Drug safety issues in developing countries are complex and sensitive, and health authorities cannot always simply implement decisions from developed countries because the health system, disease patterns, and lists of marketed drugs all differ. A system for proactive and effective surveillance of drugs in each nation is needed to identify and manage the exact drug-related problems faced by patients in these countries. Vietnam launched its university-based National Drug Information and Adverse Drug Reaction Monitoring Centre (NDIADRMC) in 2009, a significant step towards catching up with international trends. Although the center is still in its infancy and has limited resources, it has attained some achievements and largely met the minimum World Health Organization requirements for a functional pharmacovigilance center. The number of reports has increased rapidly, with some important signals generated from the national database leading to regulatory actions at a national level. In addition, this system can help detect drug-quality problems that are less common in developed countries. The success of the quantity and quality of reporting, risk assessment, and communication is still limited compared with more developed systems. A number of opportunities remain to enhance the system, particularly in risk communication and evaluation of the impact of pharmacovigilance, and to apply reporting outcomes to reduce drug-related risks throughout the country. More internal and external support is needed to develop a stronger and more comprehensive pharmacovigilance system.

We study the nature of the smectic–isotropic phase transition using a mobile 6-state Potts model. Each Potts state represents a molecular orientation. We show that with the choice of an appropriate microscopic Hamiltonian describing the interaction between individual molecules modeled by a mobile 6-state Potts spins, we observe the smectic phase dynamically formed when we cool the molecules from the isotropic phase to low temperatures (T). In order to elucidate the order of the transition and the low-T properties, we use the high-performance Wang–Landau flat energy-histogram technique. We show that the smectic phase goes to the liquid (isotropic) phase by melting/evaporating layer by layer starting from the film surface with increasing T. At a higher T, the whole remaining layers become orientationally disordered. The melting of each layer is characterized by a peak of the specific heat. Such a succession of partial transitions cannot be seen by the Metropolis algorithm. The successive layer meltings/evaporations at low T are found to have a first-order character by examining the energy histogram. These results are in agreement with experiments performed on some smectic liquid crystals.

Ultrasonic guided waves propagating in a fluid layer of uniform thickness bonded to an elastic solid half-space is theoretically investigated in this article. Based on the boundary conditions set for the joined configuration, a characteristic dispersion equation is found and new expressions for free guided waves are introduced. Closed-form solutions of guided waves generated by a time-harmonic load are derived by the use of elastodynamics reciprocity theorems. Through calculation examples, it is shown that the obtained computation of the lowest wave mode approaches the result of the Rayleigh wave in the solid half-space as the layer thickness approaches zero. The aim of the present work is to improve the understanding of wave motions in layered half-spaces for potential applications in the area of bone quantitative ultrasound

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