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1.
Rev Sci Instrum ; 87(11): 11D615, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910421

RESUMO

A new tracer-encapsulated solid pellet (TESPEL) injection system has been developed additionally for the LHD heliotron. This system has three-dimensionally bended guide tubes, which allows us to inject the TESPEL obliquely on a poloidal cross-section of the LHD plasma. Consequently, this system enables us to control a tracer-impurity-deposited location more precisely. Moreover, this system can make it possible for the tracer impurity to be deposited even only inside the ergodic region (outside a last closed flux surface of the LHD plasma). A stereoscopic fast camera system has been also developed for capturing a three-dimensional TESPEL trajectory.

2.
Appl Opt ; 54(22): 6832-40, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26368099

RESUMO

We achieved a highly sensitive method for observing the motion of colloidal particles in a flowing suspension using a self-mixing laser Doppler velocimeter (LDV) comprising a laser-diode-pumped thin-slice solid-state laser and a simple photodiode. We describe the measurement method and the optical system of the self-mixing LDV for real-time measurements of the motion of colloidal particles. For a condensed solution, when the light scattered from the particles is reinjected into the solid-state laser, the laser output is modulated in intensity by the reinjected laser light. Thus, we can capture the motion of colloidal particles from the spectrum of the modulated laser output. For a diluted solution, when the relaxation oscillation frequency coincides with the Doppler shift frequency, fd, which is related to the average velocity of the particles, the spectrum reflecting the motion of the colloidal particles is enhanced by the resonant excitation of relaxation oscillations. Then, the spectral peak reflecting the motion of colloidal particles appears at 2×fd. The spectrum reflecting the motion of colloidal particles in a flowing diluted solution can be measured with high sensitivity, owing to the enhancement of the spectrum by the thin-slice solid-state laser.

3.
Rev Sci Instrum ; 86(4): 043505, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25933860

RESUMO

Experimental data on spatial distributions of a pellet cloud electron density are necessary for the development of many applications of pellet injection, namely, plasma fuelling, discharge control, and plasma diagnostics. An improved approach of electron density measurements inside the cloud of a polystyrene pellet ablating in hot plasma of the large helical device is described. Density values of (1-30) × 10(16) cm(-3) depending on the background plasma parameters and distance from the solid pellet were measured.

4.
Indian J Pharm Sci ; 77(2): 237-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26009660

RESUMO

Piper claussenianum inflorescences crude methanol extract was tested for hypoglycemic effect in streptozotocin-induced diabetic rats. The blood glucose levels of rats treated with methanol extract were reduced from 318.4±28.1 mg/dl before treatment to 174.2±38.3 mg/dl after 12 days of treatment (P<0.05). Phytochemical studies were carried out on inflorescences methanol crude extract in order to investigate the possible metabolites responsible for the pharmacological properties of the extract. After chromatographic procedures, three flavonoids were isolated and characterized. The major compound 2',6'-dihydroxy-4'-methoxychalcone was also tested. Rats that received the chalcone content also displayed a reduction in blood glucose levels from 277.4±7.7 mg/dl before treatment to 158.8±9.2 mg/dl after 12 days of treatment (P<0.05). The results suggest this chalcone is one of the metabolite responsible for the blood glucose levels reduction in rats with streptozotocin-induced diabetes. The inflorescence crude extract of P. claussenianum was found to be composed mainly by flavonoids and may be a potential natural source of compounds with hypoglycemic properties.

5.
Br Poult Sci ; 56(2): 225-31, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25561085

RESUMO

1. To clarify the underlying mechanism of hepatic fat accretion due to methionine (Met) deficiency in broiler chickens, the present study investigated the effect of Met deficiency on the hepatic carnitine palmitoyltransferase (CPT) system, which imports fatty acids into mitochondria. 2. Fifteen-d-old male meat-type chickens were fed on either a control diet (containing 0.52 g/100 g Met) or a Met-deficient diet (containing 0.27 g Met/100 g). After a 10-d feeding period, the birds were killed by decapitation and their livers excised to determine hepatic CPT1 and CPT2 mRNA levels and for the related hepatic fatty acid-supported mitochondrial respiration to be measured. 3. Met deficiency decreased body weight gain and feed efficiency and increased hepatic lipid content compared to the control group. Whereas the hepatic CPT2 mRNA level in the Met-deficient group remained unchanged compared to that of the control group, the CPT1 mRNA level was decreased in the Met-deficient group and CPT1-dependent hepatic mitochondrial respiration was impaired. 4. Our results suggest that the hepatic lipid accretion that occurs in response to Met deficiency might be attributable to the impairment of CPT1-mediated fatty acid import into mitochondria.


Assuntos
Carnitina O-Palmitoiltransferase/metabolismo , Galinhas/metabolismo , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Metionina/deficiência , Ração Animal/análise , Animais , Dieta/veterinária , Fígado/metabolismo , Masculino
6.
Oncogene ; 32(27): 3286-95, 2013 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-22847613

RESUMO

The tumor suppressor gene p53 has been implicated in the regulation of epithelial-mesenchymal transition (EMT) and tumor metastasis by regulating microRNA (miRNA) expression. Here, we report that mutant p53 exerts oncogenic functions and promotes EMT in endometrial cancer (EC) by directly binding to the promoter of miR-130b (a negative regulator of ZEB1) and inhibiting its transcription. We transduced p53 mutants into p53-null EC cells, profiled the miRNA expression by miRNA microarray and identified miR-130b as a potential target of mutant p53. Ectopic expression of p53 mutants repressed the expression of miR-130b and triggered ZEB1-dependent EMT and cancer cell invasion. Loss of an endogenous p53 mutation increased the expression of miR-130b, which resulted in reduced ZEB1 expression and attenuation of the EMT phenotype. Furthermore, re-expression of miR-130b suppressed mutant p53-induced EMT and ZEB1 expression. Importantly, the expression of miR-130 was significantly reduced in EC tissues, and patients with higher expression levels of miR-130b survived longer. These data provide a novel understanding of the roles of p53 gain-of-function mutations in accelerating tumor progression and metastasis through modulation of the miR-130b-ZEB1 axis.


Assuntos
Neoplasias do Endométrio/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Progressão da Doença , Neoplasias do Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Invasividade Neoplásica/genética , Transdução de Sinais/fisiologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco
7.
Rev Sci Instrum ; 83(10): 10D920, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126922

RESUMO

The particle loss in a helical plasma can be found by measuring the angular distribution of the energetic neutral particles using the angularly resolved multi-sightline neutral particle analyzer (ARMS). In ARMS, the AXUV detector with 20 segments usually used as UV monitor is utilized as the particle detector. Two ARMSs, which are installed with perpendicular and tangential views are operated for measuring the real time neutral particle distribution and investigating the particle loss.

8.
Phys Rev Lett ; 107(11): 115001, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-22026678

RESUMO

This Letter presents the discovery of macroscale electron temperature fluctuations with a long radial correlation length comparable to the plasma minor radius in a toroidal plasma. Their spatiotemporal structure is characterized by a low frequency of ∼1-3 kHz, ballistic radial propagation, a poloidal or toroidal mode number of m/n=1/1 (or 2/1), and an amplitude of ∼2% at maximum. Nonlinear coupling between the long-range fluctuations and the microscopic fluctuations is identified. A change of the amplitude of the long-range fluctuation is transmitted across the plasma radius at the velocity which is of the order of the drift velocity.

9.
Artigo em Inglês | MEDLINE | ID: mdl-20656050

RESUMO

This study was designed to elucidate physiological changes of skeletal muscle mitochondria from broiler chickens (Gallus gallus) during chronic heat exposure. Chickens (19-day-old) were exposed to either constant heat stress (34 degrees C) or kept at control temperature (24 degrees C) for 14days. Mitochondrial ROS production for control group showed little changes during the experimental periods, whereas that for the heat-stressed group was increased after 3, 5 and 9days of heat exposure and returned to original levels at day 14. Mitochondrial membrane potential in state 4 for heat-stressed birds was higher than those of control birds after 3 and 5days, but was not at day 14. Mitochondrial oxygen consumption rate in state 3 was increased after 3 and 5days, and also returned to original levels by day 14. These results suggest that chronic heat stress induces increased ROS production in skeletal muscle mitochondria, probably via elevation of the membrane potential in state 4, resulting from enhanced oxygen consumption in the initial stage of heat exposure. These physiological changes were no longer observed at day 14, possibly because the animals had acclimatized to environmental heat stress.


Assuntos
Resposta ao Choque Térmico/fisiologia , Mitocôndrias Musculares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Galinhas , Masculino , Potencial da Membrana Mitocondrial , Consumo de Oxigênio
10.
Rev Sci Instrum ; 79(10): 10E518, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044500

RESUMO

It is very important to investigate the confinement of alpha particles, which will be produced by nuclear reactions in ITER and fusion reactors. The pellet charge exchange (PCX) measurement is one of the most powerful methods because it can directly provide the profile of the alpha particle energy spectra in a plasma. In the large helical device, PCX using tracer encapsulated solid pellet (TESPEL) has been tried in many hydrogen and helium plasmas, including helium accelerated by using the cyclotron resonance heating. In the PCX, we use the compact neutral particle analyzer without simultaneous mass separation ability. The helium particle measurement can be achieved by the application of voltage in the condenser plate. The scattering of hydrogen particle is carefully considered during the estimation of the helium amount. The radial helium profiles can also be obtained by comparing four TESPEL injection shots with/without higher harmonic fast wave heating and at applied plate voltages for He or H, respectively.

11.
Rev Sci Instrum ; 79(10): 10F311, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044624

RESUMO

A feasible approach in obtaining experimental data on the angular dependence of the ion distribution function in a fusion plasma is to perform angle-resolved measurements of kinetic energy spectra of escaping neutral atoms. A general calculation scheme has been developed and realized as a FORTRAN code that has a predictive force to simulate the experimentally measurable anisotropic distributions and random samples of escaping neutral atom kinetic energies for any given angle-dependent ion distribution law, electron density, and temperature profiles, plasma composition, magnetic surface structure, and experiment geometry on any toroidal plasma device with magnetic confinement. As a particular application of the method to a specific experiment, measured signals for all 20 channels of the angle-resolved multisightline neutral particle analyzer on Large Helical Device have been numerically simulated for certain predefined model fast ion distribution functions.

12.
Rev Sci Instrum ; 79(10): 10F312, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044625

RESUMO

Measurements of energy- and time-resolved neutral hydrogen and helium fluxes from an impurity pellet ablation cloud, referred to as pellet charge exchange or PCX experiments, can be used to study local fast ion energy distributions in fusion plasmas. The estimation of the local distribution function f(i)(E) of fast ions entering the cloud requires knowledge of both the fraction F(0)(E) of incident ions exiting the cloud as neutral atoms and the attenuation factor A(E,rho) describing the loss of fast atoms in the plasma. Determination of A(E,rho), in turn, requires the total stopping cross section sigma(loss) of neutral atoms in the plasma and the Jacobian reflecting the measurement geometry and the magnetic surface shape. The obtained functions F(0)(E) and A(E,rho) enter multiplicatively into the probability density for escaping neutral particle kinetic energy. A general calculation scheme has been developed and realized as a FORTRAN code, which is to be applied for the calculation of f(i)(E) from PCX experimental results obtained with low-Z impurity pellets.

13.
Rev Sci Instrum ; 79(10): 10F541, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044683

RESUMO

In the Large Helical Device (LHD), various spectroscopic diagnostics have been applied to study the ablation process of an advanced impurity pellet, tracer-encapsulated solid pellet (TESPEL). The total light emission from the ablation cloud of TESPEL is measured by photomultipliers equipped with individual interference filters, which provide information about the TESPEL penetration depth. The spectra emitted from the TESPEL ablation cloud are measured with a 250 mm Czerny-Turner spectrometer equipped with an intensified charge coupled device detector, which is operated in the fast kinetic mode. This diagnostic allows us to evaluate the temporal evolution of the electron density in the TESPEL ablation cloud. In order to gain information about the spatial distribution of the cloud parameters, a nine image optical system that can simultaneously acquire nine images of the TESPEL ablation cloud has recently been developed. Several images of the TESPEL ablation cloud in different spectral domains will give us the spatial distribution of the TESPEL cloud density and temperature.

14.
J Phys Condens Matter ; 20(20): 204142, 2008 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-21694271

RESUMO

A magnetic fluid microdevice using Diptera insect wings is proposed and constructed. The magnetic fluid device is composed of insect wings, a small permanent magnet, coil, and kerosene-based magnetic fluid. First, the structural properties of insect wings are studied through measurements of certain morphological parameters. Secondly, the novel type of microwind energy converter is constructed. Thirdly, the power generation characteristics of the magnetic fluid microdevice using insect wings are examined. It is found that the output power is roughly proportional to the cube of the airflow velocity.

15.
Opt Express ; 15(13): 8135-45, 2007 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-19547140

RESUMO

We describe a highly sensitive, real-time method of detecting small particles in a fluid flow by self-mixing laser Doppler measurement with a laser-diode-pumped, thin-slice solid-state laser with extremely high optical sensitivity. Asymmetric power spectra of the laser output modulated by the re-injected scattered light from the small particles moving in a dilute sample-flow, through a small-diameter glass pipe, were observed. The observed power spectra are shown to reflect the velocity distribution of the fluid flow, which obeys Poiseuille's law. Quick measurements of flow rate and kinetic viscosities of water-glycerol mixtures were also performed successfully. Measurable low-concentration limits for 262-nm polystyrene latex spheres and 3-mum red blood cells in a fluid flow were below 1 and 10 ppm, respectively, in the present self-mixing laser Doppler velocimeter system.

16.
J Phys Chem A ; 110(15): 4953-7, 2006 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-16610812

RESUMO

Broadband dielectric measurements for blends of poly(vinyl pyrrolidone) (PVP) and ethylene glycol oligomer (EGO) from 0 to 40 wt % PVP were carried out at 25 degrees C in the frequency range from 20 Hz to 20 GHz. The EGOs used in this study were ethylene glycol (EG), diethylene glycol (2EG), and PEG400 (MW = 400). For the PVP-EG, -2EG, and -PEG400 blends, relaxation processes caused by the motion of EGO in the GHz range and the micro-Brownian motion of the PVP chain at 10 kHz-1 MHz were observed. Although the PVP-EGO blend is miscible, relaxation processes caused by the molecular motion of EGO and the local chain motion of PVP were observed individually. The relaxation time of the local chain motion of PVP showed a strong PVP concentration dependence and a solvent viscosity dependence, which are similar to those reported so far for the solutions in nonpolar solvents.

17.
J Chem Phys ; 124(4): 044901, 2006 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-16460206

RESUMO

We performed broadband dielectric measurements of a polyethyleneglycol-water mixture in the frequency range between 10 GHz and 1 microHz and the temperature range between 300 and 133 K. One relaxation process is observed throughout the whole temperature range. The temperature dependence of the relaxation time clearly obeys the Vogel-Fulcher law above 183 K, and the Arrhenius law below 183 K. This observed relaxation process is the secondary process, and the primary process related to the glass transition is masked by the low-frequency ionic contribution below 183 K. The glass transition concerned with the masked primary process leads to the Vogel-Fulcher to Arrhenius transition of the secondary process.

18.
Acta Neurol Scand ; 112(5): 327-34, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16218916

RESUMO

OBJECTIVE: The present study was performed to compare the distributions of three-repeat (3R) and four-repeat (4R) neurofibrillary tangles (NFT) with those of pretangles (p-NFT), intracellular NFT (i-NFT), and extracellular NFT (e-NFT) in the hippocampus of Alzheimer's disease brains. METHODS: NFT labeling was performed using anti-tau antibodies: pSer262 for p-NFT, pSer422 for i-NFT, AT8 for e-NFT, RD3 for 3R, and RD4 for 4R tau, and Gallyas impregnation for the NFT population. RD4- and pSer422-positive NFT were detected predominantly in sectors from CA2 to CA4, while RD3- and pSer262-positive NFT were predominantly present in CA1, the entorhinal cortex, and the subiculum. The tau epitope recognized by pSer262 belongs to 4R tau but it showed a strong correlation with RD3- and AT8-positive NFT. CONCLUSIONS: Sectors CA2-CA4 showed predominantly 4R-NFT containing the pSer422 epitope. pSer262 may detect the process of transformation from p-NFT to i-NFT, and e-NFT consisted predominantly of 3R tau.


Assuntos
Doença de Alzheimer/patologia , Sítios de Ligação/genética , Hipocampo/patologia , Microtúbulos/genética , Emaranhados Neurofibrilares/patologia , Neurofibrilas/genética , Sequências Repetitivas de Ácido Nucleico/genética , Adulto , Idoso , Córtex Entorrinal/patologia , Feminino , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/genética , Estatística como Assunto , Repetições de Trinucleotídeos/genética , Proteínas tau/genética
19.
Phys Rev Lett ; 92(5): 055002, 2004 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-14995316

RESUMO

Evidence for a reduction of heat transport inside the magnetic island O point is observed from the propagation of a cold pulse produced by a tracer encapsulated solid pellet in the Large Helical Device. A small peak and slow propagation of the cold pulse are observed inside the island. A significant result is that electron heat diffusivity inside the island is estimated to be 0.2 m(2)/s which is smaller than that outside the island by an order of magnitude.

20.
Acta Neuropathol ; 103(5): 521-5, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11935270

RESUMO

This study concerns an autopsy case of motor neuron disease with dementia (MND-D) that exhibited unusual clinical and neuropathological findings. The patient was a Japanese man without any relevant family history who was 60 years old at the time of death. His clinical manifestation included character change at the age of 54, followed by frozen gait, dysarthria and bradykinesia and he was diagnosed with Parkinson's disease. He gradually developed spastic paresis and died of respiratory failure 6 years after onset of the illness. Neuropathological examinations showed prominent degeneration in the striatonigral and pallidoluysian systems in addition to the neuronal loss and microvacuolation in the second to third layers of the frontal and temporal cortex, the involvement of the upper and lower motor neuron systems and the presence of ubiquitinated neuronal inclusions. To our knowledge, five cases of motor neuron disease (MND) combined with pallido-nigro-luysian atrophy (PNLA) have been reported previously, but the present case is the first report of MND-D combined with the degeneration of the striatonigral and pallidoluysian systems. Such an association may represent more than a coincidental occurrence, and it suggests that MND-D is not simply a disease of the motor neuron system but a multisystem degeneration.


Assuntos
Demência/complicações , Demência/patologia , Globo Pálido/patologia , Doença dos Neurônios Motores/complicações , Doença dos Neurônios Motores/patologia , Degeneração Estriatonigral/complicações , Degeneração Estriatonigral/patologia , Núcleo Subtalâmico/patologia , Demência/fisiopatologia , Giro Denteado/patologia , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Globo Pálido/fisiopatologia , Humanos , Corpos de Inclusão/patologia , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/fisiopatologia , Neurônios/patologia , Tratos Piramidais/patologia , Tratos Piramidais/fisiopatologia , Degeneração Estriatonigral/fisiopatologia , Substância Negra/patologia , Núcleo Subtalâmico/fisiopatologia , Ubiquitina/metabolismo
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