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61.
ABSTRACT

Students at community colleges are being placed into developmental writing classes at significantly high rates, as high as 80% at some colleges. Many of these students are students of color, and the need to help them persist and succeed is of increasing importance. The purpose of this study was to investigate the most promising practices by community college developmental writing programs. This article presents a review of more than 245 publications from over 450 authors, synthesized down to 36 validated studies with the goal of informing scholars and practitioners of the current state of the field. Themes emerging from these studies and a conceptual model through which findings can be viewed are presented. The analysis, with a focus on the structural, curricular, andragogical, and relational domains, documents only validated studies about the most promising practices. This article supports, challenges, and recommends how to better serve students in the developmental writing context. This author hopes to change how colleges implement developmental writing practices so that practitioners will be given the best tools to help all students succeed.  相似文献   
62.
First‐generation undergraduate students face challenging cross‐socioeconomic cultural transitions into college life. The authors compared first‐ and non‐first‐generation undergraduate students’ social support, posttraumatic stress, depression symptoms, and life satisfaction. First‐generation participants reported less social support from family and friends, more single‐event traumatic stress, less life satisfaction, and marginally more depression symptomatology than non‐first‐generation participants, but significant generation–gender interactions showed first‐generation women doing worse and first‐generation men doing better than others.  相似文献   
63.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
64.
Integrating knowledge across a firm's value chain (e.g. between R&D, marketing and manufacturing functions), which we denote “Knowledge Integration” (KI), has been consistently found to be a strong predictor of product innovation performance in the management literature. Such cross-functional integration does not occur by chance, but by design, as a result of managerial practices and organizational arrangements. The significant heterogeneity characterizing the diffusion of cross-functional integration across firms is suggestive of the well-known tension between internal and external diffusion of knowledge. In this paper, we argue that the hidden cost of KI is to expose firms to a higher risk of knowledge leakages and provide the first systematic empirical evidence of this apparent tension between internal and external knowledge flows. Based on data from the CMU Survey (one of the rare datasets offering observables on both sides of the tension for a representative set of R&D active firms in the US), we investigate the impact of knowledge spillovers to competitors on internal cross-functional knowledge integration involving the R&D function among manufacturing firms. We find that the intensity of (tacit) R&D knowledge spillovers at the industry-level has a negative and significant impact on the likelihood that firms adopt or achieve KI. Our results therefore suggest that firms may trade their optimal innovative performance against superior appropriability of their rents.  相似文献   
65.
One of the most widely used solutions to fix and preserve organic tissues is formaldehyde, despite reservations regarding its toxicity and the fact that formaldehyde-embalmed bodies lose their original characteristics. Anatomy laboratories have been replacing formaldehyde with solutions that retain the characteristics of fresh tissue. For this purpose, alternative solutions with a very low concentration of formaldehyde or without any formaldehyde have been analyzed. The objective of this study was to compare biometry, coloration, haptic properties, and bacterial load on animal specimens (pig kidneys) embalmed with formaldehyde, and with Chilean Conservative Fixative Solution with and without formaldehyde (formaldehyde chCFS and formaldehyde-free chCFS). Also, the perception of health and biological science students toward specimens treated with different solutions was assessed. The results indicated that there were no significant differences in specimens’ retraction, or bacterial load. Students showed a preference for organs embalmed in formaldehyde chCFS and formaldehyde-free chCFS; indicating that with these treatments they could better visualize structures and that the prosections had greater flexibility and the colors were more similar to those of fresh tissue. Additionally, students recommended the material embalmed in formaldehyde chCFS and formaldehyde-free chCFS for anatomy learning. In contrast, students indicated that formaldehyde-fixation negatively affected their practical experience. In conclusion, embalming with formaldehyde chCFS or formaldehyde-free chCFS provides an advantageous practical experience over the use of formaldehyde and may be an alternative to replace the use of formaldehyde in anatomy laboratories.  相似文献   
66.
ABSTRACT

The recruitment of athletes with limited resources is a global problem in professional sports. In US Major League Baseball, the experience of the Oakland Athletics’ general manager in the last decade turned his “Moneyball” model into a synonym of quantitative analysis in the transfer market of baseball players. His strategy focused on hiring players with outstanding technical skills but relatively low market value. This study adapted this model to the framework of a multiple criteria decision aid (MCDA), by selecting undervalued players who have complementary abilities. The novelty here refers to the joint use of four algorithms explored by the composition of probabilistic preferences (CPP) (i.e., ranking, classification, dynamic evaluation and regularity analysis) and their application to soccer player performance evaluation. The new model analysed the recent transfer of a left-back soccer player to Europe. The results indicated 12 opportunities for better investment, among 32 left and right-back players considered. Two years later, the value of the same player was considerably lower. He played only five matches in the 2018–2019 season, without scoring or providing any assists. On the other hand, the players better classified by the CPP-MB model presented higher performances and market values.  相似文献   
67.
68.
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.  相似文献   
69.
Recent studies indicate that the majority of school psychologists’ time continues to be dedicated to SPED related activities. Despite ongoing calls for school psychologists to expand their roles, why many practitioners do not deliver more comprehensive services is not well understood. This qualitative study investigated facilitators of and barriers to comprehensive and integrated services using the National Association of School Psychologists Model for Comprehensive and Integrated School Psychological Services as the guiding framework. Thirteen full‐time, school‐based practitioners from across the US participated in semi‐structured interviews. Constant‐comparative analysis was used to generate themes. Results indicated that practitioners experienced a number of systemic barriers to (e.g., heavy caseload; inconsistent district policies, priorities, and role definitions; lack of stakeholder involvement) and facilitators of (e.g., resources, graduate training and professional development) comprehensive and integrated service delivery. Participants’ perspectives regarding changes needed to expand their services focused on systemic issues as well. Implications for research and practitioners’ efforts to advocate for systems change are discussed.  相似文献   
70.
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