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41.
ABSTRACT

This article reports on the findings of qualitative, semistructured interviews conducted with 40 older Australian participants and 39 participants in Hong Kong who either did or did not engage in organized learning in the last 6 months. Phenomenology was used to guide the interviews and analysis to explore the experiences and perspectives of these older people. The meaning older people attribute to aging and learning and their possible relationship in their lives in both societies is described and compared.  相似文献   
42.
Cytokines are small proteins secreted by leukocytes in blood in response to infections, thus offering valuable diagnostic information. Given that the same cytokines may be produced by different leukocyte subsets in blood, it is beneficial to connect production of cytokines to specific cell types. In this paper, we describe integration of antibody (Ab) microarrays into a microfluidic device to enable enhanced cytokine detection. The Ab arrays contain spots specific to cell-surface antigens as well as anti-cytokine detection spots. Infusion of blood into a microfluidic device results in the capture of specific leukocytes (CD4 T-cells) and is followed by detection of secreted cytokines on the neighboring Ab spots using sandwich immunoassay. The enhancement of cytokine signal comes from leveraging the concept of reconfigurable microfluidics. A three layer polydimethylsiloxane microfluidic device is fabricated so as to contain six microchambers (1 mm × 1 mm × 30 μm) in the ceiling of the device. Once the T-cell capture is complete, the device is reconfigured by withdrawing liquid from the channel, causing the chambers to collapse onto Ab arrays and enclose cell/anti-cytokine spots within a 30 nl volume. In a set of proof-of-concept experiments, we demonstrate that ∼90% pure CD4 T-cells can be captured inside the device and that signals for three important T-cell secreted cytokines, tissue necrosis factor-alpha, interferon-gamma, and interleukin-2, may be enhanced by 2 to 3 folds through the use of reconfigurable microfluidics.  相似文献   
43.
Community learning centres (CLCs) have been widely established in the Asia-Pacific region as locally managed institutions that offer non-formal educational opportunities and community development activities. Myanmar officially has more than 3,000 centres, which is one of the highest numbers in the region. This article examines the operation of CLCs and their contributions to personal and community development in Padaung, Myanmar. The author’s research is based on six weeks of fieldwork in Myanmar for data collection including semi-structured interviews, focus group discussions and informal conversations. Her findings suggest that CLCs can contribute to the improvement of both individuals’ quality of life and communities’ social capital, which facilitates mutually beneficial collective action. The findings also support the conclusion that CLCs can provide additional educational opportunities beyond the formal system, especially for adults and members of rural communities, e.g. farmers. However, due to constraints in terms of budget, implementing capacity and socio-economic factors, the outreach of CLC activities is still somewhat limited and has yet to reach its full potential.  相似文献   
44.
Impact loading in athletes participating in various sports has been positively associated with increased bone mineral density (BMD), but this has not been investigated in elite Kenyan runners. Body composition and site-specific BMD measures quantified with dual x-ray absorptiometry were measured in 15 elite male Kenyan runners and 23 apparently healthy South African males of different ethnicities. Training load and biomechanical variables associated with impact loading, such as joint stiffness, were determined in the elite Kenyan runners. Greater proximal femur (PF) BMD (g · cm?2) was higher (P = 0.001, ES = 1.24) in the elite Kenyan runners compared with the controls. Six of the 15 (40%) Kenyan runners exhibited lumbar spine (LS) Z-Scores below ?2.0 SD, whereas this was not found in the apparently healthy controls. PFBMD was associated with training load (r = 0.560, P = 0.003) and ankle (r = 0.710, P = 0.004) and knee (r = 0.546, P = 0.043) joint stiffness. Elite Kenyan runners exhibit greater PFBMD than healthy controls, which is associated with higher training load and higher joint stiffness. Our results reaffirm the benefits of impact loading on BMD at a weight-bearing site, while a high prevalence of low LSBMD in the elite Kenyan runners is hypothesised to be the result of a mismatch between energy intake and high training load. Future research investigating energy availability in Kenyan runners and the possible association with musculoskeletal injury should be investigated.  相似文献   
45.
Aim: The aim of this study was to determine the relationships between biomechanical parameters of the gait cycle and race walking economy in world-class Olympic race walkers.

Methods: Twenty-One world-class race walkers possessing the Olympic qualifying standard participated in this study. Participants completed an incremental race walking test starting at 10 km·h?1, where race walking economy (ml·kg?1·km?1) and spatiotemporal gait variables were analysed at different speeds.

Results: 20-km race walking performance was related to race walking economy, being the fastest race walkers those displaying reduced oxygen cost at a given speed (R = 0.760, < 0.001). Longer ground contact times, shorter flight times, longer midstance sub-phase and shorter propulsive sub-phase during stance were related to a better race walking economy (moderate effect, p < 0.05).

Conclusion: According to the results of this study, the fastest race walkers were more economi cal than the lesser performers. Similarly, shorter flight times are associated with a more efficient race walking economy. Coaches and race walkers should avoid modifying their race walking style by increasing flight times, as it may not only impair economy, but also lead to disqualification.  相似文献   
46.
Dalyell T 《New scientist (1971)》1978,77(1096):869-870
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47.
This study examines the perceptions of Chinese students and parents in Hong Kong on homework involvement, assignment type and homework functions. The relationships of homework perceptions to student and parent attributes are also assessed. The sample includes 1393 pairs of students and their parents from 36 primary schools in Hong Kong. Findings of this study show similarities in preference for assignment type across students and parents. Between‐group discrepancies are observed in preference for homework involvement and endorsement of homework functions. Moreover, homework perceptions are found to relate to students’ and parents’ efficacy attributes and involvement behaviour. Findings of this study are discussed in light of the Chinese sociocultural context in Hong Kong. Suggestions are made on the design and use of homework in primary schools by incorporating the views of different stakeholders.  相似文献   
48.
Factors leading to successful professional learning communities (PLCs) have been widely discussed in the West, but little is known about how/whether teachers’ beliefs contribute to PLCs in the Chinese context. This qualitative case study aimed to investigate teachers’ beliefs about teacher learning in PLCs and their influence on collegial learning activities in two departments of a Hong Kong secondary school. Semi-structured interviews and observations were employed to collect data. The findings indicate that teachers in the Chinese Department believed that learning could be achieved in PLCs and their practices of collegial activities were conducive to teacher learning. Conversely, teachers in the English Department did not believe that interacting with colleagues would foster learning and their collegial activities yielded limited accomplishment in teacher growth. It is suggested that teachers’ beliefs play an important role in facilitating or impeding reform initiatives on teacher development. Implications for teacher education and further studies are discussed.  相似文献   
49.
Monocytes represent a class of immune cells that play a key role in the innate and adaptive immune response against infections. One mechanism employed by monocytes for sensing foreign antigens is via toll-like receptors (TLRs)—transmembrane proteins that distinguish classes of foreign pathogens, for example, bacteria (TLR4, 5, and 9) vs. fungi (TLR2) vs. viruses (TLR3, 7, and 8). Binding of antigens activates a signaling cascade through TLR receptors that culminate in secretion of inflammatory cytokines. Detection of these cytokines can provide valuable clinical data for drug developers and disease investigations, but this usually requires a large sample volume and can be technically inefficient with traditional techniques such as flow cytometry, enzyme-linked immunosorbent assay, or luminex. This paper describes an approach whereby antibody arrays for capturing cells and secreted cytokines are encapsulated within a microfluidic device that can be reconfigured to operate in serial or parallel mode. In serial mode, the device represents one long channel that may be perfused with a small volume of minimally processed blood. Once monocytes are captured onto antibody spots imprinted into the floor of the device, the straight channel is reconfigured to form nine individually perfusable chambers. To prove this concept, the microfluidic platform was used to capture monocytes from minimally processed human blood in serial mode and then to stimulate monocytes with different TLR agonists in parallel mode. Three cytokines, tumor necrosis factor-α, interleukin (IL)-6, and IL-10, were detected using anti-cytokine antibody arrays integrated into each of the six chambers. We foresee further use of this device in applications such as pediatric immunology or drug/vaccine testing where it is important to balance small sample volume with the need for high information content.  相似文献   
50.
ABSTRACT

This study aimed to describe stationary overhead throwing biomechanics in South African cricketers, considering playing level, and relative to baseball. Kinematics and ground reaction forces were collected during throwing trials. Inverse dynamics was used to calculate joint kinetics. Inter-subject variability was calculated using the coefficient of variance. A one-dimensional statistical parametric mapping ANOVA was conducted to assess differences between the kinematic waveforms in elite and amateur cricketers (p < 0.05). Fifteen cricketers (elite = 8; amateur = 7) participated in this study. The basic parameters of a cricketer’s throwing action are described. Substantial inter-subject variability was noted for all variables, except lumbopelvic movement. Cricketers presented with 74.9 ± 27.3° glenohumeral external rotation and 94.8 ± 23.7° elbow flexion, at maximum external rotation (MER). Amateur cricketers displayed decreased elbow flexion range of motion between 2-14% of the throwing cycle (F = 9.365;p = 0.01); greater shoulder (121.0vs85.9 N; F = 0.36,p = 0.021) and elbow compression (105.6vs72.8 N;F = 0.007,p = 0.043), and superior shoulder force (203.1vs115.5 N;F = 2.43,p = 0.022) at MER, when compared with elite cricketers. Cricketers display similarities to baseball pitchers when throwing overhead from a stationary position. The “preparatory arc” utilised is different to the wind-up noted for baseball. The forces exerted on the shoulder and elbow, in amateur cricketers specifically, are substantially greater at MER and may indicate the potential risk for injury.  相似文献   
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