t-shape profile barriers are one of the most successful barriers among many different profiles. it has been shown that using welled diffusers on the top of t-shaped barriers makes a reactive barrier that shows better performance than that of any other used profile barriers compared with their equivalent absorbent barrier. the contribution of the top surface of reactive t-profile barriers to the...

A novel method for the calculation of the free energy difference between two states of a molecular system is presented. The method, an extension of thermodynamic integration, treats the coupling parameter k as a variable in an extended Hamiltonian formulation and propagates it with the physical coordinates. In the resulting generalized ensemble, the crossing of barriers in the physical space is...

Modeling and formulation of full-band quantum transport based on a nonequilibrium tight-binding Green’s function method are presented where realistic band structures, evanescent-mode matching, space charge effect, and scattering effects are taken into account. Our results show that current-voltage characteristics of a GaAs/AlAs double-barrier RTD have larger current densities than the conventio...

Temperature-dependent rf-ion trap mass spectrometry and first-principles simulations reveal the detailed reaction mechanism of the catalytic gas-phase oxidation of CO by free Au(2)(-) ions in the presence of O(2). A metastable intermediate with a mass of Au(2)CO(3)(-) was observed at low temperatures. Two alternative structures corresponding to digold carbonate or peroxyformate are predicted fo...

Antenatal syphilis control is an integral component of reproductive health policies in most countries. In many of these countries, however, the existence of a health policy does not automatically translate into an effective health programme. We argue that neglecting to take into account the perspectives of all stakeholders when planning programmes may be the reason that functional and sustained...

objective(s): irinotecan is a potent anti-cancer drug from camptothecin group which inhibits topoisomerase i. recently, biodegradable and biocompatible polymers such as poly lactide-co-glycolides (plga) have been considered for the preparation of nanoparticles (nps). materials and methods: in this study, irinotecan loaded plga nps were fabricated by an emulsification/solvent diffusion method to...

Controlled and sustained delivery of ophthalmic drugs continues to remain a major focus area in the field of pharmaceutical drug delivery with the emergence of new, more potent drugs and biological response modifiers that may also have very short biological half-lives. The present review was conducted on drug delivery to the ocular route. Polymers with suitable rheological properties can facili...

PROBLEM Reduction of health-care-associated infections in low- and middle-income countries is hampered by inadequate supplies of soap and water and the lack or high cost of alcohol-based handrubs (ABHs). APPROACH In 2005, the World Health Organization (WHO) developed and tested two formulations for ABHs that were suitable for production in health-care facilities. In 2011, the feasibility, adv...

BACKGROUND AND METHODOLOGY Women have used the contraceptive diaphragm for decades. Although use has recently declined, the diaphragm may find a new role in STI/HIV and dual-prevention programmes when microbicides become available. We developed a questionnaire to examine seven provider issues identified as possible barriers to diaphragm use among advanced practice nurses (APNs) specialising in ...

The reduced mortality, improved joint outcomes and enhanced quality of life, which have been witnessed in the developed world for patients with haemophilia, have been an outstanding achievement. Advancements in biotechnology contributed significantly through the development of improved pathogen screening, viral inactivation techniques and the development of recombinant clotting factors. These w...