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2.
Nanoscale ; 12(45): 23274-23281, 2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-33206097

RESUMEN

Recently, monolayer SnS, a two-dimensional group IV monochalcogenide, was grown on a mica substrate at the micrometer-size scale by the simple physical vapor deposition (PVD), resulting in the successful demonstration of its in-plane room temperature ferroelectricity. However, the reason behind the monolayer growth remains unclear because it had been considered that the SnS growth inevitably results in a multilayer thickness due to the strong interlayer interaction arising from lone pair electrons. Here, we investigate the PVD growth of monolayer SnS from two different feed powders, highly purified SnS and commercial phase-impure SnS. Contrary to expectations, it is suggested that the mica substrate surface is modified by sulfur evaporated from the Sn2S3 contaminant in the as-purchased powder and the lateral growth of monolayer SnS is facilitated due to the enhanced surface diffusion of SnS precursor molecules, unlike the growth from the highly purified powder. This insight provides a guide to identify further controllable growth conditions.

3.
Sci Rep ; 9(1): 14701, 2019 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-31605015

RESUMEN

Modulation of lithium-ion battery (LIB) anodes/cathodes with three-dimensional (3D) topographical hierarchy ridges, surface interfaces, and vortices promotes the power tendency of LIBs in terms of high-energy density and power density. Large-scale meso-geodesics offer a diverse range of spatial LIB models along the geodetically shaped downward/upward curvature, leading to open-ended movement gate options, and diffusible space orientations. Along with the primary 3D super-scalable hierarchy, the formation of structural features of building block egress/ingress, curvature cargo-like sphere vehicles, irregularly located serrated cuticles with abundant V-undulated rigidness, feathery tube pipe conifers, and a band of dagger-shaped needle sticks on anode/cathode electrode surfaces provides high performance LIB modules. The geodetically-shaped anode/cathode design enables the uniqueness of all LIB module configurations in terms of powerful lithium ion (Li+) movement revolving in out-/in- and up-/downward diffusion regimes and in hovering electron density for high-speed discharge rates. The stability of built-in anode//cathode full-scale LIB-model meso-geodesics affords an outstanding long-term cycling performance. The full-cell LIB meso-geodesics offered 91.5% retention of the first discharge capacity of 165.8 mAhg-1 after 2000 cycles, Coulombic efficiency of ~99.6% at the rate of 1 C and room temperature, and high specific energy density of ≈119 Wh kg-1. This LIB meso-geodesic module configuration may align perfectly with the requirements of the energy density limit mandatory for long-term EV driving range and the scale-up commercial manufactures.

6.
Sci Rep ; 8(1): 7975, 2018 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-29773826

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

7.
Sci Rep ; 7(1): 7816, 2017 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-28798398

RESUMEN

Strong magnetic fields, synchrotron emission, and Compton scattering are omnipresent in compact celestial X-ray sources. Emissions in the X-ray energy band are consequently expected to be linearly polarized. X-ray polarimetry provides a unique diagnostic to study the location and fundamental mechanisms behind emission processes. The polarization of emissions from a bright celestial X-ray source, the Crab, is reported here for the first time in the hard X-ray band (~20-160 keV). The Crab is a complex system consisting of a central pulsar, a diffuse pulsar wind nebula, as well as structures in the inner nebula including a jet and torus. Measurements are made by a purpose-built and calibrated polarimeter, PoGO+. The polarization vector is found to be aligned with the spin axis of the pulsar for a polarization fraction, PF = (20.9 ± 5.0)%. This is higher than that of the optical diffuse nebula, implying a more compact emission site, though not as compact as, e.g., the synchrotron knot. Contrary to measurements at higher energies, no significant temporal evolution of phase-integrated polarisation parameters is observed. The polarization parameters for the pulsar itself are measured for the first time in the X-ray energy band and are consistent with observations at optical wavelengths.

8.
Occup Med (Lond) ; 67(1): 75-77, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27694375

RESUMEN

Compression neuropathy of the common peroneal nerve (CPN) at the fibula head is a common condition, but it has not attracted attention in working environments. Here, we report a 38-year-old sewer pipe worker who presented with bilateral CPN palsy following 6h working with a squatting posture in a narrow sewer pipe. During the work, he could not stretch his legs sufficiently because of the confined space. His symptoms deteriorated with repetition of the same work for 1 week. Motor nerve conduction study showed conduction block at the fibula head of bilateral CPNs, compatible with compression neuropathy at this lesion. Three months after cessation of work requiring the causative posture, his symptoms and neurophysiological abnormalities had resolved completely. Almost all seven of his co-workers presented transiently with similar and milder symptoms, although one showed CPN palsy for 6 months. Prolonged squatting posture in a confined space causes acute compression neuropathy at the fibula head in the CPN. More attention should be paid to 'confined space worker's compression neuropathy'.


Asunto(s)
Artrogriposis/complicaciones , Neuropatía Hereditaria Motora y Sensorial/complicaciones , Nervio Peroneo/fisiopatología , Postura/fisiología , Adulto , Artrogriposis/diagnóstico , Neuropatía Hereditaria Motora y Sensorial/diagnóstico , Humanos , Masculino , Neuropatías Peroneas/complicaciones , Neuropatías Peroneas/diagnóstico , Neuropatía Tibial/complicaciones , Neuropatía Tibial/diagnóstico
9.
Br J Anaesth ; 117(6): 812-820, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27956680

RESUMEN

BACKGROUND: The analgesic efficacy of continuous transversus abdominis plane (TAP) blocks in comparison with that of single-injection TAP blocks is not clear. This randomized, triple-blind, placebo-controlled trial investigated the benefits of adding continuous TAP blocks to single-injection TAP blocks after a laparotomy. METHODS: Eighty consecutive patients undergoing midline laparotomy for gynaecological cancer were randomized and received bilateral TAP infusions with either ropivacaine 0.1% (n=40, Rop group) or normal saline (n=40, NS group) at 10 ml h-1 per side for 50 h after surgery. After surgery, bilateral oblique subcostal TAP blocks were performed using ropivacaine 0.1%, 50 ml per side, and then catheters were threaded into the bilateral TAPs. Subsequently, continuous TAP infusions and patient-controlled i.v. morphine administration were initiated. The primary outcome was cumulative morphine consumption by 24 h after TAP catheter placement. Secondary outcomes included pain scores, postoperative nausea and vomiting severity, and time to first ambulation and flatus. RESULTS: The cumulative morphine consumption (median [interquartile range]) 24 h after TAP catheter placement was lower in the Rop group (0.25 [0.11-0.48] mg kg-1) than in the NS group (0.44 [0.24-0.73] mg kg-1; 95% confidence interval difference in medians, -0.30 to - 0.03; P=0.01). No statistically significant differences were observed in the secondary outcomes, except for reduced pain scores in the Rop group obtained during coughing 1 and 24 h after TAP catheter placement. CONCLUSIONS: Addition of continuous TAP blocks to single-injection TAP blocks reduces pain and morphine consumption after a laparotomy for gynaecological cancer. CLINICAL TRIAL REGISTRATION: UMIN Clinical Trials Registry identification number UMIN000013449 (http://www.umin.ac.jp/ctr/index.htm).


Asunto(s)
Músculos Abdominales/efectos de los fármacos , Amidas/administración & dosificación , Analgesia/métodos , Anestésicos Locales/administración & dosificación , Neoplasias de los Genitales Femeninos/cirugía , Bloqueo Nervioso/métodos , Adulto , Anciano , Amidas/uso terapéutico , Anestésicos Locales/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Ropivacaína , Resultado del Tratamiento
10.
Anaesthesia ; 69(3): 231-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24447266

RESUMEN

Factors affecting the distribution of continuous thoracic paravertebral block have never been examined. We designed this prospective, double-blind study to check whether continuous thoracic paravertebral block with a higher ropivacaine concentration would provide a wider segmental sensory block spread. Sixty consecutive patients undergoing pulmonary lobectomy or segmentectomy were randomly allocated to receive continuous paravertebral infusion of either 0.2% or 0.5% ropivacaine (6 ml.h(-1) ). The primary outcome was the number of anaesthetised dermatomes as determined by loss of cold sensation 24 h after surgery. Twenty-seven patients per group were included in the final analysis. The median (IQR [range]) number of anaesthetised dermatomes 24 h after surgery was 4 (3-6 [1-9]) with ropivacaine 0.2% and 4 (3-6 [2-11]) with ropivacaine 0.5% (p = 0.66). Contrary to our expectation, the segmental spread of sensory block produced by continuous thoracic paravertebral block does not depend on ropivacaine concentration.


Asunto(s)
Amidas/farmacología , Anestésicos Locales/farmacología , Bloqueo Nervioso , Adulto , Anciano , Anciano de 80 o más Años , Amidas/administración & dosificación , Anestesia General , Anestesia Intravenosa , Anestésicos Intravenosos , Anestésicos Locales/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Fentanilo , Humanos , Pulmón/cirugía , Masculino , Persona de Mediana Edad , Náusea y Vómito Posoperatorios/epidemiología , Estudios Prospectivos , Ropivacaína , Ultrasonografía Intervencional , Adulto Joven
11.
Endoscopy ; 44(11): 1037-44, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23108772

RESUMEN

BACKGROUND AND STUDY AIMS: We have previously developed duodenal balloon-assisted direct cholangioscopy (DBA-DC) with an ultrathin endoscope (UTE). Here, we further evaluated the feasibility, safety, and diagnostic and therapeutic usefulness of DBA-DC using UTE. PATIENTS AND METHODS: 40 consecutive patients with biliary diseases were enrolled in a prospective observational feasibility study. We assessed the success rate, procedure time, durability of the UTE, and usefulness in diagnosis and therapy. We also evaluated safety, including cardiovascular alterations and biliary injury as complications of the procedure. RESULTS: DBA-DC was performed successfully in 37/40 patients (92.5%). The mean time to reach either biliary bifurcation or stricture was 11.8 ± 6.3 minutes. The procedure revealed 26 biliary stones, 5 cholangiocarcinomas, and 3 benign biliary strictures. Therapeutic procedures were performed in 16 patients (10 biliary lithotomies, 3 holmium-YAG laser lithotripsies, and 3 intraductal stent placements). No significant clinical complications related to DBA-DC were observed. Changes in cardiovascular responses and biliary biochemical parameters were minimal, except for leukocytosis in 8 patients. CONCLUSIONS: DBA-DC appears to be sufficiently feasible and may be useful as an alternative technique in cases that elude successful diagnosis and/or therapy with conventional endoscopic retrograde cholangiopancreatography (ERCP).


Asunto(s)
Enfermedades de los Conductos Biliares/diagnóstico , Endoscopía del Sistema Digestivo/instrumentación , Endoscopía del Sistema Digestivo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Endoscopía del Sistema Digestivo/efectos adversos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo
12.
Kyobu Geka ; 64(7): 537-9, 2011 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-21766701

RESUMEN

BACKGROUND: In a pediatric setting, the need for lifetime oral anticoagulation is increasing because of currency of extracardiac total cavo-pulmonary connection (TCPC) and pediatric valve surgery. We evaluated a new compact device "CoaguChek XS" for measuring prothrombin time-internatinal normalized ratio (PT-INR). METHODS: The international normalized ratio (INR) values obtained from 71 patients (223 samples) by a CoaguChek XS were compared with those obtained by a laboratory-based coagulation analyzer. RESULTS: The values from the CoaguChek XS had a significant correlation with the laboratory based results. (r2 = 0.92, p < 0.01, regression line y = 1.05 x -0.02). CONCLUSION: The CoaguChek XS will be useful in pediatric management.


Asunto(s)
Tiempo de Protrombina/instrumentación , Adolescente , Niño , Preescolar , Femenino , Puente Cardíaco Derecho , Válvulas Cardíacas/cirugía , Humanos , Lactante , Masculino , Adulto Joven
13.
Dis Esophagus ; 24(2): 92-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20659140

RESUMEN

Transnasal ultrathin esophagogastroduodenoscopy (N-EGD) with less gagging reflexes under non-sedation is likely suitable for the diagnosis of gastroesophageal reflux disease (GERD), however, N-EGD might have drawbacks, including its low image resolution. Limited information is available regarding the diagnosability of N-EGD for GERD. We compared the utility and gagging reflexes of three different endoscopies, including N-EGD, ultrathin transoral EGD (UTO-EGD) and conventional oral EGD (CO-EGD), in the diagnosis of GERD. We performed screening endoscopy in 1580 patients (N-EGD n=727, UTO-EGD n=599, CO-EGD n=254) and compared the frequency distributions of the severity of reflux esophagitis, hiatus hernia, and Barrett's epithelium to estimate the diagnostic performance of each endoscopy. We also analyzed patients' tolerability of endoscopy by the subjective evaluation of gagging reflexes. In the diagnosis of reflux esophagitis and Barrett's epithelium, there was no significant difference in the frequency distributions of the severity of the diseases among three EGDs. However, the incidence of Barrett's epithelium was higher than that in the previous nationwide survey of GERD in Japan. The evaluated size of hiatus hernia was smaller in N-EGD than in two other peroral endoscopies. The size of hiatus hernia correlated significantly with severity of gagging reflexes that was also lowest when diagnosed with N-EGD. N-EGD had an equivalent performance in the diagnosis of reflux esophagitis and Barrett's epithelium compared with CO-EGD. Enlargement of hiatus hernia induced by gagging reflexes was minimal in N-EGD, resulting in its better performance in the diagnosis of Barrett's epithelium.


Asunto(s)
Esófago de Barrett/diagnóstico , Endoscopía del Sistema Digestivo/métodos , Esofagitis Péptica/diagnóstico , Reflujo Gastroesofágico/diagnóstico , Hernia Hiatal/diagnóstico , Endoscopía del Sistema Digestivo/instrumentación , Femenino , Atragantamiento , Humanos , Masculino , Estudios Prospectivos
14.
Kyobu Geka ; 63(12): 1028-31, 2010 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-21066841

RESUMEN

A male baby was delivered by emergency cesarean section due to fetal distress at 30 weeks of gestational age with a birth weight of 813 g. By fetal echocardiography, the patient had been diagnosed with transposition of great arteries (type 1). Early two-staged arterial switch operation was planned after 34 gestational age avoiding intracranial hemorrhage under cardiopulmonary bypass. At 19 days of life, vegetation was revealed on the pulmonary valve by echocardiography, so he was diagnosed as infectious endocarditis. Cefotaxime and gamma-globulin were given intravenously for 4 weeks. While waiting for the increase in the body weight, desaturation from chronic respiratory distress syndrome was exacerbated. At 8 months old, urgent Senning operation was performed to improve desaturation. The patient was discharged at 20 post operative day. We conclude that Senning operation can be feasible operation in such a complicated case.


Asunto(s)
Transposición de los Grandes Vasos/cirugía , Procedimientos Quirúrgicos Cardiovasculares/métodos , Urgencias Médicas , Endocarditis/complicaciones , Humanos , Recién Nacido , Recien Nacido Prematuro , Síndrome de Dificultad Respiratoria del Recién Nacido/complicaciones
15.
Regul Toxicol Pharmacol ; 58(1): 114-20, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20447433

RESUMEN

L-proline (L-Pro) is a non-essential amino acid, and has become widely used as supplements and health foods, recently. A subchronic oral toxicity study of L-Pro was conducted with groups of 10 male and 10 female Fischer 344 rats fed a powder diet containing 0%, 0.625%, 1.25%, 2.5% and 5.0% of L-Pro for 90 days. No treatment-related clinical signs and mortality were noted. We observed no clear treatment-related effects with regard to body weight, food intake or urinalysis data. The average daily water intakes of the treated female groups were significantly increased compared to the controls. The hematology (red blood cell parameter) and serum biochemistry (glucose, blood urea nitrogen, creatinine or uric acid) of the treated male and/or female groups were lower than those of the control groups. However, these changes were lacked dose-dependence, and no abnormalities were found in corresponding pathological findings. In conclusion, the no-observed-adverse-effect-level (NOAEL) for L-Pro was determined to be a dietary dose of 5.0% (2772.9 mg/kg body weight/day for males and 3009.3mg/kg body weight/day for females) under the present experimental conditions.


Asunto(s)
Suplementos Dietéticos/toxicidad , Prolina/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Femenino , Pruebas Hematológicas , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Endogámicas F344 , Factores Sexuales , Bazo/efectos de los fármacos , Bazo/patología , Pruebas de Toxicidad
16.
Minerva Urol Nefrol ; 61(1): 55-66, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19417726

RESUMEN

Immunoglobulin A (IgA) nephropathy is recognized worldwide as the most common primary glomerulopathy. Although the mechanisms underlying the development of IgA nephropathy are gradually being clarified, their details remain unclear, and a radical cure for this condition has not yet been established. It has been clinically demonstrated that the immunoreactivities of intrarenal heme oxygenase-1 (HO-1) and 4-hydroxy-2-nonenal (4-HNE) markers of reactive oxygen species (ROS) and those of intrarenal angiotensinogen (AGT) and angiotensin II (Ang II) markers of renin angiotensin system (RAS) in IgA nephropathy patients were significantly increased as compared to those of control subjects. In an animal study, high IgA of ddY (HIGA) mice were used as an IgA nephropathy model and compared with BALB/c mice, which served as the control. The levels of markers for ROS (urinary 8-isoprostane and intrarenal 4-HNE), RAS (intrarenal AGT and Ang II), and renal damage in the HIGA mice were significantly increased as compared to those in the BALB/c mice. Moreover, an interventional study using HIGA mice demonstrated that the expressions of 2 lines of intrarenal ROS markers (4-HNE and HO-1), 2 lines of intrarenal RAS markers (AGT and Ang II) and renal damage decreased significantly in HIGA mice receiving treatment with the Ang II receptor blocker olmesartan but not in HIGA mice receiving treatment with RAS-independent antihypertensive drugs (hydralazine, reserpine, and hydrochlorothiazide) when compared with HIGA mice that were not treated. These data suggest that intrarenal ROS and RAS activation plays a pivotal role in the development of IgA nephropathy.


Asunto(s)
Glomerulonefritis por IGA/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sistema Renina-Angiotensina , Aldehídos/metabolismo , Angiotensina II/metabolismo , Angiotensinógeno/metabolismo , Animales , Biomarcadores/metabolismo , Inhibidores de Cisteína Proteinasa/metabolismo , Medicina Basada en la Evidencia , Glomerulonefritis por IGA/patología , Hemo-Oxigenasa 1/metabolismo , Humanos , Ratones , Vasoconstrictores/metabolismo
17.
Acta Chir Belg ; 109(1): 27-35, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19341192

RESUMEN

In the current review article, evidences on radical surgery for gastric cancer reported in the literature are highlighted. The authors conclude that extended lymphadenectomy offers a statistically significant survival benefit. This benefit is only evident if the operative mortality is less than 2%, as obtained in centers of excellence with a high-volume experience of resection of gastric cancer. Lymphadenectomy should no longer be considered only as a tool for cancer-staging, but also as a beneficial therapeutic measure.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Escisión del Ganglio Linfático/métodos , Neoplasias Gástricas/cirugía , Quimioterapia Adyuvante , Humanos , Metástasis Linfática , Pancreatectomía , Radioterapia Adyuvante , Ensayos Clínicos Controlados Aleatorios como Asunto , Esplenectomía , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Neoplasias Gástricas/radioterapia
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