• Biomedical Science Letters
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• v.17 no.3
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• pp.211-216
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• 2011

The chitosan-coated liposomes (chitosomes) were designed to improve the stability in the gastrointestinal (GI) tract and to enhance the efficacy for oral drug delivery of liposomes. The phosphatic acid (PA)-incorporated anionic liposomes were surface-coated with water soluble chitosan (WSC) by electro-ionic interaction. The shape of the chitosomes observed by transmission electron microscopy (TEM) was spherical in all the formulations and the coating layer by WSC could be founded through TEM images. The mean size and the zeta potential values of the chitosomes increased significantly with depending on the content of WSC added for coating the liposomes. The stability of the chitosomes in the GI tract was confirmed through the change of relative turbidity of the liposomal suspension. The plain liposomes (plasomes) suspension without adding WSC clearly showed the change of relatively turbidity in simulated gastric fluid (SGF), while the change degree of turbidity of the chitosomes in the SGF decreased as increasing of WSC content added for coating liposome. In the 5-CF release study from the plasomes and chitosomes, the plasomes released >90% of the initial 5-CF content at 4 h of release measurement. In contrast, the chitosomes released below 40% of initial content of 5-CF. In conclusion, these results indicate that the chitosomes can be used as a potential carrier for effective oral drug delivery.

• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.25-29
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• 2016

Hepatitis B virus infection can cause hepatic fibrosis leading to cirrhosis and hepatocellular carcinoma. However the mechanism remains poorly understood. In this study, we found that Hepatitis B virus X-protein (HBx) increases vimentin, fibronectin, slug, snail and NOX4 expression. Because NOX4-mediated reactive oxygen species can increase slug and snail, which can induce fibrosis, HBx may be a key regulator of hepatic fibrosis development via NOX4 induction.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.659-672
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• 2020

The outbreak of a recent strain of Coronavirus, known as 'COVID-19', has spread sharply from China across the globe, resulting in a dramatic recession in the global economy. This uncertainty has therefore negatively influenced the business perspective and the various formulated strategies that may not considered such [extreme] circumstances. Using baseline analysis and archival data, this paper reports some of the major implications of COVID-19 on global business and strategy and puts forward suggested research agenda as potential future directions for organizations. In order to survive and remain sustainable, this paper argues that businesses need to revisit their strategies during current COVID-19 crises from three perspectives, including supporting human resources financial commitment, forming cross-functional teams and connecting with their supply chains, as well as investing in corporate social responsibility and doubling down efforts with regard to partnerships. The study also represents a preliminary analysis to the implications of COVID-19 on the business and strategies across the globe and is considered the first such in the field of business, as to date all research papers on COVID-19 have been published in medical-related journals. Directions for future research are also proposed at the end of this study.

• Animal cells and systems
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• v.8 no.2
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• pp.111-115
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• 2004

The epidermis of the mudskipper, Periophthalmus modestus, consists of three layers- the outermost layer, middle layer and stratum germinativum. Extensive fine blood capillaries are present near the superficial layer of epidermis and outermost layer in five fins and a sucking disc. The diffusion distance between the vascular capillaries and the surface of epidermis ranged from 3.6 to 10.9${\mu}$m: 3.6 ${\mu}$m in the sucking disc, 10.9 ${\mu}$m in the anal fin and 4.6 to 5.0 ${\mu}$m in the two dorsal fins. Rate of the surface area of respiratory epithelium, the surface area of the fine blood capillaries occupied per surface area of epidermis in 0.1mm, is 3.7 to 4.4% in two dorsal fins and 1.1% in the anal fin. The middle layer is simpler in structure consisting of small or voluminous cells swollen by epidermal cells, and this layer appeared web-like. Well-developed lymphatic spaces containing lymphocytes existed in the stratum germinativum. The five fins and sucking disc had no epidermal glands.

• International Journal of CAD/CAM
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• v.8 no.1
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• pp.21-28
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• 2009

In the present work, an attempt has been made to construct branching surface from 2-D contours, which are given at different layers and may have branches. If a layer having more than one contour and corresponds to contour at adjacent layers, then it is termed as branching problem and approximated by adding additional points in between the layers. Firstly, the branching problem is converted to single contour case in which there is no branching at any layer and the final branching surface is obtained by skinning. Contours are constructed from the given input points at different layers by energy-based B-Spline approximation. 3-D curves are constructed after adding additional points into the contour points for all the layers having branching problem by using energy-based B-Spline formulation. Final 3-D surface is obtained by skinning 3-D curves and 2-D contours. There are three types of branching problems: (a) One-to-one, (b) One-to-many and (c) Many-to-many. Oneto-one problem has been done by plethora of researchers based on minimizations of twist and curvature and different tiling techniques. One-to-many problem is the one in which at least one plane must have more than one contour and have correspondence with the contour at adjacent layers. Many-to-many problem is stated as m contours at i-th layer and n contours at (i+1)th layer. This problem can be solved by combining one-to-many branching methodology. Branching problem is very important in CAD, medical imaging and geographical information system(GIS).

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.191-195
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• 2004

Drug delivery systems that are based on pectin have been studied for colon specific delivery using the specific activity of colon microflora. The aim of this study was to design a novel method of manufacturing pectin microspheres without oils and surfactants and to investigate the potential use of the pectin microspheres as an oral colon-specific drug carrier. The pectin microspheres were successfully formed using the spray drying method and crosslinking with calcium chloride. From the crosslinked pectin microspheres, indomethacin (IND) release was more suppressed than its release from non-crosslinked microspheres. In a low pH (pH 1.4) environment, the pectin microspheres released IND at an amount of about 18${\pm}$2% of the total loaded weight for 24 h while the release rate of IND was stimulated at neutral pH (pH 7.4). IND release from the pectin microspheres was increased by the addition of pectinase. The results clearly demonstrate that the pectin microspheres that were prepared by the spray drying and crosslinking methods are potential carriers for colon-specific drug deliveries.

• Korean Medical Education Review
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• v.16 no.3
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• pp.132-140
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• 2014

Higher education is under unprecedented pressure for quality improvement and cost containment/reduction due to global competition and ever-increasing tuition costs. These twin challenges require an unconventional approach, and massive open online courses (MOOCs) and flipped learning have recently emerged as two promising educational alternatives not only to address the current problems but also to direct the future of education. This paper discusses the rapidly changing environment for education, MOOCs, and flipped learning as learning alternatives, the relationship between MOOCs and flipped learning, and course redesign for the implementation of flipped learning. The case of Ulsan National Institute of Science and Technology (UNIST) is also discussed for benchmarking purposes since it has been pioneering an innovative educational methodology for teaching and learning IT-enabled active learning methods from its inception in 2009. It has redesigned almost 70 courses (20% of all the courses to offer) for flipped learning. The objectives of UNIST's educational experiment are three-fold: improving the quality of education for students, improving teaching productivity for the faculty, and containing/reducing education costs for the university.

• Nuclear Engineering and Technology
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• v.53 no.9
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• pp.3044-3050
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• 2021

This study offers a Monte Carlo alternative for computing mass energy absorption coefficients of any material through calculation of photon energy deposited per mass of the sample and the energy flux obtained inside a sample volume. This approach is applied in this study to evaluate mass energy absorption coefficients of some amino acids found in human body at twenty-eight different photon energies between 10 keV and 20 MeV. The simulations involved a pencil beam source modeled to emit a parallel beam of mono-energetic photons toward a 1 mean free path thick sample of rectangular parallelepiped geometry. All the components in the problem geometry were surrounded by a 100 cm vacuum sphere to avoid any interactions in materials other than the absorber itself. The results computed using the Monte Carlo radiation transport packages MCNP6.2 and GAMOS5.1 were checked against the theoretical values available from the tables of XMUDAT database. These comparisons indicate very good agreement and support the conclusion that Monte Carlo technique utilized in this fashion may be used as a computational tool for determining the mass energy absorption coefficients of any material whose data are not available in the literature.

• Journal of Preventive Medicine and Public Health
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• v.52 no.4
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• pp.214-223
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• 2019

Objectives: Equity in financial protection against healthcare expenditures is one the primary functions of health systems worldwide. This study aimed to quantify socioeconomic inequality in facing catastrophic healthcare expenditures (CHE) and to identify the main factors contributing to socioeconomic inequality in CHE in Iran. Methods: A total of 37 860 households were drawn from the Households Income and Expenditure Survey, conducted by the Statistical Center of Iran in 2017. The prevalence of CHE was measured using a cut-off of spending at least 40% of the capacity to pay on healthcare services. The concentration curve and concentration index (C) were used to illustrate and measure the extent of socioeconomic inequality in CHE among Iranian households. The C was decomposed to identify the main factors explaining the observed socioeconomic inequality in CHE in Iran. Results: The prevalence of CHE among Iranian households in 2017 was 5.26% (95% confidence interval [CI], 5.04 to 5.49). The value of C was -0.17 (95% CI, -0.19 to -0.13), suggesting that CHE was mainly concentrated among socioeconomically disadvantaged households in Iran. The decomposition analysis highlighted the household wealth index as explaining 71.7% of the concentration of CHE among the poor in Iran. Conclusions: This study revealed that CHE is disproportionately concentrated among poor households in Iran. Health policies to reduce socioeconomic inequality in facing CHE in Iran should focus on socioeconomically disadvantaged households.

• Current Optics and Photonics
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• v.3 no.2
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• pp.150-153
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• 2019

Larynx cancer is a potentially terminal and severe type of neck and head cancer in which malignant cells start to grow and spread upwards in the larynx, or voice box. Smoking tobacco, drinking hot beverages and drinking alcohol are the main risk factors for these tumors. In this study, we aimed to develop a precise, accurate and rapid chemometrics assisted Raman spectroscopy method for diagnosis of larynx cancer in deparaffinized tissue samples. In the proposed method, samples were deparaffinized and 20 microns of each tissue were located on a coverslip. Both healthy (n = 13) and cancerous tissues (n = 13) were exposed to a Raman laser (785 nm) and excitations were recorded between wavenumbers of $50{\sim}1500cm^{-1}$. An Orthogonal Partial Least Square algorithm was applied to evaluate the Raman spectrum obtained. Sensitivity and specificity of the proposed method is high enough with the aid of Principal Component Analysis (PCA) to test the whole model. Healthy and cancerous tissues were accurately and precisely clustered. A rapid, easy and precise diagnosis algorithm was developed for larynx cancer. By this method, some useful data about differences in biomolecules of each group (phospholipids, amides, tyrosine, phenylalanine collagen etc.) was also obtained from the spectra. It is claimed that the optimized method has a great potential for clustering and separating tumor tissues from healthy ones. This novel, rapid, precise and objective diagnosis method may be an alternative for the conventional methods in literature for diagnosis of larynx cancer.