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1.
J Synchrotron Radiat ; 21(Pt 1): 268-72, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24365948

RESUMEN

The newly installed BL28XU beamline at SPring-8 is dedicated to in situ structural and electronic analysis of rechargeable batteries. It supports the time range (1 ms to 100 s) and spatial range (1 µm to 1 mm) needed for battery analysis. Electrochemical apparatus for battery charging and discharging are available in experimental hutches and in a preparation room. Battery analysis can be carried out efficiently and effectively using X-ray diffraction, X-ray absorption fine-structure analysis and hard X-ray photoelectron spectroscopy. Here, the design and performance of the beamline are described, and preliminary results are presented.

2.
J Synchrotron Radiat ; 20(Pt 2): 266-71, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23412483

RESUMEN

An X-ray Raman spectrometer for studies of local structures in minerals is discussed. Contrary to widely adopted back-scattering spectrometers using ≤10 keV X-rays, a spectrometer utilizing ~20 keV X-rays and a bent Laue analyzer is proposed. The 20 keV photons penetrate mineral samples much more deeply than 10 keV photons, so that high intensity is obtained owing to an enhancement of the scattering volume. Furthermore, a bent Laue analyzer provides a wide band-pass and a high reflectivity, leading to a much enhanced integrated intensity. A prototype spectrometer has been constructed and performance tests carried out. The oxygen K-edge in SiO(2) glass and crystal (α-quartz) has been measured with energy resolutions of 4 eV (EXAFS mode) and 1.3 eV (XANES mode). Unlike methods previously adopted, it is proposed to determine the pre-edge curve based on a theoretical Compton profile and a Monte Carlo multiple-scattering simulation before extracting EXAFS features. It is shown that the obtained EXAFS features are reproduced fairly well by a cluster model with a minimal set of fitting parameters. The spectrometer and the data processing proposed here are readily applicable to high-pressure studies.

3.
Nano Lett ; 10(2): 414-9, 2010 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-20041706

RESUMEN

The limit to which the phase change memory material Ge(2)Sb(2)Te(5) can be scaled toward the smallest possible memory cell is investigated using structural and optical methodologies. The encapsulation material surrounding the Ge(2)Sb(2)Te(5) has an increasingly dominant effect on the material's ability to change phase, and a profound increase in the crystallization temperature is observed when the Ge(2)Sb(2)Te(5) layer is less than 6 nm thick. We have found that the increased crystallization temperature originates from compressive stress exerted from the encapsulation material. By minimizing the stress, we have maintained the bulk crystallization temperature in Ge(2)Sb(2)Te(5) films just 2 nm thick.

4.
Sci Total Environ ; 403(1-3): 230-4, 2008 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-18593638

RESUMEN

Pb-LIII edge XANES spectra of atmospheric particles are directly obtained by fluorescent XAFS spectroscopy using a 19-element solid state detector (SSD). Particulate sample was collected on a quartz fiber filter using a high-volume air sampler, and the filter was cut into small pieces (25x25 mm). Then, surface layer of the filter piece was scaled and accumulated in order to enhance the particle density per filter unit. Use of 10 pieces of the surface layer enables the measurement of Pb-LIII edge XANES spectra on beamline BL01B1 at SPring-8, Hyogo, Japan. The shape of the Pb-LIII edge XANES spectra of the particulate sample is similar to the shapes of the spectra for PbS, PbCO(3), PbSO(4) and/or PbCl(2). Additionally, the filter sample is also divided into water-soluble, 0.1 M HCl-extractable, and residual fractions of Pb compounds by a simple acid extraction procedure. We discuss the possibility of Pb speciation in the particulate samples with combination of highly sensitive XANES spectroscopy and simple acid extraction.


Asunto(s)
Monitoreo del Ambiente/métodos , Plomo/química , Material Particulado/química , Espectrometría por Rayos X/métodos , Ciudades , Ácido Clorhídrico/química , Plomo/análisis , Material Particulado/análisis , Agua/química
5.
J Environ Radioact ; 86(2): 212-26, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16242819

RESUMEN

In order to elucidate the cause for the leaching of iodine in a flooded paddy field, we investigated the transformation of an iodine species affected by the water management of the paddy field. The increased concentration of iodide (I(-)) in soil solution of a flooded paddy field suggested that I(-) was leached from the soil under anaerobic conditions. The post-edge feature of X-ray absorption near-edge structure (XANES) for iodate (IO(3)(-)) spiked to soil totally disappeared after anaerobic incubation of the soils, and I(-) was dissolved in the solution. On the other hand, I(-) in contact with the soil was not likely to be oxidized to IO(3)(-) under aerobic incubation. Iodine was leached out in soil solution as I(-) under anaerobic conditions, whereas part of the iodine species was retained by soil as I(2) or organoiodine both under anaerobic and aerobic conditions.


Asunto(s)
Yodo/química , Suelo/análisis , Análisis Espectral/métodos , Oxidación-Reducción , Rayos X
6.
Intern Med ; 37(9): 762-5, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9804084

RESUMEN

A 47-year-old man presented with acute renal failure following oxalate ingestion. Nausea and hematoemesis appeared four hours after attempted suicide and acute oliguric renal failure ensued the following day. The patient underwent four sessions of hemodialysis and then reverted to normal state. Histopathologic examination of renal biopsy specimen revealed the degeneration of the renal tubular epithelial cells associated with intracellular calcium oxalate crystal deposition. Most of the renal tubules were patent despite the intraluminar crystal deposition. These findings suggest that dysfunction of the renal tubular epithelial cell plays a more important role than tubular obstruction in developing acute renal failure.


Asunto(s)
Oxalato de Calcio/envenenamiento , Necrosis Tubular Aguda/inducido químicamente , Oxalato de Calcio/análisis , Cristalización , Células Epiteliales/química , Células Epiteliales/patología , Humanos , Necrosis Tubular Aguda/sangre , Necrosis Tubular Aguda/patología , Túbulos Renales/química , Túbulos Renales/patología , Masculino , Persona de Mediana Edad , Diálisis Renal , Intento de Suicidio
7.
J Anim Sci ; 65(4): 896-900, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3667462

RESUMEN

Ewes of eight crossbred groups, born in 1973 and 1974, were maintained under two pasture management systems for five and four production years, respectively. After that experiment terminated, those crossbred ewes produced Polypay-sired lambs in 1979 and were then sold. Ewe lambs from those three-bred crosses were backcrossed to Polypay rams to produce lambs from 1980 to 1983. Five ancestor-descendant data sets (three involving dams and daughters and two involving granddams and granddaughters) were examined to study relationships between production efficiency of ancestor ewes and similar traits measured on their descendants. Ancestor cumulative prolificacy was positively but not significantly associated with cumulative prolificacy in the descendants. Regressions of descendant net revenue on ancestor net revenue were predominantly negative but generally were not significant. There was a tendency for prolific ancestors to produce costly but less profitable descendants. These results may be due to economic conditions (high feed costs and low lamb values) that persisted during the course of the experiment.


Asunto(s)
Cruzamientos Genéticos , Preñez/fisiología , Ovinos/genética , Crianza de Animales Domésticos/economía , Animales , Femenino , Embarazo
8.
J Anim Sci ; 66(3): 640-7, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3378921

RESUMEN

Thirty years and 23 yr of life history data from a Hereford herd in Arizona and an Angus herd in Wyoming, respectively, were analyzed. Longevity averaged 4.21 +/- .06 for years from first calving to disposal (FST), 7.40 +/- .06 for years from birth to disposal (AGE) and 3.46 +/- .06 for lifetime number of calves weaned (NUM) in Herefords and 4.49 +/- .13 (FST), 6.68 +/- .12 (AGE) and 3.66 +/- .11 (NUM) in Angus. In the Hereford herd, heritability estimates for traits measuring longevity, estimated from daughter-dam regression and paternal half-sib analyses, ranged from .16 to .26. In the Angus herd, heritability estimates from daughter-dam regression ranged from .03 to .05. In the Hereford herd, genetic correlations of birth weight and weaning weight with longevity, from daughter-dam regression, were negative and generally of low magnitude, whereas genetic correlations between weaning condition score and longevity were positive and moderate. Analogous estimates from paternal half-sib analyses all were positive and moderate to high. Phenotypic correlations between early life traits and longevity traits in Herefords all were near zero. In the Angus herd, curves for age-specific survivorship and age-specific survival rate varied markedly among sires. This study suggested the existence of moderate genetic variation for longevity traits in beef cattle. None of the traits expressed early in life that were examined would, however, be reliable predictors of genetic or phenotypic merit for longevity.


Asunto(s)
Bovinos/genética , Longevidad , Animales , Femenino , Regulación de la Población , Especificidad de la Especie
9.
Health Phys ; 49(6): 1205-15, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4077524

RESUMEN

By the gated counting method that had been developed by the authors the spatial dose distributions at the boundary and inside of a 45-MeV electron linear accelerator (linac) facility were obtained using a NaI(Tl) scintillation probe and a counting system. Both distributions of pulse height and radiation propagation time were also measured. At the facility boundary, dose rates measured ranged from 0.16 microR hr-1 to 0.86 microR hr-1, which were less than one-tenth the natural background. At measurement in the linac control room, two different leakage sources, one originating at and around the accelerator and the other at a microwave power system, were discriminated by measuring pulse height and time distributions simultaneously.


Asunto(s)
Aceleradores de Partículas , Dosis de Radiación , Conteo por Cintilación/métodos , Exposición a Riesgos Ambientales
10.
Health Phys ; 50(6): 797-804, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3710787

RESUMEN

A fixed-point radiation monitoring system based on the gated counting method, which was previously reported by us, was constructed for a 45-MeV electron LINAC facility. It was tested under different beam intensities of the accelerator both at the current and repetition rates. It showed excellent dynamic response (from 2.5 X 10(-11) to 1.0 X 10(-8) Sv h-1) to the intensity variation of the radiation source. It was demonstrated that the system was very useful in monitoring an extremely low-level radiation from a pulsed source.


Asunto(s)
Electrones , Aceleradores de Partículas , Monitoreo de Radiación/métodos
11.
Appl Anim Behav Sci ; 73(1): 45-58, 2001 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-11356290

RESUMEN

Seven experiments were conducted on four miniature pigs to determine: (1) whether the pigs can discriminate between people wearing the same coloured clothing; (2) what cues they rely on if they could discriminate. For 2 weeks before the experiments began, the pigs were conditioned in a Y-maze to receive raisins from the rewarder wearing dark blue coveralls. They were then given the opportunity to choose the rewarder or non-rewarder in these experiments. Each session consisted of 20 trials. Successful discrimination was that the pig chose the rewarder at least 15 times in 20 trials (P<0.05: by chi(2)-test). In Experiment 1, both rewarder and non-rewarder wore dark blue coveralls. By 20 sessions, all pigs successfully identified the rewarder. In Experiment 2: (1) both wore coveralls of the same new colours or (2) one of them wore coveralls of new colours. They significantly preferred the rewarder even though the rewarder and/or non-rewarder wore coveralls of new colours. In Experiment 3, both wore dark blue coveralls but olfactory cues were obscured and auditory cues were not given. The pigs were able to identify the rewarder successfully irrespective of changing auditory and olfactory cues. In Experiment 4, both wore dark blue coveralls but covered part of their face and body in different ways. The correct response rate decreased when a part of the face and the whole body of the rewarder and non-rewarder were covered. In Experiment 5, both wore dark blue coveralls and changed their apparent body size by shifting sitting position. The correct response rate increased as the difference in body size between the experimenters increased. In Experiment 6, the distance between the experimenters and the pig was increased by 30cm increments. The correct response rate of each pig decreased as the experimenters receded from the pig, but performance varied among the pigs. In Experiment 7, the light intensity of the experimental room was reduced from 550 to 80lx and then to 20lx. The correct response rate of each pig decreased with the reduction in light intensity, but all the pigs discriminated the rewarder from the non-rewarder significantly even at 20lx.In conclusion, the pigs were able to discriminate between people wearing coveralls of the same colour after sufficient reinforcement. These results indicate that pigs are capable of using visual cues to discriminate between people.

12.
Rev Sci Instrum ; 83(8): 083112, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22938279

RESUMEN

We have developed a quick-scanning x-ray absorption fine structure (QXAFS) system and installed it at the recently constructed synchrotron radiation beamline BL33XU at the SPring-8. Rapid acquisition of high-quality QXAFS data was realized by combining a servo-motor-driven Si channel-cut monochromator with a tapered undulator. Two tandemly aligned monochromators with channel-cut Si(111) and Si(220) crystals covered energy ranges of 4.0-28.2 keV and 6.6-46.0 keV, respectively. The system allows the users to adjust instantly the energy ranges of scans, the starting angles of oscillations, and the frequencies. The channel-cut crystals are cooled with liquid nitrogen to enable them to withstand the high heat load from the undulator radiation. Deformation of the reflecting planes is reduced by clamping each crystal with two cooling blocks. Performance tests at the Cu K-edge demonstrated sufficiently high data quality for x-ray absorption near-edge structure and extended x-ray absorption fine-structure analyses with temporal resolutions of up to 10 and 25 ms, respectively.

13.
J Colloid Interface Sci ; 388(1): 219-24, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-23014451

RESUMEN

The total reflection X-ray absorption fine structure (TR-XAFS) technique was applied to adsorbed films at the surface of aqueous solutions of surfactant mixtures composed of dodecyltrimethylammonium bromide (DTAB) and dodecyltrimethylammonium tetrafluoroborate (DTABF(4)). The obtained XAFS spectra were expressed as linear combinations of two specific spectra corresponding to fully hydrated bromide ions (free-Br) and partially dehydrated bromide ions adsorbed to the hydrophilic groups of surfactant ions (bound-Br) at the surface. The ratio of free- and bound-Br ions was determined as a function of surface tension and surface composition of the surfactants. Taking also the results in our previous studies on the DTAB - dodecyltrimethylammonium chloride (DTAC) and 1-hexyl-3-methylimidazolium bromide (HMIMBr) - 1-hexyl-3-methylimidazolium tetrafluoroborate (HMIMBF(4)) mixed systems into consideration, the relation between counterion distribution and miscibility of counterions at the solution surface was deduced for the surfactant mixtures having common surfactant ions but different counterions.

14.
J Synchrotron Radiat ; 8(Pt 2): 674-6, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11512892

RESUMEN

Iodine K-edge XAFS of triiodide ions in various solvents were measured at SPring-8 BL01B1 and analyzed. Though the anion takes a linear and symmetric form, the second peak expected from enhanced multiple scatterings can be hardly observed because of its large vibrations. The bond distances and the Debye-Waller factors for the I-I couple vary when protic solvents were used and they were similar when aprotic solvents were used. It was indicated that the larger the Mayers' acceptor number of the solvent is, the larger the Debye-Waller factor is. It was also found that among the aprotic solvents, the larger the Gutmann's donor number is, the smaller the Debye-Waller factor is.

15.
J Dairy Sci ; 67(3): 585-91, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6538887

RESUMEN

Twenty-eight cows were assigned randomly to a daily photoperiod of 18 h light and 6 h darkness or to continuous light and were observed 1 day each month from December 1981 to February 1982. Lighting regimen did not affect eating behavior or milk production. Overall means of total eating time, number of eating bouts, and average time eating per bout on the 3 observation days were 270 to 280 min, 10 to 12 times, and 24 to 27 min. Eating behavior and milk production were not significantly correlated. Eating patterns were similar in both groups and across observation days. Peaks of eating activity occurred before sunset, bracketing the evening milking and after the offering of fresh feed in the morning. Approximately 80% of total eating activity occurred between 0900 and 2100 h in both groups. Cows had a clear preference for entry into the right or left side of the milking parlor, and entry order was repeatable. Milking order and milk production were not correlated. In one group, location of free stalls did not influence utilization; but in the other group, centrally located stalls were utilized more than stalls at either end of the alley. About 40% of cows had individual free stall preferences.


Asunto(s)
Conducta Animal , Bovinos/fisiología , Conducta Alimentaria , Lactancia , Luz , Animales , Femenino , Leche/metabolismo , Embarazo
16.
J Hum Ergol (Tokyo) ; 20(2): 109-21, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1842958

RESUMEN

In the Japanese newspaper industry, since the late 1970s, computerization has been started in large scale. The system, called Computerized Typesetting System (CTS), has been introduced. With this system, all information in the newspaper is input into a computer, called up on a cathode ray display (CRT) to edit, and then output to film or printing plates by CTS. Thus, the work of newspaper production has undergone a major transformation from industrial work to clerical work. It was reported that newspaper production staff working with VDTs complained more than staff working with the older key system about visual and physical problems which affected their job and their daily life. The complaint rates were highest for editors, who used VDT constantly throughout the day. This study was performed to clarify the health impact of VDT use and to prevent health disorders caused by the introduction of CTS. It is concluded that 5 m corrected vision and sphere refraction of CTS workers who used CTS over 2 or 4 hr daily, significantly became worse in a year after the introduction. Therefore, it is indicated that the control of CTS work time is important to prevent the visual disorder.


Asunto(s)
Terminales de Computador , Salud Laboral , Edición , Trastornos de la Visión/etiología , Adulto , Humanos , Masculino , Trastornos de la Visión/prevención & control
17.
Respirology ; 4(1): 93-5, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10339737

RESUMEN

Toxic epidermal necrolysis (TEN) is an acute life-threatening condition, characterized by erosion of the mucous membranes, extensive detachment of the epidermis, and severe constitutional symptoms. Pulmonary complications of TEN are reported as rare, but are one of the most common causes of death. Our report focuses on an unusual case of toxic epidermal necrolysis which showed multiple bronchial obliteration during the chronic phase of the disease. Biopsied tissue of the obliterated bronchi demonstrated non-specific granulation. To improve the obliterated ventilatory function, we tried to reopen the bronchial obliteration using a balloon catheter under the guidance of fibreoptic bronchoscopy, however rapid restenosis of the bronchi ensued.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Enfermedades Bronquiales/etiología , Síndrome de Stevens-Johnson/complicaciones , Adulto , Obstrucción de las Vías Aéreas/patología , Obstrucción de las Vías Aéreas/terapia , Enfermedades Bronquiales/patología , Enfermedades Bronquiales/terapia , Broncoscopía/métodos , Cateterismo , Femenino , Tecnología de Fibra Óptica , Humanos
18.
Acta Crystallogr D Biol Crystallogr ; 55(Pt 6): 1215-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10329771

RESUMEN

FixL is a transmitter protein in a two-component system which acts as an oxygen sensor when the symbiotic Rhizobia resides in root nodules of host plants. The oxygen-sensor domain of Rhizobium meliloti FixL (RmFixLH) was purified by His-tag affinity and isoelectronic focusing chromatographies, without the use of gel-filtration chromatography. Dynamic light-scattering measurements of RmFixLH thus obtained revealed it to be monodispersive and present as a homodimer in solution. A single crystal of RmFixLH in the met (Fe3+) form was grown in 100 mM acetic acid/NaOH buffer at pH 4.6 in the presence of 200 mM ammonium acetate, using 40%(w/v) PEG 4000 as a precipitant. A crystal of the ferrous CO form of RmFixLH was also prepared by reduction of the met crystal with Na2S2O4 in an atmosphere of CO. The crystals (0.2 x 0.05 x 0.01 mm) belong to the monoclinic system (C2) with unit-cell parameters a = 60.94, b = 37.44, c = 54.14 A, beta = 115.29 degrees and diffract X-rays to 1.7 A resolution at station BL44B2 of SPring-8, Japan. Bijvoet difference Patterson maps show a clear peak corresponding to the haem iron in RmFixLH.


Asunto(s)
Proteínas Bacterianas/química , Hemoproteínas/química , Sinorhizobium meliloti/química , Cristalografía por Rayos X , Histidina Quinasa , Luz , Oxígeno/análisis , Conformación Proteica , Dispersión de Radiación , Espectrometría de Fluorescencia
19.
Am J Gastroenterol ; 94(1): 276-8, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9934775

RESUMEN

We report a 61-yr-old woman with acute circulatory failure from spontaneous splenic rupture with decompensated liver cirrhosis complicating large hepatocellular carcinoma exposed on the right liver surface. On admission, the patient was tentatively diagnosed as having rupture of the hepatocellular carcinoma, and she died 15 hours after admission despite blood transfusion. Autopsy revealed that the origin of the intraperitoneal hemorrhage was a ruptured spleen. According to a MEDLINE search of the English-language literature published between 1966 and March 1998, this is the first reported case of spontaneous splenic rupture in a patient with hepatocellular carcinoma without splenic metastasis.


Asunto(s)
Carcinoma Hepatocelular/complicaciones , Neoplasias Hepáticas/complicaciones , Rotura del Bazo/complicaciones , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Rotura Espontánea , Rotura del Bazo/diagnóstico , Rotura del Bazo/patología
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