• Title/Summary/Keyword: human reproduction

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Development of Compliance Emulator System (콤플라이언스 에뮬레이터 시스템의 개발)

  • Park, Chan-Won;Shin, Young-kyun
    • Journal of Industrial Technology
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    • v.19
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    • pp.351-359
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    • 1999
  • If the tactile sense is introduced to engineering and industries, it may provide more realistic virtual tactile sensing to human and it is possible to develop product that satisfy various consumer's taste. This paper presents a compliance emulator system as a new concept of tactile reproduction simulator which uses magnetic levitation in order to minimize friction and emulates compliance only along the vertical direction. Compliance is one of the important mechanical properties of the object related to tactile sensing of the human. The implemented system equipped with an analog LVDT sensor for a position sensor and employs a PD control with gravity compensation to emulate the specified compliance. To compensate the limited range of the system, the method of attaching the spring with various magnitude of stiffness to the system is adopted and its preliminary test is performed to confirm the validity of the method.

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Current Status of Xenotransplantation - A Review

  • Lee, J.H.;Moran, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1497-1504
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    • 2001
  • There is emerging interest in using xenotransplantation of porcine cells, tissues and organs for treatment of human illness. This article reviews the current status of xenotransplantation, with particular emphasis on the physiological and immunological barriers to xenotransplantation and genetic manipulations to overcome xenograft rejection. Preliminary success in xenotransplantation therapy for human Parkinson's disease using porcine foetal brain cells is described. Finally the zoonotic dangers of porcine xenotransplantation, most particularly porcine endogenous retroviruses (PERVs), are discussed.

Secretion of Human Growth Hormone from Mammary Gland of Transgenic Mice (형질전환동물의 유선조직으로부터 인간 성장호르몬의 분비)

  • 구덕본;최강덕;정형민;이상민;이경광;이훈택;정길생
    • Korean Journal of Animal Reproduction
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    • v.17 no.4
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    • pp.375-383
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    • 1994
  • The human growth hormone (hGH) gene uder the control of the rat $\beta$-casein promoter gene was designed to produce transgenic mouse expressed hGH gene in only mammary gland. One hundred seventy two eggs microinjected were transferred to the oviducts of pseudopregnants and 43 offspring were delivered. By Southern blotting hybridization, 3 were transgenic with rat $\beta$-casein/hGH gene. The copy numbers of three transgenic founder were 1, 5, and 15, respectively. A radioimmunoassay was developed to quantitate the amount of expression of the hGH gene in mammary gland of transgenic mice. The amount of hGH was 13.3ng/ml in the lactating milk of one transgenic line, showing predominantly higher than 3.0ng/ml in milk of control mice. Therefore, our findings suggested that $\beta$-casein promoter may induce the tissue specific expression of structural gene.

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Corresponding Color Reproduction on CRT between Illuminated Environment viewing Conditions (관찰환경에 따른 소프트카피의 대응적 색재현)

  • 곽한봉;안성아;서봉우;이영호;안석출
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2001.06a
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    • pp.241-244
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    • 2001
  • A various color device became generalization. Therefore, request about expression of correct color is increased. Device independent color reproduction system acquires and reproduce color of object regardless characteristic of Input/Output device. Human visual system is partially adapted to the CRT monitor's white point and the ambient light. The visual experiments were performed on the effect of the ambient lighting under mixed chromatic adaptation. In this paper, It was found that human visual system is 40% to 60% adapted to CRT monitor's white point light and the rest to ambient light.

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Minipigs as Laboratory Animals: Facility Management and Husbandry

  • Koo, Ok-Jae;Jang, Goo;Lee, Byeong-Chun
    • Reproductive and Developmental Biology
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    • v.36 no.1
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    • pp.79-85
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    • 2012
  • Minipigs are regarded as one of the most important laboratory animal in that anatomical and physiological properties are similar to human and their reproduction efficiency is relatively higher compared to other large animal species. Particularly, several diseases that cannot be mimicked in rodent models are successfully occurred or induced in pig models therefore it has been interested in a valuable model for human diseases. Pigs are also 'standard' species in xenotransplantation research. To maximize experimental outcome using minipigs, establishment and management of proper animal facility, right animal husbandry and control of pathogens are very important. In this review, we summarized several international guidelines related with minipigs published by several companies or governments and discuss optimal conditions for providing informative ideas to the researchers who want to use minipigs in their future studies.

Estimation of Spectral Radiant Distribution of Illumination and Corresponding Color Reproduction According to Viewing Conditions (광원의 분광 방사 분포의 추정과 관찰조건에 따른 대응적 색재현)

  • 방상택;이철희;곽한봉;유미옥;안석출
    • Proceedings of the Korean Printing Society Conference
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    • 2000.04a
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    • pp.35-44
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    • 2000
  • Because Image on the CRT change under different illuminants, human is difficult to see original color of object. If what is information of used illuminant on capturing object know, image can be transformed according to viewing condition using the linear matrix method. To know information of used illuminant at an image, the spectral radiance of illuminant can be estimated using the linear model of Maloney and Wandell form an image. And then image can be properly transformed it using color appearance model. In this paper, we predict the spectral radiance of illuminant using spectral power distribution of specular light and using surface spectral reflectance at maximum gray area. and then we perform visual experiments for the corresponding color reproduction according to viewing condition. In results, we ensure that the spectral radiance of illuminant at an image can be well estimated using above algorithms and that human visual system is 70% adapted to the monitor's white point and 30% to ambient light when viewing softcopy images.

Identification of matrix metalloproteinases secreted by human hepatocarcinoma HepG2 cells

  • Lee, Young Jae;Kim, Keun Cheon;Lim, Jeong Mook;Lee, Seung Tae
    • Journal of Animal Reproduction and Biotechnology
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    • v.37 no.1
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    • pp.62-66
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    • 2022
  • To date, the development of anticancer drugs has been conducted using two-dimensional (2D) cell culture systems. However, since cancer cells in the body are generated and developed in three-dimensional (3D) microenvironments, the use of 2D anticancer drug screening can make it difficult to accurately evaluate the anticancer effects of drug candidates. Therefore, as a step towards developing a cancer cell-friendly 3D microenvironment based on a combination of vinylsulfone-functionalized polyethylene glycol (PEG-VS) with dicysteine-containing crosslinker peptides with an intervening matrix metalloproteinase (MMP)-specific cleavage site, the types of MMPs secreted from human hepatocarcinoma HepG2 cells, a representative cancer cell, were analyzed transcriptionally and translationally. MMP3 was confirmed to be the most highly expressed protease secreted by HepG2 cells. This knowledge will be important in the design of a crosslinker necessary for the construction of PEG-based hydrogels customized for the 3D culture of HepG2 cells.

Commentary on the new 2022 European Society of Human Reproduction and Embryology (ESHRE) endometriosis guidelines

  • Eun Hee Yu;Jong Kil Joo
    • Clinical and Experimental Reproductive Medicine
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    • v.49 no.4
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    • pp.219-224
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    • 2022
  • Endometriosis is a prevalent benign illness defined by the presence of endometrial glands and stroma outside of the uterine cavity, primarily on the ovary, pelvic peritoneum, and rectovaginal septum, resulting in a variety of symptoms, including dysmenorrhea and infertility. Traditionally, prolonged medical therapy has been needed in most cases since a conservative approach to surgery has usually been taken, especially in young women. In 2022, new European Society of Human Reproduction and Embryology (ESHRE) guidelines were published that present different directions for diagnosis and treatment from the past. Furthermore, the guidelines for the diagnosis and management of endometriosis are more precise and applicable than in previous editions. Thus, referring to the representative changes in the new guidelines and important updates will be beneficial for the diagnosis and management of endometriosis. This paper provides a brief overview of these developments.

Studies on Phenotype of Reproduction and Production of Human Growth Hormone(hGH) with Transgenic Rats II. Different Reproductive Phenotypes Determined by hGH Levels in hGH Transgenic Rats (Human 성장호르몬을 도입한 Transgenic Rats의 작출과 번식표현형에 관한 연구 II. 형질전환된 Rats의 hGH수준이 번식표현형에 미치는 영향)

  • 장규태;김성현;성환후;주학진;박미령;윤창현
    • Korean Journal of Animal Reproduction
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    • v.22 no.2
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    • pp.137-143
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    • 1998
  • The effects of continuous GH(hGH) secretion on the female reproduction was studies in adults female transgenic rats expressing the hGH gene with a mouse whey acid protein (mWAP) promotor. Two line of transgenic female rats carrying the mWAP/hGH gene were established and used in the study. One was characterized by relatively high levels of serum hGH (high line), and the other had relatively low levels (low line). 1. High line female rats had recurring, Pseudopregancy-like estrous cycles accompanied by increased serum progesterone level for 2 weeks after ovulation, and they were fertile. 2. In the rats, luteinization occurred spontaneously without cervical stimulation, probably due to high levels of serum hGH, which has prolactin (PRL)-like activity in the rat. 3. Low line female rats had recurring, regular 4-days estrous PRL surge following cervical stimulation were not, detected and PRL secretion was not induced by a dopamine antagonist. 4. The ovarian tissue in this line had a much higher number of corpora lutea and grew much heavier than in normal littermates, suggesting impairment of PRL induced structural luteolized. Su, pp.ession of PRL secretion in the low line rats was, at least in part, due to a marked decrease in the number of lactotrophs in the pituitary. The present study shows that the serum hGH level plays a crucial role in regulating luteal function in female transgenic rats expressing the hGH gene.

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A Study on the Characteristics of Color Reproduction in Digital Printing (디지털인쇄에서 색재현 특성에 관한 연구)

  • Kim, Jae-Hae;Lee, Sung-Hyung;Cho, Ga-Ram;Koo, Chul-Whoi
    • Journal of the Korean Graphic Arts Communication Society
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    • v.24 no.1
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    • pp.23-34
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    • 2006
  • Color reproduction is one of the most important expression factors in digital printing. In this paper, an experiment was done where the characteristics of color reproduction in digital printing. The results could summarized as follows. The printing used device profile showed a color difference of less than printing used default value in digital printing. As a result of weighting color difference, a difference between color gamut of digital original and color gamut of printing, when transforming the RGB color space to CMY color space, a exclusion the gray revision. The solution is to optimize the color transformation by gamut mapping and gray revision.

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