• Title/Summary/Keyword: high Tg

Search Result 894, Processing Time 0.035 seconds

Efficient Verification of X-ray Target Replacement for the C-series High Energy Linear Accelerator

  • Cho, Jin Dong;Chun, Minsoo;Son, Jaeman;An, Hyun Joon;Yoon, Jeongmin;Choi, Chang Heon;Kim, Jung-in;Park, Jong Min;Kim, Jin Sung
    • Progress in Medical Physics
    • /
    • v.29 no.3
    • /
    • pp.92-100
    • /
    • 2018
  • The manufacturer of a linear accelerator (LINAC) has reported that the target melting phenomenon could be caused by a non-recommended output setting and the excessive use of monitor unit (MU) with intensity-modulated radiation therapy (IMRT). Due to these reasons, we observed an unexpected beam interruption during the treatment of a patient in our institution. The target status was inspected and a replacement of the target was determined. After the target replacement, the beam profile was adjusted to the machine commissioning beam data, and the absolute doses-to-water for 6 MV and 10 MV photon beams were calibrated according to American Association of Physicists in Medicine (AAPM) Task Group (TG)-51 protocol. To verify the beam data after target replacement, the beam flatness, symmetry, output factor, and percent depth dose (PDD) were measured and compared with the commissioning data. The difference between the referenced and measured data for flatness and symmetry exhibited a coincidence within 0.3% for both 6 MV and 10 MV, and the difference of the PDD at 10 cm depth ($PDD_{10}$) was also within 0.3% for both photon energies. Also, patient-specific quality assurances (QAs) were performed with gamma analysis using a 2-D diode and ion chamber array detector for eight patients. The average gamma passing rates for all patients for the relative dose distribution was $99.1%{\pm}1.0%$, and those for absolute dose distribution was $97.2%{\pm}2.7%$, which means the gamma analysis results were all clinically acceptable. In this study, we recommend that the beam characteristics, such as beam profile, depth dose, and output factors, should be examined. Further, patient-specific QAs should be performed to verify the changes in the overall beam delivery system when a target replacement is inevitable; although it is more important to check the beam output in a daily routine.

Relationship between Psychosocial Stress and Coronary Risk Factors of Employees in a Research Institute (일부 남성 연구원들의 사회심리적 스트레스와 관상동맥질환 위험인자의 관련성)

  • Park, Chun-Ja;Kwon, In-Sun;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.11 no.1
    • /
    • pp.392-401
    • /
    • 2010
  • The purpose of the present study was intended to assess psycosocial stress of male researchers working in a Research Institute, and to reveal the relationship between psycosocial stress and coronary risk factors. Data were obtained from 356 male researchers who underwent health package check-up at the health promotion center of a university hospital from May to June 2007, using by self-administered questionnaire & health check-up. For psycosocial stress, we used the questionnaire with 18 items developed as Psychosocial Well-bing Index(PWI). For coronary risk factors, systolic and diastolic blood pressure(SBP, DBP), triglyceride(TG), total cholesterol(TC), high and low density lipoprotein cholesterol(HDL, LDL), fasting blood sugar(FBS) and % fat rate were measured. As a results, the level of psycosocial stress is influenced by socio-demographic characteristics, job-related characteristics and health-related behaviors. Especially, it was found to have the inter-relational effects that the higher the blood pressure, the higher the level of psycosocial stress.

Development of Packaging Materials for MA Packaging(1) (MA포장용 기능성 포장 소재개발에 관한 연구(1))

  • Park, Hyung-Woo;Park, Moo-Hyun;Kim, Hoon;Lee, Jae-Young;Yang, Han-Chul
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.3 no.2
    • /
    • pp.25-31
    • /
    • 1996
  • Various treaments such heating, acid tenting, acid healing, alkaline treating, acid+alkaline renting were attempted to investigate their effects on molar ratio, chemical composition, DTA and specific surface area(SSA) of natural zeolite poder. Molar ratio, Si to AI. of natural zeolite was 4.78, which represented high silica type. Composition of natural zeolite showed that $SiO_2$ was 66.34% $Al_2O_3$ was 13.89%, $Fe_2O_2$ was 1.55% X-ray diffraction showed that main component of natural zeolite was mordenite and clinoptliolite. Differential Thermal Analysis and Thermogravimetry curve of natural zeolite was showed to peak of endothermic peak at $80^{\circ}C$ and it means to the peak of dehydrate reaction, but recristalization was not formed below at $1,000^{\circ}C$. Weight loss during calcination was 16% at $1,000^{\circ}C$. Thermal treatments on SSA of natural zolite powder decreased from $75.2m^2/g\;to\;2.1m^2/g$. In contrast chemical treatments on SSA showed to increase to $300.2m^2/g$(1 N HCl treating), $54.9m^2/g$(1 N NaOH) and $90.9m^2/g$(HCl+NaOH)tudy, it could be proposed to employ acid tret method as packaging materisls for MA packaging.

  • PDF

A Case Report of Diabetic Hyperlipidemia in a Patient with Cerebral Infarction Treated with Ojeok-san (뇌경색 환자의 당뇨병성 고지혈증에 대한 오적산가감방(五積散加減方) 호전 1례)

  • Han, Seung-Hea;Jeong, Byeong-Ju;Woo, Sung-Ho;Kim, Byung-Chul;Kim, Yong-Ho;Seo, Ho-Seok;Hwang, Gyu-Dong;Cho, Cheol-Jun;Nam, Hyo-Ick;Kim, Jin-Won
    • The Journal of Internal Korean Medicine
    • /
    • v.26 no.1
    • /
    • pp.275-280
    • /
    • 2005
  • Hyperlipidemia is one of the major factors causing the atherosclerosis of coronary arteries and well-documented modifiable risk factors of stroke, especially of the ischemic type. For Insulin-Dependent Diabetes Mellitus sufferers, if blood sugar is appropriately maintained, lipid and lipoprotein are normal, but if blood sugar is inappropriately maintained or clinical Diabetic nephropathy induces metabolic disorder of lipid, then Total cholesterol, low density lipoprotein cholesterol, triglyceride and very low density lipoprotein cholesterol levels go up and high density lipoprotein levels go down. The purpose of this study is to evaluate the effect of treatment with Ojeok-san and to observe the changes in Fasting Blood Sugar(FBS), 2 Hours Postprandial Blood Sugar(PP2h), Haemoglobin A1c(HbA1c), Total Cholesterol(T-Chol) and Triglyceride(TG). After the treatment, Fasting Blood Sugar decreased from 149mg/dl to 89mg/dl. 2 Hours Postprandial Blood Sugar decreased from l85mg/dl to 110mg/dl. Haemoglobin A1c decreased from 6.3% to 5.7%. Total Cholesterol decreased from 268mg/dl to 217mg/dl. And Triglyceride decreased from 438mg/dl to 265mg/dl. These results support a role for oriental medical therapy in treating Diabetic Hyperlipidemia. Further case studies of herbal treatment of this ailment are needed.

  • PDF

Effects of Salt and Precursor pH on Synthesizing Behavior and Grain Morphology of Mullite in Aqueous System (수용성 매체에서 뮬라이트의 합성거동 및 입자형상에 미치는 염 및 전구체 pH의 영향)

  • Jung, Yeon-Gil;Lee, Jae-Ean;Shin, Young-Ill;Kim, Jae-Won;Jo, Chang-Yong
    • Korean Journal of Materials Research
    • /
    • v.13 no.4
    • /
    • pp.251-258
    • /
    • 2003
  • The effects of the salt and the precursor pH on the synthesizing behavior and the morphology of mullite have been studied. Two kinds of mullite precursor sols were prepared by the dissolution of two kinds of salt (aluminum nitrate enneahydrate, Al($NO_3$)$_3$$9H_2$O; type I and aluminum sulfate 14∼18 water, (SO$Al_4$)$_3$$\cdot$$14∼18H_2$O; type II) into the mixture of colloidal silica sol, respectively. Precursor pH of the sols was controlled to the acidic (pH= 1.5∼2) and basic (pH= 8.5∼9) conditions. The co-products with nitrate and sulfate were completely eliminated at $500^{\circ}C$ and $850^{\circ}C$, respectively, which was confirmed by TG/DTA results. The synthesizing temperature of mullite phase was found to be above $1200^{\circ}C$ for pH= 1.5∼2 and above $1300^{\circ}C$ for pH= 8.5∼9 in type I. However, in type II, the synthesizing temperature of mullite was decreased to $850^{\circ}C$ for pH= 1.5∼2 and $1100^{\circ}C$ for pH= 8.5∼9. The grain size of the mullite synthesized at pH= 8.5∼9 was larger than that at pH= 1.5∼2 in overall heat-treated temperatures, showing smaller grain size in type II. Aspect ratio of the mullite grains was more increased at pH= 1.5∼2 than pH= 8.5∼9 in type I, showing similar aspect ratio at both pH conditions in type II. It was found that the synthesizing temperature and grain size were predominantly governed by the initial precursor pH and decomposition of the salt, with minor effect on the grain morphology.

Comparing validity of using Body Mass Index, Waist to Hip Ratio, and Waist Circumference to Cardiovascular Risk Factors of Middle Aged Koreans (한국중년층에서 체질량지수, 허리-엉덩이둘레비, 및 허리둘레의 심장혈관계질환 위험인자 타당도 비교)

  • Mun, Hyeon-Gyeong;Kim, Yu-Jin
    • Journal of the Korean Dietetic Association
    • /
    • v.11 no.3
    • /
    • pp.365-374
    • /
    • 2005
  • This study was conducted to compare the validity of obese index among body mass index(BMI), waist to hip ratio(WHR), and waist circumference(WC) and to determine which is the best in relation to cardiovascular risk factors of middle aged Korean(40-64yr).Data from the 1998 Korean Health and Nutrition Survey were used(N=3380). Anthropometric indices and cardiovascular risk factors were measured. Chi-square test, analysis of variance following duncan's multiple range test, partial correlation analysis, and Receiver Operator characteristic(ROC) curves were used in the analysis. There was a significant increasing trend in WHR, systolic blood pressure(SBP), high density lipoprotein cholesterol(HDL), and fasting blood sugar(FBS) with age categories of male and in BMI, WC, WHR, diastolic blood pressure(DBP), SBP, total cholesterol(TC), low density lipoprotein cholesterol(LDL), triglycerol(TG), and FBS with those of female. Specially female had the characteristics of upper body fat and systolic blood pressure risk(p<0.05). Proportions of subjects with lifestyle factors related to cardiovascular risk in overweight or upper body fat group were higher than that of normal group. Higher proportions of subjects were practiced exercise in upper body fat group of male than in other groups. Among 7 cardiovascular risk factors in partial correlation analysis, BMI had the highest correlation coefficient in 6 risk factors in male, whereas WC in 4 risk factors in female. Mean of each obese index according to cardiovascular risk groups except smoker was higher than that of normal(p<0.05). These trends were shown in upper body fat group and female. In ROC analysis of 12 risk factors and health conditions, the largest area under curve among obese indices for risk factors were BMI in male and WHR in female. The optimal cutoff values of each index(BMI: WHR: WC) for one or more cardiovascular risk factors were 23.13: 0.89: 85.35 in male and 23.57: 0.84: 78.35 in female. The results showed that cardiovascular risk factors were prevalent in middle aged Koreans within normal limits of obese indices like another Asians. For the identification of cardiovascular risk factors of middle aged Koreans, BMI for men and WHR for women are appropriate indices. But it is recommended that BMI, WHR, and WC, all three indices should be considered, when using these indices.

  • PDF

1-Deoxynojirimycin Content and Blood Glucose-Lowering Effect of Silkworm (Bombyx mori) Extract Powder

  • Ryu, Kang-Sun;Lee, Heui-Sam;Kim, Kee-Young;Kim, Mi-Ja;Sung, Gyoo-Byung;Ji, Sang-Deok;Kang, Pil-Don
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.27 no.2
    • /
    • pp.237-242
    • /
    • 2013
  • We investigated the 1-deoxynojirimycin (1-DNJ) content of extracts from silkworm larvae at each developmental stage within three silkworm varieties. We also compared the content of the following polyhydroxylated alkaloids in the silkworm extracts: 1-DNJ, fagomine, and 1,4-dideoxy-1,4-imino-d-arabinitol (DAB). In addition, we evaluated the glucose-lowering effects of silkworm extract powder in db/db mice. The 1-DNJ content was the highest in Yeonnokjam $5^{th}$ instar $3^{rd}$ d larvae and Hansaengjam $5^{th}$ instar $3^{rd}$ d larvae, which contained 18.4 mg/100 g dry weight and 18.3 mg/100 g dry weight, respectively. The $5^{th}$ instar $3^{rd}$ d larvae exhibited a higher content of 1-DNJ than that of $5^{th}$ instar $5^{th}$ d larvae among all varieties. The glucose-lowering effects of silkworm extracts and Yeonnokjam powder were tested on db/db mice, and the blood glucose levels were found to decrease significantly in the YR70 group. Silkworm extracts (180 mg/kg, 90 mg/kg, 45 mg/kg, and 22.5 mg/kg) and acarbose (50 mg/kg) were administered orally for 4 wk. Changes in water intake were not statistically significant between control and silkworm extract-treated groups. Compared to the control group, blood glucose levels in the silkworm extract powder-treated group decreased in the 22.5 mg/kg/d group after being administered for 4 wk. This decrease was statistically significant. Furthermore, biochemical changes in the AST(Aspartate aminotransferase), ALT(Alanine aminotransferase), TCHO(Total Cholesterol), TG(Triglyceride), LDL(Low density lipoprotein), and HDL(High density lipoprotein) levels in blood were not observed. However, statistically significant decreases in blood GLU in the 22.5 mg/kg/d group compared to that of the control group occurred. In addition, the epididymal fat weight of the silkworm extract powder-treated group decreased significantly in both the 22.5 mg/kg/d group and 180 mg/kg/d group compared to that of the control group, but there were no statistically significant changes in perirenal fat weight. These results demonstrate that silkworm extracts inhibit changes in blood glucose levels in model diabetic mice.

The Effect of Auricular Acupuncture for Obesity: A Systematic Review and Meta-analysis (비만치료에 대한 이침요법의 효과에 대한 고찰: 체계적 문헌고찰 및 메타분석)

  • Park, Seohyun;An, Sunjoo;Choi, Sunghwan;Kang, Shinwoo;Keum, Dongho
    • Journal of Korean Medicine for Obesity Research
    • /
    • v.20 no.1
    • /
    • pp.52-68
    • /
    • 2020
  • Objectives: The purpose of this study is to investigate the weight loss effects of auricular acupuncture in obese patients. Methods: Six databases (Research Information Sharing Service [RISS], Korean studies Information Service System [KISS], Oriental Medicine Advanced Searching Integrated System [OASIS], PubMed, The Cochrane Library, China National Knowledge Infrastructure [CNKI]) were searched up to May 20, 2020. Eight eligible randomized controlled trials were included the present study. The quality of included studies was assessed by the Cochrane risk of bias tool and a meta-analysis was performed by Review Manager software. A meta-analysis was conducted using a random-effects model and a subgroup analysis was performed to detect the sources of heterogeneity, identify the selection of acupuncture methods and explore its contributions to the weight loss effects. Results: Among 8 trials, 5 trials used auricular acupuncture and 2 trials used auricular acupressure, 1 trial used both types of intervention. Most commonly selected acupoints were Shenmen (TF4) and stomach (CO4). Treatment duration was six to twelve weeks, and total treatment session was six to twelve. Compared to the control groups, auricular acupuncture significantly decreased body weight, body mass index (BMI), high density lipoprotein-cholesterol (HDL) and ghrelin. For the selection of acupuncture methods, both methods performed similarly in most outcome except waist circumference (WC), body fat percentage (BFP), and triglycerides (TG). Conclusions: We found that auricular acupuncture can be effective for weight loss and controlling appetite. However, the findings should be interpreted with caution due to heterogeneity. So further vigorous and well-designed studies should be conducted to strengthen the evidence of the use of auricular acupuncture for obesity.

Estimating of the Greenhouse Gas Mitigation and Function of Water Resources Conservation through Conservation of Surface Soils Erosion and Policy Suggestion (표토유실 보전을 통한 온실가스배출 저감과 수자원 보전 기능의 산출 및 정책제안)

  • Oh, Seung-Min;Kim, Hyuck Soo;Lee, Sang-Pil;Lee, Jong Geon;Jeong, Seok Soon;Lim, Kyung Jae;Kim, Sung-Chul;Park, Youn Shik;Lee, Giha;Hwang, Sang-Il;Yang, Jae-E
    • Journal of Soil and Groundwater Environment
    • /
    • v.22 no.6
    • /
    • pp.74-84
    • /
    • 2017
  • Soil erosion is often extreme in Korea due to high rainfall intensities and steep slopes, and climate change has also increased the risk of erosion. Despite its significane, erosion-induced soil organic carbon (SOC) emission and water resource loss are not well understood, along with the lack of an integrated surface soil erosion protection policy. Therefore, to design adequate protection policies, land users, scientists, engineers and decision makers need proper information about surface soil and watershed properties related to greenhouse gas emission potential and water conservation capability, respectively. Assuming the total soil erosion of $346Tg\;yr^{-1}$, soil organic matter (SOM) content of 2% (58% of SOM is SOC), and mineralization rate of 20% of the displaced carbon, erosion-induced carbon emission could reach $800Gg\;C\;yr^{-1}$. Also the available water capacity of the soil was estimated to be 15.8 billion tons, which was 14 times higher than the yearly water supply demand in Seoul, Korea. Therefore, in order to prevent of soil erosion, this study proposes a three-stage plan for surface soil erosion prevention: 1) classification of soil erosion risk and scoring of surface soil quality, 2) selection of priority areas for conservation and best management practices (BMP), and 3) application of BMP and post management.

Strain induced/enhanced ferromagnetism in $Mn_3Ge_2$thinfilms

  • Dung, Dang Duc;Feng, Wuwei;Thiet, Duong Van;Sin, Yu-Ri-Mi;Jo, Seong-Rae
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.135-135
    • /
    • 2010
  • In Mn-Ge equilibrium phase diagram, many Mn-Ge intermetallic phases can be formed with difference structures and magnetic properties. The MnGe has the cubic structure and antiferromagnetic(AFM) with Neel temperature of 197 K. The calculation predicted that the $MnGe_2$ with $Al_2Cu$-type is hard to separate between the paramagnetic(PM) states and the AFM states because this compound displays PM and AFM configuration swith similar energy. Mn-doped Ge showed the FM with Currie temperature of 285 K for bulk samples and 116 K for thin films. In addition, the $Mn_5Ge_3$ compound has hexagonal structure and FM with Curie temperature around 296K. The $Mn_{11}Ge_8$ compound has the orthorhombic structure and Tc is low at 274 K and spin flopping transition is near to 140 K. While the bulk $Mn_3Ge_2$ exhibited tetragonal structure ($a=5.745{\AA}$;$c=13.89{\AA}$) with the FM near to 300K and AFM below 150K. However, amorphous $Mn_3Ge_2$ ($a-Mn_3Ge_2$) was reported to show spin glass behavior with spin-glass transition temperature (Tg) of 53 K. In addition, the transition of crystalline $Mn_3Ge_2$ shifts under high pressure. At the atmospheric pressure, $Mn_3Ge_2$ undergoes the magnetic phase transition from AFM to FM at 158 K. The pressure dependence of the phase transition in $Mn_3Ge_2$ has been determined up to 1 GPa. The transition was found to occur at 1 GPa and 155 K with dT/dP=-0.3K/0.1 GPa. Here report that Ferromagnetic $Mn_3Ge_2$ thin films were successfully grown on GaAs(001) and GaSb(001) substrates using molecular beam epitaxy. Our result revealed that the substrate facilitates to modify magnetic and electrical properties due to tensile/compressive strain effect. The spin-flopping transition around 145 K remained for samples grown on GaSb(001) while it completely disappeared for samples grown on GaAs(001). The antiferromagnetism below 145K changed to ferromagnetism and remained upto 327K. The saturation magnetization was found to be 1.32 and $0.23\;{\mu}B/Mn$ at 5 K for samples grown on GaAs(001) and GaSb(001), respectively.

  • PDF