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Scientific Analysis (scientific + analysis)
Selected AbstractsRough Terrain: Spatial Variation in Campaign Contributing and VolunteerismAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 1 2010Wendy K. Tam Cho We examine spatial patterns of mass political participation in the form of volunteering and donating to a major statewide election campaign. While these forms of participation are predictably associated with the political and socioeconomic characteristics of the precincts in which the participants reside, we find that these statistical relationships are spatially nonstationary. High-income neighborhoods, for example, are associated with stronger effects on participation at some locations more than at others. By using geographically weighted regression (GWR) to specify local regression parameters, we are able to capture the heterogeneity of contextual processes that generate the geographically uneven flow of volunteers and contributors into a political campaign. Since spatial nonstationarity may well be a rule rather than an exception in the study of many political phenomena, social scientific analyses should be mindful that relationships may vary by location. [source] The alcohol dehydrogenases of Saccharomyces cerevisiae: a comprehensive reviewFEMS YEAST RESEARCH, Issue 7 2008Olga De Smidt Abstract Alcohol dehydrogenases (ADHs) constitute a large family of enzymes responsible for the reversible oxidation of alcohols to aldehydes with the concomitant reduction of NAD+ or NADP+. These enzymes have been identified not only in yeasts, but also in several other eukaryotes and even prokaryotes. The ADHs of Saccharomyces cerevisiae have been studied intensively for over half a century. With the ever-evolving techniques available for scientific analysis and since the completion of the Yeast Genome Project, a vast amount of new information has been generated during the past 10 years. This review attempts to provide a brief summary of the wealth of knowledge gained from earlier studies as well as more recent work. Relevant aspects regarding the primary and secondary structure, kinetic characteristics, function and molecular regulation of the ADHs in S. cerevisiae are discussed in detail. A brief outlook also contemplates possible future research opportunities. [source] INVESTOR RELATIONS, LIQUIDITY, AND STOCK PRICESJOURNAL OF APPLIED CORPORATE FINANCE, Issue 4 2000Michael J. Brennan Although the first investor relations department was established by General Electric as long ago as 1952, the role of investor relations (IR) is one that has largely escaped scientific analysis and academic scrutiny. This article attempts to demonstrate the importance of a company's IR activities for its stock price by establishing a clear chain of causation between the following: 1,corporate IR activities and the number of stock analysts who follow the firm; 2,the number of analysts who follow the firm and the liquidity of trading in the firm's shares; 3,the liquidity of the firm's shares and its required rate of return, or cost of capital. The authors begin by presenting evidence that corporate IR activities, in the form of high levels of disclosure and presentations to investment analysts, increase the number of analysts who follow the firm by reducing their cost of acquiring information. Studies have also shown that more effective IR tends to improve the accuracy of analyst forecasts and the degree of agreement among analysts. Second, the authors summarize their own research showing that the number of analysts who follow a firm has a positive effect on the liquidity of the firm's shares. More specifically, their findings can be interpreted as saying that, for the average company, coverage by six additional analysts reduces "market-impact costs" (using a measure known as Kyle's lambda) by 28%, holding volume constant. And when the indirect effect of increased analyst coverage through expanded volume is taken into account, the reduction in trading costs is estimated to be as high as 85%. The final link in the chain of analysis is the growing evidence (much of it reviewed in the preceding article) that increased liquidity leads to a lower cost of capital and thus higher stock prices. In sum, a firm can reduce its cost of capital and increase its stock price through more effective investor relations activities, which reduce the cost of information to the market and to investment analysts in particular. [source] Machine invention, innovation, and elementary steps,ADVANCES IN POLYMER TECHNOLOGY, Issue 2 2002Zehev Tadmor The systematic scientific analysis of polymer processing machines leads to the definition of a small number of elementary steps, which in chemical engineering terminology are the "unit operations" of these machines that transcend individual machine configuration and reflect the common experience of the processed material in any type of machine. The elementary steps reveal the detailed specific physical mechanisms that take place in these machines. These mechanisms, in turn, are powerful tools for triggering machine innovation and invention. The proposed methodology consists of two steps: first via the scientific analysis the process is repeatedly decomposed into its constituent elements and then the elements are recombined or reconstructed in a systematic way into either innovative solutions or novel inventions. The methodology, is demonstrated by three case studies. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 87,97, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10018 [source] The Lindisfarne Gospels and two other 8th century Anglo-Saxon/Insular manuscripts: pigment identification by Raman microscopyJOURNAL OF RAMAN SPECTROSCOPY, Issue 1 2004Katherine L. Brown Abstract The Lindisfarne Gospels (Cotton MS Nero D iv, ca. 715 AD) and two nearly contemporary manuscripts (Royal MS 1B vii and Add. MS 40618) held in the British Library have been analysed in detail by Raman microscopy in order to establish the palette of each. The blue pigment used on the Lindisfarne Gospels is shown not to be lazurite, as concluded in 1960 by visual examination of known pigments and those on the Gospels, but exclusively indigo. Of the Anglo-Saxon and Insular manuscripts studied so far by Raman microscopy, the earliest found to include lazurite in its palette is Add. MS 40618, not on its still extant original miniature of ca. 756 AD, but on later additions of ca. 920 AD. The Insular triumvirate palette, which had been assumed to consist of orpiment, red lead and verdigris, was found also to include red ochre and vergaut (indigo admixed with orpiment) but not necessarily verdigris. The palettes of the manuscripts studied, as specified in existing literary sources, are not reliable, and careful in situ scientific analysis of the pigments present is essential to establish the identity of the latter and of any decomposition products present. Copyright © 2004 John Wiley & Sons, Ltd. [source] MARBLE PROVENANCE INVESTIGATION OF ROMAN SARCOPHAGI FROM THESSALONIKI*ARCHAEOMETRY, Issue 1 2010Y. MANIATIS The provenance question of the marbles used for making the sarcophagi of local production of Thessaloniki in the Roman period had been posed by archaeologists in the past. The hypothesis was that the material came mainly from the quarries of Thassos Island. This paper presents the scientific analysis of 23 characteristic samples from selected sarcophagi at the Museum of Thessaloniki, using three different techniques: electron paramagnetic resonance (EPR) spectroscopy, stable isotope analysis and maximum grain size measurements, plus in-situ examination. New combinations of parameters were used in order to resolve fully the provenance of all samples. The results showed that the vast majority of the objects were indeed made in Thassian marble but from three different quarries, namely Vathy/Saliara (dolomitic marble), Aliki (calcitic marble) and Acropolis/Phanari (calcitic marble). The calcitic marbles from Aliki and to a lesser degree from Acropolis/Phanari are met in all the basic types of sarcophagi (framed type, plain type, garland sarcophagi). The use of the better quality and snow-white dolomitic marble from Vathy/Saliara quarries is relatively restricted and is often found in works that are above the average regarding the quality of their workmanship. In addition, two sarcophagi were made in Pentlelic marble and one in Proconnesian. The scientific analysis results provide a good confirmation of the archaeological estimates and, furthermore, the conclusions constitute henceforth a secure basis for the study of the entire sculptured works of Thessaloniki. [source] The Biomolecular Crystallization Database Version 4: expanded content and new featuresACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2009Michael Tung The Biological Macromolecular Crystallization Database (BMCD) has been a publicly available resource since 1988, providing a curated archive of information on crystal growth for proteins and other biological macromolecules. The BMCD content has recently been expanded to include 14,372 crystal entries. The resource continues to be freely available at http://xpdb.nist.gov:8060/BMCD4. In addition, the software has been adapted to support the Java-based Lucene query language, enabling detailed searching over specific parameters, and explicit search of parameter ranges is offered for five numeric variables. Extensive tools have been developed for import and handling of data from the RCSB Protein Data Bank. The updated BMCD is called version 4.02 or BMCD4. BMCD4 entries have been expanded to include macromolecule sequence, enabling more elaborate analysis of relations among protein properties, crystal-growth conditions and the geometric and diffraction properties of the crystals. The BMCD version 4.02 contains greatly expanded content and enhanced search capabilities to facilitate scientific analysis and design of crystal-growth strategies. [source] Local helioseismology in the SDO HMI/AIA data analysis pipelineASTRONOMISCHE NACHRICHTEN, Issue 3-4 2007R. S. Bogart Abstract Local helioseismology techniques will play a principal role in the pipeline processing of data from HMI to produce standard data products suitable for scientific analysis. Many of these techniques are undergoing rapid development, and it is expected that new or enhanced algorithms and models will be contributed by members of the community. We describe the design and implementation of the data analysis environment of the SDO Joint Science Operations Center for the benefit of potential contributors and users. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Phylogenetics and Ecology: As Many Characters as Possible Should Be Included in the Cladistic Analysis,CLADISTICS, Issue 1 2001Philippe Grandcolas As many data as possible must be included in any scientific analysis, provided that they follow the logical principles on which this analysis is based. Phylogenetic analysis is based on the basic principle of evolution, i.e., descent with modification. Consequently, ecological characters or any other nontraditional characters must be included in phylogenetic analyses, provided that they can plausibly be postulated heritable. The claim of Zrzavý (1997, Oikos 80, 186,192) or Luckow and Bruneau (1997, Cladistics 13, 145,151) that any character of interest should be included in the analysis is thus inaccurate. Many characters, broadly defined or extrinsic (such as distribution areas), cannot be considered as actually heritable. It is argued that we should better care for the precise definition and properties of characters of interest than decide a priori to include them in any case in the analysis. The symmetrical claim of de Queiroz (1996, Am. Nat. 148, 700,708) that some characters of interest should better be excluded from analyses to reconstruct their history is similarly inaccurate. If they match the logical principles of phylogenetic analysis, there is no acceptable reason to exclude them. The different statistical testing strategies of Zrzavý (1997) and de Queiroz (1996) aimed at justifying inclusion versus exclusion of characters are ill-conceived, leading respectively to Type II and Type I errors. It is argued that phylogenetic analyses should not be constrained by testing strategies that are downstream of the logical principles of phylogenetics. Excluding characters and mapping them on an independent phylogeny produces a particular and suboptimal kind of secondary homology, the use of which can be justified only for preliminary studies dealing with broadly defined characters. [source] | ||||||||||||||||