Characteristics of dust-collection efficiency and ozone emission by high-voltage electrode shape of electrostatic precipitator for subway tunnel environment

Journal of Mechanical Science and Technology - The air pollution level of particulate matters in subway tunnel environments is severe. The present study conducted experimental measurements and...     

Detection of shellcodes in drive-by attacks using kernel machines

In this paper, we propose a light-weight framework using kernel machines for the detection of shellcodes used in drive-by download attacks. As the shellcodes are passed in webpages as JavaScript strings, we studied the effectiveness of the proposed approach on about 9850 shellcodes and 10000 JavaScript strings collected from the wild. Our analysis shows that the trained SVMs (Support Vector Machines) classified with an accuracy of over 99 %. Our evaluation of the trained SVM models with different proportions of training datasets proved to perform consistently with an average accuracy of 99.51 % and the proposed static approach proved to be effective against detecting even the polymorphic shellcode variants. The performance of our approach was compared to an emulation based approach and observed that our approach performed with slightly better accuracies by consuming about 33 % of the time consumed by the emulation based approach.     

Combined effects of Diospyros lotus leaf and grape stalk extract in high-fat-diet-induced obesity in mice

Food Science and Biotechnology - The aim of this study was to investigate the combined effects of Diospyros lotus leaves extracts (DLE) and Muscat Bailey A grape stalk extracts (MGSE) in obesity...     

Do IT freelancers increase their entrepreneurial behavior and performance by using IT self-efficacy and social capital? Evidence from Bangladesh

This study applies entrepreneurship theory and social capital perspective to IT freelancing to facilitate a better understanding of it. Our model hypothesizes that both IT self-efficacy and social capital obtained through social media interactions contribute to IT freelancers’ entrepreneurial behavior and then this entrepreneurial behavior influences their performance. We collected primary data from one of the leading online freelancing marketplaces, oDesk.com (currently Upwork.com). Our empirical findings confirm the core assertion of our research model. The implications of these findings for research and practice are discussed. Directions for future research are also provided.     

Transverse vibration of a uniform Euler-Bernoulli beam under varying axial force using differential transformation method

This paper presents the application of techniques of differential transformation method (DTM) to analyze the transverse vibration of a uniform Euler-Bernoulli beam under varying axial force. The governing differential equation of the transverse vibration of a uniform Euler-Bernoulli beam under varying axial force is derived and verified. The varying axial force was extended to the more general case which was high polynomial consisted of many terms. The concepts of DTM were briefly introduced. Numerical calculations are carried out and compared with previous published results. The accuracy and the convergence in solving the problem by DTM are discussed.     

A study on the initial crack curving angle of isotropic/orthotropic bimaterial

In this paper, when the initial propagation angle of a branched crack is calculated from the maximum tangential stress criterion (MTSC) and the minimum strain energy density criterion (MSEDC), it is essential that you use stress components in which higher order terms are considered and stress components at the position in a distance 0.005 mm from the crack tip ( =γ . When an interfacial crack propagates along the interface at a constant velocity, the initial propagation angles of the branched crack are similar to the mode mixities (phase angle) and the theoretical values obtained from MTSC and MSEDC. The initial propagation angle of the branched crack depends considerably on the stress intensity factor K{IN2}.     

AFM study for morphological characteristics and biomechanical properties of human cataract anterior lens capsules

The aim of this study was to quantitatively investigate the morphologies (surface roughness) and biomechanical properties (Young's modulus) of human anterior lens capsules (ALCs) for noncataract and cataract groups using atomic force microscopy. Eight human ALCs obtained during phacoemulsification from patients with senile cataracts (72 ± 13 years) were investigated in both the hydrated and dehydrated conditions. The cataract group showed clearly the proliferated lens epithelial cells (LECs) with a monomorphic cell structure, a diameter of 12.54 ± 4.31 μm, and a height of 0.23 ± 0.04 μm, whereas the control group showed no LECs. A substantial amount of false-positive calcification was observed caused by the deposition of remnants of dried salt solution. Cataract group showed significantly higher surface roughness (382.06 nm, p ≤ 0.001) than control group in the anterior side of ALCs, whereas cataract group showed significantly lower surface roughness (353.79 nm, p ≤ 0.001) than control group in their posterior side. Cataract group showed significantly higher Young's modulus (69.52 kPa, p ≤ 0.001) compared to the control group, regardless of the ALC side. Therefore, it is significant that this study provides a new method to examine the nanostructural characteristic and biomechanical property of human ALCs through a nanometer-scale resolution microscopy technique.     

An early recrudescent case of Stanford type A closing aortic dissection

A 81-year-old female was hospitalized with chest discomfort. Findings of CT scan revealed Stanford type A acute aortic dissection, but the dissecting lumen had already closed with thrombus. Aortogram showed no intimal tear, intimal flap or ulcer like projection. Under the diagnosis of "closing aortic dissection", conservative treatment was selected. The dissecting lumen was disappearing gradually, but she had a sudden chest pain on hospital day 4 and CT scan demonstrated an enlarged and enhanced dissecting lumen. She underwent an emergency operation and a hemiarch replacement was performed successfully. Her postoperative course was uneventful and she was discharged from the hospital in good health.     

Two modes of ligand binding in maltose-binding protein of Escherichia coli. Electron paramagnetic resonance study of ligand-induced global conformational changes by site-directed spin labeling

Binding of ligands to the maltose-binding protein (MBP) of Escherichia coli often causes a global conformational change involving the closure of its two lobes. We have introduced a cysteine residue onto each of these lobes by site-directed mutagenesis and modified these residues with spin labels. Using EPR spectroscopy, we examined the changes, caused by the ligand binding, in distance between the two spin labels, hence between the two lobes. The binding of both maltose and maltotetraose induced a considerable closure of the N- and C-terminal lobes of MBP. Little closure occurred upon the binding of maltotetraitol or beta-cyclodextrin. Previous study by fluorescence and UV differential absorbance spectroscopy (Hall, J. A., Gehring, K., and Nikaido, H. (1997) J. Biol. Chem. 272, 17605-17609) showed that maltose and a large portion of maltotetraose bound to MBP via one mode (R mode or "end-on" mode), which is physiologically active and leads to the subsequent transport of the ligands across the cytoplasmic membrane. In contrast, maltotetraitol and beta-cyclodextrin bound to MBP via a different mode (B mode or "middle" mode), which is physiologically inactive. The present work suggests that the B mode is nonproductive because ligands binding in this manner prevent the closure of the two domains of MBP, and, as a result, the resulting ligand-MBP complex is incapable of interacting properly with the inner membrane-associated transporter complex.