Influence of polymer ratio and surfactants on controlled drug release from cellulosic microsponges

Microsponge refers to a highly cross-linked particle system with a capacity to adsorb (like a dry sponge) pharmaceutical materials. There are various methods available to prepare microsponge formulations, in this study we used quasi emulsion-solvent diffusion method with a combination of hydrophobic (ethyl cellulose) and hydrophilic polymers (hydroxypropyl methylcellulose) mediated via Tween 80 and polyvinyl alcohol. Various ratios and amounts of the polymers and surfactants were used to prepare microsponge formulations using ketoprofen as a model drug and extensively characterised. Our results, for the first time, indicate successful and optimised formulation with desired pharmaceutical characteristics using a combination of hydrophobic and hydrophilic polymers

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Towards hardware-software co-design: a case study of robot arm controller

This paper highlights the notable features of hardware/software co-design, concentrating on the exploration, of the hardware/software design space. The electronic system is specified not only by a set of tasks but also by performances and constraints dependent on the application context. The exploration makes use of metrics for performance analysis. Within this paper, the analysis is illustrated using an example: a real-time robot arm controller. This system is used to control several motors in real-time while avoiding move breaks. The controller makes use of an adaptive speed control in real-time. Several architectural solutions are discussed with regard to their performance and cost. The goal is to select the best solution that satisfies the real-time constraints and minimizes the cost. The solution chosen has been achieved and implemented

A hardware/software codesign case study: design of a robot arm controller

This paper deals with exploration of hardware/software design space. The hardware/software partitioning is illustrated using a real-time robot arm controller. Several architectural solutions are discussed with regard to their performance and cost. The goal is to select the best solution that satisfies the real-time constraints and minimizes the cost

Dust grains potential variation in a Vasyliunas Cairns-distributed plasmas with negative ions

Dust grains' potential variation is presented by using a non-equilibrium complex (dusty) plasma following the Vasyliunas Cairns (VC)-distribution, in which the components such as the electrons, ions [positive and negative], and dust grains have negative charge. For this reason, mathematical statement of currents is solved for dust grains having negatively charge to accomplish the equilibrium state value (viz., q(d) = constant) in the presence of VC-distributed plasmas. Indeed, the current balance equations are modified due to the streaming/nonequilibrium distributed negative ions. Numerically, it is assessed that the important plasma variable, for example, spectral index alpha, spectral index kappa; negative ions streaming velocity (U-0), and negative ions number density (rho), significantly influences the dust grain surface potential (vertical bar psi(d)vertical bar) by: (i) increasing the value of spectral index kappa (kappa) and negative ions density (rho), the magnitude of dust surface potential (vertical bar psi(d)vertical bar) decreases and (ii) increasing the values of spectral index alpha and negative ions streaming velocity (U-0), dust grains surface potential (vertical bar psi(d)vertical bar) increases. The relevance to low-temperature research center in a non-equilibrium dusty (complex) plasma is precisely discussed by associating oxygen ions (negative and positive) species. (c) 2015 AIP Publishing LLC

Hardware-software codesign methodology starting from C/VHDL models

This paper presents a co-synthesis and prototyping environment of mixed hardware/software systems. The approach starts with a high-level C-VHDL specification. This model is refined during the different steps of design to generate an operational prototype which is mapped onto modular and flexible multiprocessor architecture. The combination between the use of existing design tools and the proposed methodology allows to design real-word applications. The environment is used to design a robot arm speed controller. The system uses an algorithm based on fuzzy logic. After some iterations of simulation and synthesis, a prototype is implemented using an architecture composed of software components and hardware components (microprocessor and FPGAs)

An approach for hardware-software codesign

This paper presents a method for modeling and synthesizing mixed HW/SW systems. The proposed method starts from a full system-level specification. Systems are modeled in a synthesis-oriented manner by means of an extended finite state machine model. System-level synthesis is composed of three tasks: partitioning systems into inter-dependent sub-systems, inter-subsystem communication synthesis and architecture mapping onto a flexible architecture platform which includes both hardware and software components. The overall method is illustrated with an example

Dust charging processes with a Cairns-Tsallis distribution function with negative ions

Dust grain charging processes are presented in a non-Maxwellian dusty plasma following the Cairns-Tsallis (q, α)-distribution, whose constituents are the electrons, as well as the positive/negative ions and negatively charged dust grains. For this purpose, we have solved the current balance equation for a negatively charged dust grain to achieve an equilibrium state value (viz., qd = constant) in the presence of Cairns-Tsallis (q, α)-distribution. In fact, the current balance equation becomes modified due to the Boltzmannian/streaming distributed negative ions. It is numerically found that the relevant plasma parameters, such as the spectral indexes q and α, the positive ion-to-electron temperature ratio, and the negative ion streaming speed (U0) significantly affect the dust grain surface potential. It is also shown that in the limit q → 1 the Cairns-Tsallis reduces to the Cairns distribution; for α = 0 the Cairns-Tsallis distribution reduces to pure Tsallis distribution and the latter reduces to Maxwellian distribution for q → 1 and α = 0