76 research outputs found

    Impact of Sand Drifts on Jordanian Railway Infrastructures: Alternatives and Mitigation Measures

    Get PDF
    Railways play a critical role in connecting urban and rural regions, thereby promoting the economic sectors of a country. Nevertheless, railway tracks may suffer from several infrastructural problems and deficiencies including sand drifts, particularly in arid and semi-arid regions. This research aims to provide an analytical review of sand-laden drifts and winds, and the measures that can alleviate their impacts on the Aqaba railway tracks, Jordan. It also studies the influence of phosphate deposition as a result of trucksโ€™ passage on the railway tracks. General and practical recommendations from a socio-geographical context are also highlighted in view of proposing tactical solutions and identifying prospects for upcoming research to advance the technical and economical efficiency of the Jordanian railway network. Keywords: Sand drifts, wind, railway network, railway infrastructures, mitigation measures. DOI: 10.7176/CER/14-5-01 Publication date:August 31st 202

    A modern analytic method to solve singular and non-singular linear and non-linear differential equations

    Get PDF
    This article circumvents the Laplace transform to provide an analytical solution in a power series form for singular, non-singular, linear, and non-linear ordinary differential equations. It introduces a new analytical approach, the Laplace residual power series, which provides a powerful tool for obtaining accurate analytical and numerical solutions to these equations. It demonstrates the new approachโ€™s effectiveness, accuracy, and applicability in several ordinary differential equations problem. The proposed technique shows the possibility of finding exact solutions when a pattern to the series solution obtained exists; otherwise, only rough estimates can be given. To ensure the accuracy of the generated results, we use three types of errors: actual, relative, and residual error. We compare our results with exact solutions to the problems discussed. We conclude that the current method is simple, easy, and effective in solving non-linear differential equations, considering that the obtained approximate series solutions are in closed form for the actual results. Finally, we would like to point out that both symbolic and numerical quantities are calculated using Mathematica software

    Empowering Women Between Justice and Equality Between Islamic Law and International Covenants (Reference Study)

    Get PDF
    This study aims to explain the concepts of equality in Islamic Sharia, clarify them, and ensure that women find their full rights within a just law legislated by God Almighty. In the past, women in Western countries suffered from injustice under man-made legislation, which led to demands for their rights resulting in narrow equality between them and men, which was not fair. The study concluded that the term empowerment was closest to the aspect of equality but neglected the role and function of men in society, which is not permitted by Islamic law. Islamic law provides equal rights and duties to both genders, guided by the balance of justice that God Almighty has prescribed. The researchers recommend discussing the concept of empowerment in Islamic law compared to what is stated in international agreements and womens rights organizations through conferences and modern means of communication

    Mucoadhesive microspheres of chitosan and polyvinyl alcohol as a carrier for intranasal delivery of insulin: in vitro and in vivo studies

    Get PDF
    The aim of this study was to investigate the capabilities of chitosan microspheres as drug carrier system in co-formulation with polyvinyl alcohol (PVA), to improve the systemic absorption of intranasal insulin delivery. Insulin loaded microspheres was developed from varying ratio of chitosan solutions along with polyvinyl alcohol (PVA) as additive polymer using spray drying method. Different formulations were developed and morphological studies of the optimized formulas showed that the size range of spherical shaped particulate matters existed from 200 nm to 2 mm. It was clearly observed that physicochemical properties of the microspheres were extensively affected by changing the concentration ratio of the two polymeric materials. In vitro studies of insulin release pattern was performed in various time intervals up to 24 h. It was evident that microspheres made up of chitosan showed initial burst release but slower release as the experiment continued. Microspheres made up of combination of the aforementioned two polymers had instant, sharp and burst drug release. Surprisingly there was no absorption after intranasal delivery of chitosan-PVA microspheres in groups of rats comparing to formulated chitosan microspheres having profound absorption due to their smaller particle size, slower drug release rate and better mucoadhesive properties. Therefore, significant reduction in the plasma blood glucose level for chitosan based optimized formulation was seen right after 4.5 hours compared with control group. The aim of the present study was to fabricate an appropriate application of polymeric microspheres for intranasal delivery of insulin using a novel optimized formulation based on industrial level spray drying technique and to realize the possible barriers in scale up process of its large scale production, considering the effectiveness of polyvinyl alcohol (PVA) and chitosan to increase mucoadhesivness, gelling ability and ultimately effective release behavior pattern of insulin. According to this study, the combination of the polymers used and the mean particle size of formulated microspheres were found to be key factors in insulin drug release resulting for further enhancement of insulin absorption via intranasal route of delivery

    In vitro characterisation of solid drug nanoparticle compositions of efavirenz in a brain endothelium cell line

    Get PDF
    The antiretroviral drug efavirenz displays many desirable pharmacokinetic properties such as a long halfโ€life enabling once daily dosing but suffers from central nervous system safety issues. Various nanotechnologies have been explored to mitigate some of the limitations with efavirenz. While there has been progress in increasing the bioavailability, there has been no attempt to assess the impact of increased exposure to efavirenz on central nervous system safety. The uptake of aqueous and solid drug nanoparticle (SDN) formulations of efavirenz was assessed in the human cerebral microvessel endothelial cells/D3 brain endothelial cell line. The mechanisms of uptake were probed using a panel of transport and endocytosis inhibitors. The cellular accumulation of an efavirenz aqueous solution was significantly reduced by amantadine, but this was not observed with SDNs. The uptake of efavirenz SDNs was reduced by dynasore, but concentrations of the efavirenz aqueous solution were not affected. These data indicate that efavirenz is a substrate for transporters in brain endothelial cells (amantadine is an inhibitor of organic cation transporters 1 and 2), and formation of SDNs may bypass this interaction in favour of a mechanism involving dynaminโ€mediated endocytosis

    Synthetic Geopolymers for Controlled Delivery of Oxycodone: Adjustable and Nanostructured Porosity Enables Tunable and Sustained Drug Release

    Get PDF
    In this article we for the first time present a fully synthetic mesoporous geopolymer drug carrier for controlled release of opioids. Nanoparticulate precursor powders with different Al/Si-ratios were synthesized by a sol-gel route and used in the preparation of different geopolymers, which could be structurally tailored by adjusting the Al/Si-ratio and the curing temperatures. In particular, it was shown that the pore sizes of the geopolymers decreased with increasing Al/Si ratio and that completely mesoporous geopolymers could be produced from precursor particles with the Al/Si ratio 2โˆถ1. The mesoporosity was shown to be associated with a sustained and linear in vitro release profile of the opioid oxycodone. A clinically relevant release period of about 12 h was obtained by adjusting the size of the pellets. The easily fabricated and tunable geopolymers presented in this study constitute a novel approach in the development of controlled release formulations, not only for opioids, but whenever the clinical indication is best treated with a constant supply of drugs and when the mechanical stability of the delivery vehicle is crucial

    Materials for Pharmaceutical Dosage Forms: Molecular Pharmaceutics and Controlled Release Drug Delivery Aspects

    Get PDF
    Controlled release delivery is available for many routes of administration and offers many advantages (as microparticles and nanoparticles) over immediate release delivery. These advantages include reduced dosing frequency, better therapeutic control, fewer side effects, and, consequently, these dosage forms are well accepted by patients. Advances in polymer material science, particle engineering design, manufacture, and nanotechnology have led the way to the introduction of several marketed controlled release products and several more are in pre-clinical and clinical development

    Phase I and Phase II Ocular Metabolic Activities and the Role of Metabolism in Ophthalmic Prodrug and Codrug Design and Delivery

    No full text
    While the mammalian eye is seldom considered an organ of drug metabolism, the capacity for biotransformation is present. Compared to the liver, the metabolic capabilities of the eye are minuscule; however, phase I and phase II metabolic activities have been detected in various ocular structures. The careful consideration of ocular tissue metabolic processes within the eye has important implications for controlling the detoxification of therapeutic agents and for providing the potential for site-specific bio-activation of certain drug molecules, thus enabling significant improvements in drug efficacy and the minimization of side-effect from either local or systemic drug delivery to the eye. Knowledge of these processes is important to prodrug and codrug development and to researchers involved in the design, delivery and metabolism of ophthalmic drugs. This present article reviews the progress in ocular prodrug and codrug design and delivery in light of ocular metabolic activities

    Phase I and Phase II Ocular Metabolic Activities and the Role of Metabolism in Ophthalmic Prodrug and Codrug Design and Delivery

    Get PDF
    Abstract: While the mammalian eye is seldom considered an organ of drug metabolism, the capacity for biotransformation is present. Compared to the liver, the metabolic capabilities of the eye are minuscule; however, phase I and phase II metabolic activities have been detected in various ocular structures. The careful consideration of ocular tissue metabolic processes within the eye has important implications for controlling the detoxification of therapeutic agents and for providing the potential for site-specific bio-activation of certain drug molecules, thus enabling significant improvements in drug efficacy and the minimization of side-effect from either local or systemic drug delivery to the eye. Knowledge of these processes is important to prodrug and codrug development and to researchers involved in the design, delivery and metabolism of ophthalmic drugs. This present article reviews the progress in ocular prodrug and codrug design and delivery in light of ocular metabolic activities
    • โ€ฆ
    corecore