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1.
In the aftermath of the 2016 election of President Trump, a veritable cottage industry of opinion pieces, blogs, and articles emerged overnight, most of which seemed to agree that only the post-truth could explain how a racist, misogynistic, neo-nationalist member of the economic elite could win a presidential election. This article, in contrast, is inspired by Barbara Christian’s injunction that we question why a given statement, concept, or theory is now acceptable when before it was not. Operating in this spirit, we critique post-truth critics for neglecting the material tradition of ideological criticism in favor of epistemological explanations for understanding post-truth literature; we then offer two case studies—American drug policy and housing policy—to illustrate the racial amnesia required for claiming that only now do we live in a post-truth era.  相似文献   
2.
Recent research into composing processes has focused on instructional intervention strategies that promote effective composition practices within computerized writing environments. The field of computers and composition has benefitted both from advances in computing tools and developments in learning theory. The innovative computer tool discussed in this paper uses the macro-command language of a full-featured word processor to enact strategic support designed to help writers with their written work. From a theoretical standpoint, this tool created a writing environment based on Vygotskian theory of mediated learning and was grounded in an instructional strategy known as “procedural facilitation.” To evaluate the effectiveness of this computerprompting tool, a second macro application was used to log student keystrokes, thereby tracking student writing development, revisionary practices, and keystroke reactions to the prompting partner. Students using the prompting tool enacted divergent and convergent thinking assistance that appeared at the bottom of their computer screens while the system saved a process record of their keystrokes. Procedures for creating macro-driven prompting programs and keystroke-logging devices are discussed. Additionally, a catalog of prompts and summary of keystroke-mapping benefits are provided. Finally, our research using the macro-driven prompting partner and keystroke-register tool is detailed.  相似文献   
3.
Amplification of multiple unique genetic targets using the polymerase chain reaction (PCR) is commonly required in molecular biology laboratories. Such reactions are typically performed either serially or by multiplex PCR. Serial reactions are time consuming, and multiplex PCR, while powerful and widely used, can be prone to amplification bias, PCR drift, and primer-primer interactions. We present a new thermocycling method, termed thermal multiplexing, in which a single heat source is uniformly distributed and selectively modulated for independent temperature control of an array of PCR reactions. Thermal multiplexing allows amplification of multiple targets simultaneously—each reaction segregated and performed at optimal conditions. We demonstrate the method using a microfluidic system consisting of an infrared laser thermocycler, a polymer microchip featuring 1 μl, oil-encapsulated reactions, and closed-loop pulse-width modulation control. Heat transfer modeling is used to characterize thermal performance limitations of the system. We validate the model and perform two reactions simultaneously with widely varying annealing temperatures (48 °C and 68 °C), demonstrating excellent amplification. In addition, to demonstrate microfluidic infrared PCR using clinical specimens, we successfully amplified and detected both influenza A and B from human nasopharyngeal swabs. Thermal multiplexing is scalable and applicable to challenges such as pathogen detection where patients presenting non-specific symptoms need to be efficiently screened across a viral or bacterial panel.  相似文献   
4.
5.
Some have argued for a common language in the field of instructional design in an effort to reduce misunderstandings and simplify a multitude of synonymous terms and concepts. Others feel that this goal is undesirable in that it precludes development and flexibility. In this article we propose an ontology-building process as a way for readers to compare and analyze terms and concepts across theories. This process entails the development of categories that emerge from the literature, and the comparison of theories across categories. Such a process can reveal broader concepts that exist beyond specific theoretical terminology, differences in meanings behind common terms used by theorists, a greater understanding of the theorists’ intent, and discontinuities and gaps within the theoretical literature.  相似文献   
6.
Publishing companies have embraced strategic, business, and market planning, but may not fully grasp its potential. This article describes their applications in a publishing environment, focusing on fundamental information required if the process is to have a beneficial outcome, as well as risks for the organization if planning is poorly conceived. This article is adapted from a presentation at a marketing and fulfillment seminar sponsored by the Society for Scholarly Publishing, April 21, 1988.  相似文献   
7.
Health professionals are collecting and charting data about the family history of their patients in order to determine if a predisposition to heart, stroke, cancer and other debilitating conditions can be detected or alleviated through patient education and preventive medicine. Family history-taking for the purposes of preventive medicine is introduced, along with a brief history of the field. The pedigree chart and the genogram are described and their use by health personnel is discussed. A brief search strategy on MEDLINE and a selected bibliography are presented to aid the health sciences librarian to find information on the family history, genograms or pedigree charts.  相似文献   
8.
AIM: In 2002, a discussion in the United Kingdom (UK) between South-west Information for Clinical Effectiveness (SWICE) librarians and a member of the South Australian Department of Human Services Libraries' Consortium (SAHSLC) raised the possibility of developing an after-hours virtual reference service between the two consortium groups. The aim of the service is to put medical practitioners in contact with a librarian when urgent help is required in finding clinical medical information after hours. METHODS: A trial project has begun and has been given the name 'Chasing the Sun'. The service will make use of time-zone differences between the UK and Australia, so that librarians at work in another country will be able to answer urgent patient-related queries that cannot wait until normal office hours. RESULTS: This paper looks at the development of 'Chasing the Sun' from initial concept, funding proposal and trial project stage to implementation. It includes details of the groundwork, software evaluation, trials, outcomes, cost and benefits, future directions and potential problems yet to be experienced or overcome. CONCLUSION: This service is the first of its kind between health libraries in the world and offers potential for future worldwide expansion.  相似文献   
9.
Jena RK  Yue CY 《Biomicrofluidics》2012,6(1):12822-1282212
This report studies the surface modification of cyclic olefin copolymer (COC) by 2-methacryloyloxyethyl phosphorylcholine (MPC) monomer using photografting technique for the purpose of biointerface applications, which demonstrate resistance to both protein adsorption and cell adhesion in COC-based microfluidic devices. This is essential because the hydrophobic nature of COC can lead to adsorption of specific compounds from biological fluids in the microchannel, which can affect the results during fluidic analysis and cause clogging inside the microchannel. A correlation was found between the irradiation time and hydrophobicity of the modified substrate. Static water contact angle results show that the hydrophilicity property of the MPC-grafted substrate improves with increasing irradiation time. The contact angle of the modified surface decreased to 20 ± 5° from 88 ± 3° for the untreated substrate. The surface characterization of the modified surface was evaluated using x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR spectroscopy). Attenuated total reflection-FTIR and XPS results show the presence of the phosphate group (P-O) on modified COC substrates, indicating that the hydrophilic MPC monomer has successfully grafted on COC. Finally, it was demonstrated that cell adhesion and protein adsorption on the MPC modified COC specimen has reduced significantly.  相似文献   
10.

Purpose

The purpose of the present review was to use existing, published data to provide an estimate of the amount of change in six-minute walk test distance (Δ6MWT) that represents a clinically meaningful change in individuals with chronic heart failure (CHF).

Methods

The present review included two separate literature searches of the CINAHL and Medline databases for articles that: (1) reported the intraclass correlation coefficient (ICC) of the 6MWT in individuals with CHF, and (2) used the 6MWT along with either aerobic capacity or health-related quality of life (HRQL) as study endpoints in randomized controlled trials (RCTs) of exercise-based intervention for individuals with CHF. The ICCs were used to calculate the minimum detectable difference (MDD) at the 95% confidence interval for each included study. The Δ6MWT associated with aerobic capacity and HRQL within-group effect sizes for the intervention and control groups in each included RCT was analyzed using receiver operating characteristic (ROC) curves.

Results

Thirteen articles reported the ICC for the 6MWT. The mean (standard deviation) MDD calculated based on these data was 43.1(16.8) m. Eighteen RCTs measured the 6MWT and either aerobic capacity and/or HRQL. A Δ6MWT of 40–45 m was associated with at least moderate aerobic capacity and HRQL effect sizes in the intervention groups. The Δ6MWT thresholds that discriminated between intervention and control groups using ROC curves revealed the following sensitivity/specificity for the respective thresholds: 19 m, 94.4/83.3%, 32 m, 83.3/94.4%, and 48 m 44.4/100% (AUC = .935, p = .009, CI95% .855, 1.015).

Conclusions

A Δ6MWT of approximately 45 m appears to exceed measurement error and be associated with significant changes in either aerobic capacity and/or HRQL.Key Words: heart failure, six-minute walk test, clinically meaningful change, minimum detectable difference  相似文献   
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