Early Changes in Exo- and Endocytosis in the EAE Mouse Model of Multiple Sclerosis Correlate with Decreased Synaptic Ribbon Size and Reduced Ribbon-Associated Vesicle Pools in Rod Photoreceptor Synapses

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system that finally leads to demyelination. Demyelinating optic neuritis is a frequent symptom in MS. Recent studies also revealed synapse dysfunctions in MS patients and MS mouse models. We previously reported alterations of photoreceptor ribbon synapses in the experimental auto-immune encephalomyelitis (EAE) mouse model of MS. In the present study, we found that the previously observed decreased imunosignals of photoreceptor ribbons in early EAE resulted from a decrease in synaptic ribbon size, whereas the number/density of ribbons in photoreceptor synapses remained unchanged. Smaller photoreceptor ribbons are associated with fewer docked and ribbon-associated vesicles. At a functional level, depolarization-evoked exocytosis as monitored by optical recording was diminished even as early as on day 7 after EAE induction. Moreover compensatory, post-depolarization endocytosis was decreased. Decreased post-depolarization endocytosis in early EAE correlated with diminished synaptic enrichment of dynamin3. In contrast, basal endocytosis in photoreceptor synapses of resting non-depolarized retinal slices was increased in early EAE. Increased basal endocytosis correlated with increased de-phosphorylation of dynamin1. Thus, multiple endocytic pathways in photoreceptor synapse are differentially affected in early EAE and likely contribute to the observed synapse pathology in early EAE

DEVELOPMENT OF A RESEARCH MODEL TO IMPROVE PERFORMANCE OUTCOMES USING COLLABORATION TECHNOLOGIES

The purpose of this paper is to explore the current research focused upon collaboration technologies and propose a research model. A brief summary of the underlying theories is presented, followed by a discussion of themes and factors which are thought to influence the successful outcomes associated with technology use. A proposed model extends the current research stream on collaboration technologies by examining the constructs of trust, technology quality, and collaboration as a behavior

Music Sharing in China: Theoretical Foundations

In this paper we propose a research model, set of constructs, and instrument for collecting data in China to investigate online behavior in the usage of file sharing technologies by music consumers. As a pilot study to test the constructs in our model and its suitability for use in China, we surveyed 152 people the United States. We found the constructs robust for further investigation. The instrument was revised based upon the results of factor analysis and reliability testing and translated into Chinese. Data was further collected from 439 people in China. Results show that the constructs satisfy the reliability testing as well as structural equation modeling for the Chinese sample

Biogenesis of large dense core vesicles in mouse chromaffin cells

Large dense core vesicle (LDCVs) biogenesis in neuroendocrine cells involves: (a) production of cargo peptides processed in the Golgi; (b) fission of cargo loaded LDCVs undergoing maturation steps; (c) movement of these LDCVs to the plasma membrane. These steps have been resolved over several decades in PC12 cells and in bovine chromaffin cells. More recently, the molecular machinery involved in LDCV biogenesis has been examined using genetically modified mice, generating contradictory results. To address these contradictions, we have used NPY‐mCherry electroporation combined with immunolabeling and super‐resolution structured illumination microscopy. We show that LDCVs separate from an intermediate Golgi compartment, mature in its proximity for about 1 hour and then travel to the plasma membrane. The exocytotic machinery composed of vSNAREs and synaptotagmin1, which originate from either de novo synthesis or recycling, is most likely acquired via fusion with precursor vesicles during maturation. Finally, recycling of LDCV membrane protein is achieved in less than 2 hours. With this comprehensive scheme of LDCV biogenesis we have established a framework for future studies in mouse chromaffin cells

TOWARD AN UNDERSTANDING WHY USERS ENGAGE IN M-COMMERCE

This paper’s aim is to review the existing literature in M-Commerce adoption and propose a research model to examine the necessary factors for users to engage in mobile or M-Commerce. First, the stages of commerce are discussed and defined followed by a review of the Technology Acceptance Model and its application for E-Commerce and M-Commerce. Next is an examination of the antecedents and success factors needed for M-Commerce success. Finally, this paper offers a proposed research model for M-Commerce adoption

Routing Optimizing Decisions in MANET: The Enhanced Hybrid Routing Protocol (EHRP) with Adaptive Routing based on Network Situation

Mobile ad hoc networks (MANETs) are wireless networks that operate without a fixed infrastructure or base station. In MANETs, each node acts as a data source and a router, establishing connections with its neighboring nodes to facilitate communication. This research has introduced the Enhanced Hybrid Routing Protocol (EHRP), which combines the OLSR, AOMDV, and AODV routing protocols while considering the network situation for improved performance. The EHRP protocol begins by broadcasting a RREP (Route Reply) packet to discover a route. The selection of routing options is based on the current network situation. To determine the distance between the source and destination nodes, the proposed EHRP initiates a RREQ (Route Request) packet. In situations where network mobility exceeds the capabilities of the AODV protocol, the EHRP protocol can utilize the OLSR routing protocol for route selection and data transmission, provided that at least 70% of the network nodes remain stable. Additionally, the EHRP protocol effectively handles network load and congestion control through the utilization of the AOMDV routing protocol. Compared to the hybrid routing protocol, the enhanced hybrid routing protocol (EHRP) demonstrates superior performance. Its incorporation of the OLSR, AOMDV, and AODV protocols, along with its adaptive routing adaptation based on network conditions, allows for efficient network management and improved overall network performance. The analysis of packet delivery ratio for EHRP and ZRP reveals that EHRP achieves a packet delivery ratio of 98.01%, while ZRP achieves a packet delivery ratio of 89.99%. These results indicate that the enhanced hybrid routing protocol (EHRP) outperforms the hybrid routing protocol (ZRP) in terms of packet delivery ratio. EHRP demonstrates a higher level of success in delivering packets to their intended destinations compared to ZRP. The analysis of normal routing load for EHRP and ZRP reveals that EHRP exhibits a normal routing load of 0.13%, while ZRP exhibits a higher normal routing load of 0.50%. Based on these results, it can be concluded that the performance of the Enhanced Hybrid Routing Protocol (EHRP) is significantly better than that of the Hybrid Routing Protocol (ZRP) when considering the normal routing load. EHRP demonstrates a lower level of routing overhead and more efficient resource utilization compared to ZRP in scenarios with normal routing load. When comparing the average end-to-end delay between the Enhanced Hybrid Routing Protocol (EHRP) and ZRP, the analysis reveals that EHRP achieves an average delay of 0.06, while ZRP exhibits a higher average delay of 0.23. These findings indicate that the Enhanced Hybrid Routing Protocol (EHRP) performs better than ZRP in terms of average end-to-end delay. EHRP exhibits lower delay, resulting in faster and more efficient transmission of data packets from source to destination compared to ZRP. After considering the overall parameter matrix, which includes factors such as normal routing load, data send and receive throughput, packet delivery ratio, and average end-to-end delay, it becomes evident that the performance of the Enhanced Hybrid Routing Protocol (EHRP) surpasses that of the current hybrid routing protocol (ZRP). Across these metrics, EHRP consistently outperforms ZRP, demonstrating superior performance and efficiency. The Enhanced Hybrid Routing Protocol (EHRP) exhibits better results in terms of normal routing load, higher throughput for data transmission and reception, improved packet delivery ratio, and lower average end-to-end delay. Overall, EHRP offers enhanced performance and effectiveness compared to the existing hybrid routing protocol (ZRP)

A STUDY ON KMS ADOPTION: ATTRIBUTES FOR IMPROVING SYSTEM USER SATISFACTION

The electronic knowledge management system (KMS) adoption phenomenon has long been researched with an objective of exploring and improving how corporations can best manage their knowledge assets and capabilities (Alavi and Leidner, 2001). Corporations invest in the technology and people with an assumption that acceptable returns of improved performance and organizational value will result. By having a more complete perspective on what promotes potential KMS adopters to fully engage in the use, support, and ongoing maintenance of the KMS is beneficial to academics and practitioners. This paper proposes that in order to gain the level of KMS user satisfaction which “fully engages” the end user, a closer examination of the culture characteristics is in order. In addition, this paper will consider the practitioner’s perspective where initial acceptance must be extended into ongoing support and continuous input necessary to keep the KMS useful for the end user community

Organizational Adoption of Web-enabled Services for Information Dissemination

Although communication, collaboration, and transaction processing are some of the important business functions facilitated by the web, timely dissemination of information is critical for ultimate customer satisfaction and potential profitability. The purpose of this study is to determine the affect that contextual factors such as IS maturity, organizational attributes, and environmental characteristics have on perceived usefulness and adoption of web-enabled services for information dissemination in organizations. The key focus of this article is organizational adoption as opposed to individual acceptance for which there have been numerous studies. A research model and eight hypotheses were developed based on past literature. Data were collected from senior managers in small business organizations using an instrument that was carefully developed and tested. Structural equation modeling was performed to test the goodness of fit of the model and the hypotheses. The model suggested adequate fit. The results indicate the importance of perceived usefulness in organizational adoption of web-enabled services for information dissemination. Other important factors for adoption are IS maturity, IS budget and organizational slack