• Development and Reproduction
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• v.12 no.2
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• pp.117-124
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• 2008

The efficient strategies to cope with unpredictable and/or harmful environmental changes have been developed by every organism in order to ensure its survival and continuity of it's own species. As a results, all living things on earth maintain dynamically internal stability via a process termed 'homeostasis' among physiological parameters despite of external environment changes. Stress is an emotional and physical response to threat homeostasis. Stress may have not only transient but rather permanent effect on the organism; recent evidence clearly show that prenatal stress could organize or imprint permanently physiological systems without any change in genetic codes, a process known as 'epigenetic programming'. In this review, a series of reproduction-associated events occurred in prenatally stressed male rats such as alteration in the structure of sexually dimorphic brain regions, modification of neurotransmitter metabolism, changes in reproductive endocrine status, and finally, disorders of sexual behavior will be introduced. The fetal brain is highly sensitive to prenatal programming and glucocorticoids in particular have powerful brain-programming properties. The chronic hyperactivation of fetal brain by maternal stress-induced glucocorticoid input will provide new program via increasing the neuroplasticities. This 'increased neuroplasticities' will be the basis for the 'increased phenotypic plasticities' rendering the organism's better adaptation to environmental challenges. In conclusion, organism who experienced 'harsh' environment in his fetal life seems to give up a certain portion of reproductive competence to make good chance of survival in his future life by epigenetic (re)programming.

• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.306-315
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• 2019

The estuary of the Han River constantly suffers from pollutants and pathogenic microorganisms which could cause serious damage to aquatic organisms living there. Despite of this potential risk, it is hard to find any reliable scientific reports on the status of reportable disease infection to the organisms living in this area. In this study, cyprinid fish and crustaceans in Jeonryu-ri, a region of the Han River estuary, were investigated for the infection by representative reportable communicable diseases(SVC, spring viraemia of carp; KHVD, koi herpesvirus disease; EUS, epizootic ulcerative syndrome; WSD, white spot disease) and parasites. Peripheral fish and primary freshwater fish were observed in Jeonryu-ri with cyprinid caught most frequently. Crustaceans were mostly marine species. No positive bands to any of the reportable diseases were produced in any of the fish and crustacean examined in this study by PCR. No trace of Clonorchis sinensis, a liver fluke potential threat to human health, was detected in any of fish samples. However, many fish were infected by metacecaria of other flukes, and other various parasites such as nematode, cestode, copepod, monosite and acanthocephalan. These results suggest that important aquatic organisms in the Han River estuary is not seriously polluted yet. However, it is important to keep monitoring the diseases since the water quality in this region is constantly changing, and devastating influence of infectious diseases is unpredictable. Further, it is required to expand monitoring area toward upstream and increase the number of fish for examination.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.227-234
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• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• Journal of Environmental Science International
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• v.25 no.12
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• pp.1633-1641
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• 2016

Leptalina unicolor is a hesperiid butterfly with a restricted distribution in Korea, Japan, China, and Russia. Recently, the number of individuals is rapidly decreased in their natural habitat. This skipper has been classified as an endangered species in the 'Red Data Book', and according to an IUCN report, is under threat of extinction. Therefore, the conservation and restoration of this species both locally and globally are urgently needed. A population of L. unicolor was found in an unknown habitat in Jaeyaksan, Miryang, Gyeongsangnam-do, Korea in 2011, and these individuals were used in the present study. Here, the life cycle, characteristics of each instar larva and breeding information were determined by breeding L. unicolor in the laboratory from 2012 to 2015. The results indicated that L. unicolor occurs twice a year and over-winter as a fifth instar larva. A spring-form female individual laid $17.25{\pm}5.52eggs$, and summer form laid $29.00{\pm}5.86eggs$; it takes $53.79{\pm}0.73days$ for L. unicolor to develop from eggs to adults. After spawning, the eggs developed in $6.16{\pm}0.18days$, and larvae developed in $33.71{\pm}0.58days$; the pre-pupal stage to emergence required $14.22{\pm}0.31days$. Based on these results, we presented effective breeding information for the restoration and proliferation of the species. Several candidate plants species have been reported in the literature as a food source for L. unicolor, but we found that the preferred diet this butterfly was Miscanthus sinensis. The larvae could move easily when their preferred diet was planted in ${\geq}80%$ the cage floor area Year-round breeding was achieved by placing overwintering individuals in low temperatures in autumn. To our knowledge, this is the first study to the biology of L. unicolor in Korea, and the results of this study could be used as preliminary information for the conservation and restoration of this species in its natural habitat.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.173-178
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• 2011

BACKGROUND: Starfish is one of major sea invertebrates that have become a serious economic threat to aquacultural farms in Korea. Much effort has sacrificed to reduce the economic losses of the farms by predatory starfish, including developing and searching biological resources for medicinal and agricultural purposes. In the present study, we investigated aphicidal activity of the extracts from the starfish Asterina pectinifera against green peach aphid. METHODS AND RESULTS: Fresh starfishes were cut into small pieces, homogenized and soaked in methanol. The methanol extracts were centrifuged and the resulting supernatant was subjected to aphicidal activity assays and a series of silica gel column chromatography. More than 70% mortality of aphids were observed by the extracts at a concentration of 1,000 mg/L, exhibiting dose-dependent mortality. TOF-MS analyses detected polyhydroxysteroid as a main aphicidal compound from the starfish extracts. Transmission electronic microscopy could demonstrate that the extracts with polyhydroxysteroid caused aphids death by affecting their epicuticular membrane. CONCLUSION(s): This is the first report of aphicidal activity of the starfish Asterina pectinifera extracts against green peach aphid. Starfish biological resources may be used as a potential candidate for developing a new type natural insecticide.

• Journal of Environmental Policy
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• v.7 no.4
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• pp.75-103
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• 2008

It is widely recognized that destruction of the eco-system with the counter-effect from the rapid industrialization threatens the life of human species. Furthermore, the extinction of some wild species keeps sending a warning message on the threat to human lives in the sense that both the human and wild lives have coexisted for a long time before the industrialization. Therefore, this study will shed a light on the importance of a natural ecology protection, focusing on wild-life conservation. This will provide an opportunity to consider the economic value of biodiversity through conservation of diverse wild lives and a natural ecology. Also, the irreversible damage to natural resources and extinction of certain species represent the urgency of this issue. This paper will perform a theoretical examination on the concept of wild plants and animals, an analysis of factors influencing their survivals, as well as the theory of natural ecology protections. This also examine the problems arising out of current domestic legislation of a natural ecology protection, comparing it with case studies of foreign countries. Through these analysis, this paper will seek for a maintenance of the currently enforcing natural ecology protection law to overcome its limits and will ultimately find alternatives to current system.

• 한국사회정책
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• v.23 no.1
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• pp.203-225
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• 2016

The permanent disability benefit(PDB) system whose purpose lies in helping affected workers with their self-realization through compensating them for their work-related injury or disease and facilitating their timely return to work is very important in terms of social welfare. Actually, the portions of PDB's in all WCI expenditures have been on the sharp increase. In spite of its positive aspects like this, however, an excessive amount of PDB's may have negative impacts on the affected workers' will to work or return to work, and increasing trends in the amount of PDB's payable in annuity will remain in an aging or aged society a potentially risky factor posing a threat to the soundness of WCI budgets. In this respect, the author attempted herein to identify the long-term reality of trends in the number of claimants entitled to PDB's and the amount of PDB's payable to them through making the long-term budget projections of PDB's; address problems with PDB's payable in annuity, which are or will potentially be one of the gravest burdens in securing the soundness of WCI budgets; and discuss how to optimize the amount of PDB's through studying & analyzing overseas cases and income replacement rates and what kinds of improvements are thinkable. It's recommended to reduce the absolute amount of benefits payable in annuity in a phased way considering claimants' life-cycle instead of sticking to the current system, which takes the form of lifelong pension plan.

• Journal of the Institute of Convergence Signal Processing
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• v.16 no.3
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• pp.108-114
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• 2015

Ballast water is carried by ships to ensure stability, trim and structural integrity. When a ship loads cargo, the ballast water is discharged. When foreign marine microorganisms are introduced into new marine environments, they pose a threat to the local marine ecological system. UV system is commonly used for the disinfection of waste and surface water. This method would not be as efficient because some species do survive to form viable populations, much of the sediment and organisms at the bottom of tanks, and may become serious pests. In this paper, we designed and implemented ballast water treatment system using fuzzy PID controller to prevent lamp damage, and to reduce the formation of the viable populations. The experiments were conducted with ballast water treatment system using fuzzy PID controller with short time exposure to the temperature above $40^{\circ}C$. This system was shown to be effective by significantly reducing bacterial population and lamp life extension through appropriate temperature of ballast water.

• Journal of the Korea Society of Computer and Information
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• v.25 no.10
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• pp.69-75
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• 2020

Although various information and communication technologies occupy a place in daily life in the face of the fourth industrial revolution, the contents related to information security in elementary and secondary education courses are mainly related to personal information protection, and the contents and countermeasures of rapidly changing security threats are low in textbooks, and they are far behind the changes. To improve this, this paper suggests that education contents related to information security are included in elementary school real and middle school information textbooks, educational contents related to wireless network and PC security are included to cope with rapidly changing security threats that may arise from the age of the Internet of Things, non-face-to-face classes, and case-based information ethics education can be organized to eradicate curiosity about hacking. Through this paper, we will help prevent information security accidents by establishing basic security measures on our own and strengthening security awareness in the information age.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5823-5828
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• 2012

Background: Breast cancer (BC) is one of the most common cancer affecting women worldwide. Although a great deal of progress has been made in the health sciences, early diagnosis, and increasing community awareness, breast cancer remains a life-threatening illness. In order to reduce this threat, breast cancer screening needs to be implemented in all communities where possible. Objective: The purpose of this study was to examine health beliefs, attitudes and behaviors about breast cancer and breast self-examination of Turkish women. Methods: Data were collected from a sample of 656 women, using an adapted Turkish version of Champion's Health Belief Model Scale (CHBMS), between January and May 2011, in Ordu province of Turkey. Results: The results showed that 67.7% of women had knowledge about and 55.8% performed BSE, however 60.6% of those who indicated they practiced BSE reported they did so at irregular intervals. CHBMS subscales scores of women according to women's age, education level, occupation, family income and education level of the women's mothers, family history of breast cancer, friend and an acquaintance with breast cancer, knowledge about breast cancer, BSE and mammography were significantly different. Conclusion: Knowledge of women about the risks and benefits of early detection of breast cancer positively affect their health beliefs, attitudes, and behaviors. Health care professionals can develop effective breast health programs and can help women to gain good health behavior and to maintain health.