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Different Performances (different + performance)
Selected AbstractsGood practice in head and neck fine needle aspiration cytology as assessed by CUSUMCYTOPATHOLOGY, Issue 6 2002I. A. Robinson Providing data as evidence of good practice is becoming imperative to meet the demands of professional revalidation and clinical governance. Sensitivity and specificity are common performance measures in fine needle aspiration (FNA) but are vulnerable to discordant analytical methods. We introduce a CUSUM technique and show how it may be used to show attainment and maintenance of proficiency in head and neck (H&N) FNA. In addition, we show how it can be used to compare practices and demonstrate different performance for FNAs from different tissues; a fact that must be recognized by anyone devising minimum performance values. [source] Is there a Difference?JOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 1-2 2007The Performance Characteristics of SRI Equity Indices Abstract:, This study analyses whether stock indices that represent socially responsible investments (SRI) exhibit a different performance compared to conventional benchmark indices. In contrast to other studies, the analysis concentrates on SRI indices and not on investment funds. This has several advantages, since transaction costs of funds, the timing activities and the skill of the fund management do not have to be considered. A direct measure of the performance effects of SRI screens is therefore examined. The 29 SRI stock indices are analysed by single-equation models as well as by multi-equation systems that exploit the information in the cross-section. SRI stock indices do not exhibit a different level of risk-adjusted return than conventional benchmarks. But many SRI indices have a higher risk relative to the benchmarks. The findings are robust to the use of different benchmark indices and apply to all common types of SRI screening. [source] Performance of DFT in modeling electronic and structural properties of cobalaminsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 12 2006Jadwiga Kuta Abstract Computational modeling of the enzymatic activity of B12 -dependent enzymes requires a detailed understanding of the factors that influence the strength of the CoC bond and the limits associated with a particular level of theory. To address this issue, a systematic analysis of the electronic and structural properties of coenzyme B12 models has been performed to establish the performance of three different functionals including B3LYP, BP86, and revPBE. In particular the cobalt,carbon bond dissociation energies, axial bond lengths, and selected stretching frequencies have been analyzed in detail. Current analysis shows that widely used B3LYP functional significantly underestimates the strength of the CoC bond while the nonhybrid BP86 functional produces very consistent results in comparison to experimental data. To explain such different performance of these functionals molecular orbital analysis associated with axial bonds has been performed to show differences in axial bonding provided by hybrid and nonhybrid functionals. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 1429,1437, 2006 [source] Discrete versus In Situ -Generated Aluminum-Salen Catalysts in Enantioselective Cyanosilylation of Ketones: Role of Achiral LigandsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 5 2008Ali Alaaeddine Abstract The monometallic species {Salen}AlX (X=Me, 2a,b; X=Cl, 4a,b; O- i- Pr, 5a,b) and open bimetallic species {Salen}[AlMe2]2 (3a,b) that result from binary combinations between an aluminum precursor [trimethylaluminum, dimethylaluminum chloride, aluminum tris(isopropoxide)] and a diprotio {Salen}H2 pro-ligand 1a,b (a=1R,2R -cyclohexyl-salen; b=1R,2R -diphenylethylene-salen) have been isolated. The crystal structures of 3b, 4b and of ,-oxo species [{diphenylethylene-salen}Al]2O (6b) are reported. The discrete species 2,5a,b have been individually evaluated in the asymmetric cyanosilylation of acetophenone. It is shown that, in several cases, these discrete catalysts display dramatically different performances than the catalyst systems in situ -generated from the binary combinations. The influence of the achiral ligand X on both the enantioselectivity and activity of the cyanosilylation reaction has been investigated, resulting in the definition of a highly active and productive hexafluoro-2-propoxide-based catalyst for a variety of aryl alkyl ketones (TON up to 470, TOF up to 140,h,1 at ,20,°C for acetophenone). [source] Contrast analysis of the composition of ribosomes extracted with different purification proceduresJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2000Giuseppe Briganti The composition and hydration of E. coli ribosomes isolated with different purification protocols has been analysed by combining two experimental techniques: measurements of small-angle neutron scattering (SANS), for two different isotopic solvent compositions, and refractive index (RI) increments. From the contrast between the solvent and solute scattering densities and the molar polarizability, determined experimentally with SANS and RI measurements, three independent equations are obtained and three unknown quantities are determined: (i) the volume of the solute hydrated skeleton Vs, (ii) the material contained in it, namely the biological components, intrinsic (rRNA and proteins) and extrinsic, such as aminoacylsynthetase and elongation factors, (iii) the number of water molecules structurally bound to the ribosome and non-exchangeable with the solvent. From the form factor at infinite contrast, a second definition of the solute volume is obtained, , which represents the volume within the contour surface of the ribosome. This value is generally larger than Vs and can include a certain amount of water molecules, i.e. those inside the volume (,Vs). Considering the molar volume of this water to be equal to that of the bulk water, it is possible to evaluate its amount. The particle density calculated from the ribosome components in , including proteins, RNA, bound and unbound water molecules, corresponds to the buoyant density measured for E. coli 70S particles. The two ribosomal preparations display different performances in protein synthesis; hence the results indicate that the optimal condition corresponds to a wider skeleton and contour volume but containing a smaller amount of segregated water molecules. It is believed that the method provides a reliable technique to determine the composition of ribosomes under various experimental conditions. [source] Diet segregation between two sympatric ,small'Barbus spp: an experimental study of mechanismsJOURNAL OF FISH BIOLOGY, Issue 2003E. Dejen Gut contents of two co-occurring species of ,small' diploid barbs (<10 LF cm) in Lake Tana revealed that zooplankton is the major diet component for B. tanapelagius(75% based on volume), but less prominent in B. humilis(40%). Functional response experiments in the laboratory were conducted to elucidate the mechanisms causing this difference. The type of functional response by the two ,small' barbs under different microcrustacean zooplankton densities (10, 20, 40, 60 and 80 ind.l,1) was examined. The functional response of B. tanapelagius to increasing prey densities corroborates with Holling Type II model, whereas B. humilis exhibits a Type III functional response. Predation rate is higher for B. tanapelagius at low zooplankton density (<40 ind.l,1) and equals the level of B. humilis at higher densities (>40 ind.l,1). This suggests that at lower zooplankton densities B. humilis is a less efficient forager on zooplankton prey items than B. tanapelagius. In Lake Tana average zooplankton density is relatively low (<35 ind.l,1). Under these food conditions, B. humilis is forced to feed on other food items (e.g. benthic invertebrates), whereas B. tanapelagius primarily feeds on zooplankton. The feeding potentials of the two ,small' barbs, as deduced from their morphology explain their different performances and their segregation in space and food resources. [source] RELIABILITY OF SENSORY ASSESSORS: ISSUES OF COMPLEXITYJOURNAL OF SENSORY STUDIES, Issue 1 2009JANNA BITNES ABSTRACT The objective of this study was to investigate whether the sensory performance of assessors in a sensory panel maybe explained by complexity of evaluated product. We aimed to investigate whether we could observe a decline in sensory performance when increasing the complexity of the product. The products increased in number of constituents from mixtures of sucrose, sodium chloride, citric acid and caffeine in water, to the foods ice tea and tomato soup constituting different levels of the same substances. Candidates who succeeded evaluating one product were not always successful evaluating others. Few subjects were successful in everything. The conclusion was that there is only minor systematic decline with increasing complexity of products. The authors emphasize that definition of complexity involves more than just counting number of constituents and taste sensations, and suggest that minor differences in the task given to the assessor might explain different performances. PRACTICAL APPLICATIONS Practical use of the research presented in the present paper is in a sensory evaluation context. It is important for the users of sensory data to find out how the profiling should be organized to achieve optimum output, and in specific, the need for extensive training when dealing with a more complex product. The present study hypothesized that sensory assessors would have more difficulties evaluating a more complex product. However, the results showed that panel leaders should be more concerned with the task variables in the sensory evaluation. Even a minor shift in task variables had a stronger impact on the performance and reliability of the assessors than increasing number of constituents and/or stimuli sensations of the product. This study did not demonstrate a need for extensive training when dealing with a more complex product as hypothesized. [source] Performance, Grouping and Schenkerian Alternative Readings in Some Passages from Beethoven's,Lebewohl' SonataMUSIC ANALYSIS, Issue 1 2008Alan Dodson ABSTRACT It is proposed that one musically interesting way to characterise and compare different performances or recordings of the same piece is by correlating them with different Schenkerian interpretations through the medium of grouping. This approach is demonstrated through an examination of four ,either/or' passages from the first movement of Beethoven's Piano Sonata in E Major, Op. 81a, passages in which at least two Schenkerian interpretations are possible. Schenker's own published and unpublished sketches, among others, are considered alongside recordings by Vladimir Ashkenazy, Emil Gilels, Richard Goode, Murray Perahia and Artur Rubinstein. The approach is not meant to be self-sufficient, but rather to contribute a new set of tools to the emerging multidisciplinary field of performance studies. [source] THE SOCIAL EFFICIENCY OF INSTRUMENTS FOR THE PROMOTION OF RENEWABLE ENERGIES IN THE LIBERALISED POWER INDUSTRYANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 3 2006Dominique Finon ABSTRACT,:,This paper compares the social efficiency of the two main regulatory instruments used to promote renewable energy sources in electricity generation (RES-E), taking into consideration their role in promoting the preservation of the climate. They are based on a purchase obligation and act either by price (feed-in tariffs) or by quantity (RES-E quotas). In their reference design, the instruments show different performances in several dimensions: market incentives intensity, control of the cost for consumers, safeguards of RES-E investments, and conformity with the new market regime of the electricity industry. The comparison shows that neither instrument offers an optimal solution in each of these dimensions. In particular, the intrinsic qualities of the quotas instrument that are put forward to mandate its adoption by the EU members are overestimated. A government will thus select an instrument in accordance with the relative importance of its objectives: environmental policy versus cost control by market pressure. [source] Catalysis in polymeric membrane reactors: the membrane roleASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2010M.G. Buonomenna Abstract Polymeric catalytic membrane reactors (PCMRs) combine a polymeric membrane that controls transfers and a catalyst that provides conversion. This review focuses on the polymeric membrane. Depending on the application, the micro-environment of the catalyst in the PCMR may be quite different from that existing in conventional reactors. This could originate different performances of the catalyst properties compared to its use without membrane. In some cases, catalysts for use in PCMR might require a specific design. In particular, the study of PCMR is a multidisciplinary activity, including material science, chemistry, and chemical engineering. Membrane based reactive separation processes, which combine two distinct functions, i.e. reaction and separation, have been around as a concept since the early stages of the membrane field itself, but have only attracted substantial technical interest during the last decade or so. Liquid phase catalytic oxidations are involved in numerous industrial processes ranging from fine to bulk chemical synthesis. PCMR polymeric membranes may also play a significant role in this field. 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