• Title/Summary/Keyword: Study design

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Effect of Immune System on Retrovirus-Mediated Herpes Simplex Virus Thymidine Kinase Gene Therapy (면역체계가 Retroviral Vector로 이입한 Herpes Simplex Virus Thymidine Kinase 유전자치료에 미치는 영향)

  • Park, Jae-Yong;Joo, So-Young;Chang, Hee-Jin;Son, Ji-Woong;Kim, Kwan-Young;Kim, Keong-Seok;Kim, Chang-Ho;Park, Jae-Ho;Lee, Jong-Ki;Jung, Tae-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.2
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    • pp.229-240
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    • 1999
  • Background: The impact of the immune response on cancer gene therapy using viral vectors to deliver a "suicide gene" is currently unclear. A vigrous immune response targeted at viral proteins or transgene may enhance the efficacy of tumor destruction and even augment responses to tumor antigens. These responses may involve the release of cytokines and stimulation of tumor specific cytotoxic T-lymphocytes that enhance therapeutic efficacy. On the other hand, a vigorous rapid cellular immune response may destroy cells expressing the therapeutic gene and attenuate the response to therapy. Furthermore, development of neutralizing antibody responses may prevent readministration of virus, a potentially significant limitation. Evaluating the significance of these limitations in animal models and developing solutions are therefore of obvious importance. Methods: After retroviral transduction of mouse mesothelioma cell line(AB12) with Herpes Simplex Virus thymidine kinase (HSVtk) gene in vitro, subcutaneous flank tumors were established. To study the effect of intact immune system on efficacy of tumor erradication, the ability of the HSVtk/ganciclovir system to inhibit tumor growth was compared among normal Balb/c mice, immunodeficient Balb/c-nude and SCID mice, and Balb/c mice immunosuppressed with cyclosporin. Results: Ganciclovir treatment resulted in greater inhibition of tumor growth in Balb/c mice compared with immunodeficient Balb/c-nude mice and SCID mice(in immunodeficient mice, there were no growth inhibition by ganciclovir treatment). Ganciclovir treatment resulted in greater inhibition of tumor growth in noncyclosporin (CSA) treated Balb/c mice compared with CSA treated Balb/c mice. On day 8, mean ganciclovir-treated tumor volume were 65% of control tumor volume in Balb/c mice versus 77% control tumor volume in CSA-treated Balb/c mice. This effect was still evident during therapy (day 11 and 13). On day 13, non-CSA treated tumor volume was 35% of control tumor volume versus 60% of control tumor volume in CSA treated Balb/c mice. Duration of expression of HSVtk was not affected by the immunosuppression with CSA. Conclusion: These results indicate that the immune responses against retrovirally transduced cells enhance the efficacy of the HSVtk/ganciclovir system. These findings have important implications for clinical trials using currently available retrovirus vectors as well as for future vector design.

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Survey of ICT Apply to Plastic Greenhouse, Rack·Pinion Adaption to Single Span and CFD Analysis (온실 ICT융복합 실태조사와 복숭아형 랙피니언천창 적용 단동온실 및 CFD 유동해석)

  • Cho, Kyu Jeong;Kim, Ki Young;Yang, Won Mo
    • Journal of Bio-Environment Control
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    • v.24 no.4
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    • pp.308-316
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    • 2015
  • This study was conducted to investigate the situation of ICT apply to plastic greenhouse, and the results be apply to design of new one. A CFD analysis were conducted to monitering the ventilation and energy saving of the single span greenhouse newly designed. The causes of delay to apply ICT to plastic greenhouse are the high cost for installation(24%), insufficiency of after services(19%), often disorder(16%), unskillful management of soft ware(15%), insufficient ICT efficiency(13%) and unsatisfying of income increase(12%). The parts of problem occurred in ICT plastic greenhouse are the structure, actuator, environmental control system and sensor(approximate 14%, respectively), remote control technique(13%), plant management technique(12%), energy saving technique(10%) and utilization of software(8%). In the condition of lateral window closed, the average wind speed changed to slow, but it was faster in the condition of leeward side window opened than in the condition of lee and winward side window opened. The air movement in the condition of lateral window closed occur by air moving fan not by out air. It is not affect the room temperature but effective the uniformity of room temperature. The average temperature of low height greenhouse was uniform than high height one. The average temperature in condition of 3rd curtain opened become same with outside temperature after 2 hours, but take more 5 hours in condition of 3rd curtain closed.

Effect of Shading Level on Growth and Morphological Characteristics of Ligularia fischeri Seedling (차광수준이 곰취 유묘의 생장 및 형태적 특성에 미치는 영향)

  • Song, Ki Seon;Jeon, Kwon Seok;Kim, Chang Hwan;Yoon, Jun Hyuck;Park, Yong Bae;Kim, Jong Jin
    • Journal of Bio-Environment Control
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    • v.23 no.2
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    • pp.88-94
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    • 2014
  • This study was carried out to survey the early growth characteristics of Ligularia fischeri, plants of half-shaded grounds, primarily used as functional wild edible greens and examine its shading treatment to transplant seedling. The shading treatment was regulated with the shading level(full sunlight, 35%, 50%, 75%, and 95% of full sunlight). According to the experiment, the height was the highest under 75% of shading (17.3 cm), and root diameter was the highest under full sunlight (2.13 mm). It was found that fresh weight (leaf, shoot, root and whole) was the highest (1.784 g, 1.330 g, 0.791 g, 3.905 g respectively ) under 50% of shading. In case of dry weight, leaf, shoot and whole dry weight were surveyed the highest under 35% of shading, and root dry weight was the highest under full sunlight. It was found that S/R ratio and moisture contents (leaf, shoot, root and whole) were the highest under 95% of shading. Leaf area was the highest under 50% of shading ($39.3cm^2$) and the higher shading level, the higher SLA and LAR. It was surveyed that the higher shading level, the thinner leaf thickness. In case of root characteristics, it was showed that the relatively high height growth under 35%~75% of shading, excepting 95% of shading. As a result of surveying the whole experiment, it is concluded that the early growth of L. fischeri is more effective in producing it under 50% of shading.

Improvement of Heat Pump Heating Performance by Selective Heat Storage Using Air Heat of Inside and Outside Greenhouse (온실 내외부 공기열의 선택적 축열에 의한 히트펌프 난방성능 개선)

  • Kwon, Jin Kyung;Kim, Seung Hee;Jeon, Jong Gil;Kang, Youn Koo;Jang, Kab Yeol
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.353-360
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    • 2017
  • In this study, the design and performance test of the air to water heat pump capable of producing hot water for greenhouse heating by using the surplus solar heat inside the greenhouse and the air heat outside greenhouse as the selective heat source were conducted. The heat storage operations using the surplus solar heat and the outside air heat were designed to be switched according to the setting temperature of the greenhouse in consideration of the optimum temperature range of the crop. In the developed system, it was possible to automatically control the switching of heat storage operation, heating and ventilation by setting 12 reference temperatures on the control panel. In the selective heat storage operation with the surplus solar heat and outside air heat, the temperature of thermal storage tank was controlled variably from $35^{\circ}C$ to $52^{\circ}C$ according to the heat storage rate and heating load. The heat storage operation times using the surplus solar heat and outside air heat were 23.1% and 30.7% of the experimental time respectively and the heat pump pause time was 46.2%. COP(coefficient of performance) of the heat pump of the heat storage operation using the surplus solar heat and outside air heat were 3.83 and 2.77 respectively and was 3.24 for whole selective heat storage operation. For the comparative experiment, the heat storage operation using the outside air heat only was performed under the condition that the temperature of the thermal storage tank was controlled constantly from 50 to $52^{\circ}C$, and COP was analyzed to be 2.33. As a result, it was confirmed that the COP of the heat storage operation using the surplus solar heat and outside air heat as selective heat source and the variable temperature control of the thermal storage tank was 39% higher than that of the general heat storage operation using the outside air heat only and the constant temperature control of the thermal storage tank.

A Study on the Fatigue Strength of the Welded Joints in Steel Structures(II) (강구조물(鋼構造物)의 용접연결부(鎔接連結部)의 피로강도(疲勞强度)에 관한 연구(研究)(II))

  • Park, Je Seon;Chung, Yeong Wha;Chang, Dong Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.6 no.1
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    • pp.1-11
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    • 1986
  • Welded connectors of the cover plates, the transverse stiffeners of the plate girders, and the gusset plates of the plates girders or box girders, were selected as studying objects. A simplified method of drawing the S-N curves in these welded joints by a computer program without the direct fatigue tests was established. The plots on the S-N curve using the values from the practical fatigue tests were compared with the results from the method of the computer programming. The results of these studies are as follows. It appeared that the fatigue life by calculation method was a little less than the practical fatigue life from the actual tests. The latter values included both life $N_c$ of occurrence of initial crack $a_i$ and the life $N_p$ of propagation of critical crack. On the other hand, the former values included only the life $N_p$. Therefore, these results should be considered as justifiable ones. Since the difference between the two results was not significant, the results by calculation method should be in the conservation side when the safety of the structures was considered. Consequently, the results by calculation method should be applicable to the fracture fatigue design of structure. For reference, the same fatigue tests were performed with the specimens of 3 pieces in each case made of the low-strength steel, SS 41. The results went unexpected showing that the fatigue strength was lower in the case of low-strength steel. That is, in the case of the cover plate, the fatigue strength became slowly higher than the case of high-strength steel, SWS 50. That was observed when the maximum testing stress was higher than $14kg/mm^2$. In addition, in the case of the transverse stiffener, the fatique strength became rapidly higher than the case of SWS 50. That was observed when the maximum testing stress was lower than $31kg/mm^2$. It was thought that more such fatigue tests should be performed for more reliable results.

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Effect of Feeding Aflatoxin $B_1$ and Vitamin $D_3$ on Metatarsus Bone Minerals of Broiler Chicks (Aflatoxin $B_1$과 Vitamin $D_3$ 결여가 Broiler병아리의 중족골 무기물함량에 미치는 영향)

  • 장윤환;여영수
    • Korean Journal of Poultry Science
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    • v.17 no.4
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    • pp.296-302
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    • 1990
  • This study was conducted to investigate the interaction of aflatoxin B$_1$($AFB_1$) and vitamin D$_3$($VD_3$) in broiler chicks. The 336 broiler chicks(Hubbard line) of equally mixed sex were allocated to triplicate 8(2$\times$4 factorial) treatment groups. The 0 or 1ppm of AFB$_1$and 0, 500, 1,000 or 1,500IU/kg of VD$_3$ were supplemented to the basal diet Fourteen broilers of equally mixed sex were allocated to each replica and 24 groups were arranged in a randomized block design After 3 weeks of feeding the metatarsus were collected from the right and left legs of 4 chicks (2 for each sex) per group. The bone ash and minerals were measured. 1. In respect to the fresh weight of metatarsus bone no significant difference was found between 0 and 1ppm $AFB_1$ treatments, however, decreasing trend was recognized when fed increasing level of $VD_3$(P<.01). 2. The ash content in non-fat dry metatarsus bone decreased when fed 1ppm $AFB_1$(P<.01). However, that increased according to the increasing amount of $VD_3$(P<.01). Although there was no interaction between $AFB_1$ and $VD_3$ it was shown that the 1500IU/kg of $VD_3$ was neccessary to cover the decrease in ash content of metatarsus. when fed 1ppm of $AFB_1$. 3. The Ca contents in metatarsus were not influenced by feeding $AFB_1$ but an increasing trend was verified by feeding increasing levels of $VD_3$(P<.05). 4. The P content decreased as $AFB_1$ was fed(P<.01), while no response was found when fed'different levels of $VD_3$ 5. The Cu content decreased when fed $AFB_1$(P<.05). 6. The Na, Mg, K, Zn, Fe and Mn contents were not affected by feeding $AFB_1$ and /or $VD_3$.

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Effects of Dietary Probiotics on Feed Intakes, Nutrient Digestibility and Nitrogen Retention in Korean Black Goats Fed Two Diets Differing in Forage to Concentrate Ratios (사료 내 조농비율에 따른 생균제의 첨가가 흑염소의 사료섭취량, 영양소 소화율 및 질소축적에 미치는 영향)

  • HwangBo, Soon;Jo, Ik-Hwan;Song, Ki-Jun;Lee, Sung-Hoon
    • Korean Journal of Organic Agriculture
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    • v.15 no.2
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    • pp.195-205
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    • 2007
  • This study was conducted to determine effects of probiotics on performance, nutrient digestibility and nitrogen retention in Korean black goats fed two diets differing in forage to concentrate (F:C) ratio (30:70 and 70:30), for the establishment of their more efficient feeding management system. The probiotics employed in this trial were mixtures of different microbial species, which consisted of Lactobacillus casei, Bacillus subtilis, Saccharomyces cerevisiae, Aspergillus oryzae and Streptomyces griseus. Additional levels of probiotics to each F:C ratio (70:30 or 30:70) were 0 and 0.2%, respectively. Thus, twelve Korean black male goats were allotted to treatments in four groups of three goats per treatment and then they were housed in individual metabolism cages with a randomized complete block design for 21 days. Dry matter (DM) intakes were not affected by dietary F:C ratio and probiotics. Digestible DM amounts were significantly (p<0.05) decreased with increasing levels of dietary forage, but they were not affected by probiotics addition. Dry matter intakes per metabolic body weight and their ratio per body weight had a similar trend to DM intakes with no significant difference by F:C ratio and probiotics addition. The nutrient digestibility was significantly (p<0.05) increased with decreasing levels of forage in the diet, but it was not affected by probiotics addition. Urinary nitrogen loss was significantly (p<0.05) decreased with decreasing levels of dietary forage, but there was no significant difference between probiotics-supplemented and unsupplemented groups within the same F:C ratio. On the contrary, nitrogen retention was decreased with increasing levels of dietary forage, and probiotics supplementation to two diets differing in F:C ratio showed slightly increasing trends in the nitrogen retention. From the above results, probiotics supplementation to two diets differing in F:C ratio did not have the significant influence on feed intakes, nutrient digestibility and nitrogen retention. Consequently, these parameters of Korean black goats were dominated rather by F:C ratio than by dietary probiotics.

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Response Surface Methodology for Optimization of the Removal of Organic Matters in Eutrophic Waters by Korean Freshwater Bivalves (반응표면분석을 이용한 패류의 부영양수 유기물 제어능 연구)

  • Choi, Hwan-Seok;Nam, Gwi-Sook;Kim, Min-Seob;Shin, Hyun-Jae;Park, Myung-Hwan;Hwang, Soon-Jin;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.47 no.4
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    • pp.312-318
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    • 2014
  • This study was conducted to establish models of filtrating rate and production of feces of a native freshwater bivalve, Anodonta woodiana, on removal organic matters in eutrophic waters. Among the applied shell size (4.3~15.5 cm), the filtrating rate and production of feces of Anodonta woodiana was $0.08{\sim}0.86L\;g^{-1}\;h^{-1}$ (average $0.24L\;g^{-1}\;h^{-1}$), $0.00{\sim}11.10mg\;g^{-1}\;h^{-1}$ (average $0.94mg\;g^{-1}\;h^{-1}$), respectively. In two different water current (high $48Lh^{-1}$, low $24Lh^{-1}$), the filtrating rate of Chl-a was $0.02{\sim}0.10L\;g^{-1}\;d^{-1}$ (average $0.05L\;g^{-1}\;d^{-1}$), $0.02{\sim}0.11L\;g^{-1}\;d^{-1}$ (average $0.07L\;g^{-1}\;d^{-1}$) and the removal rate was 65.4%, 82.1%, respectively. Response surface methodology, with a central composite design comprising 3 levels and 2 variables, was used to identify the optimal removal condition of shell length, water current and filtrating rate or feces production by bivalves. The optimum removal conditions were found that had optimized $6.21L\;mussel^{-1}\;d^{-1}$ at shell length 14.3~15.6 and water current $22{\sim}30Lh^{-1}$. The optimal conditions of production of feces ($4.2mg\;g^{-1}\;d^{-1}$) by freshwater mussels were shell length 14.3~16.3 cm and water current $36{\sim}44Lh^{-1}$.

Effects of Dietary Bacillus subtilis Supplementation on Meat Quality, Growth Performance and Fecal Malodor Gas Emission in Finishing Pigs (Bacillus subtilis 급여가 비육돈의 육질 특성, 생산성 및 분내 유해가스 발생에 미치는 영향)

  • Jang, Hae-Dong;Yoo, Jong-Sang;Lee, Je-Hyun;Kim, Hyo-Jin;Shin, Seung-Oh;Hwang, Yan;Zhou, Tain-Xiang;Chen, Ying-Jie;Kang, Dae-Kyung
    • Food Science of Animal Resources
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    • v.28 no.3
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    • pp.327-332
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    • 2008
  • This study was conducted to evaluate the effects of dietary Bacillus subtilis on meat quality, growth performance and fecal malodor gas emission in finishing pigs. Thirty-six pigs (Landrace ${\times}$ Yorkshire ${\times}$ Duroc, $83.53{\pm}1.01\;kg$ average initial body weight) were used in a 35 d growth assay. Dietary treatments were 1) CON (basal diet), 2) B1 (basal diet + B. subtilis 0.1%) and 3) B2 (basal diet + B. subtilis 0.2%). The pigs were distributed into four pigs per pen with three replicate pens per treatments by completely randomized design. For the entire period, the final weight, ADO, ADFI and gain/feed were not significantly different among the treatments. There were no significant differences in meat quality (sensory evalution, meat color, TBARS, water holding capacity, drip loss, cooking loss and M. longissimus dorsi area) among the treatments. $H_2S$ was significantly decreased in B2 treatment compared to CON and B1 treatments (p<0.05). However, ammonia, mercaptans and acetic acid were not significantly different among the treatments. In conclusion, B. subtilis 0.2% treatments decreased fecal $H_2S$ gas emission in finishing pigs.

The Effect of Covering Materials on Prolongation of Green Period in Zoysiagrass and Cool-season Grass in Early Winter (피복이 한국잔디 및 한지형 잔디의 초겨울 녹색기간연장에 미치는 영향)

  • Lee Jae-Pil;Kim Seok-Jeong;Shin Seok-Hoon;Kim Doo-Hwan
    • Asian Journal of Turfgrass Science
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    • v.18 no.3
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    • pp.129-139
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    • 2004
  • This study conducted to find out the best way to prolong green period of Zoysiagrass and Cool-season grass from 1999 to 2001 in Korea. Treatments were control, vinyl, black shade net, green shade net, black shade net+vinyl, green shade net+vinyl, vinyl+black shade net, and vinyl+green shade net for Zoysiagrass. For cool-season grass, treatments were control, non-punched vinyl and punched vinyl. Data on temperature, light intensity, humidity, leaf color and chlorophyll were collected. Plot size was 2 by 2 and the experiment was conducted using completely randomized design with three replication. Zoysiagrass Green period of Zoysiagrass depended on temperature and light intensity than humidity. Effective method of prolongation of green period in Zoysiagrass was to covered it with vinyl during early October to early November, and then using vinyl+black shade net from end of November. Cool-season grass Effective method of prolongation of green period in Cool-season grass was by covering it with vinyl during mid-November to mid-December, and then using vinyl+black shade net from end of December.