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  • Author: Ngoc Thi Pham x
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Abstract

This article investigates the nonlinear stability of eccentrically stiffened moderately thick plates made of functionally graded materials (FGM) subjected to in-plane compressive, thermo-mechanical loads. The equilibrium and compatibility equations for the moderately thick plates are derived by using the first-order shear deformation theory of plates, taking into account both the geometrical nonlinearity in the von Karman sense and initial geometrical imperfections, temperature-dependent properties with Pasternak type elastic foundations. By applying the Galerkin method and using a stress function, the effects of material and geometrical properties, temperature-dependent material properties, elastic foundations, boundary conditions, and eccentric stiffeners on the buckling and post-buckling loading capacity of the eccentrically stiffened moderately thick FGM plates in thermal environments are analyzed and discussed.

Summary

A statement by ACCA in May 2009 that any corporate governance system should consider factors such as transparency, accountability, fairness and responsibility, raises issues in this field over past few years. There are also a few researches which have been done in the field of international corporate governance standards. This paper chooses a different analytical approach and among its aims is to give some certain systematic conclusions.

First, it separates international standards into groups: ICGN and OECD latest principles covered in group 1 while it uses ACCA principles as reference.

Second, it identified differences between these above set of standards which are and have been used as reference principles for many countries and organizations.

Third, it aims to build a selected comparative set of standards for corporate governance system in accordance to international standards.

Last but not least, this paper illustrates some ideas and policy suggestions.

Abstract

Introduction

African swine fever (ASF) was officially reported in Vietnam in February 2019 and spread across the whole country, affecting all 63 provinces and cities.

Material and Methods

In this study, ASF virus (ASFV) VN/Pig/HaNam/2019 (VN/Pig/HN/19) strain was isolated in primary porcine alveolar macrophage (PAM) cells from a sample originating from an outbreak farm in Vietnam’s Red River Delta region. The isolate was characterised using the haemadsorption (HAD) test, real-time PCR, and sequencing. The activity of antimicrobial feed products was evaluated via a contaminated ASFV feed assay.

Results

Phylogenetic analysis of the viral p72 and EP402R genes placed VN/Pig/HN/19 in genotype II and serogroup 8 and related it closely to Eastern European and Chinese strains. Infectious titres of the virus propagated in primary PAMs were 106 HAD50/ml. Our study reports the activity against ASFV VN/Pig/HN/19 strain of antimicrobial Sal CURB RM E Liquid, F2 Dry and K2 Liquid. Our feed assay findings suggest that the antimicrobial RM E Liquid has a strong effect against ASFV replication. These results suggest that among the Sal CURB products, the antimicrobial RM E Liquid may have the most potential as a mitigant feed additive for ASFV infection. Therefore, further studies on the use of antimicrobial Sal CURB RM E Liquid in vivo are required.

Conclusions

Our study demonstrates the threat of ASFV and emphasises the need to control and eradicate it in Vietnam by multiple measures.

Abstract

This paper is devoted to the study of the following perturbed system of nonlinear functional equations

x ∊Ω=[-b,b], i = 1,…., n; where ε is a small parameter, aijk; bijk are the given real constants, Rijk, Sijk , Xijk : Ω → Ω ,gi → Ω →ℝ , Ψ: Ω x ℝ2→ ℝ are the given continuous functions and ƒi :Ω →ℝ are unknown functions. First, by using the Banach fixed point theorem, we find sufficient conditions for the unique existence and stability of a solution of (E). Next, in the case of Ψ ∊ C2(Ω x ℝ2; ℝ); we investigate the quadratic convergence of (E). Finally, in the case of Ψ ∊ CN(Ω x ℝ2; ℝ) and ε sufficiently small, we establish an asymptotic expansion of the solution of (E) up to order N + 1 in ε. In order to illustrate the results obtained, some examples are also given

Abstract

In this work, we fabricated crumpled graphite oxides (CGOs) from discharged electrodes of waste batteries by the cathodic plasma electrolysis process and applied it for arsenic (As) removal from water solutions. Several factors that affect the removal efficiency of As(III) were investigated, including pH, initial concentrations, and contact time. After 120 min of experiment [10 mg of CGO in 40 ml of 1 mg/l As(III) solution], the removal efficiency reached to as high as 98.6%. From the Langmuir isotherm model, the calculated maximum adsorption capacity (qmax) was found to be 47.39 mg/g. The results from this study showed that CGOs could be an effective adsorbent for As(III) removal from the water environment and acts as a promising adsorbent for other heavy metals from contaminated water.

Abstract

Porous nanosilica (PNS) has been attracting much attention in fabrication of nanocarriers for a drug delivery system (DDS). However, the unmodified PNS-based carriers exhibited a significant initial burst release of drug, which may limit their potential clinical application. In this study, PNS was surface conjugated with cyclodextrin (CD) which was functionalized with adamantylamine-polyethylene glycol (APEG) for 5-fluorouracil (5-FU) delivery, in which case CD was used due to its ability to form a stable inclusion complex with 5-FU and APEG. The conjugated PNS (PNSC@APEG) was successfully prepared with spherical shape and diameter around 50 nm, determined by transmission electron microscopy (TEM). In addition, 5-FU was efficiently trapped in PNSC@APEG particles, which were around 63.4%±3.8% and was slowly released up to 3 days in phosphate buffer saline (PBS). Furthermore, the cell proliferation kit I (MTT) assay data showed that PNSC@APEG was a biocompatible nanocarrier. These results indicated that PNSC@APEG nanoparticles have a great potential as novel carriers for anticancer drug delivery.

Abstract

This paper reports the way for the synthesis of nanoplate VO2 (B) particles with controlled morphology. Nanoplate VO2 (B) particle was synthesized by hydrothermal method. Microstructure of VO2 (B) particles were controlled by hydrothermal temperatures and use of Zn doping into VO2 (B) matrix. The microstructure of the particles was shifted from nanowires to nanoplate morphology by changing of hydrothermal temperatures. The doping of Zn into VO2 nanoparticles resulted in an effective achievement of VO2 (B) phase. In addition, luminescence of VO2 (B) nanoparticle was also controlled by the use Zn doping. These results suggest that the potential application of Zn doped VO2 (B) particles for potential application in optical and energy techniques.