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1.
Phys Rev Lett ; 128(7): 072501, 2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35244436

RESUMEN

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470

2.
Phys Rev Lett ; 126(6): 062501, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33635678

RESUMEN

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21 MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

3.
Phys Rev Lett ; 125(13): 137202, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-33034489

RESUMEN

In the three-dimensional (3D) Heisenberg model, topological point defects known as spin hedgehogs behave as emergent magnetic monopoles, i.e., quantized sources and sinks of gauge fields that couple strongly to conduction electrons, and cause unconventional transport responses such as the gigantic Hall effect. We observe a dramatic change in the Hall effect upon the transformation of a spin hedgehog crystal in a chiral magnet MnGe through combined measurements of magnetotransport and small-angle neutron scattering (SANS). At low temperatures, well-defined SANS peaks and a negative Hall signal are each consistent with expectations for a static hedgehog lattice. In contrast, a positive Hall signal takes over when the hedgehog lattice fluctuates at higher temperatures, with a diffuse SANS signal observed upon decomposition of the hedgehog lattice. Our approach provides a simple way to both distinguish and disentangle the roles of static and dynamic emergent monopoles on the augmented Hall motion of conduction electrons.

4.
Public Health ; 185: 80-86, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32574872

RESUMEN

OBJECTIVES: Family caregiver burden is associated with higher psychological distress. However, little is known about the impact of neighbourhood relationships on caregivers' psychological distress. We examined whether neighbourhood relationships of caregivers moderate the association between family caregiver burden and psychological distress. STUDY DESIGN: This was a cross-sectional study. METHODS: We recruited 5321 Japanese adults who participated in the Japan Multi-Institutional Collaborative Cohort Study in the Okazaki area between 2013 and 2017. Participants completed self-reported questionnaires to measure psychological distress (Kessler 6: K6), subjective caregiver burden, and neighbourhood relationships. We performed a multivariable linear regression analysis in which caregiver burden was designated as an independent variable and the K6 score as a dependent variable, adjusting for demographics. The interaction term between caregiver burden and neighbourhood relationships was also included in the analysis. RESULTS: Data from a total of 5069 participants were included (mean age [standard deviation]: 63.1 years [10.3 years]; 2226 [43.9%] female). Caregiver burden was significantly and positively associated with psychological distress (compared with no burden, mild burden: ß = 0.24, P = 0.197; severe burden: ß = 0.60, P < 0.01; P for trend < 0.01). There was a significant negative interaction effect of caregiver burden × neighbourhood relationship on psychological distress (severe burden × good neighbourhood relationship: ß = -3.29, P < 0.01). CONCLUSIONS: A higher caregiver burden was associated with higher psychological distress, and neighbourhood relationships moderated this association. Our findings suggest that good neighbourhood relationships can buffer caregiving-associated psychological distress.


Asunto(s)
Cuidadores/psicología , Relaciones Interpersonales , Distrés Psicológico , Características de la Residencia , Adaptación Psicológica , Adulto , Anciano , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
5.
Phys Rev Lett ; 118(5): 052701, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28211732

RESUMEN

The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.

6.
Ann Oncol ; 27(5): 887-95, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26884589

RESUMEN

BACKGROUND: Inherited thrombocytopenia (IT) contains several forms of familial thrombocytopenia and some of them have propensity to hematological malignancies. The etiological and genetic features of this heterogeneous syndrome have not yet been elucidated. PATIENTS AND METHODS: We conducted a nationwide survey to collect clinical information and samples from patients with familial thrombocytopenia and/or hematological malignancies in order to obtain a comprehensive understanding of IT. RESULTS: Among the 43 pedigrees with clinical samples, RUNX1 mutations were identified in 8 pedigrees (18.6%). While MYH9 and ANKRD26 mutations were identified in 2 and 1 pedigrees, respectively, no gene mutations were detected in the remaining 32 pedigrees from a panel of previously reported pathogenetic mutations. Clinical data were comparable between FPD/AML and non-FPD/AML probands. CONCLUSIONS: Our study clarified that it is unexpectedly difficult to diagnose FPD/AML based on clinical information alone, and thus, genetic testing is strongly recommended. Our survey also identified some pedigrees with a strong family history of myelodysplastic syndromes of unknown origin. Additionally, there were 14 pedigrees in which three or more members were affected by immune thrombocytopenia (ITP), and a computer-aided simulation suggested that such a distribution almost never happens by coincidence, which implicates a genetic predisposition to ITP.


Asunto(s)
Trastornos de la Coagulación Sanguínea Heredados/epidemiología , Trastornos de las Plaquetas Sanguíneas/epidemiología , Plaquetas/patología , Neoplasias Hematológicas/epidemiología , Leucemia Mieloide Aguda/epidemiología , Trombocitopenia/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Trastornos de la Coagulación Sanguínea Heredados/genética , Trastornos de la Coagulación Sanguínea Heredados/patología , Trastornos de las Plaquetas Sanguíneas/genética , Trastornos de las Plaquetas Sanguíneas/patología , Niño , Preescolar , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Humanos , Lactante , Japón/epidemiología , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Mutación , Trombocitopenia/genética , Trombocitopenia/patología
7.
Phys Chem Chem Phys ; 18(46): 31664-31669, 2016 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-27840865

RESUMEN

In this study, nanoscale hydration dynamics of DNA-lipid blend dry films are investigated via small angle X-ray diffraction. Compared to the hydration of lipid films, fragmented short DNA strands and counterions in stacked lipid layers dramatically accelerate both the relaxation of the lamellar distance to a metastable interval and the subsequent peeling-off process of lipid bilayers. Moreover, genome-sized long DNA and counterions accelerate the relaxation process, but suppress the peeling-off process and simultaneously induce a damped-oscillation of the lamellar interval; this is probably due to the viscoelastic properties of the entangled long DNA dissolved in hydrated water between the stacked lipid bilayers. This study's findings can pave the way for producing cell-sized liposomes, which efficiently encapsulate any arbitrary sized DNA through natural swelling.


Asunto(s)
ADN/química , Membrana Dobles de Lípidos/química , Agua/química , Tamaño de la Partícula , Fosfatidilcolinas/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X
8.
Public Health ; 141: 74-79, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27932019

RESUMEN

OBJECTIVES: Road traffic injuries, particularly pedestrian injuries, are a major health issue among children worldwide. The present study quantitatively analyzed the time trends of child pedestrian injuries in Japan from 1975 to 2013 by age. STUDY DESIGN: Time trend analysis of nationally aggregated data. METHODS: We analyzed police data on pedestrian injuries requiring medical treatment among children aged 0-15 years occurring between 1975 and 2013. To quantify the time trends of pedestrian injury morbidity rates and to identify change-points in the trends, joinpoint regression analysis was applied by age group. Children were categorized into the age groups of 0-3, 4-6, 7-9, 10-12, and 13-15 years old. RESULTS: Preschool children aged 0-6 years old showed continuous declining trends throughout the study period; these declining trends accelerated in the 2000s. School-age children aged 7-15 years old showed minimal changes from the early 1970s to the 1990s; of this age group, children aged 7-12 years old showed slight but significant declining trends in the first half and increasing trends in the latter half of this period. Children aged 7-15 years old showed declining trends in the 2000s. Despite the consistent declining trends among all age groups in the 2000s, the younger age groups showed steeper declines during this period. CONCLUSIONS: The declining trends in all age groups in the 2000s may reflect the improved traffic environments in Japan although the environmental approaches are not yet sufficiently adopted yielding modest effects. The continuing contrast between preschool and school-age children may reflect different behaviour changes by age such as more restricted outdoor activities among young children.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Peatones/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Adolescente , Distribución por Edad , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Japón/epidemiología , Morbilidad/tendencias , Estudios Retrospectivos
9.
Phys Rev Lett ; 110(11): 117202, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25166569

RESUMEN

Magnetotransport properties have been investigated for epitaxial thin films of B20-type MnSi grown on Si(111) substrates. Lorentz transmission electron microscopy images clearly point to the robust formation of Skyrmions over a wide temperature-magnetic field region. New features distinct from those reported previously for MnSi are observed for epitaxial films: a shorter (nearly half) period of the spin helix and Skyrmions, and a topological Hall effect anomaly consisting in ∼2.2 times enhancement of the amplitude and in the opposite sign with respect to bulk samples.

10.
Infection ; 41(1): 219-23, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22971937

RESUMEN

BACKGROUND: There have been no reports of human herpesvirus-6 (HHV-6) encephalitis treatment based on both HHV-6 DNA load and the antiviral agent's concentration in the cerebrospinal fluid (CSF). PATIENT: A 20-year-old male with a hematological malignancy developed HHV-6 encephalitis 15 days after unrelated cord blood transplantation (UCBT). He had fever, chest pain, memory impairment, and insomnia. His CSF showed no increased cell counts, but the amount of HHV-6 DNA was elevated to 2.0 × 10(6) copies/ìgDNA. Magnetic resonance imaging (MRI) of the head revealed abnormal high-intensity signals in the left limbic system on T2-weighted and diffusion-weighted images. Intravenous administration of ganciclovir (GCV) was initiated at 5 mg/kg every 12 h on day 18, and was continued until day 137. The amount of HHV-6 DNA in the plasma became undetectable on day 25. The HHV-6 load in the CSF decreased to 1.5 × 10(3) copies/ìgDNA on day 32, and reached undetectable levels on day 53. The mean concentration of GCV 1 h after an infusion of 5 mg/kg was 4.12 mg/mL in plasma and 0.7 mg/mL in CSF. The chest pain and insomnia disappeared on days 35 and 47, respectively. Memory defects recovered up to day 85. CONCLUSION: Serial quantification of HHV-6 DNA in CSF may be useful for successful treatment with GCV in post-transplant HHV-6 encephalitis.


Asunto(s)
Antivirales/uso terapéutico , Encefalitis Viral/tratamiento farmacológico , Ganciclovir/uso terapéutico , Herpesvirus Humano 6/aislamiento & purificación , Infecciones por Roseolovirus/tratamiento farmacológico , Adulto , Encéfalo/patología , Trasplante de Células Madre de Sangre del Cordón Umbilical/efectos adversos , ADN Viral/líquido cefalorraquídeo , Encefalitis Viral/diagnóstico , Encefalitis Viral/virología , Ganciclovir/farmacocinética , Humanos , Imagen por Resonancia Magnética , Masculino , Infecciones por Roseolovirus/diagnóstico , Infecciones por Roseolovirus/virología , Carga Viral , Adulto Joven
11.
Acta Neurol Scand ; 125(3): 206-12, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21615351

RESUMEN

BACKGROUND: Circadian periodicity in the onset of stroke has been reported. However, it is unclear whether this variation affects the acute stroke case fatality. Time of the day variation in stroke case fatality was examined using population-based stroke registration data. METHODS: Stroke event data were acquired from the Takashima Stroke Registry, which covers a stable population of approximately 55,000 in Takashima County in central Japan. During the period of 1990-2003, there were 1080 (549 men and 531 women) cases with classifiable stroke onset time. Stroke incidence was categorized as occurring at night (midnight-6 a.m.), morning (6 a.m.-noon), afternoon (noon-6 p.m.), and evening (6 p.m.-midnight). The 28-day case fatality rates and 95% confidence intervals (95% CI) were calculated by gender, age, and stroke subtype across the time blocks. After adjusting for gender, age at onset, and stroke severity at onset, the hazard ratios for fatal strokes in evening, night, and morning were calculated, with afternoon serving as the reference. RESULTS: For all strokes, the 28-day case fatality rate was 23.3% (95% CI:19.4-27.6) for morning onset, 16.9% (95% CI:13.1-21.6) for afternoon onset, 18.3% (95% CI:13.6-24.1) for evening onset, and 21.0% (95% CI:15.0-28.5) for the night onset stroke. The case fatality for strokes during the morning was higher than the case fatality for strokes during afternoon. This fatality risk excess for morning strokes persisted even after adjusting for age, gender, and stroke severity on onset in multivariate analysis. CONCLUSION: In the examination of circadian variation of stroke case fatality, 28-day case fatality rate tended to be higher for the morning strokes.


Asunto(s)
Trastornos Cronobiológicos/mortalidad , Accidente Cerebrovascular/mortalidad , Enfermedad Aguda , Anciano , Trastornos Cronobiológicos/fisiopatología , Ritmo Circadiano/fisiología , Comorbilidad , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Sistema de Registros , Medición de Riesgo/métodos , Accidente Cerebrovascular/fisiopatología
12.
Parasite ; 19(1): 85-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22314245

RESUMEN

Fasciola spp. were collected from naturally infected cattle at a local abattoir of Khanh Hoa province, Vietnam, for morphological and genetic investigations. Microscopic examination detected no sperm cells in the seminal vesicles, suggesting a parthenogenetic reproduction of the flukes. Analyses of sequences from the first and second internal transcribed spacers (ITS1 and ITS2) of the ribosomal RNA revealed that 13 out of 16 isolates were of Fasciola gigantica type, whereas three isolates presented a hybrid sequence from F. gigantica and Fasciola hepatica. Interestingly, all the mitochondrial sequences (partial COI and NDI) were of F. gigantica type, suggesting that the maternal lineage of the hybrid form is from F. gigantica. No intra-sequence variation was detected.


Asunto(s)
Enfermedades de los Bovinos/parasitología , ADN de Helmintos/química , Fasciola/aislamiento & purificación , Fascioliasis/veterinaria , Animales , Secuencia de Bases , Bovinos , Enfermedades de los Bovinos/diagnóstico , ADN de Helmintos/aislamiento & purificación , ADN Mitocondrial/química , ADN Mitocondrial/aislamiento & purificación , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/aislamiento & purificación , Fasciola/genética , Fascioliasis/diagnóstico , Fascioliasis/parasitología , Datos de Secuencia Molecular , Alineación de Secuencia , Vietnam
13.
Rev Sci Instrum ; 93(5): 053301, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35649793

RESUMEN

A beam optics study using the ITER-relevant high intense negative ion beams, such as 1 MeV, 200 A/m2, has been performed experimentally and analytically using a multi-aperture and five-stage accelerator. Initially, multi-beamlets generated from this accelerator were deflected in various directions due to the magnetic field and space charge repulsion between beams and showed various divergences. These had limited the pulse length and the beam energy. Compensation methods of the beamlet deflections have worked effectively and contributed to achieving the ITER requirement, the divergence angle of <7 mrad, and the deflection angle of <1 mrad for 1 MeV beam. The beam pulse has been gradually extended from 1 to 100 s and is now going to a longer pulse based on these results. One of the remaining issues is to understand and suppress peripheral components of the beam, namely, the halo, and to reduce the local heat loads observed around the aperture edge. This halo component has been successfully distinguished from the beam core by using a newly developed beam emittance measurement system for high intense beams. By combining this measured beam emittance and the beam simulation, it was clarified for the first time that the halo components are generated in an area of 1 mm width from the aperture edge.

14.
Eur Rev Med Pharmacol Sci ; 26(14): 5154-5163, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35916813

RESUMEN

OBJECTIVE: Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber produced by the controlled partial enzymatic hydrolysis of guar gum beans, has various physiological roles. PHGG is expected to influence the immune function and prevent infections. The objective of this study was to examine the effect of continuous ingestion of PHGG for 12 weeks on the development of cold-like symptoms. PATIENTS AND METHODS: A placebo-controlled, double blind, randomized, parallel-group comparative study was conducted. 96 healthy Japanese adults received 5.2 g PHGG or placebo daily for 12 weeks. Cold-like symptoms were assessed based on patient diary, and the levels of short-chain fatty acids (SCFAs) in stool and blood immune markers at baseline and at weeks 6 and 12. RESULTS: The cumulative number of "no symptoms" days for all symptoms was significantly larger in the PHGG than in the placebo group. The result of the analysis by severity of cold-like symptoms also showed significant differences, with the PHGG group having a lower severity of cold-like symptoms. Propionic acid at weeks 6 and 12 and n-butyric acid and total SCFAs at week 12 were significantly higher in the PHGG than in the placebo group. The Interferon-γ level was significantly lower at week 6 in the PHGG than in the placebo group. CONCLUSIONS: PHGG intake may affect immune function and suppress cold-like symptoms through the production of SCFAs in healthy adults.


Asunto(s)
Galactanos , Gomas de Plantas , Adulto , Fibras de la Dieta , Heces , Humanos , Hidrólisis , Mananos/uso terapéutico , Gomas de Plantas/uso terapéutico
15.
Nat Commun ; 12(1): 5974, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34645795

RESUMEN

Physics of Weyl electrons has been attracting considerable interests and further accelerated by recent discoveries of giant anomalous Hall effect (AHE) and topological Hall effect (THE) in several magnetic systems including non-coplanar magnets with spin chirality or small-size skyrmions. These AHEs/THEs are often attributed to the intense Berry curvature generated around the Weyl nodes accompanied by band anti-crossings, yet the direct experimental evidence still remains elusive. Here, we demonstrate an essential role of the band anti-crossing for the giant AHE and THE in MnGe thin film by using the terahertz magneto-optical spectroscopy. The low-energy resonance structures around ~ 1.2 meV in the optical Hall conductivity show the enhanced AHE and THE, indicating the emergence of at least two distinct anti-crossings near the Fermi level. The theoretical analysis demonstrates that the competition of these resonances with opposite signs is a cause of the strong temperature and magnetic-field dependences of observed DC Hall conductivity. These results lead to the comprehensive understanding of the interplay among the transport phenomena, optical responses and electronic/spin structures.

20.
Rev Sci Instrum ; 91(2): 023506, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32113410

RESUMEN

Long pulse acceleration of hydrogen negative ion beams with the power density over 70 MW/m2 and the pulse length over 100 s has been demonstrated for the first time by using a multi-aperture 3-stage accelerator. Such long pulse acceleration was achieved by integrating the design of beam optics and voltage holding capability to meet the requirements of JT-60SA. By using the newly designed accelerator for JT-60SA, voltage holding at 500 kV with beam acceleration was stably sustained even after 5 g of cesium was seeded, and heat load on each acceleration grid was reduced below the allowable level for long pulse, less than 5% of total acceleration power. As a result, 500 keV, 154 A/m2 for 118 s beam acceleration was achieved, which satisfies the requirement of the negative ion source for JT-60SA. This pulse length of such high-power density beams is longest in the world. In addition, the result contributes to the long pulse acceleration of multi-stage electrostatic accelerators, such as 1 MeV negative ion accelerator for ITER.

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