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Primary Emphasis (primary + emphasis)

Distribution by Scientific Domains

Medical Sciences	42%
Business, Economics, Finance and Accounting	28%

Selected Abstracts

Nonlinear multiple regression methods: a survey and extensions

INTELLIGENT SYSTEMS IN ACCOUNTING, FINANCE & MANAGEMENT, Issue 1 2010
Kenneth O. Cogger
Abstract This paper reviews some nonlinear statistical procedures useful in function approximation, classification, regression and time-series analysis. Primary emphasis is on piecewise linear models such as multivariate adaptive regression splines, adaptive logic networks, hinging hyperplanes and their conceptual differences. Potential and actual applications of these methods are cited. Software for implementation is discussed, and practical suggestions are given for improvement. Examples show the relative capabilities of the various methods, including their ability for universal approximation. Copyright © 2010 John Wiley & Sons, Ltd. [source]

A prevalence survey for zoonotic enteric bacteria in a research monkey colony with specific emphasis on the occurrence of enteric Yersinia

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2001
Stephen J. Vore
Transmissible pathogenic and opportunistic zoonotic enteric bacteria comprise a recognized occupational health threat to exposed humans from non-human primates (NHPs). In an effort to evaluate the occurrence of selected enteric organisms with zoonotic and biohazard potential in a research colony setting, we performed a prevalence study examining 61 juvenile and young adult rhesus macaques participating in a transplant immunology project. Primary emphasis was directed specifically to detection of pathogenic enteric Yersinia, less well-documented and reported NHP pathogens possessing recognized significant human disease potential. NHPs were surveyed by rectal culture during routine health monitoring on three separate occasions, and samples incubated using appropriate media and specific selective culture methods. Enteric organisms potentially transmissible to humans were subcultured and identified to genus and species. Significant human pathogens of the Salmonella/Shigella, Campylobacter, and enteric Yersinia groups were not isolated throughout the survey, suggesting prevalence of these organisms may generally be quite low. [source]

Preventing growth in amphetamine use: long-term effects of the Midwestern Prevention Project (MPP) from early adolescence to early adulthood

ADDICTION, Issue 10 2009
Nathaniel R. Riggs
ABSTRACT Aim The aim of the current study was to examine the long-term effect of an early adolescent substance abuse prevention program on trajectories and initiation of amphetamine use into early adulthood. Design Eight middle schools were assigned randomly to a program or control condition. The randomized controlled trial followed participants through 15 waves of data, from ages 11,28 years. This longitudinal study design includes four separate periods of development from early adolescence to early adulthood. Setting The intervention took place in middle schools. Participants A total of 1002 adolescents from one large mid-western US city were the participants in the study. Intervention The intervention was a multi-component community-based program delivered in early adolescence with a primary emphasis on tobacco, alcohol and marijuana use. Measures At each wave of data collection participants completed a self-report survey that included questions about life-time amphetamine use. Findings Compared to a control group, participants in the Midwestern Prevention Project (MPP) intervention condition had reduced growth (slope) in amphetamine use in emerging adulthood, a lower amphetamine use intercept at the commencement of the early adulthood and delayed amphetamine use initiation. Conclusions The pattern of results suggests that the program worked first to prevent amphetamine use, and then to maintain the preventive effect into adulthood. Study findings suggest that early adolescent substance use prevention programs that focus initially on the ,gateway' drugs have utility for long-term prevention of amphetamine use. [source]

Connecting Atmosphere and Wetland: Trace Gas Exchange

GEOGRAPHY COMPASS (ELECTRONIC), Issue 2 2009
Peter M. Lafleur
This article reviews the exchange of carbon dioxide (CO2) and methane (CH4) gases between wetland and atmosphere, with a primary emphasis on ecosystem-scale fluxes and their environmental controls. It is intended to complement a previous review of wetland energy and water exchanges (Lafleur 2008). It is shown that wetland exchanges of these gases are greatly variable in space and time, especially CH4. Most wetlands appear to be sinks for atmospheric CO2, while almost all are emitters of CH4. The strongest environmental control on the CO2 flux is drought, which often determines whether a wetland will be a net sink or source for atmospheric CO2. Due to complex biochemistry and transport mechanisms, methane efflux from wetlands often ranges over several orders of magnitude within a single wetland and among wetlands, making it difficult to quantify the environmental controls on this flux. The magnitude of gas fluxes is not strongly related to wetland type, which implies that modelling of these fluxes should consider wetlands a continuum and attempt to address processes as they vary along this continuum instead of as discrete entities. Although more research is required into the magnitude, variation and controls on trace gas fluxes in all wetland types, some wetlands (tropical and temperate marshes) are particularly understudied. [source]

Experimental techniques in high-vacuum anionic polymerization

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 24 2005
David Uhrig
Abstract Experimental methods used in high-vacuum anionic polymerization are described in detail, with extensive illustrations to demonstrate proper procedures and techniques. These descriptions include construction and operation of the vacuum line, handling purification chemicals, ampulization techniques, short-path distillations, initiator synthesis, polymerization procedures, and linking reactions using chlorosilanes. A primary emphasis is placed on safety. We believe that this review of these methods will be useful to scientists working in the field of anionic polymerization and may also benefit other researchers in performing tasks requiring ultra-high-purity reaction conditions. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6179,6222, 2005 [source]

An introduction to coil array design for parallel MRI

NMR IN BIOMEDICINE, Issue 3 2006
Michael A. Ohliger
Abstract The basic principles of radiofrequency coil array design for parallel MRI are described from both theoretical and practical perspectives. Because parallel MRI techniques rely on coil array sensitivities to provide spatial information about the sample, a careful choice of array design is essential. The concepts of coil array spatial encoding are first discussed from four qualitative perspectives. These qualitative descriptions include using coil arrays to emulate spatial harmonics, choosing coils with selective sensitivities to aliased pixels, using coil sensitivities with broad k -space reception profiles, and relying on detector coils to provide a set of generalized projections of the sample. This qualitative discussion is followed by a quantitative analysis of coil arrays, which is discussed in terms of the baseline SNR of the received images as well as the noise amplifications (g -factor) in the reconstructed data. The complications encountered during the experimental evaluation of coil array SNR are discussed, and solutions are proposed. A series of specific array designs are reviewed, with an emphasis on the general design considerations that motivate each approach. Finally, a set of special topics is discussed, which reflect issues that have become important, especially as arrays are being designed for more high-performance applications of parallel MRI. These topics include concerns about the depth penetration of arrays composed of small elements, the use of adaptive arrays for systems with limited receiver channels, the management of inductive coupling between array elements, and special considerations required at high field strengths. The fundamental limits of spatial encoding using coil arrays are discussed, with a primary emphasis on how the determination of these limits impacts the design of optimized arrays. This review is intended to provide insight into how arrays are currently used for parallel MRI and to place into context the new innovations that are to come. Copyright © 2006 John Wiley & Sons, Ltd. [source]

State and Local Governance Fifteen Years Later: Enduring and New Challenges

PUBLIC ADMINISTRATION REVIEW, Issue 2008
Frank J. Thompson
This article draws on the contributions to this issue and related evidence to assay the extent to which the states and larger local governments have moved in directions endorsed by the Winter Commission in 1993. The commission's recommendations targeted (1) the political context of state and local governance, with a particular focus on executive leadership, campaign finance reform, and citizen engagement; (2) the specifics of public administration, with primary emphasis on empowering managers through internal deregulation and bolstering human resource capacity; and (3) the nature of the relationship between the national government and the states in a key policy arena. Significant changes in the fabric of state and local governance have occurred in each of these three areas over the last 15 years. Many of these modifications are consonant with the thrust of the Winter Commission report, but the evidence also points to the limits of state and local reform. Further reform initiatives should be built on systematic efforts to advance knowledge concerning the origins, nature, and outcomes of the array of institutions and processes present at the state and local levels. [source]