Search results for: Ahmed Abdel Malek

Authors: Salar Ahmed Ali

Abstract:

Hydraulic fracturing has revolutionized the extraction of unconventional oil and gas resources, significantly increasing global energy reserves. This paper explores recent advancements in hydraulic fracturing technologies, focusing on the integration of real-time monitoring systems, environmentally friendly fracturing fluids, and nanotechnology applications. Case studies demonstrate how innovative approaches have enhanced resource recovery while minimizing environmental impact and operational costs. Additionally, the paper addresses challenges such as induced seismicity and regulatory constraints, proposing solutions to ensure sustainable development. These advancements promise to make hydraulic fracturing more efficient, sustainable, and adaptable to the evolving energy landscape.

Keywords: oil, gas, fracture, hydraulic

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Authors: Ahmed Elmarhomy, K. Terada

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An automated method for counting passerby has been proposed using virtual-vertical measurement lines. Space-time image is representing the human regions which are treated using the segmentation process. Different color space has been used to perform the template matching. A proper template matching has been achieved to determine direction and speed of passing people. Distinguish one or two passersby has been investigated using a correlation between passerby speed and the human-pixel area. Finally, the effectiveness of the presented method has been experimentally verified.

Keywords: counting people, measurement line, space-time image, segmentation, template matching

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Authors: Shahin A. Abdel-Naby, Asad T. Hassan

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Astrophysical plasma environments can be classified into collisionally ionized (CP) and photoionizedplasmas (PP). In the PP, ionization is caused by an external radiation field, while it is caused by electron collision in the CP. Accurate and reliable laboratory astrophysical data for electron-ion recombination is needed for plasma modeling for low and high-temperatures. Dielectronic recombination (DR) is the dominant recombination process for the CP for most of the ions. When a free electron is captured by an ion with simultaneous excitation of its core, a doubly-exited intermediate state may be formed. The doubly excited state relaxes either by electron emission (autoionization) or by radiative decay (photon emission). DR process takes place when the relaxation occurs to a bound state by a photon emission. DR calculations at low-temperatures are problematic and challenging since small uncertaintiesin the low-energy DR resonance positions can produce huge uncertainties in DR rate coefficients.DR rate coefficients for N²⁺ and O³⁺ ions are calculated using state-of-the-art multi-configurationBreit-Pauli atomic structure AUTOSTRUCTURE collisional package within the generalized collisional-radiative framework. Level-resolved calculations for RR and DR rate coefficients from the ground and metastable initial states are produced in an intermediate coupling scheme associated withn = 0 and n = 1 core-excitations. DR cross sections for these ions are convoluted with the experimental electron-cooler temperatures to produce DR rate coefficients. Good agreements are foundbetween these rate coefficients and theexperimental measurements performed at CRYRING heavy-ionstorage ring for both ions.

Keywords: atomic data, atomic process, electron-ion collision, plasmas

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Authors: Asmaa Zaki M., Ahmed Abd El Aziz, Heba A. Fayed, Moustafa H. Aly

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ISLs are the most popular choice for deep space communications because these links are attractive alternatives to present day microwave links. This paper explored the allowable high data rate in this link over different orbits, which is affected by variation in modulation scheme and detector type. Moreover, the objective of this paper is to optimize and analyze the performance of ISL in terms of Q-factor and Minimum Bit Error Rate (Min-BER) based on different detectors comprising some parameters.

Keywords: free space optics (FSO), field of view (FOV), inter satellite link (ISL), optical wireless communication (OWC)

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Authors: Nada Mouchfiq, Ahmed Habbani, Chaimae Benjbara

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The security aspect of the IoT occupies a place of great importance especially after the evolution that has known this field lastly because it must take into account the transformations and the new applications .Blockchain is a new technology dedicated to the data sharing. However, this does not work the same way in the different systems with different operating principles. This article will discuss network security using the Blockchain to facilitate the sending of messages and information, enabling the use of new processes and enabling autonomous coordination of devices. To do this, we will discuss proposed solutions to ensure a high level of security in these networks in the work of other researchers. Finally, our article will propose a method of security more adapted to our needs as a team working in the ad hoc networks, this method is based on the principle of the Blockchain and that we named ”MPR Blockchain”.

Keywords: Ad hocs networks, blockchain, MPR, security

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Authors: Ahmad Alwosheel, Ahmed Alqaraawi

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This work proposes an unsupervised text-independent probabilistic approach to recognize Quran reciter voice. It is an accurate approach that works on real time applications. This approach does not require a prior information about reciter models. It has two phases, where in the training phase the reciters' acoustical features are modeled using Gaussian Mixture Models, while in the testing phase, unlabeled reciter's acoustical features are examined among GMM models. Using this approach, a high accuracy results are achieved with efficient computation time process.

Keywords: Quran, speaker recognition, reciter recognition, Gaussian Mixture Model

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Authors: Touila Ahmed, Elie Louis, Hamza Gharbi

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State of the art question answering models have recently shown impressive performance especially in a zero-shot setting. This approach is particularly useful when confronted with a highly diverse domain such as the legal field, in which it is increasingly difficult to have a dataset covering every notion and concept. In this work, we propose a flexible generative question answering approach to contract analysis as well as a weakly supervised procedure to leverage unannotated data and boost our models’ performance in general, and their zero-shot performance in particular.

Keywords: question answering, contract analysis, zero-shot, natural language processing, generative models, self-supervision

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Authors: Ahmed I. Osman, Jehad K. Abu-Dahrieh, Jillian M. Thompson, David W. Rooney

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Natural gas (the main constituent is Methane 95%) is considered as an alternative to petroleum for the production of synthetics fuels. Nowadays, methane combustion at low temperature has received much attention however; it is the most difficult hydrocarbon to be combusted. Co/Mo and (4:1 wt/wt) catalysts were prepared from a range of different precursors and used for the low temperature total methane oxidation (TMO). The catalysts were characterized by, XRD, BET and H2-TPR and tested under reaction temperatures of 250-400 °C with a GHSV= 36,000 mL g-1 h-1. It was found that the combustion temperature was dependent on the type of the precursor, and that those containing chloride led to catalysts with lower activity. The optimum catalyst was Co/Mo (4:1wt/wt) where greater than 20% methane conversion was observed at 250 °C. This catalyst showed a high degree of stability for TMO, showing no deactivation during 50 hours of time on stream.

Keywords: methane low temperature total oxidation, oxygen carrier, Co/Mo, Co/Mn

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Authors: Saadat Ali, Rashid Abdulla Ahmed Alshehhi

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Cable faults are always probable and common during or after commissioning, causing significant delays and disrupting power distribution or transmission network, which is intolerable for the utilities&service providers being their reliability and business continuity measures. Therefore, the adoption of rapid localization & rectification methodology is the main concern for them. This paper explores the present techniques available for high voltage cable localization & rectification and which is preferable with regards to easier, faster, and also less harmful to cables. It also provides insight experience of high resistance fault locating by utilization of the Very Low Frequency (VLF) method.

Keywords: faults, VLF, real cases, cables

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Authors: Ali Alhajeri, Tarig Makki, Mosa Almutahhar, Mohammed Ahmed, Usman Ali

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Metal powder is the raw material used for laser powder-bed fusion (LPBF) additive manufacturing (AM). There are many metal materials that can be used in LPBF. The properties of these materials are varied between each other, which can affect the building part. The objective of this paper is to do an overview of the titanium powders available in LBPF. Comparison between different literature works will lead us to study the similarities and differences between the powder properties such as size, shape, and chemical composition. Furthermore, the results of this paper will point out the significant titanium powder properties in order to clearly illustrate their effect on the build parts.

Keywords: LPBF, titanium, Ti-6Al-4V, Ti-5553, metal powder, AM

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Authors: Gehad S. Kaseb, Mona F. Ahmed

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Arabic Sentiment Analysis (SA) is one of the most common research fields with many open areas. Few studies apply SA to Arabic dialects. This paper proposes different pre-processing steps and a modified methodology to improve the accuracy using normal Support Vector Machine (SVM) classification. The paper works on two datasets, Arabic Sentiment Tweets Dataset (ASTD) and Extended Arabic Tweets Sentiment Dataset (Extended-AATSD), which are publicly available for academic use. The results show that the classification accuracy approaches 86%.

Keywords: Arabic, classification, sentiment analysis, tweets

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Authors: Fatima Faiza Ahmed, Syed Farrukh Hussain

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The last few decades have seen a large proportion of our population bending towards e-learning technologies, starting from learning tools used in primary and elementary schools to competency based e-learning systems specifically designed for applications like finance and marketing. The huge diversity in this crowd brings about a large number of challenges for the designers of these e-learning systems, one of which is the adaptability of such systems. This paper focuses on adaptability in the learning material in an e-learning course and how artificial intelligence and the semantic web can be used as an effective tool for this purpose. The study proved that the semantic web, still a hot topic in the area of computer science can prove to be a powerful tool in designing and implementing adaptable e-learning systems.

Keywords: adaptable e-learning, HTMLParser, information extraction, semantic web

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Authors: Ferhati Ahmed, Fillali Ahmed, Oulhadj Younsi

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delimitation of the perimeters of protection in the catchment area of the city of Adrar, which are established around the sites for the collection of water intended for human consumption of drinking water, with the objective of ensuring the preservation and reducing the risks of point and accidental pollution of the resource (Continental Intercalar groundwater of the Northern Sahara of Algeria). This wellfield is located in the northeast of the city of Adrar, it covers an area of 132.56 km2 with 21 Drinking Water Supply wells (DWS), pumping a total flow of approximately 13 Hm3/year. The choice of this wellfield is based on the favorable hydrodynamic characteristics and their location in relation to the agglomeration. The vulnerability to pollution of this slick is very high because the slick is free and suffers from the absence of a protective layer. In recent years, several factors have been introduced around the field that can affect the quality of this precious resource, including the presence of a strong centre for domestic waste and agricultural and industrial activities. Thus, its sustainability requires the implementation of protection perimeters. The objective of this study is to set up three protection perimeters: immediate, close and remote. The application of the Wyssling method makes it possible to calculate the transfer time (t) of a drop of groundwater located at any point in the aquifer up to the abstraction and thus to define isochrones which in turn delimit each type of perimeter, 40 days for the nearer and 100 days for the farther away. Special restrictions are imposed for all activities depending on the distance of the catchment. The application of this method to the Adrar city catchment field showed that the close and remote protection perimeters successively occupy areas of 51.14 km2 and 92.9 km2. Perimeters are delimited by geolocated markers, 40 and 46 markers successively. These results show that the areas defined as "near protection perimeter" are free from activities likely to present a risk to the quality of the water used. On the other hand, on the areas defined as "remote protection perimeter," there is some agricultural and industrial activities that may present an imminent risk. A rigorous control of these activities and the restriction of the type of products applied in industrial and agricultural is imperative.

Keywords: continental intercalaire, drinking water supply, groundwater, perimeter of protection, wyssling method

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Authors: Ahmed Jedidi, Mesfer Mohammed Alshamrani, Alwi Mohammad A. Bamhdi

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Optical performance monitoring and optical network management are essential in building a reliable, high-capacity, and service-differentiation enabled all-optical network. One of the serious problems in this network is the fact that optical crosstalk is additive, and thus the aggregate effect of crosstalk over a whole AON may be more nefarious than a single point of crosstalk. As results, we note a huge degradation of the Quality of Service (QoS) in our network. For that, it is necessary to identify and monitor the impairments in whole network. In this way, this paper presents new system to identify and monitor crosstalk in AONs in real-time fashion. particular, it proposes a new technique to manage intra-crosstalk in objective to relax QoS of the network.

Keywords: all-optical networks, optical crosstalk, optical cross-connect, crosstalk, monitoring crosstalk

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Authors: Hala Shaari, Nuredin Ahmed

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Teaching computer programming is recognized to be difficult and a real challenge. The biggest problem faced by novice programmers is their lack of understanding of basic programming concepts. A visualized learning tool was developed and used by volunteered first-year students for two semesters. The purposes of this paper are firstly, to emphasize factors which directly affect the performance of our students negatively. Secondly, to examine whether the proposed tool would improve their performance and learning progression. The results of adopting this tool were conducted using a pre-survey and post-survey questionnaire. As a result, students who used the learning tool showed better performance in their programming subject.

Keywords: factors, novice, programming, visualization

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Authors: Rowanda Daoud Ahmed, Mansoor Abdulhak, Muhammad Azeem Afzal, Sezer Filiz, Usama Ahmad Mughal

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This paper discusses important aspects of AI in the healthcare domain. The increase of data in healthcare both in size and complexity, opens more room for artificial intelligence applications. Our focus is to review the main AI methods within the scope of the health care domain. The results of the review show that recommendations for diagnosis and recommendations for treatment, patent engagement, and administrative tasks are the key applications of AI in healthcare. Understanding the potential of AI methods in the domain of healthcare would benefit healthcare practitioners and will improve patient outcomes.

Keywords: AI in healthcare, technologies of AI, neural network, future of AI in healthcare

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Authors: Ahmed Alqaoud

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This paper describes Publish/Subscribe Scientific Workflow Interoperability Framework (PS-SWIF) architecture and its components that collectively provide interoperability between heterogeneous scientific workflow systems. Requirements to achieve interoperability are identified. This paper also provides a detailed investigation and design of models and solutions for system requirements, and considers how workflow interoperability models provided by Workflow Management Coalition (WfMC) can be achieved using the PS-SWIF system.

Keywords: publish/subscribe, scientific workflow, web services, workflow interoperability

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Authors: Fatima Zohra Zeggai, Benjamin Carbonnier, Aïcha Hachemaoui, Ahmed Yahiaoui, Samia Mahouche-Chergui, Zakaria Salmi

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A series of polyaniline (PANI)/modified Montmorillonite (MMT) Clay nanocomposite materials have been successfully prepared by In-Situ polymerization in the presence of modified MMT-Clay or Diazonium-MMT-Clay. The obtained nanocomposites were characterized and compared by various physicochemical techniques. The presence of physicochemical interaction, probably hydrogen bonding, between clay and polyaniline, which was confirmed by FTIR, UV-Vis Spectroscopy. The electrical conductivity of neat PANI and a series of the obtained nanocomposites were also studied by cyclic voltammograms.

Keywords: polyaniline, clay, nanocomposites, in-situ polymerization, polymers conductors, diazonium salt

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Authors: Ahmed R. Abdelaziz, Zaki M. I. Osha

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Solar radiation data are of great significance for solar energy system design. This study aims at developing and calibrating new empirical models for estimating monthly mean daily global solar radiation on a horizontal surface in Alexandria, Egypt. Day length hours, sun height, day number, and declination angle calculated data are used for this purpose. A comparison between measured and calculated values of solar radiation is carried out. It is shown that all the proposed correlations are able to predict the global solar radiation with excellent accuracy in Alexandria.

Keywords: solar energy, global solar radiation, model, regression coefficient

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Authors: M. A. Abdel-Wahed, Nayera Elmorsi Hassan, Safaa Shafik Imam, Ola G. El-Farghali, Khadija M. Alian

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Low-birth-weight is a challenging public health problem. Aim: to clarify role of zinc on enhancing catch-up growth of low-birth-weight and find out a proposed relationship between zinc effect on growth and the main growth hormone mediator, IGF-1. Methods: Study is a double-blind-randomized-placebo-controlled trial conducted on low-birth-weight-neonates delivered at Ain Shams University Maternity Hospital. It comprised 200 Low-birth-weight-neonates selected from those admitted to NICU. Neonates were randomly allocated into one of the following two groups: group I: low-birth-weight; AGA or SGA on oral zinc therapy at dose of 10 mg/day; group II: Low-birth-weight; AGA or SGA on placebo. Anthropometric measurements were taken including birth weight, length; head, waist, chest, mid-upper arm circumferences, triceps and sub-scapular skin-fold thicknesses. Results: At 12-month-old follow-up visit, mean weight, length; head (HC), waist, chest, mid-upper arm circumferences and triceps; also, infant’s proportions had values ≥ 10th percentile for weight, length and HC were significantly higher among infants of group I when compared to those of group II. Oral zinc therapy was associated with 24.88%, 25.98% and 19.6% higher proportion of values ≥ 10th percentile regarding weight, length and HC at 12-month-old visit, respectively [NNT = 4, 4 and 5, respectively]. Median IGF-1 levels measured at 6 months were significantly higher in group I compared to group II (median (range): 90 (19 – 130) ng/ml vs. 74 (21 – 130) ng/ml, respectively, p=0.023). Conclusion: Oral zinc therapy in low-birth-weight neonates was associated with significantly more catch-up growth at 12-months-old and significantly higher serum IGF-1 at 6-month-old.

Keywords: low-birth-weight, zinc, catch-up growth, neonates

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Authors: Rawaa Maher, Ahmed Allam, Haruichi Kanaya, Adel B. Abdelrahman

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In this paper, a compact, high-efficiency integrated rectenna is presented to operate in the 2.45 GHz band. A comparison between two rectifier topologies is performed to verify the benefits of removing the matching network from the rectifier. A rectifier high conversion efficiency of 74.1% is achieved. To complete the rectenna system, a novel omnidirectional antenna with high gain (3.72 dB) and compact size (25 mm * 29 mm) is designed and fabricated. The same antenna is used with a reflector for raising the gain to nearly 8.3 dB. The simulation and measurement results of the antenna are in good agreement.

Keywords: internet of things, integrated rectenna, rectenna, RF energy harvesting, wireless sensor networks(WSN)

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Authors: Ahmed Hamza Yache

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The main purpose of this study is to estimate the distribution of shear forces in building structures with asymmetries in the plan submitted to seismic forces can cause, in this case, simultaneous deformations of translation and torsion. To this end, the distribution of shear forces is obtained by seismic forces calculated from the equivalent static method of the Algerian earthquake code RPA 99 (2003 version) and spectral modal analysis for an irregular building plan without kinks. Comparison of the results obtained by these two methods used to highlight the difference in terms of distributions of shear forces in such structures.

Keywords: structure, irregular, code, seismic, method, force, period

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Authors: Mohamed Malek Khenissi, Mohamed Montassar Ben Slama, Anis Belhaj Mohamed, Moncef Saidi

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Northern Tunisia is well known by its different and complex structural and geological zones that have been the result of a geodynamic history that extends from the early Mesozoic era to the actual period. One of these zones is the salt province, where the Halokinesis process is manifested by a number of NE/SW salt structures such as Jebel Ech-Cheid which represents masses of materials characterized by a high plasticity and low density. The salt masses extrusions that have been developed due to an extension that started from the late Triassic to late Cretaceous. The evolution of salt bodies within sedimentary basins have not only contributed to modify the architecture of the basin, but it also has certain geochemical effects which touch mainly source rocks that surround it. It has been demonstrated that the presence of salt structures within sedimentary basins can influence its temperature distribution and thermal history. Moreover, it has been creating heat flux anomalies that may affect the maturity of organic matter and the timing of hydrocarbon generation. Field samples of the Bahloul source rock (Cenomanan-Tunonian) were collected from different sights from all around Ech Cheid salt structure and evaluated using Rock-eval pyrolysis and GC/MS techniques in order to assess the degree of maturity evolution and the heat flux anomalies in the different zones analyze. The Total organic Carbon (TOC) values range between 1 to 9% and the (Tmax) ranges between 424 and 445°C, also the distribution of the source rock biomarkers both saturated and aromatic changes in a regular fashions with increasing maturity and this are shown in the chromatography results such as Ts/(Ts+Tm) ratios, 22S/(22S+22R) values for C31 homohopanes, ββ/(ββ+αα)20R and 20S/(20S+20R) ratios for C29 steranes which gives a consistent maturity indications and assessment of the field samples. These analyses are carried to interpret the maturity evolution and the heat flux around Ech Cheid salt structure through the geological history. These analyses also aim to demonstrate that the salt structure can have a direct effect on the geothermal gradient of the basin and on the maturity of the Bahloul Formation source rock. The organic matter has reached different stages of thermal maturity, but delineate a general increasing maturity trend. Our study confirms that the J. Ech Cheid salt body have on the first hand: a huge influence on the local distribution of anoxic depocentre at least within Cenomanian-Turonian time. In the second hand, the thermal anomaly near the salt mass has affected the maturity of Bahloul Formation.

Keywords: Bahloul formation, depocentre, GC/MS, rock-eval

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Authors: Safiah Ahmed Yahya Madkhali

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The aim of the present paper is to provide a characterization of the expression of comparison in the language of the Qur’an, the language of the Divine Book of the Muslim nation. It focuses on quantitative as well as qualitative comparisons. While works on comparison constructions in Arabic focus on a type(s) of the comparison construction and exclude another and investigate its behaviour in Standard Arabic, the paper aims to be inclusive of the varied instances that are scalar comparison constructions and describe its aspects in the language of the Qur’an. To the best of my knowledge, comparative constructions in the language of the Qur’an has not been tackled before and hence the characterization provided in the paper would be the contribution of the present work. The paper highlights the several rhetorical features of the construction as present in the different verses in the Qur’an which set them distinct from the ordinary use of the construction in the different verities of the Arabic language.

Keywords: comparison constructions, inequality, comparative, superlative, equality

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Authors: Dina Magdy Abdo, Ayat N. El-Shazly, E. A. Abdel-Aal

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Forward osmosis (FO) is one of the important processes during the wastewater treatment system for environmental remediation and fresh water regeneration. Both Egypt and China are troubled by over millions of tons of wastewater every year, including domestic and industrial wastewater. However, the traditional FO process in wastewater treatment usually suffers low efficiency and high energy consumption because of the continuously diluted draw solution. An additional concentration process is necessary to keep running of FO separation, causing energy waste. Based on the previous study on photothermal membrane, a sun-driven evaporation process is integrated into the draw solution side of FO system. During the sun-driven evaporation, not only the draw solution can be concentrated to maintain a stable and sustainable FO system, but fresh water can be directly separated for regeneration. Solar energy is the ultimate energy source of everything we have on Earth and is, without any doubt, the most renewable and sustainable energy source available to us. Additionally, the FO membrane process is rationally designed to limit the concentration polarization and fouling. The FO membrane’s structure and surface property will be further optimized by the adjustment of doping ratio of controllable nano-materials, membrane formation conditions, and selection of functional groups. A novel kind of nano-composite functional separation membrane with bi-interception layers and high hydrophilicity will be developed for the application in wastewater treatment. So, herein we aim to design a new wastewater treatment system include forward osmosis with high-efficiency energy recovery via the integration of photothermal membrane.

Keywords: forward osmosis, membrane, solar, water treatement

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Authors: S. Reaz Ahmed, M. S. Kaiser

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The tribological behavior of commercially used Perspex was evaluated under dry and wet sliding condition using a pin-on-disc wear tester with different applied loads ranging from 2.5 to 20 N. Experiments were conducted with varying sliding distance from 0.2 km to 4.6 km, wherein the sliding velocity was kept constant, 0.64 ms^-1. The results reveal that the weight loss increases with applied load and the sliding distance. The nature of the wear rate was very similar in both the sliding environments in which initially the wear rate increased very rapidly with increasing sliding distance and then progressed to a slower rate. Moreover, the wear rate in wet sliding environment was significantly lower than that under dry sliding condition. The worn surfaces were characterized by optical microscope and SEM. It is found that surface modification has significant effect on sliding wear performance of Perspex.

Keywords: Perspex, wear, friction, SEM

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Authors: Karima Menad, Ahmed Feddag

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In this study, large crystals of the zeolite NaA were synthesized by hydrothermal way. By following this zeolite was used to recover two heavy metals that are allowing the most dangerous toxic, lead and cadmium. The synthesized zeolite was analyzed by XRD and SEM aims to verify its purity and its good morphology; after it was undergoing ion exchange operations by aqueous solution with lead and cadmium in two salts Pb(CH3COOH)2 and CdCl2 at different concentrations. The exchange was carried out under the effect of two temperatures (25 °C and 60 °C). The contents of Pb++, Cd++ and Na+ were analyzed by atomic absorption and the results are given in the form of exchange rates. At the end the samples are analyzed by XRD exchanged to confirm their conservation of their zeolite framework. It is found that the exchange rate increases with the increase of initial concentration and the best results are found for the temperature of 60 °C.

Keywords: exchange rate, ion exchange, LTA zeolite, zeolite NaA

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Authors: Karim S. Hassan, Hisham M. Hamed, Yassmine A. Fahmy, Ahmed F. Shalash

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The mismatch between in-phase and quadrature signals in Orthogonal frequency division multiplexing (OFDM) systems, such as DVB-T2, results in a severe degradation in performance. Several general solutions have been proposed in the past, but these are largely computationally intensive, leading to complex implementations. In this paper, we propose a relatively simple iterative solution, which provides good results in relatively few iterations, using fixed precision arithmetic. An additional advantage is that complex digital blocks, such as dividers and square root, are not required. Thus, the proposed solution may be implemented in relatively simple hardware.

Keywords: OFDM, DVB-T2, I/Q imbalance, I/Q mismatch, iterative method, fixed point, reduced complexity

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Authors: Fatma Abdel Moneim Al Tawil

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This study was undertaken to evaluate an educational program regarding scientific writing and presentation skills among university students. This interventional study used a one-group, pretest/posttest design and was conducted in Al Jouf University among four colleges in Saudi Arabia. Baseline students’ assessment was conducted for developing educational program. Interventional, one group, pretest/posttest study was designed to evaluate the effectiveness of the educational program. Three parts evaluation sheet with total scores of 30 was used for 113 students for the development of the program and 52 students for test pretest phase. Wilcoxon signed ranks showed statistically significant improvement in the combined overall program skills score from a median of 56.7 pre to a median of 86.7 post, (z = 6.231, p < 0.001). When compared to preprogram intervention, post interventions 51.9 % of students achieve excellent performance. While pre intervention no students (0.0 %) achieve this score. Regarding to scientific writing skills, Wilcoxon signed ranks showed statistically significant improvement in the score from a median of 60 pre to a median of 90 post, (z = 6.122, p < 0.001). None of students had excellent performance changed to 73.1%. Regarding to oral presentation skills, Wilcoxon signed ranks showed statistically significant improvement in the score from a median of 50 pre to a median of 80 post, (z = 6.153, p < 0.001). None of students had excellent performance changed to 48.1%. Such educational program needs to be incorporated into classroom delivery of the students’ curriculum. Scientific writing skills book needed to be developed to be recommended as a basic educational strategy for all university faculties.

Keywords: scientific writing, presentation skills, university students, educational program

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Authors: Fatiha Boudjema, Samia Boudergua, Abdallah Elhirtsi Nour El Houda, Ahmed Mbarek Kaouther

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The main objective of our work is to prepare and characterize a moisturizing lip balm based on natural ingredients such as waxes, vegetable oils, and shea butter. First, the vegetable and essential oils were extracted, and then lip balm was prepared. The extracted oils and the lip balm were submitted to many tests in order to guarantee their quality and effectiveness. These tests show that our balm has a shear thinning behavior with a melting point of 58 °C and that it spreads easily on the skin without showing an allergic reaction. The balm showed a moisturising effect and stability over the two-month period at storage room temperature condition.

Keywords: lip balm, natural products, rheological study, antioxydant activity

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