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Usually, the purpose of the response surface optimization is to be able to locate the optimum operating levels of the regressors. In quantitative structure-activity relationship (QSAR) studies, the predicting variable reflects any biological property, and the regressors are structural and physico-chemical terms. By contrast to the Box-Wilson approach, the regressors are continously distributed. The working technique is demonstrated on an example adapted from organophosphorus pesticide research. It was found that the maximum neurotoxicity depends on lipophilic and steric substituent properties.  相似文献   
463.
The Archaeology of Food Preference   总被引:1,自引:0,他引:1  
Food preference is a socially constructed concept in which both consumers and producers define what is "good to eat." Staple crops and daily meals are an important component of these definitions, as the regular use of particular foods reinforces norms of identity. Food preferences also affect agricultural systems because choices among cultivars are based on social needs in addition to economic variables such as yield and caloric value. Through textual and archaeological evidence, the trajectory of rice production is examined for Sri Lanka, the Brahmaputra Valley, the Tamil region, and Vijayanagara. In these regions and elsewhere in South Asia, shared ideologies of food preference resulted in a consensus mode of agricultural production: Irrigation works increased the tax base for political leaders and the donation base for temple economies, but they also benefited local inhabitants who would have been able to partake of a preferred food on a more regular basis.  相似文献   
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In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.  相似文献   
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Interposition agents are a well-known device for attaching legacy applications to distributed systems. However, agents are difficult to build and are often large, monolithic pieces of software which are suited only to limited applications or systems. We solve this problem with Bypass, a language and a tool for quickly building multiple small agents that can be combined together to create powerful yet manageable software.  相似文献   
468.
The potential effectiveness of statistical haplotype inference makes it an area of active exploration over the last decade. There are several complications of statistical inference, including: the same algorithm can produce different solutions for the same data set, which reflects the internal algorithm variability; different algorithms can give different solutions for the same data set, reflecting the discordance among algorithms; and the algorithms per se are unable to evaluate the reliability of the solutions even if they are unique, this being a general limitation of all inference methods. With the aim of increasing the confidence of statistical inference results, consensus strategy appears to be an effective means to deal with these problems. Several authors have explored this with different emphases. Here we discuss two recent studies examining the internal algorithm variability and among-algorithm discordance, respectively, and evaluate the different outcomes of these analyses, in light of Orzack (2009) comment. Until other, better methods are developed, a combination of these two approaches should provide a practical way to increase the confidence of statistical haplotyping results.  相似文献   
469.
The interneuronal network that produces local bending in the leech is distributed, in the sense that most of the interneurons involved are activated in all forms of local bending, even those in which their outputs would produce inappropriate movements. Such networks have been found to control a number of different behaviors in a variety of animals. This article reviews three issues: the physiological and modeling observations that led to the conclusion that local bending in leeches is controlled by a distributed system; what distributed processing means for this and other behaviors; and why the leech interneuronal network may have evolved to be distributed in the first place. © 1995 John Wiley & Sons, Inc.  相似文献   
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