• Title/Summary/Keyword: Physiological models

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On the Forming Processes of Soil Humic Substances and its Physiological Effects on Plants (토양(土壤) 부식물(腐植物)의 생성(生成)과 효과(効果)에 대(對)한 고찰(考察))

  • Lim, Sun-Uk
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.1
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    • pp.67-73
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    • 1973
  • Soil humic substances are defined as a humified part of the soil organic matters and regarded to play beneficial roles for colloid chemical properties and the fertility of the soils. This paper is referred to review the present trend of the studies on the forming processes of humic substances and on the effect on plant metabolism by some organic compounds that are directly absorbed by plants. It is generally considered that the humic substances are formed organic matters in soil or plant materials through numerous organic or biochemical processes. However, the nature of the constituting "core" and of attachment of carbohydrate, nitrogen containing compounds like protein, phenolic compounds and metals to the core are unclear though various models are suggested. It is reviewed that some organic compounds, phenclic acids, derived from humic substances are effective on plant metablism in many cases, although the mechanisms are remained to be clarified.

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Biological Functions of Organosulfur Compounds in Allium Vegetables (Allium속 식물 유래 함유황 유기화합물의 생리적 유용성)

  • 전향숙;김현정
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.6
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    • pp.1412-1423
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    • 1999
  • This review contains a discussion of the physiological activity of the components of Allium vegetables. Organosulfur compounds in Allium vegetables, such as ajoene, diallyl sulfides and S allylcysteine, have cancer preventive activity in chemically induced animal cancer models. They also have inhibitory effects on proliferation of cancer cells in vitro. Allium vegetables have lipid and cholesterol lowering effect, and platelet aggregation inhibitory activity that help the prevention of cardiovascular diseases. Sulfur con taining compounds, especially allicin and ajoene, have antimicrobial activities against gram negative, positive bacteria and fungi. Moreover, Allium organosulfur compounds such as S allylcysteine showed reducing effects on the senescence related symptoms including cognition. Allium organosulfur compounds have significant importance in food industry as both biologically active ingredients and savory.

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Toxicological Mechanism of Endocrine Disrupting Chemicals: Is Estrogen Receptor Involved?

  • Jeung, Eui-Bae;Choi, Kyung-Chul
    • Toxicological Research
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    • v.26 no.4
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    • pp.237-243
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    • 2010
  • Endocrine disrupting chemicals (EDCs) have been shown to interfere with physiological systems, i.e., adversely affecting hormone balance (endocrine system), or disrupting normal function, in the female and male reproductive organs. Although endocrine disruption is a global concern for human health, its impact and significance and the screening strategy for detecting these synthetic or man-made chemicals are not clearly understood in female and male reproductive functions. Thus, in this review, we summarize the interference of environmental EDCs on reproductive development and function, and toxicological mechanism(s) of EDCs in in vitro and in vivo models of male and female reproductive system. In addition, this review highlights the effect of exposure to multiple EDCs on reproductive functions, and brings attention to their toxicological mechanism(s) through estrogen receptors.

The Design and Implementation of a Driver's Emotion Estimation based Application/Service Framework for Connected Cars (커넥티드 카를 위한 운전자 감성추론 기반의 차량 제어 및 애플리케이션/서비스 프레임워크)

  • Kook, Joongjin
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.67 no.2
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    • pp.100-105
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    • 2018
  • In this paper, we determined the driver's stress and fatigue level through physiological signals of a driver in the connected car environment, accordingly designing and implementing the architecture of the connected cars' platforms needed to provide services to make the driving environments comfortable and reduce the driver's fatigue level. It includes a gateway between AVN and ECU for the vehicle control, a framework for native applications and web applications based on AVN, and a sensing device and an emotion estimation engine for application services. This paper will provide the element technologies for the connected car-based convergence services and their implementation methods, and reference models for the service design.

Neuropeptidomics: Mass Spectrometry-Based Identification and Quantitation of Neuropeptides

  • Lee, Ji Eun
    • Genomics & Informatics
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    • v.14 no.1
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    • pp.12-19
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    • 2016
  • Neuropeptides produced from prohormones by selective action of endopeptidases are vital signaling molecules, playing a critical role in a variety of physiological processes, such as addiction, depression, pain, and circadian rhythms. Neuropeptides bind to post-synaptic receptors and elicit cellular effects like classical neurotransmitters. While each neuropeptide could have its own biological function, mass spectrometry (MS) allows for the identification of the precise molecular forms of each peptide without a priori knowledge of the peptide identity and for the quantitation of neuropeptides in different conditions of the samples. MS-based neuropeptidomics approaches have been applied to various animal models and conditions to characterize and quantify novel neuropeptides, as well as known neuropeptides, advancing our understanding of nervous system function over the past decade. Here, we will present an overview of neuropeptides and MS-based neuropeptidomic strategies for the identification and quantitation of neuropeptides.

Recent Advances in the Nutrition of the High Producing Sow -Review-

  • Easter, R.A.;Kim, S.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.6
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    • pp.769-773
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    • 1998
  • Genetic advances, changes in housing systems and new management strategies have made it necessary to thoroughly review conventional nutritional programs. The approach has changed from one of feeding to permit gradual depletion of fat and protein tissues to one of feeding to maintain long-term nutritional balance. Increasingly the sow is viewed as a dynamic system that can be described by a mathematical model. There is opportunity to improve the initial models through research to provide a better understanding of metabolism and key physiological events in the sow's reproductive life. Direct experimentation remains a very important tool for defining nutritional requirements. Recent data supports increases in amino acid recommendations during lactation. Voluntary feed intake remains an intractable problem during lactation.

Investigation on Airflows in Abnormal Nasal Cavity with Adenoid Vegetation by Particle Image Velocimetry

  • Kim, Sung Kyun;Son, Young Rak
    • Journal of Mechanical Science and Technology
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    • v.18 no.10
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    • pp.1799-1808
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    • 2004
  • Knowledge of airflow characteristics in nasal cavity is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. Since the final goal of these works is their contribution to the diagnosisand treatment of nasal diseases, the next step on this topic is naturally studies for disordered nasal cavities. In this paper, as the first application, airflows in the normal and abnormal nasal cavities with adenoid vegetation are investigated experimentally by PIV, and comparisons of both cases are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticatedcavity model. The CBC PIV algorithm with window offset is used for PIV flow analysis. Average and RMS distributions are obtained for inspirational and expirational nasal airflows. Airflow characteristics that are related with the abnormalities in nasal cavity are presented.

Spot the difference: Solving the puzzle of hidden pictures in the lizard genome for identification of regeneration factors

  • Chung, Jin Woong
    • BMB Reports
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    • v.49 no.5
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    • pp.249-254
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    • 2016
  • All living things share some common life processes, such as growth and reproduction, and have the ability to respond to their environment. However, each type of organism has its own specialized way of managing biological events. Genetic sequences determine phenotypic and physiological traits. Based on genetic information, comparative genomics has been used to delineate the differences and similarities between various genomes, and significant progress has been made in understanding regenerative biology by comparing the genomes of a variety of lower animal models of regeneration, such as planaria, zebra fish, and newts. However, the genome of lizards has been relatively ignored until recently, even though lizards have been studied as an excellent amniote model of tissue regeneration. Very recently, whole genome sequences of lizards have been uncovered, and several attempts have been made to find regeneration factors based on genetic information. In this article, recent advances in comparative analysis of the lizard genome are introduced, and their biological implications and putative applications for regenerative medicine and stem cell biology are discussed.

MicroSPECT and MicroPET Imaging of Small Animals for Drug Development

  • Jang, Beom-Su
    • Toxicological Research
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    • v.29 no.1
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    • pp.1-6
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    • 2013
  • The process of drug discovery and development requires substantial resources and time. The drug industry has tried to reduce costs by conducting appropriate animal studies together with molecular biological and genetic analyses. Basic science research has been limited to in vitro studies of cellular processes and ex vivo tissue examination using suitable animal models of disease. However, in the past two decades new technologies have been developed that permit the imaging of live animals using radiotracer emission, X-rays, magnetic resonance signals, fluorescence, and bioluminescence. The main objective of this review is to provide an overview of small animal molecular imaging, with a focus on nuclear imaging (single photon emission computed tomography and positron emission tomography). These technologies permit visualization of toxicodynamics as well as toxicity to specific organs by directly monitoring drug accumulation and assessing physiological and/or molecular alterations. Nuclear imaging technology has great potential for improving the efficiency of the drug development process.

Shear Stress and Atherosclerosis

  • Heo, Kyung-Sun;Fujiwara, Keigi;Abe, Jun-Ichi
    • Molecules and Cells
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    • v.37 no.6
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    • pp.435-440
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    • 2014
  • Hemodynamic shear stress, the frictional force acting on vascular endothelial cells, is crucial for endothelial homeostasis under normal physiological conditions. When discussing blood flow effects on various forms of endothelial (dys)function, one considers two flow patterns: steady laminar flow and disturbed flow because endothelial cells respond differently to these flow types both in vivo and in vitro. Laminar flow which exerts steady laminar shear stress is atheroprotective while disturbed flow creates an atheroprone environment. Emerging evidence has provided new insights into the cellular mechanisms of flowdependent regulation of vascular function that leads to cardiovascular events such as atherosclerosis, atherothrombosis, and myocardial infarction. In order to study effects of shear stress and different types of flow, various models have been used. In this review, we will summarize our current views on how disturbed flow-mediated signaling pathways are involved in the development of atherosclerosis.