Fabrication and Characterization of Metal-Loaded Mixed Metal Oxides Gas Sensors for the Detection of Hazardous Gases

This study concerns gas sensors that may protect individuals by detecting hazardous gases that may be generated in hot spaces (≥50°C) with residues of organic waste. We investigated the responses and selectivities of the sensors to different kinds of hazardous gases such as acetaldehyde, toluene and hydrogen sulfide. We also investigated operating temperatures and catalysts for the sensors. The thick film semiconductor sensors that detected some hazardous gases were prepared using nano-sized sensing material powders (SnO2, WO3, ZnO) that were prepared through sol-gel and precipitation methods. The nano-sized sensing materials were blended with various amounts of metal oxides (SnO2, ZnO, WO3) and coated with transition metals (Pt, Pd, Ru, Au, Ag, Cu and In). The metal oxide thick films were fabricated on an Al2O3 plate with a Ni-Cr heater and a Pt electrode through a screen-printing method. Morphologies, compositions, phases, surface areas and particle sizes of sensor compounds were examined by SEM, EDS, XRD and BET analysis. The investigated response to the various hazardous vapors was expressed as the value of Ra/Rg, where Ra and Rg are the resistance of the sensor material in the air and in hazardous gas, respectively

Contact holes in vertical electrode structures analyzed by voltage contrast-SEM and conducting AFM

Soaring demands of multi-stacked memory devices request urgent development of backside contact electrode technologies, such as high aspect ratio etching, metallization, and inspection methods. Especially the complex metal contact process should be monitored for each manufacturing step to filter the defective samples and to maintain the high yield of production. Among the inspection methods for detecting the electrical connections, there is voltage contrast (VC)-SEM and conducting AFM (C-AFM). In this report, we investigated the two inspection methods for testing designed samples with different contact hole states. The VC-SEM data shows the contrast variation at the contact holes, from which one may discern the contact status with an optimum voltage. The C-AFM results clearly demonstrate a finite electrical current in the connected contact, while a negligible current in the disconnected one. Finally, we discuss insights of using the two methods for analyzing the contact hole technologies with high aspect ratios.Comment: 17 pages, 4 figure

Efficacy of Anticholinergics for Chronic Prostatitis/Chronic Pelvic Pain Syndrome in Young and Middle-Aged Patients: A Single-Blinded, Prospective, Multi-Center Study

Purpose Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) exhibits variable lower urinary tract symptoms (LUTS). The aim of this study was to evaluate the incidence of LUTS and the efficacy of an anticholinergic agent in young and middle-aged CP/CPPS patients. Methods Ninety-six men with CP/CPPS were randomly assigned in a single-blind fashion and received either ciprofloxacin (group 1, 49 patients) or ciprofloxacin and solifenacin (5 mg/day; group 2, 47 patients) for 8 weeks. The National Institutes of Health chronic prostatitis symptom index (NIH-CPSI), the International Prostate Symptom Score (IPSS), and the International Index of Erectile Function-5 (IIEF-5) were used to grade the patients' symptoms and the quality of life impact at the start of the study, and at 4 and 8 weeks from the initiation of the study. Results There was no significant difference between groups 1 and 2 with respect to age, duration of disease, or sub-domains of the IPSS, NIH-CPSI, or IIEF-5 at baseline. Of these patients, 67.4% had LUTS. Statistically significant differences were determined via the NIH-CPSI for total score and the pain and urinary domain scores. Statistically significant differences were determined via the IPSS for total score and the storage domain score. The total score of the IIEF-5 increased, but the change was not significant. There was no statistically significant difference in residual urine. Conclusions Many CP/CPPS patients had LUTS. Solifenacin in CP/CPPS demonstrated improvements in the NIH-CPSI and the IPSS total score and storage score. Storage factors significantly improved via the NIH-CPSI and IPSS assessments in the solifenacin treatment group

Analysis of Initial Baseline Clinical Parameters and Treatment Strategy Associated with Medication Failure in the Treatment of Benign Prostatic Hyperplasia in Korea

Purpose To analyze the baseline clinical factors and medication treatment strategy used in cases with medication treatment failure of benign prostatic hyperplasia (BPH). Methods From January 2006 to December 2009, 677 BPH patients with at least 3 months of treatment with medication were enrolled. We analyzed clinical factors by medication failure (n=161) versus maintenance (n=516), by prostate size (less than 30 g, n=231; 30 to 50 g, n=244; greater than 50 g, n=202), and by prostate-specific antigen (PSA) levels (less than 1.4 ng/mL, n=324; more than 1.4 ng/mL, n=353). Results Age, combination medication rate, PSA, and prostate volume were statistically different between the medication treatment failure and maintenance groups. By prostate size, the PSA and medication failure rates were relatively higher and the medication period was shorter in patients with a prostate size of more than 30 g. The combination medication rate was higher in patients with a prostate size of more than 50 g. The medication failure rate and prostate volume were higher in patients with a PSA level of more than 1.4 ng/mL. However, the combination treatment rate was not significantly different in patients with a PSA level lower than 1.4 ng/mL. Suggestive cutoffs for combination medication are a prostate volume of 34 g and PSA level of 1.9 ng/mL. Conclusions The clinical factors associated with medication failure were age, treatment type, and prostate volume. Combination therapy should be considered more in Korea in patients with a PSA level higher than 1.4 ng/mL and a prostate volume of between 30 and 50 g to prevent medication failure

The effect of fermented buckwheat on producing L-carnitine enriched oyster mushroom

L-carnitine is biological compound which serves intake of long chain fatty acids into mitochondria. In market, L-carnitine is considered as nutritious supplements for weight-loss. L-carnitine is synthesized in human organ, but most of L-carnitine which human intakes are originated from meat based foods. Oyster mushroom (Pleurotus ostreatus), the second popular edible mushroom in the world, is the main source of L-carnitine after meat and pork. Recently, there were many efforts to study designer foods of which functional ingredients were increased. However most of studies were focused on dairy products. In this study, the fermented buckwheat by Rhizopus oligosporus that contained high L-carnitine contents were used to cultivate oyster mushroom. L-carnitine contents in oyster mushroom were quantified by LC-ESI-MS. Mushroom grown on buckwheat medium had 3.17 to 23.88% higher L-carnitine concentration than normal medium. The mushroom size was increased when 20% (w/w) of buckwheat was added to basal medium. The lightness of mushroom pileus (L*) significantly increased among all the treatments. These results demonstrate that buckwheat and fermented buckwheat is novel substrates to produce L-carnitine enriched functional mushroom.OAIID:RECH_ACHV_DSTSH_NO:A201702463RECH_ACHV_FG:RR00200003ADJUST_YN:EMP_ID:A079459CITE_RATE:FILENAME:태경.pdfDEPT_NM:국제농업기술학과EMAIL:[email protected]_YN:FILEURL:https://srnd.snu.ac.kr/eXrepEIR/fws/file/34dfad8a-5bc9-41cd-8160-c7846937fa22/linkCONFIRM:

Clinical significance of hypoalbuminemia in outcome of patients with scrub typhus

<p>Abstract</p> <p>Background</p> <p>This study was designed to investigate the clinical significance of hypoalbuminemia as a marker of severity and mortality in patients with Scrub typhus.</p> <p>Methods</p> <p>The patients with scrub typhus were divided into two groups based on the serum albumin levels; Group I (serum albumin <3.0 g/dL) and Group II (serum albumin ≥3.0 g/dL). The outcome of patients with hypoalbuminemia was compared with that of normoalbuminemia.</p> <p>Results</p> <p>Of the total 246 patients who underwent the study, 84 patients (34.1%) were categorized as Group I and 162 patients were (65.9%) as Group II. Group I showed significantly higher incidence of confusion (24.6% vs. 5.3%, <it>p </it>< 0.001), pulmonary edema (15.8% vs. 3.2%, <it>p </it>= 0.002), pleural effusion (22.8% vs. 11.1%, <it>p </it>= 0.03), arrhythmia (12.3% vs. 2.6%, <it>p </it>= 0.008) and non-oliguric acute renal failure (40.4% vs. 11.1%, <it>p </it>< 0.001) compared to group II. Hypoalbuminemic group had a higher APACHE II score (11.37 ± 5.0 vs. 6.94 ± 4.2, <it>p </it>< 0.001), longer hospital stay (19.9 ± 42.1 days vs 7.5 ± 13.8 days, <it>p </it>= 0.012), and higher hospital cost compared to Group II.</p> <p>Conclusions</p> <p>This study showed hypoalbuminemia in scrub typhus was closely related to the frequency of various complication, longer hospital stay, consequently the higher medical cost, necessitating more efficient management of patients, including medical resources.</p

Sleep Status and the Risk Factor of Drowsy-Related Accidents in Commercial Motor Vehicle Drivers

Background and Objective The purpose of this study was to describe prevalence of sleep problems including obstructive sleep apnea (OSA), insomnia, and sleep insufficiency in commercial motor vehicle (CMV) drivers, and to quantify risk of drowsy-related accidents in CMV drivers. Methods CMV drivers were invited to participate in this study. Participants were asked to complete a questionnaire about sleep habits, sleep disorders, work environments, and experience of drowsy-related accidents. A home sleep test (Watch-PAT 200) was also undertaken to detect OSA. Results Among 110 participants, 89 with eligible data of questionnaires and home sleep tests were included in the analysis. 91.0% of participants had OSA with peripheral arterial tonometry respiratory distress index (pRDI) ≥ 5/h and 23.6% had moderate to severe OSA with pRDI ≥ 15/h. 55.1% perceived that their sleep is insufficient. 52.3% of participants experienced drowsy driving. Drowsy driving-related motor vehicle crashes (MVCs) and near miss MVCs were reported by 9.6% and 37.9% of participants, respectively. Multiple regression analysis showed that increased risk of drowsy driving was associated with perceived sleep insufficiency [odds ratio (OR) = 3.48, 95% confidence interval (CI) 1.26–9.64]. Increased risk of drowsy driving-related near miss MVC was associated with perceived sleep insufficiency (OR = 3.06, 95% CI 1.11–8.44) and continuous driving for more than 4 hours (OR = 3.10, 95% CI 1.00–9.58). Conclusions OSA and perceived sleep insufficiency are prevalent in CMV drivers. Perceived sleep insufficiency and longer continuous driving hours increased risk of drowsy-related accidents