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Hua-jie Zhu - One of the best experts on this subject based on the ideXlab platform.
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progression of absolute Configuration determination in natural product chemistry using optical rotation dispersion matrix determinant and electronic circular dichroism methods
Current Organic Chemistry, 2011Co-Authors: Shengding Zhao, Lan Shen, Duqiang Luo, Hua-jie ZhuAbstract:With the development of separation materials, more and more complex natural products with poly-stereogenic centers are obtained. However, due to small quantity of the isolated compounds, or no crystal formed, or complex 2D NMR correlation signals, absolute Configuration Identification for these compounds becomes difficult. Now, computational methods provide researchers many benefits in structural determinations for chiral natural products. Computational methods include (1) optical rotation (OR) and its dispersion (ORD) computations; (2) electronic circular dichroism (ECD or CD) calculations; (3) computations of determinant of matrix for stereogenic centers. In methods (1) to (2), the mostly used quantum theory contained density functional theory (DFT) with different basis sets, e.g. B3LYP/aug-cc-pVDZ//B3LYP/6-31G(d). Effects from solvents on OR value can be investigated using different corresponding software. In the cases, optimizations performed in the corresponding solution are helpful to obtain the correct predictions although it is not usual at present time. Matrix model as one of the mathematic methods is different from quantum methods, which is of easily being understood and effective in absolute Configuration assignment for acyclic chiral compounds. In this review, necessary theory basis for the three methods are simply introduced for modern readers, the focus of which is the application of these methods in natural product chemistry by various examples reported in different journals from 1998 to the end of April of 2010 except for matrix method to the May of 2010 based on an experimental chemist's viewpoints.
Huang Xingyuan - One of the best experts on this subject based on the ideXlab platform.
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application and research of product data management pdm system on Configuration management
Aeronautical Computing Technique, 2007Co-Authors: Huang XingyuanAbstract:Based on the 4 fundamental contents of the Configuration Management,which are the Configuration Identification(CI),the Configuration Control,the Configuration Status Accounting and the Configuration Audit,incorporating the actual flow of OA system,this paper introduces the Configuration Management and its applications on product R D processes,through the employment of the typical application software,Product Data Management System.Also,the problems emerging in the process of the application and its solutions are discussed in this paper.
Shengding Zhao - One of the best experts on this subject based on the ideXlab platform.
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progression of absolute Configuration determination in natural product chemistry using optical rotation dispersion matrix determinant and electronic circular dichroism methods
Current Organic Chemistry, 2011Co-Authors: Shengding Zhao, Lan Shen, Duqiang Luo, Hua-jie ZhuAbstract:With the development of separation materials, more and more complex natural products with poly-stereogenic centers are obtained. However, due to small quantity of the isolated compounds, or no crystal formed, or complex 2D NMR correlation signals, absolute Configuration Identification for these compounds becomes difficult. Now, computational methods provide researchers many benefits in structural determinations for chiral natural products. Computational methods include (1) optical rotation (OR) and its dispersion (ORD) computations; (2) electronic circular dichroism (ECD or CD) calculations; (3) computations of determinant of matrix for stereogenic centers. In methods (1) to (2), the mostly used quantum theory contained density functional theory (DFT) with different basis sets, e.g. B3LYP/aug-cc-pVDZ//B3LYP/6-31G(d). Effects from solvents on OR value can be investigated using different corresponding software. In the cases, optimizations performed in the corresponding solution are helpful to obtain the correct predictions although it is not usual at present time. Matrix model as one of the mathematic methods is different from quantum methods, which is of easily being understood and effective in absolute Configuration assignment for acyclic chiral compounds. In this review, necessary theory basis for the three methods are simply introduced for modern readers, the focus of which is the application of these methods in natural product chemistry by various examples reported in different journals from 1998 to the end of April of 2010 except for matrix method to the May of 2010 based on an experimental chemist's viewpoints.
Jessica Keyes - One of the best experts on this subject based on the ideXlab platform.
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software Configuration management
2004Co-Authors: Jessica KeyesAbstract:INTRODUCTION TO SOFTWARE Configuration MANAGEMENT SCM and Process Improvement Measurements and Metrics Benefits of SCM SCM Components Configuration Identification Configuration Change Control Configuration Status Accounting Configuration Auditing Implementing SCM in the Organization Manage the Risks of SCM Summary PROJECT MANAGEMENT IN A CM ENVIRONMENT Who Writes the Project Plan What Goes Into the Project Plan CM-based Project Plan Components Configuration Status Accounting Summary THE DOD CM PROCESS MODEL CM Benefits, Risks, and Cost Impact CM Life-Cycle Management and Planning Relation to Systems Engineering Process Implementing the CM Process Measuring and Evaluating the CM Process CM Benefits and Risks by Program Life-Cycle Activity Effect Process Improvement and Document Lessons Learned Summary Configuration Identification How Configuration Identification Works Configuration Identification General Activity Guides Product Structure Configuration Items Configuration Item Selection Criteria General Guidance Additional Factors Configuration Documentation Configuration Baselines Document and Item Identification Engineering Release Interface Management Summary Configuration CONTROL The Process of Configuration Control Engineering Change Proposal Summary Configuration STATUS ACCOUNTING Typical CSA Information over the Acquisition Program Life Cycle Configuration Status Accounting Process Evaluation Checklist Summary A PRACTICAL APPROACH TO DOCUMENTATION AND Configuration STATUS ACCOUNTING Configuration Identification Configuration Status Accounting The Effective Documentation of Systems Methods and Standards Maintaining Documentation Summary Configuration VERIFICATION AND AUDIT Configuration Verification and Audit Concepts and Principles Summary A PRACTICAL APPROACH TO Configuration VERIFICATION AND AUDIT Components of a Design and Document Verification Methodology Components of a Configuration Audit Methodology Components of a Testing Methodology The QA Process The Test Plan Test Automation Summary Configuration MANAGEMENT AND DATA MANAGEMENT CM-Related Data Management Concepts and Principles Summary Configuration CHANGE MANAGEMENT What Is Configuration Change Management? The Maintenance Process The Product Baseline Types of Maintenance Corrective Maintenance Maintenance Costs A Model for Maintenance Configuration Management Steps Managing Maintenance Personnel Measuring Effectiveness Summary Configuration MANAGEMENT AND SOFTWARE ENGINEERING STANDARDS REFERENCE The Standards Bodies A Summary of the EIA Standard (EIA-649) ANSI IEEE ISO Summary METRICS AND Configuration MANAGEMENT REFERENCE What Metrics Are and Why They Are Important Traditional CM Metrics IEEE Process for Measurement Metrics as a Component of the Process Maturity Framework Steps to Take in Using Metrics IEEE Defined Metrics IT Developer's List of Metrics Summary CM AUTOMATION Automating CM A Selection of CM Tool Summary Appendices Appendix A Project Plan Appendix B DoD Engineering Change Proposal Appendix C Sample Data Dictionary Appendix D Problem Change Report Appendix E Test Plan Appendix F Program Code Inspection Form Appendix G Sample Inspection Plan Appendix H QA Handover Document Appendix I System Service Request Appendix J Document Change Request (DCR) Appendix K Problem/Change Report Appendix L Software Requirements Changes Appendix M Problem Report (PR) Appendix N Corrective Action Processing (CAP) Appendix O Specification Change Notice Appendix P Project Statement of Work Appendix Q Problem Trouble Report (PTR) Appendix R Library/Baseline Change Form Appendix S Sample Maintenance Plan Appendix T Software Configuration Management Plan (SCMP) Appendix U Acronyms and Glossary Appendix V Functional Configuration Audit (FCA) Checklist Appendix W Physical Configuration Audit (PCA) Checklist Appendix X SCM Guidance for Achieving the "Repeatable" Level on the Software Appendix Y Supplier CM Market Analysis Questionnaire
Marc Laruelle - One of the best experts on this subject based on the ideXlab platform.
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models and methods for derivation of in vivo neuroreceptor parameters with pet and spect reversible radiotracers
Nuclear Medicine and Biology, 2001Co-Authors: Mark Slifstein, Marc LaruelleAbstract:Abstract The science of quantitative analysis of PET and SPECT neuroreceptor imaging studies has grown considerably over the past decade. A number of methods have been proposed in which receptor parameter estimation results from fitting data to a model of the underlying kinetics of ligand uptake in the brain. These approaches have come to be collectively known as model-based methods and several have received widespread use. Here, we briefly review the most frequently used methods and examine their strengths and weaknesses. Kinetic modeling is the most direct implementation of the compartment models, but with some tracers accurate input function measurement and good compartment Configuration Identification can be difficult to obtain. Other methods were designed to overcome some particular vulnerability to error of classical kinetic modeling, but introduced new vulnerabilities in the process. Reference region methods obviate the need for arterial plasma measurement, but are not as robust to violations of the underlying modeling assumptions as methods using the arterial input function. Graphical methods give estimates of V T without the requirement of compartment model specification, but provide a biased estimator in the presence of statistical noise. True equilibrium methods are quite robust, but their use is limited to experiments with tracers that are suitable for constant infusion. In conclusion, there is no universally "best" method that is applicable to all neuroreceptor imaging studies, and carefully evaluation of model-based methods is required for each radiotracer.