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Reduction Approach (reduction + approach)
Selected AbstractsCardiovascular drugs as antidiabetic agents: evidence for the prevention of type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 7 2008D. P. Macfarlane Given the long-term health consequences and increasing incidence of type 2 diabetes, there is great interest to potentially prevent or delay its onset. Primary prevention studies have demonstrated that intensive exercise and weight reduction, and to a lesser extent certain antidiabetic agents, can reduce new onset diabetes in at-risk individuals. Results from post hoc analyses and secondary end-point outcomes of large randomized controlled trials of cardiovascular drugs suggest that these may also have beneficial effects, reducing the incidence of new onset diabetes in addition to their proven cardiovascular benefits. Multiple meta-analyses confirm that drugs primarily acting on the renin,angiotensin system (RAS) reduce the incidence of diabetes in the populations studied, perhaps via improved insulin sensitivity and/or effects on pancreatic beta cells. However, results from the recent Diabetes REduction Approaches with Medication study specifically failed to show a significant reduction in the incidence of diabetes with ramipril in individuals with abnormal glucose tolerance at baseline. There is only limited evidence that statins improve glucose tolerance, and although beta-blockers tend to have detrimental effects on glucose tolerance, newer agents with vasodilatory properties may confer benefits. With current guidelines, the use of cardiovascular drugs modifying the RAS will increase in at-risk individuals, but at present, they cannot be recommended to prevent diabetes. [source] Two-level multiscale enrichment methodology for modeling of heterogeneous platesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 9 2009Caglar OskayArticle first published online: 15 JUN 200 Abstract A new two-level multiscale enrichment methodology for analysis of heterogeneous plates is presented. The enrichments are applied in the displacement and strain levels: the displacement field of a Reissner,Mindlin plate is enriched using the multiscale enrichment functions based on the partition of unity principle; the strain field is enriched using the mathematical homogenization theory. The proposed methodology is implemented for linear and failure analysis of brittle heterogeneous plates. The eigendeformation-based model reduction approach is employed to efficiently evaluate the non-linear processes in case of failure. The capabilities of the proposed methodology are verified against direct three-dimensional finite element models with full resolution of the microstructure. Copyright © 2009 John Wiley & Sons, Ltd. [source] Single Nucleotide-Catalyzed Biomimetic Reductive AminationADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Atul Kumar Abstract We have successfully developed a single nucleotide (adenosine 5,-diphosphate)-catalyzed enantioselective direct reductive amination of aldehydes and ketones using a Hantzsch ester as reducing agent. The process is a simple, efficient and a real mimic of the NADH reduction approach for the synthesis of structurally diverse amines. This reaction is the first report demonstrating the ability of a single nucleotide as catalyst and one of the most genuine biomimetic reactions of organic chemistry. [source] Goal attainment for multiple cardiovascular risk factors in community-based clinical practice (a Canadian experience)JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 1 2009Pendar Farahani MD MSc Abstract Background, The primary goal in the clinical management of atherosclerotic cardiovascular (CV) disease is to reduce major CV risk factors. A single risk factor approach has been traditionally used for demonstrating effectiveness of therapeutic interventions designed to reduce CV risk in clinical trials, but a global CV risk reduction approach should be adopted when assessing effectiveness in the clinical practice setting. Objectives, To explore combined goal achievement for low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose and systolic-diastolic blood pressure, in patients with dyslipidemia on pharmacotherapy in community-based clinical practices across Canada. Methods, In a cross-sectional study, patients filling a prescription for any antihyperlipidemia therapy in selected pharmacies in Ontario, Quebec, British Columbia and Nova Scotia were recruited. Family physicians of the participating patients were requested to provide information from the patient's medical record. Ten-year CV risk was identified for each patient according to the Framingham criteria. Results, High-risk patients comprised 52% of the patient population; 34% were moderate-risk and 14% were low-risk. Patients had a mean of 2.8 CV risk factors; high-risk 3.7, moderate-risk 2.3 and low-risk 1.2. LDL-C goal attainment was observed in 62%, 79% and 96% of patients in high-risk, moderate-risk and low-risk strata respectively. BP goal was achieved in high-risk patients 58%, moderate-risk 83% and low-risk 95%. Glucose levels were below the threshold in 91% of patients. Complete global CV risk reduction was achieved in only 21%, 66% and 92% of high-risk, moderate-risk and low-risk strata respectively. Conclusion, This study illustrates that many patients with dyslipidemia in the Canadian population, and in particular the high-risk patients, did not meet the therapeutic targets for specific CV risk factors according to the Canadian guidelines. Overall, 54% of patients failed to achieve a state of complete global CV risk reduction. [source] Integration of on-the-fly kinetic reduction with multidimensional CFDAICHE JOURNAL, Issue 5 2010Kaiyuan He Abstract A reduction approach for coupling complex kinetics with engine computational fluid dynamics (CFD) code has been developed. An on-the-fly reduction scheme was used to reduce the reaction mechanism dynamically during the reactive flow calculation in order to couple comprehensive chemistry with flow simulations in each computational cell. KIVA-3V code is used as the CFD framework and CHEMKIN is employed to formulate chemistry, hydrodynamics and transport. Mechanism reduction was achieved by applying element flux analysis on-the-fly in the context of the multidimensional CFD calculation. The results show that incorporating the on-the-fly reduction approach in CFD code enables the simulation of ignition and combustion process accurately compared with detailed simulations. Both species and time-dependant information can be provided by the current model with significantly reduced CPU time. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Balancing absolute and relative risk reduction in tobacco control policy: the example of antenatal smoking in Victoria, AustraliaAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2010Nathan Grills Abstract Objective: This descriptive epidemiological analysis aims to explore the benefits, risks and policy balance between a whole-of-population and high-risk reduction approach to reducing antenatal smoking prevalence. Methods: Using Victorian hospital antenatal statistics the rate-ratio for smoking in each hypothesised high prevalence group was calculated and combined with the absolute number of births in each high-risk group. The effect on smoking prevalence of whole-of-population reductions and high-risk group reductions was then modelled. Results: In Victoria, there were higher rates of antenatal smoking among single [RR = 4.67 (3.46,4.42)], teenage women [RR (95%CI) = 3.26 (3.00,3.54)] of indigenous ethnicity [RR = 4.39 (3.94, 4.88)] with low income [RR = 4.67 (4.17,5.22)] and low education attainment [RR = 3.89 (3.47,4.36)] who lived in less accessible areas [RR = 2.14 (1.92,2.39)]. However, as each of these high-risk groups represents a relatively small proportion of mothers, most antenatal smokers are aged 25,34, educated, city-based, non-Indigenous and non-impoverished. Conclusions: The majority of Victorian women who smoke in pregnancy do not belong to traditional high-risk groups. Implications: Absolute reductions in smoking prevalence in high-risk groups can potentially be achieved by whole-of-population prevalence reductions, despite a potential continuance in high relative risk among these groups. Conversely, an exclusive focus on smoking reduction in high-risk groups may fail to reduce the whole-of-population antenatal smoking prevalence. [source] Sparse partial least squares regression for simultaneous dimension reduction and variable selectionJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 1 2010Hyonho Chun Summary., Partial least squares regression has been an alternative to ordinary least squares for handling multicollinearity in several areas of scientific research since the 1960s. It has recently gained much attention in the analysis of high dimensional genomic data. We show that known asymptotic consistency of the partial least squares estimator for a univariate response does not hold with the very large p and small n paradigm. We derive a similar result for a multivariate response regression with partial least squares. We then propose a sparse partial least squares formulation which aims simultaneously to achieve good predictive performance and variable selection by producing sparse linear combinations of the original predictors. We provide an efficient implementation of sparse partial least squares regression and compare it with well-known variable selection and dimension reduction approaches via simulation experiments. We illustrate the practical utility of sparse partial least squares regression in a joint analysis of gene expression and genomewide binding data. [source] Surface-entropy reduction approaches to manipulate crystal forms of ,-ketoacyl acyl carrier protein synthase II from Streptococcus pneumoniaeACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2008Gopalakrishnan Parthasarathy A series of experiments with ,-ketoacyl acyl carrier protein synthase II (FabF) from Streptococcus pneumonia (spFabF) were undertaken to evaluate the capability of surface-entropy reduction (SER) to manipulate protein crystallization. Previous work has shown that this protein crystallizes in two forms. The triclinic form contains four molecules in the asymmetric unit (a.u.) and diffracts to 2.1,Å resolution, while the more desirable primitive orthorhombic form contains one molecule in the a.u. and diffracts to 1.3,Å. The aim was to evaluate the effect of SER mutations that were specifically engineered to avoid perturbing the crystal-packing interfaces employed by the favorable primitive orthorhombic crystal form while potentially disrupting a surface of the protein employed by the less desirable triclinic crystal form. Two mutant proteins were engineered, each of which harbored five SER mutations. Extensive crystallization screening produced crystals of the two mutants, but only under conditions that differed from those used for the native protein. One of the mutant proteins yielded crystals that were of a new form (centered orthorhombic), despite the fact that the interfaces employed by the primitive orthorhombic form of the native protein were specifically unaltered. Structure determination at 1.75,Å resolution reveals that one of the mutations, E383A, appears to play a key role in disfavouring the less desirable triclinic crystal form and in generating a new surface for a packing interaction that stabilizes the new crystal form. [source] | |||||||||||||