The Relation between Initial Returns and Audits by the Big Four Accounting Firms

This paper mainly explores the relation between initial returns and audits by the big four accounting firms (the Big Four) in China. The sample period is from January 2007 to December 2012 (the new accounting standards in China is implemented after January 2007 for integrating with the international standards), and selected 1,069 IPO firms listed in the Shanghai Stock Exchange and Shenzhen Stock Exchange in this paper.Many previous studies have proposed the Informational Hypothesis, which states that the initial returns of IPOs being audited by the Big Four are lower than those IPOs being audited by other accounting firms. Oppositely, this paper proposes the Snap-up Hypothesis due to consider the IPOs in mainland China are characterized by “three lows,”: the low reliability of audits being performed by non-Big Four, low proportion of IPOs audits being performed by the Big Four, and low balling ratio. These “three lows” features indicate that the Snap-up Hypothesis applies in the IPOs market of mainland China. In other words, the initial returns of the IPOs being audited by the Big Four are higher than those IPOs being audited by other accounting firms due to the Big Four have the superior reputations.This paper further collects the trading volumes and the turnover ratio on the first day, and selects the Big Four audited IPOs by snap-up tide. As above mentioned, because the snap-up tide and raised stock prices on the first-day listing, investors may purchase the shares when offering and sell them on the first-day listing to obtain considerable profits

Development of titanium dioxide nanoparticles/nanosolution for photocatalytic activity

Biological and chemical contaminants by man-made activities have been serious global issue. Exposure of these contaminants beyond the limits may result in serious environmental and health problem. Therefore, it is important to develop an effective solution that can be easily utilized by mankind. One of the effective ways to overcome this problem is by using titanium dioxide (TiO2). TiO2 is a well-known photocatalyst that widely used for environmental clean-up due to its ability to decompose organic pollutant and kill bacteria. Although it is proven TiO2 has an advantage to solve this concern, its usefulness unfortunately is limited only under UV light irradiation. Therefore, the aim of this work was to investigate the potential of TiO2 that can be activated under visible light by the incorporation of metal ions (Fe, Ag, Zr and Ag-Zr). In this study, sol-gel method was employed for the synthesis of metal ions incorporated TiO2. XRD analysis revealed that all samples content biphasic anatase-brookite TiO2 of size 3 nm to 5 nm. It was found that the incorporation of these metal ions did not change the morphology of TiO2 but the crystallinity and optical properties were affected. The crystallinity of anatase in the biphasic TiO2 was found to be decreased and favored brookite formation. PL analysis showed metal ions incorporation suppressed the recombination of electron-hole pairs while the band gap energy of TiO2 (3.2 eV) was decreased by the incorporation of Fe (2.46 eV) and Ag (2.86 eV). Among this incorporation, Ag-Zr incorporated TiO2 showed highest performance for methyl orange degradation (93%) under fluorescent xxv light irradiation for 10 h. This follows by Zr-TiO2 (82%), Fe-TiO2 (75%) and Ag�TiO2 (43%). Meanwhile, the highest antibacterial performance was exhibited by Ag�TiO2. TEM images showed that E.coli bacterium was killed within 12 h after treated with Ag-TiO2. The results obtained from the fieldwork study established that Ag-Zr incorporation have excellent performances for VOC removal and antibacterial test. The VOC content after treated with Ag-Zr-TiO2 fulfilled the Industry Code of Practice on Indoor Air Quality 2010 which is lower than 3 ppm. In addition, the percentage of microbes also found to be decrease around 45 % within 5 days of monitoring

SnapLink: Fast and Accurate Vision-Based Appliance Control in Large Commercial Buildings

As the number and heterogeneity of appliances in smart buildings increases, identifying and controlling them becomes challenging. Existing methods face various challenges when deployed in large commercial buildings. For example, voice command assistants require users to memorize many control commands. Attaching Bluetooth dongles or QR codes to appliances introduces considerable deployment overhead. In comparison, identifying an appliance by simply pointing a smartphone camera at it and controlling the appliance using a graphical overlay interface is more intuitive. We introduce SnapLink, a responsive and accurate vision-based system for mobile appliance identification and interaction using image localization. Compared to the image retrieval approaches used in previous vision-based appliance control systems, SnapLink exploits 3D models to improve identification accuracy and reduce deployment overhead via quick video captures and a simplified labeling process. We also introduce a feature sub-sampling mechanism to achieve low latency at the scale of a commercial building. To evaluate SnapLink, we collected training videos from 39 rooms to represent the scale of a modern commercial building. It achieves a 94% successful appliance identification rate among 1526 test images of 179 appliances within 120 ms average server processing time. Furthermore, we show that SnapLink is robust to viewing angle and distance differences, illumination changes, as well as daily changes in the environment. We believe the SnapLink use case is not limited to appliance control: it has the potential to enable various new smart building applications.</jats:p

Graphene-based thermionic-thermoradiative solar cells: Concept, efficiency limit, and optimum design

Abstract(#br)Solar energy conversion to electricity usually adopts two main methods: photovoltaic and solar-thermal power generation. Here, graphene-based thermionic-thermoradiative solar cells are expanded to include photovoltaics based on thermionic-thermoradiative converters, hybrid concept, efficiency limit, and optimum design. For realistic and practical design, a comprehensive and consistent model is formulated to include effects of thermal coupling between the absorbers, space-charge effect, non-radiative recombination, and various irreversible energy losses. By combining thermionic emission and thermoradiative mechanisms, thermionic-thermoradiative solar cells make use of electron and photon fluxes simultaneously to efficiently convert solar radiation to electricity, and thus enable a significant improvement in terms of heat utilization and conversion efficiency. Based on the calculated results, optimum choices of materials and the parametric design strategies of the system are determined. The findings predict a high solar-to-electricity efficiency of 0.225 in using a graphene-caesiated tungsten graphene-based thermionic energy converter and an Aluminium-32 gallium-48 arsenide-based thermoradiative cell under 800 sun irradiance. This work also demonstrates the importance of recycling waste heat for performance optimization and opens up new avenues to boost the overall conversion efficiency of such systems

Emerging therapeutic potential of the iridoid molecule, asperuloside: A snapshot of its underlying molecular mechanisms

Over the years, the attention of researchers in the field of modern drug discovery and development has become further intense on the identification of active compounds from plant sources and traditional remedies, as they exhibit higher therapeutic efficacies and improved toxicological profiles. Among the large diversity of plant extracts that have been discovered and explored for their potential therapeutic benefits, asperuloside, an iridoid glycoside, has been proven to provide promising effects as a therapeutic agent for several diseases. Although, this potent substance exists in several genera, it is primarily found in plants belonging to the genus Eucommia. Recent decades have seen a surge in the research on Asperuloside, making it one of the most studied natural products in the field of medicine and pharmacology. In this review, we have attempted to study the various reported mechanisms of asperuloside that form the basis of its wide spectrum of pharmacological activities

Radiograph’s reject rate among Universiti Kebangsaan Malaysia dental undergraduates and its implications

The aim of this study was to evaluate the reject rate of periapical and bitewing radiographs among dental undergraduate students of Universiti Kebangsaan Malaysia (UKM), identify the type of radiographic errors which are frequently encountered and compare reject rates between Year 3, Year 4 and Year 5 dental undergraduates. 118 rejected periapical radiographs and 27 rejected bitewing radiographs were collected from the UKM dental undergraduates’ polyclinics for a duration of 10 months. These rejected radiographs were further evaluated to determine the type of radiographic error. A spiking increase in periapical radiographs reject rate from Year 3 (4%) to Year 4 (11%) was observed. This finding was consistent with the statistically significant difference in the periapical radiographs reject rates for Year 3 and Year 4 (p = 0.0475). In periapical radiographs, the most frequently committed radiographic error was apical cut, followed by high density film. Vice versa, high density film was accounted as the most common radiographic error in bitewing radiography. Analysis of periapical and bitewing radiographs’ reject rates among UKM dental undergraduate entails the necessity to supervise undergraduate students regardless of the year of their undergraduate training in all aspects of the radiographic procedures which include positioning radiographic armamentarium, the setting of radiographic exposure time and the film processing procedure