The power of online opinion leaders in negative e-WOM dissemination

Consumers nowadays are able to exchange information and opinions without physical distance constraint through various online social media channels. These online social media channels facilitate negative electronic word-of-mouth (e-WOM) spread over the world much faster than before. Negative e-WOM communication among consumers can damage a brand and may cause a serious crisis for the company. Thus, companies need to closely monitor negative e-WOM communication in social media, in order to identify the problems, to predict the potential negative impact on the business, and to make a strategic decision on how to respond negative consumer opinions. However, the majority of online discussion communities are self-organised, consumers have much more freedom and control than in company-organised discussion channels to exchange information and opinions. The negative e-WOM communication in these online communities are perceived as being more trustworthy, and more likely to be adopted by a large number of consumers. Although marketers have noticed the impact of negative e-WOM on business, it has been a significant challenge to get control of negative e-WOM dissemination in these communities. Researchers have identified an influential force – online opinion leaders- who reside in these online consumers communities. These opinion leaders are recognized as the most important and influential figures affecting online consumers’ negative e-WOM adoption. Companies might be able to intervene negative e-WOM dissemination by influencing opinion leaders’ behaviour within these communities. However, the online opinion leader emergence and leadership process in these online communities are not well studied. It is not clear what mechanism underlies the influences of opinion leaders on negative e-WOM adoption in these online communities. This study attempts to explore the dynamics of online opinion leadership establishment in negative e-WOM spreading development. Particularly, the research intends to investigate: (1) How does online opinion leadership emerge in an online community following negative WOM? (2) What types of online opinion leadership emerge based on the interactions and consumer sentiments within an online community? (3) How does the role of an online opinion leader evolve over the course of negative e-WOM dissemination? And (4) What are the theoretical and managerial implications for consumer researchers and practitioners in understanding the emergence and evolution of online opinion leadership within a negative e-WOM context? This study has employed a qualitative research method to answer the above research questions. A thematic analysis approach was applied to analyse 1,911 online discussion posts. These posts retrieved from MacRumors online discussion forum are around the issue of the faulty of the new iPhone 6 in September 2014. The activities of opinion leaders and their roles in the online community were analysed in four different discussion phases based on the negative e-WOM development. The main contribution of this research is three-fold. First, the results illustrate a leadership role taking sequence tabulation to portray how online opinion leaders accordingly gain leading position as the discussion volume changes. Second, the finding extends theoretical understanding of the dynamic of opinion leader’s activities and their roles in a negative e-WOM context which has been missing in the past research. More specifically, the findings identified eight important roles for the establishment of opinion leadership in negative e-WOM development. Among these eight roles, the following were identified as crucial in an opinion leader successfully gaining control of the spread of negative e-WOM, and eventually eliminating it: community member, helper, opinion presenter, opinion defender, evidence provider, evidence analyst, reporter and brand guardian. Lastly, it also provides practical suggestions for companies to repair the damage of negative e-WOM in online communities and regain their consumers’ trust by utilizing the power of online opinion leader

Perovskite-WS2 Nanosheet Composite Optical Absorbers on Graphene as High-Performance Phototransistors

High-responsivity phototransistors with a structure of perovskite-WS2 nanosheet composite optical absorber and a reduced graphene oxide (rGO) channel layer is demonstrated via a facile and low-cost solution-processing method. The WS2 nanosheets are dispersed within the perovskite matrix, forming the perovskite-WS2 bulk heterojunction (BHJ). The hybrid phototransistor exhibits excellent figures of merit including high photoresponsivity of 678.8 A/W, high specific detectivity of 4.99 × 1011 Jones, high EQE value of 2.04 × 105% and rapid response to photoswitching. The high photoresponsivity could be attributed to the WS2 nanosheets induced photo-generated electron-hole separation promotion effects due to the selective electron trapping effects in the WS2 nanosheets, together with the high carrier mobility of the rGO channel. This work provides a promising platform for constructing high-responsivity photodetectors

N′2,N′5-Bis[(E)-2-hy­droxy­benzyl­idene]-3,4-dimethyl­thio­phene-2,5-dicarbohydrazide

In the title mol­ecule, C22H20N4O4S, both C=N bonds are in an E conformation. The benzene rings form dihedral angles of 12.10 (13) and 25.17 (12)° with the thio­phene ring. The dihedral angle between the two benzene rings is 17.59 (14)°. There are two intra­molecular O—H⋯N hydrogen bonds. In the crystal, N—H⋯O hydrogen bonds connect mol­ecules into chains along [010]

Branched DNA-based Alu quantitative assay for cell-free plasma DNA levels in patients with sepsis or systemic inflammatory response syndrome

AbstractCell-free circulating DNA (cf-DNA) can be detected by various of laboratory techniques. We described a branched DNA–based Alu assay for measuring cf-DNA in septic patients. Compared to healthy controls and systemic inflammatory response syndrome (SIRS) patients, serum cf-DNA levels were significantly higher in septic patients (1426.54 ± 863.79 vs 692.02 ± 703.06 and 69.66 ± 24.66 ng/mL). The areas under the receiver operating characteristic curve of cf-DNA for normal vs sepsis and SIRS vs sepsis were 0.955 (0.884-1.025), and 0.856 (0.749-0.929), respectively. There was a positive correlation between cf-DNA and interleukin 6 or procalcitonin or Acute Physiology and Chronic Health Evaluation II. The cf-DNA concentration was higher in intensive care unit nonsurviving patients compared to surviving patients (2183.33 ± 615.26 vs 972.46 ± 648.36 ng/mL; P < .05). Branched DNA–based Alu assays are feasible and useful to quantify serum cf-DNA levels. Increased cf-DNA levels in septic patients might complement C-reactive protein and procalcitonin in a multiple marker format. Cell-free circulating DNA might be a new marker in discrimination of sepsis and SIRS