288 research outputs found

    Simulation analysis of manipulating light propagation through turbid Media

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    We model light propagation through turbid media by employing the pseudospectral time-domain (PSTD) simulation technique. With specific amplitude and phase, light can be manipulated to propagate through turbid media via multiple scattering. By exploiting the flexibility of the PSTD simulation, we analyze factors that contribute to enhancing light penetration. Specific research findings suggest that it is possible to propagate light with specific amplitude/phase. The reported simulation analysis enables quantitative analyses of directing light through turbid media. Please click Additional Files below to see the full abstract

    Neuroprotective Effects of San-Huang-Xie-Xin-Tang in the MPP+/MPTP Models of Parkinson's Disease In Vitro and In Vivo

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    San-Huang-Xie-Xin-Tang (SHXT), composed of Coptidis rhizoma, Scutellariae radix, and Rhei rhizoma, is a traditional Chinese medicine used for complementary and alternative therapy of cardiovascular and neurodegenerative diseases via its anti-inflammatory and antioxidative effects. The aim of this study is to investigate the protective effects of SHXT in the 1–methyl–4–phenylpyridinium (MPP+)/1–methyl–4–phenyl–1,2,3,6–tetrahydropyridine (MPTP) models of Parkinson's disease. Rat primary mesencephalic neurons and mouse Parkinson disease model were used in this study. Oxidative stress was induced by MPP+ in vitro and MPTP in vivo. In MPP+-treated mesencephalic neuron cultures, SHXT significantly increased the numbers of TH-positive neurons. SHXT reduced apoptotic signals (cytochrome and caspase) and apoptotic death. MPP+-induced gp91phox activation and ROS production were attenuated by SHXT. In addition, SHXT increased the levels of GSH and SOD in MPP+-treated neurons. In MPTP animal model, SHXT markedly increased TH-positive neurons in the substantia nigra pars compacta (SNpc) and improved motor activity of mice. In conclusion, the present results reveal the evidence that SHXT possesses beneficial protection against MPTP-induced neurotoxicity in this model of Parkinson's disease via its antioxidative and antiapoptotic effects. SHXT might be a potentially alternative and complementary medicine for neuroprotection

    Effects of epidural compression on stellate neurons and thalamocortical afferent fibers in the rat primary somatosensory cortex

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    A number of neurological disorders such as epidural hematoma can cause compression of cerebral cortex. We here tested the hypothesis that sustained compression of primary somatosensory cortex may affect stellate neurons and thalamocortical afferent (TCA) fibers. A rat model with barrel cortex subjected to bead epidural compression was used. Golgi‑Cox staining analyses showed the shrinkage of dendritic arbors and the stripping of dendritic spines of stellate neurons for at least 3 months post‑lesion. Anterograde tracing analyses exhibited a progressive decline of TCA fiber density in barrel field for 6 months post‑lesion. Due to the abrupt decrease of TCA fiber density at 3 days after compression, we further used electron microscopy to investigate the ultrastructure of TCA fibers at this time. Some TCA fiber terminal profiles with dissolved or darkened mitochondria and fewer synaptic vesicles were distorted and broken. Furthermore, the disruption of mitochondria and myelin sheath was observed in some myelinated TCA fibers. In addition, expressions of oxidative markers 3‑nitrotyrosine and 4‑hydroxynonenal were elevated in barrel field post‑lesion. Treatment of antioxidant ascorbic acid or apocynin was able to reverse the increase of oxidative stress and the decline of TCA fiber density, rather than the shrinkage of dendrites and the stripping of dendritic spines of stellate neurons post‑lesion. Together, these results indicate that sustained epidural compression of primary somatosensory cortex affects the TCA fibers and the dendrites of stellate neurons for a prolonged period. In addition, oxidative stress is responsible for the reduction of TCA fiber density in barrels rather than the shrinkage of dendrites and the stripping of dendritic spines of stellate neurons

    On Scalable Service Function Chaining with O(1) Flowtable Entries

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    The emergence of Network Function Virtualization (NFV) enables flexible and agile service function chaining in a Software Defined Network (SDN). While this virtualization technology efficiently offers customization capability, it however comes with a cost of consuming precious TCAM resources. Due to this, the number of service chains that an SDN can support is limited by the flowtable size of a switch. To break this limitation, this paper presents CRT-Chain, a service chain forwarding protocol that requires only constant flowtable entries, regardless of the number of service chain requests. The core of CRT-Chain is an encoding mechanism that leverages Chinese Remainder Theorem (CRT) to compress the forwarding information into small labels. A switch does not need to insert forwarding rules for every service chain request, but only needs to conduct very simple modular arithmetic to extract the forwarding rules directly from CRT-Chain's labels attached in the header. We further incorporate prime reuse and path segmentation in CRT-Chain to reduce the header size and, hence, save bandwidth consumption. Our evaluation results show that, when a chain consists of no more than 5 functions, CRT-Chain actually generates a header smaller than the legacy 32-bit header defined in IETF. By enabling prime reuse and segmentation, CRT-Chain further reduces the total signaling overhead to a level lower than the conventional scheme, showing that CRT-Chain not only enables scalable flowtable-free chaining but also improves network efficiency

    In vivo sub-femtoliter resolution photoacoustic microscopy with higher frame rates

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    Microscopy based on non-fluorescent absorption dye staining is widely used in various fields of biomedicine for 400 years. Unlike its fluorescent counterpart, non-fluorescent absorption microscopy lacks proper methodologies to realize its in vivo applications with a sub-femtoliter 3D resolution. Regardless of the most advanced high-resolution photoacoustic microscopy, sub-femtoliter spatial resolution is still unattainable, and the imaging speed is relatively slow. In this paper, based on the two-photon photoacoustic mechanism, we demonstrated a in vivo label free laser-scanning photoacoustic imaging modality featuring high frame rates and sub-femtoliter 3D resolution simultaneously, which stands as a perfect solution to 3D high resolution non-fluorescent absorption microscopy. Furthermore, we first demonstrated in vivo label-free two-photon acoustic microscopy on the observation of non-fluorescent melanin distribution within mouse skin

    An Empirical Study of Factors Influencing the Intention to Use SNS App─The Case of Facebook

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    Mobile Internet is coming. The social networking site application (SNS app) has become an important portal for users accessing social networking services. Based on the point of view of existing social network users, this study integrates the technology value-based adoption model and social influence to propose a framework to investigate factors influencing the use intention of the SNS app. A sample of 223 subjects surveyed from Facebook, it was found that user’s perceived value regarding the SNS app positively affects the use intention of the social networking app. Usefulness and Technicality provided by SNS app positively affects perceived value of the app. In addition, user perceived social influence also positively affects the use intention of the social networking app. Results not only advance knowledge related to social network research, as well as provide practical advice to social networking companies. They also suggest how to attract users to continually participate in social networks. Increase activeness and stickiness is critical for social network companies to facilitate long-term development

    Investigating casino event management integration: The case of East and South Asia casinos

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    The aim of this study is to investigate the gap of event management in East and South Asia’s casinos throughout the information provided by casinos on their websites. Main objective is to identify the differences and similarities of event holding in East and South Asia’s casinos and suggest future directions for casino managers and event organizers. Four research questions were developed to provide ourselves a goal, as well as to further our understanding of our investigation. There are two steps to structure our study. First is to evaluate the performance of 138 casino’s websites, which were obtained from worldcasinodirectory. com by using a website evaluation tool that we have constructed. In the second step, we conduct a content analysis for the website so we can identify what kind of events are organized in the area on our samples. The data of the content analysis provides a comparison of events in our sampling, such as the event’s size, type, and frequency of holding an event. We believe that our research would contribute to event organizers and large scale corporations to give them an insight on the overall efficiency of websites, as well as the frequency of events around East and South Asian casinos

    Battery Management System for 24-V Battery-Powered Electric Wheelchair

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    This paper describes a simplified battery-management system using a digital signal processor for a 24-V battery-powered electric wheelchair to modulate and protect the battery from operating outside its safe operating area, such as over-temperature, under-temperature, over-voltage, under-voltage, over-current discharge, or over-current charging. Using the buck-boost circuit topology, we achieved and demonstrated both battery balance and protection in a prototype 12-V/40-Ah series-connected two-battery module. Simulation results show that the proposed battery management system is feasible for a 24-V battery-powered electric wheelchair application

    Investigating casino event management integration: The case of East and South Asia casinos

    Get PDF
    The aim of this study is to investigate the gap of event management in East and South Asia’s casinos throughout the information provided by casinos on their websites. Main objective is to identify the differences and similarities of event holding in East and South Asia’s casinos and suggest future directions for casino managers and event organizers. Four research questions were developed to provide ourselves a goal, as well as to further our understanding of our investigation. There are two steps to structure our study. First is to evaluate the performance of 138 casino’s websites, which were obtained from worldcasinodirectory. com by using a website evaluation tool that we have constructed. In the second step, we conduct a content analysis for the website so we can identify what kind of events are organized in the area on our samples. The data of the content analysis provides a comparison of events in our sampling, such as the event’s size, type, and frequency of holding an event. We believe that our research would contribute to event organizers and large scale corporations to give them an insight on the overall efficiency of websites, as well as the frequency of events around East and South Asian casinos

    Investigating casino event management integration: The case of East and South Asia casinos

    Get PDF
    The aim of this study is to investigate the gap of event management in East and South Asia’s casinos throughout the information provided by casinos on their websites. Main objective is to identify the differences and similarities of event holding in East and South Asia’s casinos and suggest future directions for casino managers and event organizers. Four research questions were developed to provide ourselves a goal, as well as to further our understanding of our investigation. There are two steps to structure our study. First is to evaluate the performance of 138 casino’s websites, which were obtained from worldcasinodirectory. com by using a website evaluation tool that we have constructed. In the second step, we conduct a content analysis for the website so we can identify what kind of events are organized in the area on our samples. The data of the content analysis provides a comparison of events in our sampling, such as the event’s size, type, and frequency of holding an event. We believe that our research would contribute to event organizers and large scale corporations to give them an insight on the overall efficiency of websites, as well as the frequency of events around East and South Asian casinos
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