• Title/Summary/Keyword: beta-function

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Use of Beta-Polynomial Approximations for Variance Homogeneity Test and a Mixture of Beta Variates

  • Ha, Hyung-Tae;Kim, Chung-Ah
    • Communications for Statistical Applications and Methods
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    • v.16 no.2
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    • pp.389-396
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    • 2009
  • Approximations for the null distribution of a test statistic arising in multivariate analysis to test homogeneity of variances and a mixture of two beta distributions by making use of a product of beta baseline density function and a polynomial adjustment, so called beta-polynomial density approximant, are discussed. Explicit representations of density and distribution approximants of interest in each case can easily be obtained. Beta-polynomial density approximants produce good approximation over the entire range of the test statistic and also accommodate even the bimodal distribution using an artificial example of a mixture of two beta distributions.

Development of TGF-$\beta$ Resistance During Malignant Progression

  • Kim, Yong-Seok;Yi, Young-Suk;Choi, Shin-Geon;Kim, Seong-Jin
    • Archives of Pharmacal Research
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    • v.22 no.1
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    • pp.1-8
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    • 1999
  • Transforming growth factor-$\beta$ (TGF-$\beta$) is the prototypical multifunctional cytokine, participating in the regulation of vital cellular activities such as proliferation and differentiations as well as a number of basic physiological functions. The effects of TGF-$\beta$ are critically dependent on the expression and distribution of a family of TGF-$\beta$ receptors, the TGF-$\beta$ types I, II, and III. It is now known that a wide variety of human pathology can be caused by aberrant expression and function of these receptors. the coding sequence of the type II receptor (RII) appears to render it uniquely susceptible to DNA replication errors in the course of normal cell division. By virtue of its key role in the regulation of cell proliferation, TGF-$\beta$ RII should be considered as a tumor suppressor gene. High levels of mutation in the TGF-$\beta$ RII gene have been observed in a wide range of primarily epithelial malignancies, including colon and gastric cancer. It appears likely that mutation of the TGF-$\beta$ RII gene may be a very critical step in the pathway of carcinogenesis.

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Some New Hilbert Type Inequalities

  • Salem, Shaban Raslan
    • Kyungpook Mathematical Journal
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    • v.46 no.1
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    • pp.19-29
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    • 2006
  • In this paper, we obtain some inequalities similar to Hilbert type. Some new inequalities are also given.

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Superresolution of Optical Imaging System (광결상계의 초분해능)

  • 조영민;김종태;이상수
    • Korean Journal of Optics and Photonics
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    • v.5 no.3
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    • pp.349-355
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    • 1994
  • Superrsolution of an optical imaging system, which resolves $\epsilon_O$ (half width of the square top amplitude impulse function) less than the Rayleigh's resolution limit $\epsilon_R$, is theoretically treated by using the diffraction theory, and an experimental system is proposed. Initially superresolution is stated as an inverse problem, and an integral equation is derived as a function of parameter $\beta$, which is positive. The integration is numerically carried out for the given aperture and those given values of $\beta$, which is 1, 5, 10, 15, and 20. 1/2$\times$FWHM's of the amplitude impulse functions are meassured for the cases of diffrent value of {J and in the case of $\beta=5$, the half-width already approaches to $\epsilon_O=0.1$,urn, which is, in the case of the present work, one fifth of the Rayleigh's resolution limit. It is found both the pupil function and the phase of the Huygens wave are to be modified, and theories of the pupil function modulation plate and the phase modulation hologram plate are also presented. The result obtained may be useful in ultrafine optical lithography.graphy.

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The Effects of Salvia Miltiorrhiza on Renal Function and Histopathological Changes in Streptozotocin-induced Diabetic Nephropathy Rat Model (단삼이 당뇨병성 신병증 Rat의 신기능 및 조직학적 변화에 미치는 영향)

  • Kim, Young-Seok;Lee, Byung-Cheol;Ahn, Se-Young;Doo, Ho-Kyung;Ahn, Young-Min
    • The Journal of Internal Korean Medicine
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    • v.29 no.3
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    • pp.787-799
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    • 2008
  • Objective : Diabetic nephropathy is the most common cause of end stage renal disease. AGE, $TGF-{\beta}1$ type IV collagen, and macrophage/monocyte infiltration are the main factors of diabetic nephropathy. We investigated the effects of Salvia miltiorrhiza on renal function and histopathological changes in streptozotocin(STZ)-induced diabetic nephropathy rat model. Methods : Diabetes was induced in male Sprague-Dawley rats(290${\pm}$10g) by injecting STZ(45mg/kg) into the tail vein. Rats were divided into 3 groups(n = 6): normal, control, and salvia. After 8 weeks of administration of Salvia miltiorrhiza extract on the Salvia group, we checked 24 hrs urine, blood biochemistry and renal tissue to evaluate renal function and histopathological changes by examining parameters including albuminuria, BUN, creatinine, cholesterol, LDL, TG, macrophage/monocyte antigen(ED-1), $TGF-{\beta}1$, AGE, and type IV collagen. Results : Salvia miltiorrhiza decreased the amount of 24hrs proteinuria, and inhibited histopathological changes of diabetic nephropathy including the expression and accumulation of various factors which could promote development of diabetic nephropathy. Conclusion : These findings suggest that Salvia miltiorrhiza might protect the renal function and inhibit the development of renal injury by regulating factors including AGE, $TGF-{\beta}1$ Type IV collagen, macrophage and monocyte infiltration. So Salvia miltiorrhiza can be used for diabetic patients to prevent the progression of diabetic nephropathy.

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Relationship between Visceral Adiposity Index, Insulin Resistance and Pancreatic Beta Cell Function According to the Prevalence of Metabolic Syndrome in Korean Obese Adults (한국 비만성인의 대사증후군 유병에 따른 내장지방지수와 인슐린저항성, 췌장 베타세포기능과의 관련성)

  • Shin, Kyung-A
    • Journal of the Korea Convergence Society
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    • v.11 no.9
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    • pp.267-276
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    • 2020
  • The purpose of this study was to investigate the relationship between VAI, insulin resistance, and pancreatic beta cell function according to the prevalence of metabolic syndrome in obese adults. From 2017 to 2019, 1,797 obese adults who received medical checkups at a general hospital in Bundang. Diagnosis of metabolic syndrome is NCEP-ATP III. HOMA index was used for insulin resistance and pancreatic beta cell function. VAI was higher in the metabolic syndrome than in the control(p<.001). As the number of risk factors for metabolic syndrome increased, the VAI value was higher(p<.001). The prevalence of metabolic syndrome increased as the VAI quartile increased(p<.001). VAI was also shown to be related to HOMA-IR and HOMA-β in the control, but not in the metabolic syndrome.

Predicting Harvest Maturity of the 'Fuji' Apple using a Beta Distribution Phenology Model based on Temperature (온도기반의 Beta Distribution Model 을 이용한 후지 사과의 성숙기 예측)

  • Choi, In-Tae;Shim, Kyo-Moon;Kim, Yong-Seok;Jung, Myung-Pyo
    • Journal of Environmental Science International
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    • v.26 no.11
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    • pp.1247-1253
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    • 2017
  • The Fuji variety of apple, introduced in Japan, has excellent storage quality and good taste, such that it is the most commonly cultivated apple variety in Gunwi County, North Gyeongsang Province, Korean Peninsula. Accurate prediction of harvest maturity allows farmers to more efficiently manage their farm in important aspects such as working time, fruit storage, market shipment, and labor distribution. Temperature is one of the most important factors that determine plant growth, development, and yield. This paper reports on the beta distribution (function) model that can be used to simulate the the phenological response of plants to temperature. The beta function, commonly used as a skewed probability density in statistics, was introduced to estimate apple harvest maturity as a function of temperature in this study. The model parameters were daily maximum temperature, daily optimum temperature, and maximum growth rate. They were estimated from the input data of daily maximum and minimum temperature and apple harvest maturity. The difference in observed and predicted maturity day from 2009 to 2012, with optimal parameters, was from two days earlier to one day later.

Selective Cleavage of 2,2,2-Trichloroethyl Group with Zinc Dust in the Presence of Phthalimido Function (Phthalimido기 존재하에서 Zinc Dust에 의한 2,2,2-Trichloroethyl 기의 선택적 환원분해)

  • Chung Bong Young;Kim Young-Hwan
    • Journal of the Korean Chemical Society
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    • v.23 no.3
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    • pp.175-179
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    • 1979
  • In acidic media such as aqueous acetic acid, phthalimide is reduced with zinc dust to give 3-hydroxyphthalimidine while the 2,2,2-trichloroethyl esters or glycosides are reductively cleaved. However, it has been discovered that, by employing a mixture of THF and pH 4.5 buffer solution as a solvent, 2,2,2-trichloroethyl group can be selectively removed with activated zinc dust in the presence of phthalimido function, provided that the reactant or the product does not have any free carboxylic acid function. By applying the above methods, reaction of $2,2,2-trichloroethyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-{\beta}-D-glucopyranoside$ (1) with activated zinc dust gave a good yield of $3,4, 6-tri-O-acetyl-2-deoxy-2-phthalimido-{\beta}-D-glucopyranose$ (5) in THF-buffer solution, and $3,4,6-tri-O-acetyl-2-deoxy-2-(3-hydroxyphthalimidino)-{\beta}-D-glucopyranose$ (6) in aqueous acetic acid.

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Comparative Study of Immune-Enhancing Activity of Crude and Mannoprotein-Free Yeast-Gluean Preparations

  • Kim, Hye-Nam;Lee, Jung-Nam;Kim, Gi-Eun;Ha-Lee, Young-Mie;Kim, Chan-Wha;Sohn, Jeong-Won
    • Journal of Microbiology and Biotechnology
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    • v.9 no.6
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    • pp.826-831
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    • 1999
  • ${\beta}-Glucan$, one of the major cell wall components of Saccharomyces cerevisiae, is known to enhance the immune function, especially by activating macrophages. Accordingly, in an effort to develop a safe and efficient immune stimulatory agent, we prepared crude ${\beta}-glucan$ (glucan-p1) and partially purified ${\beta}-glucan$ that was free of mannoproteins (glucan-p2), and evaluated their effect on both the macrophage function and resistance to E. coli-induced peritonitis. To investigate the function of the macrophages, phagocytosis, $TNF-{\alpha}$ secretion, oxygen burst, and the expression of cytokine genes such as $IFN-{\gamma}$ and IL-12 were analyzed. Glucan-p2 markedly stimulated the macrophages with all these parameters. Glucan-p1, however, did not stimulate phagocytosis, yet it induced $TNF-{\alpha}$ secretion, oxygen burst, and the expression of $IFN-{\gamma}$ and IL-12, although less efficiently than glucan-p2. Finally, to test the in vivo protective effect of {\beta}-glucan against infection, the survival of mice from E. coli-induced peritonitis was investigated. After 24 h of the peritoneal challenge of E. coli, all of the mice treated with glucan-p2 survived whereas none survived in the control group. Glucan-p1 showed only a marginal effect in protecting the mice. These results suggest that mannoprotein-free gluean-p2, but not gluean-p1, can serve as an effective immune-stimulating agent.

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Moderate diet-induced weight loss is associated with improved insulin sensitivity in middle-aged healthy obese Korean women

  • Lee, Hye-Ok;Yim, Jung-Eun;Kim, Young-Seol;Choue, Ryowon
    • Nutrition Research and Practice
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    • v.8 no.4
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    • pp.469-475
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    • 2014
  • BACKGROUND/OBJECTIVE: The goal of the present study was to investigate the effects of moderate caloric restriction on ${\beta}$-cell function and insulin sensitivity in middle-aged obese Korean women. SUBJECTS/METHODS: Fifty-seven obese pre-menopausal Korean women participated in a 12-week calorie restriction program. Data on total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), and fasting serum levels of glucose, insulin, C-peptide, blood pressure, leptin and anthropometrics were collected. A dietary intake assessment was based on three days of food recording. Additionally, ${\beta}$-cell function [homeostasis model assessment of ${\beta}$-cell (HOMA-${\beta}$), insulinogenic index (ISI), C-peptide:glucose ratio, and area under curve insulin/glucose ($AUC_{ins/glu}$)] and insulin sensitivity [homeostasis model assessment for insulin resistance (HOMA-IR), Quantitative insulin-sensitivity check index (QUICKI) and Matsuda index (MI)] were recorded. RESULTS: When calories were reduced by an average of 422 kcal/day for 12 weeks, BMI (-2.7%), body fat mass (-10.2%), and waist circumference (-5%) all decreased significantly (P < 0.05). After calorie restriction, weight, body fat percentage, hip circumference, BP, TC, HDL-C, LDL-C, plasma glucose at fasting, insulin at fasting and 120 min, $AUC_{glu}$ and the insulin area under the curve all decreased significantly (all P < 0.05), while insulin sensitivity (HOMA-IR, QUICKI and Matsuda index) measured by OGTT improved significantly (P < 0.01). CONCLUSIONS: Moderate weight loss due to caloric restriction with reduction in insulin resistance improves glucose tolerance and insulin sensitivity in middle-aged obese women and thereby may help prevent the development of type 2 diabetes mellitus.