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Loss of Metalworking Fluids Collected on PVC Filter Due to Contact with Clean Air and Desiccation (PVC필터에 채취된 절삭유의 손실에 관한 연구)

  • Park, Dong-Uk;Ha, Kwon-Chul
    • Analytical Science and Technology
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    • v.14 no.5
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    • pp.451-457
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    • 2001
  • Because liquids with high molecular weight such as mineral oil have low vapor pressure at room temperature, it is generally thought to be difficult to lose them to evaporation. However, when they are dispersed into air in small droplets during application in machining processes, their surface area becomes considerably higher. To determine the potential for metalworking fluids (MWF) filter losses, MWF mist was generated and collected on polyvinyl chloride (PVC) filters in test chamber. After collected MWF was exposed to clean air during designated period (range 10~240 minutes) and the filters were desiccated, losses were evaluated. As duration of clean air passing through PVC filter increased, loss of MWF gradually increased. MWF lost after 10 minutes ranged form 12.4 % to 21.8 % of the original loading mass, on average 53.3 % of the total loss. These results indicate that significant mass of MWF collected on PVC filters can be lost at the beginning of air sampling. Loss of MWF collected on PVC filter also occurred during desiccation without active airflow. In multiple regression to identify which factors influence the loss of MWF collected on PVC filter, both duration of air passing through PVC filter and MWF age (fresh vs. used) were significant predictor (p=0.0001). Therefore, workers' exposure to MWF measured method 0500, may underestimate true concentration. Further study is needed to develop a new method to quantify the workers' exposure to airborne MWF mist accurately.

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Increased Vascular Endothelial Growth Factor in the Ventricular Cerebrospinal Fluid as a Predictive Marker for Subsequent Ventriculoperitoneal Shunt Infection : A Comparison Study among Hydrocephalic Patients

  • Lee, Jeong-Hyun;Back, Dong-Bin;Park, Dong-Hyuk;Cha, Yoo-Hyun;Kang, Shin-Hyuk;Suh, Jung-Keun
    • Journal of Korean Neurosurgical Society
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    • v.51 no.6
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    • pp.328-333
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    • 2012
  • Objective : The aim of this study is to determine the association between the cerebrospinal fluid (CSF) biomarkers and inflammation, and the predictive value of these CSF biomarkers for subsequent shunt associated infection. Methods : We obtained CSF samples from the patients with hydrocephalus during ventriculoperitoneal (VP) shunt operations. Twenty-two patients were enrolled for this study and divided into 3 groups: subarachnoid hemorrhage (SAH)-induced hydrocephalus, idiopathic normal pressure hydrocephalus (INPH) and hydrocephalus with a subsequent shunt infection. We analyzed the transforming growth factor-${\beta}1$, tumor necrosis factor-${\alpha}$, vascular endothelial growth factor (VEGF) and total tau in the CSF by performing enzyme-linked immunosorbent assay. The subsequent development of shunt infection was confirmed by the clinical presentations, the CSF parameters and CSF culture from the shunt devices. Results : The mean VEGF concentration (${\pm}$standard deviation) in the CSF of the SAH-induced hydrocephalus, INPH and shunt infection groups was $236{\pm}138$, $237{\pm}80$ and $627{\pm}391$ pg/mL, respectively. There was a significant difference among the three groups (p=0.01). Between the SAH-induced hydrocephalus and infection groups and between the INPH and infection groups, there was a significant difference of the VEGF levels (p<0.01). However, the other marker levels did not differ among them. Conclusion : The present study showed that only the CSF VEGF levels are associated with the subsequent development of shunt infection. Our results suggest that increased CSF VEGF could provide a good condition for bacteria that are introduced at the time of surgery to grow in the brain, rather than reflecting a sequel of bacterial infection before VP shunt.

Effect of Sling Lmubar Stabilization Exercise Program on the Balance of Adolescent Idiopathic Scoliosis Patients (슬링 요부안정화 운동프로그램이 청소년기 특발성 척추측만증 환자의 균형에 미치는 영향)

  • Bae, Young-Hyeon;Park, Sun-Hee;Lee, Hye-Lim;Lee, Suk-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.7
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    • pp.3074-3084
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    • 2012
  • The purpose of this study lies in examining how sling lumbar stabilization exercise affects static standing balance of adolescent idiopathic scoliosis patients. The subjects were forty patients who were diagnosed with idiopathic scoliosis. They were randomly assigned either to a experimental group (n=20) that received sling lmubar stabilization exercise program or to a control group (n=20) that received only education. Data were obtained for each patient from total sway path and sway velocity in standing on both feet with eyes closed and standing on both feet with eyes open were measured, using balance performance monitor. All variables were measured at pre- and post-exercise. There were significantly differences between the both groups for all variables at post-exercise (p<.05). The experimental group showed a significantly decreases in all variables at pre- and post-exercise (p<.05). But the control group showed a no significantly differences. These results revealed that sling lumbar stabilization exercise improved static standing balance, by reducing COP(center of pressure) sway path and sway velocity of idiopathic scoliosis patients, and it is expected that sling lumbar stabilization exercise will be used as balance enhancement exercise intervention for the treatment of adolescent idiopathic scoliosis patients.

Body Mass Index and Subsequent Risk of Hypertension, Hyperglycemia and Hypercholesterolemia in Health Checkup Examinees (건강검진 수검자들의 비만도와 고혈압, 고혈당 및 고콜레스테롤혈증과의 관련성)

  • Wang, Seong-Bae;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.6
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    • pp.2677-2684
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    • 2011
  • This study was conducted to clarify relationships between BMI and the incidence of hypertension, hyperglycemia and hypercholesterolemia among health checkup examinees. The study sample consists of 3,402 adults aged 30s - 60s years, who underwent health check-up at a university hospital. during the Jan. 2007 to Dec. 2008.As a results, blood pressure level at the base line, ORs(95% CI) of hypertension compared with BMI category of 18.5-22.9(normal group) were 1.7(1.2-3.8) for obesity group I, and 2.9(1.7-6.2) for obesity group II. After adjusting for age and sex, ORs(95% CI) of hypertension compared with BMI category of normal group were 1.3(1.0-1.7) for obesity group I, 1.8(1.3-2.4) for obesity group II. Serum total cholesterol level at the base line, ORs(95% CI) of hypercholesterolemia compared with BMI category of normal group were 1.7(1.5-4.9) for obesity group I, and 2.8(1.8-5.3) for obesity group II. After adjusting for age and sex, ORs(95% CI) of hypercholesterolemia compared with BMI category of normal group were 1.5(1.1-1.9) for obesity group I, and 2.3(1.7-3.1) for obesity group II.

Effects of Aerobic Exercise on Serum Blood Lipids, Leptin, Ghrelin, and HOMA-IR Factors in Postmenopausal Obese Women (유산소 운동이 폐경 후 비만여성의 혈청지질, 렙틴, 그렐린 및 인슐린저항성지수에 미치는 영향)

  • Lee, Jeong-Ah;Kim, Ji-Hyeon;Kim, Jong-Won;Kim, Do-Yoen
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.2
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    • pp.549-558
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    • 2017
  • The aim of this study was to analyze the effects of aerobic exercise on the blood lipids, leptin, ghrelin, and HOMA-IR factors in obese postmenopausal Korean women. Thirty-six healthy postmenopausal women (mean age, $54.47{\pm}2.50$ years) with >32 % body fat were assigned randomly to an aerobic exercise group (n = 18) or to a "no exercise" control group (n = 18). The subjects' body composition, blood lipid, leptin, ghrelin levels, and HOMA-IR were measured before and after a 16-week line-dancing program. The exercise group showed a significant decrease in body weight, percent body fat, body mass index, visceral fat area, leptin, insulin, glucose, HOMA-IR, total cholesterol, triglycerides, apolipoprotein B, low-density lipoprotein cholesterol, and systolic and diastolic blood pressure. In addition, this group exhibited a significant increase in the apolipoprotein A-I, ghrelin, and high-density lipoprotein cholesterol levels. The energy metabolic factors that influenced the visceral fat included ghrelin, leptin, insulin, glucose, and HOMA-IR. The t-value, which determined the statistical significance of the independent variables, was significant for ghrelin, glucose, insulin, and HOMA-IR (p < 0.05). Regular and continuous aerobic exercise (e.g., line dancing) effectively improved the body composition, visceral fat, serum blood lipids, leptin, ghrelin, and HOMA-IR factors in obese postmenopausal Korean women.

Rainfed Areas and Animal Agriculture in Asia: The Wanting Agenda for Transforming Productivity Growth and Rural Poverty

  • Devendra, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.1
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    • pp.122-142
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    • 2012
  • The importance of rainfed areas and animal agriculture on productivity enhancement and food security for economic rural growth in Asia is discussed in the context of opportunities for increasing potential contribution from them. The extent of the rainfed area of about 223 million hectares and the biophysical attributes are described. They have been variously referred to inter alia as fragile, marginal, dry, waste, problem, threatened, range, less favoured, low potential lands, forests and woodlands, including lowlands and uplands. Of these, the terms less favoured areas (LFAs), and low or high potential are quite widely used. The LFAs are characterised by four key features: i) very variable biophysical elements, notably poor soil quality, rainfall, length of growing season and dry periods, ii) extreme poverty and very poor people who continuously face hunger and vulnerability, iii) presence of large populations of ruminant animals (buffaloes, cattle, goats and sheep), and iv) have had minimum development attention and an unfinished wanting agenda. The rainfed humid/sub-humid areas found mainly in South East Asia (99 million ha), and arid/semi-arid tropical systems found in South Asia (116 million ha) are priority agro-ecological zones (AEZs). In India for example, the ecosystem occupies 68% of the total cultivated area and supports 40% of the human and 65% of the livestock populations. The area also produces 4% of food requirements. The biophysical and typical household characteristics, agricultural diversification, patterns of mixed farming and cropping systems are also described. Concerning animals, their role and economic importance, relevance of ownership, nomadic movements, and more importantly their potential value as the entry point for the development of LFAs is discussed. Two examples of demonstrated success concern increasing buffalo production for milk and their expanded use in semi-arid AEZs in India, and the integration of cattle and goats with oil palm in Malaysia. Revitalised development of the LFAs is justified by the demand for agricultural land to meet human needs e.g. housing, recreation and industrialisation; use of arable land to expand crop production to ceiling levels; increasing and very high animal densities; increased urbanisation and pressure on the use of available land; growing environmental concerns of very intensive crop production e.g. acidification and salinisation with rice cultivation; and human health risks due to expanding peri-urban poultry and pig production. The strategies for promoting productivity growth will require concerted R and D on improved use of LFAs, application of systems perspectives for technology delivery, increased investments, a policy framework and improved farmer-researcher-extension linkages. These challenges and their resolution in rainfed areas can forcefully impact on increased productivity, improved livelihoods and human welfare, and environmental sustainability in the future.

Fumonisin B1 Contamination of Cereals and Risk of Esophageal Cancer in a High Risk Area in Northeastern Iran

  • Alizadeh, Ali Mohammad;Roshandel, Gholamreza;Roudbarmohammadi, Shahla;Roudbary, Maryam;Sohanaki, Hamid;Ghiasian, Seyed Amir;Taherkhani, Amir;Semnani, Shahryar;Aghasi, Maryam
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2625-2628
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    • 2012
  • Introduction: Fumonisin B1 (FB1) is a toxic and carcinogenic mycotoxin produced in cereals due to fungal infection. This study was conducted to determine FB1 contamination of rice and corn samples and its relationship with the rate of esophageal cancer (EC) in a high risk area in northeastern Iran. Methods: In total, 66 rice and 66 corn samples were collected from 22 geographical subdivisions of Golestan province of Iran. The levels of FB1 were measured for each subdivision by thin layer and high pressure liquid chromatographies. The mean level of FB1 and the proportions of FB1 contaminated samples were compared between low and high EC-risk areas of the province. Results: The mean of FB1 levels in corn and rice samples were 223.64 and 21.59 ${\mu}g/g$, respectively. FB1 contamination was found in 50% and 40.9% of corn and rice samples, respectively. FB1 level was significantly higher in rice samples obtained from high EC-risk area (43.8 ${\mu}g/g$) than those obtained from low risk area (8.93 ${\mu}g/g$) (p-value=0.01). The proportion of FB1 contaminated rice samples was also significantly greater in high (75%) than low (21.4%) EC-risk areas (p-value=0.02). Conclusion: We found high levels of FB1 contamination in corn and rice samples from Golestan province of Iran, with a significant positive relationship between FB1 contamination in rice and the risk of EC. Therefore, fumonisin contamination in commonly used staple foods, especially rice, may be considered as a potential risk factor for EC in this high risk region.

Dietary flavan-3-ols intake and metabolic syndrome risk in Korean adults

  • Yang, Yoon-Jung;Kim, You-Jin;Yang, Yoon-Kyoung;Kim, Ji-Yeon;Kwon, O-Ran
    • Nutrition Research and Practice
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    • v.6 no.1
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    • pp.68-77
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    • 2012
  • Flavan-3-ols are a subclass of flavonoids found in a variety of foods including teas. The effects of flavan-3-ols on the risk of metabolic syndrome (MetS) have been investigated, generally focusing on tea catechins or individual flavan-3-ol rich foods, but there is little information on dietary flavan-3-ols intake and risk of MetS in population-based studies. In this cross-sectional study, we examined the association between dietary flavan-3-ols intake and the risk of MetS in Korean adults. Subjects comprised 1,827 men and 2,918 women aged 20-69 years whose data was included in the 2008 Korean National Health and Nutrition Examination Survey. This survey was conducted between January 2008 and December 2008. Total flavan-3-ols intakes were calculated from 24-hour dietary recalls using a flavonoids database. Thirty percent of the male subjects and 24% of the female subjects were reported as having MetS. In the female subjects, flavan3-ols intake was inversely associated with the risk of MetS after adjusting for potential confounders (5th vs. 1st quintile, OR=0.64, 95% CI=0.45-0.91, P for trend=0.384). The main food source of flavan-3-ols was green tea followed by apples and grapes. Among MetS components, flavan-3-ols intake was inversely associated with the risk of high blood pressure after adjusting for potential confounders (5th vs. 1st quintile, OR=0.64, 95% CI=0.45-0.90, P for trend=0.005). No significant association between flavan-3-ols intake and risk of MetS was found in the male subjects. After stratified analysis by obesity (BMI ${\geq}$ 25 or BMI < 25), however, flavan3-ols intake was inversely related to the risk of hypertension in non-obese men. These results suggest that dietary flavan-3-ols intake may have beneficial effects on MetS risk by reducing the risk of hypertension. The effects of flavan-3-ols intake dependent on obesity need further investigation.

A Study on the Serum Lipid, Apolipoprotein Levels and Their Correlations in Healthy Adults of Gyeongnam Area (경남지역 중${\cdot}$장년층의 혈청지질, 아포지단백질의 농도 및 상호관련성에 관한 연구)

  • Lee, Hoe-Seon;Park, Mi-Young;Kim, Gyeong-Eup;Cheong, Hyo-Sook;Kim, Sung-Hee
    • Journal of Nutrition and Health
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    • v.40 no.6
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    • pp.526-530
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    • 2007
  • The purpose of this study was investigating serum lipid, apolipoprotein levels and their correlations in healthy adults of Gyeongnam area. The BMI (body mass index) was significantly higher (p < 0.001) in male (25.2 ${\pm}$ 2.7 $kg/m^2$) than female (23.8 ${\pm}$ 1.5 $kg/m^2$), however PBF (percent body fat) was significantly higher (p < 0.001) in female (29.6 ${\pm}$ 4.3%) than male (22.7 ${\pm}$ 5.0%). The WHR (waist to hip ratio) and blood pressure in the groups showed there was no significant differences. The levels of serum total cholesterol, LDL-cholesterol and apolipoprotein B were significantly higher (p < 0.01) in male (208.7 ${\pm}$ 27.7 mg/dl, 129.0 ${\pm}$ 26.9 mg/dl, 1.0 ${\pm}$ 0.2 g/L) than female (193.6 ${\pm}$ 29.1 mg/dl, 112.5 ${\pm}$ 29.5 mg/dl, 0.9 ${\pm}$ 0.2 g/L, but HDL-cholesterol level was significantly higher (p < 0.01) in female (54.9 ${\pm}$ 6.6 mg/dl) than male (49.9 ${\pm}$ 7.3 mg/dl). The LDL-C/HDL-C, Apo B/Apo A-I and AI (atherogenic index) were significantly higher (p < 0.001) in male (2.6 ${\pm}$ 0.6, 0.8 ${\pm}$ 0.2, 3.3 ${\pm}$ 0.7) than female (2.1 ${\pm}$ 0.5, 0.6 ${\pm}$ 0.2, 2.6 ${\pm}$ 0.5). The triglyceride level was positively correlated with apolipoprotein B concentration (p < 0.05) and negatively correlated with HDL-cholesterol concentration (p < 0.05), however no significant correlation was found with apolipoprotein A-I. According to these results, we conclude that male adults are expecting higher incidence of cardiovascular disease than female adults and we suggest the serum triglyceride should be kept normal level for the prevention of these diseases.

Association between dietary sodium intake and disease burden and mortality in Koreans between 1998 and 2016: The Korea National Health and Nutrition Examination Survey

  • Park, Clara Yongjoo;Jo, Garam;Lee, Juhee;Singh, Gitanjali M.;Lee, Jong-Tae;Shin, Min-Jeong
    • Nutrition Research and Practice
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    • v.14 no.5
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    • pp.501-518
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    • 2020
  • BACKGROUND/OBJECTIVES: Sodium intake is positively associated with blood pressure, which may increase the risk for cardiovascular disease (CVD). Therefore, we assessed the disease burden of CVD attributable to sodium intakes above 2,000 mg/day and prospectively investigated the association between dietary/urinary sodium levels and the risk of all-cause and CVD-mortality using the Korea National Health and Nutrition Examination Survey (KNHNES). SUBJECTS/METHODS: A total of 68,578 and 33,113 participants were included for comparative risk assessment (CRA) analysis and mortality analysis, respectively, and mean follow-up time for mortality was 5.4 years. CRA analysis was used to quantify attributable incidences of stroke, ischemic heart disease (IHD), and deaths attributable to sodium intake between 1998 and 2016. Cox proportional hazard regression model was used to determine the association between sodium intake and all-cause and CVD-mortality. RESULTS: Mean dietary sodium intake decreased over time, reaching 3,647 mg/day in 2016. Similarly, the population attributable fractions of stroke and IHD, and the number of CVD-associated deaths attributable to high sodium intake/excretion also decreased. In terms of association with mortality, when participants were grouped into quartiles (Q) by energy-adjusted sodium intake, those in Q2 had a lower risk of all-cause mortality than those in Q1 with lower intakes. The risk of CVD-associated mortality was higher only in females with high sodium intake in Q4 than those in Q1. CONCLUSIONS: This nationwide data indicates that, in line with previous studies of multiple cohorts, both low and high sodium intakes may be associated with an increased risk of mortality; therefore, the optimal sodium intake for Koreans needs to be revised.