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711.
This paper argues that contemporary understandings of cosmopolitan literature are significantly limited by their dependence on sympathetic attachments as constitutive of cosmopolitan practice. I trace a genealogy of the connection between sympathy, cosmopolitanism, and the novel that extends from Adam Smith and Immanuel Kant to Martha Nussbaum and Kwame Anthony Appiah, in order to contend that contemporary models of cosmopolitan reading rely on problematically normative definitions of the ‘human’. J.M. Coetzee's Boyhood, I propose, suggests an alternative model of cosmopolitan reading that neither equates sympathy with humanity, nor precludes those who ‘feel apart’ from participation in cosmopolitan community.  相似文献   
712.
Circulating tumor cells (CTCs) are prognostic markers for the recurrence of cancer and may carry molecular information relevant to cancer diagnosis. Dielectrophoresis (DEP) has been proposed as a molecular marker-independent approach for isolating CTCs from blood and has been shown to be broadly applicable to different types of cancers. However, existing batch-mode microfluidic DEP methods have been unable to process 10 ml clinical blood specimens rapidly enough. To achieve the required processing rates of 106 nucleated cells/min, we describe a continuous flow microfluidic processing chamber into which the peripheral blood mononuclear cell fraction of a clinical specimen is slowly injected, deionized by diffusion, and then subjected to a balance of DEP, sedimentation and hydrodynamic lift forces. These forces cause tumor cells to be transported close to the floor of the chamber, while blood cells are carried about three cell diameters above them. The tumor cells are isolated by skimming them from the bottom of the chamber while the blood cells flow to waste. The principles, design, and modeling of the continuous-flow system are presented. To illustrate operation of the technology, we demonstrate the isolation of circulating colon tumor cells from clinical specimens and verify the tumor origin of these cells by molecular analysis.  相似文献   
713.
Abstract

Ingesting carbohydrate plus protein following prolonged exercise may restore exercise capacity more effectively than ingestion of carbohydrate alone. The objective of the present study was to determine whether this potential benefit is a consequence of the protein fraction per se or simply due to the additional energy it provides. Six active males participated in three trials, each involving a 90-min treadmill run at 70% maximal oxygen uptake (run 1) followed by a 4-h recovery. At 30-min intervals during recovery, participants ingested solutions containing: (1) 0.8 g carbohydrate · kg body mass (BM)?1 · h?1 plus 0.3 g · kg?1 · h?1 of whey protein isolate (CHO-PRO); (2) 0.8 g carbohydrate · kg BM?1 · h?1 (CHO); or (3) 1.1 g carbohydrate · kg BM?1 · h?1 (CHO-CHO). The latter two solutions matched the CHO-PRO solution for carbohydrate and for energy, respectively. Following recovery, participants ran to exhaustion at 70% maximal oxygen uptake (run 2). Exercise capacity during run 2 was greater following ingestion of CHO-PRO and CHO-CHO than following ingestion of CHO (P ≤ 0.05) with no significant difference between the CHO-PRO and CHO-CHO treatments. In conclusion, increasing the energy content of these recovery solutions extended run time to exhaustion, irrespective of whether the additional energy originated from sucrose or whey protein isolate.  相似文献   
714.

Reduced feedback during practice has been shown to be detrimental to movement accuracy in children but not in young adults. We hypothesized that the reduced accuracy is attributable to reduced movement parameter learning, but not pattern learning, in children. A rapid arm movement task that required the acquisition of a motor pattern scaled to specific spatial and temporal parameters was used to investigate the effects of feedback (FB) frequency (100% vs. 62% faded) on motor learning differences between 19 school-age children and 19 young adults. Adults and children practiced the task for 200 trials under the 100% or faded FB condition on Day 1 and returned on Day 2 for a no-FB retention test. On the retention test, children who practiced with reduced feedback performed with greater temporal parameter errors, but not pattern error, than children who received frequent feedback. Motor skill learning in children is influenced by feedback frequency during practice that affects parameter learning but not pattern learning.  相似文献   
715.
716.
Regression mixture models are a new approach for finding differential effects which have only recently begun to be used in applied research. This approach comes at the cost of the assumption that error terms are normally distributed within classes. The current study uses Monte Carlo simulations to explore the effects of relatively minor violations of this assumption, the use of an ordered polytomous outcome is then examined as an alternative which makes somewhat weaker assumptions, and finally both approaches are demonstrated with an applied example looking at differences in the effects of family management on the highly skewed outcome of drug use. Results show that violating the assumption of normal errors results in systematic bias in both latent class enumeration and parameter estimates. Additional classes which reflect violations of distributional assumptions are found. Under some conditions it is possible to come to conclusions that are consistent with the effects in the population, but when errors are skewed in both classes the results typically no longer reflect even the pattern of effects in the population. The polytomous regression model performs better under all scenarios examined and comes to reasonable results with the highly skewed outcome in the applied example. We recommend that careful evaluation of model sensitivity to distributional assumptions be the norm when conducting regression mixture models.  相似文献   
717.
The purpose of this study was to explore patronage and usage of the children’s section of a public library. Patrons of the children’s section of a public library in a small Northern Arizona city were observed for a total of 24 h over 12 sessions. Analytic induction was used to formulate categories based on field notes made during these observations. An observation of a story time session was also conducted. Data from an interview with a librarian was triangulated with observational data. In terms of patronage, the clear majority of parents/adult caregivers accompanying a child or children to the children’s section were observed to be female and speaking English. In terms of usage, the following three categories of early learning were identified from the data: early literacy learning; learning how to use a library; and other developmentally appropriate learning. Study results offer insight into both the role of females in the intergenerational transmission of literacy and the rich learning young children experience at the library. At a time of library cutbacks and closures across the United States, this study speaks to the continued relevance of the children’s section of the public library in providing free early learning experiences during the pivotal birth to five age range.  相似文献   
718.
We report an in-depth study of the long-term reproducibility and reliability of droplet dispensing in digital microfluidic devices (DMF). This involved dispensing droplets from a reservoir, measuring the volume of both the droplet and the reservoir droplet and then returning the daughter droplet to the original reservoir. The repetition of this process over the course of several hundred iterations offers, for the first time, a long-term view of droplet dispensing in DMF devices. Results indicate that the ratio between the spacer thickness and the electrode size influences the reliability of droplet dispensing. In addition, when the separation between the plates is large, the volume of the reservoir greatly affects the reproducibility in the volume of the dispensed droplets, creating "reliability regimes." We conclude that droplet dispensing exhibits superior reliability as inter-plate device spacing is decreased, and the daughter droplet volume is most consistent when the reservoir volume matches that of the reservoir electrode.  相似文献   
719.
720.
Because the vice presidency of the United States was for so many years considered a “nonjob,” it is hardly surprising that preserving its records has been a nonissue for most of the nation's history. However, the vice presidency in recent years has emerged as an executive rather than a decorative role, and vice presidential papers have been included both in legislation to promote access to historical documents, and presidential orders delaying that access, such as Executive Order 13,233. The end result is that researchers arguably have less access to vice presidential records than before the groundbreaking Presidential Records Act of 1978, which should have opened doors to this increasingly rich source of government information.  相似文献   
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