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1.
J Phys Condens Matter ; 35(23)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36893472

RESUMEN

Inelastic x-ray scattering measurements have been carried out to investigate atomic dynamics in a melt of fast phase change material GeCu2Te3. The dynamic structure factor was analysed using the model function with three damped harmonic oscillator components. By investigating the correlation between the excitation energy and the linewidth, and that between the excitation energy and the intensity on contour maps of a relative approximate probability distribution function proportional toexp(-χ2/N), we could judge the reliability of each inelastic excitation in the dynamic structure factor. The results indicate that there are two inelastic excitation modes besides the longitudinal acoustic one in the liquid. The lower energy excitation could be assigned to the transverse acoustic one whereas the higher energy one disperses like fast sound. The latter result may imply that the liquid ternary alloy exhibits a microscopic phase separation tendency.

2.
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

4.
J Phys Condens Matter ; 33(47)2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34438373

RESUMEN

The dynamic structure factorS(Q,E), whereQandEare momentum and energy transfer, respectively, has been measured for liquid Sb, using inelastic x-ray scattering. A modified damped harmonic oscillator model function was applied to analyseS(Q,E) of liquid Sb and also to that of liquid Bi by Inuiet al(2015Phys. Rev.B92, 054206). The obtained excitation energy was in fairly good agreement with that predicted byab initiomolecular dynamics simulations on these liquid semi-metals. The excitation energy of the longitudinal acoustic mode in liquid Sb and liquid Bi exhibits flat-toppedQdependence whereas the lower excitation energy below the longitudinal acoustic excitation showsQ-gap behaviour. From the viscosity estimated from theQ-gap experimentally obtained, it is inferred that the lower energy excitation arises from the transverse acoustic excitation in the liquids.

5.
BJOG ; 128(12): 1997-2002, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34021948

RESUMEN

We describe a successful surgical technique of abdominal trachelectomy and re-vaginoplasty for cervico-vaginal stenosis following unsuccessful uterovaginal anastomosis and vaginoplasty in a patient with congenital cervical and vaginal aplasia. After the surgical procedure, cervico-vaginal stenosis was resolved and periodic menstruation without dysmenorrhoea resumed. While long-term follow-up is essential to ensure successful pregnancy and delivery, we conclude that this novel surgical procedure is a promising alternative for improvement of the quality of life and normal sexual function, and for preservation of fertility in patients with cervical and vaginal aplasia.


Asunto(s)
Procedimientos de Cirugía Plástica/métodos , Complicaciones Posoperatorias/cirugía , Traquelectomía/métodos , Vagina/cirugía , Enfermedades Vaginales/cirugía , Adolescente , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Cuello del Útero/anomalías , Cuello del Útero/patología , Constricción Patológica/cirugía , Femenino , Humanos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/patología , Embarazo , Reoperación , Vagina/anomalías , Vagina/patología , Enfermedades Vaginales/etiología , Enfermedades Vaginales/patología
7.
J Phys Condens Matter ; 32(27): 274001, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32143205

RESUMEN

We have developed a special technique and succeeded to carry out small-angle x-ray scattering measurements for some liquid metal systems. The purpose is to investigate effects of transitions such as liquid-liquid (LLT), liquid-gas (LGT) and metal-nonmetal (MNMT) transitions on mesoscopic density fluctuations in liquids. In liquid Te systems (Se-Te and Ge-Te mixtures), which show continuous LLT accompanying MNMT, parameters of density fluctuations show maxima almost in the middle of the transition, both in strength and spatial size. This work (and Kajihara et al 2012 Phys. Rev. B86 214202) was the first direct observation that density fluctuations exhibit maximum corresponding to LLT. However in this study, we could not clearly separate the effects of LLT and MNMT on the observed density fluctuations. Thus, we also investigated fluid Hg under high pressure and high temperature conditions, which shows MNMT near a critical point of LGT, to investigate how MNMT affects them. We observed distinct density fluctuations; a strength and a correlation length of them show maxima at around a critical isochore of LGT, and the former is basically consistent with a phase diagram (compressibility) of LGT; they do not show any peaks at MNMT region. Precise analysis revealed that MNMT only affects a shift of another parameter, a short-range correlation length. These results in fluid Hg indicate that the density fluctuations are mainly derived from a critical phenomena of LGT and MNMT does not play any critical role on them. We believe that the latter conclusion also holds true for liquid Te systems; MNMT plays no important role on the density fluctuations in liquid Te systems and LLT is the main origin of them.

8.
J Phys Condens Matter ; 32(21): 214003, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-31958784

RESUMEN

Inelastic x-ray scattering (IXS) measurements were carried out on liquid Se50Te50 at temperatures up to 1323 K to investigate how the atomic dynamics changes with temperature through the semiconductor-metal transition. The acoustic mode was clearly observed in the dynamic structure factor and its energy was determined using a damped harmonic oscillator model. The dynamical sound speed obtained by IXS for [Formula: see text] nm-1 was found to behave similarly to the temperature dependence of ultrasonic sound velocity with a minimum near the semiconductor metal transition. The results can be explained by taking liquid Se50Te50 to be an inhomogeneous liquid consisting of metallic and semiconducting domains whose size is approximately 3 nm. The relaxation time obtained from frequency dependence of the dynamical sound speed was on a picosecond time scale.

10.
Tech Coloproctol ; 23(10): 973-980, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31535238

RESUMEN

BACKGROUND: Anastomotic leakage (AL) is one of the most troublesome complications in colorectal surgery. Recently, near-infrared fluorescence (NIRF) imaging has been used intraoperatively to detect sentinel lymph nodes and visualize the blood supply at the region of interest (ROI). The aim of this study was to evaluate the role of visualization and quantification of bowel perfusion around the anastomosis using NIRF system in predicting AL. METHODS: A prospective study was conducted on patients who had laparoscopic surgery for colorectal cancer at our institution. Perfusion of the anastomosis was evaluated with NIRF imaging after intravenous injection of indocyanine green (ICG). The time course of fluorescence intensity was recorded by an imaging analyzer We measured the time from ICG injection to the beginning of fluorescence (T0), maximum intensity (Imax), time to reach Imax (Tmax), time to reach Imax 50% ([Formula: see text]) and slope (S) after the anastomosis. RESULTS: Tumor locations were as follows; cecum: 2, ascending colon: 2, transverse colon: 7, descending colon: 1, sigmoid colon: 2, rectosigmoid colon: 3 and rectum: 6 (one case with synchronous cancer). All operations were performed laparoscopically. Four patients were diagnosed with or suspected to have AL (2 patients with grade B anastomotic leakage after low anterior resection, 1 patient with minor leakage in transverse colon resection and 1 patient needing re-anastomosis intraoperatively in transverse colon resection). T0 was significantly longer in the AL group than in patients without AL (64.3 ± 27.6 and 18.2 ± 6.6 s, p = 2.2 × 10-3). CONCLUSIONS: Perfusion of the anastomosis could be successfully visualized and quantified using NIRF imaging with ICG. T0 might be a useful parameter for prediction of AL.


Asunto(s)
Fuga Anastomótica/diagnóstico por imagen , Neoplasias Colorrectales/cirugía , Cuidados Intraoperatorios/métodos , Imagen de Perfusión/métodos , Estomas Quirúrgicos/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Fuga Anastomótica/etiología , Colectomía/efectos adversos , Colectomía/métodos , Colon/irrigación sanguínea , Colon/diagnóstico por imagen , Colon/cirugía , Colorantes , Femenino , Fluorescencia , Humanos , Verde de Indocianina , Rayos Infrarrojos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recto/irrigación sanguínea , Recto/diagnóstico por imagen , Recto/cirugía , Estomas Quirúrgicos/efectos adversos
12.
J Dev Orig Health Dis ; 10(6): 636-644, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30898179

RESUMEN

Recent work has implicated one type of horizontal strabismus (exotropia) as a risk factor for schizophrenia. This new insight raises questions about a potential common developmental origin of the two diseases. Seasonality of births is well established for schizophrenia. Seasonal factors such as light exposure affect eye growth and can cause vision abnormalities, but little is known about seasonality of births in strabismus. We examined birth seasonality in people with horizontal strabismus in a retrospective study in Washoe County, Nevada, and re-examined similar previously obtained data from Osaka, Japan. We then compared seasonal patterns of births between strabismus, refractive error, schizophrenia and congenital toxoplasmosis. Patients with esotropia had a significant seasonality of births, with a deficit in March, then increasing to an excess in September, while patients with exotropia had a distinctly different pattern, with an excess of births in July, gradually decreasing to a deficit in November. These seasonalities were statistically significant with either χ2 or Kolmogorov-Smirnov-type statistics. The birth seasonality of esotropia resembled that for hyperopia, with an increase in amplitude, while the seasonality for myopia involved a phase-shift. There was no correlation between seasonality of births between strabismus and congenital toxoplasmosis. The pattern of an excess of summer births for people with exotropia was remarkably similar to the well-established birth seasonality of one schizophrenia subtype, the deficit syndrome, but not schizophrenia as a whole. This suggests a testable hypothesis: that exotropia may be a risk factor primarily for the deficit type of schizophrenia.


Asunto(s)
Esotropía/complicaciones , Exotropía/complicaciones , Esquizofrenia/etiología , Estaciones del Año , Trastornos de la Visión/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Japón/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esquizofrenia/diagnóstico , Esquizofrenia/epidemiología , Adulto Joven
14.
J Phys Condens Matter ; 30(45): 455101, 2018 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-30251705

RESUMEN

X-ray diffraction and inelastic x-ray scattering measurements of liquid Ba8Ga16Sn30 have been carried out to investigate local structure and atomic dynamics in the liquid. The pair distribution function shows shorter and longer interatomic distances in the first coordination shell. The dynamic structure factor exhibits the inelastic excitations on both sides of the quasielastic central peak. The inelastic excitations disperse with increasing the momentum transfer, suggesting the longitudinal acoustic mode. We found a low energy excitation in addition to the longitudinal acoustic excitation in the dynamic structure factor and it reminds us a strong relationship with a rattling motion of a guest (Ba) atom in the solid state. The temperature dependence of the pair distribution function and the longitudinal acoustic excitation energy is very weak in a range from 600 to 900 °C. The result suggests that Ba and other atoms in the melt are located around minimum positions of the effective pair potential approximated as a harmonic one.

15.
Appl Opt ; 57(17): 4795-4801, 2018 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30118100

RESUMEN

We propose a differential interference contrast method for cells using hard x-ray Gabor holography and knife-edge filtering in the spatial frequency domain, without relying on beam shearing. A phase object is holographically recorded and reconstructed by computer. Interference between the wavefronts of zeroth order weighted by ejπ/2 in the positive frequency region produces a dark image. Similarly, interference between the wavefronts of the zeroth order weighted by ej3π/2 in the negative frequency region produces a bright image. By adding these two intensity distributions, good quality phase-contrast images of 8-µm-diameter polystyrene beads and human HeLa cells were obtained.


Asunto(s)
Holografía/métodos , Interpretación de Imagen Asistida por Computador/métodos , Microscopía de Contraste de Fase/métodos , Microesferas , Células HeLa/patología , Humanos , Poliestirenos , Rayos X
16.
J Phys Condens Matter ; 30(28): 28LT02, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-29873306

RESUMEN

We investigate the dynamic structure factor of the melt of the well known glass former, As2Se3, using inelastic x-ray scattering for temperatures, T, [Formula: see text] K and momentum transfers Q from [Formula: see text] nm-1. An anomaly was observed at Q = 2.7 nm-1 ([Formula: see text] K) with, in the context of a simple model, both an abrupt change in frequency and an increased linewidth reminiscent of an anti-crossing in a solid. Comparison with structural information from reverse Monte Carlo modeling of x-ray diffraction data allows us to associate the disappearance of the anomaly at higher temperatures with a drop in the number of mechanical constraints per atom, n mc, to [Formula: see text] reminiscent of the threshold applicable for glass formation in rigidity theory. It is inferred that the surprising jump in the dispersion in the liquid may be correlated with a stiffness transition in a network glass.

18.
Mol Psychiatry ; 23(3): 639-647, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28115744

RESUMEN

Genome-wide association studies (GWASs) have identified several susceptibility loci for bipolar disorder (BD) and shown that the genetic architecture of BD can be explained by polygenicity, with numerous variants contributing to BD. In the present GWAS (Phase I/II), which included 2964 BD and 61 887 control subjects from the Japanese population, we detected a novel susceptibility locus at 11q12.2 (rs28456, P=6.4 × 10-9), a region known to contain regulatory genes for plasma lipid levels (FADS1/2/3). A subsequent meta-analysis of Phase I/II and the Psychiatric GWAS Consortium for BD (PGC-BD) identified another novel BD gene, NFIX (Pbest=5.8 × 10-10), and supported three regions previously implicated in BD susceptibility: MAD1L1 (Pbest=1.9 × 10-9), TRANK1 (Pbest=2.1 × 10-9) and ODZ4 (Pbest=3.3 × 10-9). Polygenicity of BD within Japanese and trans-European-Japanese populations was assessed with risk profile score analysis. We detected higher scores in BD cases both within (Phase I/II) and across populations (Phase I/II and PGC-BD). These were defined by (1) Phase II as discovery and Phase I as target, or vice versa (for 'within Japanese comparisons', Pbest~10-29, R2~2%), and (2) European PGC-BD as discovery and Japanese BD (Phase I/II) as target (for 'trans-European-Japanese comparison,' Pbest~10-13, R2~0.27%). This 'trans population' effect was supported by estimation of the genetic correlation using the effect size based on each population (liability estimates~0.7). These results indicate that (1) two novel and three previously implicated loci are significantly associated with BD and that (2) BD 'risk' effect are shared between Japanese and European populations.


Asunto(s)
Trastorno Bipolar/genética , Adulto , Proteínas de Ciclo Celular/genética , Citocinas/genética , delta-5 Desaturasa de Ácido Graso , Ácido Graso Desaturasas/genética , Femenino , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Humanos , Japón/epidemiología , Masculino , Glicoproteínas de Membrana/genética , Persona de Mediana Edad , Herencia Multifactorial/genética , Factores de Transcripción NFI/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleótido Simple/genética
19.
Phys Rev Lett ; 118(26): 262501, 2017 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-28707914

RESUMEN

The first elastic electron scattering has been successfully performed at the self-confining radioactive-isotope ion target (SCRIT) facility, the world's first electron scattering facility for SCRIT technique achieved high luminosity (over 10^{27} cm^{-2} s^{-1}, sufficient for determining the nuclear shape) with only 10^{8} target ions. While ^{132}Xe used in this time as a target is a stable isotope, the charge density distribution was first extracted from the momentum transfer distributions of the scattered electrons by comparing the results with those calculated by a phase shift calculation.

20.
Vet Pathol ; 54(5): 783-791, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28494700

RESUMEN

Oral and cutaneous tissues are the most frequent origin in canine squamous cell carcinoma (SSC). In SCC, changes in adhesion molecule expression and transition from epithelial to mesenchymal phenotype are thought to be important in development of invasive behavior of neoplastic cells at the leading front of the tumor. We therefore investigated histological invasive front grading and epithelial-mesenchymal transition (EMT) in both oral SCCs and cutaneous SCCs. EMT was assessed by evaluating immunohistochemical expression of E-cadherin, ß-catenin, desmoglein, vimentin, and N-cadherin. Regardless of the anatomic location, invasive front grading resulted in higher histological grades than grading of the surface. Most oral SCCs were of significantly higher histologic grade than cutaneous SCCs ( P < .01). Expression of E-cadherin, ß-catenin, and desmoglein was significantly lower in oral SCC compared with cutaneous SCC ( P < .01). A significant association was found between invasive front grading and loss of E-cadherin, ß-catenin, and desmoglein ( P < .01). Also, vimentin-positive neoplastic cells had low immunoreactivity of these adhesion molecules, and a few of these neoplastic cells were positive for N-cadherin. These results suggest not only E-cadherin and ß-catenin but also desmoglein as markers for predicting biological behavior of canine SCC. Depending on their primary sites, EMT correlates with biological behavior and therefore histological grade of canine SCC. We suggest that combining invasive front grading with assessment of immunohistochemical expression of E-cadherin, ß-catenin, and desmoglein may allow more accurate prediction of biological behavior of canine SCCs.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/veterinaria , Enfermedades de los Perros/patología , Transición Epitelial-Mesenquimal , Neoplasias de la Boca/veterinaria , Neoplasias Cutáneas/veterinaria , Animales , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/metabolismo , Perros , Inmunohistoquímica/veterinaria , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Clasificación del Tumor/veterinaria , Invasividad Neoplásica , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología
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