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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.

3.
BJOG ; 128(2): 329-335, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298518

RESUMO

OBJECTIVE: Fetal fractional limb volume has been proposed as a useful measure for quantifying fetal soft tissue development. The aim of this study was to investigate the growth of fractional arm volume (AVol) and fractional thigh volume (TVol) of fetuses with maternal gestational diabetes (GDM) compared with those of fetuses with normal glucose tolerance (NGT). We hypothesised fetal fractional limb volume would be larger in the GDM group than in the NGT group in late gestation. DESIGN: Exploratory observational study. SETTING: Saitama Municipal Hospital. SAMPLE: A total of 165 (125 NGT and 40 GDM) singleton Japanese pregnant women. METHODS: AVol and TVol were assessed between 20 and 37 weeks' gestation as cylindrical limb volumes based on 50% of the fetal humeral or femoral diaphysis length. Women were diagnosed as GDM based on the criteria of the Japan Society of Obstetrics and Gynecology. MAIN OUTCOME MEASURES: AVol and TVol were compared between women with NGT and those with GDM at each gestational age period (2-week intervals from 20 to 37 weeks' gestation). RESULTS: Overall, 287 ultrasound scans were performed (NGT group, 205 scans; GDM group, 82 scans). There was no significant difference of AVol between the groups before 32 weeks' gestation. AVol was significantly larger in the GDM group than in the NGT group after 32 weeks' gestation (P < 0.05). TVol was not statistically different between the groups across gestation. CONCLUSIONS: Detection of variations in fetal AVol may provide greater insight into understanding the origins of altered fetal body proportion in GDM. TWEETABLE ABSTRACT: AVol, but not TVol, is significantly larger in fetuses with GDM than in those with NGT after 32 weeks' gestation.


Assuntos
Braço/embriologia , Diabetes Gestacional/diagnóstico por imagem , Desenvolvimento Fetal/fisiologia , Feto/diagnóstico por imagem , Coxa da Perna/embriologia , Adulto , Braço/diagnóstico por imagem , Diáfises/diagnóstico por imagem , Diáfises/embriologia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/embriologia , Idade Gestacional , Humanos , Úmero/diagnóstico por imagem , Úmero/embriologia , Japão , Tamanho do Órgão , Gravidez , Coxa da Perna/diagnóstico por imagem , Ultrassonografia Pré-Natal
5.
Phys Rev Lett ; 124(13): 131301, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302154

RESUMO

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

6.
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

7.
Phys Rev Lett ; 123(2): 022301, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386493

RESUMO

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.

9.
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.

10.
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.

12.
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.

13.
Artigo em Inglês | MEDLINE | ID: mdl-28714277

RESUMO

BACKGROUND: Short-chain fatty acids (SCFA) are microbial fermentation products absorbed by the colon. We recently reported that activation of the SCFA receptor termed free fatty acid receptor 3 (FFA3), expressed on cholinergic nerves, suppresses nicotinic acetylcholine receptor (nAChR)-mediated transepithelial anion secretion. This study aimed to clarify how activation of neurally expressed FFA3 affects colonic motor function. METHODS: FFA3-expressing myenteric neurons were identified by immunostaining; contractions of isolated circular muscle strips obtained from rat proximal colon were measured by isometric transducers. The effect of FFA3 agonists on defecation in vivo was examined in an exogenous serotonin-induced defecation model. KEY RESULTS: FFA3 immunoreactivity was located in nitrergic and cholinergic neurons in the myenteric plexus. In isolated circular muscle strips without mucosa and submucosa, the addition of nicotine (10 µM) or serotonin transiently relaxed the muscle through nitrergic neurons, whereas high concentrations of nicotine (100 µM) induced large-amplitude contractions that were mediated by cholinergic neurons. Pretreatment with FFA3 agonists inhibited nicotine- or serotonin-induced motility changes but had no effect on bethanechol-induced direct muscle contractions. The Gi/o inhibitor pertussis toxin reversed the inhibitory effect of an FFA3 agonist AR420626 on nicotine-evoked contractions, suggesting that FFA3 activation suppresses nAChR-mediated neural activity in myenteric neurons, consistent with an FFA3-mediated antisecretory effect. In conscious rats, exogenous serotonin increased the volume of fecal output, compared with the vehicle- or AR420626-treated groups. Pretreatment with AR420626 significantly suppressed serotonin-induced fecal output. CONCLUSION AND INFERENCES: FFA3 is a promising target for the treatment of neurogenic diarrheal disorders by suppressing nAChR-mediated neural pathways.


Assuntos
Colo/fisiologia , Motilidade Gastrointestinal , Neurônios/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Animais , Neurônios Colinérgicos/metabolismo , Colo/metabolismo , Defecação , Masculino , Contração Muscular , Plexo Mientérico/fisiologia , Neurônios/metabolismo , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Neurônios Nitrérgicos/metabolismo , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Serotonina/administração & dosagem , Antagonistas da Serotonina/administração & dosagem
14.
BJOG ; 124(11): 1729-1735, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28418597

RESUMO

OBJECTIVE: To investigate the association between mid-trimester residual cervical length (CL) and the risk of preterm birth in pregnancies after abdominal radical trachelectomy (RT). DESIGN: Retrospective cohort study. SETTING: University hospital. POPULATION: A total of 33 deliveries after 22 weeks' gestation in 30 women who underwent abdominal RT including prophylactic cervical cerclage and perinatal care between January 2002 and May 2016. METHODS: The association between mid-trimester residual CL (the distance between the cerclage and the external cervical os) and gestational age at delivery was investigated. Receiver-operating characteristics (ROC) curve analysis was performed to estimate the optimal cut-off values of the mid-trimester residual CL for the prediction of preterm birth. MAIN OUTCOME MEASURES: Preterm birth before 34 weeks' gestation. RESULTS: Mid-trimester residual CL showed a significant correlation with gestational age at delivery (r = 0.36, P < 0.05). There was a significant difference in residual CL between women who did and those who did not give birth before 34 weeks (P < 0.05). Mid-trimester residual CL < 13 mm was a good predictor of birth before 34 weeks, with a sensitivity of 67%, specificity of 75%, positive predictive value of 55% and negative predictive value of 86% (area under ROC curve, 0.75). CONCLUSIONS: Mid-trimester residual CL is significantly correlated with gestational age at delivery. Residual CL assessment could be used to reassure physicians and women that there is only a small chance of preterm birth in pregnancies after abdominal RT. TWEETABLE ABSTRACT: Mid-trimester residual cervical length is a good predictor of preterm birth after radical trachelectomy.


Assuntos
Cerclagem Cervical/métodos , Colo do Útero/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/cirurgia , Nascimento Prematuro , Traquelectomia/métodos , Neoplasias do Colo do Útero/cirurgia , Adulto , Medida do Comprimento Cervical/métodos , Feminino , Humanos , Recém-Nascido , Japão , Valor Preditivo dos Testes , Gravidez , Complicações Neoplásicas na Gravidez/epidemiologia , Segundo Trimestre da Gravidez , Curva ROC , Estudos Retrospectivos , Traquelectomia/efeitos adversos , Resultado do Tratamento , Ultrassonografia Pré-Natal , Neoplasias do Colo do Útero/epidemiologia
15.
J Periodontal Res ; 52(4): 686-694, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28177531

RESUMO

BACKGROUND/OBJECTIVES: The periodontal ligament (PDL) is a non-mineralized connective tissue that exists between the alveolar bone and root surface cementum and plays important roles in tooth function. The PDL harbors a remarkable reserve of multipotent stem cells, which maintain various types of cells. However, the sources of these stem cells, other than their developmental origin, are not well understood. MATERIAL AND METHODS: To elucidate the recruitment of bone marrow (BM)-derived stem cells in the PDL, green fluorescent protein (GFP)-expressing BM-derived cells were transplanted into the femoral BM of immunodeficient rats, and the distribution and expression of stem cell markers in the PDL were analyzed in vivo. To evaluate the functional significance of BM-derived cells to the PDL, tooth replantation was performed and the expression of stromal cell-derived factor (SDF)-1, a critical chemotactic signal for mesenchymal stem cell recruitment, was analyzed. To confirm the SDF-1-dependency of BM-derived cell migration to the PDL, PDL-conditioned medium (CM) was prepared, and BM-derived cell migration was analyzed using a transwell culture system. RESULTS: Four weeks after cell transplantation, GFP-positive cells were detected in the PDL, and some of them were also positive for stem cell markers (i.e., CD29, SSEA4, and αSMA). Seven days after tooth replantation, the number of GFP- and SDF-1-positive cells significantly increased in PDL. Concurrently, the concentration of SDF-1 and the number of colony-forming units of fibroblasts in peripheral blood were increased. BM-derived cell migration increased in PDL-CM and was inhibited by an inhibitor of C-X-C chemokine receptor type 4 (CXCR4), an SDF-1 receptor. CONCLUSION: These results indicate that stem cells and their progeny in PDL are not only derived from their developmental origin but are also supplied from the BM via the blood as the need arises. Moreover, this BM-derived cell recruitment appears to be regulated, at least partially, by the SDF-1/CXCR4 axis.


Assuntos
Células da Medula Óssea/citologia , Quimiocina CXCL12/metabolismo , Ligamento Periodontal/citologia , Receptores CXCR4/metabolismo , Animais , Movimento Celular , Células Cultivadas , Imuno-Histoquímica , Masculino , Ratos , Ratos Endogâmicos F344
16.
Phys Rev Lett ; 116(12): 122301, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-27058071

RESUMO

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

18.
Phys Rev Lett ; 115(14): 142301, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26551807

RESUMO

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.

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