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191.
Thomas S. Dee 《Economics of Education Review》2011,30(5):924-937
Wisconsin's influential Learnfare initiative is a conditional cash penalty program that sanctions a family's welfare grant when covered teens fail to meet school attendance targets. In the presence of reference-dependent preferences, Learnfare provides uniquely powerful financial incentives for student performance. However, a 10-county random-assignment evaluation suggested that Learnfare had no sustained effects on school enrollment and attendance. This study evaluates the data from this randomized field experiment. In Milwaukee County, the Learnfare procedures were poorly implemented and the random-assignment process failed to produce balanced baseline traits. However, in the nine remaining counties, Learnfare increased school enrollment by 3.5 percent (effect size = 0.08) and attendance by 4.5 percent (effect size = 0.10). These results suggest that well-designed financial incentives may be an effective mechanism for improving the school persistence of at-risk students at scale. 相似文献
192.
The present study explores Greek parents’ views on parental educational involvement and its impact on adolescent scholastic and social development. Specifically, aspects of parental involvement such as the achieved objectives of current parent–school communication, the psychological climate dominating teacher–parent interactions and parents’ suggestions for improvement of current policies and practices are examined. Four hundred and seventy‐five parents participated in the study. Findings showed that family–school communication is believed to be insufficient in Greece, despite the fact that parents tend to: (1) regard their cooperation with teachers as determinative of adolescent academic and psychosocial development; (2) consider teachers to be friendly and caring; and (3) believe that secondary school provides some opportunities for constructive parental involvement. These paradoxes are discussed and explained as a result of radical changes in current social and educational values, principles and objectives. 相似文献
193.
Thomas F. Nelson Laird 《Research in higher education》2011,52(6):572-588
Most studies of curricular diversity have focused on the effects of participation in diversity courses on student outcomes.
Though the results have been positive, these studies have used limited measures of curricular diversity and there is a great
need for a complimentary body of research demonstrating what faculty and what types of courses are more likely to include
diversity. This study relies on 12 diversity inclusivity items derived from a comprehensive model of how diversity is included
into a course to investigate how much diversity is being included in collegiate courses and what predicts diversity inclusivity,
as measured by two scales: diverse grounding and inclusive learning. The results, based on 7,101 responses from faculty participating
in the 2007 Faculty Survey of Student Engagement, suggest that most faculty are including diversity in their courses in some
way, but that women and faculty of color tend to include diversity to a greater extent than their colleagues. Also, courses
taught in the soft fields are more likely to be inclusive of diversity. 相似文献
194.
Thomas F. Nelson Laird Amy K. Garver Amanda Suniti Niskodé-Dossett 《Research in higher education》2011,52(3):261-277
Using data from over 9,000 faculty members that participated in the Faculty Survey of Student Engagement (FSSE), this study
examined the moderating role a range of course characteristics played on the effects of gender on the percentage of class
time spent on various activities, a measure of teaching style. Results revealed gender differences, but that the gaps between
men and women in lecturing and active classroom practices varied by disciplinary area, course level, and the number of times
a course had been taught by the same instructor. The results confirm that gender effects depend on context, which implies
that efforts to improve teaching and learning must also adapt to the instructional context. 相似文献
195.
In 2004, the University of Michigan Medical School reduced its gross anatomy curriculum. To determine the effect of this reduction on resident perceptions of their clinical preparedness, we surveyed alumni that included residents from the original and new shortened curricula. A Likert-scale survey was sent to four classes of alumni. Respondents were compared in old curriculum (OC) and new curriculum (NC) groups, surgical specialty (SS) and nonsurgical specialty (NS) groups, and subgroups of SS and NS were compared for differences between OC and NC. Mean response scores were compared using independent samples T-tests. As a single population (n = 110), respondents felt their anatomy education prepared them well for residency, that a more robust anatomy curriculum would be helpful, that dissection was important to their residency preparation, and that a 4th year anatomy elective was effective in expanding their anatomy education and preparing them for residency. No significant difference existed between OC and NC groups, neither as a whole nor as SS and NS subgroups. The SS group felt dissection was more important to their residency preparation than the NS group (P = 0.001) and that a more robust anatomy curriculum would have better prepared them for residency (P = 0.001). Thirty percent of SS respondents who did not take a 4th year elective commented that they wish they had. Fourth year anatomy electives were highly valued by residents, and respondents felt that they should be offered to students as a way of revisiting anatomy following the 1st year of clinical training. 相似文献
196.
Thomas K. Gaisser 《Journal of The Franklin Institute》2011,348(3):453-458
This award recognizes two specific discoveries that constitute the experimental discovery of neutrino oscillations. In 1998 the Super-Kamiokande group under the leadership of Yoji Totsuka published their paper, “Evidence for Oscillation of Atmospheric Neutrinos” in Physical Review Letters [1]. The paper describes a deficit of muon-type neutrinos from below the detector relative to those from above. It explains this “atmospheric neutrino anomaly” as a result of transformation of some of the muon neutrinos into another type of neutrino. Four years later, the group led by Arthur McDonald described “Direct Evidence for Neutrino Flavor Transformation from Neutral-Current Interactions in the Sudbury Neutrino Observatory” [2] in the same journal. This experiment detected lower energy neutrinos from deep inside the Sun. By measuring all flavors of neutrinos with large rates, the SNO collaboration showed definitively that the long-standing “solar neutrino puzzle” was another manifestation of neutrino oscillations. As a result of these two experiments, we now understand that neutrinos can change identities during propagation and that both the solar and atmospheric neutrino “problems” result from the same underlying phenomenon of oscillations. A consequence of neutrino oscillations is that neutrinos, previously thought to be massless, must have a non-zero rest mass. 相似文献
197.
Thomas Gould 《Publishing Research Quarterly》2011,27(1):36-53
Perhaps nothing strikes more fear into the hearts of all tenure-track professors than the process itself. Are four papers in this journal good enough? Are eight papers in another okay? What if someone doesn’t like me or my area of research? These issues have plagued academia since the first essay was penned by the first researcher hundreds of years ago. While personal bias and journal preference continue to infect honest tenure reviews, solutions exist. This does not mean we have a magic bullet to solve issues of bullying or elitism. However, if we are honest in our desire to improve the Academy, we should avail ourselves of every possible tool for improvement. This essay is based on a survey sent to 2,500 mass communication educators. Of the almost 500 respondents, roughly 10% took the time to express emotions that ranged from fear and confusion to outright rage and anger, all because what ought to be clear is not. The author offers 10 ideas of how academia can improve its evaluation of new faculty, as well as a few suggestions regarding the unnecessary inclusion of personal issues in a process that ought to be about creating better researchers and teachers. 相似文献
198.
Thomas W. Simpson 《Ethics and Information Technology》2011,13(1):29-38
Trust online can be a hazardous affair; many are trustworthy, but some people use the anonymity of the web to behave very badly indeed. So how can we improve the quality of evidence for trustworthiness provided online? I focus on one of the devices we use to secure others’ trustworthiness: tracking past conduct through online reputation systems. Yet existing reputation systems face problems. I analyse these, and in the light of this develop some principles for system design, towards overcoming these challenges. In providing better evidence for trustworthiness online, so we can also encourage people actually to be trustworthy more often, which is an ethically welcome outcome. 相似文献
199.
Found in all eukaryotic cells, linker histones H1 are known to bind to and rearrange nucleosomal linker DNA. In vitro, the fundamental nature of H1∕DNA interactions has attracted wide interest among research communities-from biologists to physicists. Hence, H1∕DNA binding processes and structural and dynamical information about these self-assemblies are of broad importance. Targeting a quantitative understanding of H1 induced DNA compaction mechanisms, our strategy is based on using small-angle x-ray microdiffraction in combination with microfluidics. The usage of microfluidic hydrodynamic focusing devices facilitates a microscale control of these self-assembly processes, which cannot be achieved using conventional bulk setups. In addition, the method enables time-resolved access to structure formation in situ, in particular, to transient intermediate states. The observed time dependent structure evolution shows that the H1∕DNA interaction can be described as a two-step process: an initial unspecific binding of H1 to DNA is followed by a rearrangement of molecules within the formed assemblies. The second step is most likely induced by interactions between the DNA and the H1's charged side chains. This leads to an increase in lattice spacing within the DNA∕protein assembly and induces a decrease in the correlation length of the mesophases, probably due to a local bending of the DNA. 相似文献
200.
We examined differences in anthropometry and training between 64 Triple Iron ultra-triathletes competing over 11.4 km swimming, 540 km cycling, and 126.6 km running, and 71 Ironman triathletes competing over 3.8 km swimming, 180 km cycling, and 42.2 km running. The association of anthropometry and training with race time was investigated using multiple linear regression analysis. The Triple Iron ultra-triathletes were smaller (P < 0.05), had shorter limbs (P < 0.05), a higher body mass index (P < 0.05), and larger limb circumferences (P < 0.01) than the Ironman triathletes. The Triple Iron ultra-triathletes trained for more hours (P < 0.01) and covered more kilometres (P < 0.01), but speed in running during training was slower compared with the Ironman triathletes (P < 0.01). For Triple Iron ultra-triathletes, percent body fat (P = 0.022), training volume per week (P < 0.0001), and weekly kilometres in both cycling (P < 0.0001) and running (P < 0.0001) were related to race time. For Ironman triathletes, percent body fat (P < 0.0001), circumference of upper arm (P = 0.006), and speed in cycling training (P = 0.012) were associated with total race time. We conclude that both Triple Iron ultra-triathletes and Ironman triathletes appeared to profit from low body fat. Triple Iron ultra-triathletes relied more on training volume in cycling and running, whereas speed in cycling training was related to race time in Ironman triathletes. 相似文献