11,197 research outputs found
DIFFERENCES BETWEEN MALE AND FEMALE PLAYERS IN THE FRONTAL PLANE BIOMECHANICS DURING VOLLEYBALL SPIKE LANDING
The purpose of this study was to investigate differences of kinematic variables between male and female volleyball players after a spiking, to understand the mechanism of volleyball spike landing. Eight males and eight females were recruited to participate in this study from the university volleyball team. The kinematic data were collected by ten Vicon cameras (300Hz) and two force plates (1500Hz). The results presented the right hip joint, and both knee joints are significant differences between male and female volleyball players at initial contact. Similarly, at the moment of peak force during the landing phase, the right hip joint and both knee joints are significant differences between male and female volleyball players. These differences demonstrated that male and female players performed different strategies during volleyball spike landing
Structural characterization of the Fddd phase in a diblock copolymer thin film by electron microtomography
A 3-dimensional Fddd network structure of a polystyrene-block-polyisoprene (PS-b-PI) diblock copolymer (M(n) = 31 500, f(PI) = 0.645) was observed for the first time in real space by transmission electron microtomography (TEMT). In a 650 nm thick film of the PS-b-PI thin film on a silicon wafer, the Fddd phase was developed after annealing at 215 degrees C for 24 h. The single network structure consists of the connected tripodal units of minor PS block domains. The {111}(Fddd) plane, the densest plane of the minor PS phase, was found to orient parallel to the film plane. The transitional structure from the wetting layer at the free surface to the internal {111}(Fddd) plane via a perforated layer structure was also observed.X111313sciescopu
Nanomechanical Properties and Deformation Behaviors of Multi-Component (AlCrTaTiZr)NxSiy High-Entropy Coatings
The Enterprise Risk Management of Foreign Exchange Exposures: Evidence from Taiwanese Hospitality Industry
For this paper, I use the ARIMA model to study the relationship between business performance and exchange rate fluctuations. Through this model, the empirical results shows that the influences of foreign exchange rate fluctuations on the tourist hotel business performance are significant and different across currencies and firms. Furthermore, according to the framework of Kim (2013) we employ the modern portfolio theory proposed by Markowitz (1952) to give an optimal foreign exchange allocation for each tourist hotel company's financial decision-makers, which will avoid the risk of exchange rate fluctuations expose and reduce losses due to the fluctuations of exchange rates, and complete the construction of enterprise risk management system (ERM)
Moisture-triggered physically transient electronics
Physically transient electronics, a form of electronics that can physically disappear in a controllable manner, is very promising for emerging applications. Most of the transient processes reported so far only occur in aqueous solutions or biofluids, offering limited control over the triggering and degradation processes. We report novel moisture-triggered physically transient electronics, which exempt the needs of resorption solutions and can completely disappear within well-controlled time frames. The triggered transient process starts with the hydrolysis of the polyanhydride substrate in the presence of trace amounts of moisture in the air, a process that can generate products of corrosive organic acids to digest various inorganic electronic materials and components. Polyanhydride is the only example of polymer that undergoes surface erosion, a distinct feature that enables stable operation of the functional devices over a predefined time frame. Clear advantages of this novel triggered transience mode include that the lifetime of the devices can be precisely controlled by varying the moisture levels and changing the composition of the polymer substrate. The transience time scale can be tuned from days to weeks. Various transient devices, ranging from passive electronics (such as antenna, resistor, and capacitor) to active electronics ( such as transistor, diodes, optoelectronics, and memories), and an integrated system as a platform demonstration have been developed to illustrate the concept and verify the feasibility of this design strategy
Transcription of the rat testis-specific Rtdpoz-T1 and -T2 retrogenes during embryo development: co-transcription and frequent exonisation of transposable element sequences
<p>Abstract</p> <p>Background</p> <p>Retrotransposition is an important evolutionary force for the creation of new and potentially functional intronless genes which are collectively called retrogenes. Many retrogenes are expressed in the testis and the gene products have been shown to actively participate in spermatogenesis and other unique functions of the male germline. We have previously reported a cluster of retrogenes in the rat genome that encode putative TRAF- and POZ-domain proteins. Two of the genes, <it>Rtdpoz-T1 and -T2 </it>(abbreviated as <it>T1 </it>and <it>T2</it>), have further been shown to be expressed specifically in the rat testis.</p> <p>Results</p> <p>We show here that the <it>T1 </it>and <it>T2 </it>genes are also expressed in the rat embryo up to days 16–17 of development when the genes are silenced until being re-activated in the adult testis. On database interrogation, we find that some <it>T1/T2 </it>exons are chromosomally duplicated as cassettes of 2 or 3 exons consistent with retro-duplication. The embryonic <it>T1/T2 </it>transcripts, characterised by RT-PCR-cloning and rapid amplification of cDNA ends, are further found to have acquired one or more noncoding exons in the 5'-untranslated region (5'-UTR). Most importantly, the <it>T1</it>/<it>T2 </it>locus is embedded within a dense field of relics of transposable element (TE) derived mainly from LINE1 and ERV sequences, and the TE sequences are frequently exonised through alternative splicing to form the 5'-UTR sequences of the <it>T1/T2 </it>transcripts. In a case of <it>T1 </it>transcript, the 3'-end is extended into and terminated within an L1 sequence. Since the two genes share a common exon 1 and are, therefore, regulated by a single promoter, a <it>T2</it>-to-<it>T1 </it>co-transcription model is proposed. We further demonstrate that the exonised 5'-UTR TE sequences could lead to the creation of upstream open reading frames resulting in translational repression.</p> <p>Conclusion</p> <p>Exonisation of TE sequences is a frequent event in the transcription of retrogenes during embryonic development and in the testis and may contribute to post-transcriptional regulation of expression of retrogenes.</p
- …