1,831 research outputs found
How Social Anxiety and Social Factors Influence and Moderate Social Commerce
Following the fast growth of social networking sites (SNS) such as Facebook, Twitter and LinkedIn in the cyber world recently, social commerce has become an important emerging issue on the Internet. Researchers have studied not only online factors but also offline factors, according to the offline-to-online consumer-behavior model. Hence, this study applied approaches to social anxiety, online social interaction and online social support to comprehend the influences of social commerce intentions. After the research survey collected data from SNS (Facebook) users for one month, the researcher analyzed the data and made several findings. First, social anxiety positively moderates the relationship between online social support and social commerce intention. Second, online social interaction directly and indirectly affects social commerce intention through online social support. Theoretical contributions and managerial implications are also discussed, providing several future research directions and suggestions for scholars and SNS operators, respectively
Comparative study of spectral and morphological properties of blends of P3HT with PCBM and ICBA
[[abstract]]We report a comparative study on spectral and morphological properties of two blend systems for polymer solar cells: the donor material poly(3-hexylthiophene) (P3HT) in combination with the acceptor material of either [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) or indene-C60 bisadduct (ICBA) that was reported to enhance efficiencies of polymer solar cells. Optical microscopy and grazing incidence X-ray scattering reveal the stronger tendency of PCBM to from larger and more ordered domains/grains than ICBA either in pure or blend films. Compared to PCBM, the presence of ICBA also substantially perturbs the organization and longer-range ordering of P3HT in increasing the ICBA ratio in blends. With larger and more ordered phase-separated domains, the P3HT/PCBM blend films exhibit significant optical scattering at higher PCBM ratios. Yet, such optical scattering is not significant for P3HT/ICBA blends (even with high ICBA ratios). Overall, results here suggest the reported higher efficiencies of P3HT/ICBA solar cells (vs. P3HT/PCBM cells) cannot be attributed to larger and/or more ordered phase-separated donor–acceptor domains and other characteristics play more important roles in this case.[[incitationindex]]SCI[[booktype]]電子版[[booktype]]紙
Induction of HSPA4 and HSPA14 by NBS1 overexpression contributes to NBS1-induced in vitro metastatic and transformation activity
<p>Abstract</p> <p>Background</p> <p>Nijmegen breakage syndrome (NBS) is a chromosomal-instability syndrome associated with cancer predisposition, radiosensitivity, microcephaly, and growth retardation. The NBS gene product, NBS1 (p95) or nibrin, is a part of the MRN complex, a central player associated with double-strand break (DSB) repair. We previously demonstrated that NBS1 overexpression contributes to transformation through the activation of PI 3-kinase/Akt. NBS1 overexpression also induces epithelial-mesenchymal transition through the Snail/MMP2 pathway.</p> <p>Methods</p> <p>RT-PCR, Western blot analysis, <it>in vitro </it>migration/invasion, soft agar colony formation, and gelatin zymography assays were performed.</p> <p>Results</p> <p>Here we show that heat shock protein family members, A4 and A14, were induced by NBS1 overexpression. siRNA mediated knockdown of HSPA4 or HSPA14 decreased the <it>in vitro </it>migration, invasion, and transformation activity in H1299 cells overexpressing NBS1. However, HSPA4 or HSPA14 induced activity was not mediated through MMP2. NBS1 overexpression induced the expression of heat shock transcription factor 4b (HSF4b), which correlated with the expression of HSPA4 and HSPA14.</p> <p>Conclusion</p> <p>These results identify a novel pathway (NBS1-HSF4b-HSPA4/HSPA14 axis) to induce migration, invasion, and transformation, suggesting the activation of multiple signaling events induced by NBS1 overexpression.</p
Can Social Exchange Theory Explain Individual Knowledge-Sharing Behavior? A Meta-Analysis
Motivating people to contribute knowledge has become an important research topic and a major challenge for organizations. In order to promote knowledge-sharing, managers need to understand the mechanism that drives individuals to contribute their valuable knowledge. Several theories have been applied to study knowledge-sharing behavior. However, the research settings and findings are often inconsistent. In this study, we use the social exchange theory as our base to develop an extended model that includes IT support and organizational type as moderators. A meta-analysis on 29 reported studies was conducted to examine how different factors in the social exchange theory affect knowledge-sharing behavior. The findings confirm that the social exchange theory plays an important role underlying individuals’ knowledge-sharing behavior. The results also demonstrate that social interaction and trust derived from the social exchange theory and moderated by IT contextual factors can predict individual’s knowledge-sharing behavior
Controlling magnetization reversal in Co/Pt nanostructures with perpendicular anisotropy
We demonstrate a simple method to tailor the magnetization reversal
mechanisms of Co/Pt multilayers by depositing them onto large area nanoporous
anodized alumina (AAO) with various aspect ratios, A = pore depth/diameter.
Magnetization reversal of composite (Co/Pt)/AAO films with large A is governed
by strong domain-wall pinning which gradually transforms into a
rotation-dominated reversal for samples with smaller A, as investigated by a
first-order reversal curve method in conjunction with analysis of the angular
dependent switching fields. The change of the magnetization reversal mode is
attributed to topographical changes induced by the aspect ratio of the AAO
templates.Comment: 12 pages, 3 figure
Disordered Fe vacancies and superconductivity in potassium-intercalated iron selenide (K2-xFe4+ySe5)
The parent compound of an unconventional superconductor must contain unusual
correlated electronic and magnetic properties of its own. In the high-Tc
potassium intercalated FeSe, there has been significant debate regarding what
the exact parent compound is. Our studies unambiguously show that the
Fe-vacancy ordered K2Fe4Se5 is the magnetic, Mott insulating parent compound of
the superconducting state. Non-superconducting K2Fe4Se5 becomes a
superconductor after high temperature annealing, and the overall picture
indicates that superconductivity in K2-xFe4+ySe5 originates from the Fe-vacancy
order to disorder transition. Thus, the long pending question whether magnetic
and superconducting state are competing or cooperating for cuprate
superconductors may also apply to the Fe-chalcogenide superconductors. It is
believed that the iron selenides and related compounds will provide essential
information to understand the origin of superconductivity in the iron-based
superconductors, and possibly to the superconducting cuprates
Palpation of preoperatively inserted indwelling angiocatheter facilitates intraoperative localization of obscure gastrointestinal bleeding of small intestinal origin
SummaryBackgroundPalpation of the indwelling angiographic catheter inserted before operation to localize obscure gastrointestinal bleeding of small intestinal origin during laparotomy has rarely been reported in the literature.PurposeThe purpose of the study is to investigate the role of palpable indwelling angiocatheter inserted before operation in localizing obscure gastrointestinal bleeding of small intestinal origin during laparotomy.MethodsBetween January 2003 and December 2010, seven patients who had a clinical impression of obscure gastrointestinal bleeding of small intestinal origin and angiographic extravasation from the mesenteric artery had an angiocatheter inserted into the distal mesenteric branch. During laparotomy the catheter was palpated to guide subsequent resection of the intestine. The clinical outcomes of these patients were retrospectively reviewed.ResultsDuring laparotomy the retained catheter failed to be palpated in one patient. Six patients underwent segmental resection of intestine under guidance of the palpated catheter. All six patients had positive identification of small bowel bleeding. The yield rate of intraoperative localization was 86% (6 out of 7). Two of the six patients ceased bleeding after operation, but died of underlying disease progression. Four of the six patients had an uneventful postoperative clinical course without recurrent bleeding after a median follow-up period of 25 months.ConclusionPalpation of the indwelling angiographic catheter selectively left before operation is effective for precisely locating obscure gastrointestinal bleeding of small intestinal origin during laparotomy
MUSCLE RECRUITMENT SEQUENCE AND TOTAL REACTION TIME DURING A KARATE ROUNDHOUSE KICK
The purpose of the current study is to quantify the muscle recruitment sequence and total reaction time of fourteen national karate athletes and fourteen college karate athletes while performing upper level roundhouse kick. A 16-channel electromyography was used to measured the muscle activities and an instrumented target was for the evaluation of the response time. The experimental results show that both groups recruited the biceps femoris on the kicking (right) side, followed by the right gastrocnemius, but the subsequent muscle firing sequence was slightly different. This resulted in smaller total reaction time of the national group (736.32 ms) than the time of the control group (770.28 ms) because of different across skill level
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