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1.
Phys Rev Lett ; 133(13): 131801, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39392959

RESUMEN

We measure the complete set of angular coefficients J_{i} for exclusive B[over ¯]→D^{*}ℓν[over ¯]_{ℓ} decays (ℓ=e, µ). Our analysis uses the full 711 fb^{-1} Belle dataset with hadronic tag-side reconstruction. The results allow us to extract the form factors describing the B[over ¯]→D^{*} transition and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cb}|. Using recent lattice QCD calculations for the hadronic form factors, we find |V_{cb}|=(40.7±0.7)×10^{-3} using the Boyd-Grinstein-Lebed parametrization, compatible with determinations from inclusive semileptonic decays. We search for lepton flavor universality violation as a function of the hadronic recoil parameter w and investigate the differences of the electron and muon angular distributions. We find no deviation from standard model expectations.

2.
Phys Rev Lett ; 133(8): 081801, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39241732

RESUMEN

We present a comprehensive study of B^{0}→ωω decays using 772×10^{6} BB[over ¯] pairs collected with the Belle detector at the KEKB e^{+}e^{-} collider. This process is a suppressed charmless decay into two vector mesons and can exhibit interesting polarization and CP violation. The decay is observed for the first time with a significance of 7.9 standard deviations. We measure a branching fraction B=(1.53±0.29±0.17)×10^{-6}, a fraction of longitudinal polarization f_{L}=0.87±0.13±0.13, and a time-integrated CP asymmetry A_{CP}=-0.44±0.43±0.11, where the first uncertainties listed are statistical and the second are systematic. This is the first observation of B^{0}→ωω and the first measurements of f_{L} and A_{CP} for this decay.

3.
Kathmandu Univ Med J (KUMJ) ; 22(86): 215-220, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39328114

RESUMEN

Background Nutrition is associated with oral health and any changes in dietary habits have impacted nutritional profiles which in turn influences oral health status. Objective To assess the oral health and nutritional status among school teachers in Dharamshala city, Himachal Pradesh. Method A descriptive cross-sectional study was undertaken with interviews and documented using a structured and adapted WHO proforma. The oral health was assessed by using WHO oral assessment form 2013 (by tooth surfaces) and the nutritional status by using five day dietary recall and scored according to dental health dietary score. The dental health dietary scores included food group scores (FGS), nutritional evaluation score (NES), decay promoting potential scores (DPPS) for all five days. Result Almost, two third of the school teachers in both types of schools had an excellent Food Group Score (FGS) on all five days of dietary recalls. The mean total Decay Promoting Potential Score (DPPS) was 23.33±3.20 (minute). Approximately onethird of the teachers in both types of schools had DPPS scores within the "watch out" zone of dietary recall, ranging 15 or more on each day. The mean DMFT was 3.79±2.52 with mean total decayed teeth as 1.35±2.03. Similarly, the mean DMFS was 9.68±7.95 with the mean total decayed surfaces as 1.81±2.94. Conclusion The frequency of essential food groups remained consistent throughout the fiveday dietary recall period. Carbohydrates formed the primary component whereas proteins were frequently missing from the diets. Frequent absence of protein intake in diet increased loss of attachment.


Asunto(s)
Estado Nutricional , Salud Bucal , Maestros , Humanos , Estudios Transversales , Salud Bucal/estadística & datos numéricos , India/epidemiología , Femenino , Masculino , Adulto , Maestros/estadística & datos numéricos , Persona de Mediana Edad , Conducta Alimentaria
4.
Phys Rev Lett ; 133(7): 071802, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39213574

RESUMEN

We report the results of the first search for B^{-} decays to the Ξ[over ¯]_{c}^{0}Λ[over ¯]_{c}^{-} final state using 711 fb^{-1} of data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The results are interpreted in terms of both direct baryon-number-violating B^{-} decay and Ξ_{c}^{0}-Ξ[over ¯]_{c}^{0} oscillations which follow the standard model decay B^{-}→Ξ_{c}^{0}Λ[over ¯]_{c}^{-}. We observe no evidence for baryon number violation and set the 95% confidence-level upper limits on the ratio of baryon-number-violating and standard model branching fractions B(B^{-}→Ξ[over ¯]_{c}^{0}Λ[over ¯]_{c}^{-})/B(B^{-}→Ξ_{c}^{0}Λ[over ¯]_{c}^{-}) to be <2.7% and on the effective angular frequency of mixing ω in Ξ_{c}^{0}-Ξ[over ¯]_{c}^{0} oscillations to be <0.76 ps^{-1} (equivalent to τ_{mix}>1.3 ps).

5.
PLoS One ; 18(10): e0292955, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37851600

RESUMEN

Coriander, fenugreek, nigella etc. are collectively known as seed spices. They are "High value and low volume crops" and considered cash crops for the growers of arid and semi-arid regions of India. Coriander, fenugreek and nigella are grown during the rabi season and take hardly 130-140 days to attain full maturity. In this context, farmers are not able to develop income from available arable land round the year, even though they have sufficient resources as well as manpower. Therefore, coriander, fenugreek and nigella-based cropping systems, four of each (total 12) were evaluated during 3 consecutive years (2019-20 to 2021-22) for their productivity, resource-use efficiency, economics and soil fertility. The results showed that among the seed spices-based cropping systems, maximum system productivity (5193 kg ha-1), production efficiency (18.81 kg ha-1 day-1), water-use efficiency (2.31 kg ha-1 mm-1), economic efficiency (11.85 US $ ha-1 day-1), net return (3270 US $ ha-1), benefit:cost ratio (3.27) and available N (165.6 kg ha-1) were observed under nigella-green coriander-mungbean cropping system. Hence, seed spices growers are recommended to adopt nigella-green coriander-mungbean cropping system in order to realize better productivity, resource-use efficiency, soil fertility and profitability.


Asunto(s)
Fabaceae , Suelo , Agricultura/métodos , Clima Desértico , India
6.
Phys Rev Lett ; 131(12): 121802, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37802942

RESUMEN

We report the first search for a nonstandard-model resonance decaying into τ pairs in e^{+}e^{-}→µ^{+}µ^{-}τ^{+}τ^{-} events in the 3.6-10 GeV/c^{2} mass range. We use a 62.8 fb^{-1} sample of e^{+}e^{-} collisions collected at a center-of-mass energy of 10.58 GeV by the Belle II experiment at the SuperKEKB collider. The analysis probes three different models predicting a spin-1 particle coupling only to the heavier lepton families, a Higgs-like spin-0 particle that couples preferentially to charged leptons (leptophilic scalar), and an axionlike particle, respectively. We observe no evidence for a signal and set exclusion limits at 90% confidence level on the product of cross section and branching fraction into τ pairs, ranging from 0.7 to 24 fb, and on the couplings of these processes. We obtain world-leading constraints on the couplings for the leptophilic scalar model for masses above 6.5 GeV/c^{2} and for the axionlike particle model over the entire mass range.

7.
Phys Rev Lett ; 131(5): 051804, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595249

RESUMEN

We present the first measurement of the ratio of branching fractions of inclusive semileptonic B-meson decays, R(X_{e/µ})=B(B→Xeν)/B(B→Xµν), a precision test of electron-muon universality, using data corresponding to 189 fb^{-1} from electron-positron collisions collected with the Belle II detector. In events where the partner B meson is fully reconstructed, we use fits to the lepton momentum spectra above 1.3 GeV/c to obtain R(X_{e/µ})=1.007±0.009(stat)±0.019(syst), which is the most precise lepton-universality test of its kind and agrees with the standard-model expectation.

8.
Phys Rev Lett ; 130(26): 261802, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37450824

RESUMEN

We present a search for the lepton flavor violating decays B^{+}→K^{+}τ^{±}ℓ^{∓}, with ℓ=(e,µ), using the full data sample of 772×10^{6} BB[over ¯] pairs recorded by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We use events in which one B meson is fully reconstructed in a hadronic decay mode. We find no evidence for B^{±}→K^{±}τℓ decays and set upper limits on their branching fractions at the 90% confidence level in the (1-3)×10^{-5} range. The obtained limits are the world's best results.

9.
Ultrasound J ; 15(1): 24, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37165284

RESUMEN

BACKGROUND: Femoral vein Doppler (FVD) is simpler than the VExUS score which is a multimodal scoring system based on combination of IVC diameter, hepatic venous Doppler, portal vein pulsatility and renal vein Doppler, may be useful in assessing right ventricular overload and signs of venous congestion. There is limited data on the relationship between FVD and VExUS score. RESULTS: Adult post-cardiac surgery patients were assessed for venous congestion using the VExUS score and FVD. Agreement between VExUS and FVD was studied using Kappa test, sensitivity, specificity, PPV and NPV for VExUS and FVD was calculated keeping CVP as gold standard. In total, 107 patients were enrolled, with a mean age of 55.67 ± 12.76. The accuracy of VExUS and FVD for detecting venous congestion was 80.37 (95% CI of 71.5 to 87.4) and 74.7 (95% CI of 65.4 to 82.6), respectively. The level of agreement between FVD and VExUS was moderate (Kappa value of 0.62, P < 0.001) while the agreement between FVD and CVP was weak (Kappa value of 0.49, P < 0.001). CONCLUSION: FVD has good accuracy for detecting venous congestion and shows moderate agreement with VExUS grading. With potentially easier physical accessibility and a shorter learning curve for novices, it may be a simple and valuable tool for assessing venous congestion.

10.
Phys Rev Lett ; 130(7): 071802, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36867815

RESUMEN

An absolute measurement of the Λ_{c}^{+} lifetime is reported using Λ_{c}^{+}→pK^{-}π^{+} decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the ϒ(4S) resonance, is 207.2 fb^{-1}. The result, τ(Λ_{c}^{+})=203.20±0.89±0.77 fs, where the first uncertainty is statistical and the second systematic, is the most precise measurement to date and is consistent with previous determinations.

11.
Phys Rev Lett ; 130(3): 031901, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36763394

RESUMEN

We present the study of B[over ¯]^{0}→Σ_{c}(2455)^{0,++}π^{±}p[over ¯] decays based on 772×10^{6} BB[over ¯] events collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The Σ_{c}(2455)^{0,++} candidates are reconstructed via their decay to Λ_{c}^{+}π^{∓} and Λ_{c}^{+} decays to pK^{-}π^{+}, pK_{S}^{0}, and Λπ^{+} final states. The corresponding branching fractions are measured to be B(B[over ¯]^{0}→Σ_{c}(2455)^{0}π^{+}p[over ¯])=(1.09±0.06±0.07)×10^{-4} and B(B[over ¯]^{0}→Σ_{c}(2455)^{++}π^{-}p[over ¯])=(1.84±0.11±0.12)×10^{-4}, which are consistent with the world average values with improved precision. A new structure is found in the M_{Σ_{c}(2455)^{0,++}π^{±}} spectrum with a significance of 4.2σ including systematic uncertainty. The structure is possibly an excited Λ_{c}^{+} and is tentatively named Λ_{c}(2910)^{+}. Its mass and width are measured to be (2913.8±5.6±3.8) MeV/c^{2} and (51.8±20.0±18.8) MeV, respectively. The products of branching fractions for the Λ_{c}(2910)^{+} are measured to be B(B[over ¯]^{0}→Λ_{c}(2910)^{+}p[over ¯])×B(Λ_{c}(2910)^{+}→Σ_{c}(2455)^{0}π^{+})=(9.5±3.6±1.6)×10^{-6} and B(B[over ¯]^{0}→Λ_{c}(2910)^{+}p[over ¯])×B(Λ_{c}(2910)^{+}→Σ_{c}(2455)^{++}π^{-})=(1.24±0.35±0.10)×10^{-5}. Here, the first and second uncertainties are statistical and systematic, respectively.

12.
Phys Rev Lett ; 128(8): 081804, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35275679

RESUMEN

We search for a light Higgs boson (A^{0}) decaying into a τ^{+}τ^{-} or µ^{+}µ^{-} pair in the radiative decays of ϒ(1S). The production of ϒ(1S) mesons is tagged by ϒ(2S)→π^{+}π^{-}ϒ(1S) transitions, using 158×10^{6} ϒ(2S) events accumulated with the Belle detector at the KEKB asymmetric energy electron-positron collider. No significant A^{0} signals in the mass range from the τ^{+}τ^{-} or µ^{+}µ^{-} threshold to 9.2 GeV/c^{2} are observed. We set the upper limits at 90% credibility level (C.L.) on the product branching fractions for ϒ(1S)→γA^{0} and A^{0}→τ^{+}τ^{-} varying from 3.8×10^{-6} to 1.5×10^{-4}. Our results represent an approximately twofold improvement on the current world best upper limits for the ϒ(1S)→γA^{0}(→τ^{+}τ^{-}) production. For A^{0}→µ^{+}µ^{-}, the upper limits on the product branching fractions for ϒ(1S)→γA^{0} and A^{0}→µ^{+}µ^{-} are at the same level as the world average limits, and vary from 3.1×10^{-7} to 1.6×10^{-5}. The upper limits at 90% credibility level on the Yukawa coupling f_{ϒ(1S)} and mixing angle sinθ_{A^{0}} are also given.

13.
Phys Rev Lett ; 127(21): 211801, 2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34860075

RESUMEN

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72 fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst) fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst) fs, are the most precise to date and are consistent with previous determinations.

14.
Phys Rev Lett ; 127(12): 121803, 2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34597085

RESUMEN

Using data samples of 89.5 and 711 fb^{-1} recorded at energies of sqrt[s]=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e^{+}e^{-} collider, we report measurements of branching fractions of semileptonic decays Ξ_{c}^{0}→Ξ^{-}ℓ^{+}ν_{ℓ} (ℓ=e or µ) and the CP-asymmetry parameter of Ξ_{c}^{0}→Ξ^{-}π^{+} decay. The branching fractions are measured to be B(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})=(1.31±0.04±0.07±0.38)% and B(Ξ_{c}^{0}→Ξ^{-}µ^{+}ν_{µ})=(1.27±0.06±0.10±0.37)%, and the decay parameter α_{Ξπ} is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/B(Ξ_{c}^{0}→Ξ^{-}µ^{+}ν_{µ}) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter A_{CP}=(α_{Ξ^{-}π^{+}}+α_{Ξ[over ¯]^{+}π^{-}})/(α_{Ξ^{-}π^{+}}-α_{Ξ[over ¯]^{+}π^{-}})=0.024±0.052±0.014 is found to be consistent with zero. The first and the second uncertainties above are statistical and systematic, respectively, while the third ones arise due to the uncertainty of the Ξ_{c}^{0}→Ξ^{-}π^{+} branching fraction.

15.
Phys Rev Lett ; 126(16): 161801, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33961476

RESUMEN

We present a measurement of R_{K^{*}}, the branching fraction ratio B(B→K^{*}µ^{+}µ^{-})/B(B→K^{*}e^{+}e^{-}), for both charged and neutral B mesons. The ratio for the charged case R_{K^{*+}} is the first measurement ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass q^{2}. The analysis is based on a data sample of 711 fb^{-1}, containing 772×10^{6} BB[over ¯] events, recorded at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The obtained results are consistent with standard model expectations.

16.
Phys Rev Lett ; 126(12): 122001, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33834793

RESUMEN

We report the first evidence for X(3872) production in two-photon interactions by tagging either the electron or the positron in the final state, exploring the highly virtual photon region. The search is performed in e^{+}e^{-}→e^{+}e^{-}J/ψπ^{+}π^{-}, using 825 fb^{-1} of data collected by the Belle detector operated at the KEKB e^{+}e^{-} collider. We observe three X(3872) candidates, where the expected background is 0.11±0.10 events, with a significance of 3.2σ. We obtain an estimated value for Γ[over ˜]_{γγ}B(X(3872)→J/ψπ^{+}π^{-}) assuming the Q^{2} dependence predicted by a cc[over ¯] meson model, where -Q^{2} is the invariant mass squared of the virtual photon. No X(3915)→J/ψπ^{+}π^{-} candidates are found.

17.
Bioorg Chem ; 112: 104860, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33839462

RESUMEN

Benzosuberene-sulfone (BSS) analogues have been semi-synthesized following green approaches from himachalenes, which has been extracted from essential oil of Cedrus deodara. In this process, benzosuberene in presence of different aryl or alkyl sodium sulfinates, I2 and potassium persulfate (K2S2O8) in acetonitrile-water solvent conditions gave BSS-analogues at room temperature. Under this reaction, a facile endocyclic ß-H elimination has been noticed for BSS-analogues synthesis instead of vinyl sulfones and the reason may be due to its specific structure and electronic environment. The BSS-compounds were obtained with moderate to excellent yields under mild conditions. All the compounds were computationally subjected to drug likeliness and toxicity prediction studies. Further, the synthesized molecules were evaluated under in-silico studies for their binding affinity towards the native Peroxisome Proliferator-Activated Receptor Gamma (PPARG), and two PPARG mutants (R357A and V290M). Both the mutant forms of PPARG are deficient in eliciting a response to treatment with full and partial agonists. Our computational studies suggested that the molecule 3q performed better than the standard drug (Rosiglitazone) in all three protein structures. This implies that our suggested molecule could act as a more potent antagonist to native PPARG and could also be developed to treat type-2 diabetes patients with R357A and V290M mutations, which didn't elicit any response to currently available drugs in the market.


Asunto(s)
Cedrus/química , Cumarinas/farmacología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/farmacología , Simulación del Acoplamiento Molecular , Sulfonas/farmacología , Cumarinas/química , Relación Dosis-Respuesta a Droga , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Ligandos , Estructura Molecular , Relación Estructura-Actividad , Sulfonas/química
18.
Phys Rev Lett ; 125(16): 161806, 2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33124872

RESUMEN

We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e^{+}e^{-}→γa, a→γγ in the mass range 0.2

19.
Sci Rep ; 10(1): 12643, 2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32724048

RESUMEN

Engineering material properties is key for development of smart materials and next generation nanodevices. This requires nanoscale spatial precision and control to fabricate structures/defects. Lithographic techniques are widely used for nanostructuring in which a geometric pattern on a mask is transferred to a resist by photons or charged particles and subsequently engraved on the substrate. However, direct mask-less fabrication has only been possible with electron and ion beams. That is because light has an inherent disadvantage; the diffraction limit makes it difficult to interact with matter on dimensions smaller than the wavelength of light. Here we demonstrate spatially controlled formation of nanocones on a silicon surface with a positional precision of 50 nm using femtosecond laser ablation comprising a superposition of optical vector vortex and Gaussian beams. Such control and precision opens new opportunities for nano-printing of materials using techniques such as laser-induced forward transfer and in general broadens the scope of laser processing of materials.

20.
Phys Rev Lett ; 124(12): 122001, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32281835

RESUMEN

We report the first observation of the radiative decay of the ϒ(1S) into a charmonium state. The significance of the observed signal of ϒ(1S)→γχ_{c1} is 6.3 standard deviations including systematics. The branching fraction is calculated to be B[ϒ(1S)→γχ_{c1}]=[4.7_{-1.8}^{+2.4}(stat)_{-0.5}^{+0.4}(sys)×10^{-5}]. We also searched for ϒ(1S) radiative decays into χ_{c0,2} and η_{c}(1S,2S), and set upper limits on their branching fractions. These results are obtained from a 24.9 fb^{-1} data sample collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider at a center-of-mass energy equal to the ϒ(2S) mass using ϒ(1S) tagging by the ϒ(2S)→ϒ(1S)π^{+}π^{-} transitions.

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