1,721,004 research outputs found
Talk by Prof To Cho-Yee (25 Feb 1983)
No full textProf. To Cho-Yee (Director, School of Education, Chinese University of Hong Kong) delivering his talk entitled "The Teaching of the Chinese Language in Hong Kong"
The growth of public sector in Hong Kong.
Full text linkby Cho Yee Fun, Yvonne.Thesis (M.Phil.)--Chinese University of Hong Kong, 1989.Bibliography: leaves 123-127
Simvastatin suppresses self-renewal of mouse embryonic stem cells by inhibiting RhoA geranylgeranylation
No full textStatins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, were originally developed to lower cholesterol. Their pleiotropic (or cholesterol-independent) effects at the cellular and molecular levels are highly related to numerous cellular functions, such as proliferation and differentiation. However, they are hardly studied in embryonic stem cells. In this study, we evaluated the effects of statins on mouse ESCs (J1, D3, and RW.4) to enhance our understanding of the molecular basis of ESC self-renewal. Treatment of ESCs with simvastatin, mevastatin, atorvastatin, or pravastatin induced morphological change and decreased cell proliferation. We observed that the use of simvastatin was most effective in all three ESCs. Loss of ESC self-renewal by simvastatin was determined by marked downregulation of ESC markers alkaline phosphatase, Oct4, Nanog, Rex-1, and SSEA-1. Simvastatin effects were selectively reversed by either rnevalonate or its metabolite geranylgeranyl pyro-phosphate (GGPP) but not by cholesterol or farnesyl pyrophosphate. These results suggest that simvastatin effects were mainly derived from depletion of intracellular pools of GGPP, the substrate required for the geranylgeranylation. Using this approach, we found that GGPP, a derivative of the rnevalonate pathway, is critical for ESC self-renewal. Furthermore, we identified that simvastatin selectively blocked cytosol-to-membrane translocalization of RhoA small guanosine triphosphate-binding protein, known to be the major target for geranylgeranylation, and lowered the levels of Rho-kinase (ROCK)2 protein in ESCs. In addition, simvastatin downregulated the ROCK activity, and this effect was reversed by addition of GGPP. Our data suggest that sirnvastatin, independently of its cholesterol-lowering properties, impairs the ESC self-renewal by modulating RhoA/ROCK-dependent cell-signaling
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Patent Technology Clustering Based on Their Classification and the Classification Schedule
No full text專利文件中之每一專利分類號，均代表著一個明確的技術領域分類代碼，本研究取用美國專利文件作為研究對象，並以美國專利分類號作為每篇專利文件之代表特徵，並利用該特徵值，將技術相似性高的專利叢集起來，以建立專利技術叢集。而每篇美國專利文件均具有一到多個美國專利分類號，因此每篇專利都可能具有多面向的技術觀點，可以一特徵值序列表示之。國專利分類號體系是由多個階層式分類架構所組成，每個架構均代表一主要技術領域的集合體，專利技術叢集的法則，即在於以各專利文件所屬的分類號特徵值序列，來計算專利文件間之技術相似度，相似度的算法可單純考量分類號特徵在相同分類號階層架構裡的概念距離遠近而得，或是再納入另一考量因子，即隸屬相異分類號架構底下的分類號間的共篇程度來決定；至於技術叢集的方法，採用兩階段叢集法則，第一階段利用階層式叢集法，獲得適當的叢集數，第二階段再利用非階層式叢集法，獲得每一叢集的所屬專利技術內容。後，以實際的案例分析，來探討不同的專利相似度計算考量因子，對於不同的專利技術特徵組成性質，是否會造成差異性的叢集結果。Each classification code in the patent document represents a definite technical domain, this thesis took U.S. patent as research source and selected U.S. patent classification (USPC) code as the feature to represent a patent. According to those features, the technology cluster could be formed by the high similar patents. Each U.S. patent may have one or multiple technical viewpoints due to its amounts of USPC code, it can be represented by a feature list. U.S. classification system is composed by many USPC schedules, each USPC schedule represent a set of technical domain. he objective technology cluster was formed by the feature list similarities of patents, and the similarities could be measured by two factors, one was only considering the conceptual distance between two USPC codes under the same USPC schedule, another was considering the pair coupled rate of two USPC codes under different USPC schedules in addition. This thesis used two stage clustering algorithm to get the technology cluster, the first stage used hierarchical clustering algorithm to determine the number of clusters, the second stage used non-hierarchical clustering algorithm to get the members of each cluster.inally, in cases study, discussed whether different patent similarity measures, could result to different technology clusters or not.Chapter 1 Introduction 1.1 Background 1.2 Related works and Literature Review 1.3 Characteristic of Patent Document 7.4 Motivation 9.5 Research Objective 10hapter 2 Patent Characteristics By USPC 11.1 Feature Representation for a Patent 11.2 Nomenclature of USPC Schedule 11.3 Hierarchical Relationship of USPC Schedule 122.4 The Feature Composition Index for Patents 14hapter 3 Association between USPC under the Same Main Class16 3.1 Research Procedure 16.2 USPC Distance under the Same Classification Schedule 17.3 Distance between Classifications under the Same Main Class 17.4 Patent Similarity 23hapter 4 Association between USPC under Different Main Classes 254.1 Research Procedure 25.2 Pair Coupled Rate between USPC under Different Main classes 26.3 USPC Distance from the Pair Coupled Rate 26hapter 5 Patent Clustering 28 5.1 Clustering Method 28.3 The Measure of Patent Clustering Result 30hapter 6 Case Study: OLED 31.1 Clustering Analysis without Similarity between Different USPC Schedules 35.2 Clustering Analysis with Similarity between Different USPC Schedules 38.3 Discussion the Difference of Result between Two Analyses 40hapter 7 Case Study: Dexterous Hand of Robot 42.1 Clustering Analysis without Similarity between Different USPC Schedules 45.2 Clustering Analysis with Similarity between Different USPC Schedules 47.3 Discussion the Difference of Result between Two Analyses 50hapter 8 Conclusions 52eferences 5
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
