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1.
J Equine Sci ; 32(3): 73-80, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34539208

RESUMEN

The measurement of various body dimensions of horses plays a significant role in quality improvement, genetic breeding, health, and soundness. There has been significant advancement in the technology for acquiring stereoscopic images with a three-dimensional (3D) scanner. This study aimed to validate the accuracy of body measurements obtained from stereoscopic images taken with a 3D scanner. We manually took the following body measurements for 8 riding horses: height at the withers, height at the back, height at the croup, chest depth, width of the chest, width of the croup, width of the waist, girth circumference, cannon circumference, and body length. Using a versatile tablet-type 3D scanning device, we captured a 3D image of each horse. Relative errors varied from -1.37% to 6.25%. The correlation coefficient between manual and 3D measurements was significant for all body measurements (P<0.01) except for width of the waist and cannon circumference. The low accuracy of cannon circumference (r=0.248) was due to effect of hair. A simple regression analysis of all body measurements revealed a strong correlation (P<0.001, R2=0.9994, root-mean-square error [RMSE]=1.522). Notable advantages of this methodology include high accuracy, good operability, non-contact, high versatility, and low cost. Further studies are required for the establishment of an accurate measurement methodology that can scan the whole body in a shorter time.

2.
Appl Opt ; 53(29): 6900-12, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25508778

RESUMEN

A space-resolved vacuum ultraviolet (VUV) spectroscopy using a 3 m normal incidence spectrometer has been developed to measure the impurity profile in the edge ergodic layer composed of stochastic magnetic field by which the edge plasma in the large helical device (LHD) is uniquely characterized. It vertically measures the spatial profile of VUV lines emitted from impurities in the wavelength range of 300-3200 Å. The wavelength interval, Δλ, which can be measured in a single discharge, is about 37 Å. A spectral resolution of 0.153 Å, which results from an entrance slit width of the spectrometer of 20 µm, is adopted. The vertical observation range, ΔZ, can be switched by taking a convex mirror in and out, which enables both the edge profile measurement focused on the ergodic layer and the full profile measurement covering an entire vertical size of the LHD plasma, e.g., 165 ≤ ΔZ ≤ 200 mm and 1000 ≤ ΔZ ≤ 1250 mm for the R(ax)=3.6 m configuration, respectively, which shows a slight wavelength dependence. Precise calibrations on the line dispersion, spectral resolution, vertical range of the observable region, and the spatial resolution have been performed with a unique method. As a preliminary result, the ion temperature profile is obtained for CIV at 1548.20 Å in the second order (denoted as 1548.20 × 2 Å) in high-density helium discharges in addition to the emission profile with a time resolution of 100 ms in a multitrack CCD operation mode. The poloidal flow in the ergodic layer based on the Doppler-shift measurement of CIV at 1548.20 × 2 Å is also observed in high-density hydrogen discharges.

3.
Appl Opt ; 53(29): 6900-12, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25481926

RESUMEN

A space-resolved vacuum ultraviolet (VUV) spectroscopy using a 3 m normal incidence spectrometer has been developed to measure the impurity profile in the edge ergodic layer composed of stochastic magnetic field by which the edge plasma in the large helical device (LHD) is uniquely characterized. It vertically measures the spatial profile of VUV lines emitted from impurities in the wavelength range of 300-3200 Å. The wavelength interval, Δλ, which can be measured in a single discharge, is about 37 Å. A spectral resolution of 0.153 Å, which results from an entrance slit width of the spectrometer of 20 µm, is adopted. The vertical observation range, ΔZ, can be switched by taking a convex mirror in and out, which enables both the edge profile measurement focused on the ergodic layer and the full profile measurement covering an entire vertical size of the LHD plasma, e.g., 165 ≤ ΔZ ≤ 200 mm and 1000 ≤ ΔZ ≤ 1250 mm for the R(ax)=3.6 m configuration, respectively, which shows a slight wavelength dependence. Precise calibrations on the line dispersion, spectral resolution, vertical range of the observable region, and the spatial resolution have been performed with a unique method. As a preliminary result, the ion temperature profile is obtained for CIV at 1548.20 Å in the second order (denoted as 1548.20 × 2 Å) in high-density helium discharges in addition to the emission profile with a time resolution of 100 ms in a multitrack CCD operation mode. The poloidal flow in the ergodic layer based on the Doppler-shift measurement of CIV at 1548.20 × 2 Å is also observed in high-density hydrogen discharges.

4.
Anim Sci J ; 94(1): e13863, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37560807

RESUMEN

Respiratory disease in calves is one of the most prominent diseases affecting their growth. The early and accurate detection of calf disease on the farm brings proper growth of calves. The objective of this study was to compare the daily and hourly behavioral time of diseased calves with the other calves in same pen (pen-mates) for 7 days prior to the diagnosis day. The calves (from 14 to 20 heads) were reared in a group. Day 0 was defined as the day of diagnosis. The number of diseased calves was 30 in the present experiment. The lying and eating behavior of calves were observed at 10-min intervals. The diseased calves have significantly (P < 0.01) shorter eating times than the pen-mates on the diagnosis day. The longest hourly time of the eating was in the period between 08:00 and 09:00, and shortest lying time was in the period between 09:00 and 10:00. Diseased calves had significantly (P < 0.05) longer daily lying time and shorter daily eating time than the pen-mates almost for the 7 days prior to the diagnosis day. Even though the daily behavioral time was different, the difference of behavioral time in successive hour periods was limited.


Asunto(s)
Enfermedades de los Bovinos , Enfermedades Respiratorias , Animales , Bovinos , Conducta Animal , Conducta Alimentaria , Peso Corporal , Enfermedades Respiratorias/veterinaria , Destete , Enfermedades de los Bovinos/diagnóstico
5.
Respir Res ; 13: 55, 2012 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-22731784

RESUMEN

BACKGROUND: The mechanisms underlying the association between smoking and mucus overproduction remain unknown. Because of its involvement in other airway diseases, such as asthma, we hypothesized that Ca²âº-activated Cl⁻ channel 1 (CLCA1) was associated with overproduction of mucus in the airways of smokers and COPD patients. METHODS: Using real-time quantitative PCR analyses, we compared the CLCA1 mRNA expression levels in induced-sputum cells from COPD patients (n = 20), smokers without COPD (n = 5), and non-smokers (n =13). We also examined the relationship between CLCA1 protein expression and mucus production in lung airway epithelia of COPD patients (n = 6), smokers without COPD (n = 7), and non-smokers (n = 7). RESULTS: CLCA1 mRNA expression was significantly up-regulated in the induced-sputum cells of COPD patients compared with cells of non-smokers (p = 0.02), but there was no significant difference compared with cells of smokers without COPD. Using immunostaining with an anti-CLCA1 antibody, semi-quantitative image analyses of airway epithelium demonstrated significantly increased CLCA1 expression in smokers without COPD (p = 0.02) and in COPD patients (p = 0.002) compared with non-smokers. There were significant negative correlations between CLCA1 protein expression and FEV1/FVC (r = -0.57, p = 0.01) and %predicted FEV1 (r = -0.56, p = 0.01). PAS staining for mucus showed that there was a significant positive correlation between CLCA1 protein expression and mucus production (r = 0.67, p = 0.001). These markers were significantly increased in smokers without COPD (p = 0.04) and in COPD patients (p = 0.003) compared with non-smokers (non-smokers < smokers ≤ COPD). CONCLUSIONS: CLCA1 expression is significantly related to mucus production in the airway epithelia of smokers and COPD patients, and may contribute to the development and pathogenesis of COPD by inducing mucus production.


Asunto(s)
Canales de Cloruro/metabolismo , Células Epiteliales/metabolismo , Pulmón/metabolismo , Moco/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Mucosa Respiratoria/metabolismo , Fumar/efectos adversos , Adulto , Anciano , Estudios de Casos y Controles , Canales de Cloruro/genética , Femenino , Volumen Espiratorio Forzado , Humanos , Inmunohistoquímica , Subunidad alfa1 del Receptor de Interleucina-13 , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Mucina 5AC/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Interleucina-13/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esputo/citología , Regulación hacia Arriba , Capacidad Vital
6.
Rev Sci Instrum ; 93(12): 123501, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36586905

RESUMEN

Two pairs of space-resolved extreme ultraviolet (EUV) spectrometers working at 5-138 Å with different vertical observation ranges of -7 ≤ Z ≤ 19 and -18 ≤ Z ≤ 8 cm have been newly developed to observe the radial profile of impurity line emissions and to study the transport of high-Z impurity ions intrinsically existing in EAST tokamak plasmas. Both spectrometers are equipped with a complementary metal-oxide semiconductor (CMOS) detector (Andor Marana-X 4.2B-6, Oxford Instruments) with sensitive area of 13.3 × 13.3 mm2 and number of pixels equal to 2048 × 2048 (6.5 × 6.5 µm2/pixels). Compared to the currently operating space-resolved EUV spectrometers with a charge-coupled detector (CCD: 1024 × 255 pixels, 26 × 26 µm2) working at 30-520 Å, this spectrometer's performance was substantially improved by using the CMOS detector. First, the spectral resolution measured at full width at half maximum was improved in the whole wavelength range, e.g., Δλ1/2_CMOS = 0.092 Å and Δλ1/2_CCD = 0.124 Å at C VI 33.73 Å and Δλ1/2_CMOS = 0.104 Å and Δλ1/2_CCD = 0.228 Å at Mo XXXI 115.999 Å, thus enabling a more accurate analysis of spectra with complicated structure such as tungsten unresolved transition array in the range 45-65 Å. Second, the temporal resolution was largely improved due to the high-speed data acquisition system of the CMOS detector, e.g., Δt_CMOS = 15 ms/frame and Δt_CCD = 200 ms/frame at routine operation in the radial profile measurement. Third, signal saturation issues that occurred when using the old CCD sensor during impurity accumulation now disappeared entirely using the CMOS detector due to lower exposure time at high readout rates, which largely improved the observation performance in similar impurity burst events. The above-mentioned performance improvements of the space-resolved EUV spectrometer led to a rapid change in the W XXXIII (52.22 Å) radial profile during a single cycle of low-frequency sawtooth oscillation with fst = 5-6 Hz at a sufficient detector count rate.

7.
Anim Sci J ; 90(2): 205-213, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30554472

RESUMEN

The present study examined the effects of substituting kraft pulp (KP) with corn silage (CS) on dry matter intake (DMI), ruminal mat and rumen fermentation characteristics, and rumination. Four non-lactating, rumen-cannulated Holstein cows were fed a CS diet comprising 36% grass silage (GS) and 64% CS or a KP diet comprising 36% GS, 57% KP, and 7% soybean meal. DMI was significantly lower in cows fed the KP diet than in those fed the CS diet (p < 0.05), whereas rumination time did not significantly differ between the treatments. Dry matter content in the rumen immediately before and 3 h after feeding was significantly higher in cows fed the KP diet than in those fed the CS diet (p < 0.05). The consistency and thickness of the ruminal mat did not significantly differ between the treatments. The ruminal mean retention time of feed particles tended to be longer in cows fed the KP diet than in those fed the CS diet (p < 0.10). The ruminal digestion rate of KP was comparable to that of GS and CS. Because ruminal mat was formed and rumination was stimulated, KP was considered to have the equivalent physical effectiveness as CS.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Bovinos/metabolismo , Bovinos/fisiología , Dieta/veterinaria , Digestión , Ingestión de Alimentos , Rumen/metabolismo , Rumen/fisiología , Rumiación Digestiva , Ensilaje , Madera , Zea mays , Animales , Femenino , Lactancia , Factores de Tiempo
8.
Anim Sci J ; 89(2): 494-497, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28994168

RESUMEN

We compared the hair cortisol levels of lactating dairy cows in a cold- and a warm-temperate region out of four climatic zones in Japan. We simultaneously investigated the effects of calving number, lactation period and month of hair sampling. Hair of nine Holstein lactating cows chosen from each region (i.e. 18 cows per sampling) was sampled in March, June, September and December. Number of calvings (1, 2, ≥3) and lactation duration (early: <100, middle: 101-200, and late: >201 days) were balanced between regions. Cortisol was extracted from hair by methanol, and its level was determined with a cortisol immunoassay kit. A multi-way analysis of variance revealed that the effects of month of hair sampling (P < 0.001) and its combination with region (P < 0.05) were significant. In a multiple comparison test, significant differences (P < 0.01) in hair cortisol level (pg/mg of hair) were found between June (13.0 ± 1.0) and the other 3 months, and between September (1.6 ± 0.2) and December (4.5 ± 0.3). The rise in cortisol level from March to June was more intense in the cold-temperate region. These results demonstrate the necessity of considering seasonal variations in each climatic region when we use hair cortisol level as an indicator of stress.


Asunto(s)
Bovinos/metabolismo , Bovinos/fisiología , Exposición a Riesgos Ambientales , Cabello/metabolismo , Hidrocortisona/metabolismo , Lactancia/metabolismo , Temperatura , Animales , Clima , Frío , Femenino , Japón , Estaciones del Año
9.
Rev Sci Instrum ; 78(2): 023501, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17578107

RESUMEN

A flat-field extreme ultraviolet (EUV) spectrometer with a varied line spacing groove grating (1200 grooves/mm at grating center) has been developed to study the emission spectra from highly ionized medium Z impurities in large helical device (LHD). It covers a wavelength range of 50-500 A using a mechanically ruled grating, which was later replaced by a newly developed laminar-type holographic grating for comparative studies. Differences in spectral resolution, intensities of higher order spectra, and sensitivities of the spectrometer were studied between the two gratings by observing the emission spectra of LHD plasmas. Although the achieved resolution was alike between them, i.e., deltalambda approximately 0.24 A at 200 A, the holographic grating was much superior in suppressing the higher order light than the ruled grating. The relative sensitivity between the two gratings was evaluated using continuum radiation from LHD plasmas. As a result, it was found that the holographic grating has a flat response in the full wavelength range, but the sensitivity of the ruled grating drops sharply below 200 A. A new technique for the absolute calibration of the EUV holographic grating spectrometer was tried by combining the continuum radiation with a branching ratio of C IV lines (3p-3s: 5800 A/3p-2s: 312 A), and an accurate absolute sensitivity has been successfully obtained.

10.
Rev Sci Instrum ; 86(12): 123509, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26724029

RESUMEN

A flat-field extreme ultraviolet (EUV) spectrometer working in the 20-500 Å wavelength range with fast time response has been newly developed to measure line emissions from highly ionized tungsten in the Experimental Advanced Superconducting Tokamak (EAST) with a tungsten divertor, while the monitoring of light and medium impurities is also an aim in the present development. A flat-field focal plane for spectral image detection is made by a laminar-type varied-line-spacing concave holographic grating with an angle of incidence of 87°. A back-illuminated charge-coupled device (CCD) with a total size of 26.6 × 6.6 mm(2) and pixel numbers of 1024 × 255 (26 × 26 µm(2)/pixel) is used for recording the focal image of spectral lines. An excellent spectral resolution of Δλ0 = 3-4 pixels, where Δλ0 is defined as full width at the foot position of a spectral line, is obtained at the 80-400 Å wavelength range after careful adjustment of the grating and CCD positions. The high signal readout rate of the CCD can improve the temporal resolution of time-resolved spectra when the CCD is operated in the full vertical binning mode. It is usually operated at 5 ms per frame. If the vertical size of the CCD is reduced with a narrow slit, the time response becomes faster. The high-time response in the spectral measurement therefore makes possible a variety of spectroscopic studies, e.g., impurity behavior in long pulse discharges with edge-localized mode bursts. An absolute intensity calibration of the EUV spectrometer is also carried out with a technique using the EUV bremsstrahlung continuum at 20-150 Å for quantitative data analysis. Thus, the high-time resolution tungsten spectra have been successfully observed with good spectral resolution using the present EUV spectrometer system. Typical tungsten spectra in the EUV wavelength range observed from EAST discharges are presented with absolute intensity and spectral identification.

11.
Rev Sci Instrum ; 85(4): 043511, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24784611

RESUMEN

A flat-field space-resolved extreme ultraviolet (EUV) spectrometer system working in wavelength range of 10-130 Å has been constructed in the Large Helical Device (LHD) for profile measurements of bremsstrahlung continuum and line emissions of heavy impurities in the central column of plasmas, which are aimed at studies on Zeff and impurity transport, respectively. Until now, a large amount of spike noise caused by neutral particles with high energies (≤180 keV) originating in neutral beam injection has been observed in EUV spectroscopy on LHD. The new system has been developed with an aim to delete such a spike noise from the signal by installing a thin filter which can block the high-energy neutral particles entering the EUV spectrometer. Three filters of 11 µm thick beryllium (Be), 3.3 µm thick polypropylene (PP), and 0.5 µm thick polyethylene terephthalate (PET: polyester) have been examined to eliminate the spike noise. Although the 11 µm Be and 3.3 µm PP filters can fully delete the spike noise in wavelength range of λ ≤ 20 Å, the signal intensity is also reduced. The 0.5 µm PET filter, on the other hand, can maintain sufficient signal intensity for the measurement and the spike noise remained in the signal is acceptable. As a result, the bremsstrahlung profile is successfully measured without noise at 20 Å even in low-density discharges, e.g., 2.9 × 10(13) cm(-3), when the 0.5 µm PET filter is used. The iron n = 3-2 Lα transition array consisting of FeXVII to FeXXIV is also excellently observed with their radial profiles in wavelength range of 10-18 Å. Each transition in the Lα array can be accurately identified with its radial profile. As a typical example of the method a spectral line at 17.62 Å is identified as FeXVIII transition. Results on absolute intensity calibration of the spectrometer system, pulse height and noise count analyses of the spike noise between holographic and ruled gratings and wavelength response of the used filters are also presented with performance of the present spectrometer system.

12.
J Mol Neurosci ; 52(4): 531-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24005768

RESUMEN

Age-related decrease of testosterone levels in blood and brain is believed to be associated with neurodegenerative diseases such as Alzheimer's disease. However, the effect of testosterone on brain function is not well understood. Therefore, we investigated the impact of testosterone deprivation on mitochondrial gene expression in the brain of male gonadectomized (GDX) rats. We found that peripheral castration led to testosterone deficiency in the brain and caused a significant reduction in protein and mRNA expression of genes encoded by mitochondrial DNA, namely NADPH dehydrogenase subunit 1, subunit 4, cytochrome b, and cytochrome c oxidase subunit 1 and subunit 3 in the hippocampus. In addition, gene expression of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α), which is a master regulator of mitochondrial biogenesis, and its downstream transcriptional factors, nuclear respiratory factors 1 and 2 and mitochondrial transcription factors A and B2, were also decreased in the hippocampus of GDX rats. These reductions in the expression of mitochondrial gene and transcriptional coactivators and factors were recovered by androgen replacement. These findings indicate that androgen plays an important role in mitochondrial gene expression in the hippocampus.


Asunto(s)
Corteza Cerebral/fisiología , Genes Mitocondriales/genética , Hipocampo/fisiología , Testosterona/deficiencia , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Envejecimiento/fisiología , Animales , Encéfalo/fisiología , Citocromos b/genética , Citocromos b/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Humanos , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/fisiología , NADPH Deshidrogenasa/genética , NADPH Deshidrogenasa/metabolismo , Orquiectomía , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Ratas , Ratas Sprague-Dawley , Testosterona/farmacología
13.
Rev Sci Instrum ; 85(11): 11E426, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430333

RESUMEN

A space-resolved grazing-incidence flat-field extreme ultraviolet (EUV) spectrometer has been developed in the HL-2A tokamak to measure vertical impurity emission profiles with simultaneous spectral, temporal, and spatial resolution. The spectrometer working in the wavelength range of 30-500 Å has been equipped with a gold-coated varied-line-spacing holographic grating with curvature of 5606 mm and a back illuminated charge-coupled device with size of 6.6 × 26.6 mm(2) (255 × 1024 pixels). A lower half of the HL-2A plasma with averaged minor radius of 40 cm is observed when the spectrometer with horizontal dispersion is placed at a distance of 7.5 m away from the plasma center. An excellent spatial resolution of 12 mm is achieved when a space-resolved slit with vertical width of 0.5 mm is adopted. The radial profiles of intrinsic impurities in several ionization stages have been measured with high throughput and extremely low stray light.

14.
Anim Sci J ; 84(12): 798-801, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23638759

RESUMEN

After the disastrous incident of the Fukushima Daiichi Nuclear Power Station, various agricultural, livestock and fishery products have been inspected for radioactive contamination with cesium in Japan. In this study, radioactive cesium was measured in various edible parts of cattle to verify the current inspection method for cattle, in which the neck tissues are generally used as samples. Radioactive cesium concentration in the short plate, diaphragm, liver, lung, omasum, abomasum and small intestine were lower and sirloin, tenderloin, top round meat and tongue were higher than that in the neck. There was no significant difference between the other organs (heart, kidney, lumen and reticulum) and the neck. Ninety-five percent upper tolerance limits of the relative concentration to the neck were 1.88 for sirloin, 1.74 for tenderloin, 1.87 for top round and 1.45 for tongue. These results suggest that a safety factor of 2 is recommended for the radioactivity inspection of cattle to prevent a marketing of meat with higher cesium than the legal limit. Re-inspection should be conducted using another part of muscle, for example, top round, when suspicious levels of 50-100 Bq/kg are detected in the neck.


Asunto(s)
Radioisótopos de Cesio/análisis , Análisis de los Alimentos/métodos , Contaminación Radiactiva de Alimentos/análisis , Inspección de Alimentos/métodos , Carne/análisis , Acenaftenos , Animales , Bovinos , Contaminación Radiactiva de Alimentos/prevención & control , Accidente Nuclear de Fukushima
15.
Rev Sci Instrum ; 83(4): 043503, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22559532

RESUMEN

A space-resolved extreme ultraviolet (EUV) spectrometer working in wavelength range of 50-500 Å has been developed to measure two-dimensional distribution of impurity spectral lines emitted from edge plasma of Large Helical Device (LHD), in which the magnetic field is formed by stochastic magnetic field with three-dimensional structure called ergodic layer. The two-dimensional measurement of edge impurity line emissions is carried out by scanning horizontally the observation chord of the space-resolved EUV spectrometer during single LHD discharge. Images of CIV (312.4 Å) and HeII (303.78 Å) are presented as the first result. The results are compared with ones calculated from the edge chord length in the ergodic layer of LHD plasma.

16.
Rev Sci Instrum ; 83(10): 10D509, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23126852

RESUMEN

Spectra measured by an extreme ultraviolet (EUV) spectrometer frequently suffer large spike noise when Large Helical Device is operated in low-density range (≤ 3 × 10(13) cm(-3)) with neutral beam injection (NBI). The spike noise completely disappears in electron cyclotron heating discharges. In order to examine the effect of NBI, a carbon filter with thickness of 150 nm was installed in the EUV spectrometer. As a result, the spike noise was reduced by an order of magnitude. It is experimentally verified that the spike noise is caused by escaping high-energy neutral particles resulting from the circulating high-energy hydrogen ions borne from NBI.

17.
Rev Sci Instrum ; 83(10): 10E509, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23127016

RESUMEN

Vertical profile of neon line emissions in 30-650 Å wavelength range has been observed in horizontally elongated plasma cross section of Large Helical Device (LHD). Intensity ratio between the neon line emissions is studied to measure the radial profile of electron temperature in the edge stochastic magnetic field layer of LHD. The edge temperature profile successfully obtained from the line ratio of NeVIII 2s-3p to 2p-3s transitions is compared with the simulation based on three-dimensional edge transport code. The result shows a reasonably good agreement with the edge temperature profile analyzed from atomic data and analysis structure code. The electron temperature at last closed flux surface measured from the intensity ratio is also in good agreement with that measured from Thomson scattering.

18.
Rev Sci Instrum ; 83(10): 10D507, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23126850

RESUMEN

A grazing-incidence flat-field extreme ultraviolet (EUV) spectrometer has been newly developed in HL-2A tokamak. Typical spectral lines are observed from intrinsic impurities of carbon, oxygen, iron, and extrinsic impurity of helium in the wavelength range of 20 Å-500 Å. Bremsstrahlung continuum is measured at different electron densities of HL-2A discharges to calibrate absolute sensitivity of the EUV spectrometer system and to measure effective ionic charge, Z(eff). The sensitivity of a vacuum ultraviolet (VUV) spectrometer system is also absolutely calibrated in overlapped wavelength range of 300 Å-500 Å by comparing the intensity between VUV and EUV line emissions.

19.
Rev Sci Instrum ; 82(11): 113102, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22128961

RESUMEN

A precise absolute intensity calibration of a flat-field space-resolved extreme ultraviolet (EUV) spectrometer working in wavelength range of 60-400 Å is carried out using a new calibration technique based on radial profile measurement of the bremsstrahlung continuum in Large Helical Device. A peaked vertical profile of the EUV bremsstrahlung continuum has been successfully observed in high-density plasmas (n(e) ≥ 10(14) cm(-3)) with hydrogen ice pellet injection. The absolute calibration can be done by comparing the EUV bremsstrahlung profile with the visible bremsstrahlung profile of which the absolute value has been already calibrated using a standard lamp. The line-integrated profile of measured visible bremsstrahlung continuum is firstly converted into the local emissivity profile by considering a magnetic surface distortion due to the plasma pressure, and the local emissivity profile of EUV bremsstrahlung is secondly calculated by taking into account the electron temperature profile and free-free gaunt factor. The line-integrated profile of the EUV bremsstrahlung continuum is finally calculated from the local emissivity profile in order to compare with measured EUV bremsstrahlung profile. The absolute intensity calibration can be done by comparing measured and calculated EUV bremsstrahlung profiles. The calibration factor is thus obtained as a function of wavelength with excellent accuracy. It is also found in the profile analysis that the grating reflectivity of EUV emissions is constant along the direction perpendicular to the wavelength dispersion. Uncertainties on the calibration factor determined with the present method are discussed including charge-coupled device operation modes.

20.
Rev Sci Instrum ; 81(3): 033107, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20370161

RESUMEN

A space-resolved extreme ultraviolet (EUV) spectrometer working in 60-400 A range has been developed to observe impurity emission profiles in core and edge plasmas of Large Helical Device (LHD). A flat focus is made for plane surface detector by using a varied line spacing holographic grating with an angle of incidence of 87 degrees. An excellent spectral resolution of 0.22 A at 200 A is then obtained after careful adjustment of the optical components. In the profile measurement of the LHD plasmas, the toroidal resolution is important as well as the radial resolution because the magnetic surfaces of LHD quickly change when the observation chord is tilted at a slightly different toroidal location. Horizontal dispersion is therefore selected for the present spectrometer. As a result, the toroidal resolution of 75 mm is achieved at the plasma position. An enough radial resolution of 10 mm is also obtained at spatial-resolution slit width of 0.2 mm. In order to measure the full radial profile of LHD plasmas the spectrometer is placed at a distance of approximately 9200 mm away from the plasma center and a backilluminated charge-coupled device with a size of 6.6x26.6 mm(2) is set vertical to the horizontal dispersion. Half of the LHD plasma, i.e., approximately 50 cm, can be measured along the vertical direction at horizontally elongated plasma cross section. A full vertical profile can be obtained by changing the vertical angle of the EUV spectrometer. As an example the full vertical profile of edge C IV (312.4 A) emission is presented. A wavelength interval of 35-65 A can be simultaneously observed, which varies according to the wavelength to be measured. A local emission profile of Fe XX (132.67 A) is also presented after Abel inversion as a typical example of the core EUV emission. Finally, the EUV spectrometer is absolutely calibrated using EUV bremsstrahlung continuum profile in comparison with absolute values of visible bremsstrahlung continuum profile because the bremsstrahlung continuum can be easily detected in high-density discharges of LHD.

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