• Journal of Animal Science and Technology
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• v.56 no.7
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• pp.26.1-26.10
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• 2014

Background: Endocrine disruptors are exogenous substance, interfere with the endocrine system, and disrupt hormonal functions. However, the effect of endocrine disruptors in different species has not yet been elucidated. Therefore, we investigated the possible effects of $17{\beta}$-estradiol (E2), progesterone (P4), genistein (GEN) and 4-tert-octylphenol (OP), on capacitation and the acrosome reaction in bovine, mouse, and porcine spermatozoa. In this in vitro trial, spermatozoa were incubated with $0.001-100{\mu}M$ of each chemical either 15 or 30 min and then assessed capacitation status using chlortetracycline staining. Results: E2 significantly increased capacitation and the acrosome reaction after 30 min, while the acrosome reaction after 15 min incubation in mouse spermatozoa. Simultaneously, capacitation and the acrosome reaction were induced after 15 and 30 min incubation in porcine spermatozoa, respectively. Capacitation was increased in porcine spermatozoa after 15 min incubation at the lowest concentration, while the acrosome reaction was increased in mouse spermatozoa after 30 min (P < 0.05). E2 significantly increased the acrosome reaction in porcine spermatozoa, but only at the highest concentration examined (P < 0.05). P4 significantly increased the acrosome reaction in bovine and mouse spermatozoa treated for 15 min (P < 0.05). The same treatment significantly increased capacitation in porcine spermatozoa (P < 0.05). P4 significantly increased capacitation in mouse spermatozoa treated for 30 min (P < 0.05). GEN significantly increased the acrosome reaction in porcine spermatozoa treated for 15 and 30 min and in mouse spermatozoa treated for 30 min (P < 0.05). OP significantly increased the acrosome reaction in mouse spermatozoa after 15 min (P < 0.05). Besides, when spermatozoa were incubated for 30 min, capacitation and the acrosome reaction were higher than 15 min incubation in E2 or GEN. Furthermore, the responsiveness of bovine, mouse and porcine spermatozoa to each chemical differed. Conclusions: In conclusion, all chemicals studied effectively increased capacitation and the acrosome reaction in bovine, mouse, and porcine spermatozoa. Also we found that both E2 and P4 were more potent than environmental estrogens in altering sperm function. Porcine and mouse spermatozoa were more responsive than bovine spermatozoa.

• Nutrition Research and Practice
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• v.2 no.2
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• pp.74-79
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• 2008

Zinc plays a protective role in anti-atherosclerosis but the clear mechanism has not been proposed yet. In the present study, we evaluated whether zinc modulates atherosclerotic markers, VACM-1 and ICAM-1 and cell viability both in endothelial cells in vitro and mouse aortic cell viability ex vivo. In study 1, as in vitro model, endothelial EA.hy926 cells were treated with $TNF{\alpha}$ for 5 hours for inducing oxidative stress, and then treated with Zn-adequacy ($15\;{\mu}M$ Zn) or Zn-deficiency ($0\;{\mu}M$ Zn) for 6 hours. Pro-atherosclerosis factors, VCAM-1 and ICAM-1 mRNA expression and cell viability was measured. In study 2, as ex vivo model, mouse aorta ring was used. Mourse aorta was removed and cut in ring then, cultured in a 96-well plate. Aortic ring was treated with various $TNF{\alpha}$ (0-30 mg/ml) and intracellular zinc chelator, N, N, N', N', -tetrakis (2-pyridylmethyl) ethylenediamine (TPEN, $0-30\;{\mu}M$) for cellular zinc depletion for 2 days and then cell viability was measured. The results showed that in in vitro study, Zn-adequate group induced more VCAM-1 & ICAM-1 mRNA expression than Zn-deficient group during 6-hour zinc treatment post-5 hour TNF-$\alpha$ treatment, unexpectedly. These results might be cautiously interpreted that zinc would biologically induce the early expression of anti-oxidative stress through the increased adhesion molecule expression for reducing atherosclerotic action, particularly under the present 6-hour zinc treatment. In ex vivo, mouse aortic ring cell viability was decreased as TNF-$\alpha$ and TPEN levels increased, which suggests that mouse aortic blood vessel cell viability was decreased, when oxidative stress increases and cellular zinc level decreases. Taken together, it can be suggested that zinc may have a protective role in anti-atherosclerosis by cell viability in endothelial cells and aorta tissue. Further study is needed to clarify how pro-atherosclerosis molecule expression is modulated by zinc.

• Journal of Korean Society of Forest Science
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• v.78 no.4
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• pp.381-395
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• 1989

The main purpose of this research is to provide scientific informations about standard wage and performance tariffs in forest management with special reference to working time for thinning. To identify relationships between net working time and tree characteristics, three geographically different sample plots were established at Yangsan, Bongpyung and Jinan and 460 oaks, 372 Japanese larches, 232 red pine and 240 pitch pine mere selected at each sample plots. The results of statistical analysis using multiple regression are as follows ; 1. Five independent variables of breast height diameter(DBH), mid-diameter(MD) large end diameter(LD), log-length(L), No. of branches(NOB) were stable independent of worker and tree species. 2. Comparing correlation coefficient of five independent variables, the best predictive variables, breast height diameter and No. of branches, were selected. Breast height diameter and No. of branches were identified as the most important independent variables in terms of effect on the dependent variable of the working time. 3. Comparing coefficient of determination (Rp) and residual mean square (MSEp), the best Linear regression equation for each tree species was selected as follower : $WT=a+b1{\times}NOB+b2{\times}DBF$ 4. Proportion of hang-up time to total working time in thinning were 66% in oak stand, 74%, in Japanese larch stand, 55%, in red pine stand and 52% in pitch pine stand, respectively. 5. Based on the best regression equation, a table of working time was made by strata of number of branches and breast height diameter. 6. Total working time using the best regression equation in Table 5 can be predicted in terms of felling time, limbing time, hang-up time, i.e., total working time increases by 11 to 13 seconds with every 1 centimeter increase in breast height diameter from 7 to 16 centimeter.

• Steel and Composite Structures
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• v.49 no.2
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• pp.245-255
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• 2023

The present paper summarizes the results of an experimental program on the influence of using waste lathe scraps in the concrete mixture on the shear behavior of RC beams with different amounts of shear reinforcement. Three different volumetric ratios (1, 2 and %3) for the scraps and three different stirrup spacings (160, 200 and 270 mm) were adopted in the tests. The shear span-to-depth ratios of the beams were 2.67 and the stirrup spacing exceeded the maximum spacing limit in the building codes to unfold the contribution of lathe scraps to the shear resistances of shear-deficient beams, subject to shear-dominated failure (shear-tension). The experiments depicted that the lathe scraps have a pronounced contribution to the shear strength and load-deflection behavior of RC beams with widely-spaced stirrups. Namely, with the addition of 1%, 2% and 3% waste lathe scraps, the load-bearing capacity escalated by 9.1%, 21.8% and 32.8%, respectively, compared to the reference beam. On the other hand, the contribution of the lathe scraps to the load capacity decreases with decreasing stirrup spacing, since the closely-spaced stirrups bear the shear stresses and render the contribution of the scraps to shear resistance insignificant. The load capacity, deformation ductility index (DDI) and modulus of toughness (MOT) values of the beams were shown to increase with the volumetric fraction of scraps if the stirrups are spaced at about two times the beam depth. For the specimens with a stirrup spacing of about the beam depth, the scraps were found to have no considerable contribution to the load capacity and the deformation capacity beyond the ultimate load. In other words, for lathe scrap contents of 1-3%, the DDI values increased by 5-23% and the MOT values by 63.5-165% with respect to the reference beam with a stirrup spacing of 270 mm. The influence of the lathe scraps to the DDI and MOT values were rather limited and even sometimes negative for the stirrup spacing values of 160 and 200 mm.

• Korean Journal of Poultry Science
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• v.36 no.4
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• pp.323-328
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• 2009

In order to determine the origin and genetic diversity among chicken breeds, mitochondrial (mt) DNA D-loop sequences have been widely used. In this study, 41 individuals from four breeds (Korean native chicken (Black and Brown) and two imported breeds, Rhode Island Red and Cornish) were used for identifying genetic relationships with other chicken breeds. We obtained ten haplotypes and the highest number of haplotype was represented by eight individuals each from haplotype 1 and haplotype 2. Neighbor-joining phylogenetic tree indicates that the black and brown Korean native chicken breeds were mixed in haplotype 2 and they were closely related with the red jungle fowl (Gallus gallus). We also investigated whether the D-loop hypervariable region in chicken mtDNA can be used for the breed identification marker. The results indicated that the combination of the SNPs in the D-loop region can be possibly used for the breed discriminating markers. The results obtained in this study can be used for designing proper breeding and conservation strategies for Korean native chicken, as well as development of breed identification markers.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.657-668
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• 1996

To investigate the factors which affecting the cognitive impairment of the 60 or more age group, the authors surveyed for the subjects in some area of Kyungnam Province. 201 studied subjects were tested for cognitive function with mini-mental state examination(MMSE). Information on demographic characteristics and life style has been collected through direct interview. The concentration of Ai and Ca of subject's drinking water, which might be related with cognition, was measured by Inductively Coupled Argon Plasma Spectrometer. The main results were summarized as follows. 1. The prevalence rate of cognitive impairment was 18.4% in male and 45.2% in female and this sexual difference was statistically significant(p=0.03). And the uneducated or illiterated showed significantly high prevalence rate of cognitive impairment(p=0.02). 2. In stratified analysis by sex md education year, we can not see significant trend indicating the neurotoxic effects of aluminum and protective effects of calcium to the cognitive function(p>0.05). 3. The correlation between the concentration of aluminum in drinking water and the MMSE score in whole subjects showed weak negative relationship(r=-0.066). But there was no statistical significance(p=0.434).

• Analytical Science and Technology
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• v.11 no.4
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• pp.297-304
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• 1998

The three analysis methods, EPA method 3050, the method offered by Ministry of Environment in Korea, and modified method corrected in this laboratory, were studied to investigate the effect of matrix on the analysis of inorganic priority pollutants. 7 inorganic priority pollutants(Ni, Cr, Cu, Zn, Pb, Cd, Hg) were spiked to the plating, leather, paper, electric, and dye sludges. Mean recovery of the elements except Hg was 95.5% when the procedure of EPA method was applied. However, recovery by the two other extraction methods showed 11.1% and 27.7%, respectively. Digestions were done by MDS (microwave digestion system) and $HNO_3+HClO_4$ methods. To study organic and inorganic matrix effect, samples were made by adding triethanol amine as a organic matrix and $FeCl_3{\cdot}6H_2O$+$AlCl_3{\cdot}6H_2O$ as a inorganic matrix, respectively. The extracts were analyzed by AAS and HG-AAS. Mean recovery of the elements by the $HNO_3+HClO_4$ procedure, except Hg, gave better result than that of the MDS method. Mean recovery of elements was decreased when organic and inorganic matrices were added in the sludge samples. The procedure of MDS and $HNO_3+HClO_4$ digestion gave higher recoveries than that of direct analysis. In general, the results of the studies showed a significant matrix effect on the inorganic priority pollutants analysis in sludges.

• 한국해양학회지
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• v.30 no.5
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• pp.426-435
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• 1995

In order to assess the significance of ciliate grazing on bacterial population in carbon flow of the estuarine pelagic ecosystem of the Mankyung and Dongjin river (MD estuary), abundance and biomass of ciliates and grazing rate on bacteria of small (<40 um) ciliates were measured. Saplings were carried out four times from October 1993 to March 1995 in the estuarine system. Ciliates smaller than 40 um occupied more than 49.5% of total ciliates abundance. Clearance rate of small ciliates ranged from 18.0 to 16.3 nl cell/SUP -1/ h/SUP -1/. As bacterial abundance increased, ciliate's clearance rate decreased, suggesting that bacterial abundance effects on ciliate's grazing rate. Ciliate grazing rate was equal to 0.1 to 12.2% of bacterial productivity, and the ratio of ciliate ingestion over bacterial production increased exponentially with the increase of bacterial abundance (r$^2$=0.62, p$\leq$0.001). It seems that the effect of ciliate grazing on bacteria would be small in coastal waters and large in more eutrophic waters of high bacterial abundance. Carbon supplied by ciliate grazing on bacteria was avg. 3.1% of carbon amount required for the ciliate maximum productivity. Thus, the ecological role of ciliate in microbial loop was probably more important as a final consumer than as a direct consumer of bacteria.

• Journal of agricultural medicine and community health
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• v.20 no.1
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• pp.51-60
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• 1995

This study was to examine the awareness of health and the utilization of primary health care in rural areas. The data were obtained from self-administered questionnaire conducted 450 parents of Mi Gum md Su Dong middle school students in Nam yang Ju city, Kyung Gi-Do, Korea, from December 15 to 20 in 1993. The results were as follows : 1) Among the causes of disease, 'insufficient health care' was the highest(39.1%), and 'bad environment'(28.9%), 'complexity of life style'(17.8%) in next order. 2) In the priority between 'daily farm work' and 'primary health care', only 45.6% of respondents answered that primary health care is more important than the daily farm work. The 29.8% of respondents answered 'daily farm work', and the 23.1% answered 'the equal of the both'. 3) The 63.6% of the respondents recognized correctly, the meaning of primary health care. And the rate of information source in primary health care were 'TV and Radio'(42.2%), 'medical facilities'(23.3%), and 'newspaper and magazine'(11.3%) in order. 4) In the choice rate of medical facilities for primary health care, 'drug store' was the highest(34.9%), and 'local private clinic'(34.7%), 'health (sub)center'(15.8%), 'hospital'(10.2%) in next order. 5) The 53.5% of the respondents had experienced to visit the health (sub)center more than once. And the disfavorite reasons of health (sub)center were 'insufficient equipment'(36.7%), 'inavailable time to visit'(26.9%), and 'poor treatment'(9.1%). 6) Among the preference of the physicians for primary health care, 'specialist' was the highest rate of the respondents(54.2%), and 'general practitioner'(32.4%), and 'family doctor'(9.8%) in next order. The major obstacles in utilizing the medical facilities for primary health care were 'daily farm work'(41.6%), 'distance'(21.1%) and 'medical cost'(10.4%) in order. 7) The weakened reasons in health (sub)center function were 'insufficient medical equipment'(44.4%), 'the lack of resident's understanding for health (sub)center'(21.8%), and 'short thought of duty in health (sub)center personnel'(16.9%) in order.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4567-4570
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• 2013

Background: Nasopharyngeal carcinoma (NPC) is the commonest radiocurable cancer in Malaysia. This study aimed to determine the treatment outcomes and late effects of radiotherapy for NPC patients treated in University Malaya Medical Centre (UMMC). Materials and Methods: All newly diagnosed patients with NPC referred for treatment to the Oncology unit at UMMC from 2004-2008 were retrospectively analyzed. Treatment outcomes were 5 years overall survival (OS), disease free survival (DFS), cause-specific survival (CSS), locoregional control (LRC) and radiotherapy-related late effects. The Kaplan-Meier method was used for survival analysis and differences in survival according to AJCC stage was compared using the log-rank test. Results: A total of 176 patients with newly diagnosed NPC were treated in UMMC during this period. Late presentation was common, with 33.5% presenting with T3-4 disease, 84.7% with N1-3 disease and 75.6% with AJCC stage 3-4 disease. Radical RT was given to 162 patients with 22.7% having RT alone and 69.3% having CCRT. The stipulated OTT was 7 weeks and 72.2% managed to complete their RT within this time period. Neoadjuvant chemotherapy was given to 14.8% while adjuvant chemotherapy was administered to 16.5%. The 5 years OS was 51.6% with a median follow up of 58 months. The 5 years OS according to stage were 81.8% for stage I, 77.9% for stage II, 47.4% for stage III and 25.9% for stage IV. The 5 years overall CSS, DFS and LRC were 54.4%, 48.4% and 70.6%, respectively. RT related late effects were documented in 80.2%. The commonest was xerostomia (66.7%). Other documented late effects were hearing deficit (17.3%), visual deficit (3.1%), neck stiffness (3.1%), dysphagia (3.4%), cranial nerve palsy (2.5%), pneumonitis (0.6%) and hypothyroidism (1.2%). Conclusions: The 5 years OS and LRC in this study are low compared to the latest studies especially those utilizing IMRT. Implementation of IMRT for NPC treatment should be strongly encouraged.