The Informational Content Of Changes In Stock Recommendation: Chaebol Vs. Non-Chaebol Affiliated Analysts

Accurate analysts’ reports alleviate information asymmetry between companies and investors by providing accounting information that is useful in investment decision-making for market participants. Investors evaluate the credibility of stock recommendations based on the accuracy of the earnings forecasts of analysts, applying them in the decision-making process. Studies of stock recommendations have focused on their informational content, systematically analyzing the characteristics of recommendations and, to a lesser degree, decision-making factors. For most analysts, when stock recommendations and forecast changes are simultaneously disclosed, a large bias results if analysts fail to consider the magnitude of the market reaction relative to the earnings forecast and stock recommendations. In most previous studies, the informational content of both individual stock recommendations and changes in stock recommendations was investigated. In this study, we examine differences in the informational content depending on the stock recommendations of the report released immediately previous to the current report for the same recommendation. An upgraded (or downgraded) revision within the same recommendation category is associated with a greater (lower) stock price return. Even the same recommendation in the market may cause different reactions depending on both the recommendation itself and on the direction of change of the recommendation. Affiliated analysts have more access to inside information of the companies they analyze. The stock returns after revisions of Chaebol-affiliated analysts are significantly higher than those of non-Chaebol-affiliated analysts

A Literature Review On Chief Executive Officer Hubris And Related Constructs: Is The Theory Of Chief Executive Officer Hubris An Antecedents Or Consequences?

This paper reviews the theory of Chief Executive Officer hubris and related constructs. It is to identify the area of Chief Executive Officer hubris clearly and to clarify the confusion of related constructs which includes: overconfidence, Chief Executive Officer celebrity, and narcissism. We examined the four related constructs comprehensively and evaluated Chief Executive Officer hubris construct as an antecedent or consequence. Throughout the research mainstream, these research related constructs often use the word hubris interchangeably. Many researchers are confused whether Chief Executive Officer hubris is an antecedent or consequence? We will attempt to resolve this issue by examining antecedents and consequences of Chief Executive Officer hubris and related constructs. Furthermore, suggestions and implications for future research based on Chief Executive Officer hubris will be assessed.

Effects of a Dehydroevodiamine-Derivative on Synaptic Destabilization and Memory Impairment in the 5xFAD, Alzheimer's Disease Mouse Model

Carboxy-dehydroevodiamine·HCl (cx-DHED) is a derivative of DHED, which improves memory impairment. Carboxyl modification increases solubility in water, indicating that its bioavailability is higher than that of DHED. Cx-DHED is expected to have better therapeutic effects on Alzheimer's disease (AD) than DHED. In this study, we investigated the therapeutic effects of cx-DHED and the underlying mechanism in 5xFAD mice, transgenic (Tg) mouse model of AD model mice. In several behavioral tests, such as Y-maze, passive avoidance, and Morris water maze test, memory deficits improved significantly in cx-DHED-treated transgenic (Tg) mice compared with vehicle-treated Tg mice. We also found that AD-related pathologies, including amyloid plaque deposition and tau phosphorylation, were reduced after the treatment of Tg mice with cx-DHED. We determined the levels of synaptic proteins, such as GluN1, GluN2A, GluN2B, PSD-95 and Rabphilin3A, and Rab3A in the brains of mice of each group and found that GluN2A and PSD-95 were significantly increased in the brains of cx-DHED-treated Tg mice when compared with the brains of Tg-vehicle mice. These results suggest that cx-DHED has therapeutic effects on 5xFAD, AD model mice through the improvement of synaptic stabilization

Region-specific amyloid-β accumulation in the olfactory system influences olfactory sensory neuronal dysfunction in 5xFAD mice

Background: Hyposmia in Alzheimer’s disease (AD) is a typical early symptom according to numerous previous clinical studies. Although amyloid-β (Aβ), which is one of the toxic factors upregulated early in AD, has been identified in many studies, even in the peripheral areas of the olfactory system, the pathology involving olfactory sensory neurons (OSNs) remains poorly understood. Methods: Here, we focused on peripheral olfactory sensory neurons (OSNs) and delved deeper into the direct relationship between pathophysiological and behavioral results using odorants. We also confirmed histologically the pathological changes in 3-month-old 5xFAD mouse models, which recapitulates AD pathology. We introduced a numeric scale histologically to compare physiological phenomenon and local tissue lesions regardless of the anatomical plane. Results: We observed the odorant group that the 5xFAD mice showed reduced responses to odorants. These also did not physiologically activate OSNs that propagate their axons to the ventral olfactory bulb. Interestingly, the amount of accumulated amyloid-β (Aβ) was high in the OSNs located in the olfactory epithelial ectoturbinate and the ventral olfactory bulb glomeruli. We also observed irreversible damage to the ectoturbinate of the olfactory epithelium by measuring the impaired neuronal turnover ratio from the basal cells to the matured OSNs. Conclusions: Our results showed that partial and asymmetrical accumulation of Aβ coincided with physiologically and structurally damaged areas in the peripheral olfactory system, which evoked hyporeactivity to some odorants. Taken together, partial olfactory dysfunction closely associated with peripheral OSN’s loss could be a leading cause of AD-related hyposmia, a characteristic of early AD. © 2021, The Author(s).1

Design and Development of Nonlinear Optical Microscope System: Simple Implementation with epi-Illumination Platform

During the research using fluorescence-tagged or auto-fluorescence molecules, meaningful information is often buried deep inside the tissue, not its surface. Therefore, especially in the field of biomedical imaging, acquiring optically sectioned images from deep inside the tissue is very important. As well know already, confocal laser scanning microscopy (the most well-known optical sectioning microscopy) gives axially-resolved fluorescence information using the physical background blocking component called pinhole. However, the axial range of imaging is practically limited due to such optical phenomena as the light scattered and absorbed in the tissue. However, nonlinear optical microscopy (e.g. Multiphoton microscopy, harmonic generation microscopy, coherent anti-Stokes Raman spectroscopy) realized by the development of ultrafast light sources has been used for visualizing various tissues, especially in vivo, because of their low sensitivity to the limitation caused by the scattering and the absorption of light. Although nonlinear optical microscopy gives deep tissue image, it is not easy for many researcher to build customized nonlinear system. Here, we introduce an easy and simple way designing and developing such nonlinear optical microscope with upright or inverted epi-illumination platform using commercial optical components only

A Deep Neural Network-Based Pain Classifier Using a Photoplethysmography Signal

Side effects occur when excessive or low doses of analgesics are administered compared to the required amount to mediate the pain induced during surgery. It is important to accurately assess the pain level of the patient during surgery. We proposed a pain classifier based on a deep belief network (DBN) using photoplethysmography (PPG). Our DBN learned about a complex nonlinear relationship between extracted PPG features and pain status based on the numeric rating scale (NRS). A bagging ensemble model was used to improve classification performance. The DBN classifier showed better classification results than multilayer perceptron neural network (MLPNN) and support vector machine (SVM) models. In addition, the classification performance was improved when the selective bagging model was applied compared with the use of each single model classifier. The pain classifier based on DBN using a selective bagging model can be helpful in developing a pain classification system

Design and Development of Nonlinear Optical Microscope System: Simple Implementation with epi-Illumination Platform

During the research using fluorescence-tagged or auto-fluorescence molecules, meaningful information is often buried deep inside the tissue, not its surface. Therefore, especially in the field of biomedical imaging, acquiring optically sectioned images from deep inside the tissue is very important. As well know already, confocal laser scanning microscopy (the most well-known optical sectioning microscopy) gives axially-resolved fluorescence information using the physical background blocking component called pinhole. However, the axial range of imaging is practically limited due to such optical phenomena as the light scattered and absorbed in the tissue. However, nonlinear optical microscopy (e.g. Multiphoton microscopy, harmonic generation microscopy, coherent anti-Stokes Raman spectroscopy) realized by the development of ultrafast light sources has been used for visualizing various tissues, especially in vivo, because of their low sensitivity to the limitation caused by the scattering and the absorption of light. Although nonlinear optical microscopy gives deep tissue image, it is not easy for many researcher to build customized nonlinear system. Here, we introduce an easy and simple way designing and developing such nonlinear optical microscope with upright or inverted epi-illumination platform using commercial optical components only

Thorough economic and carbon footprint analysis of overall hydrogen supply for different hydrogen carriers from overseas production to inland distribution

Environmental problems resulting from fossil-based energy and the depletion of fossil fuels made the alternation of fossil fuels to the environmentally friendly energy resources necessary, and several countries including Korea, Japan, and Germany have recently spotlighted hydrogen as a feasible alternative to fossil fuels. However, the countries heading for the hydrogen economy are usually unable to meet their demands with the inland supply alone due to infrastructure and economic problems caused by expensive resources and a shortage of land. In this kind of background, introducing overseas hydrogen which can be produced economically by utilizing unused resources and land overseas is regarded as an attractive way to meet demands. In this study, an economic as well as a carbon footprint analysis of overall hydrogen supply from overseas to inland for several hydrogen carriers, including liquid hydrogen, liquid organic hydrogen carriers, and ammonia, were conducted. For ship transportation sector, the cross-overs between unit hydrogen costs of liquid organic hydrogen carriers and liquid hydrogen could be found at around 4,000 km and 1 million tons of hydrogen in trends according to distance and amount, respectively. And for distribution sector, pipeline is significantly feasible due to the large amount while trailers show feasibility with hydrogen amount less than around 4,500 tons for delivery sector. A case study of importing hydrogen from Indonesia to Korea was conducted presenting feasibility with all unit hydrogen costs below the 2030 target as stipulated in the Korean roadmap as well as a guideline regarding which sector contributes majorly and should be improved technically and strategically to fulfill the 2040 target in the roadmap. Here, the uncertainty analysis on the overall carbon footprint for the case study was additionally conducted to indicate the future risks of carbon emission from the immature technology

Tunable Stability of All-Inkjet-Printed Double-Gate Carbon Nanotube Thin Film Transistors

In this letter, we improved the stability of all-inkjet-printed carbon nanotube thin film transistors (CNT TFTs) by employing a double gate (DG) structure under an optimal bias condition. In the single-gate structure, the positive threshold voltage (VTH) shift under 10 V positive gate bias stress (PGBS) was significantly reduced with poly(4-vinylphenol) passivation. However, after 100 s, the on-current level was decreased, and a large negative VTH shift was observed. We adopted DG CNT TFTs for a further improvement. When-3V was applied to the top gate, the DG CNT TFTs not only exhibited a much lower VTH shift but also showed a stabilized on-current level. When an appropriate bias is applied to the top gate, charge trapping is induced at the top gate interface and it might balance between the positive and negative shifts. As a result, the overall stress effect is reduced. The p-type only inverter adopting a DG CNT TFT showed improved stability under -3 V of top gate bias. Our experimental result shows that DG structure is a promising candidate for various CNT circuit designs.N

Low Temperature and Cold Stress Significantly Increase Saxitoxins (STXs) and Expression of STX Biosynthesis Genes sxtA4 and sxtG in the Dinoflagellate Alexandrium catenella

Toxic dinoflagellate Alexandrium spp. produce saxitoxins (STXs), whose biosynthesis pathway is affected by temperature. However, the link between the regulation of the relevant genes and STXs’ accumulation and temperature is insufficiently understood. In the present study, we evaluated the effects of temperature on cellular STXs and the expression of two core STX biosynthesis genes (sxtA4 and sxtG) in the toxic dinoflagellate Alexandrium catenella Alex03 isolated from Korean waters. We analyzed the growth rate, toxin profiles, and gene responses in cells exposed to different temperatures, including long-term adaptation (12, 16, and 20 °C) and cold and heat stresses. Temperature significantly affected the growth of A. catenella, with optimal growth (0.49 division/day) at 16 °C and the largest cell size (30.5 µm) at 12 °C. High concentration of STXs eq were detected in cells cultured at 16 °C (86.3 fmol/cell) and exposed to cold stress at 20→12 °C (96.6 fmol/cell) compared to those at 20 °C and exposed to heat stress. Quantitative real-time PCR (qRT-PCR) revealed significant gene expression changes of sxtA4 in cells cultured at 16 °C (1.8-fold) and cold shock at 20→16 °C (9.9-fold). In addition, sxtG was significantly induced in cells exposed to cold shocks (20→16 °C; 19.5-fold) and heat stress (12→20 °C; 25.6-fold). Principal component analysis (PCA) revealed that low temperature (12 and 16 °C) and cold stress were positively related with STXs’ production and gene expression levels. These results suggest that temperature may affect the toxicity and regulation of STX biosynthesis genes in dinoflagellates