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71.
Jenna Sessions Kelsey Bourbeau Mattina Rosinski Taylor Szczygiel Rachael Nelson Naveen Sharma 《European Journal of Sport Science》2016,16(8):1064-1072
The purpose of this study is to measure the effects of carbohydrate ingestion during exercise in the heat by measuring markers of gastrointestinal damage and inflammation. Methods: Active subjects (n?=?7) completed two 60-min running trials in a heated environment (70% VO2max, 30°C). At minute 20 of exercise, subjects consumed a carbohydrate gel (Cho) (27?g), or a non-carbohydrate placebo (nCho). Plasma endotoxin, I-FABP, TNF-α, IL-6, IL-1β, IL-10, and MCP-1 were measured pre-exercise, 20-min post-exercise, and again 2-h, and 4-h post-exercise. Results: Endotoxin increased 20-min post-exercise compared to pre in the Cho trial only (p?=?.03). I-FABP levels increased 20-min post-exercise in the Cho trial only compared to pre-exercise (p?=?.003). I-FABP levels were also increased in Cho trial 20-min post-exercise when compared to same time point in the nCho trial (p?=?.032). TNF-α increased 20-min post-exercise in the Cho trial only compared to pre (p?=?.03). Plasma IL-6 concentration increased 20-min post-exercise when compared to pre in both the Cho (p?=?.002) and nCho (p?=?.009), but remained elevated at the 2-h time point in the nCho trial (p?=?.03). I-FABP and several plasma cytokines (TNF-α, MCP-1, Il-6) returned to baseline sooner in the Cho trial. Conclusions: Ingestion of carbohydrate gel during exercise in the heat enhances markers of gastrointestinal wall damage. 相似文献
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73.
Sujeet Kumar Sharma Mohamed Sarrab Hafedh Al-Shihi 《Interactive Learning Environments》2017,25(7):847-858
The growth of Smartphone usage, increased acceptance of electronic learning (E-learning), the availability of high reliability mobile networks and need for flexibility in learning have resulted in the growth of mobile learning (M-learning). This has led to a tremendous interest in the acceptance behaviors related to M-learning users among the information systems researchers. Despite a large amount of significant research in the field of M-learning, the measurement of user acceptance of M-learning has not received attention. This research study intends to develop and validate a survey that measures users’ acceptance of M-learning. A total sample of 806 university and higher college students from different institutes in Oman participated in this study. This research study was conducted in two stages. The first stage using a sample size of 388 students initiated a generic questionnaire, and examined factorial validity and reliability. The second stage that was conducted using different sample of 418 students employed confirmatory factor analysis to establish factorial validity and measurement invariance. A correlated six-factor model (Flexibility, Suitability, Enjoyment, Efficiency, Economic and Social) was fit using maximum likelihood estimation. The internal consistency and item reliability of Mobile Learning Acceptance Measure was found to be at acceptable level for both samples. 相似文献
74.
Reflective learning can assist a learner’s purposeful and conscious manipulation of ideas toward meaningful learning and knowledge
integration. Blogs have been used to support reflection, but Blogs usually do not provide overt mechanisms for students to
make connections between different parts of an experience, which is integral to reflective activity. A blogging-mapping tool
was designed to support the reflective learning process. The tool allowed students to write blog posts, attach up to five
keywords to each post, and link the keywords on a concept map. This study aimed to seek patterns of participants’ use of the
tool, including evidence of reflective learning, identified as integration between concept maps and blogs. Nine graduate students
participated in the study for a semester. Data analysis included examining concept maps for knowledge integration over time.
Participants’ various mapping activities implied different levels of thinking. Some participants’ final concept maps showed
signs that they tried to integrate knowledge around the content area. Yet, the inconsistent and inconclusive patterns of participants’
concept mapping activities signaled that more strategies were needed to sustain their commitment. 相似文献
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77.
Impact of Chronic Lead Exposure on Selected Biological Markers 总被引:1,自引:0,他引:1
Ambica P. Jangid P. J. John D. Yadav Sandhya Mishra Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2012,27(1):83-89
Lead poisoning remains a major problem in India due to the lack of awareness of its ill effects among the clinical community.
Blood lead, δ-aminolevulinic acid dehydratase (δ-ALAD) and zinc protoporphyrin (ZPP) concentrations are widely used as biomarkers
for lead toxicity The present study was designed to determine the impact of chronic lead exposure on selected biological markers.
A total of 250 subjects, of both sexes, ranging in age from 20 to 70 years, were recruited. On the basis of BLLs, the subjects
were categorized into four groups: Group A (BLL: 0–10 μg/dl), Group B (BLL: 10–20 μg/dl). Group C (BLL: 20–30 μg/dl) and Group
D (BLL: 30–40 μg/dl) having BLLs of 3.60 ± 2.71 μg/dl, 15.21 ± 2.65 μg/dl, 26.82 ± 2.53 μg/dl and 36.38 ± 2.83 μg/dl, respectively.
Significant changes in biological markers due to elevated BLLs were noted. The relation of BLL and biological markers to demographic
characteristics such as sex, habits, diet and substances abuse (smoking effect) were also studied in the present investigation.
Males, urban population, non-vegetarians, and smokers had higher blood lead levels. δ-ALAD activity was found to be significantly
lower with increased BLL (P < 0.001), while the ZPP level was significantly higher with increased BLL (P < 0.001). Further, BLL showed a negative correlation with δ-ALAD (r = −0.425, P < 0.001, N = 250) and a positive correlations with ZPP (r = 0.669, P < 0.001, N = 250). Chronic lead exposure affects the prooxidant-antioxidant equilibrium leading to cellular oxidative stress. 相似文献
78.
Rapid extinction of species is one of the most serious ecological problems faced by humanity today. Species are disappearing
at a pace unprecedented in the history of the planet putting the very future of life at risk. The irony is that the root of
the crisis is another species, Homo sapiens rather than some physical events that is poised to threaten its own survival. This article gives a brief introduction to
the crisis, its consequences and possible mitigation strategies. 相似文献
79.
Alannah K. A. McKay David B. Pyne Peter Peeling Avish P. Sharma Megan L.R. Ross Louise M. Burke 《Journal of sports sciences》2019,37(5):553-559
Carbohydrate (CHO) availability could alter mucosal immune responses to exercise. This study compared the effect of three dietary approaches to CHO availability on resting and post-exercise s-IgA levels. Elite race walkers (n = 26) adhered to a high CHO diet (HCHO), periodised CHO availability (PCHO) or a low CHO/high fat diet (LCHF) for 3 weeks while completing an intensified training program. HCHO and PCHO groups consumed 8.0–8.5 g.kg?1 CHO daily, with timing of ingestion manipulated to alter CHO availability around key training sessions. The LCHF diet comprised 80% fat and restricted CHO to < 50 g.day?1. A race walk test protocol (19 km females, 25 km males) was completed at baseline, after adaptation, and following CHO restoration. On each occasion, saliva samples were obtained pre- and post-exercise to quantify s-IgA levels. Resting s-IgA secretion rate substantially increased ~ two-fold post-intervention in all groups (HCHO: 2.2 ± 2.2, PCHO: 2.8 ± 3.2, LCHF: 1.6 ± 1.6; fold-change± 95% confidence limits), however, no substantial differences between dietary treatments were evident. Post-exercise, substantial 20–130% increases in s-IgA concentration and 43–64% reductions in flow rate occurred in all dietary treatments, with trivial differences evident between groups. It appears that high volume training overrides any effect of manipulating CHO availability on mucosal immunity in elite athletes. 相似文献
80.
Vanita Sharma 《Cultural and Social History》2013,10(4):411-428
ABSTRACTThis article explores the creation and transmission of second generation memories concerning the 1947 Partition of British India. The research is based on oral interviews with Punjabi families who migrated because of Partition and now live in Lahore and Delhi. It explores how Partition memories have been transmitted across generations within these families, and also examines similarities and differences between how the second generation interviewees from Delhi and Lahore remember Partition. It demonstrates that the second generation have not passively accepted everything that the first generation, or the state, has told them about Partition. The second generation's memories are also shaped by their age, nationality, religion and class, and the nature of contemporary politics. 相似文献