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1.
Rev Sci Instrum ; 86(10): 103507, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26520955

RESUMEN

In magnetically confined torus plasmas, the local emission intensity, temperature, and flow velocity of atoms in the inboard and outboard scrape-off layers can be separately measured by a passive emission spectroscopy assisted by observation of the Zeeman splitting in their spectral line shape. To utilize this technique, a near-infrared interference spectrometer optimized for the observation of the helium 2(3)S-2(3)P transition spectral line (wavelength 1083 nm) has been developed. The applicability of the technique to actual torus devices is elucidated by calculating the spectral line shapes expected to be observed in LHD and QUEST (Q-shu University Experiment with Steady State Spherical Tokamak). In addition, the Zeeman effect on the spectral line shape is measured using a glow-discharge tube installed in a superconducting magnet.

2.
Rev Sci Instrum ; 85(2): 023502, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24593356

RESUMEN

We report development of a high dynamic range spectroscopic system comprising a spectrometer with 30% throughput and a camera with a low-noise fast-readout complementary metal-oxide semiconductor sensor. The system achieves a 10(6) dynamic range (∼20 bit resolution) and an instrumental function approximated by a Voigt profile with Gauss and Lorentz widths of 31 and 0.31 pm, respectively, for 656 nm light. The application of the system for line profile observations of the Balmer-α emissions from high temperature plasmas generated in the Large Helical Device is also presented. In the observed line profiles, emissions are detected in far wings more than 1.0 nm away from the line center, equivalent to neutral hydrogen atom kinetic energies above 1 keV. We evaluate atom density distributions in the core plasma by analyzing the line profiles.

3.
Rev Sci Instrum ; 84(7): 073509, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23902065

RESUMEN

The anisotropy of the electron velocity distribution function (EVDF) in plasmas can be deduced from the polarization of emissions induced by anisotropic electron-impact excitation. In this paper, we develop a compact thermal lithium atom beam source for spatially resolved measurements of the EVDF anisotropy in electron cyclotron resonance (ECR) plasmas. The beam system is designed such that the ejected beam has a slab shape, and the beam direction is variable. The divergence and flux of the beam are evaluated by experiments and calculations. The developed beam system is installed in an ECR plasma device with a cusp magnetic field, and the LiI 2s-2p emission (670.8 nm) is observed in low-pressure helium plasma. The two-dimensional distributions of the degree and direction of the polarization in the LiI emission are measured by a polarization imaging system. The evaluated polarization distribution suggests the spatial variation of the EVDF anisotropy.

4.
Rev Sci Instrum ; 81(3): 033106, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20370160

RESUMEN

We developed a spectrometer specialized for simultaneous observation of the hydrogen Balmer-alpha, -beta, -gamma lines and the Fulcher-alpha v(')=v(")=2 rovibronic transition band. The spectrometer was optimized for the light input coupled by nine optical fibers having 400 microm core diameters. The spectral resolutions were 0.02-0.03 nm for these wavelength ranges at the entrance slit width of 20 microm. The polarization resolved spectra of these emissions from the peripheral region of large helical device (LHD) plasmas were measured simultaneously and showed the polarization dependence coming from the magnetic field in the LHD plasma.

5.
J Microsc ; 209(Pt 3): 177-81, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12641758

RESUMEN

We have observed emission spectra of a CuCl film on a TiO2 prism surface(110) associated with the two-photon excitation of the exciton system in total reflection geometry. The I1 bound exciton emission, which resonantly appeared at the two-photon excitation of the Z3-longitudinal excitons and Z1,2-exciton band, was observed. The dependence of the emission intensities on the polarization of the excitation light was explained from the field intensity and the penetration depth of the evanescent light in CuCl accompanying the totally reflected light at the TiO2/CuCl interface.


Asunto(s)
Cobre/química , Fotones , Análisis Espectral , Diseño de Equipo , Rayos Láser , Modelos Estructurales , Óptica y Fotónica/instrumentación , Dispersión de Radiación , Análisis Espectral/métodos , Titanio/análisis
6.
Biosci Biotechnol Biochem ; 64(11): 2497-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11193426

RESUMEN

The extracellular Lipases A and C produced by Geotrichum sp. FO401B have a preference for the sn-1,3 and sn-2 positions of triglyceride, respectively. Total production of these lipases was increased by plant oils and tributyrin. Butyl Toyopearl column chromatography demonstrated that only Lipase C was produced in the presence of tributyrin. Lipase C hydrolysed natural fats except sardine oil preferentially at the sn-2 position, but it showed little stereoselectivity for triolein.


Asunto(s)
Geotrichum/efectos de los fármacos , Lipasa/metabolismo , Triglicéridos/metabolismo , Triglicéridos/farmacología , Inducción Enzimática , Geotrichum/enzimología , Lipasa/biosíntesis , Especificidad por Sustrato , Triglicéridos/química
8.
No To Shinkei ; 45(12): 1145-50, 1993 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-8123304

RESUMEN

Various materials and methods can be used for cranioplasty following external decompression craniotomy. We generally use cryopreserved autogenous bone for cranioplasty following external decompression. We assessed several factors, including histological changes in the stored bone, postoperative skull X-ray changes, postoperative changes in skull morphology, and the incidence of postoperative infections. The purpose of this study was determined if our materials and preservation methods were appropriate. The subjects were 110 patients who underwent cranioplasty using cryopreserved autogenous bone following external decompression at our hospital. They were followed up for at least one year. Bone fragments removed at the time of external decompression were stored at -40 degrees C an ultra-low temperature freezer and returned to room temperature before using them for cranioplasty. Follow-up skull x-ray films were obtained for 1-10 years postoperatively. Almost all of the 46 patients showed bone union at least one year after cranioplasty, but seven patients (15%) had marked bone resorption and bone atrophy after 3 years or longer. Five of these patients had a concomitant ventriculo-peritoneal shunt. Two of them developed collapse of the skull due to bone resorption, and this was considered to have been influenced by the shunt. Epidural empyema occurred postoperatively in five patients (4.5%), and staphylococci were the causative organisms in all five cases. The infections were completely cured by removal of the bone graft, debridement of the wound, and epidural drainage. Cranioplasty following external decompression craniotomy using cryopreserved autogenous bone fragments is a simple procedure, and the materials are inexpensive. Many of our patients who underwent cranioplasty using cryopreserved autogenous bone experienced no serious complications.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Trasplante Óseo , Criopreservación , Cráneo/cirugía , Adulto , Anciano , Atrofia , Resorción Ósea/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cráneo/patología , Trasplante Autólogo , Derivación Ventriculoperitoneal/efectos adversos
9.
No Shinkei Geka ; 21(9): 787-91, 1993 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-8377894

RESUMEN

General anesthesia for carotid endarterectomy (CEA) imposes the need for various monitorings of cerebral function during occlusion of the carotid artery. However, there is no ideal method for detecting all the signs of cerebrovascular insufficiency under general anesthesia. We suggest that the patient's neurological state is the best monitor of cerebral function. Therefore, our patients underwent cervical epidural anesthesia (EDA) enabling them to remain conscious while experiencing analgesia of the operated areas throughout the course of the operation. Five patients with cervical internal carotid artery stenosis were operated on under EDA with lidocaine. In all patients, EDA was effective in maintaining an analgesic state in the areas being operated on. It was able to do this either alone, or in combination with a light sedation. Under EDA, although there was no complete suppression of the patient's respiration, blood pressure was elevated beyond 200mmHg in three patients and depressed to 70mmHg in one patient transiently during the operation. But control of abnormal blood pressure was achieved easily by injections of calcium antagonist or ephedrine. When consciousness of two patients deteriorated during the clamping of the internal carotid artery, it completely recovered to its preoperative level after the insertion of an internal shunt. The patient's level of neurological condition became a good guide for predicting the need for an internal shunt during the periods of occlusion of the internal carotid artery. In conclusion, we suggest that EDA which is a safe and useful anesthesia should be employed in many patients who undergo CEA.


Asunto(s)
Anestesia Epidural , Endarterectomía Carotidea , Anciano , Anestesia Epidural/métodos , Estenosis Carotídea/cirugía , Infarto Cerebral/cirugía , Estado de Conciencia , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio
10.
Phys Rev Lett ; 70(9): 1303-1306, 1993 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10054342
11.
No To Shinkei ; 44(12): 1127-31, 1992 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-1296733

RESUMEN

32 cases of traumatic subdural hygroma (TSH) in adults with surgical treatment were retrospectively investigated by means by clinical features and CT findings. The cases consisted of 29 males and 3 females, aged 41 to 87 years (mean 69). Preparative CT scan of all cases revealed low density area and crescent shape in frontotemporal or frontoparietal subdural space. Half of the cases had bilateral lesions. At operation of TSH, color of subdural fluid collections was more water clear or xanthochromic than bloody. As a results, 22 out of 32 cases (69%) in TSH improved with surgical treatment. Many of effective cases of surgical treatment in TSH had short interval from trauma to operation and light disturbance of consciousness before operation. However, the other intracranial damage will also affect the clinical outcome of TSH, because the majority of cases in this study was accompanied by an intracranial damage including cerebral contusion, subarachnoid hemorrhage or intracranial hemorrhage. Nevertheless, surgical management for TSH was so effective that the operation should be undergone sooner interval from trauma, simultaneously considering the another intracranial lesions except TSH. But then, we experienced 7 cases (22%) of ventricular dilatation and 5 cases (16%) of chronic subdural hematoma in postoperative follow up CT scans. In 5 cases among the former, ventriculoperitonial shunt was done, and in 3 cases among the latter, burr hole evacuation was performed. Therefore, the postoperative course of TSH should require careful observation by CT scan and so on.


Asunto(s)
Traumatismos Craneocerebrales/complicaciones , Linfangioma/cirugía , Neoplasias Meníngeas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Linfangioma/diagnóstico por imagen , Linfangioma/etiología , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/etiología , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Espacio Subdural , Tomografía Computarizada por Rayos X
12.
No To Shinkei ; 44(9): 827-31, 1992 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-1476812

RESUMEN

Eighty-eight cases (114 hematomas) of chronic subdural hematoma (SDH) were treated surgically using irrigation with or without drainage. 13 cases (14.8%), 13 hematomas (11.4%) showed recurrence after the 1st operation. They were compared with non-recurrent cases using clinical reviews and serial CT findings. The result of the study showed that all of the patients in whom recurrence occurred were male and elderly (mean age 70.4 years). Many of these recurrences occurred in cases of bilateral SDH, on the left hematoma side, and at intervals within 7 days from the onset of clinical symptoms after the 1st operation. All recurrent cases were treated surgically using irrigation without drainage. In preoperative CT findings, it was shown that high density areas and small-sized hematomas were detected at a slightly higher rate in recurrent cases than in non recurrent cases. In postoperative CT findings, it was shown that many of the recurrent patients deteriorated during an interval from 2 weeks to 2 months. It was shown that non-recurrent patients had become almost normal by 3 months after the operation. Residual air volume into the subdural space within 7 days in recurrent cases was greater than in non-recurrent cases. Therefore, using irrigation with drainage, planning the operative timing, and reduction of residual air volume into subdural space are proposed as suitable means to avoid recurrence of SDH. Patients of SDH need postoperative follow-up during an interval up to 3 months.


Asunto(s)
Hematoma Subdural/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Femenino , Hematoma Subdural/etiología , Hematoma Subdural/cirugía , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Irrigación Terapéutica
14.
16.
No Shinkei Geka ; 12(11): 1293-7, 1984 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-6514126

RESUMEN

Clinical applications of newly developed shunt system for carotid endarterectomy were described. The shunt is a silicone tube equipped with balloons at both ends (Biballoon indwelling intraluminal shunt). The blood leak from the gap between a shunt tube and the inner wall of the carotid artery is prevented by inflating balloons after shunt insertion. This shunt system was used in seven cases of cerebral infarction resulted from the carotid stenosis and was proved to be more convenient than other known shunts.


Asunto(s)
Arterias Carótidas/cirugía , Infarto Cerebral/cirugía , Endarterectomía/métodos , Anciano , Animales , Arteriopatías Oclusivas/cirugía , Enfermedades de las Arterias Carótidas/cirugía , Perros , Endarterectomía/instrumentación , Femenino , Humanos , Persona de Mediana Edad , Elastómeros de Silicona
17.
J Neurosurg ; 61(4): 748-51, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6088732

RESUMEN

beta-Endorphin was measured in cerebrospinal fluid (CSF) and plasma in patients with cerebral infarction at acute (4 to 48 hours) and chronic (1 month) stages. Only CSF samples obtained in the acute stage showed beta-endorphin values that were statistically higher than those measured in a control population. This finding suggests that infarction at its acute stage gives rise to an increased release of beta-endorphin. Such a mechanism is consistent with the possibility that the reported therapeutic effect of naloxone in cerebral ischemic lesions may result in part from the antagonism of the centrally released endorphin, beta-endorphin.


Asunto(s)
Infarto Cerebral/líquido cefalorraquídeo , Endorfinas/líquido cefalorraquídeo , Adulto , Anciano , Infarto Cerebral/sangre , Infarto Cerebral/tratamiento farmacológico , Endorfinas/sangre , Humanos , Persona de Mediana Edad , Naloxona/uso terapéutico , betaendorfina
18.
J Neurosurg ; 60(4): 861-3, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6707760

RESUMEN

The authors describe an indwelling intraluminal shunt for carotid endarterectomy. The device is equipped with balloons at both ends to prevent bleeding and to hold the tube in place. The design permits use of a small tube which facilitates insertion, and prevents intimal damage and limitation of exposure of arterial plaque.


Asunto(s)
Arterias Carótidas/cirugía , Endarterectomía/instrumentación , Humanos
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