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1.
Phys Rev Lett ; 130(25): 251901, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37418716

RESUMEN

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

Asunto(s)
Alimentos , Fotones , Movimiento (Física)
2.
Phys Rev Lett ; 128(11): 112503, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35363014

RESUMEN

We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst) eV and 6463.7±0.3(stat)±0.1(syst) eV, and widths to be 2.5±1.0(stat)±0.4(syst) eV and 1.0±0.6(stat)±0.3(stat) eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

3.
Phys Rev Lett ; 127(16): 162001, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34723614

RESUMEN

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.

5.
Phys Rev Lett ; 123(2): 022301, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31386493

RESUMEN

The PHENIX collaboration presents first measurements of low-momentum (0.41 GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5 GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

6.
Phys Rev Lett ; 123(12): 122001, 2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31633981

RESUMEN

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

7.
Phys Rev Lett ; 121(22): 222301, 2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30547634

RESUMEN

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.

8.
Phys Rev Lett ; 120(2): 022001, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29376675

RESUMEN

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.

9.
Phys Rev Lett ; 120(6): 062302, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29481251

RESUMEN

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.

10.
Pharmazie ; 73(5): 309-312, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29724300

RESUMEN

As a result of the RAINBOW trial, ramucirumab plus paclitaxel was established as a second-line treatment of advanced gastric cancer. Regarding the safety of ramucirumab plus paclitaxel in the Japanese, a subgroup analysis of the RAINBOW trial was conducted. The incidence of neutropenia was higher in Japanese patients. However, information is lacking concerning the safety of ramucirumab after marketing in Japanese patients. Therefore, the aim of this study was to evaluate the safety of ramucirumab in Japanese patients with advanced gastric cancer. The inclusion criteria were patients diagnosed with advanced gastric cancer who had commenced treatment with ramucirumab plus paclitaxel or paclitaxel only at Ogaki Municipal Hospital (Gifu, Japan) between January 2015 and December 2016. There were 26 patients in the ramucirumab plus paclitaxel group and 22 patients in the paclitaxel only group. Treatment-related adverse events were documented in 100.0% of the patients in the ramucirumab plus paclitaxel group (Grade 3-4, 73.1%) and 90.9 % of the patients in the paclitaxel only group (Grade 3-4, 45.5 %). The most frequently observed adverse event in both treatment groups was anemia. The second common adverse event was neutropenia. The incidence of neutropenia of Grade ≥3 was significantly higher in the ramucirumab plus paclitaxel group than in the paclitaxel only group. In conclusion, the incidence of neutropenia is high. However, we believe that ramucirumab plus paclitaxel can be safely administered.


Asunto(s)
Anticuerpos Monoclonales/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Pueblo Asiatico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neutropenia/inducido químicamente , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Neoplasias Gástricas/sangre , Ramucirumab
11.
Phys Rev Lett ; 116(12): 122301, 2016 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-27058071

RESUMEN

Jet production rates are measured in p+p and d+Au collisions at sqrt[s_{NN}]=200 GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Jets are reconstructed using the R=0.3 anti-k_{t} algorithm from energy deposits in the electromagnetic calorimeter and charged tracks in multiwire proportional chambers, and the jet transverse momentum (p_{T}) spectra are corrected for the detector response. Spectra are reported for jets with 12

12.
Pharmazie ; 71(4): 218-21, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27209703

RESUMEN

We retrospectively studied the safety of trifluridine/tipiracil combination tablet (TAS-102) monotherapy in patients with advanced and recurrent colorectal cancer. Adverse events to TAS-102 monotherapy were observed in 22 out of 23 cases (95.7%). The most frequent adverse events were neutropenia (69.6%), nausea (53.2%), and malaise (30.4%). Treatment was postponed in 54 (59.3%) out of 91 courses, and in 34 (66.7%) of these 54 courses, the delay in treatment was due to bone marrow suppression. Seven patients with peritoneal metastases suffered from nausea, whilst none of the patients without peritoneal metastases had nausea (p = 0.0139). Nausea and vomiting during a previous chemotherapy cycle was significantly associated with nausea after TAS-102 treatment (p = 0.0007), and the treatment cycles were significantly longer in patients with grade 3 or 4 neutropenia (p = 0.0061). Our results suggest that the incidence of nausea was higher in patients treated with TAS-102. Therefore, it is important to inform patients of the risk of these toxicities and to provide enhanced supportive care. Moreover, we recommend that, for patients with repeated treatment postponement due to neutropenia, the dosage should be fixed based on therapeutic efficacy and prognosis.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trifluridina/uso terapéutico , Uracilo/análogos & derivados , Adulto , Anciano , Médula Ósea/efectos de los fármacos , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Náusea/epidemiología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neutropenia/inducido químicamente , Neutropenia/epidemiología , Seguridad del Paciente , Pirrolidinas , Estudios Retrospectivos , Comprimidos , Timina , Uracilo/uso terapéutico , Vómitos/inducido químicamente , Vómitos/epidemiología
13.
Phys Rev Lett ; 115(14): 142301, 2015 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-26551807

RESUMEN

We present the first measurement of elliptic (v(2)) and triangular (v(3)) flow in high-multiplicity (3)He+Au collisions at √(s(NN))=200 GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in (3)He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the (3)He+Au system. The collective behavior is quantified in terms of elliptic v(2) and triangular v(3) anisotropy coefficients measured with respect to their corresponding event planes. The v(2) values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three (3)He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

14.
Phys Rev Lett ; 111(3): 032301, 2013 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-23909311

RESUMEN

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at √[s(NN)]=200 GeV. The p(T) of the photon is an excellent approximation to the initial p(T) of the jet and the ratio z(T)=p(T)(h)/p(T)(γ) is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I(AA), the ratio of hadron yield opposite the photon in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z(T). The associated hadron yield at low z(T) is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

16.
Clin Exp Dermatol ; 37(8): 904-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23050556

RESUMEN

BACKGROUND: High-performance sunscreen protects both healthy consumers and photosensitive patients from strong ultraviolet (UV) exposure. The sun-protection factor (SPF), which indicates the efficacy of UV protection, is determined using a prescribed sunscreen application thickness of 2.0 mg/cm(2). Therefore, users should apply at least 2.0 mg/cm(2) of sunscreen to obtain the level of UV protection expected from a product. In most cases, however, users apply insufficient amounts of sunscreen. AIM: To determine the amount of sunscreen applied under specific conditions, and the relationship between application thickness and SPF value in high-performance sunscreen. METHODS: The amount of applied sunscreen was calculated under practical conditions and conditions that directed a double application. The SPF values of high-performance sunscreen applied at three thicknesses (2.0, 1.0 and 0.5 mg/cm(2)) were determined according to the international SPF testing method. RESULTS. The relationship between SPF value and application thickness correlated in a logarithmic curve. The mean application thickness under practical conditions was approximately 1 mg/cm(2), and directing subjects to use a double application increased the application thickness to nearly 2 mg/cm(2). CONCLUSION: Encouraging a double application of sunscreen will help users apply products at a thickness sufficient to achieve expected SPF efficacy. We recommend that guidance on double application of sunscreen should be posted in public locations where sunscreen is likely to be in use.


Asunto(s)
Piel/efectos de la radiación , Factor de Protección Solar , Quemadura Solar/prevención & control , Protectores Solares/administración & dosificación , Adulto , Pueblo Asiatico , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad
17.
Diabetologia ; 53(2): 234-46, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19727657

RESUMEN

AIMS/HYPOTHESIS: Resistin is a cytokine derived from adipose tissue and is implicated in obesity-related insulin resistance and type 2 diabetes mellitus. Polymorphisms of the resistin gene (RETN) have been shown to affect the plasma resistin concentration. The aims of this study were to identify polymorphisms of RETN that influence plasma resistin concentration and to clarify the relation between plasma resistin level and metabolic disorders in an aged Japanese cohort. METHODS: The study participants comprised 3133 individuals recruited to a population-based prospective cohort study (KING study). Plasma resistin concentration, BMI, abdominal circumference, blood pressure, fasting plasma glucose and serum insulin concentrations, HbA(1c) content and serum lipid profile were measured in all participants. The HOMA index of insulin resistance (HOMA-IR) was also calculated. Eleven polymorphisms of RETN were genotyped. RESULTS: A combination of ANOVA and multiple linear regression analysis in screening and large-scale subsets of the study population revealed that plasma resistin concentration was significantly associated with rs34861192 and rs3745368 polymorphisms of RETN. Multiple linear regression analysis with adjustment for age and sex also showed that the plasma resistin level was significantly associated with serum concentrations of HDL-cholesterol, triacylglycerol and insulin, as well as with BMI. CONCLUSIONS/INTERPRETATION: Our results implicate the rs34861192 and rs3745368 polymorphisms of RETN as robust and independent determinants of plasma resistin concentration in the study population. In addition, plasma resistin level was associated with dyslipidaemia, serum insulin concentration and obesity. TRIAL REGISTRATION: ClinicalTrials.gov NCT00262691.


Asunto(s)
Variación Genética , Enfermedades Metabólicas/sangre , Resistina/sangre , Resistina/genética , Anciano , Análisis de Varianza , Glucemia/metabolismo , Presión Sanguínea , Índice de Masa Corporal , Tamaño Corporal , Estudios de Cohortes , Diabetes Mellitus Tipo 2/genética , Femenino , Genotipo , Hemoglobina Glucada/metabolismo , Humanos , Japón , Lípidos/sangre , Masculino , Enfermedades Metabólicas/genética , Persona de Mediana Edad , Análisis de Regresión
18.
J Phys Condens Matter ; 31(44): 445804, 2019 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-31392970

RESUMEN

We report a combined study of imaging the antiferromagnetic (AFM) spin structure and measuring the spin Hall magnetoresistance (SMR) in epitaxial thin films of the insulating non-collinear antiferromagnet SmFeO3. X-ray magnetic linear dichroism photoemission electron microscopy measurements reveal that the AFM spins of the SmFeO3(1 1 0) align in the plane of the film. Angularly dependent magnetoresistance measurements show that SmFeO3/Ta bilayers exhibit a positive SMR, in contrast to the negative SMR expected in previously studied collinear AFMs. The SMR amplitude increases linearly with increasing external magnetic field at higher magnetic fields, suggesting that field-induced canting of the AFM spins plays an important role. In contrast, around the coercive field, no detectable SMR signal is observed, indicating that the SMR of the AFM and canting magnetization components cancel out. Below 50 K, the SMR amplitude increases sizably by a factor of two as compared to room temperature, which likely correlates with the long-range ordering of the Sm ions. Our results show that the SMR is a sensitive technique for non-equilibrium spin systems of non-collinear AFMs.

19.
Oncogene ; 26(12): 1802-10, 2007 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16964281

RESUMEN

It was reported that short interfering RNA (siRNA) of EWS/Fli-1 downregulated phospholipase D (PLD)2 in Ewing's sarcoma (EWS) cell line, suggesting that PLD2 is the target of aberrant transcription factor, EWS/Fli-1. Here, we further investigated the regulation of PLD2 gene expression by EWS/Fli-1 and Fli-1 in another EWS cell line, and also in EWS/Fli-1- or Fli-1-transfected cell line. EWS/Fli-1- or Fli-1-overexpressed cells showed higher PLD2 but not PLD1 protein expression and enhanced cell proliferation as compared to mock transfectant. The treatment of these cells with 1-butanol or siRNA of PLD2 inhibited cell growth, suggesting the pivotal role of PLD in cell growth promotion. PLD2 but not PLD1 mRNA level was also increased in EWS/Fli-1 or Fli-1-transfectants. After determining the transcription initiation points, we cloned the 5' promoter of both PLD1 and PLD2 and analysed promoter activities. Results showed that EWS/Fli-1 and Fli-1 increase PLD2 gene expression by binding to an erythroblast transformation-specific domain (-126 to -120 bp from the transcription initiation site) of PLD2 promoter, which is the minimal and most powerful region. Electrophoresis mobility shift assay using truncated proteins showed that both DNA-binding domain and trans-activating domain were necessary for the enhanced gene expression of PLD2.


Asunto(s)
Proteínas de Microfilamentos/fisiología , Proteínas de Fusión Oncogénica/fisiología , Fosfolipasa D/genética , Regiones Promotoras Genéticas , Proteína Proto-Oncogénica c-fli-1/fisiología , Receptores Citoplasmáticos y Nucleares/fisiología , Secuencia de Bases , Línea Celular , Cartilla de ADN , Ensayo de Cambio de Movilidad Electroforética , Humanos , Inmunoprecipitación , Proteínas de Microfilamentos/metabolismo , Proteínas de Fusión Oncogénica/metabolismo , Unión Proteica , Proteína Proto-Oncogénica c-fli-1/metabolismo , Proteína EWS de Unión a ARN , Receptores Citoplasmáticos y Nucleares/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transactivadores , Transfección
20.
Neuroscience ; 155(3): 780-8, 2008 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-18640244

RESUMEN

During development of the mammalian CNS, neurons and glial cells (astrocytes and oligodendrocytes) are generated from common neural precursor cells (NPCs). However, neurogenesis precedes gliogenesis, which normally commences at later stages of fetal telencephalic development. Astrocyte differentiation of mouse NPCs at embryonic day (E) 14.5 (relatively late gestation) is induced by activation of the transcription factor signal transducer and activator of transcription (STAT) 3, whereas at E11.5 (mid-gestation) NPCs do not differentiate into astrocytes even when stimulated by STAT3-activating cytokines such as leukemia inhibitory factor (LIF). This can be explained in part by the fact that astrocyte-specific gene promoters are highly methylated in NPCs at E11.5, but other mechanisms are also likely to play a role. We therefore sought to identify genes involved in the inhibition of astrocyte differentiation of NPCs at midgestation. We first examined gene expression profiles in E11.5 and E14.5 NPCs, using Affymetrix GeneChip analysis, applying the Percellome method to normalize gene expression level. We then conducted in situ hybridization analysis for selected genes found to be highly expressed in NPCs at midgestation. Among these genes, we found that N-myc and high mobility group AT-hook 2 (Hmga2) were highly expressed in the E11.5 but not the E14.5 ventricular zone of mouse brain, where NPCs reside. Transduction of N-myc and Hmga2 by retroviruses into E14.5 NPCs, which normally differentiate into astrocytes in response to LIF, resulted in suppression of astrocyte differentiation. However, sustained expression of N-myc and Hmga2 in E11.5 NPCs failed to maintain the hypermethylated status of an astrocyte-specific gene promoter. Taken together, our data suggest that astrocyte differentiation of NPCs is regulated not only by DNA methylation but also by genes whose expression is controlled spatio-temporally during brain development.


Asunto(s)
Astrocitos/fisiología , Diferenciación Celular/genética , Neuronas/fisiología , Células Madre/fisiología , Transcripción Genética/fisiología , Animales , Astrocitos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Embrión de Mamíferos , Femenino , Perfilación de la Expresión Génica/métodos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Factor Inhibidor de Leucemia/farmacología , Ratones , Ratones Endogámicos ICR , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Embarazo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción Genética/métodos
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