Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Assunto principal
Intervalo de ano de publicação
1.
Nutrients ; 15(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37049458

RESUMO

Given the current lack of studies, the primary purpose of this study was to investigate the effects of black maca supplementation intake on changes in physical strength and inflammatory markers among elite athletes. Forty-four elite athletes were recruited for the present study. They included shooting athletes, racket sports athletes, and fin swimming athletes. The intake capsules contained 2500 mg of 100% concentrated black maca extract. Participants were instructed to take one capsule twice a day for eight weeks with pure water. Changes were seen in the ATP-PC systems and aerobic energy systems, particularly in the fin swimming athletes requiring aerobic energy systems. This effect is caused by increased antioxidant activity and influenced mitochondrial biosynthesis regulatory factors due to black maca supplementation intake. These findings provide preliminary evidence that elite athletes will benefit from taking black maca to improve their inflammation levels and physical fitness.


Assuntos
Lepidium , Humanos , Masculino , Aptidão Física , Atletas , Natação , Suplementos Nutricionais
2.
Food Nutr Res ; 672023.
Artigo em Inglês | MEDLINE | ID: mdl-38187794

RESUMO

Background: The aim of this study was to investigate the changes in isokinetic muscular performance among female adolescent elite handball athletes with the supplementation of Black Maca (BM). Methods: Eight elite handball athletes were recruited for the present study. The intake capsules contained 2,500 mg of 100% concentrated BM extract and a placebo each, for 4 weeks. Isokinetic muscular performance and physical fitness were measured three times at 4-week intervals after the intake of BM and placebo, including baseline. Results: The one-way Analysis of Variance (ANOVA) analysis showed a significant improvement in 20 m-shuttle run (P < 0.001), 30°/s flexor (P < 0.01), and 120°/s flexor (P < 0.01) in isokinetic muscle function of the trunk, and 180°/s right extensor (P < 0.05), 180°/s left extensor (P < 0.05), and 180°/s left flexor (P < 0.01) in isokinetic muscle function of the knee, after BM supplementation. Post-hoc analysis indicated that the BM group had significantly higher results compared to the baseline and placebo groups in terms of 20 m-shuttle run, 30°/s flexor and 120°/s flexor of the trunk, 180°/s right extensor, 180°/s left extensor, and 180°/s left flexor of the knee. Conclusion: BM supplementation can have a positive effect on improving the performance of elite handball players who engage in high-intensity movements by enhancing their isokinetic muscle function and endurance.

3.
Phys Rev Lett ; 122(9): 091801, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932553

RESUMO

We propose a novel kinematic method to expedite the discovery of the double Higgs (hh) production in the ℓ^{+}ℓ^{-}bb[over ¯]+E_{T} final state. We make full use of recently developed kinematic variables, as well as the variables "Topness" for the dominant background (top quark pair production) and "Higgsness" for the signal. We obtain a significant increase in sensitivity compared to the previous analyses that used sophisticated algorithms like boosted decision trees or neutral networks. The method can be easily generalized to resonant hh production as well as other nonresonant channels.

4.
Phys Rev Lett ; 119(26): 261801, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29328730

RESUMO

We propose a spectral decomposition to systematically extract information of dark matter at hadron colliders. The differential cross section of events with missing transverse energy (E_{T}) can be expressed by a linear combination of basis functions. In the case of s-channel mediator models for dark matter particle production, basis functions are identified with the differential cross sections of subprocesses of virtual mediator and visible particle production while the coefficients of basis functions correspond to dark matter invariant mass distribution in the manner of the Källén-Lehmann spectral decomposition. For a given E_{T} data set and mediator model, we show that one can differentiate a certain dark matter-mediator interaction from another through spectral decomposition.

5.
Phys Rev Lett ; 116(15): 151805, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27127960

RESUMO

We discuss nonstandard interpretations of the 750 GeV diphoton excess recently reported by the ATLAS and CMS Collaborations which do not involve a new, relatively broad resonance with a mass near 750 GeV. Instead, we consider the sequential cascade decay of a much heavier, possibly quite narrow, resonance into two photons along with one or more additional particles. The resulting diphoton invariant mass signal is generically rather broad, as suggested by the data. We examine three specific event topologies-the "antler," the "sandwich," and the two-step cascade decay-and show that they all can provide a good fit to the observed published data. In each case, we delineate the preferred mass parameter space selected by the best fit. In spite of the presence of extra particles in the final state, the measured diphoton p_{T} spectrum is moderate due to its anticorrelation with the diphoton invariant mass. We comment on the future prospects of discriminating with higher statistics between our scenarios, as well as from more conventional interpretations.

6.
Phys Rev Lett ; 111(4): 041801, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23931355

RESUMO

The latest results from the ATLAS and CMS experiments at the CERN Large Hadron Collider unequivocally confirm the existence of a resonance X with mass near 125 GeV which could be the Higgs boson of the standard model. Measuring the properties (quantum numbers and couplings) of this resonance is of paramount importance. Initial analyses by the LHC Collaborations disfavor specific alternative benchmark hypotheses, e.g., pure pseudoscalars or gravitons. However, this is just the first step in a long-term program of detailed measurements. We consider the most general set of operators in the decay channels X→ZZ, WW, Zγ, γγ, and derive the constraint implied by the measured rate. This allows us to provide a useful parametrization of the orthogonal independent Higgs coupling degrees of freedom as coordinates on a suitably defined sphere.

7.
Phys Rev Lett ; 107(6): 061801, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902311

RESUMO

We present a general solution to the long-standing problem of determining the masses of pair-produced, semi-invisibly decaying particles at hadron colliders. We define two new transverse kinematic variables M(CT)(⊥) and M(CT)(∥), which are suitable one-dimensional projections of the contransverse mass M(CT). We derive analytical formulas for the boundaries of the kinematically allowed regions in the (M(CT)(⊥),M(CT)(∥)) and (M(CT)(⊥),M(CT)) parameter planes and introduce suitable variables D(CT)(∥) and D(CT) to measure the distance to those boundaries on an event per event basis. We show that the masses can be reliably extracted from the end-point measurements of M(CT)(⊥)(max) and D(CT)(min) (or D(CT)(∥)(min)). We illustrate our method with dilepton tt events at the LHC.

8.
Phys Rev Lett ; 105(5): 051802, 2010 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-20867907

RESUMO

We propose a new model-independent technique for mass measurements in missing energy events at hadron colliders. We illustrate our method with the most challenging case of a single-step decay chain. We consider inclusive same-sign chargino pair production in supersymmetry, followed by leptonic decays to sneutrinos χ+ χ+ → ℓ+ ℓ'+ ν(ℓ)ν(ℓ') and invisible decays ν(ℓ) → ν(ℓ) χ(1)(0). We introduce two one-dimensional decompositions of the Cambridge MT2 variable: M(T2∥) and M(T2⊥), on the direction of the upstream transverse momentum P→T and the direction orthogonal to it, respectively. We show that the sneutrino mass Mc can be measured directly by minimizing the number of events N(Mc) in which MT2 exceeds a certain threshold, conveniently measured from the end point M(T2⊥)(max) (Mc).

9.
Phys Rev Lett ; 105(22): 221801, 2010 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-21231378

RESUMO

We apply a model-independent, agnostic approach to the collider phenomenology of supersymmetry, in which all mass parameters are taken as free inputs at the weak scale. We consider the gauginos, Higgsinos, and the first two generations of sleptons and squarks, and analyze all possible mass hierarchies among them (4×8!=161,280 in total) in which the lightest superpartner is neutral, leading to missing energy. In each case, we identify the full set of the dominant decay chains originating from the lightest colored superpartner. Our exhaustive search reveals several quite dramatic yet unexplored multilepton signatures with up to 8 isolated leptons (plus possibly up to 2 massive gauge or Higgs bosons) in the final state. Such events are spectacular, background-free for all practical purposes, and may lead to a discovery in the very early stage (∼10 pb(-1)) of LHC operations at 7 TeV.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...