1,736 research outputs found
The Influence of Intermediate Intensity Intermittent Cycle Training on College Students’ Fitness
Australia F45 functional training is a high-intensity intermittent cycle training method, integrating life, interest, competitiveness and cooperation together. The purpose of this study was to examine the effect of this training method on college students’ physical quality. 30 Participants from a university in southwest of China were recruited and were divided into two groups. The control group used traditional training methods while the experimental group used indirect circular training method, moderate intensity (pulse control at an average of 140-160 times / min), with the cooperation of music training. The corresponding fitness was tested before and 6 weeks after the experiment. Before and after the experiment, the scores of 50m, standing long jump, pull up / sit up, sitting forward, 800m / 1000m were tested respectively. The content of classroom training was composed of the auxiliary training contents of the five qualities: high leg lifting, small step running, frog jump, upright jump, push-up, flat support, standing forward and so on. The fitness of the students in the control group and the experimental group was improved, and the improvement of the experimental group was more obvious, especially the standing long jump, sit ups and long-distance running. It is suggested that college students accept the medium intensity intermittent cycle training method, which can improve the physical quality of college students
The comparative effectiveness of mobile phone interventions in improving health outcomes: Meta-analytic review
Background: As mobile technology continues expanding, researchers have been using mobile phones to conduct health interventions (mobile health-mHealth-interventions). The multiple features of mobile phones offer great opportunities to disseminate large-scale, cost-efficient, and tailored messages to participants. However, the interventions to date have shown mixed results, with a large variance of effect sizes (Cohen d=-0.62 to 1.65).
Objective: The study aimed to generate cumulative knowledge that informs mHealth intervention research. The aims were twofold: (1) to calculate an overall effect magnitude for mHealth interventions compared with alternative interventions or conditions, and (2) to analyze potential moderators of mHealth interventions\u27 comparative efficacy.
Methods: Comprehensive searches of the Communication & Mass Media Complete, PsycINFO, Web of Knowledge, Academic Search Premier, PubMed and MEDLINE databases were conducted to identify potentially eligible studies in peer-reviewed journals, conference proceedings, and dissertations and theses. Search queries were formulated using a combination of search terms: intervention (Title or Abstract) AND health (Title or Abstract) AND *phone* OR black-berr* (OR mHealth OR application* OR app* OR mobile OR cellular OR short messag* OR palm* OR iPhone* OR MP3* OR MP4* OR iPod*) (Title or Abstract). Cohen d was computed as the basic unit of analysis, and the variance-weighted analysis was implemented to compute the overall effect size under a random-effects model. Analysis of variance-like and meta-regression models were conducted to analyze categorical and continuous moderators, respectively.
Results: The search resulted in 3424 potential studies, the abstracts (and full text, as necessary) of which were reviewed for relevance. Studies were screened in multiple stages using explicit inclusion and exclusion criteria, and citations were evaluated for inclusion of qualified studies. A total of 64 studies were included in the current meta-analysis. Results showed that mHealth interventions are relatively more effective than comparison interventions or conditions, with a small but significant overall weighted effect size (Cohen d=0.31). In addition, the effects of interventions are moderated by theoretical paradigm, 3 engagement types (ie, changing personal environment, reinforcement tracking, social presentation), mobile use type, intervention channel, and length of follow-up.
Conclusions: To the best of our knowledge, this is the most comprehensive meta-analysis to date that examined the overall effectiveness of mHealth interventions across health topics and is the first study that statistically tested moderators. Our findings not only shed light on intervention design using mobile phones, but also provide new directions for research in health communication and promotion using new media. Future research scholarship is needed to examine the effectiveness of mHealth interventions across various health issues, especially those that have not yet been investigated (eg, substance use, sexual health), engaging participants using social features on mobile phones, and designing tailored mHealth interventions for diverse subpopulations to maximize effects
Solid-Phase Extraction Combined with High Performance Liquid Chromatography-Diode Array Detector for Rapid Determination of Estrogens in Milk
Purpose: To develop a simple but effective method for the quantitative analysis of estrogens in milk.Methods: Solid-phase extraction method was employed for the extraction of the estrogen from milk and high performance liquid chromatography-diode array detector (HPLC-DAD) was used for the determination of estrogen.Results: Optimal chromatographic conditions were achieved on an Eclipse XDB-C18 column at a flow rate of 0.8 mL/min at room temperature. The products were monitored using a DAD detector set at 280 nm. The retention time of the three main estrogens were 15 min with a gradient program of acetonitrile/water, from 0 to 3 min, holding 35 % acetonitrile; from 4 to 7 min, ramped to 55 % acetonitrile; from 8 to 20 min, maintained at 55 % acetonitrile. The results showed that the calibration curve had good linearity within the concentration range of 0.5 - 8.0 μg/mL with correlation coefficient (R2) in the range of 0.9929-0.9936. The limit of detection was in the range of 0.025 - 0.045 μg/mL while mean recovery of estrogen from milk samples varied from 92.6 to 104.1 %. Satisfactory precision was obtained both for intra-assay (RSD, 1.8 to 4.4 %) and inter-assay (RSD, 2.0 to 4.7 %).Conclusion: The proposed method is environmentally friendly, inexpensive and convenient, and should be helpful in analyzing estrogens in biological, environmental and food samples.Keywords: Solid-phase extraction, Milk, Estrogens, High performance liquid chromatography-diode array detecto
MOLECULAR ANALYSIS OF THE ROLE OF YEAST MITOCHONDRIAL PROTEIN QCR7P IN AGROBACTERIUM-YEAST DNA TRANSFER
Ph.DDOCTOR OF PHILOSOPH
Three dimensional photonic Dirac points in metamaterials
Topological semimetals, representing a new topological phase that lacks a
full bandgap in bulk states and exhibiting nontrivial topological orders,
recently have been extended to photonic systems, predominantly in photonic
crystals and to a lesser extent, metamaterials. Photonic crystal realizations
of Dirac degeneracies are protected by various space symmetries, where Bloch
modes span the spin and orbital subspaces. Here, we theoretically show that
Dirac points can also be realized in effective media through the intrinsic
degrees of freedom in electromagnetism under electromagnetic duality. A pair of
spin polarized Fermi arc like surface states is observed at the interface
between air and the Dirac metamaterials. These surface states show linear
k-space dispersion relation, resulting in nearly diffraction-less propagation.
Furthermore, eigen reflection fields show the decomposition from a Dirac point
to two Weyl points. We also find the topological correlation between a Dirac
point and vortex/vector beams in classic photonics. The theoretical proposal of
photonic Dirac point lays foundation for unveiling the connection between
intrinsic physics and global topology in electromagnetism.Comment: 15 pages, 5 figure
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