• Title/Summary/Keyword: Chinese science

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Comparison of Rice Growth under Subtropical and Temperate Environments (아열대와 온대 기후 하에서 벼 생육 비교)

  • Park H.K.;Xu Migging;Lee K.B.;Choil W.Y.;Choil M.G.;Kim S.S.;Kim C.K.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.2
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    • pp.45-53
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    • 2006
  • The objectives of this study are to determine the primary yield components responsible for yield differences in a subtropical environment of the Hunan province China and in a temperature environment of Honam province Korea. Field experiments were conducted in a subtropical environment in Hunan province China during 2002 and in a temperate environment in Honam province Korea during 2003. Seven rice cultivars were grown under optimum crop management in each experiment field. Yield, yield components and plant dry matter were determined at maturation. The highest yield (567 kg/10a) was produced at Honam province by Jinyou 207, a Chinese cultivar, The maximum yield at Hunan province was 453 kg/10a by Sanyou 63. On the average across cultivars, Honam produced 23% greater yields than Hunan. Sink size (spikelets per $m^2$) was responsible far these yield differences. Panicle number per $m^2$ was much greater at Honam.

Thought Experiments: on the Working Imagination and its Limitation (사고실험 - 상상의 작용과 한도에 대해)

  • Hwang, Hee-sook
    • Journal of Korean Philosophical Society
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    • v.146
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    • pp.307-328
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    • 2018
  • The use of thought experiments has a long history in many disciplines including science. In the field of philosophy, thought experiments have frequently appeared in the pre-existing literature on the contemporary Analytic Philosophy. A thought experiment refers to a synthetic environment where the designer of the experiment-with his or her intuition and imagination-tests common-sense knowledge. It can be understood as a conceptual tool for testing the validity of the common understanding of an issue or a phenomenon. However, we are not certain about the usefulness or efficacy of a thought experiment in knowledge production. The design of a thought experiment is meant to lure readers into believing as intended by the experiment itself. Thus, regardless of the purpose of a thought experiment, many readers who encounter the experiment could feel deceived. In this paper, to analyze the logic of thought experiments and to seek the source of uneasiness the readers and critics may feel about thought experiments, I draw lessons from three renowned thought-experiments: Thomson's 'ailing violinist', Putnam's 'brain in a vat', and Searle's 'Chinese room'. Imaginative thought experiments are usually constructed around a gap between the reality and the knowledge/information at hand. From the three experiments, several lessons can be learned. First, the evidence of the existence of a gap provided via thought experiments can serve as arguments for counterfactual situations. At the same time, the credibility and efficacy of the thought experiments can be damaged as soon as the thought-experiments are carried out with inappropriate and/or murky directions regarding the procedures of the experiment or the background of the study. According to D. R. Hofstadter and D. C. Dennett(1981), the 'knob setting' in a thought experiment can be altered in the middle of a simulation of the experimental condition, and then the implications of the thought experiment change altogether, indicating that an entirely different conclusion can be deduced from thought experiment. Lastly, some pre-suppositions and bias of the experiment designers play a considerable role in the validity and the chances of success of a thought experiment; thus, it is recommended that the experiment-designers refrain from exercising too much of their imagination in order to avoid contaminating the design of the experiment and/or wrongly accepting preconceived/misguided conclusions.

Schematic Maps of Ocean Currents in the Yellow Sea and the East China Sea for Science Textbooks Based on Scientific Knowledge from Oceanic Measurements (관측 기반 과학적 지식에 근거한 과학교과서 황해 및 동중국해 해류모식도)

  • PARK, KYUNG-AE;PARK, JI-EUN;CHOI, BYOUNG-JU;LEE, SANG-HO;SHIN, HONG-RYEOL;LEE, SANG-RYONG;BYUN, DO-SEONG;KANG, BOONSOON;LEE, EUNIL
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.22 no.4
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    • pp.151-171
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    • 2017
  • Most of oceanic current maps in the secondary school science and earth science textbooks have been made on the base of extensive in-situ measurements conducted by Japanese oceanographers during 1930s. According to up-to-date scientific knowledge on the currents in the Yellow Sea and the East China Sea (YES), such maps have significant errors and are likely to cause misconceptions to students, thus new schematic map of ocean currents is needed. The currents in the YES change seasonally due to relatively shallow water depths, complex terrain, winds, and tides. These factors make it difficult to construct a unified ocean current map of the YES. Sixteen major items, such as the flow of the Kuroshio Current into the East China Sea and its northward path, the origin of the Tsushima Warm Current and its path into the Korea Strait, the path of Taiwan Warm Current, the Jeju Warm Current, the runoff pattern of the Yangtze River flow, the routes of the northward Yellow Sea Warm Current, the Chinese Coastal Current, and the West Korea Coastal Current off the west coast of the Korean Peninsula, were selected to produce the schematic current map. Review of previous scientific researches, in-depth discussions through academic conferences, expert discussions, and consultations for three years since 2014 enabled us to produce the final ocean current maps for the YES after many revisions. Considering the complexity of the ocean currents, we made seven ocean current maps: two representative current patterns in summer and winter, seasonal current maps for upper layer and lower layer in summer and winter, and one representative surface current map. It is expected that the representative maps of the YES, connected to the current maps of the East Sea and the Northwest Pacific Ocean, would be widely utilized for diverse purposes in the secondary-school textbooks as well as high-level educational purposes and even for scientific scholarly experts.

DEU-7 Derived from Ulmus macrocarpa Improved Immune Functions in Cyclophosphamide-treated Mice (면역억제 마우스 모델에서 왕느릅나무 유래 DEU-7의 면역기능 증강)

  • Kang, Kyung-Hwa;Go, Ji Su;Lee, Inhwan;Lee, Sang Ho;Lee, Sung Do;Kim, Deok Won;Lee, Jong-Hwan;Hwang, HyeJin;Hyun, Sook Kyung;KIM, Byoung Woo;Kim, Chul Min;Chung, Kyung Tae
    • Journal of Life Science
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    • v.25 no.10
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    • pp.1156-1163
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    • 2015
  • The present study investigated the immunomodulatory properties of four different medicinal plants in a cyclophosphamide-treated Balb/c mouse model. One of the four plants, Ulmus macrocarpa, showed partial resistance against immune suppression induced by cyclophosphamide. The bark of U. macrocarpa, commonly known as the Chinese elm, has been used as a pharmaceutical material in Korean traditional medicine to treat bacterial inflammation and induce wound healing. In this study, water extract of U. macrocarpa, named DEU-7, was used for its immunomodulating functional activity. DEU-7 increased the weight of the spleen and the number of splenocytes but did not significantly affect the liver, kidney, and thymus in vivo. A splenocyte viability assay confirmed that DEU-7 influenced ex vivo splenocyte survival. DEU-7 also increased the levels of cytokines, such as IL-2 and IL-4, and immunoglobulins, such as IgM, IgG, and IgA. These results indicated that DEU-7 is involved in the activation of T and B lymphocytes. In addition, DEU-7 was able to maintain the production of cytokines, such as TNF-α, IL-12, and IFN-γ, in the condition of cyclophosphamide-induced immune suppression, suggesting that DEU-7 activated innate immune cells, even under immune suppression. We concluded that DEU-7 aids immunological homeostasis, thereby preventing immune suppression, and aids both innate and adaptive immune response by maintaining the levels of various cytokines and immunoglobulins. Consequently, it is worth investigating the potential of DEU-7 as a supplemental source for immune-enhancing agents.

Microbial and Pathogenic Contamination of Ready-to-eat Fresh Vegetables in Korea (한국에 유통중인 신선편이 채소류의 미생물 품질 및 병원성 세균의 오염도 조사)

  • Bae, Young-Min;Hong, Yu-Jin;Kang, Dong-Hyun;Heu, Sung-Gi;Lee, Sun-Young
    • Korean Journal of Food Science and Technology
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    • v.43 no.2
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    • pp.161-168
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    • 2011
  • The purpose of this study was to evaluate microbiological contamination of fresh vegetables in Korea. Twenty types of vegetables were tested for total aerobic bacteria, coliforms, Escherichia coli, yeast and mold, and pathogenic bacteria such as Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Salmonella, E. coli O157:H7, Cronobacter sakazakii, Shigella, and Campylobacter. Levels of total aerobic bacteria and coliform on 20 vegetables were between 3.74 and 8.04 log CFU/g, and 0.16 and 5.02 log CFU/g, respectively. The highest contamination levels of total aerobic bacteria were observed on water dropwort, sprouts, mungbean sprout, and ballflower root. There was no significant difference (p>0.05) in microbial contamination levels of total aerobic count, coliform, E. coli, yeast and mold between organic and nonorganic vegetables. When isolation methods using selective agars were applied, L. monocytogenes, B. cereus, Salmonella and Campylobacter were isolated from some fresh vegetable samples. Results of API kit tests showed that L. monocytogenes was identified on Chinese cabbage, cucumber, soybean sprouts, and iceberg lettuce while Salmonella was identified on Korean leek. Furthermore, Campylobacter jejuni was also identified in more than 50 of the 100 samples. However, when positive samples from API kit were tested for real-time PCR or 16S rRNA sequencing method, only B. cereus from perilla leaf, carrot, water dropwort, and sprouts showed positive results. These results indicate that selective agar and API kit detection methods might result in false positive results for some pathogens. Therefore, studies need to improve isolation or confirmation methods for such pathogens.

Components and Biological Activity of Aqueous Extract Isolated from Winged Stem of Euonymus alatus (화살나무 물 추출물의 구성성분과 생리활성)

  • Oh, Bong-Yun;Hwang, Soo-Kyung;Cheong, Mi-Young;Sin, Hong-Sig;Park, Bock-Hee;Lee, Jeong-Ho;Kim, Soo-Hyun
    • Korean Journal of Food Science and Technology
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    • v.37 no.6
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    • pp.898-904
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    • 2005
  • Although Euonymus alatus (EA) has been used as traditional medicine for cancer treatment, exact substances involved in curing of the disease are not yet known. Free radical scavenging and reactive oxygen species (ROS) removal activities of aqueous extract components isolated from winged stem of EA in animal cell line were investigated. Aqueous extract of EA (AEEA) was fractionated by ultrafiltration. All fractions mainly consisted of polysaccharide (44.8%), protein (2.1%), small amounts of phenol compounds and organic acids. Antioxidant activity of AEEA increased depending on concentration fractions, as determined by 1,1-diphenyl-2-picrylhydrazyl method. ROS removal activity was visualized in Chinese hamster ovary cell line using laser scanning confocal microscope, and AEEA activity increased in order of F IV>F III>F I>F II. These results suggest AETA has bioactive carbohydrates with potentials as functional foods and antioxidants.

Anti-inflammatory Efficacy and Liver Protective Activity of Pine Pollen according to Probe Sonicator Ultrasonic Disintegration Extraction Method (송화분의 초음파 파쇄 추출 방법에 따른 항염증 효능 및 간 보호 활성)

  • Kim, Ok Ju;Woo, Young Min;Jo, Eun Sol;Jo, Min Young;Li, Chun-Ri;Lee, Young-Ho;Ahn, Mee Young;Lee, Sang-Hyeon;Ha, Jong Myung;Kim, Andre
    • Applied Chemistry for Engineering
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    • v.30 no.5
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    • pp.569-579
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    • 2019
  • In this study, the effect anti-oxidant, anti-inflammatory, and liver protective activity was investigated via quick ultrasonic disintegration of pine pollen using a probe sonicator (PS) followed by the extraction with water, 70% ethanol, and 100% ethanol. The anti-inflammatory effect was studied by measuring the production of nitric oxide (NO) and cytokine in RAW264.7 cells induced with lipopolysaccharides (LPS). The cell toxicity was also checked with an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the experiment was conducted using non-toxic $100{\mu}g/mL$. The NO inhibition rate was highest in the 70% ethanol PS group at $85.99{\pm}0.12%$. Also an excellent efficiency was obtained from the results of interlukin-1 beta ($IL-1{\beta}$) and tumor necrosis factor alpha ($TNF-{\alpha}$), which is related to inflammation-related cytokine, with the respective inhibition rates of 63 and 22%. To examine liver protective activity, HepG2 cells were treated with Taclin, and the generation of glutamic oxaloacetic transaminase (GOT) and lactate dehydrogenase (LDH) was measured in the culture solution. From GOT and LDH generation results, the inhibition rates in the 70% ethanol PS group were 28% and 13%, respectively, which was higher compared to that of using negative control group. Our results suggest that pine pollen extracted in 70% ethanol using PS may be used to develop food products that have anti-aging, anti-inflammatory, and liver protective effects.

Soil Microbial Flora and Chemical Properties as Influenced by the Application of Pig Manure Compost (돈분퇴비의 시용이 배추재배지 토양의 미생물상 및 화학성에 미치는 영향)

  • Weon, Hang-Yeon;Kwon, Jang-Sik;Suh, Jang-Sun;Choi, Woo-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.1
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    • pp.76-83
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    • 1999
  • Studies were conducted during 2 months from May of 1997 to evaluate the effects of pig manure compost(PMC) on soil microbial flora. To do so, a field experiment of Chinese cabbage(Brassica campestris L.) was conducted in a randomized block design on a sandy loam soil and microbial floral characteristics in soils were analyzed. Treatments to control included the application of PMC at (A) $8Mg\;ha^{-1}$CM-8), (B) $29Mg\;ha^{-1}$(CM-2,9), and (C) $57Mg\;ha^{-1}$(CM-57), and of chemical fertilizer(D) at $320N-80P_2O_5-200K_2O\;kg\;ha^{-1}$(NPK). In each treatment, the rhizosphere and non-rhizosphere soils were tested for the analysis of microbial populations. The populations of bacteria, actinomycetes, and fungi increased in soils with the applications of PMC and chemical fertilizer, but that of Bacillus sp. decreased. However, the population of fluorescent Pseudomonas sp. was reduced in NPK plots only. With increasing application rates of PMC, the number of colony forming units(cfu) of bacteria (Pseudomonas sp. and actinomycetes) and fungi increased. in all PMC-treated plots, the population density peaked at early growth stage for bacteria(including Bacillus sp.), at late growth for fluorscent Pseudomonas sp., and at harvest for fungi and actinomycetes. The rhizosphere effect was greatest for fluorscent Pseudomonas sp. As the application rates of PMC increased, Total N, organic matter, available phosphate, and exchangeable -K, -Ca, and -Mg increased compared to control, but soil pH was lowered. In NPK plots, EC was 3.4-fold and exchangeable K was 5-fold higher than control.

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Geophysical Study on the Ultramafic Rocks of Chungnam Province, Korea: Characteristics of Seismic Velocity (충남지역 초염기성 암체의 지구물리학적 연구: 탄성파 속도 특성)

  • Suh, Man-Cheol;Woo, Young-Kyun;Song, Suck-Hwan;Tianyao, Hao
    • Journal of the Korean earth science society
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    • v.21 no.3
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    • pp.349-358
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    • 2000
  • Compressional and shear wave velocities (Vp and Vs) and densities have been measured for serpentinite, amphibolite, amphibole and biotite schist, and gneiss from western part of Chungnam Province at room temperature. Ranges of the density are 2.6${\sim}$2.86g/cm$^3$ for serpentinite, 2.25${\sim}$2.81g/cm$^3$ for talc, and 2.74${\sim}$3.07g/cm$^3$ for metamorphic rocks. Of these rocks, talc shows wider ranges than serpentinite and amphibolites due to its metamorphic process from serpentinite. Values of Vp and Vs are 5719${\sim}$6062m/s and 2898${\sim}$3351m/s for serpentinites, 4019${\sim}$5478m/s and 2241/${\sim}$2976m/s for talc, 5375${\sim}$6372m/s and 3042${\sim}$3625m/s for amphibolite, 5290${\sim}$5499m/s and 2968${\sim}$3137m/s for schist, and 4788m/s and 2804m/s for gneiss, respectively. Velocity of P wave increases 1.47 times faster than S wave with increase of density. The results of seismic velocity measurement show anisotropy, higher velocity across than along the schistocity of rocks, especially in metamorphic rocks. This fact indicates that there were regional metamorphism related with tectonic forces. Values of seismic velocity increase with increasing pressure from 20 MPa to 70 MPa, especially in metamorphic rocks. Overall recalculated Vp and Vs values suggest that the serpentinite indicates for upper mantle in the respects of seismic characteristics, in spite of high degree of serpentinization. In addition, those of the amphibolite do for low crust, and gneiss and schist for upper crust.

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Effects of Iron from an Amino Acid Complex on the Iron Status of Neonatal and Suckling Piglets

  • Wei, K.Q.;Xu, Z.R.;Luo, X.G.;Zeng, L.L.;Chen, W.R.;Timothy, M.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.10
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    • pp.1485-1491
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    • 2005
  • This experiment was conducted to investigate the effects of iron from an amino acid complex (Availa-$Fe^{\circledR}$) on the iron status of neonatal and suckling piglets. A total of 24 gestating sows (Landrace${\times}$Large White) were randomly allocated to three dietary treatments. The control diet contained 80 mg $kg^{-1}$ Fe from ferrous sulfate heptahydrate ($FeSO_4$.$7H_2O$), while the two experimental diets were supplemented with an additional 120 mg $kg^{-1}$ Fe from Availa-$Fe^{(R)}$ or $FeSO_4$.$7H_2O$, respectively. The lactating sows remained the same iron treatments as gestating sows, while neonatal piglets of 24 litters born from the above sows were allotted to another three treatments. Piglets from the sows of the control treatment were fed basal diet with no supplemental Fe as control treatment, but were injected with 100 mg Fe as Fe dextran at birth. Piglets from the sows of Availa-$Fe^{(R)}$ or $FeSO_4$.$7H_2O$ treatments were supplemented with 120 mg $kg^{-1}$ iron from Availa-$Fe^{(R)}$ or $FeSO_4$.$7H_2O$, respectively. The total born alive and weaned, and the average piglets weight at birth and at weaning were not significantly affected by the sow' dietary treatments (p>0.05). Iron from Availa-$Fe^{(R)}$ did not demonstrate a statistically significant improvement in hemoglobin concentration, hematocrit and plasma iron of sows on day 90 and 105 of pregnancy and the milk iron of sows during lactation (p>0.05). Neonatal piglets in the Availa-$Fe^{(R)}$ treatment had a significantly higher hemoglobin concentration (p<0.05) and higher hematocrit and plasma iron (p>0.05) than those in the other two treatments, respectively. The hemoglobin of suckling piglets in the Availa-$Fe^{(R)}$ treatment was higher than that of piglets in $FeSO_4$.$7H_2O$ treatment on day 28 (p<0.05). The total iron binding capacity of piglets in Availa-$Fe^{(R)}$ treatment was lower than that of piglets in the control and $FeSO_4$.$7H_2O$ treatment on day 14 (p<0.05), but there was not a statistically significant difference among three treatments on day 28 (p>0.05). However, the hemoglobin and hematocrit of suckling piglets injected with Fe were higher than those of piglets in the other two treatments (p<0.05). This study indicated that the addition of 120 mg $kg^{-1}$ iron from amino acid complex into the diets improved iron status of neonatal and nursing piglets more effectively than the addition of 120 mg $kg^{-1}$ iron from $FeSO_4$.$7H_2O$, however, this improvement of the organic Fe was not sufficient to replace the Fe injection for prevention of iron-deficiency anemia.