• Computers and Concrete
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• v.23 no.6
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• pp.421-431
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• 2019

The alarming rate of depletion of natural stone based coarse aggregates is a cause of great concern. The coarse aggregates occupy nearly 60-70% by volume of concrete being produced. Research efforts are on to look for alternatives to stone based coarse aggregates from sustainability point of view. Response surface methodology (RSM) is adopted to study and address the effect of ferrochrome slag (FCS) replacement to coarse aggregate replacement in the ordinary Portland cement (OPC) based concretes. RSM involves three different factors (ground granulated blast furnace slag (GGBS) as binder, flyash (FA) as binder, and FCS as coarse aggregate), with three different levels (GGBS (0, 15, and 30%), FA (0, 15, and 30%) and FCS (0, 50, and 100%)). Experiments were carried out to measure the responses like, workability, density, and compressive strength of FCS based concretes. In order to optimize FCS replacement in the OPC based concretes, three different traditional optimization techniques were used (grey relational analysis (GRA), technique for order of preference by similarity (TOPSIS), and desirability function approach (DFA)). Traditional optimization techniques were accompanied with principal component analysis (PCA) to calculate the weightage of responses measured to arrive at the final ranking of replacement levels of GGBS, FA, and FCS in OPC based concretes. Hybrid combination of PCA-TOPSIS technique is found to be significant when compared to other techniques used. 30% GGBS and 50% FCS replacement in OPC based concrete was arrived at, to be optimal.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.58-68
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• 2021

Several herbs including Artemisia are known to possess conceptive property. In the present study, mouse spermatozoa were incubated with ethanol extract of Artemisia vulgaris leaves. The effect of extract on acrosome exocytosis was studied by labeling spermatozoa with fluorescein isothiocyanate (FITC) peanut agglutinin and by staining with Coomassie blue. Viability and membrane integrity were studied by Trypan-blue staining and hypo-osmotic swelling test. Artemisia extract at very low concentration caused precocious acrosome reaction and loss of sperm viability. Acrosome reaction increased remarkably from 22.63% to 88.42% with increasing extract concentration from 0 to 2,000 ㎍/mL. However, the viability loss of spermatozoa was increased from 11.71% in control to 63.73% in samples treated, evaluated by Trypan-blue staining method. Membrane damage caused by the extract, evaluated by hypo-osmotic swelling test was even low, ranging from 2.27% to only 24.23%. These results indicate that Artemisia extract might block fertilization by causing precocious acrosome exocytosis in spermatozoa. A direct contraceptive effect was tested by injecting the plant extract into the vagina of female mice and then allowing them to mate with normal males. The treated female mice delivered significantly fewer litters in comparison to the control.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.3
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• pp.129-138
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• 2022

Reintroduction programs have been promoted across the world to recover and rehabilitate endangered birds through ex situ captive breeding and releasing to the nature. The ultimate aims of these reintroduction programs are recovery of sustainable populations in natural habitats. To ensure the success of the reintroduction programs, it is necessary to examine the followings in order to increase the success rate of releasing along with the development of captive breeding techniques: 1) Adequate habitat provision, 2) adaptability of captive-bred individuals, 3) survivability of released individuals, and 4) social interest and will. Before releasing captive-bred individuals, it should be reviewed whether there are habitats in which the limiting factor is removed, and assessed their long-term safety. The quantity and quality of the released individuals must be considered to increase the chances for mate selection, maintain genetic diversity, and acquire the ability to adapt to the wild. The release method must be decided in consideration of characteristics of the target habitats and individuals, and rational means such as careful observation, evaluation, and feedback must be provided throughout the release process. For the long-term success of recovery projects, social awareness, sustainable support, and related experts are needed. Satisfying these criteria can help to increase the success rates of reintroduction programs. For the bird reintroduction program in the future, the feasibility of the methods and procedures must be closely reviewed before starting.

• Journal of Digestive Cancer Research
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• v.10 no.1
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• pp.22-30
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• 2022

Immune checkpoint inhibition has been established as a new treatment option for various types of carcinoma, and many clinical trials are being actively conducted as a treatment for advanced or metastatic gastric cancer, either as a monotherapy with an immune checkpoint inhibitor or as a combination therapy with standard chemotherapy. In the CheckMate-649 clinical trial to confirm the efficacy of the combination of nivolumab and chemotherapy (FP) in advanced gastric cancer and gastroesophageal junction cancer, nivolumab group showed improvement in overall survival in programmed death ligand 1-positive cancer patients compared with placebo group. Also, the combination therapy of pembrolizumab, trastuzumab and chemotherapy (FP) in first-line treatment was tested through the KEYNOTE-811 trial. The pembrolizumab group showed 22.7% of improvement in objective response rate compared with placebo group. Accordingly, the combination of nivolumab/pembrolizumab with standard chemotherapy was approved for the first-line treatment. In KEYNOTE-059 trials for patients with progressive disease after at least two lines of chemotherapy, pembrolizumab monotherapy showed improvement in objective response rate and overall survival, and the use of pembrolizumab was approved for the third-line or more treatment. In this article, we review the result of clinical trials related to immune checkpoint inhibitors that have been recently introduced in the treatment of gastric cancer.

• Toxicological Research
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• v.14 no.2
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• pp.193-203
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• 1998

The toxicity of DA-125. a new anthracycline anticancer agent, on the male reproductive system was studied in Sprague-Dawley rats. Forty male rats were rando$m\ell$y assigned to Jour groups with ten rats in each group and given single intraveneous doses of DA-125 at dose levels of 0. 12.5. 25. and 50 mg/kg body weight. On day 56 after treatment the animals were allowed to mate. and their male reproductive Junctions and organs were examined in detail. Copulated females were sacrificed on day 20 of gestation for examination of embryo-fetal development. One out of ten rats in the 50 mg/kg group died on day 12 after treatment. Clinical signs such as emaciation. sedation, anorexia. swelling. dark material around eye. alopecia. and diarrhea were observed in the 25 and/or 50 mg/kg groups. Reduction in the body weight gain. decrease in the absolute weights of testes. epididymis and seminal vesicles. and/or decrease in the number of testicular sperm heads were also found. Although histopathological changes such as atrophy of seminiferous tubules. loss or decrease of spermatogenic cells. exfoliation of spermatogenic cells. vacuolization of Sertoli cells. decrease of sperm. and/or increase of necrotic spermatogenic cells in epididymal ducts were observed. no adverse effects on the motility and morphology of epididymal sperm. copulation index. fertility index. and embryo-fetal development were detected in the 25 and 50 mg/kg groups. There were no evidences of male reproductive toxicity in the 12.5 mg/kg group. These results show that single intravenouse doses of DA-125 produce significant dose-related testicular atrophy. histopathological changes. and oligozoospermia in rats and $LD_{10}$ for DA-125 appears to be 50 mg/kg body weight.

• Journal of Navigation and Port Research
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• v.37 no.1
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• pp.15-21
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• 2013

This paper investigates the mandatory minimum requirements for certification of officers in charge of a navigational watch on ship specified in the international convention of STCW. The training education and evaluation systems for navigational competence of Korean navy were compared and analyzed. The paper suggests adjustment of the evaluation range, increment of evaluation items, diversification of evaluation types, differentiation of certification-related education by officer's commissioning program in order to improve the PQS system.

• Journal of the Korean Home Economics Association
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• v.43 no.4 s.206
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• pp.173-185
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• 2005

The purposes of this study were to determine the general trends of the family value orientations FVO of overseas Korean women, to investigate differences in related variables, and to examine the relationships between FVO and the related variables. The subjects were 1,413 Korean women over 20 years living abroad in America (363 women), China (555), and Russia Central Asia (495 women). The subjects completed a questionnaire on FVO. Data were analyzed using SPSS. The major findings were as follows: 1. Korean-American women's FVO were modernistic, Korean chinese women's were traditional, and Korean women in Russia Central Asia showed neither traditional nor modem FVO. 2. The overseas Korean women's values were different from the value's dimension. 'Filial piety' showed very traditional value orientations, but 'preference of son , and 'mate selection 'showed modem FVO. The dimensions of FVO were different according to the living region. 3. The FVO values were different according to age, and period of education. Korean-American women's FVO were positively related to age, health condition, and the cognition of being Korean. Korean-Chinese women's FVO were related to age, living condition, marital and parent-child relationship, self-respect, and life satisfaction. Russia Central Asia women's FVO were correlated with age, period of education, living condition, health condition, the cognition of being Korean, marital and parent-child relationship, self-respect, and depression.

• The Korean Journal of Pharmacology
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• v.9 no.1
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• pp.23-37
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• 1973

This paper presents the effect of chronic administration of psychotropic drugs on rats. The experimental animals were litter mates (average initial body weight $47{\pm}1.1g$) whose mother were bred at our laboratory. Each litter mate was treated as one group. Control animals were treated with tap water and each experimental group was treated with caffeine citrate 0.1%, nialamide 0.1%, ethyl alcohol 2.5%, phenobarbital sod. 0.1%, diphenylhydantoin 0.1%, chlorpromazine 0.1%, reserpine 0.005%, diazepam 0.01%, chlorpheniramine 0.01% solutions respectively in drinking water over a period of ten weeks. All rats were allowed food and drinking water ad libitum. The mortality rate and the per cent increase of body weight were recorded weekly throughout the course of the experiment. The effects of above agents on the pentobarbital sleeping time, gastric secretion, and brain and liver weights were studied at the end of ten weeks treatment. The obtained results are summarized as follows: 1. Mortality rate was highest in the groups treated with phenobarbital and chlorpromazine respectively. Through the experimental period (ten weeks), the mortality rate was higher in earlier stage than in the later period. 2. During the period of prolonged administration of psychotropic drugs, only diazepam treated group showed remarkable difference in per cent increase of body weight from the control group of rats. 3. Acute treatment with psychotropic drugs delayed the onset of pentobarbital sleeping time. In contrast, the sleeping time was significantly shortened (p<0.001) when the rats were treated chronically with those agents. 4. The effects of chronic treatment with phenobarbital or diphenylhydantoin on the gastric secretion are as follows: the total acidity was remarkably decreased while the pH was increased. 5. The brain weight was significantly decreased in the ethyl alchol and in the chlorpheniramine treated groups, in the mean time, there was no change in liver weight treated with any psychotropic drugs.

• The korean journal of orthodontics
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• v.3 no.1
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• pp.14-20
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• 1972

It is well known fact that physical growth and development of children are influenced by many factors. The importance of socio-economic, geographic and cultural background cannot be over-emphasized in the evaluation of general pattern of physical growth and development of children. In this study the author measured and studied the body height and body weight of children living in the region of mine and industry located in Young-Wol Kun, Kang-Won Do, for the purpose of exploring out the influence of socio-geographic factors to act on physical growth and development of children. Total number of samples were 4,147 comprising 2,170 in male and 1,977 in female with ages ranging from 7 to 15. 1) The growth curves showed that young males grow slowly by 14 years of age, here-after rapidly and the young females grow slowly by 12 years of age, rapidly by 13 years of age and slowly thereafter. 2) The annual increment curves of body height and body weight showed that the most increment of female occurs by 13 years of age and that of mate, by 15 years of age. 3) The growth curves of the male and female crossed twice. It shows the difference of the pattern of growth between the both sexes. 4) The standards for the children in this region were presented. 5) The time of changes of stndard deviation curves of body height and body wegiht coincided nearly with that of annual increment. 6) Body weight and body height .of the children is larger than that of Korean children before World War II, but smaller than that of standards of recent Korean.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.3
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• pp.453-466
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• 1995

The use of tissue conditioners has come into favor for preprosthetic treatment and the treatment of Denture stomatitis, but the major problem in the use of the tissue conditioner is the growth of C.albicans. To compare the growth of C.albicans according to the type and the wearing period of the tissue conditioner, three commercial tissue conditioners were relined to intraoral plates which were delivered to 14 smoking, 12 nonsmoking healthy men. Cultures were made from the conditioner surface at 2, 7, 14, 21 days after after intraoral placement. The frequency of positive culture and colony counts of C.albicans were measured by imprint culture technique. The following results were achieved : 1. The frequency of positive cluture had increased significantly for all materials used. 2. The frequency of positive culture had incresed significantly around 2,14 days for day for COE-Comfort, SR-Ivoseal. 3. There were no significant difference in the colony counts of C.albicans among the mate rials used. 4. There were an over-all increase with the wearing period of tissue conditioners and significant increase around 2, 7, 14 days for COE-Comfort, and 2, 14 days for SR-Ivoseal, viscogel in colony counts. 5. Smoking had no effect on the growth of C.albicans. That is, there were no difference among the materials used in the growth of C.albicans. In the clinical application of tissue conditioners, we should avoid a long term use of it, but in inevitable cases, special disinfection procedures should be considered.