738 research outputs found

    THE EFFECT OF TWO DIFFERENT WEIGHTED BADMINTON RACKETS ABOUT VELOCITY AND TORQUE WHEN OUTSTANDING BADMINTON PLAYERS WAS PERFORMING SMASH MOVEMENT

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    The purpose of this research is to study and to analyze the relationship of the velocity and torque between two different weighted badminton rackets while the elite players was performing the smash movement .All the data of this study is filmed by digital video (60Hz/s) and is analyzed on the space of 20 by sagittal plane and horizontal axis movement of the participator .In order to derive \rom the primary parameters of smash motion, including velocity, movement of inertia, angular acceleration, torque. The data are digitized and filtered in APAS (the Ariel Performance Analyze System). As a result, by T-Test, the T-values are up to the observable level ,and the level a is 0.05

    S-Petasin, the Main Sesquiterpene of Petasites formosanus, Inhibits Phosphodiesterase Activity and Suppresses Ovalbumin-Induced Airway Hyperresponsiveness

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    S-Petasin is the main sesquiterpene of Petasites formosanus, a traditional folk medicine used to treat hypertension, tumors and asthma in Taiwan. The aim of the present study was to investigate its inhibitory effects on phosphodiesterase (PDE) 1–5, and on ovalbumin (OVA)-induced airway hyperresponsiveness (AHR) in a murine model of allergic asthma. S-Petasin concentration-dependently inhibited PDE3 and PDE4 activities with 50% inhibitory concentrations (IC50) of 25.5, and 17.5 μM, respectively. According to the Lineweaver-Burk analysis, S-petasin competitively inhibited PDE3 and PDE4 activities with respective dissociation constants for inhibitor binding (Ki) of 25.3 and 18.1 μM, respectively. Both IC50 and Ki values for PDE3 were significantly greater than those for PDE4. S-Petasin (10–30 μmol/kg, administered subcutaneously (s.c.)) dose-dependently and significantly attenuated the enhanced pause (Penh) value induced by methacholine (MCh) in sensitized and challenged mice. It also significantly suppressed the increases in total inflammatory cells, lymphocytes, neutrophils, eosinophils and levels of cytokines, including interleukin (IL)-2, IL-4 and IL-5, tumor necrosis factor (TNF)-α and interferon (IFN)-γ in bronchoalveolar lavage fluid (BALF) of these mice. In addition, S-petasin (10–30 μmol/kg, s.c.) dose-dependently and significantly attenuated total and OVA-specific immunoglobulin E (IgE) levels in the serum and BALF, and enhanced the IgG2a level in serum of these mice. The PDE4H value of S-petasin was >300 μM; therefore, its PDE4H/PDE4L value was calculated to be >17. In conclusion, the present results for S-petasin at least partially explain why Petasites formosanus is used as a folk medicine to treat asthma in Taiwan

    The modality effect in a mobile learning environment: Learning from spoken text and real objects

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    The finding that under split-attention conditions students learn more from a picture and spoken text than from a picture and written text (ie, the modality effect) has consistently been found in many types of computer-assisted multimedia learning environments. Using 58 fifth-grade and sixth-grade elementary school children as participants, we investigated whether the modality effect can also be found in a mobile learning environment (MLE) on plants' leaf morphology, in which students had to learn by integrating information from text and real plants in the physical environment. A single factor experimental design was used to examine the hypothesis that students in a mixed-mode condition with real plants and spoken text (STP condition) would pay more attention to the real plants, and achieve higher performance on retention, comprehension, and transfer tests than the single-mode condition with real plants and written text (WTP condition). Whereas we found that participants in the STP condition paid more attention to observing the plants, and achieved a higher score on the transfer test than participants in the WTP condition, no differences were found between the conditions for retention and comprehension test performance

    Assessing the Decision-Making Process in Human-Robot Collaboration Using a Lego-like EEG Headset

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    Human-robot collaboration (HRC) has become an emerging field, where the use of a robotic agent has been shifted from a supportive machine to a decision-making collaborator. A variety of factors can influence the effectiveness of decision-making processes during HRC, including the system-related (e.g., robot capability) and human-related (e.g., individual knowledgeability) factors. As a variety of contextual factors can significantly impact the human-robot decision-making process in collaborative contexts, the present study adopts a Lego-like EEG headset to collect and examine human brain activities and utilizes multiple questionnaires to evaluate participants’ cognitive perceptions toward the robot. A user study was conducted where two levels of robot capabilities (high vs. low) were manipulated to provide system recommendations. The participants were also identified into two groups based on their computational thinking (CT) ability. The EEG results revealed that different levels of CT abilities trigger different brainwaves, and the participants’ trust calibration of the robot also varies the resultant brain activities

    Recent Development of Graphene-Based Cathode Materials for Dye-Sensitized Solar Cells

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    Dye-sensitized solar cells (DSSCs) have attracted extensive attention for serving as potential low-cost alternatives to silicon-based solar cells. As a vital role of a typical DSSC, the counter electrode (CE) is generally employed to collect electrons via the external circuit and speed up the reduction reaction of I3- to I- in the redox electrolyte. The noble Pt is usually deposited on a conductive glass substrate as CE material due to its excellent electrical conductivity, electrocatalytic activity, and electrochemical stability. To achieve cost-efficient DSSCs, reasonable efforts have been made to explore Pt-free alternatives. Recently, the graphene-based CEs have been intensively investigated to replace the high-cost noble Pt CE. In this paper, we provided an overview of studies on the electrochemical and photovoltaic characteristics of graphene-based CEs, including graphene, graphene/Pt, graphene/carbon materials, graphene/conducting polymers, and graphene/inorganic compounds. We also summarize the design and advantages of each graphene-based material and provide the possible directions for designing new graphene-based catalysts in future research for high-performance and low-cost DSSCs

    A large-scale survey of genetic copy number variations among Han Chinese residing in Taiwan

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    <p>Abstract</p> <p>Background</p> <p>Copy number variations (CNVs) have recently been recognized as important structural variations in the human genome. CNVs can affect gene expression and thus may contribute to phenotypic differences. The copy number inferring tool (CNIT) is an effective hidden Markov model-based algorithm for estimating allele-specific copy number and predicting chromosomal alterations from single nucleotide polymorphism microarrays. The CNIT algorithm, which was constructed using data from 270 HapMap multi-ethnic individuals, was applied to identify CNVs from 300 unrelated Han Chinese individuals in Taiwan.</p> <p>Results</p> <p>Using stringent selection criteria, 230 regions with variable copy numbers were identified in the Han Chinese population; 133 (57.83%) had been reported previously, 64 displayed greater than 1% CNV allele frequency. The average size of the CNV regions was 322 kb (ranging from 1.48 kb to 5.68 Mb) and covered a total of 2.47% of the human genome. A total of 196 of the CNV regions were simple deletions and 27 were simple amplifications. There were 449 genes and 5 microRNAs within these CNV regions; some of these genes are known to be associated with diseases.</p> <p>Conclusion</p> <p>The identified CNVs are characteristic of the Han Chinese population and should be considered when genetic studies are conducted. The CNV distribution in the human genome is still poorly characterized, and there is much diversity among different ethnic populations.</p

    Observational connection of non-thermal X-ray emission from pulsars with their timing properties and thermal emission

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    The origin and radiation mechanisms of high energy emissions from pulsars have remained mysterious since their discovery. Here we report, based on a sample of 68 pulsars, observational connection of non-thermal X-ray emissions from pulsars with their timing properties and thermal emissions, which may provide some constraints on theoretical modeling. Besides strong correlations with the spin-down power E˙\dot{E} and the magnetic field strength at the light cylinder BlcB_{\rm lc}, the non-thermal X-ray luminosity in 0.5 - 8 keV, LpL_{\rm p}, represented by the power-law component in the spectral model, is found to be strongly correlated with the highest possible electric field strength in the polar gap, EpcE_{\rm pc}, of the pulsar. The spectral power index Γp\Gamma_{\rm p} of that power-law component is also found, for the first time in the literature, to strongly correlate with E˙\dot{E}, BlcB_{\rm lc} and EpcE_{\rm pc}, thanks to the large sample. In addition, we found that LpL_{\rm p} can be well described by LpT5.96±0.64R2.24±0.18L_{\rm p}\propto T^{5.96\pm 0.64}R^{2.24\pm 0.18}, where TT and RR are the surface temperature and the emitting-region radius of the surface thermal emission, represented by the black-body component in the spectral model. Γp\Gamma_{\rm p}, on the other hand, can be well described only when timing variables are included, and the relation is Γp=log(T5.8±1.93R2.29±0.85P1.19±0.88P˙0.94±0.44)\Gamma_{\rm p} = \log(T^{-5.8\pm 1.93}R^{-2.29\pm 0.85}P^{-1.19\pm 0.88}\dot{P}^{0.94\pm 0.44}) plus a constant. These relations strongly suggest the existence of connections between surface thermal emission and electron-positron pair production in pulsar magnetospheres.Comment: 13 pages, 11 figures, accepted by MNRA
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