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101.
David B. Resnik Elizabeth Wager Grace E. Kissling 《Journal of the Medical Library Association》2015,103(3):136-139
Objective
This study gathered information about the retraction policies of the top 200 scientific journals, ranked by impact factor.Methods
Editors of the top 200 science journals for the year 2012 were contacted by email.Results
One hundred forty-seven journals (74%) responded to a request for information. Of these, 95 (65%) had a retraction policy. Of journals with a retraction policy, 94% had a policy that allows the editors to retract articles without authors’ consent.Conclusions
The majority of journals in this sample had a retraction policy, and almost all of them would retract an article without the authors’ permission. 相似文献102.
Jared Keengwe Grace Onchwari Joachim Agamba 《Education and Information Technologies》2014,19(4):887-898
Although rapid advances in technology has allowed for the growth of collaborative e-learning experiences unconstrained by time and space, technology has not been heavily infused in the activities of teaching and learning. This article examines the theory of constructivism as well as the design of e-learning activities using constructivist principles. The manner in which constructivist theory supports e-Learning is explored, and extrapolating from this pedagogical theory, some implications are provided to model effective practices of the characteristics and capacities of this powerful learning environment. 相似文献
103.
Giraud G Pethig R Schulze H Henihan G Terry JG Menachery A Ciani I Corrigan D Campbell CJ Mount AR Ghazal P Walton AJ Crain J Bachmann TT 《Biomicrofluidics》2011,5(2):24116
The manipulation of ribosomal RNA (rRNA) extracted from E. coli cells by dielectrophoresis (DEP) has been demonstrated over the range of 3 kHz-50 MHz using interdigitated microelectrodes. Quantitative measurement using total internal reflection fluorescence microscopy of the time dependent collection indicated a positive DEP response characterized by a plateau between 3 kHz and 1 MHz followed by a decrease in response at higher frequencies. Negative DEP was observed above 9 MHz. The positive DEP response below 1 MHz is described by the Clausius-Mossotti model and corresponds to an induced dipole moment of 3300 D with a polarizability of 7.8×10(-32) F m(2). The negative DEP response above 9 MHz indicates that the rRNA molecules exhibit a net moment of -250 D, to give an effective permittivity value of 78.5 ε(0), close to that of the aqueous suspending medium, and a relatively small surface conductance value of ~0.1 nS. This suggests that our rRNA samples have a fairly open structure accessible to the surrounding water molecules, with counterions strongly bound to the charged phosphate groups in the rRNA backbone. These results are the first demonstration of DEP for fast capture and release of rRNA units, opening new opportunities for rRNA-based biosensing devices. 相似文献
104.
Individuals experiencing a highly caring, task-involving, and low ego-involving exercise climate have reported greater ownership in exercise class and empowerment to exercise in general. Purpose: This study examined the relationship between ownership and empowerment in exercise, with 2 context-specific outcomes, satisfaction with physical education (PE) and physical activity, respectively. Given the mission of PE to foster individuals’ lifelong physical activity habit, the perceptions of high school students were collected for this study. Ownership in exercise was hypothesized to be significantly, positively correlated with students reporting satisfaction in PE more than their satisfaction in physical activity, whereas empowerment in exercise was hypothesized to be more strongly, positively correlated with students’ physical activity satisfaction. A second purpose of this study was to test the measurement quality of the updated Empowerment in Exercise Scale (EES; now 13 items). Method: High school students (N = 502, 43% female) in a Midwestern U.S. school district completed a survey. Results: Confirmatory factor analysis supported the internal measurement structure of the EES (λ = .62–.91; McDonald’s omega = .89) across student gender (strong invariance). Additionally, the structural equation modeling analysis revealed only 1 parameter moderated by the students’ gender (latent mean of ownership). The hypotheses were supported, such that ownership in exercise was more strongly correlated with PE satisfaction (r = .87) and empowerment in exercise had a stronger correlation with physical activity satisfaction (r = .92). Conclusion: These results support the beneficial effect a satisfying experience in PE can have on students’ satisfaction with physical activity outside of school. 相似文献
105.
Willis R. Whitney 《Journal of The Franklin Institute》1944,237(4):265-270
106.
ABSTRACTScholars writing on agency argue that normally, individuals who experience social structures as comfortable will tend to want to reproduce them while those who experience these structures as oppressive will want to change them. This is a bleak outlook because it suggests that those in positions of power and influence are less likely to seek to overhaul the very system of rewards and punishments that benefits them. However, there are exceptions to this pattern: instances where those who experience the structures as comfortable, nevertheless, work at transforming them. This article introduces an alternative perspective to current transformation discourses by seeking to understand why such exceptions exist. It argues that critical engagement is an important dimension of such transformation, and examines how it interacts with reflexivity to shape individual choices and reformulate interest. Drawing on a hermeneutic phenomenological analysis of in-depth interviews with 10 academics who have been identified as agents of change at one university in South Africa, we reveal how individuals are able to shift their understanding of what is or is not in their interest in a context where raced, gendered and classed interests are deeply embedded in the fabric of the society. In such contexts, reflexivity and critical personal engagement with one’s context can lead to a shift in interest and then consciousness as the individual comes to see and experience things from a different vantage point, opening up the possibility for a changed relationship with the social structure and its constraints and determining influence. 相似文献
107.
Michael Windle Carol Miller-Tutzauer Grace M. Barnes John Welte 《Child development》1991,62(1):179-189
Adolescent perceptions of help-seeking social resources (e.g., parents, friends, school counselor, clergyman) they would utilize if they were having substance abuse difficulties were investigated for samples of early and middle adolescents. 8 different perceived help-seeking categories were identified, and intergroup comparisons were made with regard to gender and ethnic/racial group and with regard to alcohol consumption, substance-related problems, and school misconduct. 2 perceived help-seeking categories had the highest levels of problem behaviors. The first category consisted of adolescents who identified friends as the only social resource they would utilize if they were having substance abuse problems. The second category, referred to as social isolates, indicated that they would not utilize any social resource if they were having substance abuse problems. There were approximately twice as many male social isolates as female social isolates, and blacks and Hispanics were highly overrepresented in the social isolate category. 相似文献
108.
OBJECTIVE: It has often been hypothesized that because of a lack of early satisfactory attachments, sex offenders grow up unable to form relationships with adults, which makes them susceptible to pursue intimacy in maladaptive ways. This research aims to empirically examine the parental bonding patterns for a group of sex offenders, comparing child molesters and rapists. METHOD: Seventy-six men convicted of a sexual offense (57 child molesters and 19 rapists) completed the parental bonding instrument (PBI), and were assessed by means of a semi-structured clinical interview. RESULTS: Affectionless control style of parental bonding was highly prevalent amongst the sex offenders. There was some suggestion that low parental care was associated with childhood abuse and disturbances, particularly for child molesters. High overprotection in mothers was linked with parental separation and sex play with male peers in childhood. CONCLUSIONS: There is a need to replicate the study with non-sexual offenders as a comparison group, and to establish whether the PBI provides a useful adjunct to studies of adult romantic attachment in sex offenders. 相似文献
109.
The construction of a building may change the microclimate in the vicinity, and planning indicators in a master plan may directly affect the outdoor physical environmental quality in residential areas. An inappropriate plan for a site may accelerate wind and intensify vortexes over places on the pedestrian levels, which leads to an adverse outdoor environment. Therefore, the design of a cluster of buildings should not focus only on the buildings but also provide a good outdoor environment around the buildings. To tackle the problem of inadequate wind environment, the relationship between the building’s floor area ratio and height was identified in this study as the main planning indicator to be examined on its effects on the outdoor wind environment. A computational fluid dynamics (CFD) model was hence developed to simulate the wind conditions generated by some typical site layouts with different values for planning indicators under relevant weather conditions, which were typical of those in Hangzhou, China. The simulated wind conditions are assessed using the wind speed ratio over the whole area of the building cluster at the pedestrian level. The effects on the local wind condition due to the varying of the planning indicators are discussed whilst considering the potential construction costs. The indicators resulting in better external conditions are highlighted in the conclusion as the recommendation which could be used as a rule of thumb by architects and planners at the master planning stage. The study disproves the common belief in the practice that a lower floor area ratio means fewer buildings and therefore greater external comfort. In fact, the higher the building, the greater the outdoor comfort wind zone for pedestrians. However, the increment in comfort area is limited to buildings extending from 25 to 30 levels. 相似文献
110.
Justine E. Hoch Ori Ossmy Whitney G. Cole Shohan Hasan Karen E. Adolph 《Child development》2021,92(4):1337-1353
Pre-mobile infants and caregivers spontaneously engage in a sequence of contingent facial expressions and vocalizations that researchers have referred to as a social “dance.” Does this dance continue when both partners are free to move across the floor? Locomotor synchrony was assessed in 13- to 19-month-old infant–mother dyads (N = 30) by tracking each partner’s step-to-step location during free play. Although infants moved more than mothers, dyads spontaneously synchronized their locomotor activity. For 27 dyads, the spatiotemporal path of one partner uniquely identified the path of the other. Clustering analyses revealed two patterns of synchrony (mother-follow and yo-yo), and infants were more likely than mothers to lead the dance. Like face-to-face synchrony, locomotor synchrony scaffolds infants’ interactions with the outside world. 相似文献