NANOEMULSION AS A NOVEL OPHTHALMIC DELIVERY SYSTEM FOR ACETAZOLAMIDE

Objective: The aim of this work was to formulate the antiglaucoma drug acetazolamide as ocular nanoemulsion of high therapeutic efficacy and prolonged effect. Methods: Eighteen nanoemulsion formulaions consisting of different oils, surfactants and cosurfactants at various ratios and constant water content (39%) were prepared based on their constructed pseudoternary-phase diagrams. According to the In vitro release studies, three nanoemulsions which exhibited fast drug release were used to prepare acetazolamide nanoemulsions with higher water content (59%). The six nanoemulsions at either water content (39 or 59%) were evaluated for their physicochemical properties and ex- vivo corneal permeability. In addition, Draize rabbit eye irritation test was performed. Moreover, biological evaluation of acetazolamide nanoemulsions for their intraocular pressure lowering activity on glaucomatous albino rabbits was carried out. Results: Isopropyl myristate nanoemulsion prepared with cremophor EL and transcutol P exhibited the fastest drug release among all isopropyl myristate nanoemulsions. Oleic acid nanoemulsion prepared with mixture of tween 80 and cremophor EL as surfactants together with transcutol P showed the fastest drug release among other oleic acid nanoemulsion formulae. Similar results were also observed for peanut oil nanoemulsions. The above mentioned formulations either at 39% or 59% water content showed acceptable physicochemical properties and higher acetazolamide permeability coefficient through goat corneas than that reported for the free drug. They also were non irritant to rabbit eye. Therapeutic efficacy testing revealed that peanut oil nanoemulsion at 39% water content showed better and prolonged intraocular pressure lowering effect relative to either commercial brinzolamide eye drops (Azopt®) or the commercial oral acetazolamide tablet (Cidamex®). Conclusion: Acetazolamide was successfully formulated in nanoemulsion form which revealed high therapeutic efficacy in treatment of glaucoma together with a prolonged effect

Power Rayleigh Distribution for Fitting Total Deaths of Covid-19 in Egypt

The Rayleigh distribution incorporate the lifetime of an object or a service time. In this paper, a new model, called, Power Rayleigh distribution (PR) is submitted for specifying the confirmed total deaths of Corona virus (Covid-19) in Egypt. Statistical and reliability properties of the PR distribution such as survival function, failure rate function, mean residual life, order statistic and extreme value distribution are deduced and studied. Maximum likelihood method is used to evaluate the unknown parameters. Simulation Schemes are introduced. Finally, two sets of real-life data are construed and observed that the new model can provide a best fit to water runoff data and the total deaths of Covid-19 data than other well-known distributions

Pressure Insoles for Gait and Balance Estimation

Stroke leads to impairment in motor ability, gait, and balance, due to brain tissue damage [1]. Clinical therapy following stroke aims at improving mobility and functional capacity. However, there is lack of objective information about subject’s performance once they are transferred home [2]. A wearable, unobtrusive system is needed to describe and compare clinical capacity and performance in a home setting. ForceShoes™ (Xsens Technologies B.V., The Netherlands) had been developed to provide holistic information about subject’s gait and balance measures, such as Extrapolated Centre of Mass (XCoM) and Dynamic Stability Margin (DSM) [3], [4]. Using these measures, a clear distinction between the capacity and performance of the subject is seen. However, this system is obtrusive and requires a long time to set up. This project addresses the need for a wearable and minimal sensing system with an unobtrusive set up. Pressure insoles are lightweight and inconspicuous, and when coupled with an Inertial Measurement Unit (IMU), several gait and balance measures can be estimated. In this study, a 1-D pressure insole system (medilogic ® insoles, T&T medilogic Medizintechnik GmbH, Germany), coupled with IMUs, is investigated for objective quantification of gait and dynamic balance measures. Although, to obtain such measures, 3D forces and moments are required. Linear regression models were used to model 3D forces/moments from the 1D plantar pressures measured from pressure insoles. The predicted forces and moments were used for estimation of XCoM and DSM. These parameters were compared with the estimations done by the forces and moments from the Force Shoes™. The regression model is tested for different walking speeds. High correlation and low differences between the estimations from predicted and measured values show that pressure insoles can indeed be used as an wearable alternative. The results will also be used in designing a wearable in-shoe system that can be used in daily life monitoring for stroke subjects. The study is a part of project 7 of NeuroCIMT, funded by the Dutch National foundation STW. REFERENCES [1] S. F. Tyson, M. Hanley, J. Chillala, A. Selley, and R. C. Tallis, “Balance disability after stroke.,” Phys. Ther., vol. 86, no. 1, pp. 30–38, 2006. [2] B. Klaassen, B.-J. F. van Beijnum, M. Weusthof, D. Hof, F. B. van Meulen, Ed Droog, H. Luinge, L. Slot, A. Tognetti, F. Lorussi, R. Paradiso, J. Held, A. Luft, J. Reenalda, C. Nikamp, J. H. Buurke, H. J. Hermens, and P. H. Veltink, “A Full Body Sensing System for Monitoring Stroke Patients in a Home Environment,” Commun. Comput. Inf. Sci., vol. 511, pp. 378–393, 2016. [3] F. B. van Meulen, D. Weenk, E. H. F. van Asseldonk, H. M. Schepers, P. H. Veltink, and J. H. Buurke, “Analysis of Balance during Functional Walking in Stroke Survivors,” PLoS One, vol. 11, no. 11, p. e0166789, Nov. 2016. [4] F. B. van Meulen, D. Weenk, J. H. Buurke, B.-J. F. van Beijnum, and P. H. Veltink, “Ambulatory assessment of walking balance after stroke using instrumented shoes,” J. Neuroeng. Rehabil., vol. 13, no. 1, p. 48, 2016. [5] A. L. Hof, M. G. J. Gazendam, and W. E. Sinke, “The condition for dynamic stability,” J. Biomech., vol. 38, no. 1, pp. 1–8, 2005

Ambulatory Estimation of XCoM using Pressure Insoles and IMUs

Ambulatory gait assessment using minimal sensors has quite an impact for different applications requiring localised sensing. ForceShoes™ was developed as one such solution. It consists of two IMUs, and two 6DoF force and moment (F&M) sensors on each foot1. Additionally, an ultrasound system was added 2. The complete system, also referred to as Ambulatory Gait and Balance System (AGBS), is used to measure ambulatory kinematics and kinetics of the feet while walking. The AGBS has been validated against standard systems2,3. Using the measured F&M, and position estimations from IMUs, the low and high-frequency information of Center of Mass (CoM) is estimated. This was used to estimate the Extrapolated Center of Mass (XCoM)4. XCoM along with base of support provides information about stability during walking4. The unique advantage of the AGBS is its portability and ambulatory measurement when compared to standard systems. The F&M sensors in the AGBS however, are quite bulky, making it heavier and taller than normal shoes. As an alternative, using 1D pressure sensors was studied. Pressure sensors are thin and easy to slip as insoles in shoes. Therefore, they show potential in making the ambulatory system less bulky

An efficient collocation method for a Caputo two-point boundary value problem

peer-reviewedA two-point boundary value problem is considered on the interval , where the leading term in the differential operator is a Caputo fractional-order derivative of order with . The problem is reformulated as a Volterra integral equation of the second kind in terms of the quantity , where is the solution of the original problem. A collocation method that uses piecewise polynomials of arbitrary order is developed and analysed for this Volterra problem; then by postprocessing an approximate solution of is computed. Error bounds in the maximum norm are proved for and . Numerical results are presented to demonstrate the sharpness of these bounds.ACCEPTEDpeer-reviewe