检索结果-南通市图书馆

CHIRAL RING OF Sp(N) AND SO(N) SUPeRSYMMeTRIC GAUGe THeORY IN FOUR DIMeNSIONS

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2003年第4期24卷 403-414页

作者： e.WITTeN Institute for Advanced Study PrincetonNJ 08540USA

The chiral ring of classical supersymmetric Yang-Mills theory with gauge group Sp(N) or SO(N) is computed, extending previous work (of Cachazo, Douglas, Seiberg, and the author)for SU(N). The result is that, as has been conjectured, the ring is generated by the usualglueball superfield S ～ Tr WαWα, with the relation Sh = 0, h being the dual Coxeter *** this proposition has important implications for the behavior of the quantum theory,the statement and (for the most part) the proofs amount to assertions about Lie groups withno direct reference to gauge theory.

关键词： Chiral ring Gauge group Lie group Supersymmetric gauge theory

Formation of efficient dye-sensitized solar cells by introducing an interfacial layer of hierarchically ordered macro-mesoporous TiO_2 film

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2011年第6期54卷 930-935页

作者： HALPeRT Jonathan e State Key Laboratory of Multi-phase Complex Systems Institute of Process engineering Chinese Academy of Sciences

Hierarchically ordered macro-mesoporous TiO2 films (Ti-Ma-Me) were fabricated on fluorine-doped tin oxide (FTO) substrates through the confinement self-assembly method. The prepared Ti-Ma-Me possesses periodically ordered structure and a large specific surface area, which was applied as an interfacial layer between the nanocrystalline TiO2 film (P25-TiO2) and FTO electrode in the dye-sensitized solar cell (DSSC). The introduction of a Ti-Ma-Me interfacial layer increased the shortcircuit current density (Jsc) from 7.49 to 10.65 mA/cm2 and the open-circuit voltage (Voc) from 0.65 to 0.70 V as the result of its improved light harvesting efficiency by allowing for the high roughness factor and enhanced multiple internal reflection or scattering as well as reducing the back-transport reaction by blocking direct contact between the electrolyte and FTO electrode. Therefore, the photovoltaic conversion efficiency (η) was improved by 83% from 3.04% to 5.55%, as compared to a device using a bare P25 TiO2 photoanode.

关键词： dye-sensitized solar cells hierarchical ordered macro-mesoporous photoanode

Southeast Asian Perspectives on Nutrition Needs for the New Millennium

在线全文

学校读者我要写书评

暂无评论

Biomedical and environmental Sciences 2001年第1期14卷 75-81页

作者： e-SIONG Tee Head Division of Human Nutrition Institute for Medical Research

Over the last three decades, there has been significant changes in the lifestyles of communities, including food habits, and food purchasing and consumption patterns in the Southeast Asian region. As a result, there is a definite change in the food and nutrition issues in the region. Nutritional deficiencies in many of these countries are slowly being decreased in magnitude. On the other hand, the significant proportions of the population are now faced with the other facet of the malnutrition problem, namely diet related chronic diseases. However, because of the different stages of socio economic development, the extent of each of these extremes of the malnutrition problems varies considerably between the different countries in Southeast Asia. Nutrition needs in the new millennium would necessarily differ somewhat among these countries while at the same time, there would be a considerable amount of similarities. This presentation highlights several macro issues that countries in the region may focus on in the near future. Various intervention programmes have been undertaken by authorities to tackle the co existence of twin faces of malnutrition in many developing countries. It would be desirable to have a blue print of such programmes and activities in the National Plans of Action for Nutrition (NPANs). The NPAN should be more than a framework or a descriptive document. It should be a tool for action, an operational plan that sets out priorities; identifies projects and activities, with details of implementation such as what, how and when; designates responsibilities and accountability for the activities; identifies resource requirements and their source; and sets out the plan for monitoring and evaluation. One of the main obstacles in the formulation and effective implementation of intervention programmes in developing countries is the lack of comprehensive data on the extent of the problems in many cases and the causes of such problems specificy to the

关键词： developing countries nutritional status consumption patterns operational plan Southeast Asia Life Sciences food habits

Articulated dental cast analysis of asymptomatic and symptomatic populations

在线全文

学校读者我要写书评

暂无评论

International Journal of Oral Science 2016年第2期8卷 126-132页

作者： Frank e Cordray Department of Orthodontics College of Dentistry Ohio State University Columbus USA

Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement （DAD）, especially laterally, with symptoms, mandibular condyle displacement （CD） resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache （CMCH） and temporo-mandibular dysfunction （TMD）. The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position （SCP） and the intercuspal position （ICP） and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles （displaced most frequently inferior （down） and posterior （distal）） and substantially increased frequency and magnitude of displacement of the dental arches （with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes） in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint.

关键词： dental arch displacement condylar displacement seated condylar position intercuspal position musculo-skeletaldysfunction temporo-mandibular dysfunction common muscle contraction headache

Lepton electric Charge Swap at the 10 TeV energy Scale

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2013年第11期60卷 561-570页

作者： e. Koorambas 8A Chatzikosta 11521 Ampelokipi Athens Greece

We investigate the nature of the dark matter by proposing a mechanism for the breaking of local rotational symmetry between ordinary third family leptons and proposed non-regular leptons at energy scales below 10 TeV. This symmetry breaking mechanism involves electric charge swap between ordinary families of leptons can and produces highly massive non-regular leptons of order 0 （1 TeV） mass unobservable at energy scales below 10 TeV （the scale of LeP Ⅰ, Ⅱ and neutrino oscillation experiments）. electric charge swap between ordinary families of leptons produces heavy neutral non-regular leptons with order 0 （1 TeV） masses, which may form cold dark matter. The existence of these proposed leptons can be tested once the Large Hadron Collider （LHC） becomes operative at 10 TeV energy-scales. This proposition may have far reaching applications in astrophysics and cosmology.

关键词： conservation law in decays group theory Brane and extra dimensions

Role of erbB family receptor tyrosine kinases in intrahepatic cholangiocarcinoma

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2008年第46期14卷 7033-7058页

作者： Alphonse e Sirica Division of Cellular and Molecular Pathogenesis Department of PathologyVirginia Commonwealth University School of Medicine

Aberrant expression and signaling of epidermal growth factor receptor (erbB) family receptor tyrosine kinases, most notably that of erbB2 and erbB1, have been implicated in the molecular pathogenesis of intrahepatic cholangiocarcinoma. Constitutive overexpression of erbB2 and/or erbB1 in malignant cholangiocytes has raised interest in the possibility that agents which selectively target these receptors could potentially be effective in cholangiocarcinoma therapy. However, current experience with such erbB-directed therapies have at best produced only modest responses in patients with biliary tract cancers. This review provides a comprehensive and critical analysis of both preclinical and clinical studies aimed at assessing the role of altered erbB2 and/or erbB1 expression, genetic modifications, and dysregulated signaling on cholangiocarcinoma development and progression. Specific limitations in experimental approaches that have been used to assess human cholangiocarcinoma specimens for erbB2 and/or erbB1 overexpression and gene amplification are discussed. In addition, current rodent models of intrahepatic cholangiocarcinogenesis associated with constitutive erbB2 overexpression are reviewed. Select interactive relationships between erbB2 or erbB1 with other relevant molecular signaling pathways associated with intrahepatic cholangiocarcinoma development and progression are also detailed, including those linking erbB receptors to bile acid, cyclooxygenase-2,interleukin-6/gp130, transmembrane mucins, hepatocyte growth factor/Met, and vascular endothelial growth factor signaling. Lastly, various factors that can limit therapeutic efficacy of erbB-targeted agents against cholangiocarcinoma are considered.

关键词： Cholangiocarcinoma erbB activation Bile acids Cyclooxygenase-2 erbB targeted therapies

X Y Z particles at BABAR

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第6期34卷 644-649页

作者： e.Prencipe LAPP-Laboratoire de Annecy de Physique de Particules

This paper intends to shortly summarize the recent results on Spectroscopy, published from the BABAR Collaboration. The BABAR experiment is a B-factory, at SLAC, where asymmetric energy beams of electron-positron are accelerated and collide at the energy in the center of mass of T（4S）. In 9 years of data taking, BABAR had collected 433 fb^-1 equivalent luminosity on-peak-data at the T（4S） energy, 30 fb^-1 data at the T（3S） energy, 15 fb^-1 data at the T（2S） energy, and a scan around T（4S） was done, collecting 25 pb^-1 every 5 MeV. Thanks to the high luminosity achieved, it is possible to perform high precision measurements, and spectroscopy studies. An update on the measurement of the state X（3872） will be given, as final result published by using the whole dataset available. Then, a new preliminary Y（4260） measurement is reported, and the study of the invariant mass J/ψπ^＋π^- in ISR events is shown, where no evidence of the state Y（4050） is highlighted. As conclusion, the results on the angular distribution analysis performed on the state Z（4430） are reported.

关键词： spectroscopy charmonium BABAR

How Specific is Non-Hypersensitive Host and Nonhost Resistance of Barley to Rust and Mildew Fungi?

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2014年第2期13卷 244-254页

作者： Niks R e Laboratory of Plant Breeding Wageningen UniversityP.O.Box 3866700 AJ WageningenThe Netherlands

Full nonhost resistance can be defined as immunity, displayed by an entire plant species against all genotypes of a plant pathogen. Interesting biological questions are, whether the genes responsible for the nonhost status of a plant species have a general or a specific effectiveness to heterologous （＂nonhost＂） pathogens？ Is the nonhost resistance to pathogens of plant species that are related to the nonhost based on R-genes or on other types of genes？ We study this question in barley （Hordeum vulgare L.）, which is a near-nonhost to several rusts （Puccinia） of cereals and grasses. By crosses and selection we accumulated susceptibility and developed an experimental line, SusPtrit, with high susceptibility to at least nine different heterologous rust taxa such as the wheat and Agropyron leaf rusts （P. triticina and P. persistens, respectively）. At the microscopic level there is also some variation among barley accessions in the degree that the heterologous wheat powdery mildew （Blumeria graminis ***. tritici） is able to form haustoria in epidermal cells. So, also the genetics of the variation in level of nonhost resistance to heterologous mildew fungi can be studied in barley. Our data obtained on mapping populations involving three regular nonhost-immune accessions （Vada, Cebada Capa and Golden Promise） suggest that nonhost resistance is the joined effect of multiple, quantitative genes （QTLs） and very occasionally a major gene （R-gene？） is involved. Most QTLs have effect to only one or two heterologous rusts, but some have a wider spectrum. This was confirmed in a set of QTL-NILs. Those QTL-NILs are used to fine-map the effective genes. In some cases, a QTL region with effectiveness to several heterologous rusts might be a cluster of genes with a more narrow spectrum of effectiveness. Our evidence suggests that nonhost resistance in barley to rust and powdery mildew fungi of related Gramineae is not due to R-genes, but to pathogen species-specific quantitative resi

关键词： genetics specificity basal resistance

Sediment discharge of the Yellow River, China: past, present and future——A synthesis

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2015年第2期34卷 1-8页

作者： ReN Mei'e Key Laboratory of Coast and Island Development of Ministry of education School of Geographic and Oceanographic Sciences Nanjing University

The Yellow River cut through Sanmenxia Gorge and discharged into the sea via the North China Plain in 150 ka BP; since then, around 86 000 × 108 t sediment has been transported passing Sanmenxia Gorge. Based on land use and land cover changes in Loess Plateau and other available evidence, an estimate of the Yellow River sediment budget is presented here： about 72% of the sedimentary material was trapped in the North China Plain and the remainder（i.e., 26%） escaped to the sea. At the present stage, 〈 0.2×108 t/a suspended sediment of the Yellow River enter the northern Yellow Sea. The transport pattern is determined mainly by the shelf current system. Annually 0.2×108–0.3×108 t of suspended particles are carried to the east China Sea; the materials are derived mainly from coastal and subaqueous delta erosion associated with the abandoned Yellow River on the Jiangsu coast. Since 1972, the lower Yellow River started to have a situation of continuous no-flow. During 1996–2000, the annual water flow and sediment discharge are only 19%, as compared with normal years（i.e., average for 1950–1979）. In response to global warming and increase of water diversion from the Yellow River for industrial and urban use, the sediment flux of the Yellow River to the sea will most likely remain small in the next two to three decades.

关键词： Yellow River Loess Plateau sediment budget transport patterns sediment retention