Earticle

본 연구는 토양유실량 산정을 위해 사용되는 USLE P factor 선정의 문제점 확인 및 개선방향 제시에 대한 연구이다. USLE P factor는 경작지를 어떻게 관리하여 사용하느냐에 따라 그 값이 달라지는 계수이다. 하지만 기존 연구들은 경작지 상황에 따른 선정이 아닌 유역의 경사도에 대한 P factor를 선정함에 따라 토양유실량이 과다 산정되는 경향이 있다. 뿐만 아니라 처음에 이 식은 제안한 Wishmeier와 Smith에 의해 정의된 다양한 조건들에 부합되지 않게 인자를 선정하고 있어 토양유실 량 산정에 대한 정확성이 떨어지고 있다. 이에 환경부에서는 이러한 문제점을 해결하기 위해 표토관련고시를 제정하고 이에 따른 P factor를 선정하도록 제안하고 있다. 하지만 미국에서 제안된 조건을 그대로 국내 사정에 적용하도록 되어 있어 많은 문제점을 야기하고 있다. 이에 본 연구에서는 실제 토양유실이 심각하게 이루어지고 있는 유역(양구 해안면 유역, 홍천 내면 자운리 유역, 안동 임하면 반변천 상류유역)을 선정하여 경사장과 경사도를 측정하고 각 필지에 적용된 관리방법과 경운방법 을 조사하여 각 조건들에 적용한 후 고시에 의거하여 제시된 조건을 통해 선정된 인자와의 비교를 통해 고시의 문제점을 확 인하였고, 문헌연구를 통한 새로운 조건에 대입하여 새로운 인자들을 선정하였다. 연구 결과, 환경부에서 제시한 표토관련고 시에 의거하여 선정된 P factor의 경우 대상 유역 3곳에서 0.8~1.0사이의 값을 제시하고 있었다. 하지만 처음 제안된 조건들 을 대입하여 P factor를 선정해본 결과 각 경사도 및 경사장 조건에 부합하여 선정된 값은 고시를 통해 선정된 값과는 차이 가 있음을 확인하였다. 이를 통해 국내 환경에 적합한 P factor를 선정하기 위한 조건을 개발하기 위한 연구가 지속적으로 이루어져야 한다고 판단된다.

The USLE P factor is a factor that varies depending on how croplands are managed and cultivated. Previous studies tend to overestimate the amount of soil loss because the factor was estimated from the slope of the watershed rather than the estimate of each cultivated land. In addition, the accuracy of estimating the soil loss is decreasing due to the fact that the factor is calculated without considering various conditions of cultivated land defined by Wishmeier and Smith. In order to overcome these problems, the Ministry of Environment (MOE) has proposed to establish the topsoil notification and calculate the P factor according to the cultivation methods (e.g., tillage system, support practice). However, it is required to apply the conditions proposed in the United States to domestic circumstances as it is causing uncertainties. Thus, this study selected the watersheds where soil loss was serious (Haean, Jaun, Banbyeoncheon), measured the actual slopes and slope lengths, and examined the crop, tillage systems, and support practice for each cultivated land. The P factors were recalculated considering the actual conditions of cultivated land and compared to the factors proposed by the previous studies (MOE). As the result of the study, the P factors calculated based on the previous studies were 0.8 ~ 1.0 in three watersheds. On the other hand, it is confirmed that there is a significant difference between the factors notified by MOE and estimated by reflecting the topography and cultivation methods in this study. Therefore, it is considered that the research for developing the cultivation conditions to calculate the P factor suitable for the domestic environment should be continuously carried out.

In this study, we investigated the effects of the flavonoid galangin on the expression of the mucin 5AC (MUC5AC) gene in airway cells. Human pulmonary epithelial NCI-H292 cells were pretreated with galangin for 30 min and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 h. We also examined the effects of galangin on the PMA-induced nuclear factor-κB (NF-κB) signaling pathway. Galangin inhibited the production of glycoproteins and the expression of MUC5AC mRNA induced by PMA via prevention of NF-κB inhibitor α degradation and NF-κB p65 nuclear translocation. These findings indicated that galangin suppressed mucin gene expression by modulating the NF-κB signaling pathway in human pulmonary epithelial cells.

The purpose of this study was to investigate the modification of expression and functionality of the drug transporter P-glycoprotein (P-gp) by tumor necrosis factor-alpha (TNF-${\alpha}$) and interferon-gamma (IFN-${\gamma}$) at the blood-brain barrier (BBB). We used immortalized human brain microvessel endothelial cells (iHBMEC) and primary human brain microvessel endothelial cells (pHBMEC) as in vitro BBB model. To investigate the change of p-gp expression, we carried out real time PCR analysis and Western blotting. To test the change of p-gp activity, we performed rhodamin123 (Rh123) accumulation study in the cells. In results of real time PCR analysis, the P-gp mRNA expression was increased by TNF-${\alpha}$ or IFN-${\gamma}$ treatment for 24 hr in both cell types. However, 48 hr treatment of TNF-${\alpha}$ or IFN-${\gamma}$ did not affect P-gp mRNA expression. In addition, co-treatment of TNF-${\alpha}$ and IFN-${\gamma}$ markedly increased the P-gp mRNA expression in both cells. TNF-${\alpha}$ or IFN-${\gamma}$ did not influence P-gp protein expression whatever the concentration of cytokines or duration of treatment in both cells. However, P-gp expression was increased after treatments of both cytokines together in iHBMEC cells only compared with untreated control. Furthermore, in both cell lines, TNF-${\alpha}$ or IFN-${\gamma}$ induced significant decrease of P-gp activity for 24 hr treatment. And, both cytokines combination treatment also decreased significantly P-gp activity. These results suggest that P-gp expression and function at the BBB is modulated by TNF-${\alpha}$ or/and IFN-${\gamma}$. Therefore, the distribution of P-gp depending drugs in the central nervous system can be modulated by neurological inflammatory diseases.

이전 연구들에서 rutin과 quercetin을 포함한 여러 flavonoids의 암예방 활성이 보고되었으나, rutin의 경우 섭취 시 체내에서 HVA, HPAA, DHT라는 대사체로 변형되어 흡수된다. 그러나, 이들 대사체와 관련한 암예방 효능 및 그 분자생물학적 작용기작에 대한 연구 결과는 보고된 바가 없어, 본 연구에서 이를 규명하였다. DHT는 EGF로 유도된 세포 변형을 억제하였으며, AP-1 전사인자의 활성 또한 억제하였다. DHT는 Raf-1 효소 활성을 효과적으로 저해하므로서 MEK 및 ERK의 인산화를 억제하였으며, Raf-1과 ATP는 비경쟁적으로 직접 결합하여 Raf-1 효소 활성을 저해한다는 사실을 밝혀내었다. 이와는 대조적으로, rutin은 EGF로 유도된 세포 변형, AP-1 활성, ERK 신호전달체계, Raf-1 효소 활성을 억제하지 못하였다. 이상의 연구결과는 DHT의 암예방 활성이 발암과정과 밀접한 연관이 있는 Raf-1 효소 활성을 억제하여 세포 변형을 억제하는 것과 관련되어 있다는 것을 제시한다.

In summary, the rutin metabolite DHT significantly reduced EGF-induced neoplastic transformation in JB6 P+ cells. This inhibition was mediated mainly by blocking the Raf/MEK/ERK signaling pathway and subsequent suppression of AP-1 activities. DHT attenuated Raf-1 kinase activity by directly binding to Raf-1 in vitro and ex vivo. Taken together, these results suggest that Raf-1 may be a critical molecular target to suppress DHT-induced neoplastic transformation, which is mainly attributable to the chemopreventive potential of several foods containing rutin.

Universal soil loss equation (USLE) had been employed to estimate potential soil loss since it was developed from the statewide data measured and collected in the United States. The equation had an origin in average annual soil loss estimation though, it was modified or improved to provide better opportunities of soil loss estimation outside the United States. The equation has five factors, most studies modifying them to adapt regional status were focused on rainfall erosivity factor and cover management factor. While the conservation practice factor (USLE P factor) is to represent distinct features in agricultural fields, it is challenging to find studies regarding the factor improvements. Moreover, the factor is typically defined using slopes. The factor defining approach was suggested in the study, the approach is a step-by-step method allowing USLE P factor definition with given condition. The minimum condition is slope and field location to provide an opportunity for using in any GIS software and to reflect regionally distinct features. If watershed location, slope, crop type, and mulching type on furrows are given, detailed definition of the factors are possible. The approach was developed from field survey in South-Korea, it is expected to be used for potential soil loss using USLE in South-Korea.

손상 또는 균열된 구조물의 내구성을 향상시키려는 과제는 연구자들과 엔지니어들에게 중요한 과제로 떠오르고 있다. 팻취로 보강되지 않은 균열판과 팻취보강된 균열판의 응력확대계수 및 응력등고선의 산정 및 비교에 의한 균열선단에서의 파괴거동의 특성을 적분형 르장드르 다항식에 기초를 둔 계층적 무강성요소를 사용하여 표현하고자 한다. 이 연구에서는 등가단층이론이 채택되므로, 제안된 무강성요소는 불연속 균열부를 강성이 0인 연속체로 간주된다. 그러므로 균열을 모델링하는 무강성요소의 변장비는 매우 커질 수밖에 없다. 제안된 요소의 강건성을 보이기 위해 형상비 변화에 따른 에너지방출률, 변위 및 응력값에 대한 유한요소해의 민감도는 변장비를 2000까지 증가시켜 가면서 평가되었다. 한편, 강성도미분법과 변위외삽법이 인장모우드가 발생되는 문제의 응력확대계수를 예측하는데 사용된다. 제안된 계층적 무강성요소는 팻취보강된 균열문제를 해석할 수 있는 대안중의 하나라 평가된다.

The enhancement of the service life of damaged or cracked structures is a major issue for researchers and engineers. The hierarchic void element based on the integrals of Legendre polynomials is used to characterize the fracture behaviour of unpatched crack as well as repaired crack with bonded composite patches by computing the stress intensity factors and stress contours at the crack tip. Since the equivalent single layer approach is adopted in this study, the proposed element is necessary to represent a discontinuous crack part as a continuum body with zero stiffness. Thus the aspect ratio of this element to represent the crack should be extremely slender. The sensitivity of numerical solution with respect to energy release rate, displacement and stress has been tested to show the robustness of zero stiffness element as the aspect ratio is increased up to 2000. The stiffness derivative method and displacement extrapolation method have been applied to calculate the stress intensity factors of Mode I problem. It is noted that the proposed hierarchical void element can be one of alternatives to analyze the patched crack problems.

중소기업의 건전한 성장은 중국의 안정적인 경제성장에 탄탄한 토대를 마련해주고 있으며 신규고용의 창출에도 일조를 하고 있다. 그러나 중 소기업은 작은 규모, 낮은 재무안전성 및 위기관리능력의 부족으로 인해 높은 금융리스크와 비용에 노출되어 있어 전통적인 금융기관으로부터 자금조달을 받기 어렵다. 온라인 P2P대출은 인터넷 기술과 민간 대출이 결합한 새로운 금융 패러다임이다. 특히 중국의 경우, 전통적인 자본시장의 발달이 상대적으로 더딘 상황에서 P2P대출 플랫폼의 등장 이후 중소기업의 자금조달 통로로서의 역할을 충실히 수행하고 있다. 본 논문에서는 소형기업 차입자의 차입성공에 영향을 미치는 요인을 분석하여 P2P대출 플랫폼에서 투자자가 중요하게 여기는 요인을 확인하고자 한다. 본 연구에서는 P2P대출 차입성공여부에 영향을 미치는 요인을 기업특성, 차입특성, 차입자특성 및 P2P인증속성으로 구분하여 살펴보았다. 분석결과를 요약하면 다음과 같다. 중국 P2P대출 플랫폼에서 기업규모는 클수록, 차입금액은 상대적으로 적을수록, 차입이자율은 높게 제시할 수록, 신용등급은 높을수록, 여성이고 연체기록이 없으며 기관담보인증일 때 차입성공률은 높아진다. 이러한 결과는 온라인 P2P대출은 효율적 이지만 차입자에 대한 평가는 오프라인 대출과 크게 다르지 않다는 것을 시사한다.

Small andmicro enterprises is supporting China's transformation of economic growthmode, themain driving force to promote sound and rapid development of the entity economy, and for the sustained and stable economic growth and lay a solid foundation, but also for new employment provide a lot of job however. But because of small and micro enterprises by small scale and few assets, anti risk ability is weak, coupled with the financial system is not perfect, the corporate governance mechanism imperfect decided the financing risk, high cost, it is difficult to get traditional financial institutions funding support. Online P2P lending is a new finance paradigm which combines internet technology and private lending. In particular, in China, where the development of traditional capital markets has been relatively slow, online P2P lending is faithfully serving as a means of financing for small-to-mid sized companies since the emergence of P2P lending platforms. The present study attempts to identify the factors considered important by investors on P2P lending platforms by analyzing the factors that impact the lending success of Chinese small and micro enterprises. The present study divided factors impacting the lending success of P2P loans into company characteristics, lending characteristics, borrower characteristics, and P2P certification properties with the purpose of examination. The analysis results are summarized as follows. Lending success ratios for Chinese P2P lending platforms are higher when the size of the company is bigger, the loan is relatively smaller, the borrowing rate of interest is greater, the credit rating is higher, the borrower is a woman and has no record of overdue payments, and the lending involves institution certification. Such a result implies that although P2P loans are efficient, the appraisal of the borrower is not largely different fromoffline loans.

At the center of the repeating evolution of IT industry, there is mobile computing in the ubiquitous environment, and the increasing usage of smart phones contribute more to its growth. P corporation co-developed with Google and implemented smart work system called SWP for the purpose of ‘communication and collaboration with co-workers' beyond the general goal of increasing productivity and comfort of employees. The primary objective of this study is to objectively analyze the influence of the effect factor from end user's perspective and user satisfaction on SWP usage, intention for continuous usage and individual performance. To accomplish this research purpose, this study established research models and hypothesis by collective review about information system success models, and tested the research hypotheses using the structural equation modeling technique by data collected from 320 SWP system users of P corporation. Variations for system satisfaction evaluation standard are 1)SW system usage 2) intention for continuous usage 3) individual performance, effect variations are 1) social factors 2) technical factors 3) combination of social and technical factors. Therefore, this study is about influence factors on success of SWP system and how the factors impact the outcome. The test results of this research model is summarized as follows. Firstly, system user's satisfaction had positive impact on all three; SWP system usage, intention for continuous usage and individual performance. Secondly, social factor ‘SWP control system' and technical factor ‘information quality' and ‘system quality' had positive impact on SWP system user satisfaction, while social factor ‘shared value' and technical factor ‘service quality' did not have significant effect on user satisfaction. Shared value however, had interactive effect with ‘information quality' and ‘service quality'. This study is expected to contribute to spread of academic research on smart work system by suggesting a model that can show important factors for corporation while explaining the successful implementation of SWP and its continuous usage.

HPGe 검출기를 이용하여 밀도가 다양한 환경시료에 대한 정밀 분석시 정확한 분석을 위해서는 밀도보정인자가 필요하다. 밀도에 대한 보정인자를 구하기 위해서 본 연구에서는 몬테카를로 코드인 MCNPX 코드를 사용하여 크리스털의 높이, 지름및 코어의 크기와 같은 특성이 다른 세 대의 p-type HPGe 검출기를 모사하고 밀도 1 g/cm3의 교정용 표준시료를 이용하여 모델링을 검증하였다. 검증을 통하여 모델링을 확정한 후 0.3, 0.6, 0.9, 1.0, 1.2, 1.5 g/cm3 밀도를 가진 샘플에 대한 효율을 시뮬레이션하고 밀도보정인자를 도출하였다. 도출된 각 검출기에 대한 밀도보정인자를 비교하였을 때 전 에너지 범위에서 그차이가 거의 없음을 확인하였으며 이는 검출기의 크리스털과 같은 주요 특성에 대해 밀도보정인자가 독립적임을 의미한다.

The precise determination of the activity for each radionuclide in environmental samples requires the self-absorption correction factor. In this research, we derived the self-absorption correction factor for three p-type high purity germanium detectors using the Monte Carlo code MCNPX. These detectors have different characteristics such as crystal diameter, height and size of the core. We compared the calculated full-energy peak efficiency with the experimental value using a standard sample with 1 g/cm3 density and verified the modeling. We simulated the dependency of the full-energy peak efficiency on the 0.3, 0.6, 0.9, 1.0, 1.2 and 1.5 g/cm3 samples and obtained the corresponding self-absorption correction factor. The self-absorption correction factors calculated for the three detectors differ by less than 1% over most of the energy range and sample densities considered. This indicates that the self-absorption correction factors are independent of the crystal characteristics of HPGe detector.

현대 인류는 비약적인 경제성장으로 인하여 급격한 도시화와 산업화를 이루었다. 하지만 이러한 성장을 위해 수반되는 자원개발 및 생활환경조성으로 인한 토지개발이 진행되어 많은 양의 토양이 유실되고 있다. 토양유실을 관리하기 위해서는 모니터링을 통해 관리하는 방법과 모형을 통해 유실되는 토양의 양을 산정하여 관리방안을 제시하는 방법이 있다. 현재 전 세계적으로 사용되고 있는 범용토양유실량 산정공식(USLE)은 사용상의 편리성과 연간 토양유실량을 산정할 수 있는 이점이 있다. 뿐만 아니라 국내의 환경부에서는 USLE 공식을 적용한 '표토 침식 현황에 관한 고시'를 제정하여 유실되는 표토를 관리하고 있다. 하지만 USLE 공식을 구성하고 있는 인자 중 P factor는 경사도만을 고려하여 인자 값을 제시하고 있으며, 밭에 적용된 관리방법과 작물, 경운방법 등을 고려하지 않아 방법에 차이에 따른 발생되는 토양유실량에 차이가 발생하게 된다. 이러한 문제점을 고려하여 경작지의 경사도와 적용된 관리방안을 복합적으로 고려한 P factor 선정 체계가 필요한 시점이다. 따라서 본 연구에서는 실제 경작지 조사를 통해 경작지 별 관리방안과 경사도를 고려한 P factor를 제안하고자 한다. 관리방안과 경사도를 복합적으로 고려한 P factor를 제안하기 위해 선정된 유역은 강원도 양구군 해안면 유역과 자운리 유역, 안동시 임동면 반변천 상류 유역을 선정하여 위치하고 있는 밭에 대한 현장조사를 진행하였다. 조사항목은 경작지의 경사도, 재배작물, 관리방법, 경운방법 등을 조사하였으며, 이를 바탕으로 경사도와 관리방법을 복합적으로 고려한 P factor를 재산정 하였다. P factor를 재산정한 결과 대상 유역 내 밭에 적용된 관리방법과 경운방법, 재배작물의 차이로 인해 상이한 값이 산정되었다. 또한 기존 P factor와 재산정된 P factor를 사용하여 산정한 토양유실량의 차이가 약 17%정도 나타났다. 따라서 본 연구를 통해 재산정된 P factor는 토양유실에 직간접적으로 관여하는 조건들을 복합적으로 고려한 P factor로써 정확한 토양유실량을 산정하는데 기여할 것으로 판단되며, 본 연구를 바탕으로 전국단위 USLE P factor를 산정을 위한 추가적인 연구가 필요하다고 판단된다.

Background : Angiogenesis is one of the most important factors in the progression and metastasis of malignancies. Angiogenesis is a multistep process requiring the interaction of numerous factors able to stimulate the growth and development of new vessels. But, understanding of the mechanism involved in VEGF expression is unclear. Methods : Expressions of p53 and VEGF, and neovasculiarization were examined in 19 cases of surgically resected non-small cell carcinoma of the lung by the immunohistochemical staining. Furthermore, VEGF mRNA expressions were quantified in all cases using the real-time quantitative RT-PCR. These results were compared with clinicopathologic parameters such as histologic grade and stage. Results : Tumors with high aberrant p53 expressions showed significantly higher VEGF mRNA expressions and microvessel counts than those with low p53 expressions. Expressions of p53 as well as VEGF and micovessel counts were closely associated with the tumor stage, but not with the histologic grade and other clinical parameters. Conclusions : These results suggest that aberrant p53 expression may play a role in the regulation of VEGF expression and may be involved in controlling angiogenesis in non-small cell carcinoma of the lung.

본 연구에서 돼지 PBMC에 t10c12-CLA 처리는 TNF-${\alpha}$생산을 증가시켰으나, LPS 자극 PBMC에서는 TNF-${\alpha}$생산을 감소시켰다. t10c12-CLA 처리는 PBMC의 inhibitory ${\kappa}B$ ($I{\kappa}B$)-${\alpha}$ 단백질 분해를 증가시키고 NF-${\kappa}B$ p65 활성 수준을 증가시켰다. 그러나 LPS 자극 PBMC에서는 상반되는 효과가 관찰되었다. 특히, LPS 비자극 PBMC에서 t10c12-CLA는 NF-${\kappa}B$ 저해제인 caffeic acid phenethyl ester (CAPE)를 처리한 경우 NF-${\kappa}B$ p65 활성 수준을 증가시켰으나 반대로 LPS로 자극한 CAPE 처리 PBMC에서는 NF-${\kappa}B$ p65 활성 수준을 억제시켰다. 이상의 결과는 t10c12-CLA가 돼지 PBMC에 있어 LPS 자극 유무에 따라 다른 효과를 가질 수 있으며, 이는 NF-${\kappa}B$ p65 활성도의 변화와 관련성이 있음을 보여주고 있다.

Nuclear factor ${\kappa}B$ (NF-${\kappa}B$) is a nuclear transcription factor that modulates the expression of inflammatory cytokines such as tumor necrosis factor (TNF)-${\alpha}$. trans-10, cis-12 (t10c12)-conjugated linoleic acid (CLA) participates in the inhibition of TNF-${\alpha}$ production upon lipopolysaccharide (LPS)-stimulation. However, in our previous study, t10c12-CLA enhanced the production of TNF-${\alpha}$ by LPS-unstimulated porcine peripheral blood mononuclear cells (PBMCs) and RAW 264.7 macrophages in vitro. To resolve this apparent contradiction, we hypothesized that the effect of t10c12-CLA on TNF-${\alpha}$ production depends on NF-${\kappa}B$ activation induced by LPS stimulation. To test this hypothesis, we assessed the in vitro effect of t10c12-CLA on TNF-${\alpha}$ production and NF-${\kappa}B$ p65 activity in LPS-stimulated and LPS-unstimulated porcine PBMCs. t10c12-CLA treatment resulted in increased TNF-${\alpha}$ production by LPS-unstimulated PBMCs but decreased TNF-${\alpha}$ production by LPS-stimulated PBMCs. t10c12-CLA increased the degradation of inhibitory ${\kappa}B$ ($I{\kappa}B$)-${\alpha}$ protein and activated NF-${\kappa}B$ p65 in LPS-unstimulated PBMCs, but had the opposite effect in LPS-stimulated PBMCs. Notably, t10c12-CLA enhanced NF-${\kappa}B$ p65 binding activity in LPS-unstimulated PBMCs exposed to caffeic acid phenethyl ester (CAPE), a NF-${\kappa}B$ inhibitor. Conversely, it inhibited NF-${\kappa}B$ p65 binding activity in LPS-stimulated PBMCs exposed to CAPE. These results suggest that t10c12-CLA may have different actions under different physiological conditions, and that its effect may be associated with a change in NF-${\kappa}B$ p65 activity.

The aim of this study was to find out if Ku70/80, p53, EGFR and COX-2 expressions are associated with prognostic variables and to examine the survival rate in tonsillar squamous cell carcinoma. Subjects and Method： From October 1991 to April 2006, 52 cases of paraffin-embedded tonsillar specimens were obtained by surgical resection in the Asan Medical Center. All tissue samples were subjected to immunohistochemical staining for Ku70/80, p53, EGFR and COX-2. Clinical factors such as age, treatment modality, TNM stage were evaluated nad detailed analyses were performed regarding the relationship between the expression of molecular markers, overall survival and disease free survival rates. Results：In the Ku70 expression, there were no cells that did not stain and 3 cases where less than 75% of cells stained positive. In the Ku80 expression, there was one case that did not stain and 3 cases where less than 75% of cells that stained positive. The positivity of p53, EGFR and COX-2 was 19% (10/52), 2% (1/52), 50% (26/52), respectively. There was a significant correlation between p53 and survival (overall and disease free) in the univariate analysis (p=0.049, p=0.017). However, there was no correlation in the multivariate survival analysis (p=0.187, p=0.078). Conclusion：This study finds that the expression of p53 correlates with an unfavorable prognosis in tonsillar squamous cell carcinoma. The p53 protein can be a biological marker for prediction of prognosis in tonsillar squamous cell carcinoma. (Korean J Otorhinolaryngol-Head Neck Surg 2008;51:70-6)

In this study, 20.8% of a p-type Si bifacial solar cell was used to develop a photovoltaic (PV) module to obtain the maximum power under a limited installation area. The transparent back sheet material was replaced during fabrication with a white one, which is opaque in commercial products. This is very beneficial for the generation of more electricity, owing to the additional power generation via absorption of light from the rear side. A new model is suggested herein to predict the power of the bifacial PV module by considering the backside reflections from the roof and/or environment. This model considers not only the frontside reflection, but also the nonuniformity of the backside light sources. Theoretical predictions were compared to experimental data to prove the validity of this model, the error range for which ranged from 0.32% to 8.49%. Especially, under $700W/m^2$, the error rate was as low as 2.25%. This work could provide theoretical and experimental bases for application to a distributed and microgrid network.

Background : Under hypoxia, hypoxia-inducible factor-1α (HIF-1α) is known to activate the expression of various genes, including angiogenesis-related genes. The aim of this study was to evaluate the expression of HIF-1α protein and its relationship with p53 protein expression and angiogenesis in the squamous cell carcinoma (SCC) of the uterine cervix. Methods : Using immunohistochemical methods, the expression of HIF-1α protein, p53 protein, vascular endothelial growth factor (VEGF), and microvessel count were evaluated in seventy cases of FIGO stages I and II SCC; and their results were compared with age, stage, and pelvic lymph node metastasis. Results : Positive nuclear staining for HIF-1α protein was noted in 19 cases (27.1%). Carcinoma in situ or dysplastic lesions also revealed positive nuclear reaction along the lower part of the epithelium. The expression of HIF-1α protein was significantly related with those of p53 protein and VEGF (p<0.05), but not with other clinicopathologic parameters. The microvessel count showed a significant difference regarding stage and VEGF expression (p<0.05). Conclusion : These findings suggest that HIF-1α expression in SCCs of the uterine cervix might be the early event of carcinogenesis and could be associated with p53 protein and VEGF expression. However, the prognostic significance of HIF-1α expression in stages I and II SCCs is undetermined.

In this paper we consider a more general class of centralizers called I-centralizers. More precisely, given a prime ideal P of an arbitrary ring R we establish a connection between certain algebraic identities involving a pair of P-left centralizers and the structure of the factor ring R/P.

Apoptosis, the cel's intrinsic death program, plays a crucial role in the regulation of tisue ho-meostasis, and abnormal inhibition of apoptosis is an indicator of cancer and autoimune diseases, whereas excessive cell death is implicated in neu-ease (AD). Using cDNA subtraction analysis, we compared p60TRP (p60 transcription regulator pro-tein) expresing cels with control cels during the process of apoptosis and we identified the new zinc-finger protein p48ZnF that is predominantly located in the cytoplasm of the cell. Aditionally, we demonstrate here that p48ZnF is up-regulated in rat neuronal PC12 cells upon stimulation with the neurotrophic factor NGF (50 ng/ml). These in the control of neuronal survival.

Background: Basaloid squamous cell carcinoma (BSCC) is a rare variant of squamous cell carcinoma with distinct pathologic characteristics. The histogenesis of BSCC is not fully understood, and the cancer has been suggested to originate from a totipotent primitive cell in the basal cell layer of the surface epithelium or in the proximal duct of secretory glands. Methods: Twenty-six cases of head and neck BSCC from Asan Medical Center, Seoul, Korea, reported during a 14-year-period were subclassified into basal, ductal, and mixed subtypes according to the expression of basal (cytokeratin [CK] 5/6, p63) or ductal markers (CK7, CK8/18). The cases were also subject to immunohistochemical study for CK19, p53, cyclin D1, epidermal growth factor receptor (EGFR), and p16 and to in situ hybridization for human papillomavirus (HPV), and the results were clinico-pathologically compared. Results: Mixed subtype (12 cases) was the most common, and these cases showed hypopharyngeal predilection, older age, and higher expression of CK19, p53, and EGFR than other subtypes. The basal subtype (nine cases) showed frequent comedo-necrosis and high expression of cyclin D1. The ductal subtype (five cases) showed the lowest expression of p53, cyclin D1, and EGFR. A small number of p16- and/or HPV-positive cases were not restricted to one subtype. BSCC was the cause of death in 19 patients, and the average follow-up period for all patients was 79.5 months. Overall survival among the three subtypes was not significantly different. Conclusions: The results of this study suggest a heterogeneous pathogenesis of head and neck BSCC. Each subtype showed variable histology and immunoprofiles, although the clinical implication of heterogeneity was not determined in this study.

본 연구에서는 C2C12 근육 세포에서 IGF-I이 리간드 비의존적으로 엔드로젠 수용체 coactivator 유전자 발현에 미치는 영향에 대해 알아보았다. 그 결과 IGF-I 이 리간드 비의존적으로 엔드로젠 수용체의 coactivator인 GRIP-1, SRC-1, ARA70 유전자들의 단백질과 mRNA 발현을 증가시켰으며, p38 MAPK와 ERK1/2 신호전달 경로 억제제인 SB203580과 PD98059를 IGF-I과 함께 처리한 결과 IGF-I에 의한 엔드로젠 수용체 coactivator 유전자 발현의 증가를 감소시켰음을 알 수 있었다. 엔드로젠 수용체 coactivator가 엔드로젠 물질이 없이도 IGF-I에 의해 발현이 증가하였다는 사실은 운동에 의해 근육에서 분비가 증가하는 IGF-I이 리간드 비의존적으로 근육 세포에서 엔드로젠 수용체 활성화 안정에 기여하는 엔드로젠 수용체 coactivator를 활성화 시킬 수 있다는 사실을 증명 하였다는데 의의가 있다고 사료된다. 또한, IGF-I의 하부신호전달 경로로 잘 알려진 p38 MAPK와 ERK1/2 신호전달 경로를 차단하였을 때는 발현이 억제되었는데 이를 통해 IGF-I이 근육세포 내에서 p38 MAPK, ERK1/2 경로를 통해 엔드로젠 수용체 coactivator 발현에 중요한 역할을 한다는 사실을 확인할 수 있었다. 이러한 결과는 근육에서 중요한 기능을 담당하는 IGF-I이 엔드로젠 수용체 coactivator 유전자 발현을 조절하는 기능이 있으며 이러한 IGF-I에 의한 리간드 비의존적인 엔드로젠 수용체 coactivator 유전자 발현 조절에 있어 p38 MAPK와 ERK1/2는 필수적인 신호전달 경로임을 확인하였다는 데서 그 의의가 있다고 할 수 있겠다. 향후 다양한 성장인자들에 의한 coactivator 발현에 관한 연구를 비롯하여, corepressor의 발현 억제 기능 및 신호전달 경로에 관한 연구가 추가적으로 이루어져야 할 것이다.

Although insulin-like growth factor-I (IGF-I) and androgen receptor (AR) coactivators are well known effectors of skeletal muscle, the molecular mechanism by which signaling pathways integrating AR coactivators and IGF-I in skeletal muscle cells has not been previously examined. In this study, the effects of IGF-I treatment on the gene expression of AR coactivators in the absence of AR ligands and the roles of the p38 MAPK and ERK1/2 signaling pathways in IGF-I-induced AR coactivators induction were examined. C2C12 cells were treated with 250 ng/ml of IGF-I in the presence or absence of specific inhibitors p38 MAPK (SB203580) or ERK1/2 (PD98059). Treatment of C2C12 cells with IGF-I resulted in increased in GRIP-1, SRC-1, and ARA70 protein expression. The levels of GRIP-1, SRC-1, and ARA70 mRNA were also significantly increased after 5min of IGF-I treatment. IGF-I-induced AR coactivator proteins were significantly blocked by pharmacological inhibitors of p38 MAPK and ERK1/2 pathways. However, there was no significant effect of those inhibitors on IGF-I-induced mRNA level of AR coactivators, suggesting that AR coactivators are post-transcriptionally regulated by IGF-I. Furthermore, the present results suggest that IGF-I stimulates the expression of AR coactivators by cooperative activation of the p38 MAPK and ERK1/2 pathways in C2C12 mouse skeletal muscle cells.