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1.
Phys Rev Lett ; 110(26): 263601, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23848874

RESUMEN

We have investigated the microwave response of a transmon qubit coupled directly to a transmission line. In a transmon qubit, owing to its weak anharmonicity, a single driving field may generate dressed states involving more than two bare states. We confirmed the formation of three-state dressed states by observing all of the six associated Rabi sidebands, which appear as either amplification or attenuation of the probe field. The experimental results are reproduced with good precision by a theoretical model incorporating the radiative coupling between the qubit and the microwave.

2.
Clin Exp Dermatol ; 34(5): e40-2, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19508474

RESUMEN

We report two patients with chronic tongue ulceration who were successfully treated using sulpiride. The clinical diagnosis was oral candidiasis related to long-term steroid treatment. The results of the culture test and cytological examination supported this diagnosis, but antifungal treatment was ineffective and the tongue pain in these patients became more severe. Furthermore, the pain could not be relieved by nonsteroidal anti-inflammatory drugs (NSAIDs). We therefore prescribed sulpiride in addition to NSAIDs to reduce the tongue pain. A consequent improvement in both pain severity and ulceration was observed 2-3 weeks after sulpiride administration.


Asunto(s)
Candidiasis Bucal/tratamiento farmacológico , Antagonistas de Dopamina/uso terapéutico , Úlceras Bucales/tratamiento farmacológico , Sulpirida/uso terapéutico , Enfermedades de la Lengua/tratamiento farmacológico , Anciano de 80 o más Años , Candidiasis Bucal/patología , Enfermedad Crónica , Femenino , Humanos , Úlceras Bucales/patología , Enfermedades de la Lengua/patología
3.
Tissue Eng ; 13(1): 87-99, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17518583

RESUMEN

Fabrication of implantable cartilaginous structures that could be secured in the joint defect could provide an alternative therapeutic approach to prosthetic joint replacement. Herein we explored the possibility of using biodegradable hydrogels in combination with a polyglycolic acid (PGA) scaffold to provide an environment propitious to mesenchymal stem cells (MSCs) chondrogenic differentiation. We examined the influence of type I collagen gel and alginate combined with PGA meshes on the extracellular matrix composition of tissue-engineered transplants. MSCs were isolated from young rabbits, expanded in monolayers, suspended in each hydrogel, and loaded on PGA scaffolds. All constructs (n=48) were cultured in serum-free medium containing transforming growth factor beta-1, under dynamic conditions in specially designed bioreactors for 3-6 weeks. All cell-polymer constructs had a white, shiny aspect, and retained their initial size and shape over the culture period. Their thickness increased substantially over time, and no shrinkage was observed. All specimens developed a hyalin-like extracellular matrix containing glycosaminoglycans (GAGs) and type II collagen, but significant differences were observed among the three different groups. In PGA/MSCs and collagen-PGA/MSCs constructs, the cell growth phase and the chondrogenic differentiation phase of MSCs occurred during the first 3 weeks. In alginate-PGA/MSCs constructs, cells remained round in the hydrogel and cartilage extracellular matrix deposition was delayed. However, at 6 weeks, alginate-PGA/MSCs constructs exhibited higher contents of GAGs and lower contents of type I collagen. These results suggest that the implied time for the transplantation of in vitro engineered constructs depends, among other factors, on the nature of the scaffold envisioned. In this study, we demonstrated that the use of a composite hydrogel-PGA scaffold supported the in vitro growth of implantable cartilaginous structures cultured in a bioreactor system.


Asunto(s)
Materiales Biocompatibles , Cartílago Hialino/trasplante , Trasplante de Células Madre Mesenquimatosas/métodos , Ingeniería de Tejidos/métodos , Alginatos/ultraestructura , Animales , Materiales Biocompatibles/síntesis química , Reactores Biológicos , Células de la Médula Ósea/citología , Células de la Médula Ósea/fisiología , Células de la Médula Ósea/ultraestructura , Adhesión Celular/fisiología , Técnicas de Cultivo de Célula , Colágeno Tipo I/síntesis química , Colágeno Tipo I/ultraestructura , Colágeno Tipo II/síntesis química , Colágeno Tipo II/ultraestructura , Ácido Glucurónico/fisiología , Ácidos Hexurónicos , Cartílago Hialino/fisiología , Cartílago Hialino/ultraestructura , Hidrogeles , Masculino , Células Madre Mesenquimatosas/química , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/ultraestructura , Microscopía Fluorescente , Ácido Poliglicólico , Conejos
4.
Nat Commun ; 8: 13984, 2017 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-28181489

RESUMEN

Improvement in secure transmission of information is an urgent need for governments, corporations and individuals. Quantum key distribution (QKD) promises security based on the laws of physics and has rapidly grown from proof-of-concept to robust demonstrations and deployment of commercial systems. Despite these advances, QKD has not been widely adopted, and large-scale deployment will likely require chip-based devices for improved performance, miniaturization and enhanced functionality. Here we report low error rate, GHz clocked QKD operation of an indium phosphide transmitter chip and a silicon oxynitride receiver chip-monolithically integrated devices using components and manufacturing processes from the telecommunications industry. We use the reconfigurability of these devices to demonstrate three prominent QKD protocols-BB84, Coherent One Way and Differential Phase Shift-with performance comparable to state-of-the-art. These devices, when combined with integrated single photon detectors, pave the way for successfully integrating QKD into future telecommunications networks.

5.
Circulation ; 102(19 Suppl 3): III259-62, 2000 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-11082398

RESUMEN

BACKGROUND: Despite recent progress in medical and surgical treatment, acute type B aortic dissection still carries a high mortality rate. We have developed a novel cylindrical balloon catheter for less invasive treatment to block the entry of the dissection and induce thrombotic occlusion of the false lumen. The balloon has the shape of a sheet when deflated but a double-cylinder shape when inflated. Therefore, aortic blood flow is maintained through the cylindrical lumen during balloon inflation. METHODS AND RESULTS: Six beagle dogs underwent a left thoracotomy at the 6th intercostal space. An acute dissection of 4-cm length was created surgically on the descending aorta. The balloon catheter was inserted through the distal descending aorta and advanced to the entry site. The balloon catheter was inflated for 6 hours. The blood flow in the descending aorta and the position of the balloon was monitored by color Doppler echovasculography. Four dogs were killed humanely on the following day and 2 dogs 10 days after the surgery. The descending aorta was examined macroscopically and microscopically in all dogs. In all dogs, the false lumen was occluded by thrombi. Although no dog had clinical evidence of distal thromboembolism, 2 of the 4 dogs that were killed on the second postoperative day had fresh mural thrombi in the true lumen. CONCLUSIONS: The false lumen of the acute type B aortic dissection was effectively occluded by the novel cylindrical balloon catheter in the canine experimental model. The thrombus formation in the true lumen is the problem to be solved.


Asunto(s)
Aorta Torácica/patología , Aorta Torácica/cirugía , Disección Aórtica/cirugía , Cateterismo/instrumentación , Procedimientos Quirúrgicos Vasculares/instrumentación , Enfermedad Aguda , Animales , Cateterismo/efectos adversos , Cateterismo/métodos , Modelos Animales de Enfermedad , Perros , Trombosis/etiología , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Procedimientos Quirúrgicos Vasculares/efectos adversos , Procedimientos Quirúrgicos Vasculares/métodos
6.
Int J Cardiol ; 102(2): 273-7, 2005 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-15982496

RESUMEN

BACKGROUND: PRKAR1A gene encodes the type 1A regulatory subunit of protein kinase A. The mutation of this gene causes Carney complex which is an autosomal dominant multiple neoplasia syndrome characterized by spotty pigmentations, endocrine overactivity and cardiac myxoma. We hypothesized that cardiac myxoma may be associated with PRKAR1A gene mutation and determined whether mutation in the PRKAR1A gene is the cause of familial and sporadic cardiac myxoma. METHODS: We studied seven patients (three males and four females) with cardiac myxoma. Two of them had familial cardiac myxoma complicated with Carney complex. The other five patients were characterized as sporadic cardiac myxomas. We analyzed the PRKAR1A gene of all patients by the polymerase chain reaction (PCR)-single-strand conformation method, followed with direct sequence analysis. RESULTS: We identified a novel mutation (494delTG) in exon 4A of the PRKAR1A gene in the patients with Carney complex. A 16-year-old proband had a left atrial myxoma, pituitary adenoma and skin pigmentation. His father also had left atrial myxoma and skin pigmentation. In contrast, no mutations in the PRKAR1A gene were identified in the other five patients with sporadic cardiac myxomas. CONCLUSIONS: These results suggest that mutation of the PRKAR1A gene may be associated with familial cardiac myxoma in Carney complex but may not be associated with sporadic cardiac myxoma.


Asunto(s)
ADN de Neoplasias/genética , Neoplasias Cardíacas/genética , Mutación , Mixoma/genética , Proteínas/genética , Adolescente , Adulto , Anciano , Alelos , Subunidad RIalfa de la Proteína Quinasa Dependiente de AMP Cíclico , Proteínas Quinasas Dependientes de AMP Cíclico , Ecocardiografía Transesofágica , Femenino , Marcadores Genéticos , Neoplasias Cardíacas/diagnóstico , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mixoma/diagnóstico , Linaje
7.
Biomaterials ; 24(12): 2077-82, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12628828

RESUMEN

Microporous, non-woven poly( epsilon -caprolactone) (PCL) scaffolds were made by electrostatic fiber spinning. In this process, polymer fibers with diameters down to the nanometer range, or nanofibers, are formed by subjecting a fluid jet to a high electric field. Mesenchymal stem cells (MSCs) derived from the bone marrow of neonatal rats were cultured, expanded and seeded on electrospun PCL scaffolds. The cell-polymer constructs were cultured with osteogenic supplements under dynamic culture conditions for up to 4 weeks. The cell-polymer constructs maintained the size and shape of the original scaffolds. Scanning electron microscopy (SEM), histological and immunohistochemical examinations were performed. Penetration of cells and abundant extracellular matrix were observed in the cell-polymer constructs after 1 week. SEM showed that the surfaces of the cell-polymer constructs were covered with cell multilayers at 4 weeks. In addition, mineralization and type I collagen were observed at 4 weeks. This suggests that electrospun PCL is a potential candidate scaffold for bone tissue engineering.


Asunto(s)
Huesos/patología , Poliésteres/química , Ingeniería de Tejidos , Animales , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/ultraestructura , Matriz Extracelular/metabolismo , Inmunohistoquímica , Microscopía Electrónica de Rastreo , Oxígeno/metabolismo , Polímeros/química , Ratas , Células Madre/metabolismo , Células Madre/ultraestructura , Factores de Tiempo
8.
J Biochem ; 129(4): 627-33, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11275564

RESUMEN

Collagen is generally incapable of capturing polypeptides such as growth factors in a specific manner. In this study, we established a collagen-binding growth factor (FNCBD-EGF) consisting of epidermal growth factor (EGF) and the fibronectin collagen-binding domain. A typical yield of FNCBD-EGF was approximately 200 microg/ml culture in an Escherichia coli expression system. This fusion protein bound to gelatin and fibrillar collagen sponges, and the bound protein was not effectively eluted even with 2 M NaCl. In addition, FNCBD-EGF bound to type I, II, III, or IV collagen-coated plates, and the specificity of binding was confirmed by competitive inhibition using fibronectin. FNCBD-EGF substantially stimulated cell growth after binding to collagen-coated culture plates, whereas EGF had no effect, indicating that this fusion protein acted as a collagen-associated growth factor. In an animal model of impaired wound healing, FNCBD-EGF, but not EGF, was retained with collagen sponges at wound sites 4 d after implantation, and repair of epidermis was observed underneath the sponges. These results suggested that our fusion protein with high collagen affinity would be useful for wound healing.


Asunto(s)
Colágeno/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Animales , Unión Competitiva , Western Blotting , División Celular/efectos de los fármacos , Línea Celular , Colágeno/antagonistas & inhibidores , Diabetes Mellitus/genética , Relación Dosis-Respuesta a Droga , Factor de Crecimiento Epidérmico/farmacología , Gelatina/metabolismo , Inmunohistoquímica , Ratones , Unión Proteica , Ratas , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Especificidad por Sustrato , Termodinámica , Heridas y Lesiones/metabolismo
9.
Ann Thorac Surg ; 60(5): 1430-1, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8526650

RESUMEN

We describe a technique for repairing the ventricular septal perforation using porcine pericardium tailored in a conical shape. This technique may allow a good operating view and facilitate suturing to the left ventricular cavity.


Asunto(s)
Pericardio/trasplante , Rotura Septal Ventricular/cirugía , Anciano , Anciano de 80 o más Años , Animales , Humanos , Masculino , Técnicas de Sutura , Porcinos , Trasplante Heterólogo , Ultrasonografía , Rotura Septal Ventricular/diagnóstico por imagen
10.
J Agric Food Chem ; 47(4): 1530-2, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10564011

RESUMEN

The lentinan contents in the Lentinus edodes fruit body during storage were examined by ELISA method using anti-lentinan antibodies. The lentinan content (12.8 mg.g(-)(1) dw) before storage decreased to 3.7 mg.g(-)(1) dw over 7 days at 20 degrees C. However, it only slightly decreased at 1 degrees C and only decreased to 9.3 mg. g(-)(1) dw at 5 degrees C. Glucanase activity, which seems to be associated with lentinan degradation, increased more during storage of L. edodes at 20 degrees C than it did at lower temperatures. In addition, only glucose was detected as a degraded product from lentinan by the glucanase. This suggested that this enzyme would fit the profile of an exo-type glucanase. Also, polyphenol oxidase activity, known as an index of freshness reduction in the mushroom, increased approximately 2.7-fold (to 61.5 units.mg(-)(1)) over 7 days during storage at 20 degrees C. However, its activity changed little during storage at lower temperatures. These results indicate that the reduction during storage of the quality of L. edodes as a functional food is accompanied by the decrease of lentinan, and by browning, and that exo-glucanase plays an important role in the decrease of lentinan content.


Asunto(s)
Lentinano/análisis , Hongos Shiitake/química , Ensayo de Inmunoadsorción Enzimática/métodos , Manipulación de Alimentos , Lentinano/metabolismo , Factores de Tiempo
11.
Intern Med ; 31(3): 380-4, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1611191

RESUMEN

A 54-year-old woman with anemia, diabetes mellitus and liver dysfunction was admitted to our hospital. Numerous binucleated erythroblasts in the bone marrow, a positive serum acidified test, and the presence of anti I and anti i antigens on the surface of her erythrocytes indicated that she had congenital dyserythropoietic anemia (CDA) Type II. Hemochromatosis was confirmed by a liver biopsy. This case is a sibling of a patient with CDA Type II reported by Omine et al in 1981 (Acta Haematol Jpn 44:1). They report that no physical or hematological abnormalities were found when she was examined at the age of 29 years. Twenty-five years later, she developed CDA Type II and hemochromatosis. This case indicates that long-term observation of the family members of a patient with CDA Type II is necessary.


Asunto(s)
Anemia Diseritropoyética Congénita/complicaciones , Hemocromatosis/complicaciones , Anemia Diseritropoyética Congénita/clasificación , Anemia Diseritropoyética Congénita/genética , Antígenos de Superficie , Médula Ósea/patología , Eritroblastos/patología , Membrana Eritrocítica/inmunología , Femenino , Hemocromatosis/diagnóstico , Humanos , Hígado/patología , Persona de Mediana Edad
12.
Artículo en Inglés | MEDLINE | ID: mdl-10807711

RESUMEN

OBJECTIVE: The purpose of this study was to investigate, by assessing speech intelligibility, the long-term usefulness of an artificial bilayer membrane as a mucosal substitute after glossectomy. STUDY DESIGN: Artificial membranes were grafted in 8 patients with intraoral defects after glossectomy. Five patients served as a control group and received only standard closure by suture after glossectomy. Speech intelligibility was evaluated by means of a standardized Japanese speech intelligibility test 6 months or more after the operation. RESULTS: The postoperative courses of all 13 patients were uneventful. Intelligibility scores of those who received grafts were better than those of the control group in the overall score, the glossal sounds score, and the rear portion sounds score. CONCLUSION: The artificial membrane was useful for the glossectomy as a long-term mucosal substitute, as well as for the short-term.


Asunto(s)
Glosectomía/métodos , Membranas Artificiales , Inteligibilidad del Habla , Adulto , Anciano , Animales , Bovinos , Colágeno , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Articulación del Habla , Resultado del Tratamiento
13.
J Exp Mar Biol Ecol ; 257(1): 73-86, 2001 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-11165300

RESUMEN

14C-labeled extracellular products of a natural microphytobenthic community and two species of benthic diatoms (Nitzschia hybridaeformis and Amphora coffeaeformis) were fractionated into extracellular dissolved organic carbon (14C-EDOC), organic carbon extracted with EDTA (14C-EDTA-extractable OC) and extracellular polymeric substances (14C-EPS). The biodegradation of this labeled extracellular organic carbon by bacteria in sediments was examined to determine the processes of enzymatic degradation of photosynthetically-produced extracellular organic carbon from microphytobenthos in an intertidal flat ecosystem. In addition, primary production as well as extracellular enzyme activities (beta- and alpha-glucosidase) were measured to evaluate the possible relationship between organic carbon production and microbiological degradation at the Isshiki intertidal flat in Mikawa Bay, Japan. With all three 14C-fractions extracted from a natural microphytobenthic assemblage and two species of benthic diatoms, more than 50% of the added substrates were mineralized within 24 h by the bacterial community in sediments. At that time, the percentage of high-molecular-weight compounds (>5 K MW) to total MW compounds of 14C-EDTA-extractable OC and 14C-EPS fractions decreased within 24 h from 50.9 to 6.6% and 74.5 to 11.1%, respectively. In situ, beta- and alpha-glucosidase activity in sediment was higher than in the seawater column (at a depth of 1 m), though the photosynthetic production of microphytobenthos was equal to that of phytoplankton. Based on our previous studies that microphytobenthos produced much more extracellular products than phytoplankton, it is assumed from these results that carbon flowing into the microbial loop through the mediation of enzymatic degradation of extracellular products in a benthic system exceeds that in the overlying water column.

14.
Int J Artif Organs ; 26(9): 783-92, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14655858

RESUMEN

OBJECTIVE: In situ tissue engineering using acellular xenografts is a new approach to autologous tissue regeneration. In the present study, we analyzed a new regeneration scaffold comprised of xenogenic acellular vessels in a dog model. DESIGN OF STUDY AND RESULTS: Xenogenic vascular conduits of porcine carotid arteries were acellularized by a 48-hour detergent incubation to extract all the cell components of the graft. The acellularisation procedure resulted in a complete removal of all cells. After this procedure, heparinization was performed sequentially to induce antithrombogenicity in the graft. The burst pressure of the graft was tested. The bursting pressure of the fresh vessels was 2.83 +/- 0.56 x 10(3) mmHg (377 +/- 75kPa, n = 6). After detergent treatment, the bursting pressure of the grafts was 2.50 +/- 0.48 x 10(3) mmHg (334 +/- 63 kPa, n = 6); after heparinization, it was 3.44 +/- 0.38 x 10(3) mmHg (459 +/- 51 kPa, n = 5). In vivo function was tested in a dog model by transplantation to the abdominal artery. By 18 weeks, endothelial cells were aligned as in normal, healthy artery over the surface of the entire graft. Fibroblasts and macrophages had infiltrated the graft from both inside and outside. The neointima contained normal layers of smooth muscle cells, which were identified by anti alpha-smooth muscle fiber antigen staining. CONCLUSIONS: The acellular heparinized xenograft has sufficient mechanical properties and was successfully replaced with host tissue, and is thus a promising new type of vascular prosthesis.


Asunto(s)
Bioprótesis , Prótesis Vascular , Arterias Carótidas/citología , Endotelio Vascular/fisiología , Regeneración , Ingeniería de Tejidos/métodos , Animales , Anticoagulantes/administración & dosificación , Aorta Abdominal/cirugía , Separación Celular , Perros , Endotelio Vascular/citología , Matriz Extracelular/trasplante , Heparina/administración & dosificación , Modelos Animales , Estrés Mecánico , Porcinos , Trombosis/prevención & control
15.
Kyobu Geka ; 47(7): 528-32, 1994 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-8057536

RESUMEN

We studied the influence of pleurotomy during harvesting IMA for CABG on postoperative pulmonary function. Ninety nine cases underwent CABG surgery from January 1991 to July 1992, were divided into three subgroups, 45 patients (subgroup AY 2) having bilateral IMAs graft with pleurotomy, 45 patients (subgroup AY 1) having unilateral IMA graft with pleurotomy, 9 patients (subgroup AN) having unilateral IMA graft or vein grafts without pleurotomy. Frequencies of chest X-rays abnormality such as elevation of diaphragm and accumulation of pleural effusion before discharge around 2 weeks after surgery, were not significantly different among three subgroups. 58 cases without chest X-rays abnormalities were divided into three subgroups in the same way. There was no case with late extubation or with postoperative pulmonary complication. At first we compared pre-with postoperative pulmonary function in each subgroups. Pulmonary function (VC, FEV1.0, peak flow, MMF, V50, V25) was significantly deteriorated in the patients with pleurotomy, while VC, FEV1.0, peak flow significantly decreased, and MMF, V50 and V25 tended to decrease in the patients without pleurotomy. Moreover, magnitude of change of pulmonary function from pre- to postoperative period were not different significantly among three subgroups. In conclusions pleurotomy itself didn't appear to influence postoperative morbidity.


Asunto(s)
Puente de Arteria Coronaria , Pulmón/fisiopatología , Pleura/cirugía , Femenino , Humanos , Masculino , Arterias Mamarias/trasplante , Persona de Mediana Edad , Periodo Posoperatorio , Pruebas de Función Respiratoria
16.
Nihon Geka Gakkai Zasshi ; 92(9): 1123-6, 1991 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-1944168

RESUMEN

To clarify the predictors of operative risk in the elderly, preoperative clinical features and postoperative short term outcome were retrospectively evaluated in 328 consecutive patients. Patients underwent coronary artery bypass or valvular surgery from July 1988 to December 1990 in our hospital: 78 patients were 70 years or older (elderly group) and 250 were younger than 70 years old (control group). Preoperative renal and respiratory function were slightly depressed in the elderly group than in the control group. Prolonged ventilatory support and the administration of inotropic agent were required in some elderly patients with renal or respiratory dysfunction. Neurological complications occurred more frequently in the elderly group than in the control group. Prolonged ventilatory support was needed in almost all the elderly patients with neurological complications. The operative mortality rate was similar in the two patient groups. In contrast, the hospital mortality rate was significantly higher in the elderly group than in the control group. The main causes of the higher hospital mortality in the elderly group was pulmonary infection and sepsis. These results suggest that the prolonged intensive care induces lethal infection and high hospital mortality in the elderly patients undergoing cardiac surgery.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Factores de Edad , Anciano , Humanos , Complicaciones Posoperatorias
17.
J Phys Condens Matter ; 24(47): 475702, 2012 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-23111056

RESUMEN

For epitaxial NbN films with thickness d, 2.0 nm ≤ d ≤ 20.5 nm, we observed a sharp superconducting transition, for which the transition temperature T(c) monotonically decreased with increasing 1/d. Regarding the suppression of T(c), the sheet resistance R(sq) dependence of T(c) closely fitted the Finkel'stein formula from localization theory, with a reasonable value of the electron mean free path comparable to atomic distance, which was used as a fitting parameter. On the other hand, the critical sheet resistance R(c), at which the superconducting-insulator transition was expected, was approximately one-third of the universal value R(q) = h/4e(2) suggested by the dirty boson model for self-duality. It is concluded that T(c) depression in the present NbN system is determined by localization theory but not the dirty boson model.

18.
Work ; 41 Suppl 1: 1471-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22316924

RESUMEN

We constructed an innovative experimental platform to study cross-situational consistency in driving behavior, conducted behavioral experiments, and reported the data obtained in the experiment. To discuss cross-situational consistency, we separated situations in which people use some systems to conduct tasks into three independent conceptual factors: environment, context, and system. We report the experimental results with the following systems: a laboratory system with a gaming controller and steering/pedal controllers and a real system, COMS an instrumented vehicle. The results are summarized as follows. 1) The individual behaviors in each system were stable, and consistency was retained. 2) The consistency of the behaviors was also confirmed when the participants drove using different interfaces in identical systems. 3) However, only slight correlation was observed across different systems in a specific situation where a strong high-order cognitive constraint (i.e., rapid driving) and a weak low-order cognitive constraint (driving with easy handling toward a straight-line course) were given.


Asunto(s)
Conducción de Automóvil , Ergonomía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Interfaz Usuario-Computador
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