• 한국대기환경학회지
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• 제33권2호
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• pp.87-96
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• 2017

In this study, 4 gases containing typical chlorinated volatile organic compounds (VOCs) were treated by ultraviolet (UV) irradiation. The typical chlorinated VOCs are dichloromethane (DCM), trichloromethane (TCM), carbon tetrachloride (CTC) and trichloroethylene (TCE). The removal efficiency (RE) and the products of chlorinated VOCs by UV irradiation are investigated. At this time, 2 types of background gas (air and nitrogen) were used to figure out the RE by photooxidation and photolysis. The specification of UV-lamp used in this study was low-pressure mercury lamp emitting wavelength of 185~254 nm. The experimental conditions were set as initial VOC concentration of $180{\pm}10ppm$, empty bed retention time (EBRT) of 53 s, temperature of $23{\pm}2^{\circ}C$ and relative humidity of $65{\pm}5%$. In the photolysis condition with nitrogen ($N_2$) as background gas, the averaged RE of the 4 types of chlorinated VOCs was about 24% higher than that with photooxidation; and the REs of VOCs except CTC were confirmed as >99%. The composition of off-gases after UV photooxidation in air was investigated and several intermediates from DCM, TCM and TCE were detected by GC/MS. Among them, phosgene which is a toxics was detected as an intermediate of TCM. In addition, the concentration of carbon dioxide ($CO_2$) in the off-gases was measured to calculate the mineralization rate (MR). With the photooxidation, TCE showed the highest RE (>99%) while MR was the lowest (17%); and the MR of DCM was the highest (86%). In addition, particulate matters (PM) in the off-gases was also detected and high concentrated $PM_{10}$ ($21,580{\mu}g{\cdot}m^{-3}$) and $PM_{2.5}$ ($6,346{\mu}g{\cdot}m^{-3}$) were detected in TCE off-gas. More than 99% of the chlorinated VOCs could be removed using UV254-185 nm lamp, while it is necessary to conduct further studies on the production and treatment of secondary pollutants.

• 지역연구
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• 제15권2호
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• pp.131-153
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• 1999

Since 1980's there have been two trends that obviously developed in the would -- economics globalization and urban internationalization. China, with is reform and opening-up policy and rapid economic growth, keeps pace with these two trends. The term "International City" has no putative standard or definition. If we make an analogue of urban functional hierarchy in the world with a pyramid, the International Citiesa are the few elites on its top. The highest level international cities can be called "World City" or "Global City". In today's new international division of labor, they are diversified leading cities with control capacity on a world scale, like New York, London, and Tokyo. The secondary international cities are either diversified cities with influence and regulative functions on multinational scale or specialized cities on politics, economics, culture, or other aspects with worldwide impact. Judged by different criteria, there is no city that is qualified as International City with the exception of Hong Kong, which was returned to the P.R. of China in 1997. Nevertheless, Some favorable conditions for the development of the international city still exist in China. This country is already the sixth largest economic entity in the world, and the second largest economic entity in the world, and the second largest one if GNP estimated by ppp. Furthermore its import and export value make up for 40% of its GNP, indicating that China is repidly merging into global economy. In this 1, 2 billion-population country, the difference of economic levels between urban and rural, coastal and inland regions is so big that a few metropolises in the coastal region have the possibilities and potentials to develop into international cities regardless of rather low GNP per capita of the whole country. This article will focus on analysis from several perspectives, such as the proportion of foreign trade values in GDP, the proportion of imports and exports by foreign funded enterprises in total foreign trade value; distribution of the 500 largest foreign-funded enterprises; distribution of the 500 enterprises with largest import and export values; distrigbution of foreign computer and telecom companies with offices in China; the number of outward flights per week and the international tourists; the value of foreign capital used in cities and so on. From this analysis, it is predicted that Chinese international cities will surely emergy from the eastern coastal regions and they must be the core cities of metropolitan interlocking regions that have been formed or in the process of forming. Those international cities will arise from south to north in turn : Hong Kong-Guangzhu, Shanghai, Beijing-Tianjin, and perhaps the last one is Dalian-Shenyang. The other side of this issue is that there is a long way for the coming international cities in China except Hong Kong. At least China and these core cities must continually devote to (1) improve the regional composition of foreign capital sources. (2) improve the composition of export commodities. (3) improve the investment environment (including hard and soft environment) to attract more transnational corporations to settle. (4) deepen the reform of state-owned enterprises and establish Chinese own transnational corporations to enter the world market.ons to enter the world market.

• The Korean Journal of Physiology and Pharmacology
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• 제19권5호
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• pp.389-399
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• 2015

Zinc has been considered as a vital constituent of proteins, including enzymes. Mobile reactive zinc ($Zn^{2+}$) is the key form of zinc involved in signal transductions, which are mainly driven by its binding to proteins or the release of zinc from proteins, possibly via a redox switch. There has been growing evidence of zinc's critical role in cell signaling, due to its flexible coordination geometry and rapid shifts in protein conformation to perform biological reactions. The importance and complexity of $Zn^{2+}$ activity has been presumed to parallel the degree of calcium's participation in cellular processes. Whole body and cellular $Zn^{2+}$ levels are largely regulated by metallothioneins (MTs), $Zn^{2+}$ importers (ZIPs), and $Zn^{2+}$ transporters (ZnTs). Numerous proteins involved in signaling pathways, mitochondrial metabolism, and ion channels that play a pivotal role in controlling cardiac contractility are common targets of $Zn^{2+}$. However, these regulatory actions of $Zn^{2+}$ are not limited to the function of the heart, but also extend to numerous other organ systems, such as the central nervous system, immune system, cardiovascular tissue, and secretory glands, such as the pancreas, prostate, and mammary glands. In this review, the regulation of cellular $Zn^{2+}$ levels, $Zn^{2+}$-mediated signal transduction, impacts of $Zn^{2+}$ on ion channels and mitochondrial metabolism, and finally, the implications of $Zn^{2+}$ in health and disease development were outlined to help widen the current understanding of the versatile and complex roles of $Zn^{2+}$.

• Imaging Science in Dentistry
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• 제48권1호
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• pp.11-19
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• 2018

Purpose: This study compared the diagnostic accuracy of cone-beam computed tomography (CBCT) scans obtained with 2 CBCT systems with high- and low-resolution modes for the detection of root perforations in endodontically treated mandibular molars. Materials and Methods: The root canals of 72 mandibular molars were cleaned and shaped. Perforations measuring 0.2, 0.3, and 0.4 mm in diameter were created at the furcation area of 48 roots, simulating strip perforations, or on the external surfaces of 48 roots, simulating root perforations. Forty-eight roots remained intact(control group). The roots were filled using gutta-percha (Gapadent, Tianjin, China) and AH26 sealer (Dentsply Maillefer, Ballaigues, Switzerland). The CBCT scans were obtained using the NewTom 3G (QR srl, Verona, Italy) and Cranex 3D (Soredex, Helsinki, Finland) CBCT systems in high- and low-resolution modes, and were evaluated by 2 observers. The chi-square test was used to assess the nominal variables. Results: In strip perforations, the accuracies of low- and high-resolution modes were 75% and 83% for NewTom 3G and 67% and 69% for Cranex 3D. In root perforations, the accuracies of low- and high-resolution modes were 79% and 83% for NewTom 3G and was 56% and 73% for Cranex 3D. Conclusion: The accuracy of the 2 CBCT systems was different for the detection of strip and root perforations. The Cranex 3D had non-significantly higher accuracy than the NewTom 3G. In both scanners, the high-resolution mode yielded significantly higher accuracy than the low-resolution mode. The diagnostic accuracy of CBCT scans was not affected by the perforation diameter.

• 한국지역지리학회지
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• 제14권5호
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• pp.492-506
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• 2008

본 연구에서는 중국 대련시(大連市)에 투자한 한국기업의 기업네트워크 특성을 분석하기 위해, 크게 원자재 및 부품조달과 제품판매, 그리고 이들 기업간의 협력관계를 사회문화와 제도적 특성에 초점을 두고 고찰하였다. 대련투자 한국기업들은 원자재 및 부품, 반제품 공급기업과의 관계에 있어서는 비국지적 네트워크가, 제품판매 즉 고객네트워크에서는 국지적 네트워크가 상대적으로 강하게 나타났다. 기업규모면에서는 대기업은 비국지적 네트워크가, 중소기업은 국지적 네트워크가 상대적으로 강한 특성을 보이고 있었다. 기업간 네트워크를 통한 협력은 공급기업과는 공동마케팅, 장비공동이용, 기술지원과 정보교환이 중심이고, 고객기업과는 공동마케팅과 인력훈련에 있어서 협력이 중심이었다. 특히 협력관계를 맺고 있는 고객기업의 대부분은 현지의 중국기업으로, 지역적으로 대련시(大連市) 지역을 포함한 중국의 북경, 상해, 광주, 천진 등 중국 전역에 걸쳐 광범한 고객네트워크를 구축하고 있다. 지역별 협력관계를 보면, 대련시(大連市) 지역의 기업과는 주로 공동제품개발, 금융과 인력훈련이, 대련시(大連市) 이 외 기업과는 마케팅 협력, 기술지원 및 정보교환과 R&D가 중심이 되고 있다.

• Journal of Microbiology and Biotechnology
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• 제25권8호
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• pp.1195-1204
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• 2015

Increasing evidence suggests that gut microbiota underpin the development of health and longevity. However, our understanding of what influences the composition of this community of the longevous has not been adequately described. Therefore, illumina sequencing analysis was performed on the gut microbiota of centenarians (aged 100-108 years; RC) and younger elderlies (aged 85-99 years; RE) living in Bama County, Guangxi, China and the elderlies (aged 80-92 years; CE) living in Nanning City, Guangxi, China. In addition, their diet was monitored using a semiquantitative dietary questionary (FFQ 23). The results revealed the abundance of Roseburia and Escherichia was significantly greater, whereas that of Lactobacillus, Faecalibacterium, Parabacteroides, Butyricimonas, Coprococcus, Megamonas, Mitsuokella, Sutterella, and Akkermansia was significantly less in centenarians at the genus level. Both clustering analysis and UniFraq distance analysis showed structural segregation with age and diet among the three populations. Using partial least square discriminate analysis and redundancy analysis, we identified 33 and 34 operational taxonomic units (OTUs) as key OTUs that were significantly associated with age and diet, respectively. Age-related OTUs were characterized as Ruminococcaceae, Clostridiaceae, and Lachnospiraceae, and the former two were increased in the centenarians; diet-related OTUs were classified as Bacteroidales, Lachnospiraceae, and Ruminococcaceae. The former two were deceased, whereas the later one was increased, in the high-fiber diet. The age and high-fiber diet were concomitant with changes in the gut microbiota of centenarians, suggesting that age and high-fiber diet can establish a new structurally balanced architecture of gut microbiota that may benefit the health of centenarians.

• Journal of Animal Science and Technology
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• 제52권4호
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• pp.287-296
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• 2010

본 시험은 발효미역부산물의 수준별 첨가가 Holstein 비유우의 산유량과 유성분, 혈중 호르몬과 대사산물 및 IgG와 IgA의 농도에 미치는 영향을 조사하여 발효미역부산물의 사료적 가치를 평가하기 위하여 실시하였다. 산유량을 보면 시험 60일에서 대조구와 1% FBSW, 2% FBSW가 각각 28.99 kg/d, 31.00 kg/d, 30.39 kg/d로 1% FBSW구에서 대조구에 비하여 2 kg/d의 유량증가를 보였으며, D0에 대한 유량 증가 또한 대조구 -1.84 kg/d에 비하여 1% FBSW는 0.23 kg/d로 유의성 있는 증가를 보였다(P<0.05). 유지방, 유단백, SNF, MUN 등 유성분에서는 처리간에 유사한 결과를 나타냈다. 우유중의 Ca농도는 시험 40일에서 대조구가 13.73 mg/dl, 1% FBSW가 18.02 mg/dl, 16.64 mg/dl로 통계적인 유의차를 나타냈다(p<0.05). 우유 중 total cholesterol은 시험개시와 시험 종료시 대조구와 유사한 결과를 나타냈다. 우유중의 체세포는 시험 60일에서 13.86~15.66만개/ml 범위내(체세포 1등급기준 < 20만개/ml)에 있음이 관찰되어 발효미역부산물 첨가의 효과가 관찰되지 않았다. 혈중 IgG는 시험 종료 시 처리구간 유사하게 나타났으며 IgA의 농도는 대조구, 1% FBSW, 2% FBSW가 각각 181.23, 207.83, 242.39 ${\mu}g$/ml로 발효미역부산물 첨가구에서 대조구에 비해 높게 나타났으나 통계적인 유의차는 없었다. 갑상선호르몬인 T4는 1%, 2% 발효미역부산물 첨가에 의해 뚜렷한 증가를 보였고(p<0.05), 비유촉진 호르몬인 prolactin 역시 통계적 유의성 차이는 없었으나 1% FBSW가 0.76ng/ml로 가장 높게 나타났다. 혈중 대사산물인 glucose는 처리간 유의차는 나타나지 않았으며 NEFA의 경우도 0.30~0.32 mEq/dl로 처리간 동일한 수준으로 나타냈다. BUN의 경우 처리 40일에서 대조구, 1% FBSW, 2% FBSW가 각각 19.22, 17.81, 16.58 mg/dl로 2% FBSW가 유의적으로 낮게 나타났으나, 다른 비유기에는 유의성 있는 차이를 보이지 않았다. 혈중 WBC, RBC, Hb, Hct, T-B, ALP, GOT, GPT 등 항목의 측정결과 시험 20일에서는 각 항목에서 처리별 차이가 나타나지 않았으며 시험 40일의 경우 혈중 GOT가 1% FBSW이 107.71 IU/L로 가장 낮게 나타났고 2% FBSW가 146.71 IU/L, 대조구가 163.57 IU/L로 통계적인 유의차를 나타냈으나(p<0.05), 다른 비유기에는 유의차를 보이지 않았다. 결과를 종합해 볼 때 1% 수준의 발효미역부산물의 첨가는 젖소의 산유량 증가에 효과적이며, 이는 비유관련 호르몬의 발현을 증가시킴으로 기인된 것으로 판단된다. 아울러 우유중 Ca의 함량이 현저히 증가되는 결과를 볼 때 발효미역부산물을 보다 효율적으로 이용한다면 고능력 및 고기능성 젖소사료로의 이용가능성이 높을 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.3773-3777
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• 2015

Background: This study aimed to establish a nomogram by combining clinicopathologic factors with overall survival of stage IA-IIB cervical cancer patients after complete resection with pelvic lymphadenectomy. Materials and Methods: This nomogram was based on a retrospective study on 1,563 stage IA-IIB cervical cancer patients who underwent complete resection and lymphadenectomy from 2002 to 2008. The nomogram was constructed based on multivariate analysis using Cox proportional hazard regression. The accuracy and discriminative ability of the nomogram were measured by concordance index (C-index) and calibration curve. Results: Multivariate analysis identified lymph node metastasis (LNM), lymph-vascular space invasion (LVSI), stromal invasion, parametrial invasion, tumor diameter and histology as independent prognostic factors associated with cervical cancer survival. These factors were selected for construction of the nomogram. The C-index of the nomogram was 0.71 (95% CI, 0.65 to 0.77), and calibration of the nomogram showed good agreement between the 5-year predicted survival and the actual observation. Conclusions: We developed a nomogram predicting 5-year overall survival of surgically treated stage IA-IIB cervical cancer patients. More comprehensive information that is provided by this nomogram could provide further insight into personalized therapy selection.

• Asian-Australasian Journal of Animal Sciences
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• 제29권4호
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• pp.500-508
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• 2016

This study was conducted to investigate the effects of Momordica charantia saponin (MCS) on ruminal fermentation of maize stover and abundance of selected microbial populations in vitro. Five levels of MCS supplements (0, 0.01, 0.06, 0.30, 0.60 mg/mL) were tested. The pH, $NH_3-N$, and volatile fatty acid were measured at 6, 24, 48 h of in vitro mixed incubation fluids, whilst the selected microbial populations were determined at 6 and 24 h. The high dose of MCS increased the initial fractional rate of degradation at t-value = 0 ($FRD_0$) and the fractional rate of gas production (k), but decreased the theoretical maximum of gas production ($V_F$) and the half-life ($t_{0.5}$) compared with the control. The $NH_3-N$ concentration reached the lowest concentration with 0.01 mg MCS/mL at 6 h. The MSC inclusion increased (p<0.001) the molar proportion of butyrate, isovalerate at 24 h and 48 h, and the molar proportion of acetate at 24 h, but then decreased (p<0.05) them at 48 h. The molar proportion of valerate was increased (p<0.05) at 24 h. The acetate to propionate ratio (A/P; linear, p<0.01) was increased at 24 h, but reached the least value at the level of 0.30 mg/mL MCS. The MCS inclusion decreased (p<0.05) the molar proportion of propionate at 24 h and then increased it at 48 h. The concentration of total volatile fatty acid was decreased (p<0.001) at 24 h, but reached the greatest concentration at the level of 0.01 mg/mL and the least concentration at the level of 0.60 mg/mL. The relative abundance of Ruminococcus albus was increased at 6 h and 24 h, and the relative abundance of Fibrobacter succinogenes was the lowest (p<0.05) at 0.60 mg/mL at 6 h and 24 h. The relative abundance of Butyrivibrio fibrisolvens and fungus reached the greatest value (p<0.05) at low doses of MCS inclusion and the least value (p<0.05) at 0.60 mg/mL at 24 h. The present results demonstrates that a high level of MCS quickly inhibits in vitro fermentation of maize stover, while MCS at low doses has the ability to modulate the ruminal fermentation pattern by regulating the number of functional rumen microbes including cellulolytic bacteria and fungi populations, and may have potential as a feed additive applied in the diets of ruminants.

• Journal of Animal Science and Technology
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• 제53권4호
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• pp.349-356
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• 2011

DS-01 균주 접종에 의한 미역부산물 발효산물이 분해 정도, 영양소 변화 및 미생물오염 정도에 관한 관찰과 반추위 발효성상에 미치는 영향을 관찰하여 미역부산물의 저장성 확보와 반추동물의 사료로서의 이용가능성을 발효단계에 따라 조사하였다. DS-01 균주와 함께 배양된 미역부산물은 발효 1개월부터 현저한 분해율을 보이기 시작했다. 미역부산물중의 영양성분 함량은 발효와 함께 커다란 변화를 나타내지 않았으며 모든 처리에서 반추동물에 병원성을 가지는 미생물은 검출되지 않았다. In vitro 실험에서는 발효시간 및 첨가농도에 따른 pH 변화, 암모니아태 질소와 휘발성지방산의 생성에 대한 영향을 조사하였다. pH의 경우 6% FBSW는 1개월 및 2개월 발효조건에서 대조구, 2% 및 4% FBSW 보다 pH 값이 증가한 것을 나타내었다. 암모니아태 질소의 생성에 미치는 영향을 보면 1개월 FBSW 경우 실험 3시간 경과 후가 대조구에 비해 높은 농도를 나타내었지만 시간이 경과에 따라 대조구보다 감소한 경향을 보인다. 2개월 FBSW의 경우 4% 첨가량만 24시간 경과 후 타 처리구에 비해 높은 농도를 나타내었다. 특히, 전 발효기간 동안 6% FBSW 처리구가 발효 3시간과 24시간 경과 후 타 처리구에 비하여 낮게 나타나는 경향을 보였다. 휘발성지방산의 경우 발효 1개월 미역부산물의 4, 6% FBSW 첨가구가 6시간 경과 후 총 VFA의 농도가 현저하게 증가하는 양상을 나타내었고(p<0.05), 발효 2개월 미역부산물의 2, 4% FBSW 첨가구가 9시간 경과 후 총 VFA 농도가 6% FBSW 첨가구에 비해 현저하게 증가하는 양상을 나타냈다(p<0.05).