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1.
Phys Rev Lett ; 130(25): 251901, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37418716

RESUMO

We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510 GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510 GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02

Assuntos
Alimentos , Fótons , Movimento (Física)
2.
Phys Rev Lett ; 127(16): 162001, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34723614

RESUMO

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200 GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

4.
Phys Rev Lett ; 123(12): 122001, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31633981

RESUMO

We report on the nuclear dependence of transverse single-spin asymmetries (TSSAs) in the production of positively charged hadrons in polarized p^{↑}+p, p^{↑}+Al, and p^{↑}+Au collisions at sqrt[s_{NN}]=200 GeV. The measurements have been performed at forward rapidity (1.4<η<2.4) over the range of transverse momentum (1.8

5.
Phys Rev Lett ; 121(22): 222301, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547634

RESUMO

Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.

6.
Phys Rev Lett ; 120(6): 062302, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481251

RESUMO

Recently, multiparticle-correlation measurements of relativistic p/d/^{3}He+Au, p+Pb, and even p+p collisions show surprising collective signatures. Here, we present beam-energy-scan measurements of two-, four-, and six-particle angular correlations in d+Au collisions at sqrt[s_{NN}]=200, 62.4, 39, and 19.6 GeV. We also present measurements of two- and four-particle angular correlations in p+Au collisions at sqrt[s_{NN}]=200 GeV. We find the four-particle cumulant to be real valued for d+Au collisions at all four energies. We also find that the four-particle cumulant in p+Au has the opposite sign as that in d+Au. Further, we find that the six-particle cumulant agrees with the four-particle cumulant in d+Au collisions at 200 GeV, indicating that nonflow effects are subdominant. These observations provide strong evidence that the correlations originate from the initial geometric configuration, which is then translated into the momentum distribution for all particles, commonly referred to as collectivity.

7.
Phys Rev Lett ; 120(2): 022001, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376675

RESUMO

During 2015, the Relativistic Heavy Ion Collider (RHIC) provided collisions of transversely polarized protons with Au and Al nuclei for the first time, enabling the exploration of transverse-single-spin asymmetries with heavy nuclei. Large single-spin asymmetries in very forward neutron production have been previously observed in transversely polarized p+p collisions at RHIC, and the existing theoretical framework that was successful in describing the single-spin asymmetry in p+p collisions predicts only a moderate atomic-mass-number (A) dependence. In contrast, the asymmetries observed at RHIC in p+A collisions showed a surprisingly strong A dependence in inclusive forward neutron production. The observed asymmetry in p+Al collisions is much smaller, while the asymmetry in p+Au collisions is a factor of 3 larger in absolute value and of opposite sign. The interplay of different neutron production mechanisms is discussed as a possible explanation of the observed A dependence.

8.
J Oral Rehabil ; 44(1): 59-64, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27883209

RESUMO

Tongue function can affect both the oral and pharyngeal stages of the swallowing process, and proper tongue strength is vital for safe oropharyngeal swallowing. This trial investigated the effect of tongue-to-palate resistance training (TPRT) on tongue strength and oropharyngeal swallowing function in stroke with dysphagia patients. This trial was performed using a 4-week, two-group, pre-post-design. Participants were allocated to the experimental group (n = 18) or the control group (n = 17). The experimental group performed TPRT for 4 weeks (5 days per week) and traditional dysphagia therapy, whereas the control group performed traditional dysphagia therapy on the same schedule. Tongue strength was measured using the Iowa Oral Performance Instrument. Swallowing function was measured using the videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS) based on a videofluoroscopic swallowing study. Experimental group showed more improved in the tongue strength (both anterior and posterior regions, P = 0·009, 0·015). In addition, the experimental group showed more improved scores on the oral and pharyngeal phase of VDS (P = 0·029, 0·007), but not on the PAS (P = 0·471), compared with the control group. This study demonstrated the effectiveness of TPRT in increasing tongue muscle strength and improving swallowing function in patients with post-stroke dysphagia. Therefore, we recommend TPRT as an easy and simple rehabilitation strategy for improving swallowing in patients with dysphagia.


Assuntos
Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Palato/fisiopatologia , Treinamento Resistido , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Língua/fisiopatologia , Fenômenos Biomecânicos , Transtornos de Deglutição/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Recuperação de Função Fisiológica , Treinamento Resistido/métodos , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento
9.
Anaesthesia ; 70(4): 434-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25387428

RESUMO

Posterior neck pain following thyroidectomy is common because full neck extension is required during the procedure. We evaluated the effect of intra-operative transcutaneous electrical nerve stimulation on postoperative neck pain in patients undergoing total thyroidectomy under general anaesthesia. One hundred patients were randomly assigned to one of two groups; 50 patients received transcutaneous electrical nerve stimulation applied to the trapezius muscle and 50 patients acted as controls. Postoperative posterior neck pain and anterior wound pain were evaluated using an 11-point numerical rating scale at 30 min, 6 h, 24 h and 48 h following surgery. The numerical rating scale for posterior neck pain was significantly lower in the transcutaneous electrical nerve stimulation group compared with the control group at all time points (p < 0.05). There were no significant differences in the numerical rating scale for anterior wound pain at any time point. No adverse effects related to transcutaneous electrical nerve stimulation were observed. We conclude that intra-operative transcutaneous electrical nerve stimulation applied to the trapezius muscle reduced posterior neck pain following thyroidectomy.


Assuntos
Cuidados Intraoperatórios/métodos , Cervicalgia/prevenção & controle , Dor Pós-Operatória/prevenção & controle , Tireoidectomia/efeitos adversos , Estimulação Elétrica Nervosa Transcutânea/métodos , Adulto , Anestesia Geral , Feminino , Seguimentos , Movimentos da Cabeça , Humanos , Pessoa de Meia-Idade , Cervicalgia/etiologia , Cervicalgia/fisiopatologia , Medição da Dor/métodos , Dor Pós-Operatória/fisiopatologia , Músculos Superficiais do Dorso/fisiopatologia , Tireoidectomia/métodos , Adulto Jovem
10.
Int J Clin Pract ; 69(2): 242-50, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25363415

RESUMO

OBJECTIVES: To evaluate the dose-response relationship of tarafenacin, an antimuscarinic agent in development phase, for efficacy and safety, at daily doses of 0.2 and 0.4 mg for the treatment of overactive bladder (OAB) PATIENTS AND METHODS: This multicentre, placebo-controlled, randomised, double-blind, phase 2b study was conducted. Patients were randomised to tarafenacin 0.2 mg, tarafenacin 0.4 mg or placebo daily for 12 weeks. Adult patients with OAB for at least 6 months, with an average of ≥ 8 micturitions per day and ≥ 3 incontinence episodes or a total of ≥ 6 urgency episodes per 3 days were enrolled. The primary objective was to compare the mean changes in the number of micturitions per 24 h of the two doses of tarafenacin compared with placebo from baseline to 12 weeks after treatment. RESULTS: A total of 334 patients were screened, of whom 235 patients were randomised. The mean decrease in the number of micturitions per 24 h from baseline to 12 weeks was statistically higher in the tarafenacin 0.4 mg group (-2.43 ± 2.21 times per day, p = 0.033) and non-statistically significant in the tarafenacin 0.2 mg group (-1.92 ± 2.45 times per day, p = 0.393) when compared with the placebo group (-1.77 ± 2.95 times per day). There were no statistically significant differences in the mean change of urgency episodes per 24 h among three groups. The most common adverse event was dry mouth. There were no significant differences in blurred vision and constipation compared with placebo. CONCLUSIONS: Tarafenacin 0.4 mg decreased the number of micturitions in patients with OAB after 12 weeks compared with placebo, and the dose-response relationship of tarafenacin 0.2 and 0.4 mg was confirmed. Both dose levels of tarafenacin were well tolerated.


Assuntos
Antagonistas Muscarínicos/uso terapêutico , Receptor Muscarínico M3/efeitos dos fármacos , Bexiga Urinária Hiperativa/tratamento farmacológico , Incontinência Urinária/tratamento farmacológico , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/efeitos adversos , Placebos
11.
Phys Rev Lett ; 111(20): 202301, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24289677

RESUMO

We present results for three charmonia states (ψ', χc, and J/ψ) in d+Au collisions at |y|<0.35 and sqrt[s(NN)]=200 GeV. We find that the modification of the ψ' yield relative to that of the J/ψ scales approximately with charged particle multiplicity at midrapidity across p+A, d+Au, and A+A results from the Super Proton Synchrotron and the Relativistic Heavy Ion Collider. In large-impact-parameter collisions we observe a similar suppression for the ψ' and J/ψ, while in small-impact-parameter collisions the more weakly bound ψ' is more strongly suppressed. Owing to the short time spent traversing the Au nucleus, the larger ψ' suppression in central events is not explained by an increase of the nuclear absorption owing to meson formation time effects.

12.
Phys Rev Lett ; 111(21): 212301, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313481

RESUMO

The PHENIX collaboration at the Relativistic Heavy Ion Collider (RHIC) reports measurements of azimuthal dihadron correlations near midrapidity in d+Au collisions at √(s(NN))=200 GeV. These measurements complement recent analyses by experiments at the Large Hadron Collider (LHC) involving central p+Pb collisions at √(s(NN))=5.02 TeV, which have indicated strong anisotropic long-range correlations in angular distributions of hadron pairs. The origin of these anisotropies is currently unknown. Various competing explanations include parton saturation and hydrodynamic flow. We observe qualitatively similar, but larger, anisotropies in d+Au collisions at RHIC compared to those seen in p+Pb collisions at the LHC. The larger extracted v2 values in d+Au are consistent with expectations from hydrodynamic calculations owing to the larger expected initial-state eccentricity compared with that from p+Pb collisions. When both are divided by an estimate of the initial-state eccentricity the scaled anisotropies follow a common trend with multiplicity that may extend to heavy ion data at RHIC and the LHC, where the anisotropies are widely thought to arise from hydrodynamic flow.

14.
Phys Rev Lett ; 109(24): 242301, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23368311

RESUMO

The PHENIX experiment has measured electrons and positrons at midrapidity from the decays of hadrons containing charm and bottom quarks produced in d+Au and p+p collisions at sqrt[S(NN)]=200 GeV in the transverse-momentum range 0.85 ≤ p(T)(e) ≤ 8.5 GeV/c. In central d+Au collisions, the nuclear modification factor R(dA) at 1.5

15.
Nano Lett ; 11(4): 1591-7, 2011 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-21446734

RESUMO

We report on transport measurement performed on a room-temperature-operating ultrasmall Coulomb blockade devices with a silicon island of sub5 nm. The charge stability at 300K exhibits a substantial change in slopes and diagonal size of each successive Coulomb diamond, but remarkably its main feature persists even at low temperature down to 5.3K except for additional Coulomb peak splitting. This key feature of charge stability with additional fine structures of Coulomb peaks are successfully modeled by including the interplay between Coulomb interaction, valley splitting, and strong quantum confinement, which leads to several low-energy many-body excited states for each dot occupancy. These excited states become enhanced in the sub5 nm ultrasmall scale and persist even at 300K in the form of cluster, leading to the substantial modulation of charge stability.


Assuntos
Modelos Químicos , Nanoestruturas/química , Silício/química , Simulação por Computador , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Teoria Quântica , Eletricidade Estática , Temperatura
16.
Physiol Res ; 71(2): 297-303, 2022 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-35275700

RESUMO

Ketamine, an N-methyl-D-aspartate antagonist, reduces pain by decreasing central sensitization and pain windup. However, chronic ketamine use can cause tolerance, dependency, impaired consciousness, urinary symptoms, and abdominal pain. This study aimed to investigate the effects of repeated ketamine injections and ketamine readministration after discontinuation in a rat model of neuropathic pain. To induce neuropathic pain, partial sciatic nerve ligation (PSNL) was performed in 15 male Wistar rats, and these animals were divided into three groups: PSNL (control), PSNL + ketamine 5 mg/kg (K5), and PSNL + ketamine 10 mg/kg (K10; n=5 each). Ketamine was injected intraperitoneally daily for 4 weeks, discontinued for 2 weeks, and then readministered for 1 week. Following PSNL, the mechanical withdrawal threshold was determined weekly using the Von Frey. The K10 group showed a significant increase in the mechanical withdrawal threshold, presented here as the target force (in g), at 21 and 28 days compared to the time point before ketamine injection (mean±SE, 276.0±24.0 vs. 21.6±2.7 and 300.0±0.0 vs. 21.6±2.7, respectively; P<0.01) and at 14, 21, and 28 days compared to the control group (108.2±51.2 vs. 2.7±1.3, 276.0±24.0 vs. 2.5±1.5, and 300.0±0.0 vs. 4.0±0.0, respectively; P<0.05). However, in the K10 group, the ketamine effects decreased significantly at 7 days after readministration compared to those after 28 days of repeated injections (P<0.05). In the K10 group, repeated ketamine injections showed a significant increase in antinociceptive effect for >2 weeks, but this ketamine effect decreased after drug readministration.


Assuntos
Ketamina , Neuralgia , Animais , Hiperalgesia , Ketamina/farmacologia , Masculino , Neuralgia/tratamento farmacológico , Medição da Dor , Ratos , Ratos Wistar , Nervo Isquiático
17.
Phys Rev Lett ; 106(6): 062001, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21405459

RESUMO

Large parity-violating longitudinal single-spin asymmetries A(L)(e+) = -0.86(-0.14) (+0.30) and A(L)(e-) = 0.88(-0.71) (+0.12) are observed for inclusive high transverse momentum electrons and positrons in polarized p+p collisions at a center-of-mass energy of sqrt[s] = 500 GeV with the PHENIX detector at RHIC. These e± come mainly from the decay of W± and Z0 bosons, and their asymmetries directly demonstrate parity violation in the couplings of the W± to the light quarks. The observed electron and positron yields were used to estimate W± boson production cross sections for the e± channels of σ(pp → W+ X) × BR(W+ → e+ ν(e)) = 144.1 ± 21.2(stat)(-10.3) (+3.4) (syst) ± 21.6(norm) pb, and σ(pp → W- X) × BR(W- → e- ν[over ¯](e)) = 31.7 ± 12.1(stat)(-8.2) (+10.1) (syst) ± 4.8(norm) pb.

18.
Phys Rev Lett ; 107(17): 172301, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22107509

RESUMO

Back-to-back hadron pair yields in d+Au and p+p collisions at √s(NN)=200 GeV were measured with the PHENIX detector at the Relativistic Heavy Ion Collider. Rapidity separated hadron pairs were detected with the trigger hadron at pseudorapidity |η|<0.35 and the associated hadron at forward rapidity (deuteron direction, 3.0<η<3.8). Pairs were also detected with both hadrons measured at forward rapidity; in this case, the yield of back-to-back hadron pairs in d+Au collisions with small impact parameters is observed to be suppressed by a factor of 10 relative to p+p collisions. The kinematics of these pairs is expected to probe partons in the Au nucleus with a low fraction x of the nucleon momenta, where the gluon densities rise sharply. The observed suppression as a function of nuclear thickness, p(T), and η points to cold nuclear matter effects arising at high parton densities.

19.
Diabetologia ; 52(1): 115-24, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18946656

RESUMO

AIMS/HYPOTHESIS: Recent studies have shown that bone marrow transplantation reduces hyperglycaemia in a mouse model of diabetes induced by streptozotocin. However, the essential factors for the improvement of hyperglycaemia by bone marrow transplantation have not been fully elucidated. The aim of this study was to search for such factors. METHODS: We investigated the effect of irradiation to whole body, to abdomen alone or to whole body excluding abdomen, followed by infusion or no infusion of bone marrow cells. We also investigated the effect of bone marrow transplantation on beta cell-specific vascular endothelial growth factor-A gene (Vegfa) knockout mice. RESULTS: Bone marrow transplantation improved streptozotocin-induced hyperglycaemia and partially restored islet mass. This change was associated with increased islet vascularisation. Among the other methods investigated, low-dose irradiation of the whole body without infusion of bone marrow cells also improved blood glucose level. In streptozotocin-treated beta cell-specific Vegfa knockout mice, which exhibit impaired islet vascularisation, bone marrow transplantation neither improved hyperglycaemia, relative beta cell mass nor islet vascularisation. CONCLUSION/INTERPRETATION: Our results indicate that whole body irradiation is essential and sufficient for restoration of beta cell mass after streptozotocin treatment independent of infusion of bone marrow cells. Vascular endothelial growth factor-A produced in beta cells is also essential for this phenomenon.


Assuntos
Transplante de Medula Óssea , Diabetes Mellitus Experimental/cirurgia , Células Secretoras de Insulina/citologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Irradiação Corporal Total , Animais , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Teste de Tolerância a Glucose , Hiperglicemia/prevenção & controle , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante Isogênico
20.
Acta Neurol Scand ; 117(4): 273-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17922892

RESUMO

BACKGROUND: Narcolepsy typically begins between adolescence and early adulthood causing severe neuropsychiatric impairments, but few prevalence studies are available on adolescent narcoleptics. In the present study, we investigated the prevalence of narcolepsy-cataplexy in adolescents. METHODS: In total 20,407 students, aged 14-19 years, participated in this study. Ullanlinna Narcolepsy Scale (UNS) was applied to all subjects and those with a UNS score of > or =14 were contacted by phone for semi-structured interview. Subjects then suspected of having narcolepsy participated in a laboratory investigation, which included polysomnography and HLA typing, or were interviewed in detail by telephone. RESULTS: Three subjects were finally diagnosed as narcolepsy with cataplexy and seven subjects might be diagnosed as narcolepsy without cataplexy. Among three narcoleptics with cataplexy, two subjects were HLA-DQB1*0602 and DRB1*1501 positive, but one subject had no test of HLA typing. The prevalence of narcolepsy with cataplexy in Korean adolescence was thus determined to be 0.015% (95% confidence interval = 0.0-0.0313%). CONCLUSION: This epidemiologic study is the first of its type on adolescent narcolepsy to use the International Classification of Sleep Disorders, 2nd edition (ICSD-2) diagnostic criteria. Considering those cases with an onset after adolescence were not included, the prevalence of narcolepsy with cataplexy determined in the present study is comparable with that of other studies in adults.


Assuntos
Narcolepsia/diagnóstico , Narcolepsia/epidemiologia , Adolescente , Adulto , Idade de Início , Povo Asiático , Diagnóstico Diferencial , Feminino , Genótipo , Antígenos HLA/genética , Humanos , Entrevistas como Assunto , Coreia (Geográfico)/epidemiologia , Masculino , Narcolepsia/fisiopatologia , Polissonografia , Valor Preditivo dos Testes , Prevalência , Inquéritos e Questionários
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