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1.
Rev Sci Instrum ; 92(5): 053516, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243235

RESUMEN

The Faraday-effect based polarimeter and interferometer are developed for non-perturbation magnetic field and density measurements on the Keda Reconnection eXperiment (KRX) device. The magnetic reconnection is externally driven by a pair of parallel current plates. To design this instrument and provide an alternative way to facilitate theory-experiment comparisons via forward modeling of the diagnostics process with full plasma dynamics given by simulation, we develop a synthetic diagnostics based on 2D photonic integrated circuit simulation for magnetic reconnection on the KRX. The view-line geometry is optimized and wavelengths (1 mm) of the polarimeter and interferometer are selected to ensure the sensitivity of measurement on the KRX. We have simulated magnetic reconnection on the x-line (x-z plane) with horizontal viewing and vertical viewing for line of sight measurements. It is found that the current sheet width and indicator of magnetic reconnection can be inferred directly from the dynamics of Faraday rotation even with the line-integrated character of polarimeter-interferometer diagnostics.

2.
Sci Rep ; 5: 17086, 2015 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-26597458

RESUMEN

Magnetization measurements have been carried out on a series of carefully prepared single-phase Mn(1+x)Ga (0

3.
Science ; 336(6081): 567-70, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22491094

RESUMEN

Observations with the Venus Express magnetometer and low-energy particle detector revealed magnetic field and plasma behavior in the near-Venus wake that is symptomatic of magnetic reconnection, a process that occurs in Earth's magnetotail but is not expected in the magnetotail of a nonmagnetized planet such as Venus. On 15 May 2006, the plasma flow in this region was toward the planet, and the magnetic field component transverse to the flow was reversed. Magnetic reconnection is a plasma process that changes the topology of the magnetic field and results in energy exchange between the magnetic field and the plasma. Thus, the energetics of the Venus magnetotail resembles that of the terrestrial tail, where energy is stored and later released from the magnetic field to the plasma.

4.
Toxicon ; 39(8): 1203-10, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11306131

RESUMEN

A fibrin(ogen)olytic serine protease from Trimeresurus jerdonii venom was identified and purified to SDS-polyacrylamide gel electrophoresis homogeneity. It is a single chain polypeptide with a molecular weight of 32kDa under reduced condition and 28kDa under non-reduced condition, respectively. The venom protease catalysed the hydrolysis of some chromogenic substrates such as S2238, S2160, S2302 and S2251. It degraded Bbeta-chain of human fibrinogen preferentially. Also the enzyme degraded fibrin directly. Its enzymatic activity was completely inhibited by phenylmethylsulfonyl fluoride (PMSF), but not affected by EDTA. That suggested it was a serine protease. N-terminal sequence of the purified component showed high homology with other snake venom serine proteases.


Asunto(s)
Venenos de Crotálidos/química , Serina Endopeptidasas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Fibrina/metabolismo , Fibrinógeno/metabolismo , Ratones , Datos de Secuencia Molecular , Conejos , Serina Endopeptidasas/química , Serina Endopeptidasas/metabolismo , Inhibidores de Serina Proteinasa/farmacología
5.
Opt Lett ; 26(24): 1993-5, 2001 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18059756

RESUMEN

What is believed to be the first planar optical waveguide was formed in BiB(3)O(6) (BIBO) crystal by 2.8-MeV He(+)-ion implantation with a dose of 2x10(16)ions/cm (2) and 2.8-MeV P(+)-ion implantation with a dose of 1x10(14)ions/cm (2) at room temperature. We observed 21 darks modes for the He(+)-ion-implanted BIBO waveguides and four dark modes for the P(+)-ion-implanted waveguides. The refractive-index profile of the He(+)-implanted BIBO waveguide was analyzed. The data also suggest that the BIBO waveguides formed by MeV He(+)-ion and P(+)-ion implantation differ in their developing mechanisms.

6.
Toxicon ; 38(9): 1225-36, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10736476

RESUMEN

From the venom of Trimeresurus jerdonii, a distinct thrombin-like enzyme, called jerdonobin, was purified by DEAE A-25 ion-exchange chromatography, Sephadex G-75 gel filtration, and fast protein liquid chromatography (FPLC). SDS-PAGE analysis of this enzyme shows that it consists of a single polypeptide chain with a molecular weight of 38,000. The NH(2)-terminal amino acid sequence of jerdonobin has great homology with venom thrombin-like enzymes documented. Jerdonobin is able to hydrolyze several chromogenic substrates. The enzyme directly clots fibrinogen with an activity of 217 NIH units/mg. The fibrinopeptides released, identified by HPLC, consisted of fibrinopeptide A and a small amount of fibrinopepide B. The activities of the enzyme were inhibited by phenylmethylsulfonyl fluoride (PMSF) and p-nitrophenyl-p-guanidinobenzoate (NPGB). However, metal chelator (EDTA) had no effect on it, indicating it is venom serine protease.


Asunto(s)
Venenos de Crotálidos/enzimología , Serina Endopeptidasas/química , Trombina/química , Trimeresurus , Secuencia de Aminoácidos , Animales , Coagulación Sanguínea/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Factor XIII/efectos de los fármacos , Fibrina/química , Fibrinógeno/química , Hemorragia/inducido químicamente , Ratones , Datos de Secuencia Molecular , Peso Molecular , Agregación Plaquetaria/efectos de los fármacos , Serina Endopeptidasas/aislamiento & purificación , Inhibidores de Serina Proteinasa/farmacología , Espectrofotometría Ultravioleta , Especificidad por Sustrato , Trombina/aislamiento & purificación
7.
Artículo en Inglés | MEDLINE | ID: mdl-10622430

RESUMEN

A nerve growth factor (NGF) was isolated from the venom of Chinese cobra (Naja naja atra) by ion exchange chromatography, gel filtration and fast protein liquid chromatography (FPLC). The N-terminal sequence of 22 amino acid residues was identical with other NGFs previously purified from the venom of the same genus. The NGF monomer molecular weight was estimated to be 13,500 by reducing SDS-PAGE and the isoelectric point was determined to be 7.2 by isoelectric focusing electrophoresis. NGF improved the epididymal sperm motility of male rats and increased the pregnancy rate and fetus number of mated female rats. The serum levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) of male rats administrated NGF + gossypol was lower than that of male rats administrated gossypol. Histological sections of testes and epididymides showed that NGF reduced the destructive effects of gossypol on rat testes.


Asunto(s)
Venenos Elapídicos/química , Genitales Masculinos/efectos de los fármacos , Factor de Crecimiento Nervioso/farmacología , Animales , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Femenino , Genitales Masculinos/fisiología , Masculino , Factor de Crecimiento Nervioso/aislamiento & purificación , Embarazo , Ratas , Ratas Wistar
8.
Scand J Work Environ Health ; 11 Suppl 4: 20-5, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3832431

RESUMEN

Fifty-three workers in a battery factory, 52 solderers in a television factory, and 50 embroidery workers (a reference group) were studied. The average air lead levels of the three workplaces were 0.578 mg/m3, 0.002 mg/m3, and 0.001 mg/m3, respectively. Adverse effects in terms of clinical manifestations and biochemical criteria were evident among the battery factory workers. A significant dose-response relationship existed between the toxic effects and the air lead levels. The solderers showed no apparent abnormalities in comparison with the embroidery workers. The early clinical manifestations were dysfunction of the central nervous system, indigestion, arthralgia, and myalgia in the extremities. A positive association was observed between the prevalence of fatigue, mild abdominal pain, and arthralgia and the blood lead (PbB), urinary lead (PbU), and zinc protoporphyrin (ZPP) levels. The symptomatic threshold values of PbB, PbU, and ZPP were 30 micrograms/dl (1.5 mumol/l), 0.045 mg/l (0.2 mumol/l), and 40 micrograms/dl (0.7 mumol/l), respectively. The PbB, PbU, free erythrocyte protoporphyrin, and ZPP levels and the blood aminolevulinic dehydratase ratio could be used as indicators of lead exposure, although ZPP is preferred for a preventive monitoring program. The motor and sensory conduction velocities of the median nerve were slower in the exposed groups than in the reference group. No effects on behavioral function were observed among the solderers.


Asunto(s)
Intoxicación por Plomo/diagnóstico , Plomo , Enfermedades Profesionales/diagnóstico , Enfermedades del Sistema Nervioso Central/inducido químicamente , China , Enfermedades del Sistema Digestivo/inducido químicamente , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Artropatías/inducido químicamente , Masculino , Enfermedades Musculares/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Ocupaciones , Factores de Tiempo
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