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91.
Paul Evan Peters 《Publishing Research Quarterly》1988,4(3):20-24
Paul Evan Peters begins his discussion of library standards with a convincing argument that the acceptance by librarians of
the need for order and standards is not a character flaw. Rather, in promoting the use of standards, librarians are efficiently
forwarding their missions to build and organize collections and to make them accessible to their clients. Pointing out the
economic realities of contemporary libraries, Peters further argues that standards are appealing because they help librarians
to control costs.
Paul Evan Peters, systems coordinator for the New York Public Library, is vice chairperson of the National Information Standards
Organization and principal representative of the American Library Association to Accredited Standards Committee X3 (Information
Processing Systems). Address for correspondence. 相似文献
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96.
Carl M. Tausig 《Educational theory》1969,19(3):223-235
97.
Matthew J. Kennedy Harold D. Ladouceur Tiffany Moeller Dickson Kirui Carl A. Batt 《Biomicrofluidics》2012,6(4)
The present work describes the operation and simulation of a microfluidic laminar-flow mixer. Diffusive mixing takes place between a core solution containing lipids in ethanol and a sheath solution containing aqueous buffer, leading to self assembly of liposomes. Present device architecture hydrodynamically focuses the lipid solution into a cylindrical core positioned at the center of a microfluidic channel of 125 × 125-μm2 cross-section. Use of the device produces liposomes in the size range of 100–300 nm, with larger liposomes forming at greater ionic strength in the sheath solution and at lower lipid concentration in the core solution. Finite element simulations compute the concentration distributions of solutes at axial distances of greater than 100 channel widths. These simulations reduce computation time and enable computation at long axial distances by utilizing long hexahedral elements in the axial flow region and fine tetrahedral elements in the hydrodynamic focusing region. Present meshing technique is generally useful for simulation of long microfluidic channels and is fully implementable using comsol Multiphysics. Confocal microscopy provides experimental validation of the simulations using fluorescent solutions containing fluorescein or enhanced green fluorescent protein. 相似文献
98.
Abstract This study examined dissonance in physical activity (PA) between two youth-specific hip-derived intensity cut-points for the Actiwatch (AW), and compared PA between hip and wrist placements using site-specific cut-points. Twenty-four children aged 11.2?±?0.5 years wore the AW on the right hip and non-dominant wrist during a typical school day. Minutes of sedentary behaviour and vigorous activity were greater using Puyau et al. (2002) cut-points, but light, moderate, and moderate-to-vigorous (MVPA) were greater when derived using Puyau et al. (2004) cut-points (P?0.01). Total hip activity counts were lower than wrist. Sedentary minutes were greater at the hip, but minutes of light, vigorous and MVPA were lower (P?0.01). Moderate minutes were greater at the hip, but differed only when applying the Puyau et al. (2004) cut-points (P?0.01). In conclusion, data comparisons between two hip derived AW cut-points and between hip and wrist data are inappropriate. Future researchers using the AW at the hip should present data reduced using both published cut-points. As hip and wrist data differ, the wrist placement is preferable as it will likely increase children's compliance to monitoring protocols due to reduced obtrusiveness compared to the hip. 相似文献
99.
Johnson RJ Ross MW Taylor WC Williams ML Carvajal RI Peters RJ 《Child abuse & neglect》2006,30(1):75-86
OBJECTIVE: The current study examined the prevalence and characteristics of childhood sexual abuse in a jailed-based population. METHODOLOGY: A retrospective, self-reported survey was administered over an 8-week period to a random sample of 100 men who were incarcerated in a county jail in Southeastern Texas. The survey included questions about childhood sexual experiences before and after puberty, drug history and use, and sexual risk-taking behaviors. RESULTS: Of the 100 male inmates who participated in this study, 59% reported experiencing some form of sexual abuse before puberty, and all such instances occurred before or at the age of 13 years. The first episode of childhood sexual abuse began at an average age of 9.6 years (SD = 2.4), and ended at an average age of 13.0 years (SD = 2.3). Kissing and touching without intercourse (64%) was the common pattern of sexual abuse experience reported. The total number of perpetrators was 165, with 10% male and 90% female. Friends (n = 72) and family (n = 56) were the most frequent perpetrators. CONCLUSION: Childhood sexual abuse may be more prevalent among inmates than among males in the general population. These results show a high percentage of inmates who report a history of childhood sexual abuse; this rate is higher than those reported by other studies for incarcerated males. The findings support the belief held by professionals in the criminal justice field that a significant number of incarcerated males may have been victims of sexual abuse. 相似文献
100.
Thai Thi Minh Carl Erik Schou Larsen Andreas Neef 《The Journal of Agricultural Education and Extension》2013,19(2):179-194
Abstract Purpose: The objective of this article is to analyze the introduction of participatory extension approaches (PEA) in the predominantly supply-driven, hierarchical Vietnamese extension system. Drawing on the case of the so-called Farmer Livestock School (FLS) concept, the authors investigate the potential and challenges of scaling up and out the FLS/PEA principles of participatory training methods, encompassing intensive and interactive training sessions, group-based sharing of experience, practical learning, and learning-by-doing processes. Design/Methodology/Approach: The article is based on data collected and synthesized from 36 pilot communes from 2000 to 2007 and draws on the extensive insider experience of two of its authors during their work for a DANIDA-funded livestock project. Findings: At the micro-scale and with external support, FLS has been a successful experiment of using participatory extension approaches in farmer training and extension in the livestock sector. Yet, possibilities of scaling up and institutionalizing FLS remain a challenge given the capacity and resource limitations and the resistance at various levels within the Vietnamese extension system. Practical Implications: The starting point for successfully institutionalizing participatory extension approaches should be to assess the existing system's root problems and capacities and then gradually and systematically introduce institutional innovations rather than aiming at a complete overhaul of a system that may result in the creation of a parallel universe. Originality/Value: The FLS project provided a unique opportunity to study the enabling and constraining factors of institutionalizing participatory extension approaches in a traditionally top-down oriented extension system beyond the immediate duration of an externally orchestrated project. 相似文献