• Title/Summary/Keyword: Biological variable

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Sex as an important biological variable in biomedical research

  • Lee, Suk Kyeong
    • BMB Reports
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    • v.51 no.4
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    • pp.167-173
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    • 2018
  • Experimental results obtained from research using only one sex are sometimes extrapolated to both sexes without thorough justification. However, this might cause enormous economic loss and unintended fatalities. Between years 1997 and 2000, the US Food and Drug Administration suspended ten prescription drugs producing severe adverse effects on the market. Eight of the ten drugs caused greater health risks in women. Serious male biases in basic, preclinical, and clinical research were the main reason for the problem. This mini-review will describe why and how funding organizations such as the European Commission, the Canadian Institutes of Health Research, and the US National Institutes of Health have tried to influence researchers to integrate sex/gender not only in clinical research, but also in basic and preclinical research. Editorial policies of prominent journals for sex-specific reporting will also be introduced, and some considerations in integrating sex as a biological variable will be pointed out. To produce precise and reproducible results applicable for both men and women, sex should be considered as an important biological variable from basic and preclinical research.

Relationship among Degree of Time-delay, Input Variables, and Model Predictability in the Development Process of Non-linear Ecological Model in a River Ecosystem (비선형 시계열 하천생태모형 개발과정 중 시간지연단계와 입력변수, 모형 예측성 간 관계평가)

  • Jeong, Kwang-Seuk;Kim, Dong-Kyun;Yoon, Ju-Duk;La, Geung-Hwan;Kim, Hyun-Woo;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.43 no.1
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    • pp.161-167
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    • 2010
  • In this study, we implemented an experimental approach of ecological model development in order to emphasize the importance of input variable selection with respect to time-delayed arrangement between input and output variables. Time-series modeling requires relevant input variable selection for the prediction of a specific output variable (e.g. density of a species). Inadequate variable utility for input often causes increase of model construction time and low efficiency of developed model when applied to real world representation. Therefore, for future prediction, researchers have to decide number of time-delay (e.g. months, weeks or days; t-n) to predict a certain phenomenon at current time t. We prepared a total of 3,900 equation models produced by Time-Series Optimized Genetic Programming (TSOGP) algorithm, for the prediction of monthly averaged density of a potamic phytoplankton species Stephanodiscus hantzschii, considering future prediction from 0- (no future prediction) to 12-months ahead (interval by 1 month; 300 equations per each month-delay). From the investigation of model structure, input variable selectivity was obviously affected by the time-delay arrangement, and the model predictability was related with the type of input variables. From the results, we can conclude that, although Machine Learning (ML) algorithms which have popularly been used in Ecological Informatics (EI) provide high performance in future prediction of ecological entities, the efficiency of models would be lowered unless relevant input variables are selectively used.

Sister chromatid exchange in peripheral lymphocytes of radiation exposed workers in a hospital (방사선 직업 종사자의 자매염색분체교환)

  • Hong, Hae-Sook;Na, Yeon-Kyung;Ha, Sun-Ok;Lee, Jeong-Ran
    • Journal of Korean Biological Nursing Science
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    • v.2 no.2
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    • pp.90-101
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    • 2000
  • This study is being carried out, in two different random sample groups, between 20 men who were radiation exposed workers in the two general hospitals located in "T" city as a experimental group and 20 healthy men who were non-radiation exposed workers as a control group. The occurring frequency of the sister chromatid exchange as a biological dosemeter of radiation were studied. And the age, duration of employment and smoking were used as variable for the experiment. The results are as follows : The frequency of SCE were noticed respectively by each variable : 1) by age as a variable, the frequency were increased notably in radiation exposed workers group rather than a control group(p<0.05). 2) by duration of employment, the difference of the frequency were not recognised significantly in statistical among radiation exposed workers. 3) in smoker the frequency were increased notably in a radiation exposed workers than a control groups(p<0.05). Taking into consideration the above results, the age and smoking could affect the frequency of SCE, however, the size of sample were too small to generalize. Therefore, the following suggestions are recommended to get more accurate result. 1) In order to clarify the correlation in a smoking as variable, finding the volume of smoking and its related factor are necessarily required. 2) In order to confirm the correlation in each variable, adopting of a bigger-sized sample are needed and the study itself also be carried out repeatedly.

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A comparison of photosynthesis measurements by O2 evolution, 14C assimilation, and variable chlorophyll fluorescence during light acclimatization of the diatom Coscinodiscus granii

  • Trampe, Erik;Hansen, Per Juel;Kuhl, Michael
    • ALGAE
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    • v.30 no.2
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    • pp.103-119
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    • 2015
  • Photosynthetic rates of the large centric diatom Coscinodiscus granii were measured by means of multicolor variable chlorophyll fluorescence imaging, single cell $^{14}C$ assimilation, and optical $O_2$ sensor measurements during light acclimatization of cultures grown at five different irradiances: 50, 150, 235, 332, and $450{\mu}mol$ photons $m^{-2}\;s^{-1}$. Photo-acclimatization was evident from changes of cellular chlorophyll a content, growth rates, and light response curves. Each of the applied methods evaluates different parts and reactions in the photosynthetic apparatus, which makes a direct quantitative comparison of rates difficult, although a different degree of correlation were found between all three methods. However, when used in combination, they provide information about the internal relationship of photosynthetic pathways as well as the variation in photosynthetic capacity between individual cells within a single algal culture.

PCR Analysis of Four Length-Polmorphic Loci in Korea Population for Genotyping

  • Ryu, Jae-Song;Koo, Yoon-Mo;So, Jae-Seong
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.3
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    • pp.169-173
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    • 2000
  • On human chromoscomes, a short sequence of DNA is known to repeat a number of times. These are called variable number of tandem repeat (VNTR) or short tandem respeat (STR) which has a short core. VNTR and STR are used in the filed of forensic science, evolution, and anthropology. In this work, we examined allele frequencies of one VNTR (YNZ22) and three STRs (NeuR, D21S11, Humth01) in a korean population sample by polymerase chain reaction (RCP) followed by high-resolution polyacrylamide gel electro-phoresis (PAGE) with silver stain. Subsequently, the polymorphism information content (PIC) was calculated : the hifhest PIC was observed in the NeuR locus (0.95680) and lowest in the Humth01 locus (0.75809).

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A Study on the Compressed Code for Biological Signal (생체신호 데이터의 압축코드 알고리즘에 관한 연구)

  • Hong, Seung-Hong;Son, Chang-Il;Min, Hong-Gi
    • Journal of Biomedical Engineering Research
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    • v.5 no.1
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    • pp.93-102
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    • 1984
  • In this paper, the real-time compressed code generation method for the biological signal data, especially for the Electrocardiogram, is studied. For this purpose, variable length code is introduced. And from this code, we get a exactly the same reconstructed signal data as the original. Experimental results show that this program reduces the data rate by a factor of about 8, and codes the result in a form convenient for analysis.

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Expression of a Functional Anti-Cucumber Mosaic Virus Single-Chain Variable Fragment Antibody in Tobacco Plants (Nacotiana tabacum)

  • Heng Chua Kek;Khalid Norzulaani;Othman Retina Yasmin
    • Journal of Plant Biotechnology
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    • v.8 no.1
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    • pp.9-14
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    • 2006
  • As an alternative method to produce low cost reagents for immunodiagnosis and protect the plants from viral disease, a gene encoding a single chain variable fragment(scFv) recombinant antibody targeted to the coat protein of cucumber mosaic virus (CMV) was expressed in Nacotiana tabacum. The source of the scFv recombinant antibody gene was from spleen tissue of an immunized mouse. The gene was initially cloned into the pCANTAB5E phagemid and expressed in E. coli. In the following study, the antibody gene was subcloned into the plant expression vector, pCAMBIA-1301 and introduced into tobacco leaf tissue via Agrobacterium tumefacients mediated transformation. After transformation, 56 out of 58 plants were shown to carry the desired anti-CMV scFv gene by PCR analysis. Overall, only 12.5% of the 56 putative transgenic plants were found to express the antibody to a detectable level.

Design of Nonlinear PID Controller Based on Immune Feedback Mechanism (면역 피드백 메카니즘에 기초한 비선형 PID 제어기 설계)

  • Park Jin-Hyun;Choi Young-Kiu
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.3
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    • pp.134-141
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    • 2003
  • PID controllers with constant gains have been widely used in various control systems due to its powerful performance and easy implementation. But it is difficult to have uniformly good control performance in all operating conditions. In this paper, we propose a nonlinear variable PR controller with immune feedback mechanism. An immune feedback mechanism is based on the functioning of biological T-cells, they include both an active term, which controls response speed. and an inhibitive term, which controls stabilization effect. Therefore, the proposed nonlinear PID controller is based on immune responses of biological. immune feedback mechanism which is the cell mediated immunity and In order to choose the optimal nonlinear PID controller games, we also propose the tuning algorithm of nonlinear function parameter in immune feedback mechanism. To verify performance of the proposed algorithm, the speed control of nonlinear DC motor are performed. Front the simulation results, we have found that the proposed algorithm is more superior to the conventional constant fain PID controller.

Studies on the stability examination of biological products - BCG vaccine

  • Lee, Joo-Hyeun;Shin, Won-Pil;Ahn, Hye-Jeong;Kim, So-Hee;Lee, Gil-Woong
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.180.3-180.3
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    • 2003
  • This study was carried out to examine stability of biological products(BCG vaccine), freeze-dried BCG vaccine for percutaneous use and for interdermal use.1. pH tests of freeze-dried BCG vaccine for percutaneous use and for interdermal use vaccine was suited to basic range with variable temperature. freeze-dried BCG vaccine for percutaneous use was resulted with 6.2-6.7 and for interdermal use was resulted with 6.2-6.7.2. Bacterial concentration test of freeze-dried BCG vaccine for percutaneous use and for interdermal use vaccine was suited to basic range with variable temperature. (omitted)

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The Relative Biological Effectiveness of KCCH-Cyclotron neutron (원자력병원(原子力病院) 싸이클로트론 속중성자선(速中性子線)의 방사선생물학적효과비(RBE)에 관(關)한 연구(硏究))

  • Yoo, Seong-Yul;Koh, Kyoung-Hwan;Cho, Chul-Koo;Kim, Sung-Ho
    • Journal of Radiation Protection and Research
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    • v.12 no.2
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    • pp.1-8
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    • 1987
  • The relative biological effectiveness has been measured for the biological characterization of $p^+(50.5\;MeV)$ Be neutron of KCCH-Cyclotron prior to clinical application. Measured RBE of mouse jejunal crypt cell in single whole body irradiation was 2.8. This RBE value is changed differently in different biologic systems such as mouse jejunal crypt cells, intestine and bone marrow in different irradiation method, so that in fractionated irradiation RBE is variable to the different fraction size and total dose, and also variable to the number of fractions.

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