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Application of LCA by Using Midpoint and Endpoint Interpretations for Urban Solid Waste Management 被引量:1
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作者 Sora Yi Kiyo H. Kurisu Keisuke Hanaki 《Journal of Environmental Protection》 2014年第12期1091-1103,共13页
Life cycle assessment (LCA) is one of the most widely used methods of decision support. However, few studies have examined whether stakeholders prefer midpoint or endpoint approaches. In this regard, the present study... Life cycle assessment (LCA) is one of the most widely used methods of decision support. However, few studies have examined whether stakeholders prefer midpoint or endpoint approaches. In this regard, the present study examines the attitudes toward urban solid waste management, environmental issues, and scenario evaluations by using midpoint and endpoint interpretations of LCA results. This study introduces three types of social groups that typically respond to environmental conflicts: the individualist, hierarchist, and egalitarian groups. Although residents are likely to recognize global impacts as the most important issue, their view is likely to change depending on system and avoided emissions. Consistent with the Seoul Metropolitan Area’s new policy designed to increase the incineration ratio, almost half of all respondents preferred the scenario. Noteworthy is that the respondents’ preference for midpoint and endpoint decision-making tools is not consistent with that in previous studies. Most of the respondents indicated that the midpoint approach would be better in evaluating environmental systems. 展开更多
关键词 LCIA ENVIRONMENTAL Impact ENVIRONMENTAL Damage Cultural Theory LIME Social PREFERENCE NIMBY
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Effectiveness and adverse effects of hormonal therapy for prostate cancer: Japanese experience and perspective
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作者 Mikio Namiki Satoru Ueno +2 位作者 Yasuhide Kitagawa Takashi Fukagai Hideyuki Akaza 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第3期451-457,I0007,I0008,共9页
Recently, novel anti-androgens and inhibitors of androgen biosynthesis have been developed through the elucidation of mechanisms of castration resistance of prostate cancer. We believe that these new developments will... Recently, novel anti-androgens and inhibitors of androgen biosynthesis have been developed through the elucidation of mechanisms of castration resistance of prostate cancer. We believe that these new developments will improve hormonal therapy. On the other hand, there has been an increase in criticism of hormonal therapy, because hormonal therapy is supposed to induce adverse effects such as cardiovascular disease. In this review, we have introduced the Japanese experience of hormonal therapy, because we believe that there may be ethnic differences between Caucasians and Asian people in the efficacy and adverse effects of hormonal therapy. First, we showed that primary hormonal therapy can achieve long-term control of localized prostate cancer in some cases and that quality of life of patients receiving hormonal therapy is rather better than previously thought. Neoadjuvant and adjuvant hormonal therapy in cases undergoing radical prostatectomy or radiotherapy are very useful for high-risk or locally advanced prostate cancer. Further clinical trials are required to confirm the efficacy of neoadjuvant or adjuvant hormonal therapy. We showed that the death from cardiovascular dis- eases in Japanese patients receiving hormonal therapy was not higher than that in the general population. However; efforts should be made to decrease the adverse effects of hormonal therapy, because life-style change may increase the susceptibility to adverse effects by hormonal therapy even in Japan. Managements of endocrine and metabolic dysfunction, such as diabetes mellitus, are essential. New hormonal compounds such as selective androgen receptor modulators capable of specifically targeting prostate cancer are expected to be developed. 展开更多
关键词 adverse effects androgen deprivation therapy hormonal therapy prostate cancer
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Indo-Western Pacific Ocean Capacitor and Coherent Climate Anomalies in Post-ENSO Summer: A Review 被引量:99
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作者 Shang-Ping XIE Yu KOSAKA +3 位作者 Yan DU Kaiming HU Jasti S.CHOWDARY Gang HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第4期411-432,共22页
ENSO induces coherent climate anomalies over the Indo-western Pacific, but these anomalies outlast SST anomalies of the equatorial Pacific by a season, with major effects on the Asian summer monsoon. This review provi... ENSO induces coherent climate anomalies over the Indo-western Pacific, but these anomalies outlast SST anomalies of the equatorial Pacific by a season, with major effects on the Asian summer monsoon. This review provides historical accounts of major milestones and synthesizes recent advances in the endeavor to understand summer variability over the Indo-Northwest Pacific region. Specifically, a large-scale anomalous anticyclone (AAC) is a recurrent pattern in post-E1 Nifio summers, spanning the tropical Northwest Pacific and North Indian oceans. Regarding the ocean memory that anchors the summer AAC, competing hypotheses emphasize either SST cooling in the easterly trade wind regime of the Northwest Pacific or SST warming in the westerly monsoon regime of the North Indian Ocean. Our synthesis reveals a coupled ocean- atmosphere mode that builds on both mechanisms in a two-stage evolution. In spring, when the northeast trades prevail, the AAC and Northwest Pacific cooling are coupled via wind-evaporation-SST feedback. The Northwest Pacific cooling persists to trigger a summer feedback that arises from the interaction of the AAC and North Indian Ocean warming, enabled by the westerly monsoon wind regime. This Indo-western Pacific ocean capacitor (IPOC) effect explains why E1 Nifio stages its last act over the monsoonal Indo-Northwest Pacific and casts the Indian Ocean warming and AAC in leading roles. The IPOC displays interdecadal modulations by the ENSO variance cycle, significantly correlated with ENSO at the turn of the 20th century and after the 1970s, but not in between. Outstanding issues, including future climate projections, are also discussed. 展开更多
关键词 Indian Ocean western Pacific ocean-atmosphere interaction ENSO Asian monsoon
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Microstructure evolution and mechanical properties of Al−3.6Cu−1Li alloy via cryorolling and aging 被引量:9
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作者 Chang LI Han-qing XIONG +5 位作者 Laxman BHATTA Lin WANG Zhao-yang ZHANG Hui WANG Charlie KONG Hai-liang YU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第11期2904-2914,共11页
An Al−3.6Cu−1Li alloy was subjected to room temperature rolling and cryorolling to investigate their effects on microstructure evolution and mechanical properties.The microstructure and aging characteristics of the ro... An Al−3.6Cu−1Li alloy was subjected to room temperature rolling and cryorolling to investigate their effects on microstructure evolution and mechanical properties.The microstructure and aging characteristics of the room temperature-rolled and the cryorolled alloys with 70%and 90%of thickness reductions were studied by microstructure analysis and mechanical tests.The samples subjected to cryorolling with 90%of thickness reduction have high strength and good toughness.This is mainly due to the inhibition of dynamic recovery and the accumulation of high-density dislocations in cryorolled samples.In addition,the artificial aging reveals that the temperature at which peak hardness is attained is inversely proportional to the deformation amount and directly proportional to the rolling temperature.Moreover,bright field images of cryorolled samples after aging indicate the existence of T1(Al2CuLi)precipitates.This suggests that the high stored strain energy enhances the aging kinetics of the alloy,which further promotes the nucleation of T1 phases. 展开更多
关键词 Al−Cu−Li alloy CRYOROLLING AGING precipitation strengthening mechanical property
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Recycle for Sludge Scrap of Nd-Fe-B Sintered Magnet as Isotropic Bonded Magnet 被引量:4
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作者 Masahiro Itoh Masahiro Masuda +1 位作者 Shunji Suzuki Ken-ichi Machida 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第1期168-171,共4页
The reduction diffusion method was performed for the sludge scrap of Nd-Fe-B sintered magnets with adding Ca metal to recover the oxidized Nd-Fe-B phase. After washing the resultant powders to remove Ca metal componen... The reduction diffusion method was performed for the sludge scrap of Nd-Fe-B sintered magnets with adding Ca metal to recover the oxidized Nd-Fe-B phase. After washing the resultant powders to remove Ca metal component, the powders obtained were recycled as an isotropic magnetic powder by the melt spinning method. The magnetic properties of powders as recycled were inferior, especially for the coercivity value, due to the deletion of rare earth metals during the washing process. The adjustment of metal composition, i.e., the addition of Nd metal, at the melt spinning process improved the magnetic properties to be B r=~0.75 T, H cj=~0.93 mA·m -1, and (BH) max=~91 kJ·m -3. The magnetic properties of the bonded magnets prepared from the composition-adjusted powders were B r=~0.66 T, H cj=~0.92 mA·m -1, and (BH) max=~70 kJ·m -3, which are approximately comparable to the commercially available MQPB boned one (B r=~0.73 T, H cj=~0.79 mA·m -1, and (BH) max=~86 kJ·m -3). 展开更多
关键词 Nd-Fe-B sintered magnet recycling isotropic Nd-Fe-B bonded magnet melt-spinning method sludge scrap rare earths
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Microarray-based analysis for hepatocellular carcinoma: From gene expression profiling to new challenges 被引量:5
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作者 Yutaka Midorikawa Masatoshi Makuuchi +1 位作者 Wei Tang Hiroyuki Aburatani 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第10期1487-1492,共6页
Accumulation of mutations and alterations in the expression of various genes result in carcinogenesis,and the development of microarray technology has enabled us to identify the comprehensive gene expression alteratio... Accumulation of mutations and alterations in the expression of various genes result in carcinogenesis,and the development of microarray technology has enabled us to identify the comprehensive gene expression alterations in oncogenesis.Many studies have applied this technology for hepatocellular carcinoma(HCC),and identified a number of candidate genes useful as biomarkers in cancer staging,prediction of recurrence and prognosis,and treatment selection.Some of these target molecules have been used to develop new serum diagnostic markers and therapeutic targets against HCC to benefit patients.Previously,we compared gene expression profiling data with classification based on clinicopathological features,such as hepatitis viral infection or liver cancer progression.The next era of gene expression analysis will require systematic integration of expression profiles with other types of biological information,such as genomic locus,gene function,and sequence information.We have reported integration between expression profiles and locus information,which is effective in detecting structural genomic abnormalities,such as chromosomal gains and losses,in which we showed that gene expression profiles are subject to chromosomal bias.Furthermore,array-based comparative genomic hybridization analysis and allelic dosage analysis using genotyping arrays for HCC were also reviewed,with comparison of conventional methods. 展开更多
关键词 Liver cancer IVlicroarray
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Demonstration of Automatic Impedance-Matching and Constant Power Feeding to and Electric Helicopter via Magnetic Resonance Coupling 被引量:1
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作者 Masato Yamakawa Kohei Shimamura +1 位作者 Kimiya Komurasaki Hiroyuki Koizumi 《Wireless Engineering and Technology》 2014年第3期45-53,共9页
Wireless power transfer (WPT) from a transmitter resonator on the ground to an electrically powered miniature heli-copter was attempted to demonstrate WPT using magnetic resonance coupling to an object moving in 3D sp... Wireless power transfer (WPT) from a transmitter resonator on the ground to an electrically powered miniature heli-copter was attempted to demonstrate WPT using magnetic resonance coupling to an object moving in 3D space. The transmission efficiency was optimized by automatic impedance matching for different flight attitudes: a maximum flight altitude of 590 mm was achieved. Furthermore, an estimation method of transmission efficiency using only the properties on the transmitter side was proposed, with transmission power regulated as constant against the change in the coupling coefficient. 展开更多
关键词 Wireless POWER Transfer POWER Regulation RESONATOR FLYING Object
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Evaluation on Information Model about Sensors Featured by Relationships to Measured Structural Objects 被引量:1
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作者 Shinji Kikuchi Akihito Nakamura Daishi Yoshino 《Advances in Internet of Things》 2016年第3期31-53,共24页
In accordance with the requirements of expanding Machine-To-Machine communication (M2M), the network overlay is in progress in several domains such as Smart Grid. Consequently, it is predictable that opportunities and... In accordance with the requirements of expanding Machine-To-Machine communication (M2M), the network overlay is in progress in several domains such as Smart Grid. Consequently, it is predictable that opportunities and cases of integrating yielded data from devices such as sensors will increase more. Accordingly, the importance of Ontology and Information Models (IM) which normalize the semantics including sensor expressions, have increased, and the standards of these definitions have been more important as well. So far, there have been multiple initiatives for standardizing the Ontology and IM in regards to the sensors expression such as Sensor Standards Harmonization by the National Institute of Standards and Technology (NIST), W3C Semantic Sensor Network (SSN) and the recent W3C IoT-Lite Ontology. However, there is still room to improve the current level of the Ontology and IM on the viewpoint of the implementing structure. This paper presents a set of IMs on abstract sensors and contexts in regards to the phenomenon around these sensors from the point of view of a structure implementing these specified sensors. As several previous studies have pointed out, multiple aspects on the sensors should be modeled. Accordingly, multiple sets of Ontology and IM on these sensors should be defined. Our study has intended to clarify the relationship between configurations and physical measured quantities of the structures implementing a set of sensors. Up to present, they have not been generalized and have remained unformulated. Consequently, due to the result of this analysis, it is expected to implement a more generalized translator module easily, which aggregates the measured data from the sensors on the middleware level managing these Ontology and IM, instead of the layer of user application programs. 展开更多
关键词 Sensor Information Model ONTOLOGY Semantic Integration Data Aggregation
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Asian trends in primary androgen depletion therapy on prostate cancer
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作者 Hideyuki Akaza 《Cancer Biology & Medicine》 SCIE CAS CSCD 2013年第4期187-191,共5页
There are notable differences in the incidence and mortality rates for prostate cancer between Asia and Western countries.It is also recognized that there are differences in thinking with regard to treatment options.R... There are notable differences in the incidence and mortality rates for prostate cancer between Asia and Western countries.It is also recognized that there are differences in thinking with regard to treatment options.Recently it is also the case that opinions have been reported concerning the differences between Asian and Western patients with regard to their reaction to androgen depletion therapy(ADT).Given that ADT is a method of treatment that focuses on the elimination of testosterone,an inevitable symptom of its administration is testosterone losing syndrome.It is for this reason that in Western countries ADT has only been recommended in cases of advanced or metastatic cancer.On the other hand,in Asia,ADT is used in relatively many cases,including non-metastatic localized cancer and invasive localized cancer.To date,however,there has been little substantive discussion concerning this difference in utilization of ADT.ADT-related drugs for prostate cancer and the development of new drugs for castration resistant prostate cancer(CRPC)have been actively tested in recent years.It could be the case that analyzing the differences in concepts about ADT between Asia and the West could contribute to the effective use of ADT-related drugs and also help to build new treatment strategies for prostate cancer. 展开更多
关键词 Androgen depletion therapy prostate cancer ASIA
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Growth and Characterization of Modulation-Doped Al_(x)Ga_(1-x)N/GaN Heterostructures
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作者 SHEN Bo ZHANG Rong +3 位作者 SHI Yi ZHENG You-Dou T.Someya Y.Arakawa 《Chinese Physics Letters》 SCIE CAS CSCD 2001年第1期129-131,共3页
The modulation-doped Al_(0.22)Ga_(0.78)N/GaN heterostructures with different Al_(0.22)Ga_(0.78)N barrier thicknesses were grown by means of metal--organic chemical vapour deposition.The Al_(0.22)Ga_(0.78)N layer still... The modulation-doped Al_(0.22)Ga_(0.78)N/GaN heterostructures with different Al_(0.22)Ga_(0.78)N barrier thicknesses were grown by means of metal--organic chemical vapour deposition.The Al_(0.22)Ga_(0.78)N layer still has pseudomorphic growth when its thickness is 53nm.The mobility of the two-dimensional electron gas(2DEG)at the heterointerfaces is much higher than that of the electrons in GaN films at both 300 and 77K.The dramatic decrease of the 2DEG mobility in an Al_(0.22)Ga_(0.78)N/GaN heterostructure corresponds to the partial relaxation of the Al_(0.22)Ga_(0.78)N barrier. 展开更多
关键词 N/Ga deposition MOBILITY
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Analysis of Impactful Factors on Performance in Combining Architectural Elements of IoT
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作者 Shinji Kikuchi Shodai Watanabe +3 位作者 Takahiro Kenmotsu Daishi Yoshino Akihito Nakamura Takafumi Hayashi 《Advances in Internet of Things》 2017年第4期121-138,共18页
We implemented a generalized infrastructure for Internet of Things (IoT infrastructure) to be applicable in various areas such as Smart Grid. That IoT infrastructure has two methods to store sensor data. They commonly... We implemented a generalized infrastructure for Internet of Things (IoT infrastructure) to be applicable in various areas such as Smart Grid. That IoT infrastructure has two methods to store sensor data. They commonly have the features of double overlay structure, virtualization of sensors, composite services as federation using publisher/subscriber. And they are implemented as synthesizing the elemental architectures. The two methods majorly have the common architectural elements, however there are differences in how to compose and utilize them. But we observed the non-negligible differences in their achieved performance by the actual implementations due to operational items beyond these architectural elements. In this paper, we present the results of our analysis about the factors of the revealed differences based on the measured performance. In particular, it is clarified that a negative side effect due to combining independent elemental micro solutions naively could be amplified, if maximizing the level of loose coupling is applied as the most prioritized design and operational policy. Primarily, these combinations should be evaluated and verified during the basic design phase. However, the variation of how to synthesize them tends to be a blind spot when adopting the multiple independent architectural elements commonly. As a practical suggestion from this case, the emphasized importance in carrying out a new synthetization with multiple architectures is to make a balance naturally among architectural elements, or solutions based on them, and there is a certain demand to establish a methodology for architectural synthetization, including verification. 展开更多
关键词 Sensor Data Management LOOSE Coupling OVERLAY Architecture PERFORMANCE ANALYSIS
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Pb(Zr0.53Ti0.47)O3/AlxGa1-xN/GaN异质结构的电容-电压特征(英文) 被引量:1
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作者 沈波 李卫平 +10 位作者 周玉刚 毕朝霞 张荣 郑泽伟 刘杰 周慧梅 施毅 刘治国 郑有炓 Someya T Arakawa Y 《发光学报》 EI CAS CSCD 北大核心 2001年第S1期57-60,共4页
通过在调制掺杂Al0 2 2 Ga0 78N/GaN异质结构上淀积Pb(Zr0 53 Ti0 4 7)O3 (PZT)铁电薄膜 ,我们发展了一种基于AlxGa1-xN/GaN异质结构的金属 铁电 半导体 (MFS)结构。在高频电容 电压 (C V)特性测量中 ,发现Al0 2 2 Ga0 78N/GaN... 通过在调制掺杂Al0 2 2 Ga0 78N/GaN异质结构上淀积Pb(Zr0 53 Ti0 4 7)O3 (PZT)铁电薄膜 ,我们发展了一种基于AlxGa1-xN/GaN异质结构的金属 铁电 半导体 (MFS)结构。在高频电容 电压 (C V)特性测量中 ,发现Al0 2 2 Ga0 78N/GaN异质界面二维电子气 ( 2DEG)的浓度在 -1 0V偏压下从 1 5 6× 1 0 13 cm-2 下降为 5 6× 1 0 12 cm-2 。由于PZT薄膜的铁电极化 ,在 -1 0V偏压下可以观察到宽度为 0 2V的铁电C V窗口 ,表明在没有铁电极化方向反转的条件下 ,PZT/AlxGa1-xN/GaNMFS结构也能出现存储特性。因为 2DEG带来的各种优点 ,可以认为AlxGa1-xN/GaN异质结构在以存储器为目标的MFS场效应晶体管中有重要应用。 展开更多
关键词 C-V特性 Pb(ZrTi)O3 铁电薄膜 ALXGA1-XN/GAN
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电容-电压法研究Al_xGa_(1-x)N/GaN异质结压电极化效应(英文) 被引量:1
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作者 俞慧强 沈波 +7 位作者 周玉刚 张荣 刘杰 周慧梅 施毅 郑有炓 Someya T Arakawa Y 《发光学报》 EI CAS CSCD 北大核心 2001年第z1期61-66,共6页
制备了基于调制掺杂Al0 2 2 Ga0 78N/GaN异质结的Pt/Al0 2 2 Ga0 78N/GaN肖特基二极管。由于Al0 2 2Ga0 78N势垒层中的极化场不同 ,不同Al0 2 2 Ga0 78N势垒层厚度的二极管的电容 电压特性显著不同。根据对样品电容 电压特性的... 制备了基于调制掺杂Al0 2 2 Ga0 78N/GaN异质结的Pt/Al0 2 2 Ga0 78N/GaN肖特基二极管。由于Al0 2 2Ga0 78N势垒层中的极化场不同 ,不同Al0 2 2 Ga0 78N势垒层厚度的二极管的电容 电压特性显著不同。根据对样品电容 电压特性的数值模拟 ,在Al0 2 2 Ga0 78N势垒层厚度为 30nm和 4 5nm的样品中 ,异质界面的极化电荷面密度为 6 78× 1 0 12 cm-2 。在Al0 2 2 Ga0 78N势垒层厚度为 75nm的样品中 ,极化电荷面密度降为 1 30×10 12 cm-2 。这种极化电荷面密度的降低是由于GaN上Al0 2 2 Ga0 78N势垒层由于厚度增加而产生应变的部分弛豫。本工作也提供了一种定量表征AlxGa1-xN/GaN异质结中极化电荷面密度的方法。 展开更多
关键词 压电极化 异质结 电容-电压方法
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Pb(Zr_(0.53)Ti_(0.47))O_3/Al_xGa_(1-x)N/GaN异质结构的电容-电压特征(英文)
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作者 沈波 李卫平 +10 位作者 周玉刚 毕朝霞 张荣 郑泽伟 刘杰 周慧梅 施毅 刘治国 郑有炓 Someya T Arakawa Y 《发光学报》 EI CAS CSCD 北大核心 2001年第z1期57-60,共4页
通过在调制掺杂Al0 2 2 Ga0 78N/GaN异质结构上淀积Pb(Zr0 53 Ti0 4 7)O3 (PZT)铁电薄膜 ,我们发展了一种基于AlxGa1-xN/GaN异质结构的金属 铁电 半导体 (MFS)结构。在高频电容 电压 (C V)特性测量中 ,发现Al0 2 2 Ga0 78N/GaN... 通过在调制掺杂Al0 2 2 Ga0 78N/GaN异质结构上淀积Pb(Zr0 53 Ti0 4 7)O3 (PZT)铁电薄膜 ,我们发展了一种基于AlxGa1-xN/GaN异质结构的金属 铁电 半导体 (MFS)结构。在高频电容 电压 (C V)特性测量中 ,发现Al0 2 2 Ga0 78N/GaN异质界面二维电子气 ( 2DEG)的浓度在 -1 0V偏压下从 1 5 6× 1 0 13 cm-2 下降为 5 6× 1 0 12 cm-2 。由于PZT薄膜的铁电极化 ,在 -1 0V偏压下可以观察到宽度为 0 2V的铁电C V窗口 ,表明在没有铁电极化方向反转的条件下 ,PZT/AlxGa1-xN/GaNMFS结构也能出现存储特性。因为 2DEG带来的各种优点 ,可以认为AlxGa1-xN/GaN异质结构在以存储器为目标的MFS场效应晶体管中有重要应用。 展开更多
关键词 C-V特性 Pb(ZrTi)O3 铁电薄膜 ALXGA1-XN/GAN
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电容-电压法研究AlxGa1-xN/GaN异质结压电极化效应(英文)
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作者 俞慧强 沈波 +7 位作者 周玉刚 张荣 刘杰 周慧梅 施毅 郑有炓 Someya T Arakawa Y 《发光学报》 EI CAS CSCD 北大核心 2001年第S1期61-66,共6页
制备了基于调制掺杂Al0 2 2 Ga0 78N/GaN异质结的Pt/Al0 2 2 Ga0 78N/GaN肖特基二极管。由于Al0 2 2Ga0 78N势垒层中的极化场不同 ,不同Al0 2 2 Ga0 78N势垒层厚度的二极管的电容 电压特性显著不同。根据对样品电容 电压特性的... 制备了基于调制掺杂Al0 2 2 Ga0 78N/GaN异质结的Pt/Al0 2 2 Ga0 78N/GaN肖特基二极管。由于Al0 2 2Ga0 78N势垒层中的极化场不同 ,不同Al0 2 2 Ga0 78N势垒层厚度的二极管的电容 电压特性显著不同。根据对样品电容 电压特性的数值模拟 ,在Al0 2 2 Ga0 78N势垒层厚度为 30nm和 4 5nm的样品中 ,异质界面的极化电荷面密度为 6 78× 1 0 12 cm-2 。在Al0 2 2 Ga0 78N势垒层厚度为 75nm的样品中 ,极化电荷面密度降为 1 30×10 12 cm-2 。这种极化电荷面密度的降低是由于GaN上Al0 2 2 Ga0 78N势垒层由于厚度增加而产生应变的部分弛豫。本工作也提供了一种定量表征AlxGa1-xN/GaN异质结中极化电荷面密度的方法。 展开更多
关键词 压电极化 异质结 电容电压方法
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Al_xGa_(1-x)N/GaN异质结二维电子气磁输运性质研究(英文)
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作者 郑泽伟 沈波 +11 位作者 刘杰 周慧梅 钱悦 张荣 施毅 郑有火斗 蒋春萍 郭少令 郑国珍 褚君浩 Someya T Arakawa Y 《发光学报》 EI CAS CSCD 北大核心 2001年第z1期67-70,共4页
在 1 5K低温和 0~ 9T的高磁场下研究了AlGaG/GaN异质结二维电子气的磁输运性质。实验结果在 4块样品中都观察到了Shubnikov daHass振荡的双周期行为。表明异质结的三角势阱中有两个子带被电子占据。通过电子子带占据时电子浓度分配的... 在 1 5K低温和 0~ 9T的高磁场下研究了AlGaG/GaN异质结二维电子气的磁输运性质。实验结果在 4块样品中都观察到了Shubnikov daHass振荡的双周期行为。表明异质结的三角势阱中有两个子带被电子占据。通过电子子带占据时电子浓度分配的线形行为得到第二子带被占据的阈值浓度为 7 2× 1 0 12 cm-2 。通过对不同样品量子散射时间和输运迁移率的研究 ,说明在 1 5K下远程离化施主散射在量子散射时间中起主要作用。 展开更多
关键词 磁传输特性 二维电子气 AlxG1-xN/GaN
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AlxGa1-xN/GaN异质结二维电子气磁输运性质研究(英文)
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作者 郑泽伟 沈波 +11 位作者 刘杰 周慧梅 钱悦 张荣 施毅 郑有炓 蒋春萍 郭少令 郑国珍 褚君浩 Someya T Arakawa Y 《发光学报》 EI CAS CSCD 北大核心 2001年第S1期67-70,共4页
在 1 5K低温和 0~ 9T的高磁场下研究了AlGaG/GaN异质结二维电子气的磁输运性质。实验结果在 4块样品中都观察到了Shubnikov daHass振荡的双周期行为。表明异质结的三角势阱中有两个子带被电子占据。通过电子子带占据时电子浓度分配的... 在 1 5K低温和 0~ 9T的高磁场下研究了AlGaG/GaN异质结二维电子气的磁输运性质。实验结果在 4块样品中都观察到了Shubnikov daHass振荡的双周期行为。表明异质结的三角势阱中有两个子带被电子占据。通过电子子带占据时电子浓度分配的线形行为得到第二子带被占据的阈值浓度为 7 2× 1 0 12 cm-2 。通过对不同样品量子散射时间和输运迁移率的研究 ,说明在 1 5K下远程离化施主散射在量子散射时间中起主要作用。 展开更多
关键词 磁传输特性 二维电子气 AlxG1-xN/GaN
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Accumulation of aberrant DNA methylation during colorectal cancer development 被引量:7
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作者 Eiji Sakai Atsushi Nakajima Atsushi Kaneda 《World Journal of Gastroenterology》 SCIE CAS 2014年第4期978-987,共10页
Despite the recent advances in the therapeutic modalities,colorectal cancer(CRC)remains to be one of the most common causes of cancer-related death.CRC arises through accumulation of multiple genetic and epigenetic al... Despite the recent advances in the therapeutic modalities,colorectal cancer(CRC)remains to be one of the most common causes of cancer-related death.CRC arises through accumulation of multiple genetic and epigenetic alterations that transform normal colonic epithelium into adenocarcinomas.Among crucial roles of epigenetic alterations,gene silencing by aberrant DNA methylation of promoter regions is one of the most important epigenetic mechanisms.Recent comprehensive methylation analyses on genome-wide scale revealed that sporadic CRC can be classified into distinct epigenotypes.Each epigenotype cooperates with specific genetic alterations,suggesting that they represent different molecular carcinogenic pathways.Precursor lesions of CRC,such as conventional and serrated adenomas,already show similar methylation accumulation to CRC,and can therefore be classified into those epigenotypes of CRC.In addition,specific DNA methylation already occurs in the normal colonic mucosa,which might be utilized for prediction of the personal CRC risk.DNA methylation is suggested to occur at an earlier stage than carcinoma formation,and may predict the molecular basis for future development of CRC.Here,we review DNA methylation and CRC classification,and discuss the possible clinical usefulness of DNA methylation as biomarkers for the diagnosis,prediction of the prognosis and the response to therapy of CRC. 展开更多
关键词 Colorectal cancer Colorectal adenoma Aberrant crypt foci Genetic mutation Epigenotype DNA methylation Colorectal carcinogenesis
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Gene expression profiles of hepatic cell-type specific marker genes in progression of liver fibrosis 被引量:5
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作者 Yoshiyuki Takahara Mitsuo Takahashi +5 位作者 Hiroki Wagatsuma Fumihiko Yokoya Qing-Wei Zhang Mutsuyo Yamaguchi Hiroyuki Aburatani Norifumi Kawada 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第40期6473-6499,共27页
AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cel... AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cells, including hepatic stellate cells (HSCs), Kupffer cells (including other inflammatory cells), and hepatocytes, using independent temporal DNA microarray data obtained from isolated hepatic cells. RESULTS: The cell-type analysis of gene expression gave several key results and led to formation of three hypotheses: (1) changes in the expression of HSC-specific marker genes during fibrosis were similar to gene expression data in in vitro cultured HSCs, suggesting a major role of the self-activating characteristics of HSCs in formation of fibrosis; (2) expression of mast cell-specific marker genes reached a peak during liver fibrosis, suggesting a possible role of mast cells in formation of fibrosis; and (3) abnormal expression of hepatocyte-specific marker genes was found across several metabolic pathways during fibrosis, including sulfur-containing amino acid metabolism, fatty acid metabolism, and drug metabolism, suggesting a mechanistic relationship between these abnormalities and symptoms of liver fibrosis. CONCLUSION: Analysis of marker genes for specific hepatic cell types can identify the key aspects of fibro-genesis. Sequential activation of inflammatory cells and the self-supporting properties of HSCs play an important role in development of fibrosis. 展开更多
关键词 Liver fibrosis Gene expression Microarray DIMETHYLNITROSAMINE Marker genes Hepatic stellate cell Kupffer cell HEPATOCYTES Metabolic pathway
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Calibration and validation of a simulation model for predicting pedestrian fatalities at unsignalized crosswalks by means of statistical traffic data 被引量:4
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作者 Claudio Feliciani Andrea Gorrini +3 位作者 Luca Crociani Giuseppe Vizzari Katsuhiro Nishinari Stefania Bandini 《Journal of Traffic and Transportation Engineering(English Edition)》 CSCD 2020年第1期1-18,共18页
This work presents a simulation model for unsignalized crosswalks which takes into account collisions between vehicles and pedestrians,thus allowing to assess the estimated yearly pedestrian fatality.In particular,we ... This work presents a simulation model for unsignalized crosswalks which takes into account collisions between vehicles and pedestrians,thus allowing to assess the estimated yearly pedestrian fatality.In particular,we focus on a method to calibrate such a model combining measurable crosswalk characteristics,such as maximum speed limit or drivers’compliance,with statistical data for past accidents obtained from local municipality.In order to perform simulations under realistic conditions,we constructed a one-week scenario where pedestrian and vehicle traffic vary using specific patterns each hour of the week.The constructed traffic profile is based on openly available data and the suitability for the scenario considered(a crosswalk in Milan,Italy)is investigated showing that cultural/lifestyle elements determine the variation of weekly traffic.Simulations using the constructed one-week scenario were used to obtain the only non-measurable parameter which account for pedestrians’and drivers’distraction.In addition,we also focused on the presence of elderly pedestrians which have different physiological characteristics compared to adults or children and are becoming an important part of the population in several countries around the globe.The simulation model presented here and the method suggested for calibration may be employed in different contexts,thus allowing to build an important tool to be used not only for transportation efficiency/optimization but also for safety analysis. 展开更多
关键词 TRAFFIC simulation ACCIDENT prevention Unsignalized CROSSWALK Vehicle-pedestrian interaction WEEKLY TRAFFIC variation
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