检索结果-南通市图书馆

Expression of E-cadherin and α-catenin in a varicocele-induced infertility rat model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2011年第3期13卷 470-475,514页

作者： Hong Koo Ha Hyun Jun park Nam Cheol park Department of Urology Pusan National University School of Medicine Busan 602739 Korea Medical Research Institute Pusan National University Hospital Busan 602739 Korea

The roles of E-cadherin and α-catenin were evaluated in the development of varicocele-induced infertility. Analysis of the association between the expression of E-cadherinla-catenin and clinical/pathological parameters was performed. Thirty lO-week-old male rats （experimental group） were used for the experiments; the left renal vein was ligated to form a varicocele. The abdomen was incised in 30 rats （control group） and no procedure was performed on 10 rats （baseline group）. The weights of the left testis, serum reactive oxygen species （ROS）, testosterone, luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and degenerative changes in the seminiferous tubules after 4 and 8 weeks were recorded. The expression of E-cadherin and α-catenin was evaluated by immunohistochemical （IHC） staining and Western blot analysis. The ROS increased in the 8-week experimental group, compared with the baseline and control groups （P〈0.001 for both）. Additionally, FSH significantly increased in the 4- and 8-week experimental group compared with the control groups （P= 0.013 and P= 0.032, respectively）. The ratio of degenerative changes in the seminiferous tubules of the experimental groups increased. The IHC staining showed that the expression of E-cadherin and a-catenin decreased in the 4- and 8-week experimental groups. Similar to the IHC staining, the experimental group had decreased reactivity on Western blot analysis. The expression of E-cadherin and a-catenin was significantly associated with the ROS and degenerative changes in the seminiferous tubules. The results of this study suggest that damage to the blood-testis barrier （BTB） is associated with varicocele-induced male infertility, and that ROS may cause damage to the BTB.

关键词： α-catenin blood-testis barrier E-cadherin varicocele infertility

Efficient Data Access for Location-Dependent Spatial Queries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2014年第3期29卷 449-469页

作者： Kwangjin park Department of Information Communication Engineering Wonkwang UniversityIksanChunbukKorea

When the mobile environment consists of light-weight devices, the loss of network connectivity and scarce resources, e.g., low battery power and limited memory, become primary issues of concern in order to efficiently support portable wireless devices. In this paper, we propose an index-based peer-to-peer data access method that uses a new Hierarchical Location-Based Sequential （HLBS） index. We then propose a novel distributed Nearest First Broadcast （NFB） algorithm. Both HLBS and NFB are specifically designed for mobile peer-to-peer service in wireless broadcast environments. The system has a lower response time, because the client only contacts a qualified service provider by accessing the HLBS and quickly retrieves the data to answer the query by using NFB. HLBS and NFB design the index for spatial objects according to the positions of individual clients and transfer the index in the order arranged so that the spatial query can be processed even after the user tunes the partial index. Hence, this design can support rapid and energy-efficient service. A performance evaluation is conducted to compare the proposed algorithms with algorithms based on R-tree and Hilbert-curve air indexes. The results show that the proposed data dissemination algorithm with the HLBS index is scalable and energy efficient in both range queries and nearest neighbor queries.

关键词： spatial index data broadcasting location-based service

Zwitterion-assisted transition metal dichalcogenide nanosheets for scalable and biocompatible inkjet printing

在线全文

学校读者我要写书评

暂无评论

Nano Research 2020年第10期13卷 2726-2734页

作者： Hyeokjung Lee Min Koo Chanho park Madhumita Patel Hyowon Han Tae Hyun park Pawan Kumar Won-Gun Koh Cheolmin park Department of Materials Science and Engineering Yonsei University Seoul 03722Republic of Korea Department of Chemical and Biomolecular Engineering Yonsei UniversitySeoul 03722Republic of Korea

Inkjet printing of two-dimensional(2D)transition metal dichalcogenide(TMD)nanosheets fabricated by liquid-phase exfoliation(LPE)allows simple,mass-producible,and low-cost photo-electronic *** LPE processes involve toxic and environmentally hazardous solvents;however,dispersants have restricted the extent of applications of 2D-TMD ***,various 2D-TMD nanosheets,including MoS2,MoSe2,WS2,and WSe2,in addition to few-layered graphene,are inkjet-printed using a LPE process based on zwitterionic dispersants in *** with cationic and anionic species are water-soluble,while alkyl chain moieties associated with two ionic species adhere universally on the surface of TMD nanosheets,resulting in high throughput liquid exfoliation of the *** zwitterion-assisted TMD nanosheets in water are successtully employed as an ink without the need for additives to adjust the viscosity and surface tension of the ink for use in an office inkjet printer;this gives rise to A4 scale,large-area inkjet-printed images on diverse substrates,such as metals,oxides,and polymer substrates patchable onto human *** with conductive graphene nanosheet inks allowed the development of mechanically flexible,biocompatible-printed arrays of photodetectors with pixelated MoSe2 channels on a paper exhibiting a photocurrent ON/OFF ratio of approximately 1038 and photocurrent switching of 500 ms.

关键词： transition metal dichalcogenide nanosheets zwitterions zwitterion-assisted liquid-phase exfoliation scalable inkjet printing biocompatible

Predictive factors for early distant metastasis after neoadjuvant chemoradiotherapy in locally advanced rectal cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2021年第4期13卷 252-264页

作者： Hyojung park Departments of Radiation Oncology Dankook University HospitalDankook University College of MedicineCheonan 46115South Korea

BACKGROUND Distant relapse is the leading cause of cancer-related death in locally advanced rectal *** chemoradiation(NACRT)followed by surgery inevitably delays delivery of systemic *** patients show early distant metastasis before systemic *** To identify the most effective *** investigated prognostic factors for distant metastasis,especially early distant metastasis,using the standard treatment paradigm to identify the most effective treatments according to recurrence *** From January 2015 through December 2019,rectal cancer patients who underwent NACRT for having clinical T 3-4 or clinical N 1-2 disease according to the 8th American Joint Committee on Cancer staging system were *** was delivered to the whole pelvis with concomitant *** received surgery 6-8 wk after completion of *** chemotherapy was administered at the physician’s *** A total of 127 patients received ***-three patients(73.2%)underwent *** R0 resection rate was 89.2%in all *** tumor and node downstaging rates were 41.9%and 76.3%.Half the patients(n=69)received adjuvant chemotherapy after *** 3-year distant metastasis-free survival(DMFS)and overall survival(OS)rates were 81.7%and 83.5%.On univariate analyses,poorly differentiated tumors,>5 cm,involvement of mesorectal fascia(MRF),or presence of extramural involvement(EMVI)were associated with worse DMFS and *** patients showed distant metastasis at their first evaluation after *** with early distant metastasis were more likely to have poorly differentiated tumor(P=0.025),tumors with involved MRF(P=0.002),and EMVI(P=0.012)than those who did *** EMVI,the involvement of MRF,and poor histologic grade were associated with early distant *** order to control distant metastasis and improve treatment outcome,selective use of neoadjuvant treatment according to indivi

关键词： Rectal cancer Neoadjuvant chemoradiotherapy Distant metastasis Extramural venous invasion

COMPUTATION OF NONEQUILIBRIUM HYPERSONIC FLOW OVER CONCAVE CORNERS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2001年第6期19卷 617-628页

作者： Taehoon park You-lan Zhu Kookmin University 韩国 136-702 The University of North Carolina 美国

Discusses a technique for the computation of hypersonic flow of air with chemical reactions over concave corners. Details of smooth transformation of domain; Use of finite difference method; Numerical results.

关键词： Shock fitting Smooth transformation of domain Finite difference method Implicit method.

Availability Analysis of Application Servers Using Software Rejuvenation and Virtualization

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2009年第2期24卷 339-346页

作者： Thandar Thein Jong Sou park Department Korea Aerospace University

Demands on software reliability and availability have increased tremendously due to the nature of present day applications. We focus on the aspect of software for the high availability of application servers since the unavailability of servers more often originates from software faults rather than hardware faults. The software rejuvenation technique has been widely used to avoid the occurrence of unplanned failures, mainly due to the phenomena of software aging or caused by transient failures. In this paper, first we present a new way of using the virtual machine based software rejuvenation named VMSR to offer high availability for application server systems. Second we model a single physical server which is used to host multiple virtual machines （VMs） with the VMSR framework using stochastic modeling and evaluate it through both numerical analysis and SHARPE （Symbolic Hierarchical Automated Reliability and Performance Evaluator） tool simulation. This VMSR model is very general and can capture application server characteristics, failure behavior, and performability measures. Our results demonstrate that VMSR approach is a practical way to ensure uninterrupted availability and to optimize performance for aging applications.

关键词： availability modeling software aging software rejuvenation virtual machine

Steam activation of Fe-N-C catalyst for advanced power performance of alkaline hydrazine fuel cells

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第1期31卷 276-285,I0008页

作者： Sooan Bae Jihyeon park Yuna Hwang Jin-Soo park Jaeyoung Lee Beomgyun Jeong Research Center for Materials Analysis Korea Basic Science Institute169-14&Gwahak-roDaejeon 34133Republic of Korea School of Earth Sciences and Environmental Engineering Gwangju Institute of Science and Technology123 Cheomdangwagi-ro.Buk-guGwangju 61005Republic of Korea Department of Green Chemical Engineering Sangmyung University31 Sangmyungdae-gilDongnam-gu.CheonanChungnam Province 31066Republic of Korea Ertl Center for Electrochemistry and Catalysis Gwangju Institute of Science and Technology123 Cheomdangwagi-roBuk-giiGwangju 61005Republic of Korea

Alkaline hydrazine liquid fuel cells(AHFC) have been highlighted in terms of high power performance with non-precious metal *** Fe-N-C is a promising non-Pt electrocatalyst for oxygen reduction reaction(ORR),the surface density of the active site is very low and the catalyst layer should be thick to acquire the necessary number of catalytic active *** this thick catalyst layer,it is important to have an optimum pore structure for effective reactant conveyance to active sites and an interface structure for faster charge ***,we prepare a Fe-N-C catalyst with magnetite particles and hierarchical pore structure by steam *** steam activation process significantly improves the power performance of the AHFC as indicated by the lower IR and activation voltage *** on a systematic characterization,we found that hierarchical pore structures improve the catalyst utilization efficiency of the AHFCs,and magnetite nanoparticles act as surface modifiers to reduce the interracial resistance between the electrode and the ion-exchange membrane.

关键词： Alkaline hydrazine fuel cell Oxygen reduction reaction Electrocatalyst Steam activation Ohmic loss Interfacial resistance Surface modifier

The electronic structure and intervalley coupling of artificial and genuine graphene superlattices

在线全文

学校读者我要写书评

暂无评论

Nano Research 2016年第4期9卷 1101-1115页

作者： Pilkwang Kim Cheol-Hwan park Department of Physics and Astronomy Seoul National University Seou108826 Republic of Korea

The so-called artificial graphene is an artificial material whose low-energy carriers are described by the massless Dirac equation. Applying a periodic potential with triangular symmetry to a two-dimensional electron gas is one approach to make such a material. According to recent experimental results, it is now possible to realize artificial graphene in the lab and to even apply an additional lateral, one-dimensional periodic potential to it. We name the latter system an artificial graphene superlattice in order to distinguish it from a genuine graphene superlaedce made from graphene. In this study, we investigate the electronic structure of artificial graphene superlattices, which exhibit the emergence of energy band gaps, merging and splitting of the Dirac points, etc. Then, from a similar investigation on genuine graphene superlattices, we show that many of these features originate from the coupling between Dirac fermions residing in two different valleys--the intervaUey coupling. Furthermore, contrary to previous studies, we find that the effects of intervalley coupling on the electronic structure cannot be ignored, irrespective of the length of the spatial period of the superlattice.

关键词： graphene artificial graphene graphene superlattice intervaUey coupling

Decomposition of Nitrogen Trifluoride Using Low Power Arc Plasma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2013年第9期15卷 923-927页

作者： Jee-Hun KO Sooseok CHOI Hyun-Woo park Dong-Wha park Department of Chemical Engineering and Regional Innovation Center for Environmental Technology of Thermal Plasma (RIC-ETTP)INHA University253 Yonghyun-dongNam-guIncheon 402-751Republic of Korea Department of Environmental Chemistry and Engineering Tokyo Institute of Technology 4259-G1-22Nagatsuta-choMidori-kuYokohama 226-8502Japan

The low power arc plasma is characterized by extremely high enthalpy and temper- ature and it is easy to generate and control, and thus thermal decomposition process based on the plasma torch is receiving a great attention for decomposing non-degradable greenhouse gases. In order to elevate the economic feasibility, the effects of input power, waste gas flow rate and additive gases on the destruction and removal efficiency （DRE） of NF3 are examined. Specific energy density （SED） deceases as the flow rate increases, and accordingly, the DRE is reduced. The DRE is basically determined by the specific energy density. The highest DRE of NF3 was 97% for the waste gas flow rate of 100 L/min at a low input power level of 2 kW with the help of hydrogen additional gas. The inlet and outlet concentration of NF3 was analyzed using Fourier transform infrared spectroscopy （FT-IR） for DRE of NF3 evaluation. As a result, large amount of NF3 can be efficiently decomposed by low power arc plasma systems.

关键词： arc plasma decomposition nitrogen trifluoride