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General Methods (general + methods)
Selected AbstractsMild and General Methods for the Palladium-Catalyzed Cyanation of Aryl and Heteroaryl Chlorides.CHEMINFORM, Issue 35 2007Adam Littke Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Generalized treatment of NMR spectra for rapid chemical reactionsCONCEPTS IN MAGNETIC RESONANCE, Issue 4 2007Matthew D. Christianson Abstract Application of NMR spectroscopy to fast irreversible reactions (t1/2 < 0.7 s) has been hampered by limitations in instrumentation and general methods for modeling the complicated spectra that result. Analytical descriptions of nuclear spin dynamics during fast reactions, first solved by Ernst and coworkers, are limited to first-order reaction kinetics. We demonstrate that numeric methods enable simulation of NMR spectra for fast reactions having any form of rate law. Simulated stopped-flow NMR spectra are presented for a variety of common kinetic scenarios including reversible and irreversible reactions of first and second-order, multistep reactions, and catalytic transformations. The simulations demonstrate that a wealth of mechanistic information, including reaction rates, rate laws, and the existence of intermediates, is imbedded in a single NMR spectrum. The sensitivity of modern NMR instrumentation along with robust methods for simulating and fitting kinetic parameters of fast reactions make stopped-flow NMR an attractive method for kinetic studies of fast chemical reactions. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 165,183, 2007. [source] Study of corrosion resistance improvement by metallic coating for overhead transmission line conductorELECTRICAL ENGINEERING IN JAPAN, Issue 1 2008Masanori Isozaki Abstract Applying anticorrosion grease and aluminum-clad steel (AC) wires to ACSR have been adopted as general methods to protect overhead transmission line conductors and/or wires from corrosion. However, in some cases those means have been found to be ineffective on some transmission lines passing through acid atmosphere in the vicinity of a factory exhausting acid smoke. The corrosion caused by acid atmosphere is characterized by a higher speed in its progress as is well known. As means against such acid corrosion, application of high-purity aluminum, selective removal of intermetallic compound in aluminum, and plastic coating wires have been reported before, and each has both advantages and disadvantages. In a former report, we found that a new type of anticorrosion grease shows an excellent property against acid atmosphere as well as in a salty condition. Here we present a new type of anticorrosion technology of applying high-corrosion-resistance aluminum alloy or zinc coatings on each component wire of a conductor that we succeeded in developing through a serial study of anticorrosion methods on overhead transmission lines. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(1): 41,47, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20365 [source] Skeletal Estimation and Identification in American and East European Populations,JOURNAL OF FORENSIC SCIENCES, Issue 3 2008Erin H. Kimmerle Ph.D. Abstract:, Forensic science is a fundamental transitional justice issue as it is imperative for providing physical evidence of crimes committed and a framework for interpreting evidence and prosecuting violations to International Humanitarian Law (IHL). The evaluation of evidence presented in IHL trials and the outcomes various rulings by such courts have in regard to the accuracy or validity of methods applied in future investigations is necessary to ensure scientific quality. Accounting for biological and statistical variation in the methods applied across populations and the ways in which such evidence is used in varying judicial systems is important because of the increasing amount of international forensic casework being done globally. Population variation or the perceived effect of such variation on the accuracy and reliability of methods is important as it may alter trial outcomes, and debates about the scientific basis for human variation are now making their way into international courtrooms. Anthropological data on population size (i.e., the minimum number of individuals in a grave), demographic structure (i.e., the age and sex distribution of victims), individual methods applied for identification, and general methods of excavation and trauma analysis have provided key evidence in cases of IHL. More generally, the question of population variation and the applicability of demographic methods for estimating individual and population variables is important for American and International casework in the face of regional population variation, immigrant populations, ethnic diversity, and secular changes. The reliability of various skeletal aging methods has been questioned in trials prosecuted by the International Criminal Tribunal for the Former Yugoslavia (ICTY) in The Prosecutor of the Tribunal against Radislav Krsti, (Case No. IT-98-33, Trial Judgment) and again in the currently ongoing trial of The Prosecutor of the Tribunal against Zdravko Tolimir, Radivolje Mileti,, Milan Gvero, Vinko Pandurevi,, Ljubisa Beara, Vujadin Popovi,, Drago Nikoli,, Milorad Trbi,, Ljubomir Borovcanin (IT-05-88-PT, Second Amended Indictment). Following the trial of General Krsti,, a collaborative research project was developed between the Forensic Anthropology Center at The University of Tennessee (UT) and the United Nations, International Criminal Tribunal for the Former Yugoslavia, Office of the Prosecutor (ICTY). The purpose of that collaboration was to investigate methods used for the demographic analysis of forensic evidence and where appropriate to recalibrate methods for individual estimation of age, sex, and stature for specific use in the regions of the former Yugoslavia. The question of "local standards" and challenges to the reliability of current anthropological methods for biological profiling in international trials of IHL, as well as the performance of such methods to meet the evidentiary standards used by international tribunals is investigated. Anthropological methods for estimating demographic parameters are reviewed. An overview of the ICTY-UT collaboration for research aimed at addressing specific legal issues is discussed and sample reliability for Balkan aging research is tested. The methods currently used throughout the Balkans are discussed and estimated demographic parameters obtained through medico-legal death investigations are compared with identified cases. Based on this investigation, recommendations for improving international protocols for evidence collection, presentation, and research are outlined. [source] The effects of foreign direct investment on domestic firmsTHE ECONOMICS OF TRANSITION, Issue 3 2001Evidence from firm-level panel data in emerging economies This paper uses firm-level panel data to investigate empirically the effects of foreign direct investment on the productivity performance of domestic firms in three emerging economies of Central and Eastern Europe: Bulgaria, Romania and Poland. To this end, a unique firm-level panel dataset is used with detailed information on foreign ownership at the firm level. Two main questions are addressed in the present paper: (1) do foreign firms perform better than their domestic counterparts? (2) do foreign firms generate spillovers to domestic firms? The estimation technique in this paper takes potential endogeneity of ownership, spillovers and other factors into account by estimating a fixed effects model using instrumental variables in the general methods of moment technique for panel data. Only in Poland, do foreign firms perform better than firms without foreign participation. Moreover, for all three countries studied here, I find no evidence of positive spillovers to domestic firms, on average. In contrast, on average, there are negative spillovers to domestic firms in Bulgaria and Romania, while there are no spillovers to domestic firms in Poland. This suggests a negative competition effect that dominates a positive technology effect. JEL classification: D24, F14, O52, P31. [source] Extreme value analysis in biometricsBIOMETRICAL JOURNAL, Issue 2 2009Jürg Hüsler Abstract We review some approaches of extreme value analysis in the context of biometrical applications. The classical extreme value analysis is based on iid random variables. Two different general methods are applied, which will be discussed together with biometrical examples. Different estimation, testing, goodness-of-fit procedures for applications are discussed. Furthermore, some non-classical situations are considered where the data are possibly dependent, where a non-stationary behavior is observed in the data or where the observations are not univariate. A few open problems are also stated. [source] Floristic changes in the British Isles: comparison of techniques for assessing changes in frequency of plants with timeBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2006TIM C. G. RICH Botanical recording data are often used to assess changes in the frequencies of plant species over time, but are subject to marked variations in recording activity. We compare and evaluate some general methods that can be used to detect changes in species' frequencies taking into account the recording variations. Models for 15 species that have been studied in detail previously were compared using the numbers of individual records, sites, hectads, or vice-counties at different time scales (year, decade, moving averages, and pre-/post- specific dates), with or without correction for recording variation. The best methods had a correction for the amount of recording over time, summarized records by decade or moving average, and used an extrapolation between first and last records for sites or hectads. Increasing the geographical and temporal scales can decrease the influence of recording variations, but leads to a loss of sensitivity and under-estimates the true extent of change. The choice between sites and hectads will depend on the detail of the records available; cruder data sets should use the latter. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 152, 279,301. [source] | ||||||||||