Actually this time is different

Episodes of extraordinary turbulence in global financial markets are examined during eight crises ranging from Asia in 1997-98 to the recent great recession of 2008-10. The analysis focuses on changes in the dependence structures of equity markets through correlation and coskewness to answer the question of whether the great recession is different to other crises in terms of shock transmission through contagion. The results show that ‘this time is different’ and that the great recession is truly a global financial crisis. Other US sourced crises do not affect other markets through contagion, and emerging market crises transmit unexpectedly

EFL university students’ perceptions about cross-cultural presentations via videoconferencing

This study aims to examine EFL university students’ perceptions about cross-cultural videoconferencing presentations for professors in the United States. Nineteen Taiwanese English-as-foreign-language university students who studied in a night program for a bachelor’s degree attended the study. Each of them was free to choose a topic related to Taiwanese cultures and individually made a 25-min presentation plus a five-minute question-and-answer session. After the presentation, they watched recordings of their presentations, completed a five-point Likert-scale attitude survey, and wrote down their reflections. The results showed that the participants were positive about the activity. Based on the analysis of their reflections, the participants acknowledged various aspects of the cross-cultural presentations, such as the opportunities to use English meaningfully, motivation to prepare for the project, and the authentic nature of the interaction. However, the participants had concerns about their language abilities, anxiety, and limited preparation time. Finally, they mentioned the impact the presentation had on them. Pedagogical implications and suggestions for future research are provided

A Research Survey of Electronic Commerce Innovation: Evidence from the Literature

The development of technology has ignited many innovations in business management, especially in the electronic commerce area. The essential example, that is, online stores and online shopping, is a critical evolution and innovation from traditional brick-and-mortar stores to clicks and mortar. Following previous research (Van Oorschot et al.), this present study adopted bibliometric and keyword analysis to review the main characteristics of electronic commerce innovations. Focused on the academic sources, the research data used in this study were searched for and collected from the Web of Science (WoS), a renowned academic database which covers the most influential research journals in electronic commerce. Based on a combination of several keywords related to “innovation” and “electronic commerce,” the keyword search in the WoS was conducted in May 2019. As a result, a total of 334 research articles related to electronic commerce innovations were collected. Derived from the bibliometric analysis, some keywords that were seldom used in the earlier decade (2000-2009), but which rapidly grew in use in the recent decade (2010-2018) were found, including m-commerce, platforms, social commerce, online review, and co-creation. In addition, the top 10 influential articles listed in each of the two decades were identified. The results show some of the research trajectories in EC innovations. In the first decade (2000-2009), the top 10 papers focused on traditional IT adoption, such as self-service technology, enterprise resource planning systems, and the adoption of general attitude-intention theories such as the technology acceptance model. In the recent decade (2010-2018), researchers have shown more diverse interest in innovative EC applications, such as RFID applications, cloud computing, crowdsourcing, etc. Accompanying these EC innovation contexts, in addition to general attitude-intention theories, more theories such as signaling theory, have been adopted

Rapid and sensitive insulated isothermal PCR for point-of-need feline leukaemia virus detection

Objectives: Feline leukaemia virus (FeLV), a gamma retrovirus, causes diseases of the feline haematopoietic system that are invariably fatal. Rapid and accurate testing at the point-of-need (PON) supports prevention of virus spread and management of clinical disease. This study evaluated the performance of an insulated isothermal PCR (iiPCR) that detects proviral DNA, and a reverse transcription (RT)-iiPCR that detects both viral RNA and proviral DNA, for FeLV detection at the PON. Methods: Mycoplasma haemofelis, feline coronavirus, feline herpesvirus, feline calicivirus and feline immunodeficiency virus were used to test analytical specificity. In vitro transcribed RNA, artificial plasmid, FeLV strain American Type Culture Collection VR-719 and a clinical FeLV isolate were used in the analytical sensitivity assays. A retrospective study including 116 clinical plasma and serum samples that had been tested with virus isolation, real-time PCR and ELISA, and a prospective study including 150 clinical plasma and serum samples were implemented to evaluate the clinical performances of the iiPCR-based methods for FeLV detection. Results: Ninety-five percent assay limit of detection was calculated to be 16 RNA and five DNA copies for the RT-iiPCR, and six DNA copies for the iiPCR. Both reactions had analytical sensitivity comparable to a reference real-time PCR (qPCR) and did not detect five non-target feline pathogens. The clinical performance of the RT-iiPCR and iiPCR had 98.82% agreement (kappa[κ] = 0.97) and 100% agreement (κ = 1.0), respectively, with the qPCR (n = 85). The agreement between an automatic nucleic extraction/RT-iiPCR system and virus isolation to detect FeLV in plasma or serum was 95.69% (κ = 0.95) and 98.67% (κ = 0.85) in a retrospective (n = 116) and a prospective (n = 150) study, respectively. Conclusions and relevance: These results suggested that both RT-iiPCR and iiPCR assays can serve as reliable tools for PON FeLV detection

High-Frequency Ultrasound Imaging to Evaluate Liver Fibrosis Progression in Rats and Yi Guan Jian Herbal Therapeutic Effects

The animals used in liver fibrosis studies must usually be sacrificed. Ultrasound has been demonstrated to have the ability to diagnose hepatic fibrosis and cirrhosis in experimental small-animal models. However, few studies have used high-frequency ultrasound (HFU, 40 MHz) to monitor changes in the rat liver and other hollow organs longitudinally. In this study, liver fibrosis was induced by administering dimethylnitrosamine (DMN) in SD rats, aged 8 weeks, for three consecutive days per week for up to 4 weeks. A Chinese herbal medicine Yi Guan Jian (YGJ) was orally administered (1.8 g/kg daily) to DMN-induced liver fibrosis rats for 2 weeks. Compared with the normal control rats, rats treated with DMN for either 2 weeks or 4 weeks had significantly lower body weights, liver indexes and elevation of hydroxyproline, GOT, and GPT contents. YGJ herbal treatment remarkably prevented rats from DMN-induced liver fibrosis. The HFU scoring results among the normal controls, 2-week DMN-treated rats, 4-week DMN-treated rats, and combined 2-week YGJ therapy with 4-week DMN-treated rats also reached statistical significance. Thus, HFU is an accurate tool for the longitudinal analysis of liver fibrosis progression in small-animal models, and the YGJ may be useful in reversing the development of hepatic fibrosis

The Involvement of Neuron-Specific Factors in Dendritic Spinogenesis: Molecular Regulation and Association with Neurological Disorders

Dendritic spines are the location of excitatory synapses in the mammalian nervous system and are neuron-specific subcellular structures essential for neural circuitry and function. Dendritic spine morphology is determined by the F-actin cytoskeleton. Factin remodeling must coordinate with different stages of dendritic spinogenesis, starting from dendritic filopodia formation to the filopodia-spines transition and dendritic spine maturation and maintenance. Hundreds of genes, including F-actin cytoskeleton regulators, membrane proteins, adaptor proteins, and signaling molecules, are known to be involved in regulating synapse formation. Many of these genes are not neuron-specific, but how they specifically control dendritic spine formation in neurons is an intriguing question. Here, we summarize how ubiquitously expressed genes, including syndecan-2, NF1 (encoding neurofibromin protein), VCP, and CASK, and the neuron-specific gene CTTNBP2 coordinate with neurotransmission, transsynaptic signaling, and cytoskeleton rearrangement to control dendritic filopodia formation, filopodia-spines transition, and dendritic spine maturation and maintenance. The aforementioned genes have been associated with neurological disorders, such as autism spectrum disorders (ASDs), mental retardation, learning difficulty, and frontotemporal dementia. We also summarize the corresponding disorders in this report

Influences of source displacement on the features of subwavelength imaging of a photonic crystal slab

In this paper we study the characteristics of subwavelength imaging of a photonic crystal (PhC) superlens under the influence of source displacement. For square- and triangular-lattice photonic crystal lenses, we investigate the influence of changing the lateral position of a single point source on the imaging uniformity and stability. We also study the effect of changing the geometrical center of a pair of sources on the resolution of the double-image. Both properties are found to be sensitive to the displacement, which implies that a PhC slab cannot be treated seriously as a flat lens. We also show that by introducing material absorption into the dielectric cylinders of the PhC slab and widening the lateral width of the slab, the imaging uniformity and stability can be substantially improved. This study helps us to clarify the underlying mechanisms of some recently found phenomena concerning imaging instability.Comment: 6 pages, 4 figures. To appear in J. Phys. Cond. Mat

Triggering Apoptotic Death of Human Malignant Melanoma A375.S2 Cells by Bufalin: Involvement of Caspase Cascade-Dependent and Independent Mitochondrial Signaling Pathways

Bufalin was obtained from the skin and parotid venom glands of toad and has been shown to induce cytotoxic effects in various types of cancer cell lines, but there is no report to show that whether bufalin affects human skin cancer cells. The aim of this investigation was to study the effects of bufalin on human malignant melanoma A375.S2 cells and to elucidate possible mechanisms involved in induction of apoptosis. A375.S2 cells were treated with different concentrations of bufalin for a specific time period and investigated for effects on apoptotic analyses. Our results indicated that cells after exposure to bufalin significantly decreased cell viability, and induced cell morphological changes and chromatin condensation in a concentration-dependent manner. Flow cytometric assays indicated that bufalin promoted ROS productions, loss of mitochondrial membrane potential (ΔΨm), intracellular Ca2+ release, and nitric oxide (NO) formations in A375.S2 cells. Additionally, the apoptotic induction of bufalin on A375.S2 cells resulted from mitochondrial dysfunction-related responses (disruption of the ΔΨm and releases of cytochrome c, AIF, and Endo G), and activations of caspase-3, caspase-8 and caspase-9 expressions. Based on those observations, we suggest that bufalin-triggered apoptosis in A375.S2 cells is correlated with extrinsic- and mitochondria-mediated multiple signal pathways