Analytical Parametric Model Used to Study the Influence of Electrostatic Force on Surface Coverage During Electrospinning of Polymer Fibers

Electrospinning (ES) can readily produce polymer fibers with cross-sectional dimensions ranging from tens of nanometers to tens of microns. Qualitative estimates of surface area coverage are rather intuitive. However, quantitative analytical and numerical methods for predicting surface coverage during ES have not been covered in sufficient depth to be applied in the design of novel materials, surfaces, and devices from ES fibers. This article presents a modeling approach to ES surface coverage where an analytical model is derived for use in quantitative prediction of surface coverage of ES fibers. The analytical model is used to predict the diameter of circular deposition areas of constant field strength and constant electrostatic force. Experimental results of polyvinyl alcohol fibers are reported and compared to numerical models to supplement the analytical model derived. The analytical model provides scientists and engineers a method for estimating surface area coverage. Both applied voltage and capillary-to-collection-plate separation are treated as independent variables for the analysis. The electric field produced by the ES process was modeled using COMSOL Multiphysics software to determine a correlation between the applied field strength and the size of the deposition area of the ES fibers. MATLAB scripts were utilized to combine the numerical COMSOL results with derived analytical equations. Experimental results reinforce the parametric trends produced via modeling and lend credibility to the use of modeling techniques for the qualitative prediction of surface area coverage from ES. (Copyright: 2014 American Vacuum Society.

Characterization of Cucurbitacin-Inspired Estrone Analogues as Novel Inhibitors of Human ATP- Binding Cassette Proteins (ABCB1 and ABCC1)

ATP-binding cassette (ABC) transporters are a large class of integral membrane proteins that contribute to key physiological functions in all organisms by utilizing ATP binding and hydrolysis to transport diverse substrates across membrane barriers. P-glycoprotein (P-gp/ ABCB1) and Multidrug Resistance protein 1 (MRP1/ABCC1) are widely reported ABC transporters associated with multidrug resistance in cancer. Multidrug resistance (MDR) mediated by P-gp and MRP1 is responsible for treatment failures of many metastatic cancers as a result of reduced accumulation, bioavailability and diminished potency of anticancer drugs. Currently, known P-gp and MRP1 inhibitors are limited due to toxicity, lack of selectivity and low therapeutic benefit which necessitates the investigation of novel compounds with improved potency and specificity. In this study, we investigated the inhibition potential of newly synthesized cucurbitacin-inspired estrone analogs (CIEAs) on P-gp and MRP1 mediated MDR. Utilizing a high content fluorescence-based transport activity assay initially developed in our lab, a library of 81 CIEAs were screened to identify inhibitors for P-gp and MRP1 proteins. The screening assay identified eight P-gp inhibitors using calcein-AM as a fluorescent reporter. A total of six MRP1 inhibitors were identified using doxorubicin and calcein red orange as fluorescent reporters. The inhibitory effect of the identified compounds on P-gp and MRP1 activity were confirmed using established cell-based functional assays. The identified inhibitors significantly increased the accumulation of P-gp substrate, calcein-AM and MRP1 substrates, doxorubicin and calcein red orange. Interestingly, the identified inhibitors demonstrated selective sensitization of P-gp and MRP1 overexpressing cancer cell lines towards different anticancer drugs. On the other hand, the identified inhibitors did not alter protein levels of both P-gp and MRP1. Furthermore, our in silico and FRET-based spectroscopic studies showed that the inhibitor compounds directly interact with P-gp and MRP1 proteins. Together, our findings demonstrated that CIEAs are promising drug candidates for further development into therapeutic agents against P-gp and MRP1-mediated multidrug resistance in cancer

A COMPARATIVE CLIMATE POLICY STUDY BETWEEN THE FEDERAL STATES OF GERMANY AND CANADA: THE CASE OF THE GERMAN ENERGIEWENDE

Climate change has become one of the most difficult problems that humankind is confronted with in recent times, especially since the problem seems to defy most policies developed to curb it. In a problem-solving context, it is classified as a wicked problem and by far, the most concerning environmental problem humans have had to face. As much as many climate mitigation efforts have failed across the globe, a couple of them have also gained some success. The German Energiewende is one such case. The Energiewende, according to most authors and observers, has been a resounding success, but the problem is that the assertion tends to be based solely on a single state level analysis with the German political and environmental elements as the standards of measurement. No serious comparative study has been done on the policy in terms of the possibility to replicate it in other jurisdictions. In this regard, this paper seeks to investigate if the German Energiewende’s success is limited to Germany alone due to its federal system peculiarities or it can be replicated in other countries like Canada. Canada is selected for this comparative study because though Canada, like Germany, is a federal state, the federal government has done little to ensure a successful national climate policy. Besides, the few attempts made by the federal government to develop and implement a national climate legislation have often attracted opposition from the provincial governments. This study thus will shed light on what Germany did differently, how Germany is politically different from Canada and how that has contributed to the success story of Germany’s Energiewende

Requirement engineering problems impacting the quality of software in Sub-Saharan Africa

Poor software quality has led to tremendous financial losses, necessitating the goal of this study. This study aimed to find out the major cause of poor quality of software and propose solutions to mitigate the problem. Histogram analysis was conducted using data from software development firms’ online applications used to track all defects and issues for each project, which are logged under a unique project ID. The requirement engineering stage was found to produce the most problems that directly or indirectly impact software quality. The capability maturity model integration, prototyping, ISO 9001, Walkthroughs, and Formal Inspections were proposed as solutions that could be used to mitigate the software quality problems that arise from the requirement engineering stage in the software development life cycle

The law applicable to liability arising from the use of selfdriving cars in the wake of the Fourth Industrial Revolution : a global comparative analysis

Abstract: This study explores the liability associated with the use of autonomous vehicles. With the increase in efforts by automobile industries to manufacture driverless cars, the issue of liability occupies the front seat of the discussion. A major benefit of autonomous and connected vehicles is their potential to ameliorate, if not eradicate, avoidable accidents on roads. Currently, it is estimated that 90% of road accidents are caused by human error. The epoch of driverless vehicles, where the narrative will drastically change, is upon us. This means a shift away from human liability to machine liability, since these technologies have in-built algorithms to ensure autonomous decisions by the vehicle. Product liability becomes crucial in the wake of driverless cars. The gradual and ultimate shift of liability from the traditional human driver to the machine ‘driver’ coupled with the cross-border sale of driverless vehicles provide justification for scholarly attention. Accidents may now be attributed to technological error and not human mistake. Conflict of law issues become central in instances where manufacturers and users live in different parts of the world...LL.M. (International Commercial Law

Solar and tray-drying methods and physicochemical properties of sweetpotato starch

Two drying methods were investigated to determine if drying is possible without affecting the quality of starch. The drying methods were solar dryer (53-55 °C) and electrically powered tray dryer (60 °C). The physicochemical properties of starch from five sweetpotato were evaluated after dehydration using the two methods. The results showed that drying methodshad effect on some physicochemical properties of sweetpotato starch. The tray-dried starches had higher moisture, ash, viscosity, and L* values. The swelling power and solubility values for tray-dried starches were significantly different from solar-dried ones, except for the tray-dried “Sauti” starch. Although the water binding capacity and amylase content were higher in solar-dried starches relative to tray-dried starches, statistically therewas no significant difference(

Evaluating a palliative care education programme for domiciliary care workers

Background: Many domiciliary care workers have reported low confidence and isolation when delivering end of life care in patients’ homes. Project Extension for Community Healthcare Outcomes (ECHO) is an initiative that has demonstrated success in increasing confidence and knowledge of end of life care in UK nursing home and community hospice workers, but it has not been evaluated with domiciliary care workers. Aim: To test the acceptability of Project ECHO to domiciliary care workers as a means of increasing their knowledge of, and confidence in, delivering palliative care, and its effectiveness in reducing their isolation by developing a community of practice. Method: A service evaluation, involving one domiciliary care agency delivering care in the community, was conducted from May 2018 to April 2019. The participants were 25 home care workers who were employed by the agency. Participants were invited to attend an event at which gaps in their knowledge were identified, and a curriculum of learning on the Project ECHO programme was developed. The learning involved 12 educational sessions over 12 months, with each session teaching a different component of palliative care. Questionnaires were completed by the participants before and after the educational sessions to assess their effect. In addition, a focus group was conducted with four of the participants. Results: Comparison of the questionnaires completed before and after participating in the education sessions revealed an increase in self-reported knowledge across all 12 topics of the curriculum and an increase in confidence in seven of the 12 topics. However, attendance across the 12 sessions was variable, with no more than nine being attended by any one participant. Conclusion: Palliative care education for domiciliary care staff using ECHO methodology was well received, relevant and accessible, and may have the potential to improve self-assessed knowledge and confidence. However, finding an ideal time for as many staff to attend as possible may be challenging