Heat generation density of electric elements increases close to the limit of forced air-cooling. New cooling technology is required and a self-vibration heat pipe is proposed for the electric ...elements cooling. The self-vibration heat pipe, which has a meandering capillary channel, can operate for vertical and horizontal heat removal without gravity effects. However, the behaviors of the working fluid in the pipe have not been well studied. The purpose of this study is to clarify the working fluid phenomena in the heat pipe. The working fluid in the pipe was visualized by neutron radiography system at JRR-3 in Japan Atomic Energy Agency. The liquid columns in the meandering channel of the heat pipe were recorded by a high-speed camera. The obtained images were segmented and the meandering capillary channel was uncoiled by image processing methods to show the temporal vibration of the liquid columns in the stretched channel. Periods of the column oscillation were about 0.5–1.5
s. The oscillation of the columns was analyzed by a mass-spring model. The periods of the oscillation were obtained and compared with the experiment results. It was shown that the analytical values agreed fairly with the experimental ones.
Procalcitonin as an indicator of urosepsis Sugimoto, Koichi; Adomi, Shogo; Koike, Hiroyuki ...
Research and reports in urology,
01/2013, Letnik:
5, Številka:
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Journal Article
Recenzirano
Odprti dostop
Procalcitonin has been advocated as a marker of bacterial infection, so this study was carried out to determine the usefulness of serum procalcitonin in the early diagnosis of urosepsis.
The subjects ...were 37 febrile patients with urinary tract infection in whom we examined the serum procalcitonin concentration at the start of treatment.
Thirty patients had acute pyelonephritis (16 simple, 14 complex), one had emphysematous pyelonephritis, five had acute prostatitis, and one had acute epididymitis. The procalcitonin level was <0.5 ng/mL in 18 patients, ≥0.5 ng/mL in one patient, ≥2 ng/mL in seven patients, and ≥10 ng/mL in 11 patients. Five of the 11 patients with procalcitonin levels ≥ 10 ng/mL had disseminated intravascular coagulation. All patients with urinary tract obstruction and disseminated intravascular coagulation had procalcitonin levels ≥ 10 ng/mL.
Although this retrospective study comprised a small number of patients, we found that procalcitonin was a useful marker for urinary tract infection.
Recently, ultrasonic tissue characterization of the composition of plaques has been performed in a quantitative fashion on the basis of integrated backscatter (IBS) analysis, but most of those ...studies have used high-frequency ultrasound to obtain microscopic images.
We performed B-mode measurement and IBS signal analysis with acoustic densitometry with a 7.5-MHz linear-array transducer in freshly excised human aortas (n=58) (normal, atheromatous, and fibrous tissue) obtained at autopsy. Atheromatous and fibrous tissue had a similar intima-media thickness (IMT), but the IBS value in atheromatous specimens was lower than that in fibrous specimens. We further applied this method to human carotid ultrasonography. The subjects were young (80 regions), middle aged with 1 or no coronary risk factors (low risk) (120 regions), middle aged with >/=2 coronary risk factors (high risk) (240 regions), or elderly (80 regions) or were patients with myocardial infarction (MI) with multivessel disease (90 regions). The IMT was similar in middle-aged, elderly, and MI subjects. In contrast, the IBS value was significantly higher in elderly subjects and lower in high-risk middle-aged and MI subjects compared with that in low-risk middle-aged subjects. The percent of regions diagnosed as atheromatous (IBS less than mean minus 2-SD value of IBS in young subjects) was 11% in low-risk middle-aged subjects, 29% in high-risk middle-aged subjects, and 63% in the MI group.
In conjunction with conventional B-mode imaging, IBS analysis with carotid ultrasonography appeared to provide prognostic information to identify a high-risk group with systemic atherosclerosis, which could lead to coronary heart disease in individuals with early-stage disease.
We examined the effect of high potassium (K) diet on oxidative stress to endothelium in hypertensive rats. Five-week-old stroke-prone spontaneously hypertensive rats (SHRsp) were fed a 5% high NaCl ...diet containing either 0.5% normal K (n = 28) or 2.1% high K (n = 19) for 6 weeks, and lipid peroxides in the aortic intima and plasma were measured. Lipid peroxides were extracted into an organic solvent to avoid the interference of carbohydrates or glycoproteins, and malondialdehyde (MDA) produced from lipid peroxides by acid-heating was measured by its reaction to thiobarbituric acid. The antioxidant butylated hydroxytoluene prevented spurious lipid peroxide formation during the whole procedure, and optimum Fe3+ allowed a maximum MDA production from lipid peroxides. The high K SHRsp showed lower lipid peroxide levels than the normal K SHRsp both in the intima (5.6 +/- 0.3 vs. 7.2 +/- 0.4 nmol MDA/mg fatty acids, p < 0.003) and plasma (0.91 +/- 0.08 vs. 1.46 +/- 0.10 nmol MDA/ml, p < 0.001). Mean arterial pressure was slightly lower by 13 mmHg in the high K SHRsp, but these differences were still obvious even when we compared groups of rats with precisely matching blood pressures. These results indicate that high K diets reduce oxidative stress on the endothelium of high NaCl-fed SHRsp independently of blood pressure changes. This effect may be involved in the mechanism by which high K diets protect endothelium and reduce stroke incidence in hypertensive animals. Thus, we improved the method of lipid peroxide measurement and propose the protective effects of high K diet against oxidative stress to endothelium in hypertension animals.
The mechanical properties of plant organs depend upon anatomical structure, cell-cell adhesion, cell turgidity, and the mechanical properties of their cell walls. By testing the mechanical responses ...of Arabidopsis mutants, it is possible to deduce the contribution that polymers of the cell wall make to organ strength. We developed a method to measure the tensile parameters of the expanded regions of turgid or plasmolyzed dark-grown Arabidopsis hypocotyls and applied it to the fucose biosynthesis mutant mur1, the xyloglucan glycosyltransferase mutants mur2 and mur3, and the katanin mutant bot1. Hypocotyls from plants grown in the presence of increasing concentrations of dichlorobenzonitrile, an inhibitor of cellulose synthesis, were considerably weakened, indicating the validity of our approach. In order of decreasing strength, the hypocotyls of mur2 > bot1 and mur1 > mur3 were each found to have reduced strength and a proportionate reduction in modulus compared with wild type. The tensile properties of the hypocotyls and of the inflorescence stems of mur1 were rescued by growth in the presence of high concentrations of borate, which is known to cross-link the pectic component rhamnogalacturonan II. From comparison of the mechanical responses of mur2 and mur3, we deduce that galactose-containing side chains of xyloglucan make a major contribution to overall wall strength, whereas xyloglucan fucosylation plays a comparatively minor role. We conclude that borate-complexed rhamnogalacturonan II and galactosylated xyloglucan contribute to the tensile strength of cell walls.
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