346 research outputs found

    Pulse-Laser Powered Orbital Launcher

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    Household smoking and dental caries in schoolchildren: the Ryukyus Child Health Study

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    <p>Abstract</p> <p>Background</p> <p>Secondhand smoke exposure (SHSe) is perhaps one of the most important toxic exposures in childhood. However, epidemiological studies on the relation between SHSe and dental caries are limited and have yielded inconsistent results. The present cross-sectional study examined the potential association between SHSe at home and the prevalence of dental caries in children.</p> <p>Methods</p> <p>Subjects were 20,703 schoolchildren aged 6 to 15 years in Okinawa, Japan. Information on SHSe at home and potential confounding factors was obtained through questionnaires. Data on dental caries were obtained from school records. Children were classified as having decayed and/or filled teeth (DFT) if a dentist diagnosed these conditions. Additionally, we analyzed decayed teeth (DT) and filled teeth (FT) separately. Adjustment was made for sex, age, region of residence, toothbrushing frequency, use of fluoride, sugar intake, and paternal and maternal educational level.</p> <p>Results</p> <p>The prevalence of DFT was 82.0%. Compared with never smoking in the household, former and current household smoking were independently associated with an increased prevalence of DFT (adjusted prevalence ratios [95% confidence intervals] for former household smoking and current light and heavy household smoking were 1.03 [1.00-1.05], 1.04 [1.02-1.05], and 1.04 [1.03-1.06], respectively); when analyzed separately there was an increased prevalence of DT (adjusted prevalence ratios [95% confidence intervals] for former household smoking and current light and heavy household smoking were 1.06 [1.02-1.11], 1.10 [1.06-1.13], and 1.10 [1.07-1.14], respectively) but not FT. A statistically significant dose-response relationship between cumulative smoking in the household and the prevalence of DFT and DT (<it>P </it>for trend < 0.0001), but not FT, was observed. In an analysis of 2 subgroups, subjects who had at least 1 deciduous tooth and subjects who had at least 1 permanent tooth, household smoking exposure was associated with an increased prevalence of DFT and DT not only in those with deciduous but also those with permanent dentition.</p> <p>Conclusion</p> <p>Our findings suggested that household smoking might be associated with an increased prevalence of dental caries in children.</p

    Effect of ciliary neurotrophic factor (CNTF) on motoneuron survival

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    We have demonstrated that the extensive degeneration of motoneurons in the rat facial nucleus after transection of the facial nerve in newborn rats can be prevented by local ciliary neurotrophic factor (CNTF) administration. CNTF differs distinctly from known neurotrophic molecules such as NGF, BDNF and NT-3 in both its molecular characteristics (CNTF is a cytosolic rather than a secretory molecule) and its broad spectrum of biological activities. CNTF is expressed selectively by Schwann cells and astrocytes of the peripheral and central nervous system, respectively, but not by target tissues of the great variety of CNTF -responsive neurons. CNTF mRNA is not detectable by Northern blot or PCR analysis during embryonic development and immediately after birth. However, during the second post-natal week, a more than 30-fold increase in CNTF mRNA and pro tein occurs in the sciatic nerve. Since the period of low CNTF levels in peripheral nerves coincides with that of high vulnerability of motoneurons (i.e. axonallesion results in degeneration of motoneuron cell bodies), insufficient availability of CNTF may be the reason for the rate of lesioninduced cell death of early post-natal motoneurons. Highly enriched embryonic chick motoneurons in culture are supported at survival rates higher than 60% by CNTF, even in single cell cultures, indicating that CNTF acts directly on motoneurons. In contrast to CNTF, the members of the neurotrophin gene family (NGF, BDNF and NT-3) do not support the survival of motoneurons in culture. However, aFGF and bFGF show distinct survival activities which are additive to those of CNTF, resulting in the survival of virtually all motoneurons cultured in the presence of CNTF and bFGF

    Oscillation Reduction of an Anode-Layer-Type Hall Thruster by Azimuthal Propellant onuniformity

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    Discharge current oscillation in the frequency range of 10-100 kHz causes serious problems in using anode layer type Hall thrusters in space. As a novel approach to stabilize the discharge, azimuthally nonuniform propellant flow was created in an acceleration channel. A plenum chamber and hollow anodes were azimuthally divided into two or four sections and xenon flow rates supplied to them were controlled. As a result, the oscillation amplitude significantly decreased and oscillation-free operation was achieved at all magnetic flux densities

    Influence of Discharge Oscillation on Hall Thruster Performance *

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    Influence of discharge oscillations at frequency range of 10-100kHz was investigated using the 1kW class sheath type Hall thruster. Lifetime, that is, wall erosion was examined by means of spectroscopy. The erosion rate in unstable operation was twice as large as that in stable operation. Plume divergence was also measured. The full angle at half maximum of thruster plume was increased from 14.4 to 18.2 degree when the operation was changed from stable operation to unstable operation. However, the oscillation amplitude had little relation with the erosion rate, the plume divergence and the thruster performance. These results would indicate that the ionization zone configuration would affect lifetime, the plume divergence, thruster performance and oscillation rather than oscillation in itself would affect lifetime, the plume divergence and thruster performance

    Combination of Real-Value Smell and Metaphor Expression Aids Yeast Detection

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    Background: Smell provides important information about the quality of food and drink. Most well-known for their expertise in wine tasting, sommeliers sniff out the aroma of wine and describe them using beautiful metaphors. In contrast, electronic noses, devices that mimic our olfactory recognition system, also detect smells using their sensors but describe them using electronic signals. These devices have been used to judge the freshness of food or detect the presence of pathogenic microorganisms. However, unlike information from gas chromatography, it is difficult to compare odour information collected by these devices because they are made for smelling specific smells and their data are relative intensities. Methodology: Here, we demonstrate the use of an absolute-value description method using known smell metaphors, and early detection of yeast using the method. Conclusions: This technique may help distinguishing microbial-contamination of food products earlier, or improvement o

    アノードレイヤ型ホールスラスタの作動特性

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    Thrust performance and stable operation conditions of an anode layer type Hall thruster was investigated using a 1.5kW class anode layer type Hall thruster. The thrust efficiency reached at 53% with the specific impulse of 2,000s, which are competitive with these of SPT-100 thrusters. Anode shape and axial position of the anode were changed. Stability of the discharge was found sensitive to the anode configuration and applied magnetic flux density

    Iron deposition in autopsied liver on patients receiving long-term TPN

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    Background Vitamins and minerals are routinely administered by total parenteral nutrition (TPN). However, in Japan, adjustments in iron dosage are difficult because blended mineral preparations are often used. It is therefore unclear whether the iron content is appropriate in cases of long-term TPN. The aim of the study was to assess the influence of iron administration by long-term TPN on iron deposition in post-mortem liver samples isolated from older deceased patients. Methods Liver tissues were collected from post-mortem autopsies of 187 patients over a period of 15 years. Samples were stained with Prussian blue and histologically evaluated from Grade 0–V by at least three different observers. Specimens with positive and negative iron staining were compared, and positive samples were grouped according to the level and distribution of the staining. Post-mortem blood obtained from the subclavian vein during autopsy was also analysed. Samples were collected for the measurement of unsaturated serum iron, serum iron, albumin, prealbumin, hepcidin, and IL-6 concentrations. Results Iron accumulation in the liver was significantly higher in male patients (p = 0.005) with a history of surgery (p = 0.044) or central vein administration of iron (p<0.001). Additionally, the duration of TPN in the iron-positive group was significantly longer than in the iron-negative group (p = 0.038). Serum analysis revealed that unsaturated serum iron was significantly higher in the iron-negative group and that ferritin and serum iron were significantly higher in the iron-positive group. No other statistically significant differences were observed between the two groups. Conclusions Chronic intravenous administration of iron was associated with iron deposition in the liver, even when given the minimum recommended dosage. In long-term TPN patients, the iron dose should therefore be carefully considered

    Outcome of emergency one-stage resection and anastomosis procedure for patients with obstructed colorectal cancer

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    Purposes : The purpose of this study was to verify the outcome of the emergency one stage resection and anastomosis procedure for patients with obstructed colorectal cancer. Methods : An emergency one stage resection and anastomosis procedure was performed for 40 patients with obstructive colorectal cancer. The outcome was verified and compared dividing into two groups. 17 patients under the age of 70 in (Group A), 23 patients 70 years and over in (Group B). Results : The operative mortality rate in both groups was 0%. As a result, postoperative complications were not significantly different between the two groups. The overall survival rate after a 5-year period in both groups was 41.8%, regarding all patients and the survival curves for the two groups, was not significantly different. The 5 year survival rate in stage II or III showed no differences between the two groups. Conclusion : The one-stage resection and anastomosis of the large bowel could be applied safely to emergency patients, which in turn allows for excellent shortterm operative results in both groups mentioned. This particular procedure should be positively enforced, even in elderly patients in their 70’s

    Switching to Dupilumab from Other Biologics without a Treatment Interval in Patients with Severe Asthma: A Multi-Center Retrospective Study

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    Background: Dupilumab is a fully humanized monoclonal antibody that blocks interleukin4 and interleukin-13 signals. Several large clinical trials have demonstrated the efficacy of dupilumab in patients with severe asthma. However, few studies have examined a switch to dupilumab from other biologics. Methods: This retrospective, multi-center observational study was conducted by the Okayama Respiratory Disease Study Group. Consecutive patients with severe asthma who were switched to dupilumab from other biologics without a treatment interval between May 2019 and September 2021 were enrolled. Patients with a treatment interval of more than twice the standard dosing interval for the previous biologic prior to dupilumab administration were excluded. Results: The median patient age of the 27 patients enrolled in this study was 57 years (IQR, 45-68 years). Eosinophilic chronic rhinosinusitis (ECRS)/chronic rhinosinusitis with nasal polyp (CRSwNP) was confirmed in 23 patients. Previous biologics consisted of omalizumab (n = 3), mepolizumab (n = 3), and benralizumab (n = 21). Dupilumab significantly improved FEV1 (median improvement: +145 mL) and the asthma control test score (median improvement: +2). The overall response rate in patients receiving dupilumab for asthma as determined using the Global Evaluations of Treatment Effectiveness (GETE) was 77.8%. There were no significant differences in the baseline characteristics of the GETE-improved group vs. the non-GETE-improved group. ECRS/CRSwNP improved in 20 of the 23 patients (87.0%). Overall, 8 of the 27 patients (29.6%) developed transient hypereosinophilia (>1500/ mu L), but all were asymptomatic and able to continue dupilumab therapy. Conclusions: Dupilumab was highly effective for the treatment of severe asthma and ECRS/CRSwNP, even in patients switched from other biologics without a treatment interval
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