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A new rapid-release SMA-activated micropump with incorporated microneedle arrays and polymeric nanoparticles for optimized transdermal drug delivery
No full textRecent research in Transdermal drug delivery (TDD) systems has predominantly focused on microneedles (MNs) and nanoencapsulated drugs, which offer painless, gradual drug release but may not cater to quick-release drug demands. This study introduces an innovative approach to expedite the TDD process by merging a new rapid-release micropump, MNs, and nanoencapsulation into a modular framework. The fabrication and evaluation of a 3D printed shape memory alloy (SMA)-activated micropump combined with ibuprofen-loaded polymeric nanoparticles delivered via integrated MNs is thereby discussed. The system utilizes an SMA spring wire to actuate a loaded spring which drives an elastic membrane into a chamber integrated with an array of stereolithography (SLA) 3D printed MNs, facilitating painless injection into the dermis layer of the skin. The MNs array is optimized with finite element analysis (FEA) to minimize discomfort from the needles while maximizing the drug load into the skin. The system\u27s performance is characterized through high-speed camera imaging, and an average membrane speed of 0.28 m/s is developed. The system\u27s effectiveness is finally evaluated via a short time frame (5 minutes) ex vivo skin deposition experiment using Franz diffusion cells and rat skin, revealing almost twice the ibuprofen deposition in skin layers with polymeric nanoparticles compared to an untreated solution. The rapid response and demonstrated efficacy of this concept aims to provide a framework for potentially extending this application for transdermal insulin injection
Eco-Friendly KGeCl3 Solar Cells: Performance Enhancement Through HTL Engineering
No full textIn this study, a numerical analysis was performed by utilizing SCAPS to investigate the eco-friendly KGeCl3 perovskite as a promising absorber layer in solar cell devices. The solar cell performance was optimized by considering different suitable hole transport layer (HTL) materials. The absorber layer thickness, doping density, and defect density were investigated. The analysis revealed that V2O5 as an HTL provides the best power conversion efficiency (PCE) among all selected HTLs. The optimal performance was achieved with the solar cell structure ITO/IGZO/KGeCl3/V2O5/Au resulting in a PCE of21.23%, Voc of 0.67 V, Jsc of 42. 04 mA/cm2 and FF of 75.39% at an operating temperature of 300 K
Correction to: MicroRNA-208a: a Good Diagnostic Marker and a Predictor of no-Reflow in STEMI Patients Undergoing Primary Percutaneuos Coronary Intervention (Journal of Cardiovascular Translational Research, (2020), 13, 6, (988-995), 10.1007/s12265-020-10020-9)
No full textAn incorrect affiliation was given for Wael Ali Khalil, Manar Al-Zaky, Nader Talaat Kandil, and Mesbah Taha Hasanein in this article as originally published. The correct affiliation for these authors is: Cardiovascular Medicine Department, Faculty of Medicine, Zagazig University, Zagazig 44519, Egypt. The original article has been corrected
Improving In-Vitro Corrosion and Degradation Performance of Mg–Zn–Ca Alloy for Biomedical Applications by Equal Channel Angular Pressing
No full textMagnesium and its alloys have tremendous potential as biodegradable implant materials but finding the right compromise between corrosion resistance and mechanical properties is an ongoing investigation. This study utilized equal channel angular pressing (ECAP) to fabricate Magnesium-ZX 30 alloy with a refined uniform microstructure. ECAP processing via routes Bc and A for up to four passes resulted in the evolution of dynamically recrystallized textured α-Mg ultrafine grains with a high fraction of low-angle boundaries. 4Bc and 4A processing via ECAP yielded significant grain refinements of 91.6% and 86.5%, respectively compared to the as-annealed condition. X-ray diffraction verified that the α-Mg phase dominated the microstructure as a result of ECAP processing promoting the dissolution of second phases due to the high density of dislocations and vacancies it generated. Electrochemical analysis revealed that ECAP reduced galvanic corrosion and pitting corrosion. Compared to the as-annealed sample, all ECAP-processed conditions displayed a significant decrease in corrosion rates, most notably among them is the 4A condition (97%). Moreover, the surge in grain boundary density and in grain boundary misorientations accelerated the formation of the passivation film, which enhanced the corrosion resistance compared to the as-annealed conditions by 254%, 418% for the 4Bc and 4A processed conditions, respectively. This was corroborated by an immersion test conducted in ringer lactate solution for 360 h. This current work signifies that ECAP processing is capable of producing ZX30 alloy medical implants with high mechanical properties and excellent corrosion resistance that make it suitable for future in-vitro research. Graphical Abstract: (Figure presented.
The Sustainable Development Goals as mechanisms of educational governance in Africa
No full textThis study interrogates how one of the least-studied regional intergovernmental organisations, the African Union (AU), operationalises or recontextualises the global Sustainable Development Goals (SDGs) in the process of developing its post-2015 education and development strategies. Employing critical discourse analysis and drawing on multidisciplinary theories, the author examines the emergence of the SDGs in Africa and the strategies used to make them hegemonic. The analysis indicates that the AU positions itself as an emerging education policy “node†negotiating between global development discourses and African needs and challenges. The strategies that the AU uses highlight potential issues in global governance. On the one hand, the AU positions itself as a victim of the unfair power relationships in global governance, by which international organisations and powerful economies maintain their institutional, structural and productive dominance. This seems to keep the AU “at bay†when it comes to decision-making at the global level. The AU consequently vows to become more critical and assertive, and to forge inclusive and fair relationships with its global partners. On the other hand, post-2015 African development strategies seem to benefit from global norms and make repeated references to scientific knowledge, expert ideas and best practices from the Western world. Overall, then, in order to carry out its role as a continental policy node vis-à -vis global expectations, the AU employs two apparently conflicting strategies: adoption and adaptation. These interpretations of the SDGs add more salience to both consensus and conflict-driven theories of global governance
A Machine Learning Framework for Predicting Fabrication Hours for Industrial Steel Structure Projects
No full textConstruction projects are considered high risk projects especially due to their required large capital making them require extreme attention in estimation as overestimating a project will lead to losing bids and underestimating them will lead to incurring more costs than budgeted resulting in losses. However, estimators are often faced with very tight timelines to finish their estimates leading them to primarily rely on their experience disregarding some crucial factors resulting in inaccurate estimates. In the steel structures industry, the steel fabrication phase accounts for 30 to 40% of the overall project cost; in addition, the steel industry is labor driven; thus, steel structure companies usually estimate their fabrication stage by estimating the required labor hours and multiplying them by crew specific rates; thus, the primary task to enhance the estimates of steel structure fabrication projects is to enhance the duration estimates.
This research is conducted to address the need of a collaborating company to enhance the estimates of their fabrication stage in which most of the losses in the supply only projects in the collaborating company resides. Thus, the objective of this research is to develop a machine learning model to estimate the fabrication hours for industrial steel structures projects; addressing a relatively understudied topic. The research aims to explore the potential utilization of periodical records available in steel fabricator companies to develop machine learning models that can enhance the accuracy of the duration estimates while providing a time efficient tool for estimation engineers to use. The objectives were achieved by employing combinations of six machine learning models and various pre-processing techniques to find the model that best enhances the estimates of the fabrication hours of the collaborating company. This research investigates the use of Ordinary Least Squares Multiple Linear Regression, Lasso Regression, Ridge Regression, K-Nearest Neighbors regression, Support Vector Machines Regression and Multi-layer perception Artificial Neural Networks in tandem with log transformation, polynomial features, Yeo-Johnson transformation, and data splitting in the pursuit of reaching the best model. The research also delves into the identification of the most important features affecting the model performance through sequential feature selection, investigation of linear regression models coefficients and spearman correlation.
The research shows that the most important features are the number of attachments and the weight of plates followed by the weights of light, medium, heavy and extra heavy profiles and the type of steel (main steel, miscellaneous steel, built-up steel). The best modeling technique was the separation of the dataset into three datasets based on the type of steel, applying support vector regression with Yeo-Johnson transformation on the main steel and miscellaneous steel dataset and applying ordinary least squares linear regression on the built-up dataset. The best model has a MAPE of 30% and MAE of 291 hours resulting in a decrease in a 25% decrease in MAPE and a 52% decrease in the MAE compared to using the company’s conventional estimation techniques In addition, the machine learning model resulted in a 94.5% decrease in the percentage error of cost estimates compared to conventional estimation
How Do They See Us?: UNHCR\u27s Representations of Syrian Refugees in “Every Second Counts” Campaign
Get PDFRepresentation is not just an opinion; it is the recreation of realities, facts, and stories that encourage receivers, who are readers and viewers, to build perceptions of a certain topic, objects, events, and human beings. Studying the representation of refugees in the media, UN agencies, and International organizations\u27 press releases, videos, and images has been the main focus for many scholars for decades. However, little is known about refugees\u27 perspectives on visuals produced by UN agencies. This research tries to add to the few studies concerning the captured human object, refugees, perspective using Hall’s encoding/decoding model (Hall, 1997) to analyze representations encoded by UNHCR in the “Every Second Counts” fundraising campaign and decoded by Syrian refugees in Jordan. Therefore, qualitative methods such as in-depth interviews, semi-structured interviews, and discourse analysis were used to understand 1) The representations developed by UNHCR while using Syrian refugees\u27 photos and videos in the campaign via Instagram, alongside the captions used to describe these visual elements, and 2) The perspectives of Syrian refugees living in Jordan and Jordanian professionals working in the humanitarian field about the campaign. This study found that 1) Syrian refugees were mostly represented by UNHCR as victims to motivate the audience to donate as this style enhances the feeling of guilt in the spectator, dependent individuals on UNHCR and the donations that will be paid, and individuals with limited agency and lower status, 2) The study interlocutors adopted different systems/approaches to evaluate how Syrian refugees were represented as Syrian interviewees embedded the victimhood approach because they saw themselves as powerless vulnorbale receivers of aid, while Jordanian professionals embedded the humanitarian savior logic because of their different positionalities, 3) It is crucial for Syrian refugees to be part of the making process of any visual materials to have a sense of autonomy, and 4) The continuous dehumanizing representation of Syrian refugees might increase the gap between refugees and the host community and reinforce stereotypes about refugees
Emotionally Stimulated Activism on TikTok: The Impact of Exposure to Audiovisual Moral Violation on Collective Action in the “Woman, Life, Freedom” Movement
No full textThis thesis unravels new, decentralized mechanisms for mobilization that challenge the traditional understanding of the ‘group-based psychology of collective action.’ By focusing on the Iranian “Woman, Life, Freedom” movement, the study proposes a model that integrates traditional motives for collective action, emotions of different valence, and TikTok audiovisual moral violation stimuli. The proposed model allows for a more complex empirical understanding of the phenomenological experience needed for participation in digital environments. Theoretical assumptions in the current work were guided by the Social Identity Model of Collective Action (SIMCA), the Encapsulated Model of Social Identity for Collective Action (EMSICA), and the theory of Social Identity.
The research uses a between-participants, posttest-only online experiment on a sample of (N=700) individuals conducted during Spring 2024. Results from a parallel mediation analysis revealed that affective injustice, participative efficacy, and politicized identification were all directly and strongly predicted by exposure to moral violation stimuli. The three motives directly and indirectly predicted collective action participation. Further, four mediation analyses revealed that collective action was predicted via a serial mediation between participative efficacy and emotions of hope, affective injustice and politicized identification, affective injustice and participative efficacy, but not via affective injustice and moral outrage. Results from the study generally support theoretical claims about the mobilizing effect of moral violation stimuli during online social movements on TikTok, whereby individuals who encounter harm-based norms are willing to participate in collective action in defense of their moral principles. The study concludes the potential of TikTok as a very promising space in grassroots identity formation and for focusing efforts toward achieving justice.
Keywords: Moral Violation, Emotions, Social Movements, Collective Action, Feminism, TikTok, Audiovisuals, Social Medi
Economic Feasibility of Material Waste Management “Reduction, Reuse, Recycle and Repair’ Strategies in Egypt’s Footwear Industry
Get PDFThe study aims to provide a comprehensive examination of the feasibility of waste management strategies in the leather and footwear industry, both globally and within the specific context of Egypt. It explores the benefits and challenges associated with efficiently recycling, treating, or reusing material waste generated by the footwear industry, with a particular focus on Egypt. The study begins by discussing established waste management practices in the global fashion industry and focusing on footwear material waste.
The study examines successful waste management methods and systems employed globally, highlighting their potential applicability to the Egyptian fashion sector. A key aspect of the study involves an in-depth analysis of the current state of waste generation within Egypt\u27s footwear industry and the existing waste management practices. By quantifying the volume of waste generated and examining how waste is presently handled, the study seeks to determine the potential environmental and economic impacts of introducing new waste management methods.
The primary objective of this exploratory study is to understand the behavior of the factory managers to determine their willingness to do the change and analyze waste management practices to recommend strategies for optimizing implementation. Another important aim is to propose a robust and integrated system for material waste management that involves collaboration between multi stakeholders. This proposed system includes the collection of waste from manufacturing facilities and the subsequent categorization of materials and waste made by intermediaries specialized in waste collection. Specialized recycling companies would then apply their expertise to either recycle, reuse, or treat the waste effectively. Furthermore, the study emphasizes the importance of designing a framework of material waste management practices in the footwear industries which not only addresses environmental concerns but also incorporates monetization strategies or incentives to promote a unified process to manage material waste from the footwear industries in Egypt. This approach aims to create a financial incentive for stakeholders to actively participate in the waste management process. Ultimately, the main goal is to develop a 360-degree framework of sustainable practices for waste management tailored to the unique characteristics of the footwear industry in Egypt. This framework would encompass waste reduction, efficient recycling, economic benefits, and environmental preservation. By achieving this goal, the footwear industry in Egypt can move toward a more sustainable and environmentally responsible future while also fostering economic growth and collaboration among stakeholders
A Policy Perspective to Farmers\u27 Adaptation to Water Scarcity: The Case of Kafr El Sheikh, Egypt
Get PDFThis study deals with Egypt’s growing challenge of water scarcity in relation to agriculture through understanding farmers’ perceptions and adaptation measures to water scarcity as they are the forefront users of water. Through qualitative research approach, fieldwork interviews with rice farmers in Kafr El Sheikh governorate in Egypt and in-depth interviews with water management experts were conducted to identify farmers’ perceived causes of water scarcity and their adaptation behaviors and practices in relation to the broader policy context of water management. The study revealed that farmers’ perceived causes of water scarcity are related to inefficiency and inequity of the institutional and infrastructural governance of the irrigation system, which are exacerbated by the farmers’ socio-economic conditions (location, income, and social networks/influence). Farmers’ adaptation practices include reusing treated and untreated agricultural drainage water, shifting crops and changing crop varieties. Use of untreated drainage water poses an alarming national health hazard, which is important to address to ensure agricultural drainage water meets quality and safety standards. Findings also reveal the differentiated experience of adaptation capacities among farmers where socio-economic conditions could entail limited adaptation capacities. Farmers’ adaptation measures are thus considered temporary or short-term measures which imply that farmers’ coping strategies to water shortage are not systemic, but rather individualized and localized and do not manifest long-term, just, and sustainable change in a water-scarcity situation. The findings of this study also point out several policy limitations to supporting farmers adaptation to water scarcity and to the overall agricultural water management in Egypt. Lack of farmers’ participation, tokensim dynamic, and limited support channels are major features of the agricultural water management system, which hinder real and sustainable progress in irrigation efficiency and water management. Additionally, a policy dialogue disconnect between the government and other stakeholders is a clear feature in the broader policy context of Egypt’s water management. This is especially critical as alignment in the direction and efforts are detrimental to the efficiency and sustainability of water-related interventions both on a national and local level. Several policy recommendations are put forward to address farmers’ adaptation capacities, improvement in the irrigation system management and operations as well as sectoral development and the overall water policy direction in Egypt