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Arab early career researchers (ECRs) are strongly encouraged to actively participate in scholarly communication activities, as it not only enhances their academic standing but also facilitates career advancement and garnering recognition from both the scientific community and the broader public. Nevertheless, the constantly evolving landscape of scholarly communication has imposed significant challenges on researchers. This paper is dedicated to an examination of the scholarly communication practices of early career researchers in Egypt, with the overarching objective of providing insights into the transformations occurring within the scholarly communication framework, particularly within the context of developing nations. In our paper, we employed a quantitative research design to scrutinize the scholarly communication system in Egypt. This endeavor encompassed the distribution of questionnaires to early career researchers hailing from prominent Egyptian universities, resulting in a total of 441 respondents representing various academic institutions across the country. Our analysis revealed that junior scholars predominantly adhere to conventional scholarly methodologies in their research pursuits. This conformity is, in part, attributed to the promotion system in Egypt, which places considerable emphasis on established practices, such as single-author publication, while discouraging the utilization of informal channels for garnering recognition and accolades. The findings of this study furnish us with a more profound comprehension of the prevailing scholarly system in Egypt, which in turn can serve as a foundation for potential system enhancement. It is imperative to acknowledge, however, that this study is not without limitations. The response rate could not be precisely quantified due to the online dissemination of the questionnaires, and the distribution of respondents across diverse scholarly disciplines exhibited significant disparities. [ABSTRACT FROM AUTHOR]

This study evaluated the entrepreneurial culture in Omani university libraries and analyzed the benefits and difficulties that come with it. The main aims was to examine the resources and guidance offered by these libraries for creating an entrepreneurial culture as well as the perceived challenges faced by library staff and students. The study also tried to identify effective programs and top practices from other academic libraries that might be applied to the Omani context. A combination of semi-structured interviews with staff members from five libraries and surveys given to students in 10 libraries were used to accomplish these goals. The results of this study showed that the Sultanate of Oman's academic libraries actively support entrepreneurial culture and are aware of their potential as centres for its diffusion. They do, however, face challenges, such as a dearth of competent workers in the field of business and a lack of pertinent collections to support the entrepreneurial culture. The study also emphasized the need for Omani academic libraries to improve the services they offer in the area of entrepreneurship and spread knowledge of its significance, particularly in light of the nation's sustainable development aspirations. By contributing to understanding entrepreneurial culture within the context of Omani academic libraries, this research provides valuable insights for library professionals, educators, and researchers. It identifies current challenges and opportunities and shares successful initiatives from other academic libraries, emphasizing the significance of fostering an entrepreneurial mindset in academic libraries to promote innovation and contribute to the overall advancement of the library industry and information institutions in the Arab world. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to report the findings of a study of library anxiety among a group of Arab students in Saudi Arabia and Egypt. The paper also investigated the factors that affect the students' level of anxiety while using academic libraries. The study tried to compare the difference in the level of anxiety in the two countries using a scale (LLPB) developed by the researchers which fit the culture in the Arab region. The study adopted a mixed methods approach. Semi-structured interviews were conducted with several students in Saudi Arabia and Egypt to determine the main factors that lead to having a level of anxiety in the libraries. In the second stage, a questionnaire was sent to students to measure what factors have a greater impact on the level of anxiety. The data showed that Egyptian students are more anxious about using the libraries than the Saudi students. The results also indicated that there is a need to train students on how to use the libraries and also change students' perception regarding the library to reduce the level of anxiety. This study was conducted in Egypt and Saudi Arabia the level of library anxiety and the factors that may affect the students may vary in other countries. [ABSTRACT FROM AUTHOR]

This study aimed to identify factors associated with neurological and disability outcomes in patients who underwent ECMO following cardiac arrest. This retrospective, single-center, observational study included adult patients who received ECMO treatment for in-hospital cardiac arrest (IHCA) or out-of-hospital cardiac arrest (OHCA) between February 2016 and March 2020. Factors associated with neurological and disability outcomes in these patients who underwent ECMO were assessed. Hamad General Hospital, Qatar. Neurological disability outcomes were assessed using the Modified Rankin Scale (mRS) and the Cerebral Performance Category (CPC) scale. Among the 48 patients included, 37 (77 %) experienced OHCA, and 11 (23 %) had IHCA. The 28-day survival rate was 14 (29.2 %). Of the survivors, 9 (64.3 %) achieved a good neurological outcome, while 5 (35.7 %) experienced poor neurological outcomes. Regarding disability, 5 (35.7 %) of survivors had no disability, while 9 (64.3 %) had some form of disability. The results showed significantly shorter median time intervals in minutes, including collapse to cardiopulmonary resuscitation (CPR) (3 vs. 6, P = 0.001), CPR duration (12 vs. 35, P = 0.001), CPR to extracorporeal cardiopulmonary resuscitation (ECPR) (20 vs. 40, P = 0.001), and collapse-to-ECPR (23 vs. 45, P = 0.001), in the good outcome group compared to the poor outcome group. This study emphasizes the importance of minimizing the time between collapse and CPR/ECMO initiation to improve neurological outcomes and reduce disability in cardiac arrest patients. However, no significant associations were found between outcomes and other demographic or clinical variables in this study. Further research with a larger sample size is needed to validate these findings. The study underscores the significance of reducing the time between collapse and the initiation of CPR and ECMO. Shorter time intervals were associated with improved neurological outcomes and reduced disability in cardiac arrest patients. [ABSTRACT FROM AUTHOR]

The current study coupled fabric phase sorptive extraction (FPSE) with ultraperformance liquid chromatography method with electrospray ionization and tandem mass detection (UPLC-ESI-MS/MS) for fast and sensitive determination of tadalafil (TAD) in a bioequivalence study. Fabric phase sorptive extraction allowed direct extraction of TAD from the sample matrix with improved selectivity, repeatability, and recoveries. A sol–gel Carbowax 20 M (CX-20 M) coated FPSE membrane revealed the best extraction efficiency for TAD because of its strong affinity for analytes via intermolecular interactions, high mass transfer rate to FPSE membrane, and high permeability. An automated multiple reaction monitoring (MRM) optimizer was employed for the best selection of the precursor and product ions, ion breakdown profile, the fine adjustment of the fragmentor voltages for each precursor ions, and the collision energies for the product ions. The chromatographic separation was conducted using a mobile phase A: 5.0 mM ammonium acetate with 0.1 % formic acid in water and mobile phase B: formic acid (0.1%) in acetonitrile in ratio (55:45, v/v) through isocratic elution mode on an Agilent EclipsePlus C18 (50 × 2.1 mm, 1.8 μm) column and the flow rate was adjusted at 0.4 mL min−1. The total run time per sample was 1.0 min. The method was validated by FDA standards for bioanalytical method validation over a concentration range of 0.1–100 ng mL−1 with a correlation coefficient of 0.9993 and the lower limit of quantitation (LLOQ) was 0.1 ng mL−1 in rat plasma. Intra- and inter-assay precision (%RSD) were lower than 4.1% and accuracy (%RE) was within 2.4%. The developed FPSE-UPLC-ESI-MS/MS method was effectively used in a randomized, two-way, single-dose, crossover study to compare the bioequivalence of two TAD formulations from different companies in male rats and verified to be bioequivalent. [ABSTRACT FROM AUTHOR]

A major challenge to wind turbine design is enlarging their blades to harness more power. However, aerodynamic loads can cause blades to deflect, flutter and possibly fail. Humpback Whales do not have this problem, despite their large size, due to the presence of tubercles on their flippers. This study investigates the design of bio-inspired tubercles on the leading edge of wind turbine blades to minimize deflection and maximize power capture. CFD and fluid-solid interaction models were developed and validated for the WindPACT 1.5-MW baseline blade to simulate the wind flow and deflection before and after adding the tubercles. A first and second law analysis was conducted to investigate the optimum tubercle design. The results showed a stress concentration and maximum tip deflection affecting the baseline blade of 74.57 MPa and 1.51 m, respectively. The applied tubercles of 2.5% height and 50% length of the chord length achieved better characteristics by reducing the blade's deflection by 16.4%. By implementing the tubercles, the blades' length can be increased by 25% to achieve a 65% improvement in captured torque at an equal deflection to the smaller baseline blade. This confirmed the improved blade performance using the bio-inspired tubercle leading edges. • Bio-inspired tubercles are investigated to reduce wind turbine blades deflection. • An energy and exergy analyses are performed to investigate the tubercle design. • The optimum tubercle design reduces the blade's deflection by 16.4%. • Torque capture improves by 65% at the original deflection for a 25% longer blade. [ABSTRACT FROM AUTHOR]

• THE COMBINATION OF Enteric duplication and intestinal malrotation IS rare but can coexist. • Malrotation MUST BE kept in mind in patients with preoperatively diagnosed duplication cyst. • Surgical correction in form of A LADD's procedure and resection of THE duplication WITH anastomosis IS CURATIVE. • Ultrasound seems TO BE a good diagnostic tool for THE PREOPERATIVE diagnosis of both conditions. Both Enteric duplication and intestinal malrotation are concerning causes for intestinal obstruction in the pediatric age group and they very rarely coexist in the same patient. We present 2 cases of previously healthy children, the first is a 4-month-old infant and the second is a 1.5-year-old boy, both presented with recurrent attacks of bilious vomiting that proved to be due to acute midgut volvulus caused by an enteric duplication cyst associated with intestinal malrotation. Enteric duplication and intestinal malrotation are two of the concerning causes of billious vomiting in the pediatric age group. They could be encountered at any level of the alimentary tract from the tongue to the anus. The term malrotation refers to all abnormalities of intestinal position. The coincidence of intestinal malrotation and an enteric duplication cyst (EDC) is very rare and has been described only in a few case reports. The concomitance of EDC and intestinal malrotation is extremely rare and should be kept in mind in a child presenting with bilious vomiting especially in a child preoperatively diagnosed with a duplication cyst. [ABSTRACT FROM AUTHOR]

• Cecal volvulus is a very rare cause of intestinal obstruction in children. • Novel association between Congenital dilated cardiomyopathy and cecal volvulus. • Cecal volvulus should be suspected in a child presenting with bilious vomiting. Cecal volvulus is an extremely rare cause of intestinal obstruction in the pediatric age group and its incidence is unknown. We present a unique case of cecal volvulus in a 3 year old female with congenital dilated cardiomyopathy. Cecal mobility due to malfixation and malrotation is the main cause. Cecal Volvulus usually presents with constipation, abdominal pain and distention. Common complications entail strangulation, ischemia and gangrene. Cecal volvulus has been reported in association with various abnormalities. However, Incidence of cecal volvulus in a child with congenital dilated cardiomyopathy has not been reported. Surgery is the mainstay of management. Cecal volvulus should be kept in mind in a child presenting with signs suggestive of intestinal obstruction. [ABSTRACT FROM AUTHOR]

Wells turbine is the simplest type of an axial flow self-rectifying air turbine that can be used in conjunction with Oscillating Water Column (OWC) system in the extraction of ocean wave energy. It has been noticed that this turbine is subjected to early stall. As a consequence, several attempts for improving the energy extraction performance of Wells turbine within the stall regime have been investigated. One of these attempts was using an inclined slot as a passive flow control to obtain a delayed stall. In the following study, the impact of varying the angle for the slot on the performance of Wells turbine in the stall regime was investigated. Furthermore, the first law of thermodynamics and the entropy analysis has been used to examine the effect of the slot angle on the entropy generation features around the turbine blade. Moreover, Investigation of slot angle effect on the aerodynamics noise emission from Wells turbine airfoil during the normal operation and the stall regime is covered in this study. The blade of turbine with optimum angle of slot was investigated using the OWC based on actual data from the Egyptian Northern Coast. It was found that the optimum slot angle is 10° clockwise which results in 3% improvement in the torque coefficient before the stall and 15% after the stall as compared to the 0° slot. Otherwise, it gives a lower global entropy generation rate than the 0° slot by 4% before the stall and 3% after the stall. Furthermore, using airfoil of blade turbine with a slot resulted in a reduction of aeroacoustic noise by −21.2% at the stall regime under oscillating flow conditions. [ABSTRACT FROM AUTHOR]

With great interest, the authors have read the comments made by Ghisu et al. on our recent paper [1] published in Renewable Energy. The comments severely criticizes our methodology and results, which actually provide us with fortunate opportunity to discuss our work in more details to complement our work, thankfully to this available space of scientific discourse provided by Renewable Energy editors. In this reply, we show clearly that all the comments proposed by Ghisu et al. lacks sufficient understanding of Wells turbine modeling approaches, literature, and state of the art research practices. We also show that Ghisu et al. could not distinguish between fully developed turbulent flow and transitional flow around Wells turbine airfoils. It is also evidently shown that their concerns about the entropy generation calculation method are meaningless in the light of well-established practices of CFD models of entropy generation minimization principles. Our reply is structured in a point-by-point style to address the comments raised in the discussion article and help the readers understand our work in better details. [ABSTRACT FROM AUTHOR]

In this work, the passive flow control method was applied to improve the performance of symmetrical airfoil section in the stall regime. In addition to the commonly used first law analysis, the present study utilized an entropy generation minimization method to examine the impact of the flow control method on the entropy generation characteristics around the turbine blade. This work is performed using a time-dependent CFD model of isolated NACA airfoil, which refers to the turbine blade, under sinusoidal flow boundary conditions, which emulates the actual operating conditions. Wells turbine is one of the most proper applications that can be applied by passive flow control method because it is subjected to early stall. Additionally, it consists of a number of blades that have a symmetrical airfoil section subject to the wave condition. It is deduced that with the use of passive flow control, torque coefficient of blade increases by more than 40% within stall regime and by more than 17% before the stall happens. A significantly delayed stall is also observed. [ABSTRACT FROM AUTHOR]

Wave energy has a great potential to solve the unrelenting energy deficiency in Egypt. The present work recommends Wells turbine as a suitable choice for the Egyptian coasts due to its simple and efficient operation under low input air flow. In addition, the possibility of extracting the wave energy from the Egyptian coasts was investigated using the oscillating water system based on real data from the site. To achieve this purpose, two-dimensional numerical models for Wells turbine airfoils, functioning under sinusoidal wave flow conditions, were built. Moreover, the running and starting characteristics under sinusoidal-flow conditions were investigated using a mathematical code. The results were discussed using the first law analysis, in addition to the second law analysis by using the entropy generation minimization method. It was found that the NACA0015 airfoil always gives a global entropy generation rate that is less than other airfoils by approximately −14%, −10.3% and −14.7% for the sinusoidal wave with time periods equal to 4, 6 and 8 s respectively. Moreover, the effects of blade profile, time period and solidity on the output power (kW) value were discussed. [ABSTRACT FROM AUTHOR]

Museums are the cultural interface of every nation. Creating and maintaining museums has been a national obligation to preserve and protect their inherited culture. An open museum is a special type of museums, which is usually initiatedin locations with huge architectural and urban heritage that cannot be otherwise accommodated in a building. They introduce a mixed image of the past and present, and help develop cultural and heritage tourism in an area. Thisresearch argues that museums, especially the open ones are good and effective tools to preserve urban heritage, maintain the history and culture, and encourage sustainable tourism.Makkah city is one of the oldest cities in the world. It has hundreds of memorable historic locations. As a city, Makkah has its unique diversity of culture and heritage. Being the birthplace of Islam, Makkah has a special image in the minds of billions of Muslims around the world. In view of the big development plans that cover the entire city, and which are expected to affect every aspect of its rich cultural heritage,preserving the historic locations has become even more significant. Since the development projects are likely to endanger the existence of historic locations in Makkah city, the paper proposes to create areas within the city as preserved historic locations and to develop them as open museums. The paper argues that this proposal will help create a sustainable tourism industry in the city in addition to the existing Hajj and Umrah business activities.Finally the paper concludes with recommendations to preserve and protect the Makkah heritage in a sustainable manner. [ABSTRACT FROM AUTHOR]

This study focuses on enhancing the attenuation properties of bentonite clay using powdered iron and ferrosilicon. Scanning electron microscopy and X-ray diffraction analysis were used to characterize the prepared samples. The linear attenuation coefficient was calculated experimentally for the prepared samples using a NaI scintillation detector and four radioactive point sources (Am-241, Cs-137, Co-60, and Eu-152). These results were in good agreement with the compared with the XCOM results. Other radiation shielding parameters, such as the half-value layer, mean free path, and radiation protection efficiency, were determined. Furthermore, at a photon energy of 0.06 MeV, the half-value layers were 0.276 and 0.628 cm for bentonite–iron and bentonite–ferrosilicon, respectively. The results indicate that the radiation shielding efficiency of bentonite–iron composites is better than that of bentonite–ferrosilicon composites at low and intermediate gamma-ray energies. • The shielding capability of the pure bentonite clay and the clay with additives. • Using X-COM data to confirms the accuracy in the setup used in this study. • Iron or ferrosilicon as additives in the clay improve the attenuation coefficients. • Additive type at the same concentration effects the radiation protection efficiency. [ABSTRACT FROM AUTHOR]

Wells turbine concept depends on utilizing the oscillating air column generated over marine waves to drive a turbine. As a matter of fact, previous researches on the performance analysis of such turbine were based on the first law of thermodynamics only. Nonetheless, the actual useful energy loss cannot be completely justified by the first law because it does not distinguish between the quantity and the quality of energy. Therefore, the present work investigates the second law efficiency and entropy generation characteristics around different blades that are used in Wells turbine under oscillating flow conditions. The work is performed by using time-dependent CFD models of different NACA airfoils under sinusoidal flow boundary conditions. Numerical investigations are carried out for the incompressible viscous flow around the blades to obtain the entropy generation due to viscous dissipation. It is found that the value of second law efficiency of the NACA0015 airfoil blade is higher by approximately 1.5% than the second law efficiency of the NACA0012, NACA0020 and NACA0021 airfoils. Furthermore, it is found that the angle of attack radically affects the second law efficiency and such effect is quantified for NACA0015 for angle of attack ranging from −15° to 25°. [ABSTRACT FROM AUTHOR]

The present work provides a preliminary study to clarify the geological setting and petrophysical potential of the offshore Temsah gas field, which is located as a NW–SE trending anticlinal structure. In the Temsah gas field, the main target is the Serravallian Sidi Salem sandstones while the second target is the Tortonian Wakar Formation. The Sidi Salem Formation produces gas and condensates from three main sand lobes, while Wakar Formation produces from some sand interbeds. The seismic velocity in Temsah gas field was a major problem due to the complexity of the structural and stratigraphic setting, and the existence of a strong pattern of multiples generated by the Rosetta evaporites at the top of the Miocene sequence. In the present study, an integrated interpretation was applied for the available well logs and the subsurface geological data as well as some available seismic sections. The highest hydrocarbon potential in the Sidi Salem sand lobes has been assigned for sand lobe III, which has the largest net pay thickness and the best petrophysical properties, particularly in the southern to the northern central wells across the crest of the structure. The basin depocenter extends along the central parts through Temsah-1, -2, -3 and -8 wells. The maximum average effective porosity values of the Sidi Salem reservoir were recorded in Temsah-5 and Temsah-1 wells (27% and 30%, respectively), to the northwestern and southeastern parts of the field at the crest of Temsah anticlinal structure, while the considerable porosity values of the Wakar reservoir were measured in the southern wells. Permeability of the Wakar reservoir increases with increasing porosity and decreases with increasing the water saturation, whereas for the Sidi Salem reservoir, permeability is dependent on porosity rather than the water saturation. The minimum average water saturation values for Sidi Salem and Wakar reservoirs were recorded in the central parts of the field (25% and 30%). The shale volume in both reservoirs is not effective (smaller than 13%). In general, the net oil column of Sidi Salem reservoir wells indicates a better reservoir quality for Temsah-1, Temsah-3, and Temsah-7 wells (the net pay varies in thickness from 48 to 69 m) at the crest of Temsah anticlinal structure to the north and central west of the field; while for Wakar reservoir it indicates a better quality in Temsah-3 well (9.0 m) to the north of the field. [ABSTRACT FROM AUTHOR]

• A numerical model is developed to study the cascaded failure of transmission lines under downbursts. • An extensible catenary approach is utilized to predict the tension forces developed in the conductors. • The post failure geometry of the towers within the line is predicted. • A segment of an existing transmission line is considered as a case study. Transmission line's cascades have played a major role in several serious accidents around the world, as they are particularly prone to occurring in the presence of strong winds. The failure of a line component overloads the system, inducing a progressive failure that can involve many transmission line (TL) supports. Due to their localized nature, downbursts, in particular, cause unequal wind forces on various towers of a transmission line; the collapse of one tower can affect the adjacent towers through the unbalanced forces that develop in the conductors, which can lead to a cascaded-type of failure along the entire line. In this study, a numerical model is developed in-house to predict this type of line failure. A major challenge in this numerical model is the prediction of the geometric configuration of the tower and of the conductor forces after the tower collapses. Details of this unique numerical model are presented in this paper along with a case study for illustration. [ABSTRACT FROM AUTHOR]

The present work analyzes, through a rigorous numerical investigation, the entropy generation due to viscous dissipation around a Wells turbine blade. Two-dimensional numerical models for four NACA airfoils were built and validated against experimental measurements under steady flow conditions. The models were used to assess the entropy generation for flows achieving 10o angle of attack. It was found that the entropy generation around the NACA0015 airfoil blade is less by approximately 12% than the entropy generation around NACA0012, NACA0020 and NACA0021 airfoils. Then, the NACA0015 and NACA0021 airfoils were simulated under different flow conditions (i.e. Reynolds number and angle of attack). The results were discussed in the light of Wells turbine performance objectives. [ABSTRACT FROM AUTHOR]

Hydrokinetic energy uses the flowing water of the riverine systems to generate electrical power. The technology is used to meet the green energy requirements in remote villages, to provide power for the isolated areas and factories with a small utility scale. The present study aims to conduct an analysis of the Egyptian riverine systems for remote areas. Numerical analysis is applied using the URANS model. Verification and validation had been implemented with the proper boundary condition. Five ducted airfoils have been simulated around the hybrid Savonius-Darrieus current turbine as an augmentation technique. The ducted airfoils are NACA-0012, NACA-0015, NACA-0018, NACA-0021, and NACA-0024. The study concluded that the optimal ducted airfoil is the NACA-0015. The hybrid turbine had an average power coefficient of 0.114. Also, the first and the second laws of efficiencies were revealed, for the NACA-0015, of 64.9% and 83.4% respectively. • Five ducted airfoils have been investigated around Savonius-Darrieus current turbine. • The model applied the Egyptian riverine systems boundary conditions. • The optimal ducted airfoil was the NACA-0015. • The average power coefficient for the turbine with optimal ducted airfoil was 0.114. • The first and the second laws of efficiencies were 64.9% and 83.4% respectively. [ABSTRACT FROM AUTHOR]

Abstract: Type 1-diabetes is an autoimmune disease, where a chronic inflammatory process finally causes β-cell death and insulin deficiency. Extracts from gum resin of Boswellia serrata (BE) have been shown to posses anti-inflammatory properties especially by targeting factors/mediators related to autoimmune diseases. Multiple low dose-streptozotocin (MLD-STZ) treatment is a method to induce diabetes in animals similar to Type 1 diabetes in humans. It was aimed to study whether or not a BE could prevent hyperglycemia, inflammation of pancreatic islets and increase of proinflammatory cytokines in the blood in MLD-STZ treated mice. In BK+/+ wild type mice, 5days of daily treatment with 40mg/kg STZ i.p. produced permanent increase of blood glucose, infiltration of lymphocytes into pancreatic islets (CD3-stain), apoptosis of periinsular cells (staining for activated caspase 3) after 10days as well as shrinking of islet tissue after 35days (H&E staining). This was associated with an increase of granulocyte colony stimulating factor (G-CSF), granulocyte/macrophage colony stimulating factor (GM-CSF) and proinflammatory cytokines (IL-1A, IL-1B, IL-2, IL-6, IFN-γ, TNF-α) in the blood. Whereas BE alone did not affect blood glucose in non diabetic mice, in STZ treated mice simultaneous i.p. injection of 150mg/kg of BE over 10days prevented animals from increase of blood glucose levels. Histochemical studies showed, that i.p. injection of 150mg/kg BE for 10days starting with STZ treatment, avoided lymphocyte infiltration into islets, apoptosis of periinsular cells and shrinking of islet size 35days after STZ. As far as the cytokines tested are concerned, there was a significant inhibition of the increase of G-CSF and GM-CSF. BE also significantly prevented the increase of IL-1A, IL-1B, IL-2, IL-6, IFN-γ and TNF-α. It is concluded that extracts from the gum resin of Boswellia serrata prevent islet destruction and consequent hyperglycemia in an animal model of type 1 diabetes probably by inhibition of the production/action of cytokines related to induction of islet inflammation in an autoimmune process. [Copyright &y& Elsevier]

Hybrid wind wave farm systems integrate their capabilities to have higher and more reliable synergy than conventional renewable energy plants. The energy extractors' array layout is a pivotal factor for the output power. The aim of this work is to quantify the benefits of combining the wave energy and wind energy into a hybrid system on the Egyptian Mediterranean North Coasts. It also aims to investigate the optimal array layout of a hybrid wind wave energy farm. Numerical analyses using the RANS model are applied to different cases regarding the array layout and spacing in order to increase their performance. The results indicate that the most optimal array layout is a square-staggered one with a spacing of 4.0 rotor diameters along the y -axis and 5.0 rotor diameters along the x -axis. The revealed optimal layout provides more than a 14.4% increase in performance for the wind and wave arrays compared to an existing offshore wind farm, with 52.5% lesser farm occupying-surface area. [ABSTRACT FROM AUTHOR]

• Work advances state-of-the-art on RCP via calibrated and validated 3D numerical models. • Predictive models proven accurate using full-scale experimental results. • Model predicted behavior of RCP with single, double and triple cage reinforcing configuration. • Parametric study captured effects of reinforcement area, yield, cover, and position. • No other triple-cage RCP model could be presently found in open literature. • Models could form the basis for future RCP design charts. Reinforced Concrete Pipe (RCP) is widely used in storm and wastewater management owing to its resiliency and reliability. This study proposes nonlinear 3D finite-element models (FEMs) to explore the effects of reinforcement configuration on RCP structural performance. RCP having 825-mm, 1200-mm, and 1800-mm in diameter with the three reinforcement configurations commonly used by industry, namely single-cage, double-cage, and triple-cage, were modelled for evaluating 65D, 100D, and 140D pipe design classes. FEM predicted load–deflection was validated using experimental results on full-scale RCP specimens. Average FEM prediction error of service and ultimate loads was 6.8% and 6.3%, respectively. FEM stress contours suggested agreement with experimental observations. The development of stress in the concrete and steel reinforcement during the there-edge bearing test (TEBT) was evaluated and discussed. A thorough parametric analysis was performed on developed single and double-cage FEMs and demonstrated that the influence of the reinforcement area, cover, positioning, and yield strength on RCP behavior could be rationally captured by the numerical models. [ABSTRACT FROM AUTHOR]

• A catenary approach is utilized to analyze transmission line's conductors. • The approach considers the insulator's flexibility and the in plane and out of plane loading. • Accuracy of the derived approach is verified using finite element analysis. • The behavior of the conductors of transmission lines under downbursts is studied. The objective of this paper is to develop a mathematical approach that can predict the structural performance of a cable with end points unaligned both vertically and horizontally. The approach takes into account the extensibility of the cable. Moreover, it considers the analysis of a multiple span cable, the flexibility of the cable's supports and the effect of both in plane and out-plane loads. An important application of this model is related to the performance of transmission line conductors under High Intensity Wind (HIW) such as downbursts. The localized nature of those events can lead to failure of one tower, which results in misalignment of the end points of the adjacent spans. The developed model can be used in predicting the performance of an entire line post the failure of one tower during a downburst event. The validation of this mathematical model is conducted by comparing its numerical predictions to the results of the analysis of multi-span conductors conducted using non-linear Finite Element Analysis (FEA). The main advantage of the mathematical model compared to FEA is the efficient computational time, which is very important for predicting the progressive failure of transmission lines under downbursts as this requires conducting a large number of analyses by varying the location and size of the localized wind event. [ABSTRACT FROM AUTHOR]

Despite the fact that levodopa has proven its effectiveness in treating the symptoms of Parkinson's disease (PD), increasing concerns have emerged about its possible long-term toxic effects on dopamine (DA) neurons. The study investigated the possible ameliorative effect of virgin coconut oil against l -dopa- induced neurotoxicity in adult rats. A total number of 40 rats were divided into four groups. Briefly, the first served as control, the second was orally administered virgin coconut oil (1.42 mL/kg), the third group was administered a single daily dose of l -dopa/carbidopa (100/10 mg/kg/day, p.o) and the fourth group pre-treated with virgin coconut oil then administered a single daily dose of l -dopa/carbidopa. The different treatments were extended for 30 days. l -dopa treated group exhibited aggressive behavior and behavioral abnormalities in open field test compared to control group. In addition, l -dopa treatment caused significant increase in the levels of striatal dopamine and norepinephrine and their metabolites with concomitant decrease of serotonin and its metabolite. Moreover, l -dopa treatment increased histamine and GABA levels. In addition, l -dopa treatment induced oxidative stress and energy crisis. The histological and immunohistochemical studies showed that l -dopa caused a remarkable neurodegeneration and increased glial fibrillary acidic protein (GFAP) immunoexpression in the striatal area. Virgin coconut oil co-treatment significantly minimized the harmful effects of l -dopa. In conclusion, the present study revealed that virgin coconut oil provided a notable protection against l -dopa's untoward effects. [ABSTRACT FROM AUTHOR]

Understanding the effect of misalignment and microgeometry is important for gear designers and those have the main interest is gear manufacturing and maintenance. Unavoidable misalignment and microgeometry are both important factors to be considered in gear design which influence the resulted stresses, transmission error, and dynamic response. Analyzing the stress concentration on the tooth root and tooth flank areas is important to predict the failure modes that may occur. The current research work concentrates on modeling engaged gear teeth, analyzing the generated stresses and shows the importance of introducing the micro-geometry modifications. To do so, three different cases have been studied. The first case (case 1) considers the basic microgeometry modifications, the second case (case 2) considers the misalignment effect, and the last case (case 3) is to add some more micro-geometry modifications to compensate for the misalignment effect. It was observed that the gear calculating tools resulted in significantly higher stresses than the FE software. The obtained results from different software tools have been discussed to understand the differences for the three studied cases. However, the results from case 2 as compared to case 1 showed that the introduced misalignment results in shifting the stress pattern into one side of the gear tooth and significantly higher stresses than case 1. Case 3 showed that the use of micro-geometry modifications can result in compensating the effect of the misalignment in operation. • Modeling the effects of misalignment and microgeometry. • Using three software tools in modeling; FE-Abaqus, LDP and KISSsoft. • Stresses and transmission error are affected by introducing misalignment and microgeometry. • Stresses and transmission error are also affected by using different software tools. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate, discriminate and delineate the geological and petrophysical situation of Oligocene reservoir wells at Salamat-1 and Atoll-1 in North Damietta offshore concession in the Mediterranean Sea. It deals with a combined interpretation of the core analysis (density, porosity, permeability and mercury injection capillary pressure 'MICP') and petrography data (thin sections, scanning electron microscope and X-ray diffraction) as well as well log (gamma ray, density, neutron, micro spherical logs 'MSFL', shallow and deep resistivity, and Modular Formation Dynamic Tester logs) and the subsurface geologic data, as well as some available seismic sections to clarify the geological and the petrophysical characterization of the Oligocene unconventional tight sandstone gas reservoir, Salamat structure, North Damietta offshore, Mediterranean Sea, Egypt. Petrophysically, the studied sandstone core samples can be summed up into two reservoir rock types (RRT), where poor reservoir quality is assigned to one group while the other is characterized by tight reservoir properties. These two RRTs are discriminated into four microfacies, two arenite groups and two wacke groups. Filling the pore spaces with detrital clays are the most important reservoir quality-reducing factors. The seismic data indicates that the studied area is composed of Rupelian-Chattian multi-channel system located off shore with many sand channels distributed in the area. The Lower and Upper Chattian sand channels comprise the most important reservoir bodies in Atoll-1 well to the northeast of the study are gas-bearing bodies, whereas the Rupelian sand channels to the northwest at Salamat-1 well are the most important gas-bearing channels. Integration between the available core and well log data indicated that the best storage and flow capacity are assigned to the other water-bearing sand channels rather the gas-bearing channels in both Salamat-1 and Atoll-1 wells. • The Rupelian-Chattian multi-channel sandstones are the target of this study. • Delineate the geological and petrophysical situation of Oligocene clastic reservoirs. • Petrophysically, two reservoir rock types can be assigned in the studied sequence. • Petrographically, the studied samples are discriminated into four microfacies. • Filling the pore spaces with detrital clays is the main reservoir quality-reducing factor. [ABSTRACT FROM AUTHOR]

Wells turbine is the most common type of self-rectifying air turbine employed by Oscillating Water Column (OWC) wave energy devices due to its technical simplicity, reliability, and design robustness. Because it subjected to early stall, there were many endeavors to improve the energy extraction performance of Wells turbine within the stall regime. Using the multi suction slots as a passive flow control can help obtaining a delayed stall. Two, three and four suction slots were investigated to improve the performance of Wells turbine in the stall regime. In addition the commonly used first law analysis, the present study utilized an entropy generation minimization method to examine the impact of the multi suction slots method on the entropy generation characteristics around the turbine blade. The turbine blade with optimum suction slots number and location was investigated using the oscillating water system based on the real data from the site. To achieve this purpose, two-dimension numerical models for Wells turbine airfoils under sinusoidal wave flow conditions were built and analyze using (ANSYS FLUENT) solver. It is found that the airfoil with three suction slots located at 40%, 55% and 90% from leading edge in chord percentage give the highest torque coefficient by 26.7% before the stall and 51% after the stall. [ABSTRACT FROM AUTHOR]

Savonius turbine presents an attractive, environmentally friendly and cost effective electric generation in low velocity regions. However, this turbine has not been fully explored, as researchers are still searching for solution for the main problem of low efficiency of Savonius turbine configuration. This research paper proposes a novel system of ducted nozzle configuration around Savonius rotor to increase the efficiency of the turbine. In this study, six different duct nozzle designs had been investigated. A numerical investigation was carried out in this research work using finite volume Reynolds-Averaged Navier-Stokes Equations (RANSE) code ANSYS Fluent with Reynolds numbers of 1.32 × 10 5 . Consequently, validation was carried out following previous experiments. Flow characteristics through augmented configuration, and performance of the Savonius turbine had been studied, and it was found that the water flow speed had been enhanced by the developed ducted nozzle system. The maximum power coefficient of the ducted nozzle turbine was increased by 78% compared to the conventional modified rotor. The maximum power coefficient was 0.25 at tip speed ratio (TSR) of 0.73. The use of this system is expected to contribute towards a more efficient utilization of flows in rivers and channels for electrical generation in rural areas. [ABSTRACT FROM AUTHOR]

Micro hydrokinetic energy scheme presents an attractive, environmentally-friendly and efficient electric generation in rural, remote and hilly areas. However, this scheme is yet to be fully discovered, as researchers are still searching for solutions for the main problems of low velocity of current in the open flow channels and low efficiency of hydrokinetic turbines. This research proposes a novel system configuration to capture as much kinetic energy as possible from stream water current. This system, known as bidirectional diffuser augmented (BDA) channel, functions by utilizing dual directed nozzles in the flow and is surrounded by dual cross flow/Banki turbines. It is also important to obtain the efficient design parameters of the turbines to use in the current configuration. The appropriate angle is important in order to guide the flow to touch the blades more perpendicularly to capture as much torque and power as possible. Hence, experimental and numerical investigations have been carried out in this research paper to study the performance characteristics of the CFT configuration applied in BDA system and investigate the effects of blades' inlet and outlet angles of CFT runners on the internal flow characteristics and efficiency. In this study, four different runners with various inlet and outlet angles of two CFT have been investigated. The CFD results have been validated with the experimental work and proven acceptable with flow pattern and performance characteristics. The results of the current study conclude that the maximum power coefficients (Cp) of 0.612 and 0.473 for lower and upper turbines are recorded for best runner angles of Case 3. [ABSTRACT FROM AUTHOR]

Abstract: Several antidepressants have been used to treat severe pain in clinics. Recently, we reported that the centrally acting non-narcotic antitussive (cough suppressant drug), tipepidine produces an antidepressant-like effect in the forced swimming test, although the mechanism of action appears to be quite different from that of known antidepressants. In the present study, we investigated whether a combination of tipepidine and carbamazepine acts synergistically to induce an antinociceptive effect in the acetic acid-induced writhing test in mice. Prior to studying the combination of tipepidine and carbamazepine, the analgesic action of tipepidine alone was also examined in mice. Tipepidine at 5–40mg/kg i.p. significantly reduced the number of writhes induced by acetic acid in mice. Carbamazepine at 20mg/kg i.p. also significantly reduced the writhing reaction. Furthermore, co-administration of carbamazepine (5 and 10mg/kg, i.p.) and tipepidine (2.5mg/kg i.p.) significantly decreased the number of writhes induced by acetic acid. This finding suggests that a combination of carbamazepine and tipepidine may be a new strategy for the treatment of neuropathic pain such as what occurs in trigeminal neuralgia, because the use of carbamazepine is often limited by its adverse effects and by reduction of its analgesic efficacy by microsomal enzyme induction. [Copyright &y& Elsevier]