• Journal of Microbiology
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• 제34권1호
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• pp.54-60
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• 1996

Taking advantage of the heat inducible HSP82 gene in yeast, chromatin structure after transcription cessation was investigated. Alteration of chromating conformation within the HSP82 gene transcription unit into an active state has been shown to correlate with its transcriptional induction. It was thus of interest to examine whether the active chromatin state within the HSP82 mRNA analysis, the gene ceased its transcription within a few hours of cultivation at a normal condition after heat induction. In this condition, an active chromatin conformation in the HSP82 gene body was changed into an inactie state which was revealed by DNase I resistance and by typical nucleosomal cutting periodicity in the corresponding chromatin. These results thus ruled out the possibility of a long-term maintenance of the DNase I sensitive chromatin after transcription cessation. DNA replication may be a critical event for the chromatin reprogramming.

• Journal of Microbiology and Biotechnology
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• 제25권2호
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• pp.145-151
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• 2015

Graphene is a next-generation biomaterial with increasing biomedical applicability. As a new class of one-atom-thick nanosheets, it is a true two-dimensional honeycomb network nanomaterial that attracts interest in various scientific fields and is rapidly becoming the most widely studied carbon-based material. Since its discovery in 2004, its unique optical, mechanical, electronic, thermal, and magnetic properties are the basis of exploration of the potential applicability of graphene. Graphene materials, such as graphene oxide and its reduced form, are studied extensively in the biotechnology arena owing to their multivalent functionalization and efficient surface loading with various biomolecules. This review provides a brief summary of the recent progress in graphene and graphene oxide biological research together with current findings to spark novel applications in biomedicine. Graphene-based applications are progressively developing; hence, the opportunities and challenges of this rapidly growing field are discussed together with the versatility of these multifaceted materials.

• Journal of Yeungnam Medical Science
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• 제24권2호
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• pp.97-106
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• 2007

Functional electrical stimulation (FES) has developed over the last 35 years to become a scientifically, technologically and clinically recognized field of interest in clinical medicine. FES has been applied to locomotion, grasping, ventilation, incontinence, and decubitus healing. However, all of these achievements illustrate the initial applications of FES; its true potential has not yet been realized. Recently, FES systems, which are miniaturized stimulation devices, have been utilized in the clinical setting. However, because the stimulating electrodes of the current FES devices are percutaneous electrodes, which are susceptible to wire breakage, and skin infection an implantable FES stimulating electrode has been introduced in the U.S. and Japan. In the present study, an external power supply method using radio frequency (RF) coupling and data transmission was developed for the control of the implantable FES device. In addition, we review the current understanding of FES devices and their application in clinical medicine.

• Reproductive and Developmental Biology
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• 제35권4호
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• pp.503-510
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• 2011

Cellular uptake of nanoparticles for stem cell labeling and tracking is a critical technique for biomedical therapeutic applications. However, current techniques suffer from low intracellular labeling efficiency and cytotoxic effects, which has led to great interest in the development of a new labeling strategy. Using silica-coated nanoparticles conjugated with rhodamine B isothiocyanate (RITC) (SR), we tested the cellular uptake efficiency, biocompatibility, proliferation or differentiation ability with murine bone marrow derived hematopoietic stem/progenitor cells. The bone marrow hematopoietic cells showed efficient uptake with SR with dose or time dependent manner and also provided a higher uptake on hematopoietic stem/progenitor cells. Biocompatibility tests revealed that the SR had no deleterious effects on cell cytotoxicity, proliferation, or multi-differentiation capacities in vitro and in vivo. SR nanoparticles are advantageous over traditional labeling techniques as they possess a high level of cellular internalization without limiting the biofunctionality of the cells. Therefore, SR provides a useful alternative for gene or drug delivery into hematopoietic stem/progenitor cells for basic research and clinical applications.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제14권4호
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• pp.322-331
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• 2014

Chaotic dynamics is an active area of research in biology, physics, sociology, psychology, physiology, and engineering. This interest in chaos is also expanding to the social scientific fields such as politics, economics, and argument of prediction of societal events. In this paper, we propose a dynamic model for addiction of tobacco. A proposed dynamical model originates from the dynamics of tobacco use, recovery, and relapse. In order to make an addiction model of tobacco, we try to modify and rescale the existing tobacco and Lorenz models. Using these models, we can derive a new tobacco addiction model. Finally, we obtain periodic motion, quasi-periodic motion, quasi-chaotic motion, and chaotic motion from the addiction model of tobacco that we established. We say that periodic motion and quasi-periodic motion are related to the pre-addiction or recovery stage, respectively. Quasi-chaotic and chaotic motion are related to the addiction stage and relapse stage, respectively.

• Entomological Research
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• 제48권6호
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• pp.480-489
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• 2018

Due to the increasing interest in natural biopolymers including chitin, the exploitation of economic and easily accessible chitin sources with good physicochemical properties is nowadays required. In view of this fact, in the current study chitin was extracted and physicochemically characterized from six Cicadas (Hemiptera: Homoptera: Cicadoidea) species collected from Mediterranean region of Turkey (2014-15). Chitin was extracted using a classic extraction method that includes acid and base treatment. TGA results revealed a remarkable increase ($410-412^{\circ}C$) for all the six Cicada species compared to other chitin samples extracted from various sources. For all of the six selected species the chitin contents on the dry basis were determined as 6.7% for Cicadatra atra, 5.51% for C. hyalina, 8.84% for C. platyptera, 4.97% for Cicada lodosi, 6.49% for C. mordoganensis, and 5.88% for Cicadetta tibialis. The surface morphology of chitin isolates from Cicada species was observed to consist of nanofibers and nanopores.

• 한국과학교육학회지
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• 제12권3호
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• pp.119-128
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• 1992

The contents of two elementary science textbooks are analyzed; they are HBJ Science and Holt Science. A) The ratio of the contents is as follows physics area, 21-27% ; chemistry area, 6-7% ; biology area, 32-41% ; earth science area, '27-31 %. B) The jobs related in science and technology are introudced in both textbooks. The kinds of jobs found in Holt Science and HBJ Science are 94 and 55, respectively. C) There cent developments in science and technology are introduced in Holt Science and HBJ Science are 57 and 46 times respectively. The introductoin of the recent development of science & technology and the jobs relcated in science & technology may interest children in science.

• Molecules and Cells
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• 제25권2호
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• pp.149-157
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• 2008

Dopamine is a major neurotransmitter in the mammalian central nervous system (CNS) that regulates neuroendocrine functions, locomotor activity, cognition and emotion. The dopamine system has been extensively studied because dysfunction of this system is linked to various pathological conditions including Parkinson's disease, schizophrenia, Tourette's syndrome, and drug addiction. Accordingly, intense efforts to delineate the full complement of signaling pathways mediated by individual receptor subtypes have been pursued. Dopamine D1-like receptors are of particular interest because they are the most abundant dopamine receptors in CNS. Recent work suggests that dopamine signaling could be regulated via dopamine receptor interacting proteins (DRIPs). Unraveling these DRIPs involved in the dopamine system may provide a better understanding of the mechanisms underlying CNS disorders related to dopamine system dysfunction and may help identify novel therapeutic targets.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제13권4호
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• pp.291-297
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• 2013

Chaotic dynamics have been studied by many researchers in the fields of biology, physics, and engineering. Interest in chaos is also expanding to the social sciences such as politics, economics, and others, including the prediction of societal events. The concept of leisure has developed from a passive concept correlated with relaxation, entertainment, and ideology formation into a positive concept that assumes a more active role. As information and communications technology develops, digital leisure activity is expected to continue spreading. This expansion of digital leisure function correctly, as well as. Traditional leisure activity functions correctly more, whereas digital leisure activity is predicted to function incorrectly more often. In this paper, we propose a mathematical addiction model of digital leisure that deals with its dysfunctions such as addiction to digital leisure, including computer games, internet search, internet chatting, and social media. Herein, to solve addiction to digital leisure, we propose a model derived from a nicotine addiction.

• 한국동물학회지
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• 제15권1호
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• pp.15-21
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• 1972

두 케이스의 자궁암 조직을 배양하여 그들의 염색체를 구룹별로 분석한 결과는 아래와 같다. 1. 종족세포의 염색체수가 한 경우는 46이었고, 다른 한 환자에서는 60으로서 저3배성을 나타내었다. 2. 후자의 핵형을 구룹별로 분석한 결과, 구룹간의 염색체 분포는 non-random인 것으로 나타났다.