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Medium perfusion is critical in maintaining high cell concentration in cultures. The conventional membrane filtration method for medium exchange has been challenged by the fouling and clogging of the membrane filters in long-term cultures. In this study, we present a miniature auto-perfusion system that can be operated inside a common-size laboratory incubator. The system is equipped with a spiral microfluidic chip for cell retention to replace conventional membrane filters, which fundamentally overcomes the clogging and fouling problem. We showed that the system supported continuous perfusion culture of Chinese hamster ovary (CHO) cells in suspension up to 14 days without cell retention chip replacement. Compared to daily manual medium change, 25% higher CHO cell concentration can be maintained at an average auto-perfusion rate of 196 ml/day in spinner flask at 70 ml working volume (2.8 VVD). The auto-perfusion system also resulted in better cell quality at high concentrations, in terms of higher viability, more uniform and regular morphology, and fewer aggregates. We also demonstrated the potential application of the system for culturing mesenchymal stem cells on microcarriers. This miniature auto-perfusion system provides an excellent solution to maintain cell-favorable conditions and high cell concentration in small-scale cultures for research and clinical uses.

The drug-induced diverse response among patients is a severe problem for improving hemorheological character. However, there is no validated method for personalized therapy to the best of our knowledge. Here, we apply a gravity-driven deformability cytometry platform (GD-DCP) to profile the drug response of the red cell deformability (RCD) at the single-cell level using pentoxifylline (PTX) as a model drug, the effect of different concentrations of PTX (0, 2, 20, 200 μg mL

We present a new and simple method to improve internal light out-coupling of organic light emitting diodes (OLEDs) by incorporating tungsten trioxide (WO3) islands or network structure in the devices. These structures were pattern-transferred from a cesium chloride (CsCl) film that self-assembled into the islands or network structure as it deliquesced in air. The size and type of structures could be controlled with the thickness of the CsCl film, the relative humidity, the developing time and the developing temperature. The WO3 patterned structures scattered light in the OLEDs devices to extract light trapped in the waveguide modes. As a result, the current efficiencies, external quantum efficiencies and power efficiencies of the WO3 patterned OLEDs were increased compared with those of a conventional OLED without WO3 layer. Operating voltages of the devices with WO3 layer were significantly decreased because the WO3 layer facelifted the hole injection of the devices.

Mesenchymal stem cells (MSCs) have the capability to differentiate into multiple cell lineages, and produce trophic factors to facilitate tissue repair and regeneration, and disease regression. However, the heterogeneity of MSCs, whether inherent or developed during culture expansion, has a significant impact on their therapeutic efficacy. Therefore, the ability to identify and select an efficacious subpopulation of MSCs targeting specific tissue damage or disease holds great clinical significance. In this study, we separated three subpopulations from culture expanded human bone marrow derived MSCs according to cell size, using a high-throughput label-free microfluidic cell sorting technology. The size-sorted MSC subpopulations varied in tri-lineage differentiation potencies. The large MSCs showed the strongest osteogenesis, medium-size MSCs were advantageous in chondrogenesis and adipogenesis, and the small MSCs showed the weakest tri-lineage differentiation. The size-sorted MSC subpopulations also exhibited different secretome profiles. The large MSC secretome possessed highest levels of osteogenic promotor proteins and senescence-associated factors, but lower levels of osteogenic inhibitor proteins compared to the medium-size MSC secretome. The medium-size MSC secretome had high levels of chondrogenic promotor proteins, and contained lower levels of chondrogenic inhibitor proteins compared to the large MSC secretome. The secretome of size-sorted MSC subpopulations showed differences in paracrine effects. We found that the secretome of large MSCs enhanced osteogenic and adipogenic potencies during MSC culture expansion, but also induced cell senescence; and the secretome of medium-size MSCs promoted chondrogenesis. This study demonstrates size-dependent differentiation potency and secretome profile of MSC subpopulations, and provides an effective and practical technology to isolate the respective subpopulations, which may be used for more targeted tissue repair and regeneration.

In Bayesian decision theory, knowledge about the probabilities of possible outcomes is captured by a prior distribution and a likelihood function. The prior reflects past knowledge and the likelihood summarizes current sensory information. The two combined (integrated) form a posterior distribution that allows estimation of the probability of different possible outcomes. In this study, we investigated the neural mechanisms underlying Bayesian integration using a novel lottery decision task in which both prior knowledge and likelihood information about reward probability were systematically manipulated on a trial-by-trial basis. Consistent with Bayesian integration, as sample size increased, subjects tended to weigh likelihood information more compared with prior information. Using fMRI in humans, we found that the medial prefrontal cortex (mPFC) correlated with the mean of the posterior distribution, a statistic that reflects the integration of prior knowledge and likelihood of reward probability. Subsequent analysis revealed that both prior and likelihood information were represented in mPFC and that the neural representations of prior and likelihood in mPFC reflected changes in the behaviorally estimated weights assigned to these different sources of information in response to changes in the environment. Together, these results establish the role of mPFC in prior-likelihood integration and highlight its involvement in representing and integrating these distinct sources of information.

Sports fans and participants have shown increasing interest in traveling overseas for sport tourism. When sports tourists visit sports destinations, the tourists not only spend money on events and games but also bring additional revenue to local businesses. The major purpose of this study was to investigate factors that might influence international sports fans' intention to travel to the United States for sport tourism. A survey with 49 questions was distributed to 500 college students in Taiwan. The results of exploratory factor analysis show that six factors (cost and ease of arranging travel plans, interest in professional sports, different cultural experience, interest in travel, experience of watching live sporting events, and the chance to see Asian players or famous US players in the games) are the major factors that influence international fans' intention to travel to the United States for sport tourism. The results of this study will be helpful for sport management professionals to understand in...

Asian female athletes' prominent performances have caught the media's attention for coverage. Despite the success of Asian female athletes, stereotypes and expectations of feminine characteristics towards female athletes may still exist, especially in Asia where there is long history of a male-dominated society. The major purpose of this study was to gain an understanding of how the media covers Asian female Olympic athletes and to see if sports writers emphasize feminine characteristics in news coverage when reporting Asian female Olympic athletes. Content analysis was administered to review news stories of Asian female Olympic athletes who were reported in 266 sport news articles from 1 January 2000 to 31 August 2008. The results indicated that sports such as diving and the marathon are more likely to be covered although Asian female Olympic athletes have been successful in other sports. Topics and content related to athletes' achievements in sports, physical/athletic strength, and psychological characteristics were frequently included in the news stories.

Stripping crystallization (SC), also called distillative freezing (DF), is introduced to separate the benzene (Bz)/cyclohexane (Cx) mixture. In principle, SC is operated at a triple-point condition, in which the liquid mixture is simultaneously vaporized and crystallized due to the three-phase equilibrium. Thus, SC combines distillation and crystallization to produce pure crystals. The experiments show that three SC operations are required to purify Cx ( B ) from X W , B = 0.907 to X W , B = 0.996 in the Cx-rich mixture. On the other hand, only one SC operation is required to purify Bz ( A ) mixture from X W , A = 0.893 to X W , A = 0.999 in the Bz-rich mixture. Thus, it is easier to separate Bz from the Bz-rich mixture than to separate Cx from the Cx-rich mixture. These experimental results are consistent with the simulations predicted by the proposed model.

Web advertising has become one of the popular forms for corporations to reach their target markets. Thus, an increasing number of sports organizations are using their web site as a medium to communicate with customers or fans. However, there has been little information about the use of web advertising in the sports industry. This study explored the current use of web advertising and the perceptions of professional sports marketers for its potential in terms of both reaching customers and fans and providing additional revenue through sponsorship or other activities. The respondents were marketers from US professional sports bodies. Ultimately the study provides suggestions for sport organizations that are considering utilizing web advertising for revenue purposes.

Objectives To conduct a prospective and randomized trial to compare the efficiency quotient and cost-effectiveness index of shock wave lithotripsy (SWL) and ureteroscopic lithotripsy (URSL) for the treatment of large upper third ureteral stones. Methods A total of 35 male patients and 7 female patients with a solitary, radiopaque upper ureteral stone, 15 mm or more in diameter, who underwent SWL or URSL were enrolled in this study. The mean patient age was 53.1 ± 14.5 years. The endpoint of the study was for the patient to be stone free or to have insignificant residual stone (3 mm or less) within the kidney. Results The mean stone length ± SD was 17.9 ± 3.9 cm in the SWL group and 18.5 ± 2.9 cm in the URSL group (P >0.05). The efficiency quotient for SWL and URSL was 0.61 and 0.63, respectively. The cost-effectiveness index, treatment time, pain score, and hospital stay were greater in the URSL group. However, the degree of hydronephrosis significantly influenced the success rate of SWL. All patients with severe hydronephrosis in the SWL group needed auxiliary surgical procedures to become stone free. Conclusions The efficiency quotients of SWL and URSL were comparable in the treatment of large upper third ureteral stones. However, SWL should not be recommended as the first-line treatment option for the management of upper third ureteral stones larger than 1.5 cm with severe hydronephrosis. Understanding the cost-effectiveness, success rate, pain score, and patient satisfaction score for the two different approaches constitutes the indispensable requisites for choosing the optimal first-line therapeutic strategy.

As the world becomes a global village, sports organisations have begun to extend their markets and fan bases to different groups of customers. David Beckham, a British soccer star with a high profile marriage and much media attention, has endorsed numerous products, thereby becoming an excellent case study for the current trend of athlete endorsement in the international sports industry. The results of this case study provide insights into factors that might influence the success of athlete endorsement.

The world is becoming a global village and within many professions, including physical education and sport, individuals have multiple opportunities to work and socialize with people from different ethnic backgrounds, cultures, lifestyles, religions, etc. Due to the increasing cultural diversity, it is important for physical education and sport professionals to understand how cultural and social factors of different ethnic groups and countries may influence a person from participating in physical activity. The aim of this paper was to examine some of the traditional and recent cultural and social factors that have an impact on women's participation in physical activities in Taiwan. Factors such as changes within the family structure, equal education opportunities, and the growing attention from the government toward physical activity for all have motivated and encouraged women in Taiwan to participate in physical activity. The other aim of this paper was to emphasize the importance of Taiwanese women's phy...

The next-generation retinal prostheses feature high image resolution and chronic implantation. These features demand the delivery of power as high as 100 mW to be wireless and efficient. A common solution is the 2-coil inductive power link, used by current retinal prostheses. This power link tends to include a larger-size extraocular receiver coil coupled to the external transmitter coil, and the receiver coil is connected to the intraocular electrodes through a trans-sclera trans-choroid cable. In the long-term implantation of the device, the cable may cause hypotony (low intraocular pressure) and infection. However, when a 2-coil system is constructed from a small-size intraocular receiver coil, the efficiency drops drastically which may induce over heat dissipation and electromagnetic field exposure. Our previous 2-coil system achieved only 7% power transfer. This paper presents a fully intraocular and highly efficient wireless power transfer system, by introducing another inductive coupling link to bypass the trans-sclera trans-choroid cable. With the specific equivalent load of our customized 512-electrode stimulator, the current 3-coil inductive link was measured to have the overall power transfer efficiency around 36%, with 1-inch separation in saline. The high efficiency will favorably reduce the heat dissipation and electromagnetic field exposure to surrounding human tissues. The effect of the eyeball rotation on the power transfer efficiency was investigated as well. The efficiency can still maintain 14.7% with left and right deflection of 30 degree during normal use. The surgical procedure for the coils' implantation into the porcine eye was also demonstrated.

Much effort has been put into developing multi-channel retinal prosthetic devices. Currently, even the most advanced prostheses do not have enough channels to provide vision to a desirable level. In this paper, we present a system design and a packaging scheme for a 512-channel intraocular epiretinal implant. Both a wireless power coil (with high transfer efficiency) and a data coil are included for this intraocular system. Simulation of the interference between coils is investigated and the results show that the two coils can be put in a co-planar fashion using two notch filters to minimize interference. The complete package is demonstrated with a mechanical model with a parylene-C flexible circuit board, i.e., parylene flex, to show the placement of the IC chips, discrete components, and coils. It also shows the final folded device after surgical insertion into an eye to save space. The feasibility of the proposed structure has been successfully tested in vivo. Experimentally, the maximum allowable pulling force is measured by a dynamic mechanical analysis (DMA) machine to be 8N, which provides a large safety margin for surgery.

Background The association between ischemic stroke and 2 single nucleotide polymorphisms (SNPs) on chromosome 12p13, rs12425791 and rs11833579 appears inconsistent across different samples. These SNPs are close to the ninjurin2 gene which may alter the risk of stroke by affecting brain response to ischemic injury. The purpose of this study was to investigate the association between these two SNPs and ischemic stroke risk, as well as prognostic outcomes in a Taiwanese sample. Methods We examined the relations of these two SNPs to the odds of new-onset ischemic stroke, ischemic stroke subtypes, and to the one year risk of stroke-related death or recurrent stroke following initial stroke in a case-control study. A total of 765 consecutive patients who had first-ever ischemic stroke were compared to 977 stroke-free, age-matched controls. SNPs were genotyped by Taqman fluorescent allelic discrimination assay. The association between ischemic stroke and SNPs were analyzed by multivariate logistic regression. Cox proportional hazard model was used to assess the effect of individual SNPs on stroke-related mortality or recurrent stroke. Results There was no significant association between SNP rs12425791 and rs11833579 and ischemic stroke after multiple testing corrections. However, the marginal significant association was observed between SNP rs12425791 and large artery atherosclerosis under recessive model (OR, 2.30; 95%CI, 1.22-4.34; q-value = 0.062). Among the 765 ischemic stroke patients, 59 died or developed a recurrent stroke. After adjustment for age, sex, vascular risk factors and baseline stroke severity, Cox proportional hazard analysis indicated that the hazard ratios were 2.76 (95%CI, 1.34-5.68; q-value, 0.02) and 2.15 (95%CI, 1.15-4.02; q-value, 0.03) for individuals with homozygous variant allele of rs12425791 and rs11833579, respectively. Conclusions This is a precedent study that found genetic variants of rs12425791 and rs11833579 on chromosome 12p13 are independent predictors of stroke-related mortality or stroke recurrence in patients with incident ischemic stroke in Taiwan. Further study is needed to explore the details of the physiological function and the molecular mechanisms underlying the association of this genetic locus with ischemic stroke.

Following the rapid advances in digital technologies, more and more consumer electronic devices, such as cell phones and PDAs, are equipped with built-in camera modules. In order to be cost-effective, optoelectronics components used in such devices are usually not sophisticated enough to support professional photographing. Pictures taken by such devices tend to be of unsatisfiable quality under poor shooting conditions, and post-processing becomes very useful in improving the quality of such images. Among various post-processing techniques of digital images, histogram equalization performs contrast adjustment of an image by evenly distributing its brightness values. In digital images, however, the phenomenon of ``quantization'' prevents ideal equalization of the histogram. To compensate for such drawback, we propose a technique named Gaussian Distributive Filter to serve as a post-enhancement method for histogram equalization techniques to fine-tune the histogram of an image. Experimental results show our proposed technique to be promising.

In recent years, intelligent vehicles and smart phones have become more and more popular. The traffic sign recognition system is one kind of driving assistance system (DAS) which is used to automatically inform the driver the traffic sign information by a head up display (HUD), monitor, or speaker device. Hence this system is helpful to reduce driver distraction to increase driver safety. In this paper, an efficient real-time traffic sign recognition scheme is proposed for intelligent vehicles. The proposed scheme can integrate in-vehicle computing devices and smart phones to construe an in-vehicle traffic sign recognition system. This scheme contains four major stages: video frame capturing and transmitting, image preprocess, traffic sign detection, and character/icon extraction and recognition. The smart phone first captures videos and then extracts video frames in certain frame-rate. These extracted frames can be transmitted to an in-vehicle computing device by a wireless network (Bluetooth, WiMAX, Wi-Fi etc.) The preprocess employs some image processing to improve and transform the video frames to keep a stable quality for following detection and recognition schemes. At following stages, this paper presents some efficient and accurate traffic sign detection and recognition schemes which contain color selection, shape recognition, character/icon extraction and recognition. The experimental results shows that the proposed scheme only averagely spends 0.085 seconds for a video frame and its average accuracy can achieve about 98%. Hence, the proposed scheme can keep lower computing complexity, however it still can obtain a well accuracy.

This study examined current trends in news topics and text themes of news coverage in the USA and Taiwan about international players from Asia. Content analysis was used to evaluate news coverage for this study. Ninety-five sampling articles were chosen from the database in the USA while 272 articles were chosen from Taiwan. The results indicated that the media in the USA covered more news stories about international sport marketing than did Taiwan. The results of this study show a win-win situation for the teams in the US and a player's native country. Names of stadiums, league, teams, players and players from Asia are frequently covered in the news articles, which increases readers' and fans' knowledge and name recognition of teams.