• Journal of the Korean Chemical Society
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• 제8권4호
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• pp.192-199
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• 1964

Seasonal variations of the contents of some chemical constituents of the estuary water at two definite stations of the laver bed in Nack Dong River have been determined over one tidal cycle in spring tide from Nov. 1962 to Oct. 1963. The ranges of annual variations of the contents at station 1 and station 2 are as follows: water temp. $2.2-30.8^{\circ}C$, $3.3-28.0^{\circ}C$; pH 7.8-8.5, 7.9-8.4; chlorosity 0.025-19.66 g/l, 4.31-19.56 g/l; magnesium 0.00355-1.565 g/l, -1.524 g/l; calcium 0.00557-0.482 g/l, - -0.590 g/l; saturation % of dissolved oxygen 71.8-123.2%, 88.2-113.8%; silicate-Si 8.00-125.5 ${\mu}$g-at./l, 6.70-100.5 ${\mu}$g-at./l; phosphate-P 0.12-1.47 ${\mu}$g-at./l, 0.11-1.09 ${\mu}$g-at./l; ammonia-N 4.88-25.45 ${\mu}$g-at./l, 4.12-17.58 ${\mu}$g-at./l; nitrite-N 0.07-0.75 ${\mu}$g-at./l, 0.08-0.58 ${\mu}$g-at./l; nitrate-N 2.11-6.89 ${\mu}$g-at./l, 1.85-7.43 ${\mu}$g-at./l each. The annual tidal variations of the constituents at station 1 are more remarkable than of station 2. The chlorosity, magnesium and calcium contents are decreased nearing the slack after ebb, and increased abruptly then one hour after the slack. The contents of the other constituents are varied according to the chlorosity variety. The values of pH, chlorosity, magnesium and calcium contents are lower in summer than winter, while the difference of seasonal variations of the % saturation of dissolved oxygen is not remarkable. The phosphate-P and total nitrogen contents have a tendency of increasing within a definite range, while the silicate-Si increase proportionally, to the increasing of mixing percentage of fresh water. The average values of Si/P and N/P are several times greater than of the normal in sea water. The chemical composition considered from the value of Mg/Cl or Ca/Cl of estuarine water varies according to the variety of chlorosity, even at the high chlorosity of 19 g/l.

• Korean Journal of Veterinary Research
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• 제40권2호
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• pp.361-371
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• 2000

It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

• Radiation Oncology Journal
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• 제18권4호
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• pp.244-250
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• 2000

Purpose : To see the relationship between the response to chemotherapy and the final outcome of neoadiuvant chemotherapy and radiotherapy in patients with mocanry advanced hypopharyngeal cancer. Methods and Materials :A retrospective analysis was done for thirty-two patients with locally advanced hypopharyngeal cancer treated in the Seoul National University Hospital with neoadiuvant chemotherapy and radiotherapy from August 1979 to July 1997. The patients were treated with Co-60 teletherapy unit or 4MV or 6MV photon beam produced by linear accelerator. Daily fractionation was 1.75 to 2 Gy, delivered five times a week. Total dose ranged from 60.8 Gy to 73.8 Gy. Twenty-nine patients received continuous infusion of cisplatin and 5-FU. Other patients were treated with cisplatin combined with bleomycin or vinblastin. Twenty-four (75$\%$) patients received all three prescribed cycles of chemotherapy delivered three weeks apart. Six patients received two cycles, and two patients received only one cycle. Results :The overall 2-year and 5-year survival rates are 65.6$\%$ and 43.0$\%$, respectively. 5-year local control rate is 34$\%$. Organ preservation for more than five years is achieved in 12 patients (38$\%$). After neoadjuvant chemotherapy, 24 patients achieved more than partial remission (PR): the response rate was 75$\%$ (24/32). Five patients had complete remission (CR), 19 patients PR, and 8 patients no response (NR). Among the 19 patients who had PR to chemotherapy, 8 patients achieved CR after radiotherapy. Among the 8 non-responders to chemotherapy, 2 patients achieved CR, and 6 patients achieved PR after radiotherapy. There was no non-responder after radiotherapy. The overall survival rates were 60$\%$ for CR to chemotherapy group, 35.1$\%$ for PR to chemotherapy group, and 50$\%$ for NR to chemotherapy group, respectively (p=0.93). There were significant difference in five-year overall survival rates between the patients with CR and PR after neoadjuvant chemotherapy and radiotherapy (73.3$\%$ vs. 14.7$\%$, p<0.01). The prognostic factor affecting overall survival was the response to overall treatment (CR vs. PR, p<0.01). Conclusion :In this study, there were only five patients who achieved CR after neoadiuvant chemotherapy. Therefore the difference of overall survival rates between CR and PR to chemotherapy group was not statistically significant. Only the response to chemo-radiotherapy was the most important prognostic factor. There needs to be more effort to improve CR rate of neoadjuvant chemotherapy and consideration for future use of concurrent chemoradiotherapy.

• Korean Journal of Agricultural and Forest Meteorology
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• 제9권2호
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• pp.149-160
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• 2007

KoFlux Gwangneung Supersite comprises complex topography and diverse vegetation types (and structures), which necessitate complementary multi-disciplinary measurements to understand energy and matter exchange. Here, we report the results of this ongoing research with special focuses on carbon/water budgets in Gwangneung forest, implications of inter-dependency between water and carbon cycles, and the importance of hydrology in carbon cycling under monsoon climate. Comprehensive biometric and chamber measurements indicated the mean annual net ecosystem productivity (NEP) of this forest to be ${\sim}2.6\;t\;C\;ha^{-1}y^{-1}$. In conjunction with the tower flux measurement, the preliminary carbon budget suggests the Gwangneung forest to be an important sink for atmospheric $CO_2$. The catchment scale water budget indicated that $30\sim40%$ of annual precipitation was apportioned to evapotranspiration (ET). The growing season average of the water use efficiency (WUE), determined from leaf carbon isotope ratios of representative tree species, was about $12{\mu}mol\;CO_2/mmol\;H_2O$ with noticeable seasonal variations. Such information on ET and WUE can be used to constrain the catchment scale carbon uptake. Inter-annual variations in tree ring growth and soil respiration rates correlated with the magnitude and the pattern of precipitation during the growing season, which requires further investigation of the effect of a monsoon climate on the catchment carbon cycle. Additionally, we examine whether structural and functional units exist in this catchment by characterizing the spatial heterogeneity of the study site, which will provide the linkage between different spatial and temporal scale measurements.

• Journal of the Korean Society of Food Science and Nutrition
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• 제34권3호
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• pp.366-373
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• 2005

This study was carried out to investigate the self-reported health and eating habit of the elite female adolescent athletes in Incheon. The subjects were 102 elite female athletes of middle and high schools located in Inchon. A self-administered Questionnaire was used for this cross-sectional survey. Statistical analysis by two-way ANOVA was performed to discriminate between the main effects of age (as middle and high school athletes) and sports type, and their interaction. As use of nutritional supplements, 35.8% of the total subjects took vitamin and iron supplements and 62.5% of field and track athletes took vitamin and iron supplements. While mental stress related to exercise was much in fencing ＆gt; shooting ＆gt; field and track ＆gt; swimming athletes, physical burden during training was higher in swimming ＆gt; field and track ＆gt; fencing ＆gt; shooting athletes. More than half of the subjects showed irregular menstrual cycle. As the most severe problem of eating habit, they reported skipping meal ＆gt; overeating ＆gt; prejudiced meal ＆gt; preference to salty and spicy foods. More than half of the subjects skipped meal over three times per week. Fencing and shooting athletes showed very significantly higher frequency of skipping meal and more irregular breakfast time compared to those of other sport types. As for snack, they ate cookies, carbonated drink, chocolate, candy ＆gt; milk, yogurt, ice cream ＆gt; cake, bread, rice cake ＆gt; fried noodle ＆gt; hamburger, pizza. Therefore, nutritional counseling and education by sport type are necessary for health and good eating habit of these elite female adolescent athletes.

• Journal of Korean Society of Forest Science
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• 제86권4호
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• pp.466-475
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• 1997

I examined arbuscular mycorrhizal(AM) fungus inoculation effects on the seedling growth of Korean ash tree(Fraxinus rhynchophylla Hance), which distributes in fertile mesic soils, under a seven-day watering cycle of water stress and compost-added fertile conditions. Three Korea-native AM fungi were inoculated : an unidentified Glomus species, Gigaspora margarita Becker & Hall and Scutellospora heterogama(Nicol. & Gerd) Walker & Sanders from disturbed forest soils. The effect of AM fungus inoculation on the seedling varied depending upon fungal species and soil conditions. AM formation was 27 to 65% by the Glomus without forming spores, 47 to 74% with about 10 spores per 20g soil by G. margarita and about 65% with 35 spores by S. heterogama. The soil conditions did not affect either AM or spore formation. The Glomus inoculation increased shoot N and P concentrations, but did not affect seedling growth. G. margarita increased shoot N and P, irrespective of soil conditions, in general, but S. heterogama increased N under water stress and Pin the control soil only. These two fungi significantly increased seedling growth in both control and water stress soils. Compost addition increased the growth of non-mycorrhizal seedlings and offset AM fungus inoculation effects. The relative field mycorrhizal dependency(RFMD) of the seedlings was significant only in control and water stress soils by over 40% in G. margarita or S. heterogama AM plants. Under water stress RFMD was the most evident in S. heterogama AM plants. I conclude that some AM fungi such as G, margarita and S. heterogama can broaden the niche of Korean ash seedlings to a water stress or nutrient poor site but less likely to more fertile sites.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• 제21권12호
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• pp.715-732
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• 2009

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

• Journal of Ginseng Research
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• 제23권3호
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• pp.123-129
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• 1999

Under the light condition of 25,000 Lux (12 hrs dark and light cycle) with scrapping treatment of aerial mycelia of Cylindrocarpon destructans on potato dextrose agar (PDA), V-8 juice agar, and ginseng extract agar, production of the macroconidia was increased to $3.7\~8.1$ fold over them produced in the dark. They were also produced $7.7\~18.0$ times more in the liquid cultures under the light condition than under the dark as well. PDA and V-8 juice agar among the tested were the best for the macroconidium production. On PDA, 1,585 $macroconidia/mm^2$ were produced under the light of 25,000 Lux with scrapping treatment of aerial mycelia of C. destructans, which is 3.2 and 1.4 times more than those produced under 3,000 and 10,000 Lux, respectively. Meanwhile, $20\~99$ macroconidia/$mm^2$ were produced by the non-scrapping under the light condition between 3,000 Lux and 25,000 Lux. The macroconidia were, however, lysed at $6\~7$ days after being incubated under the above range of the light. They were consisted of $1\~3$ cells in a macroconidium while $69.4\~100\%$ of them were the two-celled and the number did not seem to be affected by either the scrapping or the light. Production of chlamydospore converted from mycelia of C. destructans seemed to be promoted by the light and the scrapping as well. The 1,285 chlamydospres/$mm^2$ were produced with the light (25,000 Lux), which is 2.8 and 1.2 times more than those with 3,000 and 10,000 Lux, respectively. Scrapping the aerial mycelia of the cultures increased the chlamydospore formation to 1.9, 2.5 and 1.4 times more than the non-scrapping under the light intensity of 3,000 Lux, 10,000 Lux, and 25,000 Lux, respectively. On PDA, 1 to 8 chlamydospore(s) per catena were formed by all treatments tested and $34.2\~58.9\%$ of them was a single chlamydospore, However, the numbers was affected by neither the light ($3,000\~25,000$ Lux) nor the scrapping the aerial mycelia.

• Korean journal of applied entomology
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• 제59권2호
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• pp.153-163
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• 2020

This study was conducted to evaluate the fitness of Tetranychus kanzawai Kishida on different host plants: young and old leaves of the mandarin orange 'shiranuhi' ((Citrus unshiu × C. sinensis) × C. reticulata), Japanese violet (Viola japonica Langsd.) and kidney bean (Phaseolus vulgaris L.). The development and oviposition experiments were conducted at constant temperatures (20, 25 and 30℃) and a life table parameters were estimated. T. kanzawai could complete it's development on 'shiranuhi' young leaves, japanese violet and kidney bean, while all died during the immature period on 'shiranuhi' old leaves. The total developmental period of T. kanzawai feeding on 'shiranuhi' young leaves was 17.4, 13.4 and 10.2 days at each temperature, respectively, which was longer than 16.1, 9.5 and 7.0 days of kidney bean. The female longevity of T. kanzawai on young leaves of 'shiranuhi' were 19.1, 15.0 and 12.3 days at each temperature, respectively, and there was no significant difference from 22.1, 14.1 and 10.9 days investigated from kidney bean. The fecundity was 18.1, 23.9 and 17.8 eggs per female, which was less than them of japanese violet and kidney bean at each temperature, respectively. As a result of estimating the life table parameters based on the experimental data, intrinsic rate of increase (r_m) were significantly different from each other, and appeared in the following order: kidney (0.1542, 0.2563 and 0.3251), japanese violet (0.1087, 0.2007 and 0.2673) and 'shiranuhi' young leaves (0.0868, 0.1002 and 0.1217) at each temperature, respectively. Finally, the management strategy against T. kanzawai in citrus orchards was discussed based on the results.

• Clinical and Experimental Reproductive Medicine
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• 제27권1호
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• pp.31-37
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• 2000

This study was designed to identify the ultrastructural changes of mouse endometrium during peri-implantation period and obtain the fundamental information for the establishment of 3-dimensional culture system of mouse endometrial cells in vitro. The used female ICR mice ($6{\sim}8$ wks) were conducted on pregnant. The biopsies were obtained from whole uterus at cycle day 1 (D1) and day 5 (D5) after hCG injection and mating. The biopsies materials were fixed 2.5% glutaraldehyde and 1% osmium tetroxide. Subsequently, for observation using light and transmission electron microscopy (LM and TEM), they were dehydrated and embedded in Epon and the embedded biopsies were sectioned and stained. For scanning electron microscopy (SEM), the fixed specimens were dehydrated, dried and coated with gold. 1) For LM, the biopsied materials at D5 (late secretory phase) were appeared the extended stromal layer by increased connective tissues and the fully developed endometrial glands and vessels compared with D1 (early secretory phase). 2) For TEM, the mouse endometrium was consisted of 3-layers, a simple polarized columnar epithelial cells, basement membrane and stromal cells. At D5, the distribution of microvilli, endoplasmic reticulum, Golgi body, lipid and glycogen deposits, secretory granules and surface area of basement membrane were increased. 3) For SEM, the degree of folding and microvilli of surface of mouse epithelial cells was became more and more according to the process of secretory phase, and at D5, implantation time of mouse, the appearance of pinopodes as a specific marker of uterine receptivity was found. The uterine pinopodes of mouse were found in narrow sites at the luminal surface, irregularity and appeared the different stages in the same sample. Therefore, these results indicated that the mouse endometrium was experienced dramatic morphological changes during peri-implantation period.