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This paper is addressing of a coupling Large-eddy simulation (LES) and RANS turbulence models with mixture fraction/probability density function as a combustion model. The two models have been implemented to simulate ethanol-air spray combustion. The gas phase is described with the Eulerian approach while the liquid phase is designed using a Lagrangian framework. The LES/PDF approach is obtained statistically. The sub-grid scale energy equation is used with the LES/PDF approach. The numerical results are validated with experimental data. Both LES/PDF and RANS/PDF approaches are compared with the experimental data. The LES/PDF approach shows a good agreement in predicting the average gas temperature compared with RANS/PDF approach. The LES/PDF shows a better prediction of both turbulence intensity profiles and the vortices which are generated in the turbulent flow in comparison with the RANS/PDF approach.

Despite the variability of Moroccan natural resources, few Moroccan natural fibers are exploited as natural textile composites. This study aims to investigate the characteristics of 3D warp interlo...

The production of free radicals is a major component of the oxidative stress that occurs in biological systems. This is linked to the development of various diseases, including diabetes and hypothyroidism. The presence of these free radicals can also affect the functioning of the antioxidant enzymes. Catalase is an important component of the antioxidant enzymes that protect cellular structures from the damage caused by free radicals. It also neutralizes the reactive oxygen species by preventing them from reacting with metal catalysts. The study was conducted to investigate the effects of Catalase on the activities of various antioxidants in people with diabetes and hypothyroidism. Depression of metabolism by hypothyroidism has been reported to decrease oxidant production and thus protect tissues against oxidant damage. The study included 120 subjects divided into four groups; the first group included 30 healthy control subjects, the second group includes 30 patient’s hypothyroidisms with type 2 DM, the third group included 30 patient’s hypothyroidisms only and the fourth group included 30 patients with type 2 DM only.

Actually, path planning is one of the most crucial aspects of mobile robots study. The primary goal of this research is to develop a solution to the path planning issues that occur when a “mobile robot” operates in a static environment. The problem is handled by finding a collision-free path that meets the given criteria for the shortest distance with quite the smoothness of the path. Two nature-inspired metaheuristic algorithms are used in the computation. By leading a hybrid “gray wolf optimization” with the “particle swarm optimization” (HGWO-PSO) computation that restricts the distance and follows path perfection guidelines, the primary shape is improved. In addition, simulation findings reveal that the proposed HGWOPSO method is deeply serious in terms of path optimality when compared to path planning approaches such as group search optimizer GSO, PSO, artificial bee colony ABC, and GWO.

In this paper, the genetic algorithm (GA) which is a stochastic optimization algorithm is proposed. The genetic algorithm is echoing the natural selection and genetics. The control of the suggested plant can be done in different ways. Genetics are used to solve the problem that will be in the system that is represented by the response, ripple, and overshoot. Here, the proportional, integral, and derivative (PID) controller is used. The Kp,,Ki , and Kd of PID are controlled using a genetic algorithm. Then the procedures of GA are given which are implemented in Matlab 2018a. Also, the output response is compared with the set value to check the ability of GA to get the optimal solution. Through simulated results, there is a high response to the system, as well as the ripple, and the overshoot decreased significantly compared to the conventional method in control.

Potholes represent one of the dangerous distress types on roads. They form as a result of various factors, including water ingress, freeze–thaw, and pavement condition deterioration. In the UK, 1.7 million potholes were repaired in 2021; this critical number causes significant economic, social, and environmental impacts; there is no tool able to predict the number of potholes that might appear in a road network. This study aims to analyze pothole formation and its relationship with other distress types and their severity, and to develop a simple tool able to predict the number of potholes that might appear in a road network based on the network condition. Significant pothole data from the road network of Greater London between 2017 and 2020, in addition to surface distress data, were used in this study. ‘Spatial density’ and ‘join’ tools embedded in ArcGIS were used to correlate pothole spatial density (PSD) with the road condition surrounding the potholes. This analysis was then used to calculate PSD as a function of different condition indicators, such as road condition index and crack intensity, allowing prediction of the number of potholes based on the length and condition of the sections being analyzed. The results demonstrate that potholes are significantly concentrated in sections with deteriorated conditions. They also show that it is possible to predict the number of potholes using PSD with reasonable accuracy. Lastly, it was found that sections with low crossfall are more susceptible to pothole formation, presumably because of water ponding and consequent damage.

The influence of masonry infills on the seismic response of reinforced concrete (RC) frame structures is evaluated based on comparative procedure between concentric and eccentric strut models. For this purpose, a four-story reinforced concrete frame structure was selected and designed according to Algerian seismic design code RPA 99/version2003. Comparisons were carried out with the variation in the mechanical characteristics of infills. To this end, three types of masonry infills were considered, defined as weak, intermediate and strong. A series of nonlinear dynamic analyses using a set of three time-history earthquake records were performed with the bare and regular infilled frames structural configurations. Results from nonlinear analyses furnish information on the interaction between the concentric/eccentric strut models and the surrounding structural elements, and their impact on the global and local responses. It is concluded that, at global level, the concentric strut model gives much stiffer response than the eccentric strut model and may be of some practical interest in the design of seismic gaps between adjacent structures; at local level, the concentric strut model is not able to reproduce the increasing of forces in columns due to infills and this increasing phenomenon is particularly relevant in the case of shear force for the strong masonry infill. This paper provides some limitations concerning the number of studied parameters; it can be extended through the consideration of wider set of parameters, such us infill thickness, number of stories, number of bays and irregular infill distribution, in particular soft first story.

Objectives The genus Ferulago belonging to the family Apiaceae is a flora widely distributed in Central Asia and the Mediterranean and used in folk medicine. It is administered as a sedative, tonic, digestive, aphrodisiac, also as a treatment for intestinal worms and haemorrhoids. Herein, we reported a review on phytochemistry and its biological activities reported from 1990 up to early 2020. All the information and reported studies concerning Ferulago plants were summarized from the library and digital databases (e.g. Scopus, Medline, Scielo, ScienceDirect, SciFinder and Google Scholar). Key findings The phytochemical investigations of Ferulago species revealed the presence of coumarins as the main bioactive compounds, including daucane derivatives, sesquiterpenes aryl esters, phenol derivatives, flavonoids and essential oils. Moreover, the therapeutic potentials of the pure compounds isolated from the genus Ferulago possess promising properties namely anticholinesterase, antimicrobial, anticoagulant, antileishmanial, antioxidant, antibacterial and antiproliferative. Summary Today, significant advances in phytochemical and biological activity studies of different Ferulago species have been revealed. The traditional uses and reported biological results could be correlated via the chemical characterization of these plants. All these data will support the biologists in the elucidation of the biological mechanisms of these plants.

Self-directed learning has proven to be advantageous for the students to conduct lifelong, satisfactory and independent learning while, problem-based learning is a constructive learning approach by enabling students to find solutions for the complex real-world problems. Aim of the study: The current study aimed to determine the relation between self-directed learning readiness and problem-based learning approach as perceived by nursing students. Design: A descriptive correlational research design was utilized. Sample: All target of nursing students (371) included in the studying in the second semester at all levels in the academic year 2017-2018 was recruited from the faculty of nursing in port-said university. Tools of data collection: Self-administered questionnaires scales were used to assess self-directed learning readiness and the problem-based learning approach as perceived by nursing students. Results: Students had moderate level of self-rating skills of self-directed learning, self-directed learning readiness, and low level of self-regulation responses (57.1%, 60.6%, 56.4% respectively) While, (50.4%) of students obtained low perception of problem-based learning approach. Conclusion: There was a positive statistically significant correlation (P≤0.001) between self-directed learning readiness and problem-based learning approach. Recommendations: Educational institutions in various fields must adopt the problem-based learning approach as a learning strategy and develop strategies to overcome obstacles that hinder application.

Objective: Nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of drugs widely used around the world for their analgesic, antipyretic and anti-inflammatory effect, but still have many limitations due to their side effects. So, these lead to the development of a new approach to search for a new product from natural plants that have similar therapeutic effects without common side effects like gastrointestinal ulcers. Method: The anti-inflammatory effect of β-amyrin palmitate (1) as triterpene and 1,7-bis (4- hydroxyphenyl) hept-4-en-3-one (2) as diarylheptanoid, isolated from Pellacalyx axillaris was studied by molecular docking to find the probability of binding position and binding strength of new compounds with particular Prostaglandin G/H synthase 2 (PDB ID: 1CX2). In vivo acute anti-inflammatory activity of the isolated compounds (1 and 2) was evaluated in rats using the egg-white induced edema model of inflammation in a dose correspondent to 3 mg/Kg of Diclofenac Sodium. Result: The tested isolated compounds showed a high activity to inhibit the swelling in paw edema and their anti-inflammatory effect began shortly after the injection of the egg white and continued to the end of the experiment in comparison to the reference and control. Conclusion: The isolated compounds show a long period of activity with a very potent effect, this may be related to their suitable acidity and may have perfect hydrophilic –lipophilic balance. This is the first study of anti-inflammatory effect using Paw edema model and molecular docking.

© 2020 Informa UK Limited, trading as Taylor & Francis Group. In asphalt mixture, a strong affinity between binder and aggregates is of prime importance, especially under conditions susceptible to moisture damage. Out of various modifiers/additives used in the literature, the hydrated lime (HL) has been reported as most suitable for improving affinity between binder and aggregates. Therefore, this study attempted to quantify the affinity of HL modified mastics with different aggregates under moist conditions. Further, in order to measure the affinity, the rolling bottle test (RBT) was used, which is also reported as one of the best empirical techniques for assessment of moisture susceptibility. However, in the RBT, the assessment for affinity is generally made through visual inspection by two experienced operators as per a standard procedure which can also be the major drawback of this technique in terms of less reliability and repeatability. Thereby, to reduce this deficiency, the image analysis (with no special setup) was also carried out through the use of the MATLAB program. The results as obtained from image analysis were then compared with the results of visual observation. Both were found to be very similar to each other. Hence, the RBT could be used confidently for the comparison of different binder/aggregate combinations. Also, the RBT results indicated that the HL addition was beneficial with granite, basalt and greywacke aggregates, but it did not have any effect with limestone aggregates. Further, the 10% HL substitution was found to be more efficient than 20% HL substitution as both substitutions showed a similar effect in most of the studied combinations.

The polydispersed nature of the spray is captured through the use of probability density functions based on the maximum entropy method to stand for the complete atomization characteristics of spray dynamics. The droplet and velocity size distributions are practical tools for the analysis of sprays cooling. The special benefit of the model is a Eulerian based which is less computationally intensive when compared to models that are based on the Lagrangian approach that tracks droplet parcel. The accuracy of using Lagrangian approach in polydispersed phase is always accurately less than Eulerian approach because it depends on the number of parcels while in Eulerian approach it depends on the proposed continuous distribution function. The main intent of the current work is to evaluate the capability of using the model for the initial predictions of the droplet size and velocity distribution for liquid nitrogen spray of solid-cone pressure swirl nozzle. The use of liquid injection pressure cases of up to 0.6MPa and spray cone angles of just 30◦ from three different sets of experimental data. The results being characterized are spray drop size distribution, liquid volume fraction and spray cone angle values. The unsteady analyses of the effect of injection pressure are studied on the cryogenic liquid nitrogen. The numerical results show that the maximum entropy method applies to liquid cryogenic spray and indicates that the model reacts correctly to changes in different injection pressures. Comparisons are also made with measured drop size distribution data that are reasonably captured and the spray cone angle is found to be in good agreement during initial and far-field spray angles.

In this letter, waking-up wireless sensors is achieved by solely relying on existing ambient radio frequency signals from commercial Wi-Fi routers. The wake-up is accomplished based on the captured Wi-Fi signal that is received by an antenna and then fed into a rectifier circuit. A novel packet injection algorithm is developed to enable the rectifier to efficiently convert the captured Wi-Fi signal into a dc power. This algorithm can be implemented on any commercial router with no modifications to the router's hardware or protocol stack and without compromising the performance of the Wi-Fi network. The design is experimentally validated under controlled conditions.

An experimental study was performed to evaluate the effect of the nano-fluid on the performance of the PV/Trombe wall system under the dry hot weathers. Nano-fluid (Al2O3/water) was used as a working medium of the heat exchanger of the PV/TW. Two concentration of the nano-particles (0.1% and 0.5%) were considered for various coolant flow rates and design configurations. It was recorded that the nano-fluid concentration of 0.5% yields the most significant reduction in the solar cell and the indoor space temperatures. Moreover, an increment in the produced electrical power and overall system efficiencies was recorded under the same conditions. The maximum reductions were 9 °C and 14.4 °C for the solar cell and the indoor space temperature, respectively. In addition, it was observed that the presence of the fan and increasing the volume flow rate of cooling fluid in the heat exchanger leads to increase the electrical and thermal efficiencies. The highest electrical and thermal efficiencies of the system were 9.2% and 62.99%, respectively, at the operational conditions (with Fan+ 300 L/day + Nano 0.5%). It can be concluded that the use of nano-fluids and increased flow of coolant in the heat exchanger is not a desirable option for indoor space heating.

Background: It is vital to increase nurses’ quality of work life because this has the potential both to improve organizational citizenship and ensure an adequate nursing work force. Aim: To explore the relationship between organizational citizenship behavior and quality of work life among nurses in Port Said hospitals. Subjects and Method: A descriptive comparative correlation research design was utilized. Setting: This study was conducted in General Port Said hospital and Atta Specialized hospital. Subjects: A sample of 207 nurses who at job in time of the study. Tools of data collection: Two tools included organizational citizenship behavior scale and quality of work life components. Results: Showed that, high percentage of studied nurses agreed on organizational citizenship behavior scale. It was determined that the nurses obtained the highest score from the altruism, conscientiousness dimension followed by courtesy. Regarding quality of work life components, it was found that around half and more of the studied person agreed on overall quality of work life. Conclusion:There was positive correlation among organizational citizenship behavior and dimensions of quality of work life. Recommendation: Increase training programs in hospitals help nurses to achieve the required skills and improve communication among nurses.

Wind energy is one of the cheapest sources of energy that may solve the Climate change problem and fresh water scarcity challenges. This article introduces a novel Desalination Wind Turbine that is cheaper and more efficient than the common wind turbine, especially offshore wind turbines. In this system, the wind energy transmitted to the water pump by a hydraulic transmission line. The RO module is used for fresh water production. The pressure recovery module is added to RO system, to increase the permeated flow. It can be increased the permeate flow up to 45%, which is significant. The Maximum Power Point Tracking (MPPT) based on the hydraulic oil pressure measurement is implemented. In addition, the Maximum Permeate Flow Tracking control loop, similar to MPPT, is introduced to optimized the pressure of the RO system. It is increased the annual permeate production up to 8%. The long term performance of the system, such as annual water production is calculated and the ability of the system to MPPT and the wind turbulence and gust is analyzed. The rotor speed overshoot of the closed loop system is less than 16%, which is acceptable.

El presente trabajo resalta la imagen del musulmán en la literatura española antes y después del siglo XIX, en este sentido hemos seleccionado algunas obras literarias como testimonios de la visión española hacia el hombre musulmán. Se puede notar obviamente en algunas obras el musulmán aparece como valiente y noble, mientras en otras aparece como cobarde y bárbaro según la tendencia y el grado del extremismo del autor. El presente estudio se trata de un estudio diacrónico cuya documentación ha sido repartida a dos etapas antes y después del siglo XIX: en cuanto a la etapa que precedió el siglo XIX hemos contado con obras como El Abencerraje, Las Guerras civiles de Granada, el Poema del Cid y las obras de Alfonso X, el Sabio mientras la segunda abarca algunas obras de escritores españoles como Manuel Fernández y Gonzáles, Pedro Antonio de Alarcón y Ramón Ortega y Frías.

The present study aims to delineate different types of the ground water accumulations in the northwest Gulf of Suez using geoelectrical and magnetic measurements. Twenty-one Vertical Electrical So...

To assess the diagnostic accuracy of haematoxylin-eosin staining in clinically suspected Hirschsprung disease, and to compare the findings with calretinin and S100 immunohistochemistry.The retrospective study was conducted at the AL-Khansaa Teaching Hospital, Nineveh, Iraq, and comprised data from January 2017 to October 2020 of rectal suction biopsies of patients with clinically and radiologically suspected Hirschsprung disease. Histopathology and immunohistochemistry were performed. Data was analysed using SPSS 16.Of the 114 patients, 74(64.9%) were males and 40(35.1%) were females. Based on histology, 28(24.6%) cases were negative for ganglion cells, and, of them 25(89.2%) revealed nerve bundle hypertrophy. The diagnostic accuracy for the detection of ganglion cell and nerve hypertrophy using haematoxylin-eosin stain was 99.1% and 94.4%, respectively. Correlation of haematoxylin-eosin staining with calretinin and S100 was statistically near perfection (κ= 0.976 and κ = 0.923), respectively.The mainstay to confirm or exclude Hirschsprung disease remains an accurate histopathological evaluation of the haematoxylin-eosin-stained sections of an adequate colorectal biopsy.

Joints in Roller Compacted Concrete (RCC) pavements are used to distribute traffic loading between adjacent slabs by friction. The Load Transfer Stiffness (LTS) of the joints has critical effects on RCC pavement performance near the joints. Research has shown that LTS can deteriorate over time due to traffic loading or environmental conditions. This study investigates the deterioration of LTS of RCC pavement joints and its effect on the fatigue cracking performance near the joints. To achieve that, first, an innovative experimental programme was designed to measure LTS as a function of number of load repetition, joint width, and RCC mix properties using a cyclic shear test setup. Second, a mathematical model was derived to predict LTS deterioration in joints. This model was validated against the experimental data. Lastly, an RCC pavement design model was developed using the LTS deterioration model. To demonstrate the application of the developed solution, a hypothetical RCC pavement structure consisting of four slabs was considered. The analysis results show that LTS has inverse relationship and direct impact of fatigue life of RCC. In particular, the results demonstrate that fatigue damage over an analysis period of 20 years is negligible if LTS is assumed constant, which is unrealistic, but it can reach 40% if LTS deterioration is considered in the analysis. Accordingly, this study recommends considering the deterioration of RCC joint LTS when design that kind of pavement structures. © 2022, The Author(s), under exclusive licence to Chinese Society of Pavement Engineering.

In order to provide constant DC voltage, buck converter is used which is a common converter in different applications. The use of artificial control methods for DC/DC converter will increase the productivity, spend low energy, and able to avoid the changes. Here, in order to control the proposed converter, intelligent regulation is utilized. Different methods have been suggested to satisfy the need of the output. The work uses proportional-integral-derivative (PID) controller which is received the error difference between the output and the desired. Fuzzy logic controller (FLC) is also used. While the fuzzy-PID supervised (FSC-PID) where the parameters of the PID is updated using the fuzzy system. The explanation of the proposed controllers is presented in this paper. PID, fuzzy logic controller, and fuzzy-PID supervised have been designed and implemented using MATLAB in order to settle the output of buck DC/DC converter. The complete system has been built in MATLAB/Simulink. The proposed controller keeps track the output to be exactly the set signal.