Web 2.0 technologies such as Facebook, a popular social networking site, provide educators with new possibilities for reaching
their students. As these technologies are new, there is not a total understanding of how these technologies could best be
used in education. This study helps to develop this understanding by investigating how appropriate students find student-teacher
interactions on Facebook. The results indicate that students find passive behaviors more appropriate than active behaviors
with no difference depending on whether students or teachers perform the behaviors. Additionally, men find student-teacher
interactions on Facebook more appropriate than women while no difference exists between undergraduate and graduate students,
and age was not related to finding the interactions more or less appropriate. 相似文献
BACKGROUND: There is a diagnostic dilemma when a child presents with rib fractures after cardiopulmonary resuscitation (CPR) where child abuse is suspected as the cause of collapse. We have performed a systematic review to establish the evidence base for the following questions: (i) Does cardiopulmonary resuscitation cause rib fractures in children? (ii) If so, what are the frequency and characteristics of these fractures that may help to distinguish them from rib fractures caused by physical abuse? METHODS: We performed a literature search of original articles, references, textbooks, and conference abstracts, published in any language from 1950 to 1 October 2005. Articles were identified from ASSIA, Caredata, Medline, Ovid Medline in Process, ChildData, CINAHL, Embase, ISI Proceedings, SIGLE, Science Citation Index, Social Science Citation Index, and TRIP databases. We included all studies that addressed rib fractures and CPR in children less than 18 years, and excluded review articles, expert opinion, consensus guidelines, and studies that were significantly methodologically flawed on critical appraisal. Each study underwent two independent reviews (with a third review if there was disagreement). Each reviewer used standardized criteria for study definition, data extraction, and critical appraisal, to determine the quality of the study and to establish if it met the inclusion criteria of this systematic review. FINDINGS: Of the 427 studies reviewed, 6 were included: 1 case control, 4 cross-sectional, and 1 case series. These represent data on 923 children who underwent CPR. Three children sustained rib fractures as a result of resuscitation; all three of these had fractures that were anterior (two mid-clavicular and one costo-chondral). We did not find any child in the literature who had a posterior rib fracture due to CPR. Resuscitation was performed variably by both medical and non-medical personnel. CONCLUSION: Rib fractures after cardiopulmonary resuscitation are rare. When they do occur, they are anterior and may be multiple. As the studies performed to date did not use the most sensitive techniques for detecting rib fractures, further prospective studies of children would be valuable to provide additional clarification on this question. 相似文献
Purpose:The study aimed to describe youth time-use compositions,focusing on time spent in shorter and longer bouts of sedentary behavior and physical activity(PA),and to examine associations of these time-use compositions with cardiometabolic biomarkers.Methods:Accelerometer and cardiometabolic biomarker data from 2 Australian studies involving youths 7-13 years old were pooled(complete cases with accelerometry and adiposity marker data,n=782).A 9-component time-use composition was formed using compositional data analysis:time in shorter and longer bouts of sedentary behavior;time in shorter and longer bouts of light-,moderate-,or vigorous-intensity PA;and"other time"(i.e.,non-wear/sleep).Shorter and longer bouts of sedentary time were defined as<5 min and>5 min,respectively.Shorter bouts of light-,moderate-,and vigorous-intensity PA were defined as<1 min;longer bouts were defined as≥1 min.Regression models examined associations between overall time-use composition and cardiometabolic biomarkers.Then,associations were derived between ratios of longer activity patterns relative to shorter activity patterns,and of each intensity level relative to the other intensity levels and"other time",and cardiometabolic biomarkers.Results:Confounder-adjusted models showed that the overall time-use composition was associated with adiposity,blood pressure,lipids,and the summary score.Specifically,more time in longer bouts of light-intensity PA relative to shorter bouts of light-intensity PA was significantly associated with greater body mass index z-score(zBMI)(β=1.79;SE=0.68)and waist circumference(β=18.35,SE=4.78).When each activity intensity was considered relative to all higher intensities and"other time",more time in light-and vigorous-intensity PA,and less time in sedentary behavior and moderate-intensity PA,were associated with lower waist circumference.Conclusion:Accumulating PA,particularly light-intensity PA,in frequent short bursts may be more beneficial for limiting adiposity compared to accumulating the same amount of PA at these intensities in longer bouts. 相似文献
Microfluidics is an emerging technology which allows the miniaturization, integration, and automation of fluid handling processes. Microfluidic systems offer low sample consumption, significantly reduced processing time, and the prospect of massive parallelization. A microfluidic platform was developed for the control of the soluble cellular microenvironment of Saccharomyces cerevisiae cells, which enabled high-throughput monitoring of the controlled expression of alpha-synuclein (aSyn), a protein involved in Parkinson's disease. Y-shaped structures were fabricated using particle desorption mass spectrometry-based soft-lithography techniques to generate biomolecular gradients along a microchannel. Cell traps integrated along the microchannel allowed the positioning and monitoring of cells in precise locations, where different, well-controlled chemical environments were established. S. cerevisiae cells genetically engineered to encode the fusion protein aSyn-GFP (green fluorescent protein) under the control of GAL1, a galactose inducible promoter, were loaded in the microfluidic structure. A galactose concentration gradient was established in the channel and a time-dependent aSyn-GFP expression was obtained as a function of the positioning of cells along the galactose gradient. Our results demonstrate the applicability of this microfluidic platform to the spatiotemporal control of cellular microenvironment and open a range of possibilities for the study of cellular processes based on single-cell analysis. 相似文献
Since the late 1970s, European funding of the arts has been a feature of the mixed‐funding regime and support of a range of community arts, training, heritage and regeneration programmes in Member States. In the late 1980s, following widened membership and more direct policy engagement by the European Commission, regional development began to support increasing levels of investment in culture, notably heritage, cultural tourism and city regeneration through arts venues. Meanwhile the Commission's own culture programmes have focused on Cities of Culture, language and heritage projects.
However, the funding of culture through the various Structural Funds (although not categorised as such at either European, national and regional levels) has dwarfed that of the Culture Unit. No cultural policy or plan for this significant amount of investment in cultural facilities has been evident, and such programmes have largely bypassed national arts policy, being directed through regional and local authority economic development, tourism and regeneration departments.
Promotion of European ‘Common Culture’ was expounded in the Maastricht Treaty and, it is argued, these objectives have driven increased city‐regional autonomy. Notwithstanding difficulties in categorising grant data in cultural terms, this chapter measures the impact and distribution of such regional funding across beneficiary countries and within the eligible regions. A UK survey provides a regional breakdown of projects receiving support in the 1990s and European funding used as part of partnership funding (lottery, regeneration programmes). The chapter concludes that, while the funding of these cultural projects has been under‐estimated and ‘hidden’, its concentration in city arts and heritage venues raises questions for both European and national cultural policy: whether cultural investment has been of the right type, in the right place; or whether European common culture aspirations have ignored local and more culturally diverse opportunities. In short, whether form has followed funding. 相似文献
Synchronised swimming involves a variety of sculling movements essential for body support and propulsion but its study is scarce. We aimed to biomechanically compare standard and contra-standard sculling techniques, and to observe the relationship between measures. Six synchronised swimmers performed two, 30 s maximal intensity, fully tethered standard and contra-standard sculling motions. Kinetic and kinematic data were obtained using a load-cell and underwater cameras, respectively. Force decreased along both techniques’ bouts, but no differences in-between techniques were noted for any kinetic variables. Standard sculling presented a higher cycle rate and a lower elbow mean angle than the contra-standard sculling (2.4 ± 0.3 vs. 2.0 ± 0.2 cycles/s and 134.1 ± 5.8 and 141.5 ± 4.7°, p < 0.05). In the standard sculling, by removing and maintaining the variation between participants (rw and r, respectively), the absolute mean force was directly related with cycle rate (rw = 0.60) and wrist angular velocity during flexion (r = 0.82), while in the contra-standard condition the force was inversely associated with wrist mean angle (r = ?0.95) and directly with hand speed (rw = 0.76), and elbow angular velocity (rw ≈ 0.60). Therefore, technique learning and training require different attention by coaches and swimmers. 相似文献
Hand paddles and parachutes have been used in order to overload swimmers, and consequently increase the propulsive force generation in swimming. However, their use may affect not only kinematical parameters (average speed, stroke length and stroke rate), but also time gaps between propulsive phases, assessed through the index of coordination (IdC). The objective of this study was to assess the effects of hand paddles and parachute use, isolated or combined, on kinematical parameters and coordination. Eleven swimmers (backstroke 50-m time: 29.16 ± 1.43 s) performed four 15-m trials in a randomised order at maximal intensity: (1) without implements (FREE), (2) with hand paddles (HPD), (3) with parachute (PCH) and (4) with hand paddles plus parachute (HPD+PCH). All trials were video-recorded (60 Hz) in order to assess average speed, stroke rate, stroke length, five stroke phases and index of coordination. When average swimming speed was compared to FREE, it was lower in PCH and HPD+PCH, and higher in HPD. Stroke rate decreased in all overloaded trials compared to FREE. The use of hand paddles and parachute increased and decreased stroke length, respectively. In addition, propulsive phase duration was increased when hand paddles were used, and time gaps shifted towards zero (no time gap), especially when hand paddles were combined with parachute. It is conceivable that the combined use of hand paddles and parachute, once allowing overloading both propulsive and resistive forces, provides a specific stimulus to improve muscle strength and propulsive continuity. 相似文献