Search results for: Sidi Ahmed Maouloud
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1583

Search results for: Sidi Ahmed Maouloud

1463 Effect of Atrial Flutter on Alcoholic Cardiomyopathy

Authors: Ibrahim Ahmed, Richard Amoateng, Akhil Jain, Mohamed Ahmed

Abstract:

Alcoholic cardiomyopathy (ACM) is a type of acquired cardiomyopathy caused by chronic alcohol consumption. Frequently ACM is associated with arrhythmias such as atrial flutter. Our aim was to characterize the patient demographics and investigate the effect of atrial flutter (AF) on ACM. This was a retrospective cohort study using the Nationwide Inpatient Sample database to identify admissions in adults with principal and secondary diagnoses of alcoholic cardiomyopathy and atrial flutter from 2019. Multivariate linear and logistic regression models were adjusted for age, gender, race, household income, insurance status, Elixhauser comorbidity score, hospital location, bed size, and teaching status. The primary outcome was all-cause mortality, and secondary outcomes were the length of stay (LOS) and total charge in USD. There was a total of 21,855 admissions with alcoholic cardiomyopathy, of which 1,635 had atrial flutter (AF-ACM). Compared to Non-AF-ACM cohort, AF-ACM cohort had fewer females (4.89% vs 14.54%, p<0.001), were older (58.66 vs 56.13 years, p<0.001), fewer Native Americans (0.61% vs2.67%, p<0.01), had fewer smaller (19.27% vs 22.45%, p<0.01) & medium-sized hospitals (23.24% vs28.98%, p<0.01), but more large-sized hospitals (57.49% vs 48.57%, p<0.01), more Medicare (40.37% vs 34.08%, p<0.05) and fewer Medicaid insured (23.55% vs 33.70%, p=<0.001), fewer hypertension (10.7% vs 15.01%, p<0.05), and more obesity (24.77% vs 16.35%, p<0.001). Compared to Non-AF-ACM cohort, there was no difference in AF-ACM cohort mortality rate (6.13% vs 4.20%, p=0.0998), unadjusted mortality OR 1.49 (95% CI 0.92-2.40, p=0.102), adjusted mortality OR 1.36 (95% CI 0.83-2.24, p=0.221), but there was a difference in LOS 1.23 days (95% CI 0.34-2.13, p<0.01), total charge $28,860.30 (95% CI 11,883.96-45,836.60, p<0.01). In patients admitted with ACM, the presence of AF was not associated with a higher all-cause mortality rate or odds of all-cause mortality; however, it was associated with 1.23 days increase in LOS and a $28,860.30 increase in total hospitalization charge. Native Americans, older age and obesity were risk factors for the presence of AF in ACM.

Keywords: alcoholic cardiomyopathy, atrial flutter, cardiomyopathy, arrhythmia

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1462 Effect of Knowledge of Bubble Point Pressure on Estimating PVT Properties from Correlations

Authors: Ahmed El-Banbi, Ahmed El-Maraghi

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PVT properties are needed as input data in all reservoir, production, and surface facilities engineering calculations. In the absence of PVT reports on valid reservoir fluid samples, engineers rely on PVT correlations to generate the required PVT data. The accuracy of PVT correlations varies, and no correlation group has been found to provide accurate results for all oil types. The effect of inaccurate PVT data can be significant in engineering calculations and is well documented in the literature. Bubble point pressure can sometimes be obtained from external sources. In this paper, we show how to utilize the known bubble point pressure to improve the accuracy of calculated PVT properties from correlations. We conducted a systematic study using around 250 reservoir oil samples to quantify the effect of pre-knowledge of bubble point pressure. The samples spanned a wide range of oils, from very volatile oils to black oils and all the way to low-GOR oils. A method for shifting both undersaturated and saturated sections of the PVT properties curves to the correct bubble point is explained. Seven PVT correlation families were used in this study. All PVT properties (e.g., solution gas-oil ratio, formation volume factor, density, viscosity, and compressibility) were calculated using the correct bubble point pressure and the correlation estimated bubble point pressure. Comparisons between the calculated PVT properties and actual laboratory-measured values were made. It was found that pre-knowledge of bubble point pressure and using the shifting technique presented in the paper improved the correlation-estimated values by 10% to more than 30%. The most improvement was seen in the solution gas-oil ratio and formation volume factor.

Keywords: PVT data, PVT properties, PVT correlations, bubble point pressure

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1461 The Paleoenvironment and Paleoclimatological Variations during Aptian in North Central Tunisia

Authors: Houda Khaled, Frederic Boulvain, Fredj Chaabani

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This paper focuses on the sedimentological and mineralogical studies of Aptian series outcrops in the Serdj and Bellouta Mountain situated in north-central Tunisia. In the Serdj Mountain, the Aptian series is about 590 meters thick and it is defined by tow formations corresponding respectively to the Sidi Hamada formation (Barremian-Gragasian) and the Serdj formation (Middle Gragasian-Late Clansaysian). This later is consisting of five limestones sequences separated by marly levels limestones associated to some siltstones bed. The Bellouta section is especially composed of carbonate rocks and it is attributed to the Middle Gragasian - Late Clansaysian. These sections are studied in detail regarding lithology, micropaleontology, microfacies, magnetic susceptibility and mineralogical composition in order to provide new insights into the paleoenvironmental evolution and paleoclimatological implications during Aptian. The following facies associations representing different ramp palaeoenvironments have been identified: mudstone-wackestone outer ramp facies; skeletal grainstone-packstone mid-ramp facies, packstone-grainstone inner-ramp facies which include a variety of organisms such as ooliths, rudists ostracods associated to athor bioclats. The coastal facies is especially defined by a mudstone -wackestone texture coastal rich with miliolidea and orbitolines. The magnetic susceptibility (Xin) of all samples was compared with the lithological and microfacies variation. The MS curves show that the high values are correlated with the distal facies and the low values are registred in the coastal environment. The X-ray diffractometer analysis show the presence of kaolinite and illite.

Keywords: Aptian, Serdj formation, mineralogy, petrography

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1460 Application of Numerical Modeling and Field Investigations for Groundwater Recharge Characterization at Abydos Archeological Site, Sohag, Egypt

Authors: Sherif A. Abu El-Magd, Ahmed M. Sefelnasr, Ahmed M. Masoud

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Groundwater modeling is the way and tool for assessing and managing groundwater resources efficiently. The present work was carried out in the ancient Egyptian archeological site (Abydos) fromDynastyIandII.Theareaislocated about 13km west of the River Nilecourse, Upper Egypt. The main problem in this context is that the ground water level rise threatens and damages fragile carvings and paintings of the ancient buildings. The main objective of the present work is to identify the sources of the groundwater recharge in the site, further more, equally important there is to control the ground water level rise. Numerical modeling combined with field water level measurements was implemented to understand the ground water recharge sources. However, building a conceptual model was an important step in the groundwater modeling to phase to satisfy the modeling objectives. Therefore, boreholes, crosssections, and a high-resolution digital elevation model were used to construct the conceptual model. To understand the hydrological system in the site, the model was run under both steady state and transient conditions. Then, the model was calibrated agains the observation of the water level measurements. Finally, the results based on the modeling indicated that the groundwater recharge is originating from an indirect flow path mainly from the southeast. Besides, there is a hydraulic connection between the surface water and groundwater in the study site. The decision-makers and archeologyists could consider the present work to understand the behavior of groundwater recharge and water table level rise.

Keywords: numerical modeling, archeological site, groundwater recharge, egypt

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1459 Early versus Late Percutaneous Tracheostomy in Critically Ill Adult Mechanically Ventilated Patients

Authors: Kamel Abd Elaziz Mohamed, Ahmed Yehia Mousa, Ahmed Samir ElSawy, Adel Mohamed Saleem

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Introduction: Critically ill patients frequently require tracheostomy to simplify long term air way management. While tracheostomy indications have remained unchanged, the timing of elective tracheostomy for the ventilated patient has been questioned. Aim of the work: This study was performed to compare the differences between early and late percutaneous dilatational tracheostomy (PDT) regarding, mechanical ventilation duration (MVD), length of ICU stay, length of hospital stay, incidence of ventilator associated pneumonia and hospital outcome. Patients and methods: Forty patients who met the inclusion criteria were randomly divided into early PDT who had the tracheostomy within the first 10 days of mechanical ventilation (MV) and the late PDT who had the tracheostomy after 10 days of MV. On admission, demographic data and Acute Physiology and Chronic ill Health II and GCS were collected. The duration of mechanical ventilation, ICU length of stay (LOS) and hospital LOS were all calculated. Results: Total of 40 patients were randomized to either early PDT (n= 20) or late PDT (n= 20). There were no significant differences between both groups regarding demographic data or the scores: APACHE II (22.75± 7 vs 24.35 ± 8) and GCS (6.10 ±2 vs 7.10 ± 2.71). An early PDT showed fewer complications vs late procedure, however it was insignificant. There were significant differences between the two groups regarding mean (MVD) which was shorter in early PDT than the late PDT group (32.2± 10.5) vs (20.6 ± 13 days; p= 0.004). Mean ICU stay was shorter in early PDT than late PDT (21 .0± 513.4) vs (40.15 ±12.7 days; p 6 0.001). Mean hospital stay was shorter in early PDT than late PDT (34.60± 18.37) vs (55.60± 25.73 days; p=0.005). Patients with early PDT suffered less sepsis and VAP than late PDT, there was no difference regarding the mortality rate between the two groups. Conclusion: Early PDT is recommended for patients who require prolonged tracheal intubation in the ICU as outcomes like the duration of mechanical ventilation length of ICU stay and hospital stay were significantly shorter in early tracheostomy.

Keywords: intensive care unit, early PDT, late PDT, intubation

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1458 Ulnar Parametacarpal Flap for Coverage of Fifth Finger Defects: Propeller Flap Concept

Authors: Ahmed M. Gad, Ahmed S. Hweidi

Abstract:

Background: Defects of the little finger and adjacent areas are not uncommon. It could be a traumatic, post-burn, or after contracture release. Different options could be used for resurfacing these defect, including skin grafts, local or regional flaps. Ulnar para-metacarpal flap described by Bakhach in 1995 based on the distal division of the dorsal branch of the ulnar artery considered a good option for that. In this work, we applied the concept of propeller flap for better mobilization and in-setting of the ulnar para-metacarpal flap. Methods: The study included 15 cases with 4 females and 11 male patients. 10 of the patients had severe post-burn contractures of little finger, and 5 had post-traumatic little finger defects. Contractures were released and resulting soft tissue defects were reconstructed with propeller ulnar para-metacarpal artery flap. The flap based on two main perforators communicating with the palmar system, it was raised based on one of them depending on the extent of the defect and rotated 180 degrees after judicious dissection of the perforator. Results: 13 flaps survived completely, one of the cases developed partial skin loss, which healed by dressing, another flap was completely lost and covered later by a full-thickness skin graft. Conclusion: Ulnar para-metacarpal flap is a reliable option to resurface the little finger as well as adjacent areas. The application of the propeller flap concept based on whether the proximal or distal communicating branch makes the rotation and in-setting of the flap easier.

Keywords: little finger defects, propeller flap, regional hand defects, ulnar parametacarpal flap

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1457 Effect of Ethanol and Betadine on the Preformed Biofilm of Staphylococcus Aureus Isolated from Urinary Catheter

Authors: Kara Terki Ibtissem, Hassaine Hafida, Bellifa Samia

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Introduction: Staphylococcus aureus is one of the species that are most frequently isolated from urinary catheters. The ability to produce a biofilm is an important step in the pathogenesis of these staphylococci; biofilm formation is strongly dependent on the environmental conditions it also depends on the different parameters these biofilms are subjected to. Antiseptics, including ethanol and betadine, are used in clinical practice for disinfection and infection prevention. Recent studies, however, demonstrate that disinfectants may enhance biofilm production in Staphylococci. Methods: In this study, 48 staphylococcus aureus isolated from urinary catheters at the University Hospital Center of Sidi Bel Abbes (in Northwestern Algeria) were analyzed to detect the formation of biofilm by culture on Red Congo Agar (RCA), the Tube Method (TM) and tissue Culture Plate (TCP) techniques, this last was also used to investigate the effect of ethanol and Betadine on the preformed biofilm In a second time to know which environment is most favorable to the formation of the biofilm we perform a statistical test based on the student test by the software R. Results: It has been found that 23 strains produced a bacterial slime on the Congo red medium, 5 strains produced a biofilm by the tube method, 2 of which are highly productive. In addition, 7 strains produced a biofilm on polystyrene micro-plates; this number was higher in the presence of ethanol 70% and ethanol 90% with 19 and 11 biofilm-producing strains, respectively. On the other hand, no biofilm was formed in the presence of Betadine. Conclusion: It is important to examine the response of biofilms following an imposed external constraint, such as disinfectants, in order to develop new strategies to combat bacterial biofilms but also to better control their formation.

Keywords: staphylococcus aureus, biofilm, urinary catheter, ethanol

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1456 Determination of the Water Needs of Some Crops Irrigated with Treated Water from the Sidi Khouiled Wastewater Treatment Plant in Ouargla, Algeria

Authors: Dalila Oulhaci, Mehdi Benlarbi, Mohammed Zahaf

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The irrigation method is fundamental for maintaining a wet bulb around the roots of the crop. This is the case with localized irrigation, where soil moisture can be maintained permanently around the root system between the two water content extremes. Also, one of the oldest methods used since Roman times throughout North Africa and the Near East is based on the frequent dumping of water into porous pottery vases buried in the ground. In this context, these two techniques have been combined by replacing the pottery vase with plastic bottles filled with sand that discharge water through their perforated walls into the surrounding soil. The first objective of this work is the theoretical determination using CLIMWAT and CROPWAT software of the irrigation doses of some crops (palm, wheat, and onion) and experimental by measuring the humidity of the soil before and after watering. The second objective is to determine the purifying power of the sand filter in the bottle. Based on the CROPWAT software results, the date palm needs 18.5 mm in the third decade of December, 57.2 mm in January, and 73.7 mm in February, whereas the doses received by experimentally determined by means of soil moisture before and after irrigation are 19.5 mm respectively, 79.66 mm and 95.66 mm. The onion needs 14.3 mm in the third decade of December of, 59.1 mm in January, and 80 mm in February, whereas the experimental dose received is 15.07 mm, respectively, 64.54 and 86.8 mm. The total requirements for the vegetative period are estimated at 1642.6 mm for date palms, 277.4 mm for wheat, and 193.5 mm for onions. The removal rate of the majority of pollutants from the bottle is 80%. This work covers, on the one hand, the context of water conservation, sustainable development, and protection of the environment, and on the other, the agricultural field.

Keywords: irrigation, sand, filter, humidity, bottle

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1455 Awareness of Drug Interactions among Physicians at Governmental Health Centers in Bahrain

Authors: Yasin I. Tayem, Jamil Ahmed, Mahmood Bahzad, Abdullah Alnama, Fahad Al Asfoor, Mahmood A. Jalil, Mohammed Radhi, Ahmed Alenezi, Khalid A. J. Al-Khaja

Abstract:

Drug-drug interactions (DDIs) represent a significant cause of patient’s morbidity and mortality. The rate of DDIs is rapidly increasing worldwide with the increasing proportion of ageing population and frequent requirement of polypharmacy-prescription of multiple drugs to treat comorbidities. Prescribing physicians are responsible for checking their prescriptions for the presence and severity of DDIs. However, since a large number of new drugs are approved and marketed every year, new interactions between medications are increasingly reported. Consequently, it is no longer practical for physicians to rely only upon their previous knowledge of medicine to avoid potential DDIs. The aim of this study was to explore the perceptions of physicians working at primary healthcare centers in Bahrain towards DDIs and how they manage them during their practice. Methodology: In this cross-sectional study, physicians working at all governmental primary healthcare centers in Bahrain were invited to voluntarily, privately and anonymously respond to a self-administered questionnaire. The questionnaire aims to assess their self-reported knowledge of DDIs and how they check for them in their practice. The participants were requested to provide socio demographic data and information related to their attitudes towards DDIs including strategies they employ for detecting and managing them, and their awareness of drugs which commonly cause DDIs. At the end of the questionnaire, an open-ended item was added to allow participants to further add any comment. Findings and Conclusions: The study is going on currently, and the results and conclusions will be presented at the conference.

Keywords: awareness, drug interactions, health centres, physicians

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1454 Upgrading of Problem-Based Learning with Educational Multimedia to the Undergraduate Students

Authors: Sharifa Alduraibi, Abir El Sadik, Ahmed Elzainy, Alaa Alduraibi, Ahmed Alsolai

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Introduction: Problem-based learning (PBL) is an active student-centered educational modality, influenced by the students' interest that required continuous motivation to improve their engagement. The new era of professional information technology facilitated the utilization of educational multimedia, such as videos, soundtracks, and photographs promoting students' learning. The aim of the present study was to introduce multimedia-enriched PBL scenarios for the first time in college of medicine, Qassim University, as an incentive for better students' engagement. In addition, students' performance and satisfaction were evaluated. Methodology: Two multimedia-enhanced PBL scenarios were implemented to the third years' students in the urinary system block. Radiological images, plain CT scan, and X-ray of the abdomen and renal nuclear scan correlated with their pathological gross photographs were added to the scenarios. One week before the first sessions, pre-recorded orientation videos for PBL tutors were submitted to clarify the multimedia incorporated in the scenarios. Other two traditional PBL scenarios devoid of multimedia demonstrating the pathological and radiological findings were designed. Results and Discussion: Comparison between the formative assessments' results by the end of the two PBL modalities was done. It revealed significant increase in students' engagement, critical thinking and practical reasoning skills during the multimedia-enhanced sessions. Students' perception survey showed great satisfaction with the new strategy. Conclusion: It could be concluded from the current work that multimedia created technology-based teaching strategy inspiring the student for self-directed thinking and promoting students' overall achievement.

Keywords: multimedia, pathology and radiology images, problem-based learning, videos

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1453 Biodegradation of Malathion by Acinetobacter baumannii Strain AFA Isolated from Domestic Sewage in Egypt

Authors: Ahmed F. Azmy, Amal E. Saafan, Tamer M. Essam, Magdy A. Amin, Shaban H. Ahmed

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Bacterial strains capable of degradation of malathion from the domestic sewage were isolated by an enrichment culture technique. Three bacterial strains were screened and identified as Acinetobacter baumannii (AFA), Pseudomonas aeruginosae (PS1),andPseudomonas mendocina (PS2) based on morphological, biochemical identification and 16S rRNA sequence analysis. Acinetobacter baumannii AFA was the most efficient malathion degrading bacterium, so used for further biodegradation study. AFA was able to grow in mineral salt medium (MSM) supplemented with malathion (100 mg/l) as a sole carbon source, and within 14 days, 84% of the initial dose was degraded by the isolate measured by high performance liquid chromatography. Strain AFA could also degrade other organophosphorus compounds including diazenon, chlorpyrifos and fenitrothion. The effect of different culture conditions on the degradation of malathion like inoculum density, other carbon or nitrogen sources, temperature and shaking were examined. Degradation of malathion and bacterial cell growth were accelerated when culture media were supplemented with yeast extract, glucose and citrate. The optimum conditions for malathion degradation by strain AFA were; an inoculum density of 1.5x 1012CFU/ml at 30°C with shaking. A specific polymerase chain reaction primers were designed manually using multiple sequence alignment of the corresponding carboxylesterase enzymes of Acinetobacter species. Sequencing result of amplified PCR product and phylogenetic analysis showed low degree of homology with the other carboxylesterase enzymes of Acinetobacter strains, so we suggested that this enzyme is a novel esterase enzyme. Isolated bacterial strains may have potential role for use in bioremediation of malathion contaminated.

Keywords: Acinetobacter baumannii, biodegradation, malathion, organophosphate pesticides

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1452 Modeling and Characterization of Organic LED

Authors: Bouanati Sidi Mohammed, N. E. Chabane Sari, Mostefa Kara Selma

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It is well-known that Organic light emitting diodes (OLEDs) are attracting great interest in the display technology industry due to their many advantages, such as low price of manufacturing, large-area of electroluminescent display, various colors of emission included white light. Recently, there has been much progress in understanding the device physics of OLEDs and their basic operating principles. In OLEDs, Light emitting is the result of the recombination of electron and hole in light emitting layer, which are injected from cathode and anode. For improve luminescence efficiency, it is needed that hole and electron pairs exist affluently and equally and recombine swiftly in the emitting layer. The aim of this paper is to modeling polymer LED and OLED made with small molecules for studying the electrical and optical characteristics. The first simulation structures used in this paper is a mono layer device; typically consisting of the poly (2-methoxy-5(2’-ethyl) hexoxy-phenylenevinylene) (MEH-PPV) polymer sandwiched between an anode usually an indium tin oxide (ITO) substrate, and a cathode, such as Al. In the second structure we replace MEH-PPV by tris (8-hydroxyquinolinato) aluminum (Alq3). We choose MEH-PPV because of it's solubility in common organic solvents, in conjunction with a low operating voltage for light emission and relatively high conversion efficiency and Alq3 because it is one of the most important host materials used in OLEDs. In this simulation, the Poole-Frenkel- like mobility model and the Langevin bimolecular recombination model have been used as the transport and recombination mechanism. These models are enabled in ATLAS -SILVACO software. The influence of doping and thickness on I(V) characteristics and luminescence, are reported.

Keywords: organic light emitting diode, polymer lignt emitting diode, organic materials, hexoxy-phenylenevinylene

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1451 Slums in Casablanca: A Conceptive Approach for Better Implementation of VSB Program, Case Study: ER-Hamna Slum

Authors: Sakina Boufarsi, Mehmet Emre Aysu, Behiye Isik Aksulu

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Morocco appears to be on its way to eradicating all of the country's slums by assuring the resettlement and improvement of all affected households' living circumstances through the VSB “Villes sans Bidonvilles” program established in 2004 to eradicate the slums in Morocco. Although many attempts have been made to curb their growth none have proven to be a permanent accomplishment. In Morocco, resettlement projects through satellite towns are perceived as the answer to the problem of the slums. However, the new satellite towns are the good intention of the program VSB, but they are environmentally unsustainable, socially isolated and culturally inappropriate, such conditions imposed continuous readjustments of the slum upgrading program. Although slum research is ongoing, they primarily concentrated on two constructs: exploring socio-economic and policy problems and analyzing physical characteristics. Considering that the two constructs mentioned are crucial, this study will demonstrate that a more systematic approach is needed to eradicate them efficiently. The slums issues in Casablanca are a solution that the poor devise for themselves due to government bureaucracy and failing housing policies, they reflect governments' incapacity to respond to urban development’s requiring decent housing for the vulnerable population. This issue will be addressed by exploring the previous strategies and analyzing in detail the strengths and shortcomings of the recent VSB Program. In addition to a comprehensive overview of the slums' situations by combining the social and physical characteristics through Erhamna case study in Sidi Moumen district for a deeper understanding, and therefore to direct improved and valuable recommendations to address the slum problem at all levels.

Keywords: Casablanca slums, resettlement projects, eradication of slums, satellite town, VSB program

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1450 Molecular Characterization of Cysticercus tenuicolis of Slaughtered Livestock in Upper-Egypt Governorates

Authors: Mosaab A. Omara, Layla O. Elmajdoubb, Mohammad Saleh Al-Aboodyc, Ahmed ElSifyd, Ahmed O. Elkhtamd

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The aim of this study is to present the molecular characterization of cysticercus tenuicolis of Taenia hydatigena from livestock isolates in Egypt, using the amplification of sequencing of the mt-CO1 gene. We introduce a detailed image of the Cysticercus tenuicolis infection in ruminant animals in Upper Egypt. Cysticercus tenuicolis inhabits such organs in ruminants as the omentum, viscera, and liver. In the present study, the infection rate of Cysticercus tenuicolis was found to be 16% and 19% in sheep and goat sample respectively. Firstly we report one larval stage of Taenia hydatigena detected in the camel liver in Egypt. Cysticercus tenuicolis infection manifested a higher prevalence in females than in males. Those above 2 years of age manifested a higher infection rate than younger animals. The preferred site for the infection was the omentum: a 70% preference in sheep and a 68% preference in goat samples. The molecular characterization using the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene of isolates from sheep, goats and camels corresponded to T. hydatigena. For this study, molecular characterizations of T. hydatigena were done for the first time in Egypt. Molecular tools are of great assistance in characterizing the Cysticercus tenuicolis parasite especially when the morphological character cannot be detected because the metacestodes are frequently confused with infection by the Hydatid cyst, especially when these occur in the visceral organs. In the present study, Cysticercus tenuicolis manifested high identity in the goat and sheep samples, while differences were found more frequently in the camel samples (10 pairbase). Clearly molecular diagnosis for Cysticercus tenuicolis infection significantly helps to differentiate it from such other metacestodes.

Keywords: cysticercus tenuicolis, its2, genetic, qena, molecular and taenia hydatigena

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1449 The Role of Bone Marrow Stem Cells Transplantation in the Repair of Damaged Inner Ear in Albino Rats

Authors: Ahmed Gaber Abdel Raheem, Nashwa Ahmed Mohamed

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Introduction: Sensorineural hearing loss (SNHL) is largely caused by the degeneration of the cochlea. Therapeutic options for SNHL are limited to hearing aids and cochlear implants. The cell transplantation approach to the regeneration of hair cells has gained considerable attention because stem cells are believed to accumulate in the damaged sites and have the potential for the repair of damaged tissues. The aim of the work: was to assess the use of bone marrow transplantation in repair of damaged inner ear hair cells in rats after the damage had been inflicted by Amikacin injection. Material and Methods: Thirty albino rats were used in this study. They were divided into three groups. Each group ten rats. Group I: used as control. Group II: Were given Amikacin- intratympanic injection till complete loss of hearing function. This could be assessed by Distortion product Otoacoustic Emission (DPOAEs) and / or auditory brain stem evoked potential (ABR). GroupIII: were given intra-peritoneal injection of bone marrow stem cell after complete loss of hearing caused by Amikacin. Clinical assessment was done using DPOAEs and / or auditory brain stem evoked potential (ABR), before and after bone marrow injection. Histological assessment of the inner ear was done by light and electron microscope. Also, Detection of stem cells in the inner ear by immunohistochemistry. Results: Histological examination of the specimens showed promising improvement in the structure of cochlea that may be responsible for the improvement of hearing function in rats detected by DPOAEs and / or ABR. Conclusion: Bone marrow stem cells transplantation might be useful for the treatment of SNHL.

Keywords: amikacin, hair cells, sensorineural hearing loss, stem cells

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1448 Evaluation of NASA POWER and CRU Precipitation and Temperature Datasets over a Desert-prone Yobe River Basin: An Investigation of the Impact of Drought in the North-East Arid Zone of Nigeria

Authors: Yusuf Dawa Sidi, Abdulrahman Bulama Bizi

Abstract:

The most dependable and precise source of climate data is often gauge observation. However, long-term records of gauge observations, on the other hand, are unavailable in many regions around the world. In recent years, a number of gridded climate datasets with high spatial and temporal resolutions have emerged as viable alternatives to gauge-based measurements. However, it is crucial to thoroughly evaluate their performance prior to utilising them in hydroclimatic applications. Therefore, this study aims to assess the effectiveness of NASA Prediction of Worldwide Energy Resources (NASA POWER) and Climate Research Unit (CRU) datasets in accurately estimating precipitation and temperature patterns within the dry region of Nigeria from 1990 to 2020. The study employs widely used statistical metrics and the Standardised Precipitation Index (SPI) to effectively capture the monthly variability of precipitation and temperature and inter-annual anomalies in rainfall. The findings suggest that CRU exhibited superior performance compared to NASA POWER in terms of monthly precipitation and minimum and maximum temperatures, demonstrating a high correlation and much lower error values for both RMSE and MAE. Nevertheless, NASA POWER has exhibited a moderate agreement with gauge observations in accurately replicating monthly precipitation. The analysis of the SPI reveals that the CRU product exhibits superior performance compared to NASA POWER in accurately reflecting inter-annual variations in rainfall anomalies. The findings of this study indicate that the CRU gridded product is often regarded as the most favourable gridded precipitation product.

Keywords: CRU, climate change, precipitation, SPI, temperature

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1447 Improvement of Data Transfer over Simple Object Access Protocol (SOAP)

Authors: Khaled Ahmed Kadouh, Kamal Ali Albashiri

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This paper presents a designed algorithm involves improvement of transferring data over Simple Object Access Protocol (SOAP). The aim of this work is to establish whether using SOAP in exchanging XML messages has any added advantages or not. The results showed that XML messages without SOAP take longer time and consume more memory, especially with binary data.

Keywords: JAX-WS, SMTP, SOAP, web service, XML

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1446 Critical Review of the Democracy in Pakistan in Light of Dr. Israr Ahmed and Western Philosophers

Authors: Zoaib Mirza

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Pakistan is an Islamic country that got its partition from India in 1947 so that the people could practice the religion of Islam. The ideology of Pakistan was based on the notion that sovereignty only belonged to God Almighty (in Arabic, God means “Allah”), and Muslims will live in accordance with Islam principles. The Quran (Holy Book) and Sunnah (authentic practices of Prophet Mohammad, Peace Be Upon Him, that explains the application of the Quran) are foundations of the Islamic principles. It has been over 75 years, but unfortunately, Pakistan, due to its own political, social, and economic mistakes, is responsible for not being able to become a true Islamic nation to justify its partition from India. The rationale for writing this paper is to analyze the factors that led to changes in the democratic movements impacting the country's political, social, and economic growth. The methodology to examine the historical and political context of Pakistan’s history is by referencing the scholarly work of Israr Ahmed, a Pakistani Islamic theologian, philosopher, and Islamic scholar. While from a Western perspective, Karl Marx, Mar Weber, Hannah Arendt, Sheldon Wolin, Paulo Freire, and Jacques Ranciere's philosophies specific to totalitarianism, politics, military rule, religion, capitalism, and superpower are used as the framework to analyze Pakistan’s democracy. The study's findings conclude that Pakistan's democracy is unstable and has been impacted by military and civilian governance, which led to political, social, and economic downfall. To improve the current situation, the citizens of Pakistan have to realize that the success of a nation is only dependent on the level of consciousness of the leader and not the political system. Therefore, it is the responsibility of every citizen to be conscious of how they select their leader and take responsibility for the current situation in Pakistan.

Keywords: Pakistan, Islam, democracy, totalitarianism, military, religion, capitalism

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1445 Hydraulic Performance of Three Types of Imported Drip Emitters Used in Gezira Clay Soils, Sudan

Authors: Hisham Mousa Mohammed Ahmed, Ahmed Wali Mohamed Salad, Yousif Hamed Dldom Gomaa

Abstract:

A drip or Trickle irrigation system is designed to apply a precise amount of water near the plant with a certain degree of uniformity. This study was conducted at the Experimental Farm of the Faculty of Agricultural Sciences, University of Gezira, in March 2018. The study aimed to design and evaluate the hydraulic performance of three drip emitter types using: average discharge (Qavg), discharge variation (Qvar %), coefficient of uniformity (CU %), coefficient of manufacturer variation (CV %), distribution uniformity (DU %), statistical uniformity (Us %), clogging (%) wetted diameter (cm) and wetted depth (cm). The emitter types used are regular gauges (RG), high compensating pressure (HCP) and low compensating pressure (LCP). The treatments were laid out in a randomized complete block design (RCBD) with four replications. Results showed that there were significant differences (P≤0.05) in all tested parameters except clogging, wetted diameter and wetted depth. Discharge variation (Qvar %) values were 12.71, 15.57 and 19.17 for RG, LCP, and HCP, respectively. The variation is quite good and within the acceptable range. Results of coefficient of manufacture variation (CV %) were 10.9, 27.8 and 52.7 for RG, LCP and HCP, respectively. It is considered within the unacceptable range except for RG type, which is excellent. Statistical uniformity (Us %) values were 89.1, 72.2 and 45.7 for RG, LCP and HCP, respectively. It is considered good, acceptable and unacceptable, respectively. Results of the coefficient of uniformity (CU %) were 91.3, 77.7 and 56.7 for RG, LCP and HCP, respectively. It is considered excellent, fair and unacceptable, respectively. Distribution uniformity (DU %) was 90.2, 67.9 and 36.5 for RG, LCP and HCP, respectively. It is considered excellent, poor and poor, respectively. The study recommended regular gauges (RG) type emitters under the heavy clay soil conditions of the Gezira State, Sudan.

Keywords: drip irrigation, uniformity, clogging, coefficient, performance

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1444 Performance Evaluation of GPS/INS Main Integration Approach

Authors: Othman Maklouf, Ahmed Adwaib

Abstract:

This paper introduces a comparative study between the main GPS/INS coupling schemes, this will include the loosely coupled and tightly coupled configurations, several types of situations and operational conditions, in which the data fusion process is done using Kalman filtering. This will include the importance of sensors calibration as well as the alignment of the strap down inertial navigation system. The limitations of the inertial navigation systems are investigated.

Keywords: GPS, INS, Kalman filter, sensor calibration, navigation system

Procedia PDF Downloads 557
1443 Antimicrobial, Antioxidant Activities and Phytochemical Screening of Five Species from Acacia Used in Sudanese Ethnomedicine

Authors: Hajir Abdllha, Alaa Mohamed, Khansa Almoniem, Naga Adam, Wdeea Alhaadi, Ahmed Elshikh, Ahmed Ali, Ismail Makuar, Anas Elnazeer, Nagat Elrofaei, Samir Abdoelftah, Monier Hemidan

Abstract:

The present study was designed to investigate antimicrobial, and antioxidant activities of five species from Acacia (Acacia albidia, Acacia mellifera, Acacia nubica, Acacia seyal var. seyal and Acacia tortilis). Phytochemical study was piloted to detect the bioactive compounds, which have been responsible from the biological activities. The ethanol, chloroform and acetone plant extracts were seasoned against standard bacteria strains of gram +ve bacteria Staphylococcus aureus (ATCC 25923), Gram -ve bacteria Pseudomonas aeruginosa (ATCC 27853) and standard fungi Candida albicans (ATCC 90028), using cup-plate method. The antioxidant activities were conducted via DPPH radical scavenging and metal chelating assays. Prospective activity against the five species was observed in acetone extract. Ethanol extract showed highest activities against Staphylococcus aureus, and Candida albicans. Potential antioxidant activity was presented by ethanol. Cholorophorm and acetone extracts via DPPH, the radical scavenging activities were found to be 91±0.03, 88±0.01 and 85±0.04 respectively. The results of phytochemical screening showed that all extracts of studied plant contain flavonoids, saponins, terpenoids, steroids, alkaloids, phenols and tannins. This study gives rise to antioxidant, antimicrobial properties of studied plant, and showed interesting correlation with the phytochemical constituents and biological activities.

Keywords: antimicrobial, antioxidant, Acacia albidia, Acacia mellifera, Acacia nubica, Acacia seyal var. seyal, Acacia tortilis

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1442 Steady and Spatio-Temporal Monitoring of Water Quality Feeding Area Southwest of Great Casablanca (Morocco)

Authors: Hicham Maklache, Rajae Delhi, Fatiha Benzha, Mohamed Tahiri

Abstract:

In Morocco, where semi-arid climate is dominant, the supply of industrial and drink water is provided primarily by surface water. Morocco has currently 118 multi-purpose dams. If the construction of these works was a necessity to ensure in all seasons, the water essential to our country, it is impartial to control and protect the quality of running water. -Most dam reservoir used are threatened by eutrophication due to increased terrigenous and anthropogenic pollutants, coming from an over-fertilization of water by phosphorus and nitrogen nutrients and accelerated by uncontrolled development of microalgae aging. It should also be noted that the daily practices of citizens with respect to the resource, an essential component involved in almost all human activities (agriculture, agro-industries, hydropower, ...), has contributed significantly to the deterioration of water quality despite its treatment in several plants. Therefore, the treated water, provides a legacy of bad tastes and odors unacceptable to the consumer. -The present work exhibits results of water quality watershed Oum Erbia used to supply drinking water to the whole terraced area connecting the city of Khenifra to the city of Azemmour. The area south west of Great Casablanca (metropolis of the kingdom with about 4 million inhabitants) supplied 50% of its water needs by sourcing Dam Sidi Said Maachou located, last anchor point of the watershed before the spill in the Atlantic Ocean. The results were performed in a spatio-temporal scale and helped to establish a history of monitoring water quality during the 2009-2011 cycles, the study also presents the development of quality according to the seasonal rhythmicity and rainfall. It gives also an overview on the concept of watershed stewardship.

Keywords: crude surface water quality, Oum Er Rbia hydraulic basin, spatio-temporal monitoring, Great Casablanca drink water quality, Morocco

Procedia PDF Downloads 418
1441 Antimicrobial, Antioxidant Activities, and Phytochemical Screening of Five Species from Acacia Used in Sudanese Ethnomedicine

Authors: Hajir, B. Abdllha, , Alaa, I. Mohamed, Khansa, A. Almoniem, Naga, I. Adam, Wdeea, Alhaadi, Ahmed, A. Elshikh, Ahmed, J. Ali, Ismail, G. Makuar, Anas, M. Elnazeer, Nagat, A. Elrofaei, Samir, F. Abdoelftah, Monier, N. Hemidan

Abstract:

The present study was designed to investigate antimicrobial, and antioxidant activities of five species from Acacia (Acacia albidia, Acacia mellifera, Acacia nubica, Acacia seyal var.seyal and Acacia tortilis). Phytochemical study was piloted to detect the bioactive compounds, which have been responsible from the biological activities. The ethanol, chloroform and acetone plant extracts were seasoned against standard bacteria strains of gram +ve bacteria Staphylococcus aureus (ATCC 25923) ,Gram -ve bacteria Pseudomonas aeruginosa (ATCC 27853) and standard fungi Candida albicans (ATCC 90028), using cup-plate method. The antioxidant activities were conducted via DPPH radical scavenging and metal chelating assays. Prospective activity against the five species was observed in acetone extract. Ethanol extract showed highest activities against Staphylococcus aureus, and Candida albicans. Potential antioxidant activity was presented by ethanol. Cholorophorm and acetone extracts via DPPH, the radical scavenging activities were found to be 91±0.03, 88±0.01 and 85±0.04 respectively. The results of phytochemical screening showed that all extracts of studied plant contain flavonoids, saponins, terpenoids, steroids, alkaloids, phenols and tannins. This study give rise to antioxidant, antimicrobial properties of studied plant, and showed interesting correlation with the phytochemical constituents and biological activities.

Keywords: antimicrobial, Antioxidant, Acacia albidia, Acacia mellifera, acacia nubica, acacia seyal var.seyal, Acacia tortilis

Procedia PDF Downloads 523
1440 Enhancing Warehousing Operation In Cold Supply Chain Through The Use Of IOT And Lifi Technologies

Authors: Sarah El-Gamal, Passent Hossam, Ahmed Abd El Aziz, Rojina Mahmoud, Ahmed Hassan, Dalia Hilal, Eman Ayman, Hana Haytham, Omar Khamis

Abstract:

Several concerns fall upon the supply chain, especially the cold supply chain. According to the literature, the main challenges in the cold supply chain are the distribution and storage phases. In this research, researchers focused on the storage area, which contains several activities such as the picking activity that faces a lot of obstacles and challenges The implementation of IoT solutions enables businesses to monitor the temperature of food items, which is perhaps the most critical parameter in cold chains. Therefore, researchers proposed a practical solution that would help in eliminating the problems related to ineffective picking for products, especially fish and seafood products, by using IoT technology, most notably LiFi technology. Thus, guaranteeing sufficient picking, reducing waste, and consequently lowering costs. A prototype was specially designed and examined. This research is a single case study research. Two methods of data collection were used; observation and semi-structured interviews. Semi-structured interviews were conducted with managers and decision maker at Carrefour Alexandria to validate the problem and the proposed practical solution using IoTandLiFi technology. A total of three interviews were conducted. As a result, a SWOT analysis was achieved in order to highlight all the strengths and weaknesses of using the recommended Lifi solution in the picking process. According to the investigations, it was found that the use of IoT and LiFi technology is cost effective, efficient, and reduces human errors, minimize the percentage of product waste and thus save money and cost. Thus, increasing customer satisfaction and profits gained.

Keywords: cold supply chain, picking process, temperature control, IOT, warehousing, LIFI

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1439 The Impact of Electronic Marketing on the Quality Banking Services

Authors: Ahmed Ghalem

Abstract:

The research to be explained is a collection of information about several public and private economic institutions. This information is represented in highlighting the large and useful role in adopting the method of electronic marketing. Which is widespread and easy to use among community members at the local and international levels. Which generates large sums of money with little effort and little time, and also satisfies the customers. Do these things, despite what we have said, run the risk of losing large amounts of money in a moment or a short time.

Keywords: economic, finance, bank, development, marketing

Procedia PDF Downloads 57
1438 The Issues of Irrigation and Drainage in Kebbi State and Their Effective Solution for a Sustainable Agriculture in Kebbi State, Nigeria

Authors: Mumtaz Ahmed Sohag, Ishaq Ahmed Sohag

Abstract:

Kebbi State, located in the Nort-West of Nigeria, is rich in water resources as the major rivers viz. Niger and Rima irrigate a vast majority of land. Besides, there is significant amount of groundwater, which farmers use for agriculture purpose. The groundwater is also a major source of agricultural and domestic water as wells are installed in almost all parts of the region. Although Kebbi State is rich in water, however, there are some pertinent issues which are hampering its agricultural productivity. The low lands (locally called Fadama), has spread out to a vast area. It is inundated every year during the rainy season which lasts from June to September every year. The farmers grow rice during the rainy season when water is standing. They cannot do further agricultural activity for almost two months due to high standing water. This has resulted in widespread waterlogging problem. Besides, the impact of climate change is resulting in rapid variation in river/stream flows. The information about water bodies regarding the availability of water for agricultural and other uses and the behavior of rivers at different flows is seldom available. Furthermore, sediment load (suspended and bedload) is not measured due to which land erosion cannot be countered effectively. This study, carried out in seven different irrigation regions of Kebbi state, found that diversion structures need to be constructed at some strategic locations for the supply of surface water to the farmers. The water table needs to be lowered through an effective drainage system. The monitoring of water bodies is crucial for sound data to help efficient regulation and management of water. Construction of embankments is necessary to control frequent floods in the rivers of Niger and Rima. Furthermore, farmers need capacity and awareness for participatory irrigation management.

Keywords: water bodies, floods, agriculture, waterlogging

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1437 Experimental Investigation on Performance of Beam Column Frames with Column Kickers

Authors: Saiada Fuadi Fancy, Fahim Ahmed, Shofiq Ahmed, Raquib Ahsan

Abstract:

The worldwide use of reinforced concrete construction stems from the wide availability of reinforcing steel as well as concrete ingredients. However, concrete construction requires a certain level of technology, expertise, and workmanship, particularly, in the field during construction. As a supporting technology for a concrete column or wall construction, kicker is cast as part of the slab or foundation to provide a convenient starting point for a wall or column ensuring integrity at this important junction. For that reason, a comprehensive study was carried out here to investigate the behavior of reinforced concrete frame with different kicker parameters. To achieve this objective, six half-scale specimens of portal reinforced concrete frame with kickers and one portal frame without kicker were constructed according to common practice in the industry and subjected to cyclic incremental horizontal loading with sustained gravity load. In this study, the experimental data, obtained in four deflections controlled cycle, were used to evaluate the behavior of kickers. Load-displacement characteristics were obtained; maximum loads and deflections were measured and assessed. Finally, the test results of frames constructed with three different types of kicker thickness were compared with the kickerless frame. Similar crack patterns were observed for all the specimens. From this investigation, specimens with kicker thickness 3″ were shown better results than specimens with kicker thickness 1.5″, which was specified by maximum load, stiffness, initiation of first crack and residual displacement. Despite of better performance, it could not be firmly concluded that 4.5″ kicker thickness is the most appropriate one. Because, during the test of that specimen, separation of dial gauge was needed. Finally, comparing with kickerless specimen, it was observed that performance of kickerless specimen was relatively better than kicker specimens.

Keywords: crack, cyclic, kicker, load-displacement

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1436 Minimally Invasive versus Conventional Sternotomy for Aortic Valve Replacement: A Systematic Review and Meta-Analysis

Authors: Ahmed Shaboub, Yusuf Jasim Althawadi, Shadi Alaa Abdelaal, Mohamed Hussein Abdalla, Hatem Amr Elzahaby, Mohamed Mohamed, Hazem S. Ghaith, Ahmed Negida

Abstract:

Objectives: We aimed to compare the safety and outcomes of the minimally invasive approaches versus conventional sternotomy procedures for aortic valve replacement. Methods: We conducted a PRISMA-compliant systematic review and meta-analysis. We ran an electronic search of PubMed, Cochrane CENTRAL, Scopus, and Web of Science to identify the relevant published studies. Data were extracted and pooled as standardized mean difference (SMD) or risk ratio (RR) using StataMP version 17 for macOS. Results: Forty-one studies with a total of 15,065 patients were included in this meta-analysis (minimally invasive approaches n=7231 vs. conventional sternotomy n=7834). The pooled effect size showed that minimally invasive approaches had lower mortality rate (RR 0.76, 95%CI [0.59 to 0.99]), intensive care unit and hospital stays (SMD -0.16 and -0.31, respectively), ventilation time (SMD -0.26, 95%CI [-0.38 to -0.15]), 24-h chest tube drainage (SMD -1.03, 95%CI [-1.53 to -0.53]), RBCs transfusion (RR 0.81, 95%CI [0.70 to 0.93]), wound infection (RR 0.66, 95%CI [0.47 to 0.92]) and acute renal failure (RR 0.65, 95%CI [0.46 to 0.93]). However, minimally invasive approaches had longer operative time, cross-clamp, and bypass times (SMD 0.47, 95%CI [0.22 to 0.72], SMD 0.27, 95%CI [0.07 to 0.48], and SMD 0.37, 95%CI [0.20 to 0.45], respectively). There were no differences between the two groups in blood loss, endocarditis, cardiac tamponade, stroke, arrhythmias, pneumonia, pneumothorax, bleeding reoperation, tracheostomy, hemodialysis, or myocardial infarction (all P>0.05). Conclusion: Current evidence showed higher safety and better operative outcomes with minimally invasive aortic valve replacement compared to the conventional approach. Future RCTs with long-term follow-ups are recommended.

Keywords: aortic replacement, minimally invasive, sternotomy, mini-sternotomy, aortic valve, meta analysis

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1435 A Compact Standing-Wave Thermoacoustic Refrigerator Driven by a Rotary Drive Mechanism

Authors: Kareem Abdelwahed, Ahmed Salama, Ahmed Rabie, Ahmed Hamdy, Waleed Abdelfattah, Ahmed Abd El-Rahman

Abstract:

Conventional vapor-compression refrigeration systems rely on typical refrigerants, such as CFC, HCFC and ammonia. Despite of their suitable thermodynamic properties and their stability in the atmosphere, their corresponding global warming potential and ozone depletion potential raise concerns about their usage. Thus, the need for new refrigeration systems, which are environment-friendly, inexpensive and simple in construction, has strongly motivated the development of thermoacoustic energy conversion systems. A thermoacoustic refrigerator (TAR) is a device that is mainly consisting of a resonator, a stack and two heat exchangers. Typically, the resonator is a long circular tube, made of copper or steel and filled with Helium as a the working gas, while the stack has short and relatively low thermal conductivity ceramic parallel plates aligned with the direction of the prevailing resonant wave. Typically, the resonator of a standing-wave refrigerator has one end closed and is bounded by the acoustic driver at the other end enabling the propagation of half-wavelength acoustic excitation. The hot and cold heat exchangers are made of copper to allow for efficient heat transfer between the working gas and the external heat source and sink respectively. TARs are interesting because they have no moving parts, unlike conventional refrigerators, and almost no environmental impact exists as they rely on the conversion of acoustic and heat energies. Their fabrication process is rather simpler and sizes span wide variety of length scales. The viscous and thermal interactions between the stack plates, heat exchangers' plates and the working gas significantly affect the flow field within the plates' channels, and the energy flux density at the plates' surfaces, respectively. Here, the design, the manufacture and the testing of a compact refrigeration system that is based on the thermoacoustic energy-conversion technology is reported. A 1-D linear acoustic model is carefully and specifically developed, which is followed by building the hardware and testing procedures. The system consists of two harmonically-oscillating pistons driven by a simple 1-HP rotary drive mechanism operating at a frequency of 42Hz -hereby, replacing typical expensive linear motors and loudspeakers-, and a thermoacoustic stack within which the energy conversion of sound into heat is taken place. Air at ambient conditions is used as the working gas while the amplitude of the driver's displacement reaches 19 mm. The 30-cm-long stack is a simple porous ceramic material having 100 square channels per square inch. During operation, both oscillating-gas pressure and solid-stack temperature are recorded for further analysis. Measurements show a maximum temperature difference of about 27 degrees between the stack hot and cold ends with a Carnot coefficient of performance of 11 and estimated cooling capacity of five Watts, when operating at ambient conditions. A dynamic pressure of 7-kPa-amplitude is recorded, yielding a drive ratio of 7% approximately, and found in a good agreement with theoretical prediction. The system behavior is clearly non-linear and significant non-linear loss mechanisms are evident. This work helps understanding the operation principles of thermoacoustic refrigerators and presents a keystone towards developing commercial thermoacoustic refrigerator units.

Keywords: refrigeration system, rotary drive mechanism, standing-wave, thermoacoustic refrigerator

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1434 Kinetics and Thermodynamics Adsorption of Phenolic Compounds on Organic-Inorganic Hybrid Mesoporous Material

Authors: Makhlouf Mourad, Messabih Sidi Mohamed, Bouchher Omar, Houali Farida, Benrachedi Khaled

Abstract:

Mesoporous materials are very commonly used as adsorbent materials for removing phenolic compounds. However, the adsorption mechanism of these compounds is still poorly controlled. However, understanding the interactions mesoporous materials/adsorbed molecules is very important in order to optimize the processes of liquid phase adsorption. The difficulty of synthesis is to keep an orderly and cubic pore structure and achieve a homogeneous surface modification. The grafting of Si(CH3)3 was chosen, to transform hydrophilic surfaces hydrophobic surfaces. The aim of this work is to study the kinetics and thermodynamics of two volatile organic compounds VOC phenol (PhOH) and P hydroxy benzoic acid (4AHB) on a mesoporous material of type MCM-48 grafted with an organosilane of the Trimethylchlorosilane (TMCS) type, the material thus grafted or functionalized (hereinafter referred to as MCM-48-G). In a first step, the kinetic and thermodynamic study of the adsorption isotherms of each of the VOCs in mono-solution was carried out. In a second step, a similar study was carried out on a mixture of these two compounds. Kinetic models (pseudo-first order, pseudo-second order) were used to determine kinetic adsorption parameters. The thermodynamic parameters of the adsorption isotherms were determined by the adsorption models (Langmuir, Freundlich). The comparative study of adsorption of PhOH and 4AHB proved that MCM-48-G had a high adsorption capacity for PhOH and 4AHB; this may be related to the hydrophobicity created by the organic function of TMCS in MCM-48-G. The adsorption results for the two compounds using the Freundlich and Langmuir models show that the adsorption of 4AHB was higher than PhOH. The values ​​obtained by the adsorption thermodynamics show that the adsorption interactions for our sample with the phenol and 4AHB are of a physical nature. The adsorption of our VOCs on the MCM-48 (G) is a spontaneous and exothermic process.

Keywords: adsorption, kinetics, isotherm, mesoporous materials, Phenol, P-hydroxy benzoique acid

Procedia PDF Downloads 178