1,497 research outputs found
LEVERAGING SPORTING EQUIPMENT BALANCE AND WEIGHT DISTRUBUTION INFLUENCE ON PUTTING KINEMATICS –A STUDY ON COUNTER-BALANCED PUTTER DESIGN
In golf, putting is considered one of the most important factors for scoring of professional Tour players (Alexander & Kern, 2005), and accounts for 43% ± 2% per round (Pelz & Frank, 2000). Unlike the long game, short game like putting, is focused on its accuracy and consistency (Hume, Keogh & Reid, 2005). Putting stroke requires accurate and repeatable stroke especially during impact stage, and one of the most recent putter design is to grip down or to have extra weights on the grip end of the club, also known as the counterbalanced putter
THE BIOMECHANICAL ANALYSIS OF THE TAEKWONDO FRONT-LEG AXE-KICK
The purpose of the study was to analyze the biomechanics of taekwondo front-leg axekick. One force plates, two synchronized high-speed cameras were used to measure biomechanical parameters in each phase of the front-leg axe-kick. The results included: 1. The average reaction time and movement time were 0.423 sand 0.327 s, which respectively occupied about 56% and 44% of attack time. 2. The maximum velocity of hip, knee and ankle were 1.74 m/s, 5.25 m/s and 7.43 m/s respectively. When the kicking leg touched the target, the velocity of knee and ankle were 0.78m/s, 1.72m1s, and 4.64m1s respectively. 3. The peak vertical GRF and impulse were 0.96 SW and 77.57N-s. For decreasing the movement time, it's suggested that an athlete should increase the power and flexibility of lower extremities during the training section
MCRS2 represses the transactivation activities of Nrf1
<p>Abstract</p> <p>Background</p> <p>Nrf1 [p45 nuclear factor-erythroid 2 (p45 NF-E2)-related factor 1], a member of the CNC-bZIP (CNC basic region leucine zipper) family, is known to be a transcriptional activator by dimerization with distinct partners, such as Maf, FosB, c-Jun, JunD, etc. The transcriptional roles of CNC-bZIP family are demonstrated to be involved in globin gene expression as well as the antioxidant response. For example, CNC-bZIP factors can regulate the expression of detoxification proteins through AREs, such as expression of human gamma-glutamylcysteine synthetases (GCS), glutathione S-transferases (GST), UDP-glucuronosyl transferase (UDP-GT), NADP (H) quinone oxidoreductase (NQOs), etc. To further explore other factor(s) in cells related to the function of Nrf1, we performed a yeast two-hybrid screening assay to identify any Nrf1-interacting proteins. In this study, we isolated a cDNA encoding residues 126–475 of MCRS2 from the HeLa cell cDNA library. Some functions of MCRS1 and its splice variant-MSP58 and MCRS2 have been previously identified, such as transforming, nucleolar sequestration, ribosomal gene regulation, telomerase inhibition activities, etc. Here, we demonstrated MCRS2 can function as a repressor on the Nrf1-mediated transactivation using both in vitro and in vivo systems.</p> <p>Results</p> <p>To find other proteins interacting with the CNC bZIP domain of Nrf1, the CNC-bZIP region of Nrf1 was used as a bait in a yeast two-hybrid screening assay. MCRS2, a splicing variant of p78/MCRS1, was isolated as the Nrf1-interacting partner from the screenings. The interaction between Nrf1 and MCRS2 was confirmed <it>in vitro </it>by GST pull-down assays and <it>in vivo </it>by co-immunoprecipitation. Further, the Nrf1-MCRS2 interaction domains were mapped to the residues 354–447 of Nrf1 as well as the residues 314–475 of MCRS2 respectively, by yeast two-hybrid and GST pull-down assays. By immunofluorescence, MCRS2-FLAG was shown to colocalize with HA-Nrf1 in the nucleus and didn't result in the redistribution of Nrf1. This suggested the existence of Nrf1-MCRS2 complex in vivo. To further confirm the biological function, a reporter driven by CNC-bZIP protein binding sites was also shown to be repressed by MCRS2 in a transient transfection assay. An artificial reporter gene activated by LexA-Nrf1 was also specifically repressed by MCRS2.</p> <p>Conclusion</p> <p>From the results, we showed MCRS2, a new Nrf1-interacting protein, has a repression effect on Nrf1-mediated transcriptional activation. This was the first ever identified repressor protein related to Nrf1 transactivation.</p
Scaly Ear Rash as the Herald of a Young Girl with Juvenile Systemic Lupus Erythematosus
Juvenile systemic lupus erythematosus (JSLE) is an autoimmune-mediated multiorgan disease. The cutaneous manifestation is one of the most common initial presentations in JSLE. A typical lesion is a facial malar rash, but a patient may sometimes present with nonclassical lesions. Herein, we report two cases of JSLE with similar persistent scaly ear rashes as the heralding cutaneous symptom preceding systemic symptoms. Identifying this atypical and underestimated cutaneous rash in juvenile patients might help the clinician make the correct diagnosis and provide earlier intervention, which may help prevent disease progression
A dynamic model of auctions with buy-it-now: theory and evidence
In the ascending-price auctions with Yahoo!-type buy-it-now (BIN), we characterize and
derive the closed-form solution for the optimal bidding strategy of the bidder and the optimal
BIN price of the seller when they are both risk-averse. The seller is shown to be strictly
better o with the BIN option, while the bidders are better o only when their valuation is
greater than a threshold value. The theory also implies that the expected transaction price
is higher in an auction with an optimal BIN price than one without a BIN. This prediction
is conrmed by our data collected from Taiwan's Yahoo! auctions of Nikon digital cameras
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