering of muons on a transversely polarized ^{6}LiD target. The data were taken in 2022 with the COMPASS spectrometer using the 160 GeV muon beam at CERN, statistically balancing the existing data on transversely polarized proton targets. The first results from about two-thirds of the new data have total uncertainties smaller by up to a factor of three compared to the previous deuteron measurements. Using all the COMPASS proton and deuteron results, both the transversity and the Sivers distribution functions of the u and d quark, as well as the tensor charge in the measured x range are extracted. In particular, the accuracy of the d quark results is significantly improved.

2.
Phys Rev Lett ; 133(7): 071902, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39213572

RESUMO

The COMPASS Collaboration performed measurements of the Drell-Yan process in 2015 and 2018 using a 190 GeV/c π^{-} beam impinging on a transversely polarized ammonia target. Combining the data of both years, we present final results on the amplitudes of five azimuthal modulations, which correspond to transverse-spin-dependent azimuthal asymmetries (TSAs) in the dimuon production cross section. Three of them probe the nucleon leading-twist Sivers, transversity, and pretzelosity transverse-momentum dependent (TMD) parton distribution functions (PDFs). The other two are induced by subleading effects. These TSAs provide unique new inputs for the study of the nucleon TMD PDFs and their universality properties. In particular, the Sivers TSA observed in this measurement is consistent with the fundamental QCD prediction of a sign change of naive time-reversal-odd TMD PDFs when comparing the Drell-Yan process with deep inelastic scattering. Also, within the context of model predictions, the observed transversity TSA is consistent with the expectation of a sign change for the Boer-Mulders function.

3.
Plant Biol (Stuttg) ; 26(4): 560-567, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520244

RESUMO

Pigeon pea (Cajanus cajan) is widely cultivated for its nutritional and medicinal value yet remains an orphan crop as productivity has not been improved because of a lack of genome and non-coding genome information. Non-coding RNAs, like miRNAs and long non-coding RNAs (lncRNAs), are involved in regulation of growth, metabolism, development, and stress response, and have a critical role in post-transcriptional gene regulation (PTGR). We attempted to elucidate the roles of miRNAs and lncRNAs in pigeon pea through experimental validation of computationally predicted miRNAs and lncRNAs and targets of miRNAs on mRNAs. We experimentally validated 20 miRNAs and 11 lncRNAs. We predicted cleavage sites of three miRNA targets: serine/threonine-protein kinase, polygalacturonase, beta-galactosidase. We identified 469 targets of 265 miRNAs and their functional annotations using computational methods. We built a miRNA-mRNA-lncRNA network model, with the miRNAs targeting both mRNAs and lncRNAs, to obtain information on the interplay of these three molecules. A confirmed interaction through experimental validation was established between miRNA, namely cca-miR1535a targeting the mRNA for beta-galactosidase, as well as the lncRNA cca-lnc-020033. Our findings increase knowledge of the non-coding genome of pigeon pea and their roles in PTGR and in improving agronomic traits of this pulse crop.


Assuntos
Cajanus , Regulação da Expressão Gênica de Plantas , MicroRNAs , RNA Longo não Codificante , RNA Mensageiro , RNA de Plantas , Cajanus/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética
4.
Phys Rev Lett ; 127(8): 082501, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477443

RESUMO

The COMPASS Collaboration experiment recently discovered a new isovector resonancelike signal with axial-vector quantum numbers, the a_{1}(1420), decaying to f_{0}(980)π. With a mass too close to and a width smaller than the axial-vector ground state a_{1}(1260), it was immediately interpreted as a new light exotic meson, similar to the X, Y, Z states in the hidden-charm sector. We show that a resonancelike signal fully matching the experimental data is produced by the decay of the a_{1}(1260) resonance into K^{*}(→Kπ)K[over ¯] and subsequent rescattering through a triangle singularity into the coupled f_{0}(980)π channel. The amplitude for this process is calculated using a new approach based on dispersion relations. The triangle-singularity model is fitted to the partial-wave data of the COMPASS experiment. Despite having fewer parameters, this fit shows a slightly better quality than the one using a resonance hypothesis and thus eliminates the need for an additional resonance in order to describe the data. We thereby demonstrate for the first time in the light-meson sector that a resonancelike structure in the experimental data can be described by rescattering through a triangle singularity, providing evidence for a genuine three-body effect.

5.
Sci Total Environ ; 726: 138600, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32305771

RESUMO

Existing flood modeling studies over coastal catchments involving different combinations of model chain setup imparting complex information fails to entail the needs of policy or decision-makers. Thus, a comprehensive framework that pertains to the requirements of practitioners and provides more perspicuous flood hazard information is required. In this paper, a novel approach translating complex flood hazard information in the form of decision priority maps derived using a rational combination of models (physical and statistical) is elucidated at the finest administrative scale. The proposed methodology is illustrated over a highly flood-prone deltaic region in Mahanadi River Basin, India, to characterize impacts of climate change for a 1:100 years return period flood event under future conditions (2026-2055). The modeled flood events are further analyzed to capture the transformation dynamics of flood hazard classes (FHCs) in near-future, for prioritizing areas with greater hazard potential. Interestingly, the results capture a high transformation characteristic from low to high FHCs in agriculture-dominated areas, which are significantly greater than the areas experiencing flood hazard reduction. The results show a significant increase of 12.5% and 27.35% in areas with high FHCs under RCP4.5 and RCP8.5 scenarios, respectively. Moreover, a notable climate change response is indicated under both climate change scenarios, with approximately 22% (RCP4.5) and 25% (RCP8.5) in villages showing a drastic increment in flood hazard magnitude. The results thus highlight the importance of identifying and prioritizing the areas for flood adaptation where a relative change in flood hazard potential is higher due to climate change. Therefore, we conclude that this study can provide an insight into the implication of new approaches for effective communication of flood information by bridging the gaps between scientific communities and decision-makers in appraisal for better flood adaptation measures.

6.
Phys Rev Lett ; 119(11): 112002, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28949229

RESUMO

The first measurement of transverse-spin-dependent azimuthal asymmetries in the pion-induced Drell-Yan (DY) process is reported. We use the CERN SPS 190 GeV/c π^{-} beam and a transversely polarized ammonia target. Three azimuthal asymmetries giving access to different transverse-momentum-dependent (TMD) parton distribution functions (PDFs) are extracted using dimuon events with invariant mass between 4.3 GeV/c^{2} and 8.5 GeV/c^{2}. Within the experimental uncertainties, the observed sign of the Sivers asymmetry is found to be consistent with the fundamental prediction of quantum chromodynamics (QCD) that the Sivers TMD PDFs extracted from DY have a sign opposite to the one extracted from semi-inclusive deep-inelastic scattering (SIDIS) data. We present two other asymmetries originating from the pion Boer-Mulders TMD PDFs convoluted with either the nucleon transversity or pretzelosity TMD PDFs. A recent COMPASS SIDIS measurement was obtained at a hard scale comparable to that of these DY results. This opens the way for possible tests of fundamental QCD universality predictions.

7.
Methods Enzymol ; 574: 149-165, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27423861

RESUMO

The density and diversity of posttranslational modifications (PTMs) observed in histone proteins typically limit their purification to homogeneity from biological sources. Access to quantities of uniformly modified histones is, however, critical for investigating the downstream effects of histone PTMs on chromatin-templated processes. Therefore, a number of semisynthetic methodologies have been developed to generate histones bearing precisely defined PTMs or close analogs thereof. In this chapter, we present two optimized and rapid strategies for generating functional analogs of site-specifically acetylated and sumoylated histones. First, we describe a convergent strategy to site-specifically attach the small ubiquitin-like modifier-3 (SUMO-3) protein to the site of Lys12 in histone H4 by means of a disulfide linkage. We then describe the generation of thialysine analogs of histone H3 acetylated at Lys14 or Lys56, using thiol-ene coupling chemistry. Both strategies afford multimilligram quantities of uniformly modified histones that are easily incorporated into mononucleosomes and nucleosome arrays for biophysical and biochemical investigations. These methods are readily extendable to any desired sites in the four core nucleosomal histones and their variant forms.


Assuntos
Histonas/química , Processamento de Proteína Pós-Traducional , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/química , Acetilação , Animais , Clonagem Molecular/métodos , Cisteína/análogos & derivados , Cisteína/química , Dissulfetos/química , Histonas/genética , Humanos , Lisina/análogos & derivados , Lisina/química , Modelos Moleculares , Mutagênese Sítio-Dirigida/métodos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Sumoilação , Ubiquitinas/síntese química , Ubiquitinas/química , Ubiquitinas/genética
8.
Sci Total Environ ; 468-469 Suppl: S132-8, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23800620

RESUMO

Indian Ganga Basin (IGB), one of the most densely populated areas in the world, is facing a significant threat to food grain production, besides increased yield gap between actual and potential production, due to climate change. We have analyzed the spatial variability of climate change impacts on rice and wheat yields at three different locations representing the upper, middle and lower IGB. The DSSAT model is used to simulate the effects of climate variability and climate change on rice and wheat yields by analyzing: (i) spatial crop yield response to current climate, and (ii) impact of a changing climate as projected by two regional climate models, REMO and HadRM3, based on SRES A1B emission scenarios for the period 2011-2040. Results for current climate demonstrate a significant gap between actual and potential yield for upper, middle and lower IGB stations. The analysis based on RCM projections shows that during 2011-2040, the largest reduction in rice and wheat yields will occur in the upper IGB (reduction of potential rice and wheat yield respectively by 43.2% and 20.9% by REMO, and 24.8% and 17.2% by HadRM3). In the lower IGB, however, contrasting results are obtained, with HadRM3 based projections showing an increase in the potential rice and wheat yields, whereas, REMO based projections show decreased potential yields. We discuss the influence of agro-climatic factors; variation in temperature, length of maturity period and leaf area index which are responsible for modeled spatial variability in crop yield response within the IGB.


Assuntos
Agricultura/estatística & dados numéricos , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Clima , Monitoramento Ambiental , Índia , Modelos Teóricos , Temperatura
9.
J Indian Med Assoc ; 110(9): 612-4, 622, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23741833

RESUMO

The clinical consequences of HIV infection encompass a wide spectrum. Early recognition of persons who have HIV will help in early interventions to halt or slow down the progress of HIV disease and to extend fruitful lives.This cross-sectional study was conducted among patients referred to the voluntary counselling and testing centre (VCTC) from various departments in North Bengal Medical College & Hospital, Darjeeling, West Bengal, to find out the pattern of disease/symptoms, high risk behaviour (HRB) for HIV, and HIV serostatus among the hospital patients. Following the guidelines prescribed by the National AIDS Control Organisation (NACO), anonymous data were collected through interview from 407 individuals. Where specific diagnosis of a disease was obtained, it was analysed as mutually exclusive disease; and where specific diagnosis was not obtained, mutually exclusive symptoms were considered for analysis.The major diseases/symptoms observed among those patients were tuberculosis in 32.19%, STD in 29.97%, prolonged unexplained fever in 19.41% of patients. The overall rate of HIV seroreactivity was 17.44%. The HIV serostatus by disease/symptoms showed that 32.91% of patients with prolonged unexplained fever were HIV seroreactive; the rate was 12.90% among patients with skin diseases, 12.29% in STD and 12.21% in tuberculosis patients. Overall, 270 patients (66.34%) had HRB for HIV/AIDS.The rate of HIV seroreactivity was more among patients who had HRB for HIV/ AIDS and who were referred from indoor departments (23.24%) compared to outdoor departments (13.65%).The patients suffering from prolonged unexplained fever need greater attention for HIV screening. Early detection of HIV positive patients makes Intervention possible at a very early stage and this can slow down/block the progress of HIV disease and, as a result, can extend fruitful life.


Assuntos
Soropositividade para HIV/diagnóstico , Soropositividade para HIV/epidemiologia , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Febre de Causa Desconhecida/epidemiologia , Humanos , Índia/epidemiologia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Ocupações , Estudos Soroepidemiológicos , Infecções Sexualmente Transmissíveis/epidemiologia , Abuso de Substâncias por Via Intravenosa , Centros de Atenção Terciária , Reação Transfusional , Tuberculose Pulmonar/epidemiologia , Sexo sem Proteção , Adulto Jovem
10.
Afr Health Sci ; 11(1): 128-33, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21572868

RESUMO

BACKGROUND: Cold chain maintenance is an essential activity to maintain the potency of vaccines and to prevent adverse events following immunization. One baseline study highlighted the unsatisfactory cold chain status in city of Kolkata in India. OBJECTIVES: To assess the changes which occurred in the cold chain status after the intervention undertaken to improve the status and also to assess the awareness of the cold chain handlers regarding cold chain maintenance. METHODS: Intervention consisted of reorganization of cold chain points and training of health manpower in Kolkata Municipal area regarding immunization and cold chain following the guidelines as laid by Govt of India. Reevaluation of cold chain status was done at 20 institutions selected by stratified systematic random sampling after the intervention. The results were compared with baseline survey. RESULTS: Significant improvement had been observed in correct placing of cold chain equipment, maintenance of stock security, orderly placing of ice packs, diluents and vaccines inside the equipment, temperature recording and maintenance. But awareness and skill of cold chain handlers regarding basics of cold chain maintenance was not satisfactory. CONCLUSIONS: The success of intervention included significant improvement of cold chain status including creation of a designated cold chain handler. The gaps lay in non-availability of non-electrical cold chain equipment and separate cold chain room, policy makers should stress. Cold chain handlers need reorientation training regarding heat & cold sensitive vaccines, preventive maintenance and correct contingency plan.


Assuntos
Armazenamento de Medicamentos/normas , Refrigeração/normas , Vacinas/provisão & distribuição , Temperatura Baixa , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Índia , Competência Profissional , Avaliação de Programas e Projetos de Saúde , Garantia da Qualidade dos Cuidados de Saúde , Refrigeração/métodos , População Urbana
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