1,948 research outputs found
Impacts of Techno-Dependence in The Mobile Instant Messaging Environment
Mobile Instant Messaging (MIM) services such as LINE, WhatsApp, Facebook Messenger and WeChat have already established a mobile communication environment that extends beyond words and sounds. As MIM provides an effective way to communicate, it can improve workplace efficiency, whether within an organization or among offices spread around the world. Nowadays, MIM has been widely accepted as both a social and work tool. The social interaction overload generated by SNSs contributes to emotional exhaustion. Emotional exhaustion, on the other hand, leads to dissatisfaction and discontinuous usage intentions. In the context of MIMs (since they are relative new apps), users whether are likely to experience emotional exhaustion that is generated by social interaction overload, and therefore discontinue their use of MIMs. In contrast to traditional research on IS continued use in the past which defines dependence as a routine and unconscious usage pattern. MIMs offer a communication method that is faster and easier than phone calls or SMS. It is possible that MIMs bring people closer by allowing their users to understand more of the situational matters related to their friends or family, without being limited by distance. Specifically, social-group functions offered by LINE can encourage users to join certain social groups (for instance, family, colleagues, classmates, or friends). Group members can not only discuss common topics, they can also share their “photo albums,” enabling members to enhance their sense of belonging. At the same time, they have the opportunity to feel a sense of being valued, loved, and needed. Although the mobility and accessibility of mobile devices allow users to instantly contact each other on MIMs and on real-time basis, excessive use of MIMs, or MIM techno-dependence, is likely to generate social-related stress among their users. Therefore, this research attempts to explore the possibility that MIM techno-dependency can have non-detrimental effects, and considers the positive and healthy results from MIM techno-dependency due to an increased sense of belonging.
The questions explored include: do MIMs users develop a positive techno-dependence? Does this positive emotional reaction encourage MIMs users to continue their use of MIMs? Since LINE is a relative newcomer to MIM, there is still a dearth of research needed to explore issues related to using MIM as a research tool. This study considers how LINE combines a diverse range of communication approaches—such as voice, texts, maps, pictures, photos, locations, video, and audio—with a variety of community groups such as friends chat, group chat, dynamic news, and official accounts. It seems worthwhile to study characteristics of LINE’s users in order to further explore the issues related to MIM. Through the hypotheses development and a survey research on 685 LINE users, this study inferred that users make frequent use of LINE in the long-term mainly because of four kinds of techno-dependence: people, fun, information, and work. Such techno-dependence generates positive and negative consequences concurrently. On the one hand, because the user’s dependence on LINE enhances his or her belongingness through friends, colleagues, and family, this positive social and emotional reaction will make users satisfied with LINE, and thus increase continuous usage intention for LINE. On the other hand, the user’s dependence on LINE means that they experience social interaction overload resulting in emotional exhaustion.
Dependence on LINE leads to users experiencing pressure from both social message overload and social demand overload, resulting in social interaction overload. This negative social and emotional reaction will cause a decrease in user satisfaction with LINE, thereby reducing the continuous usage intention of LINE. Based on these findings, we suggest that LINE-related techno-dependence can enable users to increase their sense of positive social belongingness, but can also cause negative social interaction overload. It is concluded that the consequences of techno-dependence are characterized by both positive and negative emotions. Users’ evaluations of LINE are simultaneously affected by positive and negative social and emotional factors
Spermatic Cord Metastasis of Primary Hepatocellular Carcinoma Presenting as an Inguinal Mass: A Case Report
Most spermatic cord masses are benign, and malignant spermatic cord tumors are uncommon. Spermatic cord metastases originating from hepatocellular carcinoma (HCC) have not been previously reported in the English language literature as determined by a PubMed search. We report a male patient who presented with a painful palpable mass in the right inguinal area. The patient was diagnosed with HCC in 2004 and undertook a nonsurgical approach to control the cancer. A radical orchiectomy was performed, and the pathological report showed metastatic HCC in the spermatic cord. The patient received palliative radiation therapy because of a positive surgical margin. No recurrence was noted after 6 months of followup
Mutations in the PKM2 exon-10 region are associated with reduced allostery and increased nuclear translocation.
PKM2 is a key metabolic enzyme central to glucose metabolism and energy expenditure. Multiple stimuli regulate PKM2's activity through allosteric modulation and post-translational modifications. Furthermore, PKM2 can partner with KDM8, an oncogenic demethylase and enter the nucleus to serve as a HIF1α co-activator. Yet, the mechanistic basis of the exon-10 region in allosteric regulation and nuclear translocation remains unclear. Here, we determined the crystal structures and kinetic coupling constants of exon-10 tumor-related mutants (H391Y and R399E), showing altered structural plasticity and reduced allostery. Immunoprecipitation analysis revealed increased interaction with KDM8 for H391Y, R399E, and G415R. We also found a higher degree of HIF1α-mediated transactivation activity, particularly in the presence of KDM8. Furthermore, overexpression of PKM2 mutants significantly elevated cell growth and migration. Together, PKM2 exon-10 mutations lead to structure-allostery alterations and increased nuclear functions mediated by KDM8 in breast cancer cells. Targeting the PKM2-KDM8 complex may provide a potential therapeutic intervention
Ultra-wideband Outdoor Communication Characteristics with and without Traffic
[[abstract]]The BER performance for ultra-wideband (UWB) outdoor communication in LOS and NLOS environments with and without traffic is investigated. We obtain the impulse responses of the UWB outdoor environment by both 2.5D SBR-Image method and inverse Fourier transform techniques. The 2.5D SBR-Image method is first considered for two-dimensional environment simulated without heights of obstacles by ray tubes. Then, heights of the obstacles are taken into consideration between the transmitters and receivers. If the height of ray is lower than that of obstacles, the ray is neglected for the receivers. This effectively reduces the simulating time. By using the impulse response of multipath channels, the BER performance for binary pulse amplitude modulation communications over the radio UWB system is evaluated. We have performed computer simulations in LOS and NLOS environments with and without traffic in dense building areas. Numerical results have shown that the multipath effect caused by moving vehicles in the outdoor LOS and NLOS environments has a great impact on BER performance. Rake receivers are used to improve the outage probability. The relationship between traffic and BER performance is investigated; meanwhile, the characteristics of LOS and NLOS outdoor UWB environments are analyzed. Our investigation results can help improve planning and design of the UWB system.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]電子
Camptothecin-Loaded Liposomes with α-Melanocyte-Stimulating Hormone Enhance Cytotoxicity Toward and Cellular Uptake by Melanomas: An Application of Nanomedicine on Natural Product
ABSTRACTIn this study, we attempted to develop functional liposomes loaded with camptothecin and attached to α-melanocyte-stimulating hormone (α-MSH) to target melanoma cells. The liposomes were mainly composed of phosphatidylcholine, cholesterol, and stearylamine, and were characterized by the vesicle size, zeta potential, camptothecin encapsulation efficiency, and release behavior. Results revealed that α-MSH liposomes possessed an average size of approximately 250nm with a surface charge of 60mV. Camptothecin was successfully entrapped by the targeted liposomes with an encapsulation percentage of nearly 95%. The liposomes provided sustained and controlled camptothecin release. Non-targeted liposomes with the drug exerted superior cytotoxicity against melanomas compared to the free control. Cell viability was reduced from 48% to 32% compared to conventional liposomes. Peptide ligand conjugation further promoted cytotoxicity to 18% viability, which was a 2.7-fold decrease versus the free control. According to the images of fluorescence microscopy, α-MSH liposomes exhibited greater cell endocytosis than did non-targeted liposomes and the free control. α-MSH liposomes were predominantly internalized in the cytoplasm. These findings demonstrate that α-MSH liposomes could enhance the anti-melanoma activity of camptothecin owing to their targeting ability and controlled drug delivery
Using Rare Earth Elements to Constrain Particulate Organic Carbon Flux in the East China Sea
Fluxes of particulate organic carbon (POC) in the East China Sea (ECS) have been reported to decrease from the inner continental shelf towards the outer continental shelf. Recent research has shown that POC fluxes in the ECS may be overestimated due to active sediment resuspension. To better characterize the effect of sediment resuspension on particle fluxes in the ECS, rare earth elements (REEs) and organic carbon (OC) were used in separate two-member mixing models to evaluate trap-collected POC fluxes. The ratio of resuspended particles from sediments to total trap-collected particles in the ECS ranged from 82-94% using the OC mixing model, and 30-80% using the REEs mixing model, respectively. These results suggest that REEs may be better proxies for sediment resuspension than OC in high turbidity marginal seas because REEs do not appear to undergo degradation during particle sinking as compared to organic carbon. Our results suggest that REEs can be used as tracers to provide quantitative estimates of POC fluxes in marginal sea
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