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Ferrofluids are aqueous or non-aqueous solutions with colloidal particles of iron oxide nanoparticles with high magnetic characteristics. Their magnetic characteristics enable them to be controlled and manipulated when ferrofluids are exposed to magnetic fields. This study aims to inspect the features of unsteady stagnation point flow (SPF) and heat flux from the surface by incorporating ferromagnetic particles through a special kind of second-grade fluid (SGF) across a movable sheet with a nonlinear heat source/sink and magnetic field effect. The mass suction/injection and stretching/shrinking boundary conditions are also inspected to calculate the fine points of the features of multiple solutions.

The leading equations that govern the ferrofluid flow are reduced to a group of ordinary differential equations by applying similarity variables. The converted equations are numerically solved through the bvp4c solver. Afterward, study and discussion are carried out to examine the different physical parameters of the characteristics of nanofluid flow and thermal properties.

Multiple solutions are revealed to happen for situations of unsteadiness, shrinking as well as stretching sheets. Greater suction slows the separation of the boundary layers and causes the critical values to expand. The region where the multiple solutions appear is observed to expand with increasing values of the magnetic, non-Newtonian and suction parameters. Moreover, the fluid velocity significantly uplifts while the temperature declines due to the suction parameter.

The novelty of the work is to deliberate the impact of mass suction/injection on the unsteady SPF through the special second-grade ferrofluids across a movable sheet with an erratic heat source/sink. The confirmed results provide a very good consistency with the accepted papers. Previous studies have not yet fully explored the entire analysis of the proposed model.

This study intends to improve the quality of venous thromboembolism (VTE) prophylaxis practices including proper VTE risk assessment and the appropriate prophylaxis measures for surgical urology patients.

The authors applied the Six-Sigma define, measure, analyze, improve and control (DMAIC) improvement methodology in a pre–post interventional study that involved all adult patients above 18 years old indicated and scheduled for urology surgical interventions including endoscopic urological surgeries in a urology specialized 60-bed hospital. The pre-intervention sample included all patients meeting the inclusion criteria over a period of six months. Post-intervention sample included all patients meeting the inclusion criteria over a period of six months. The improvement areas included both the VTE risk assessment as well as the VTE prophylaxis prescription.

DMAIC methodology has achieved a substantial sustained improvement in surgical urology VTE prophylaxis practices with an average of 70% on both levels; VTE risk assessment practices and VTE prophylaxis prescribing practices were statistically significant. The post-intervention results also showed a statistically controlled process with no special cause variations. Based on the study results, the Six-Sigma DMAIC methodology can be considered of high value when applied in healthcare clinical practice improvement projects.

The project study includes some pitfalls that can be addressed as follows: 1. The lack of VTE rate incidence tracking. This limitation can be partly refuted when the authors conduct a literature review and explore that the VTE prophylaxis effectiveness had been proven with sufficient evidence to an extent that pushed several scientific societies to develop their own guidelines to support VTE prophylaxis. (Algattas et al., 2018). 2. Another limitation of this study can be that it handled only surgical patients and more specifically surgical urology patients. Of course, VTE prophylaxis is a crucial life-threatening problem not only for the surgical admitted patients but also for all the medical admitted patients either in hospital wards or ICUs. However, the prediction that surgical patients especially surgical urology patients are more prone to VTE development risk as they have -in several cases-two or three main additive risk factors which are age, procedure duration and malignancy in elderly men. (Tikkinen et al., 2014). So, the authors consider the study project to be a prototype that hopefully can be utilized for future study projects that will manage both other surgical specialty patients and medical patients on the national level and can track accurately and effectively report the VTE incidence rates.

Several recommendations can be extracted from the research project that is summarized in the following points: Paying focused attention to continuous healthcare quality improvement initiatives and projects as a main approach for healthcare improvement especially for the public health-related problems. This might be achieved through periodic region-specific or specialty-specific focus groups from which public health problems could be addressed and prioritized to be considered as a part of country healthcare campaigns regarding cost-utility and feasibility studies. The adoption of a system thinking approach in dealing with the improvement strategies; all efforts and resources are to be employed to achieve a common objective. This includes the generation of a national-wide electronic health information system that can aid in healthcare resource allocation and direct the healthcare efforts towards the most important, high-priority public health problems. Electronic national-wide health record is really an effort, and resources consuming activity, but actually, it's worth exerting efforts, and its valuable outcomes may be seen several years later. 3. Development of unified national specialized VTE prophylaxis pathways to standardize the patient-specific VTE prophylaxis plans. Standardization of healthcare pathways enables healthcare professionals to follow an evidence-based practice which will be reflected on the improvement of healthcare quality level, cost-effectiveness enhancement, and timely patient care on all levels especially in high critical areas like ER and ICU. 4. Incorporation of VTE prophylaxis costs in the universal health insurance diagnosis-related group (DRG) insurance packages and service pricing. Universal health insurance is a nationwide strategy that is aiming to cover all Egypt residents by the year 2030. Universal health insurance is being following the DRG reimbursement policy that is thought to control all the healthcare-associated costs so, the VTE prophylaxis costs shall be added as the main cost item to encourage all healthcare facilities to follow an evidence-based VTE prophylaxis pathway taking into consideration the high-risk patient categories who will definitely represent a high-cost burden on the long run if they suffer a VTE event.

DMAIC improvement methodology applications in healthcare are still relatively limited, especially on the clinical level. The study can be considered one of a kind in Egypt dealing with a comprehensive DMAIC methodology application on the clinical level.

The purpose of this paper is to consider the simultaneous flow of Casson Williamson non Newtonian fluids in a vertical porous medium under the influence of variable thermos-physical parameters.

The model equations are a set of partial differential equations (PDEs). These PDEs were transformed into a non-dimensionless form using suitable non-dimensional quantities. The transformed equations were solved numerically using an iterative method called spectral relaxation techniques. The spectral relaxation technique is an iterative method that uses the Gauss-Seidel approach in discretizing and linearizing the set of equations.

It was found out in the study that a considerable number of variable viscosity parameter leads to decrease in the velocity and temperature profiles. Increase in the variable thermal conductivity parameter degenerates the velocity as well as temperature profiles. Hence, the variable thermo-physical parameters greatly influence the non-Newtonian fluids flow.

This study considered the simultaneous flow of Casson-Williamson non-Newtonian fluids by considering the fluid thermal properties to vary within the fluid layers. To the best of the author’s knowledge, such study has not been considered in literature.

Despite the dramatic increase in construction toward additive manufacturing, several challenges are faced using natural materials such as Earth and salt compared to the most market-useable materials in 3D printing as concrete which consumes high carbon emission.

Characterization and mechanical tests were conducted on 19 samples for three natural binders in dry and wet tests to mimic the additive manufacturing process in order to reach an efficient extrudable and printable mixture that fits the 3D printer.

Upon testing compressive strength against grain size, compaction, cohesion, shape, heat and water content, X-Salt was shown to record high compressive strength of 9.5 MPa. This is equivalent to old Karshif and fire bricks and surpasses both rammed Earth and new Karshif. Material flow analysis for X-Salt assessing energy usage showed that only 10% recycled waste was produced by the end of the life cycle compared to salt.

Findings are expected to upscale the use of 3D salt printing in on-site and off-site architectural applications.

Findings contribute to attempts to resolve challenges related to vernacular architecture using 3D salt printing with sufficient stability.

Benefits include recyclability and minimum environmental impact. Social aspects related to technology integration remain however for further research.

This paper expands the use of Karshif, a salt-based traditional building material in Egypt's desert by using X-Salt, a salt-base and natural adhesive, and investigating its printability by testing its mechanical properties to reach a cleaner and low-cost sustainable 3D printed mixture.

This paper seeks to investigate to what extent (and why) CSR reporting in developing countries reflect instrumental and/or “political CSR” motivations and the types of organisational legitimacy sought in these circumstances.

We adopt a theoretical framework based on neo-institutional theory, “political CSR” framework and types of organisational legitimacy. This interpretive research is set in the Egyptian context post-2011 revolution. We first carry out a content analysis of web disclosures for 40 banks in 2013 and 2016 to ascertain the nature of CSR activities and any changes over time. Second, we draw on 21 interviews to tease out the implications of the change in societal expectations due to the revolution and to deepen our understanding of the organisational motivations underlying CSR reporting.

Following the 2011 revolution, the banks’ CSR reporting practices have gradually shifted from a largely instrumental “business-case” perspective towards a more substantive recognition of a wider set of societal challenges consistent with a political CSR perspective. Overall, the maintaining/gaining of legitimacy is gradually bound to the communication of accounts about the multi-faceted socially valued consequences or structures performed by banks. Our interview data shows that participants reflected on the legitimation challenges brought by the revolution and the limits of transactional strategies involving traditional constituents, with a preference for pursuing consequential and structural forms of moral legitimacy.

This study demonstrates a constructive shift by businesses towards engaging with the new social rules in response to sociopolitical changes and the need to achieve moral legitimacy. Hence, policymakers and stakeholders could consider engaging with different economic sectors to foster more transparent, accountable, and impactful CSR practices.

We highlight the implications of Scherer and Palazzo’s political CSR approach for accountability and CSR reporting. CSR reporting in some developing countries has typically been seen as peripheral or a symbolic exercise primarily concerned with placating stakeholders and/or promoting shareholders’ interests. We suggest that researchers need to be instead attuned to the possibility of a blend of instrumental and normative motivations.

The purpose of this paper is to investigate the emancipatory promises and realities of information and communication technology (ICT) in Egypt.

The combination of Habermasian and Foucauldian ideas implemented by a critical discourse analysis of the Egyptian Information Society Policy and interviews with employees of local decision support systems employees. Promises and rhetoric are contrasted with findings and questioned with regards to their validity.

On the policy level, analysis shows that the emancipating rhetoric of ICT is not followed through. ICT is mostly seen as a means of attracting foreign direct investment. Neither political participation nor educational benefits are promoted seriously. On the local level, culture and organisational realities prevent individuals from exploiting the emancipatory potential of the technology.

The combination of the Habermasian and Foucauldian approach exposes the problems of ICT use in developing countries. It shows that emancipation is used to legitimise ICT policies but is not taken seriously on a policy level in Egypt. Local implementations also fail to deliver on their promise. In order to have emancipatory effects, ICT policy and use will need to be reconsidered.

The purpose of this paper is to evaluate the performance of polypropylene glycol (PPG), as a corrosion inhibitor for aluminium corrosion in 0.5 M H₂SO₄ solution at 303-333 K and the effect of addition of iodide ions on the corrosion inhibition efficacy of PPG.

The corrosion inhibition performance of PPG alone and on addition of iodide ions in the acid medium was evaluated using weight loss and electrochemical [electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR) and potentiodynamic polarization (PDP)] methods as well as surface analysis approach at 303-333 K. The morphology of the corroding aluminium surface without and with the additives was visualised using scanning electron microscopy (SEM). The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

Results obtained showed that PPG moderately retarded the corrosion of Al in 0.5 M H₂SO₄ solution. Addition of KI to PPG is found to synergistically improve the inhibitive ability of PPG. From the variation of inhibition efficiency, K_ads, and E_a, with rise in temperature, physisorption mechanism is proposed for the adsorption of PPG and PPG + KI onto the Al surface in 0.5 M H₂SO₄ solution. Polarisation results showed that PPG and PPG + KI acted as mixed type inhibitor. The adsorption of PPG and PPG + KI, respectively, onto the metal surface followed El-Awady et al. adsorption isotherm model. SEM and water contact angle analysis confirmed the adsorption of PPG and PPG + KI on Al surface.

The research is limited to aqueous acid environment in aerated condition, and all tests were performed under static conditions.

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

The investigations provide a basis for the optimization of the alloy 6061-T6 friction stir welding (FSW) process to improve the mechanical properties of welded joints.

The local deformation of the FSW joint in tension and fatigue test were experimentally investigated by digital image correlation (DIC) technique.

The local stress-strain behaviors of the sub-regions show that the plastic strain always concentrated at the heat affected zone (HAZ) on the advancing side both in tension and high cycle fatigue and eventually leads to the final fracture. The evolution of the plastic strain at very low stress is extremely slow and accounts for most of the total fatigue life. However, the local deformation exhibits a sudden increase just before the fatigue failure.

Based on the experimental data, the result indicates that the HAZ is the weakest zone across the weld and the strain localization in high cycle fatigue is very harmful and unpredictable for the FSW joints.

In this study, corrosion behavior of X53CrMnNiN219 austenitic stainless steel (SS) and X45CrSi93 martensitic SS, as well as the galvanic corrosion produced by coupling of these dissimilar alloys, are evaluated in a 3.5 Wt.% NaCl solution at temperature 25°C ± 1°C.

The corrosion parameters were estimated through a series of electrochemical tests, including Tafel polarization, electrochemical impedance spectroscopy (EIS), and zero-resistance ammeter (ZRA) technique.

The results of polarization measurements indicate that the value of corrosion current in the galvanic pair is slightly higher than that of both the austenitic and martensitic SS during the initial time of immersion in the chloride solution, which is an indication of compatibility of members in the couple. The galvanic current density measured by ZRA technique shows negative values throughout the test; accordingly, the martensitic SS acts as anode of the pair and corrodes preferentially. Localization index values are limited to the mixed corrosion process, showing relative susceptibility of the martensitic alloy to the uniform and localized corrosion (pitting) due to chloride ions.

The originality is the evaluation of galvanic corrosion susceptibility of X53CrMnNiN219 and X45CrSi93 SSs in chloride solution by the various electrochemical methods consisting of Tafel polarization, EIS, and (ZRA) technique. To our knowledge, no work has been reported on this issue for these chemical compositions under this condition up to now.