The Determinants of Price in Online Auctions: More Evidence from Quantile Regression

This study explores how seller reputations affect auction prices, and concludes that earlier findings may be biased due to the misspecification of seller reputation. This paper contributes to the literature by offering significant empirical evidence using Taiwanese Internet auction data. Our study reveals that the influence of seller reputations on auction prices is significant, irrespective of the assumptions of linear and non-linear relationships with price. However, failure to consider the non-linear setting of seller reputation would have led us to overestimate the impact of reputations on prices because marginal returns to an incremental increase in reputation declines rapidly for sellers who have more than 15 scores. In addition, using quantile regression, this study finds evidence of considerable differences in their impact on auction prices dependent on the distribution of price levels.Internet auction, reputation, Taiwan, Yahoo! Kimo, quantile regression

The Adaptation and Routinization Processes of A Continuous Auditing System Implementation

How to adopt computer-assisted auditing techniques (CAATTs) quickly and develop a continuous auditing system are the critical issues for the implementation of automated auditing techniques. In this research, we study the technological adaptation process of a case company, which continuously implemented four CAATTs projects in three years. We summarized and analyzed the routinization process of how the case company adapted their computer-aided audit procedures from an experimental action to daily usage. An approach based on organizational routines theories was adopted to study group learning and interactions among project members, and to understand how they integrated automated auditing techniques and mechanisms into the existing manual auditing procedures. The process also reveals the incremental progress of an emerging routine from CAATTs adoption to continuous auditing systems. The research results show that the documentation of CAATTs projects and group learning among different functions contribute to the routinization of automated auditing procedures; the continuous auditing system based on the automated auditing program also contributes to routinely audited tasks. However, the improvisational nature of auditing activities, implicit characteristics within general auditing software, and rigidity of automatic auditing programs cause the resistance of internal auditors on CAATTs use, and also impede the emergence and flexibility of computer-aided auditing procedures

A study on the strategic alignment process with information technology for new ventures: from a dynamic capability perspective

Many prior studies suggest that alignment between business strategy and IT strategy is a dynamic and continuous process, but few of them provide theoretic frameworks for this phenomenon. For new ventures, the alignment process involves with the process of resource reconfiguration to sustain competitive advantages in a velocity environment. Thus, in this paper we applied the dynamic capability perspective to analyze the entrepreneurial processes of a semiconductor company in Taiwan. This study aimed to explore how a new venture developed dynamic through integration and reconfiguration of IT resources to accomplish strategic alignment with their business goals. The results indicate that explicitly intended alignment deeply assists with developing IT capabilities and resources, and achieving implemented alignment. The processes of resource transformation affect development of IT capability within the alignment process. However, intended alignment is restricted by agreement on out-dated business strategy and path dependence, caused by existed resources and insufficient support. Especially, path dependence forcefully limits IT strategy and IT capability both. The mission of IT department in each stage, which is challenged by momentous organization changes, is advocated by accumulative resources and is restrained by rigidity of resource. Effective learning for resource integration and applying additional resource on disruptive transformation could mitigate path dependence effects

IT Governance and Organizational Agility: A Study based on Platform Organizing Logic Perspectives

Managing IS changes is critical for IT governance decisions. Thus, firms should be concerned IT agility in order to respond to uncertain changes in a dynamic environment. In this case study, we analyze the course of IT governance decisions to understand how the case company uses IT to enable organizational agility. Further, we adopt platform organizing logic perspectives to identify factors associated with this issue. These factors are classified as collaboration requirements and cohesion forces. We also identify four key principles used by the case company for making their IT governance decisions to sustain their IT agility: balance between collaboration requirements and cohesion forces, autonomy of IS integration and scalability, simplification of business processes by digitized process capital, and entrepreneurial alertness for absorbing new IT capabilities. These findings illustrate how to apply platform organizing logic to IT governance decisions and also respond to the call for research in reframing the role of IT in shaping organizational agility through digital options

Dynamic region of interest transcoding for multipoint video conferencing

This paper presents a region of interest transcoding scheme for multipoint video conferencing to enhance the visual quality. In a multipoint videoconference, usually there are only one or two active conferees at one time which are the regions of interest to the other conferees involved. We propose a Dynamic Sub-Window Skipping (DSWS) scheme to firstly identify the active participants from the multiple incoming encoded video streams by calculating the motion activity of each sub-window, and secondly reduce the frame-rates of the motion inactive participants by skipping these less-important subwindows. The bits saved by the skipping operation are reallocated to the active sub-windows to enhance the regions of interest. We also propose a low-complexity scheme to compose and trace the unavailable motion vectors with a good accuracy in the dropped inactive sub-windows after performing the DSWS. Simulation results show that the proposed methods not only significantly improve the visual quality on the active subwindows without introducing serious visual quality degradation in the inactive ones, but also reduce the computational complexity and avoid whole-frame skipping. Moreover, the proposed algorithm is fully compatible with the H.263 video coding standard. 1

Patient-oriented simulation based on Monte Carlo algorithm by using MRI data

<p>Abstract</p> <p>Background</p> <p>Although Monte Carlo simulations of light propagation in full segmented three-dimensional MRI based anatomical models of the human head have been reported in many articles. To our knowledge, there is no patient-oriented simulation for individualized calibration with NIRS measurement. Thus, we offer an approach for brain modeling based on image segmentation process with <it>in vivo </it>MRI T1 three-dimensional image to investigate the individualized calibration for NIRS measurement with Monte Carlo simulation.</p> <p>Methods</p> <p>In this study, an individualized brain is modeled based on <it>in vivo </it>MRI 3D image as five layers structure. The behavior of photon migration was studied for this individualized brain detections based on three-dimensional time-resolved Monte Carlo algorithm. During the Monte Carlo iteration, all photon paths were traced with various source-detector separations for characterization of brain structure to provide helpful information for individualized design of NIRS system.</p> <p>Results</p> <p>Our results indicate that the patient-oriented simulation can provide significant characteristics on the optimal choice of source-detector separation within 3.3 cm of individualized design in this case. Significant distortions were observed around the cerebral cortex folding. The spatial sensitivity profile penetrated deeper to the brain in the case of expanded CSF. This finding suggests that the optical method may provide not only functional signal from brain activation but also structural information of brain atrophy with the expanded CSF layer. The proposed modeling method also provides multi-wavelength for NIRS simulation to approach the practical NIRS measurement.</p> <p>Conclusions</p> <p>In this study, the three-dimensional time-resolved brain modeling method approaches the realistic human brain that provides useful information for NIRS systematic design and calibration for individualized case with prior MRI data.</p

Control of Kaposi's Sarcoma-Associated Herpesvirus Reactivation Induced by Multiple Signals

The ability to control cellular functions can bring about many developments in basic biological research and its applications. The presence of multiple signals, internal as well as externally imposed, introduces several challenges for controlling cellular functions. Additionally the lack of clear understanding of the cellular signaling network limits our ability to infer the responses to a number of signals. This work investigates the control of Kaposi's sarcoma-associated herpesvirus reactivation upon treatment with a combination of multiple signals. We utilize mathematical model-based as well as experiment-based approaches to achieve the desired goals of maximizing virus reactivation. The results show that appropriately selected control signals can induce virus lytic gene expression about ten folds higher than a single drug; these results were validated by comparing the results of the two approaches, and experimentally using multiple assays. Additionally, we have quantitatively analyzed potential interactions between the used combinations of drugs. Some of these interactions were consistent with existing literature, and new interactions emerged and warrant further studies. The work presents a general method that can be used to quantitatively and systematically study multi-signal induced responses. It enables optimization of combinations to achieve desired responses. It also allows identifying critical nodes mediating the multi-signal induced responses. The concept and the approach used in this work will be directly applicable to other diseases such as AIDS and cancer

Gingyo-San Enhances Immunity and Potentiates Infectious Bursal Disease Vaccination

The purpose of the present study was to investigate the effects of Gingyo-san (GGS), a traditional Chinese medical formula, on peripheral lymphocyte proliferation and serum antibody titers in chickens vaccinated against the infectious bursal disease (IBD) virus. Treatment groups were fed one of three doses of GGS in their diet (0.5%, 1.0% and 2.0%, w/w), and the IBD vaccine was administered at 1 and 3 weeks of age. At Weeks 8, 12 and 16, changes in serum IBD antibody titers were measured via the micro-method and T cell proliferation. In gene expression experiments, GGS-treated peripheral T lymphocytes were stimulated with concanavalin A (ConA) for 24 h. The mRNA expression of interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-4 (IL-4) and interleukin-12 (IL-12) was determined using a semi-quantitative RT-PCR assay. The results showed that a low dose of GGS could significantly raise the antibody titers. Medium and high doses of GGS enhanced IL-2 and IFN-γ production. GGS altered the expression of IL-4 and IL-12 in T lymphocytes. CD4+ T lymphocyte development was also skewed towards the Th1 phenotype. GGS enhanced cell-mediated immunity and augmented the effects of IBD vaccination in strengthening subsequent anti-viral responses

Genomics and proteomics of immune modulatory effects of a butanol fraction of echinacea purpurea in human dendritic cells

<p>Abstract</p> <p>Background</p> <p><it>Echinacea </it>spp. extracts and the derived phytocompounds have been shown to induce specific immune cell activities and are popularly used as food supplements or nutraceuticals for immuno-modulatory functions. Dendritic cells (DCs), the most potent antigen presenting cells, play an important role in both innate and adaptive immunities. In this study, we investigated the specific and differential gene expression in human immature DCs (iDCs) in response to treatment with a butanol fraction containing defined bioactive phytocompounds extracted from stems and leaves of <it>Echinacea purpurea</it>, that we denoted [BF/S+L/Ep].</p> <p>Results</p> <p>Affymetrix DNA microarray results showed significant up regulation of specific genes for cytokines (IL-8, IL-1β, and IL-18) and chemokines (CXCL 2, CCL 5, and CCL 2) within 4 h after [BF/S+L/Ep] treatment of iDCs. Bioinformatics analysis of genes expressed in [BF/S+L/Ep]-treated DCs revealed a key-signaling network involving a number of immune-modulatory molecules leading to the activation of a downstream molecule, adenylate cyclase 8. Proteomic analysis showed increased expression of antioxidant and cytoskeletal proteins after treatment with [BF/S+L/Ep] and cichoric acid.</p> <p>Conclusion</p> <p>This study provides information on candidate target molecules and molecular signaling mechanisms for future systematic research into the immune-modulatory activities of an important traditional medicinal herb and its derived phytocompounds.</p

Carbon nanotube composites for glucose biosensor incorporated with reverse iontophoresis function for noninvasive glucose monitoring

This study aims to develop an amperometric glucose biosensor, based on carbon nanotubes material for reverse iontophoresis, fabricated by immobilizing a mixture of glucose oxidase (GOD) and multiwalled carbon nanotubes (MWCNT) epoxy-composite, on a planar screen-printed carbon electrode. MWCNT was employed to ensure proper incorporation into the epoxy mixture and faster electron transfer between the GOD and the transducer. Results showed this biosensor possesses a low detection potential (+500 mV), good sensitivity (4 μA/mM) and an excellent linear response range (r2 = 0.999; 0–4 mM) of glucose detection at +500 mV (versus Ag/AgCl). The response time of the biosensor was about 25 s. In addition, the biosensor could be used in conjunction with reverse iontophoresis technique. In an actual evaluation model, an excellent linear relationship (r2 = 0.986) was found between the glucose concentration of the actual model and the biosensor’s current response. Thus, a glucose biosensor based on carbon nanotube composites and incorporated with reverse iontophoresis function was developed