• Title/Summary/Keyword: ${\pi}$

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Differentiation of Korean isolates of Entamoeba histolytica from Entamoeba dispar (우리 나라에서 분리한 이질아메바(Entamoeba histoItica)와 동형아메바(Entamoebn dispar)의 감별)

  • 최성준;이미정
    • Parasites, Hosts and Diseases
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    • v.34 no.1
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    • pp.15-20
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    • 1996
  • Cysts of Entamoebn histoIMtica are still found from humans in Korea, but notall of the cysts are known as pathogenic. The non-pathogenic strain is regarded as a differenL species, E. nispnr. In this study, Korean isolates of conventional E. histolvticn were subjected for the differentiation by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis. Human stools were screened by routine microscopic examination, and cyst or trophozoite positive stools were inoculated into Robinson media. The cultivated trophozoites were prepared for DNA extraction, and the DNAs were used for PCR with common primers of Pl gene. The PCR products were divested with 3 restriction enzymes and RFLP was observed. Also anti-sense primers containing the cleavage site of each restriction eWe were designed for differentiation only by PCR. The PCR products of Korean isolates 59,512, YS-6, and YS-27 were spliced by Taq I and Xmnl but not byAccl, and the isolates S1, S3, S11, S15, S16, S17, S20, YS- l7, and YS-44 were spliced by Acc I but not by Taq I and Xmn I. These RFLP pattern correlated well with PCR products by the species specific primers. The findings confirm that the Korean isolates 59,512, YS-6, and YS-27 are E. histolwtico and others are E. dispar. In Korea, most of the asymptomatic cyst carriers are infected by E. dispar, not by E. histolytica. Key words: Entcmoebc histolytica, Entcmoebn dispar Korean isolates, polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP)

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Current Status of processing and Research Trends in Ginseng Products (인삼제품의 가공현황과 연구 동향)

  • 양재원
    • Journal of Ginseng Research
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    • v.20 no.4
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    • pp.501-519
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    • 1996
  • There are two kinds of commercially available ginseng root, red ginseng and white ginseng processed from fresh ginseng root Those ginsengs are primary product from fresh ginseng root and have the characteristic of keeping their original root shape Processed ginseng products are made from either red ginseng or white ginseng by way of complicated process of pulverization. Extraction. Condensation, fettering, sterilization, etc. Among them there are extracts. extract powder, powder, capsules tablets, Candy, drinks, nectar, jelly, gums. chicken soup. tonic. etc. to meet the demand for consumer's pretheronce . The 200 kinds of processed secondary products are approximately produced in the form of 20 kinds of ginseng products by about 60 domestic companies. In spite of about 213.000 million won of domestic market in 1993. it seems like that the ginseng market of the future has not a good prospects The total market sale of white ginseng in Korea has been continuously decreased since 1991 And 963 tons of white ginseng was consumed in domestic market in 1993 The domestic market sales of white ginseng in origina1 root shave. was 90, 000 million won in 1993 and market price of the fine root used as a source of processed products has not been changed in these ten years. The total market sale of red ginseng and its processed products was 58, 000 million won in 1993 9.800 mi11ion won of red ginseng in original root shape and 48.000mi11ion of processed red ginseng product. Ginseng products such as extracts, drinks, teas and tonics etc atre mostly exported to south-east Asia. And the total exports of ginseng pi.oducts (extracts, drinks teas) decreased to 54 million dollars in 1994, compared with 85 million dollars in 1992. Despite of extensive knowledge about ginseng little is still known about the development of new processed ginseng pl.oducts because of "Know-How". Some papars have presented the effects of extracting method(amounts of solvent. time. temperature, equipment. etc.) on the quality and yields of ginseng extr acts. Also. some researchers have carried out a few studies on the poriflcation of the extracts and the amounts of precipitation in the drink at variotas pH during the storage for preventinly drink from precipitation. A fell studies on the preservation of Korean ginseng powder. tea. Extract powder by irradiation and ozone treatment have been reported by some researcher for the improvement hygienic quality of ginseng products There are also some reports about the effects of ginseng components on the acid production by lactic acid bacteria or acetic acid bacteria. and alcohol production by yeast for the development of new ginseng products processed by fermentation. To make ginseng more able to contribute to the health of mankind in the future. consistent and considerable efforts should be focussed on improving the taste of ginseng and developing various new product as a health food or a function food.tion food.

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Constitutive Activation of $p70^{S6k}$ in Cancer Cells

  • Kwon, Hyoung-Keun;Bae, Gyu-Un;Yoon, Jong-Woo;Kim, Yong-Kee;Lee, Hoi-Young;Lee, Hyang-Woo;Han, Jeung-Whan
    • Archives of Pharmacal Research
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    • v.25 no.5
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    • pp.685-690
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    • 2002
  • The mitogen-stimulated serine/threonine kinase $p70^{S6k}$ plays an important role in the progression of cells from $G_0/G$_1$$ to S phase of the cell cycle by translational up-regulation of a family of mRNA transcripts family of mRNA transcripts which contain polypyrimidine tract at their 5 transcriptional start site. Here, we report that $p70^{S6k}$ was constitutively phosphorylated and activated to various degrees in serum-deprived AGS, A2058, HT-1376, MG63, MCF7, MDA-MB-435S, MDA-MB-231 and MB-157. Rapamycin treatment induced a significant dephosphorylation and inactivation of $p70^{S6k}$ in all cancer cell lines, while wortmannin, a specific inhibitor of PI3-K, caused a mild dephosphorylation of $p70^{S6k}$ in AGS, MDA-MB-435S and MB-157. In addition, SQ20006, methylxanthine phosphodiesterase inhibitor, reduced the phosphorylation of $p70^{S6k}$ in all cancer cells tested. Consistent with inhibitory effect of rapamycin on $p70^{S6k}$ activity, rapamycin inhibited [$^3H$]-thymidine incorporation and increased the number of cells at $G_{0}G_{1}$ phase. Furthermore, these inhibitory effects were accompanied by the decrease in growth of cancer cells. Taken together, the results indicate that the antiproliferative activity of rapamycin might be attributed to cell cycle arrest at $G_{0}G_{1}$ phase in human cancer cells through the inhibition of constitutively activated $p70^{S6k}$ of cancer cells and suggest $p70^{S6k}$ as a potential target for therapeutic strategies aimed at preventing or inhibiting tumor growth.

Change in Periodontal Status by Professional Toothbrushing, and Patients' Satisfaction (전문가잇솔질에 의한 치주상태 변화와 환자만족도)

  • Kim, Chang-Hee;Kim, Jin;Kim, Chang-Woog
    • Journal of dental hygiene science
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    • v.8 no.4
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    • pp.261-266
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    • 2008
  • The purpose of this study was to examine the effects of the toothpick method, one of professional toothbrushing methods, on the prevention of periodontal diseases and the satisfaction level of patients with that. The subjects in this study were 33 patients who included 16 men and 17 women. After the toothpick method was applied to the selected patients from January 9 to February 28, 2008, the collected data were analyzed with SPSS (Statistical Package for the Social Science) 12.0 program. The findings of the study were as follows: First, the patients investigated showed a 0.71 reduction in PI than in the past. The index of bleeding upon probing stood at 5.12, which dropped from 8.09 in the beginning. Second, the patients gave a mean of 4.20 to the professional toothbrushing out of possible five points, which showed that they expressed satisfaction with that. Third, as for the relationship between general characteristics and satisfaction level, the women were more satisfied with that ($4.25{\pm}0.33$). By age group, those who were in their 60s and up found that more satisfactory ($4.31{\pm}0.30$). Fourth, as to changes in oral symptoms by gender, the largest number of the men and women considered their gums to become healthier after the professional toothbrushing was applied. The above-mentioned findings suggested that dental institutions should be equipped with well-educated oral health care personnels who are responsible for the periodontal health of patients, and the development of oral health promotion programs is urgently required as well.

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Electrooptic Modulator with InAs Quantum Dots (InAs/InGaAs 양자점을 이용한 전계광학변조기)

  • Ok, Seong-Hae;Moon, Yon-Tae;Choi, Young-Wan;Son, Chang-Wan;Lee, Seok;Woo, Deok-Ha;Byun, Young-Tae;Jhon, Young-Min;Kim, Sun-Ho;Yi, Jong-Chang;Oh, Jae-Eung
    • Korean Journal of Optics and Photonics
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    • v.17 no.3
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    • pp.278-284
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    • 2006
  • We have fabricated and measured electrooptic modulator using coupled stack InAs/InGaAs quantum dots. The height of the quantum dot is 16 nm and quantum dots are stacked including an InGaAs capping layer. The peak wavelength of photoluminescence is 1260 nm at room temperature and 1158 nm at 12 K. The operation characteristics of the quantum dots show high modulation efficiency of electrooptic modulator at 1550 nm compared to that of existing III-V bulk and MQW type semiconductor. The measured switching voltage ($V\pi$) is 540 and 600 mV, for TE mode and TM mode, respectively. From the results, the modulation efficiency can be determined as 333.3 and $300^{\circ}/V{\cdot}mm$ for TE and TM modes. The results reported here may lead to the design and fabrication of a novel electrooptic modulator with low switching voltage and high efficiency.

Donor-π-Acceptor Type Diphenylaminothiophenyl Anthracene-mediated Organic Photosensitizers for Dye-sensitized Solar Cells

  • Heo, Dong Uk;Kim, Sun Jae;Yoo, Beom Jin;Kim, Boeun;Ko, Min Jae;Cho, Min Ju;Choi, Dong Hoon
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1081-1088
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    • 2013
  • Two new metal-free organic dyes bridged by anthracene-mediated ${\pi}$-conjugated moieties were successfully synthesized for use in a dye-sensitized solar cell (DSSC). A N,N-diphenylthiophen-2-amine unit in these dyes acts as an electron donor, while a (E)-2-cyano-3-(thiophen-2-yl)acrylic acid group acts as an electron acceptor and an anchoring group to the $TiO_2$ electrode. The photovoltaic properties of (E)-2-cyano-3-(5-((10-(5-(diphenylamino)thiophen-2-yl)anthracen-9-yl)ethynyl)thiophen-2-yl)acrylic acid (DPATAT) and (E)-2-cyano-3-(5'-((10-(5-(diphenylamino)thiophen-2-yl)anthracen-9-yl)ethynyl)-2,2'-bithiophen-5-yl)acrylic acid (DPATABT) were investigated to identify the effect of conjugation length between electron donor and acceptor on the DSSC performance. By introducing an anthracene moiety into the dye structure, together with a triple bond and thiophene moieties for fine-tuning of molecular configurations and for broadening the absorption spectra, the short-circuit photocurrent densities ($J_{sc}$), and open-circuit photovoltages ($V_{oc}$) of DSSCs were improved. The improvement of $J_{sc}$ in DSSC made of DPATABT might be attributed to much broader absorption spectrum and higher molecular extinction coefficient (${\varepsilon}$) in the visible wavelength range. The DPATABT-based DSSC showed the highest power conversion efficiency (PCE) of 3.34% (${\eta}_{max}$ = 3.70%) under AM 1.5 illumination ($100mWcm^{-2}$) in a photoactive area of $0.41cm^2$, with the $J_{sc}$ of $7.89mAcm^{-2}$, the $V_{oc}$ of 0.59 V, and the fill factor (FF) of 72%. In brief, the solar cell performance with DPATABT was found to be better than that of DPATAT-based DSSC.

Fabrication of Supercapacitors using Silver Nano Paste and Gel Electrolyte (은 나노 페이스트와 젤 전해질을 이용한 슈퍼캐패시터 제작)

  • Yoon, Seong Man;Jang, Hyunjung;Kim, Dae Won;Jang, Yunseok;Jo, Jeongdai;Go, Jeung Sang
    • Clean Technology
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    • v.19 no.4
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    • pp.410-415
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    • 2013
  • The supercapacitors were fabricated using silver (Ag) nano paste and activated carbon paste on the polyimide (PI) film and 5% potassium polyacrylate (PAAK) was used for gel electrolyte. In this paper, the current collector film and the electrode film were fabricated using screen printing. The thickness of printed silver paste was $7.3{\mu}m$ and the sheet resistance has the range of $5-7m{\Omega}/square$. An activated carbon with a surface area of $1,968m^2/g$, an electronic conducting agent (SUPER P, TIMCAL) and poly (4-vinylphenol) were mixed in 2-(2-buthoxyethoxy) ethyl acetate (BCA) with a ratio of 7:1:3 to fabricate the electrode paste. To analyze electrochemical characteristics, cyclic voltammetry was performed to evaluate the stability of the devices under the voltage range of -0.5-0.5 V. The calculated specific capacitances were 44.04 and 8.62 F/g for 10 and 500 mV/s scan rates, respectively.

Real-Time Monitoring of Mitochondrial ATP Synthesis and Hydrolysis by Surface Infrared Spectroscopy

  • Yamaguchi, Ryo-Taro;Hirano-Iwata, Ayumi;Aonuma, Yuki;Yoshimura, Yuya;Shinohara, Yasuo;Kimura, Yasuo;Niwano, Michio
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.108-109
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    • 2013
  • Mitochondria play key roles in the production of cell's energy. Their dominant function is the synthesis of adenosine 5'-triphosphate (ATP) from adenosine diphosphate (ADP) and phosphate (Pi) through the oxidative phosphorylation. Evaluation of drug-induced mitochondrial toxicity has become increasingly important since mitochondrial dysfunction has recently been implicated in numerous diseases including cancer and diabetes mellitus. Mitochondrial functions have been monitored via oxygen consumption, mitochondrial membrane potential, and more importantly via ATP synthesis since ATP synthesis is the most essential function of mitochondria. Various analytical methods have been employed to investigate ATP synthesis in mitochondria, including high performance liquid chromatography (HPLC), bioluminescence technique, and pH measurement. However, most of these methods are based on destructive analysis or indirect monitoring through the enzymatic reaction. Infrared absorption spectroscopy (IRAS) is one of the useful techniques for real-time, label-free, and direct monitoring of biological reactions [1,2]. However, the strong water absorption requires very short path length in the order of several micrometers. Transmission measurements with thin path length are not suitable for mitochondrial assays because solution handlings necessary for evaluating mitochondrial toxicity, such as rapid mixing of drugs and oxygen supply, are difficult in such a narrow space. On the other hand, IRAS in the multiple internal reflection (MIR) geometry provides an ideal optical configuration to combine solution handling and aqueous-phase measurement. We have recently reportedon a real-time monitoring of drug-induced necrotic and apoptotic cell death using MIR-IRAS [3,4]. Clear discrimination between viable and damaged cells has been demonstrated, showing a promise as a label-free and real-time detection for cell-based assays. In the present study, we have applied our MIR-IRAS system to mitochondria-based assays by monitoring ATP synthesis in isolated mitochondria from rat livers. Mitochondrial ATP synthesis and hydrolysis were in situ monitored with MIR-IRAS, while dissolved oxygen level and solution pH were simultaneously monitored with O2 and pH electrodes, respectively. It is demonstrated that ATP synthesis and hydrolysis can be monitored by the IR spectral changes in phosphate groups in adenine nucleotides and MIR-IRAS is useful for evaluating time-dependent drug effects of mitochondrial toxicants.

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Development of Composite Sensing Technology Using Internet of Things (IoT) for LID Facility Management (LID 시설 관리를 위한 사물인터넷(IoT) 활용 복합 센싱 적용기술 개발)

  • Lee, Seungjae;Jeon, Minsu;Lee, Jungmin;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.22 no.4
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    • pp.312-320
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    • 2020
  • Various LIDs with natural water circulation function are applied to reduce urban environmental problems and environmental impact of development projects. However, excessive Infiltration and evaporation of LID facilities dry the LID internal soil, thus reducing plant and microbial activity and reducing environmental re duction ability. The purpose of this study was to develop a real-time measurement system with complex sensors to derive the management plan of LID facilities. The test of measurable sensors and Internet of Things (IoT) application was conducted in artificial wetlands shaped in acrylic boxes. The applied sensors were intended to be built at a low cost considering the distributed LID and were based on Arduino and Raspberry Pi, which are relatively inexpensive and commercialized. In addition, the goal was to develop complex sensor measurements to analyze the current state o f LID facilities and the effects of maintenance and abnormal weather conditions. Sensors are required to measure wind direction, wind speed, rainfall, carbon dioxide, Micro-dust, temperature and humidity, acidity, and location information in real time. Data collection devices, storage server programs, and operation programs for PC and mobile devices were developed to collect, transmit and check the results of measured data from applied sensors. The measurements obtained through each sensor are passed through the Wifi module to the management server and stored on the database server in real time. Analysis of the four-month measurement result values conducted in this study confirmed the stability and applicability of ICT technology application to LID facilities. Real-time measured values are found to be able to utilize big data to evaluate the functions of LID facilities and derive maintenance measures.

Simultaneous Analysis of Multi-Residual Pesticides Using UPLC (UPLC를 이용한 잔류농약 다성분 동시분석 연구)

  • Kim, Ki-Yu;Eom, Mi-Na;Kang, Jung-Bok;Do, Young-Suk;Moon, Su-Gyeong;Jung, Il-Hyeong;Son, Jong-Sung;Pi, Il-Seon;Park, Eun-Mi;Kim, Young-Su;Lee, Seong-Bong;Cho, Sang-Hun;Moon, Sun-Ae
    • Bulletin of Food Technology
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    • v.21 no.2
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    • pp.49-54
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    • 2008
  • 농산물 중 잔류농약을 보다 쉽고 효율적으로 분석 할 수 있는 다성분 동시분석 방법에 따라서 UPLC-PDA을 이용하여 기기조건에 따른 검출한계 및 정량한계를 식품별 최저 MRL과 비교하여 유효성을 알아보고 회수율을 통하여 방법의 재현성을 조사한 결과 다음과 같다. 41종의 농약에 대한 검량선은 직선성이 우수하였으며 검출한계 $0.005{\sim}0.109mg/kg$으로 나타났으며 정량한계 는 $0.018{\sim}0.363ppm$으로 나타났다. Cycloprothrin 등의 경우처럼 검출기의 감응도가 최저 MRL 기준을 초과하는 농약에 대한 보완으로는 검출감도가보다 우수한 UV 검출기 등의 병행 활용이 필요하다. 회수율에 따른 재현성은 쌀의 경우 첨가 농도 0.4 mg/kg 일때 $62.09{\sim}99.58%$로 편차범위는 $1.03{\sim}13.92%$ 얻을 수 있었다.

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