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2.
Nanoscale ; 12(45): 23274-23281, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33206097

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-31605015

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-29773826

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-28798398

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-27694375

RESUMO

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'.


Assuntos
Artrogripose/complicações , Neuropatia Hereditária Motora e Sensorial/complicações , Nervo Fibular/fisiopatologia , Postura/fisiologia , Adulto , Artrogripose/diagnóstico , Neuropatia Hereditária Motora e Sensorial/diagnóstico , Humanos , Masculino , Neuropatias Fibulares/complicações , Neuropatias Fibulares/diagnóstico , Neuropatia Tibial/complicações , Neuropatia Tibial/diagnóstico
9.
Br J Anaesth ; 117(6): 812-820, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27956680

RESUMO

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).


Assuntos
Músculos Abdominais/efeitos dos fármacos , Amidas/administração & dosagem , Analgesia/métodos , Anestésicos Locais/administração & dosagem , Neoplasias dos Genitais Femininos/cirurgia , Bloqueio Nervoso/métodos , Adulto , Idoso , Amidas/uso terapêutico , Anestésicos Locais/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Ropivacaina , Resultado do Tratamento
10.
Anaesthesia ; 69(3): 231-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24447266

RESUMO

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.


Assuntos
Amidas/farmacologia , Anestésicos Locais/farmacologia , Bloqueio Nervoso , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidas/administração & dosagem , Anestesia Geral , Anestesia Intravenosa , Anestésicos Intravenosos , Anestésicos Locais/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fentanila , Humanos , Pulmão/cirurgia , Masculino , Pessoa de Meia-Idade , Náusea e Vômito Pós-Operatórios/epidemiologia , Estudos Prospectivos , Ropivacaina , Ultrassonografia de Intervenção , Adulto Jovem
11.
Endoscopy ; 44(11): 1037-44, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23108772

RESUMO

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).


Assuntos
Doenças dos Ductos Biliares/diagnóstico , Endoscopia do Sistema Digestório/instrumentação , Endoscopia do Sistema Digestório/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia do Sistema Digestório/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
12.
Kyobu Geka ; 64(7): 537-9, 2011 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-21766701

RESUMO

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.


Assuntos
Tempo de Protrombina/instrumentação , Adolescente , Criança , Pré-Escolar , Feminino , Derivação Cardíaca Direita , Valvas Cardíacas/cirurgia , Humanos , Lactente , Masculino , Adulto Jovem
13.
Dis Esophagus ; 24(2): 92-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20659140

RESUMO

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.


Assuntos
Esôfago de Barrett/diagnóstico , Endoscopia do Sistema Digestório/métodos , Esofagite Péptica/diagnóstico , Refluxo Gastroesofágico/diagnóstico , Hérnia Hiatal/diagnóstico , Endoscopia do Sistema Digestório/instrumentação , Feminino , Engasgo , Humanos , Masculino , Estudos Prospectivos
14.
Kyobu Geka ; 63(12): 1028-31, 2010 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-21066841

RESUMO

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.


Assuntos
Transposição dos Grandes Vasos/cirurgia , Procedimentos Cirúrgicos Cardiovasculares/métodos , Emergências , Endocardite/complicações , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Síndrome do Desconforto Respiratório do Recém-Nascido/complicações
15.
Regul Toxicol Pharmacol ; 58(1): 114-20, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20447433

RESUMO

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.


Assuntos
Suplementos Nutricionais/toxicidade , Prolina/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Testes Hematológicos , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Fatores Sexuais , Baço/efeitos dos fármacos , Baço/patologia , Testes de Toxicidade
16.
Minerva Urol Nefrol ; 61(1): 55-66, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19417726

RESUMO

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.


Assuntos
Glomerulonefrite por IGA/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sistema Renina-Angiotensina , Aldeídos/metabolismo , Angiotensina II/metabolismo , Angiotensinogênio/metabolismo , Animais , Biomarcadores/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Medicina Baseada em Evidências , Glomerulonefrite por IGA/patologia , Heme Oxigenase-1/metabolismo , Humanos , Camundongos , Vasoconstritores/metabolismo
17.
Acta Chir Belg ; 109(1): 27-35, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19341192

RESUMO

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.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Excisão de Linfonodo/métodos , Neoplasias Gástricas/cirurgia , Quimioterapia Adjuvante , Humanos , Metástase Linfática , Pancreatectomia , Radioterapia Adjuvante , Ensaios Clínicos Controlados Aleatórios como Assunto , Esplenectomia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/radioterapia
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