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To assess diffusion tensor imaging (DTI) of spleen in prediction and grading of esophageal varices (OV) in cirrhotic children. This prospective study was conducted upon 30 children with cirrhotic children with OV and 10 age-gender matched controls that underwent DTI of abdomen. Mean diffusivity (MD) and fractional anisotropy (FA) of spleen were calculated and matched with the grading of OV at endoscopy and laboratory biomarkers of portal hypertension. Mean ADC of spleen in patient was significantly different (p = 0.001) from that of controls by both reviewers respectively. The cutoff ADC measurement of the spleen used for prediction of OV was ≥ 0.75 and ≥ 0.76 × 10−3mm2/s with AUC was 0.993 and 0.997 for both reviewers respectively. The FA of the spleen in patient was different (p = 0.01) from of controls of both reviewers respectively. Cutoff FA of spleen used for prediction of OV was ≤ 0.35 and ≤ 0.36 for both observers respectively. ADC and FA of spleen was correlated with platelets count (r = − 0.713, 0.392; p = 0.001, 0.012) and prothrombin time (r = 0.518, − 0.380; p = 0.001, 0.016). DTI metrics of spleen can predict and grade OV and correlated with laboratory biomarkers of portal hypertension.

Ammonia is an important industrial chemical, and its production is one of the highest of all inorganic chemicals. It is synthesized, in principal, from nitrogen and hydrogen by Haber process. It was found that the equilibrium constant (KP) of Haber reaction is strongly pressure dependent. Many correlations were developed in order to rigorously express this (KP); however, the most reliable expressions involved are inherently complex. This paper illustrates a simple correlation which was developed to express the value of (KP) of Haber reaction at temperatures from 350 to 600 °C and pressures from 50 to 300 atm, which covers today’s industrial range. In this correlation, KP is expressed in terms of temperature and pressure of equilibrium mixture which is the direct data measured. The effects of temperature and pressure are not separated allowing KP to be calculated directly, without iterations; using spreadsheet. Results were compared to that of Gillespie and Beattie method showing very good match. The new simple correlation can be used easily in commercial simulation packages, e.g. Hysys, using its embedded spreadsheet to build reliable ammonia synthesis reactor modeling benefiting from featured analysis methods of these packages.

Background: Trans-arterial embolization (TAE) is a prom-ising less aggressive modality in either primary treatment or adjuvant to surgical management of bone tumors. The main aim is to induce necrosis and decrease bleeding and therefore facilitate resection. Palliation of compression manifestation of inoperable bone neoplasm is another indication of TAE. Frequent tumors selected to this modality include vascular tumors (particularly metastases), aneurysmal bone cysts (ABC), giant cell tumor (GCT), and osteosarcoma. Aim of Study: Our aim is to assess the role of embolization in management of bone tumors. Patients and Methods: The current study prospectively evaluated 33 patients (23 males and 10 females). Their age ranged from 9 to 69 years (mean age of 43.246±19.65). Extremities, hip, vertebrae, and skull were involved by variety of bony tumors. Sixteen patients were affected by primary osseous tumors, while 17 patients had metastases. A transar-terial embolization was done in all patients as a preoperative procedure in 15 patients, definite treatmentof primary benign inaccessible tumors in 6 patients, prebiopsy embolization in 6 patients, and as a palliative treatment in 6 patients. Results: Technical success was obtained in 30 out of 33 cases with percentage of 90.9%. All benign and primary malignant bony tumors showed technical success while, 82.4% of metastatic lesions did. Clinical success was achieved in 73.3% cases of first group, 83.3% of second group, 100% of third group and 66.7% of fourth group. Four patients (12.1%) showed no clinical improvement with 9% lost follow-up. Five out of 6 benign tumors showed clinical success (83.3%) as the sixth case lost follow-up (16.7%). Embolization of 9 of primary malignant lesions was clinically successful (90%), whereas 12 out of 17 metastatic lesions were improved clinically (70.6 %), 3 cases showed no clinical success (17.6%), and 2 cases were lost at follow-up (11.8%).Conclusion: A high consideration should be given totran-sarterialembolization in the algorithmic treatment strategy of bone tumors as it is much safer and effective tool when diminution of bleeding and compression manifestations is to be specifically aimed.

Water scarcity and stricter regulations on industrial effluents have led to a different view of water use. Water recycling / reuse is the most common technology used to reduce water and wastewater. The integration of multiple industrial plants, known as the inter-plant integration, has gained a great attention in recent years. Inter- plant water integration is a new technology that can be applied to water integration. This technology can be used to reduce water consumption and water discharge of various water networks in eco-industrial plants. This can be achieved directly or indirectly through the use of regenerators. In this work, a superstructure model for the indirect inter-plant water integration is proposed, for selecting the optimum regenerators of single pass and partitioning regenerators. Mixed integer non-linear program (MINLP) was formulated and solved for optimum solution. A literature case study is used to verify the effectiveness of the proposed model. The results showed that there was a significant decrease in the fresh and the discharge water of the integrated plants.

Alternative Transient Program (ATP) has been steadily developed and improved in the last decades. Today, ATP Draw, a graphical framework, is available, which has improved the use of the program significantly. However, fuzzy controller is one of complex models for which a simplified model can be a very useful tool. This paper introduces a model for fuzzy logic controller in ATP for electromagnetic transients' studies of power system. The proposed model introduces a first model of fuzzy logic in ATP. This facilitates power system and fuzzy logic controller simulation in ATP without needing any other programs. The proposed model is implemented in ATPDraw environment. The proposed fuzzy logic controller model consists of three parts; Membership functions (triangular and trapezoidal shapes), Rules and Defuzzification. The proposed model is verified using numerical examples. The membership degree, the rules, and the defuzzification are calculated using both numerical calculation and the proposed model. The proposed model verification shows acceptable results.

The present study proposed a rigorous model using detailed kinetics reaction for the alkali transesterification of waste cooking oil with methanol and Alkali Catalyst (NaOH). Aspen Plus software is used. The results showed that the rigorousness of the model helps in predicting more realism and accurate result. The effect of different parameters on the process like temperature, pressure, residence time, methanol to oil ratio, and catalyst (NaOH) weight percentage were studied. All the studied parameters have significant effect on the process performance except pressure. Optimization of the process also carried out to find the best conditions for maximum profit and maximum production. The optimization results showed that the reaction temperature decreased from 60 to 45 ° C, the reaction time decreased from 60 to 49 minutes, the molar ratio of methanol/oil increased from 6:1 to 7.2:1 mole ratio and the catalytic concentration decreased from 1 to 0.25 wt%.

Gas processing for natural gas liquids (NGLs) and liquefied petroleum gas ( LPG) recovery is becoming of great interest due to higher sale prices of these products as well as the increase in market demand. However, many of the present recovery units in operation are not giving the desired revenue. The main focuses this study is to retrofit an Egyptian LPG plant for improving NGL recovery. A comparison had been hold between the most applicable cryogenic techniques -in which this plant could be retrofitted to- which can achieve the same targeted cooling and recovery in terms of power consumption and required additional capital cost to detect the best techniques to be applied to maximize NGL liquid Recovery. The replacement of pure propane refrigerant used to C5+ recovery by a mixed refrigerant type was selected as the best techniques which can be applied to improve NGL recovery. Due to its proper physical and thermodynamic properties that lower exergy losses and raise the exchanger effectiveness. Another comparison had been hold to detect which degree of recovery (butane or propane) will be selected for retrofitting the plant and giving the highest return on investment.

Persistent left-sided superior vena cava (PLSVC) is the commonest systemic venous anomaly in the thorax with a reported prevalence of up to 0.5% in otherwise normal population and up to 10% in patients with congenital heart disease (CHD). In the absence of associated CHD, it is usually asymptomatic, discovered incidentally. It may complicate catheter or pacemaker lead placement. PLSVC typically drains into the right atrium through the coronary sinus. In children with CHD, the presence of a PLSVC may affect the choice of certain surgical procedures. PLSVC is significantly more common in association with situs ambiguous than with situs solitus or inversus, up to 60-70%. In patients with situs ambiguous, the drainage of LSVC is variable, more commonly directly into the atria rather than through the coronary sinus (CS). Rarely, there is a PLSVC draining into the CS with absent right SVC. PLSVC draining into the right atrium via the CS will not usually cause blood shunting between the right and the left sides. However, shunting occurs when PLSVC is associated with unroofed CS, or when it directly drains into the left atrium. With an increased use of CT and MRI for chest and cardiac imaging, PLSVC is being more encountered by radiologists than before. In this article, we will discuss the embryology of PLSVC, its anatomic course and drainage pathways, as well as its clinical relevance and relation to congenital heart disease and viscero-atrial situs.

Highlights • Concomitant use of ultrasonography and MIBI-SPECT/CT is highly recommended for better depiction of parathyroid adenoma. • It also helps in accurate localization of parathyroid adenoma especially those of ectopic location. • It will provide better success for parathyroid exploration and minimally invasive surgery., Purpose Evaluating the diagnostic performance of combined protocol of ultrasonography and Tc-99 m MIBI SPECT/CT in preoperative depiction and localization of parathyroid adenoma. Methods and materials 60 patients were enrolled in this retrospective study who had primary hyperparathyroidism and parathyroidectomy for parathyroid adenoma, all of them underwent ultrasonography examination of parathyroid gland and MIBI SPECT/CT for exact pre-operative localization of parathyroid adenoma, surgical and pathological results were used as standard reference then sensitivity, specificity and accuracy for each modalility and for combined protocol of both modalities was calculated. Results The sensitivity, specificity and accuracy were highest with combined protocol of ultrasonography and MIBI-SPECT/CT (87 %), (71 %) and (85 %) respectively and lowest sensitivity, specificity and accuracy with ultrasonography alone (76 %), (63 %) and (73 %) respectively while (83 %), (66 %) and (80 %) with MIBI-SPECT/CT alone. Conclusion Concomitant use of ultrasonography and MIBI SPECT/CT is highly recommended for better preoperative depiction and localization of parathyroid adenoma.

ObjectiveTo predict skull base osteomyelitis in patients with necrotising otitis externa using diffusion-weighted imaging.MethodsA retrospective analysis was conducted of 25 necrotising otitis externa patients with skull base osteomyelitis (n = 10) or without skull base involvement (n = 14) who underwent a single-shot diffusion-weighted imaging of the skull base.ResultsThe respective mean apparent diffusion coefficient values of the skull base, as determined by two reviewers, were 0.851 ± 0.15 and 0.841 ± 0.14 ×10-3mm2/s for the skull base osteomyelitis patients, and 1.065 ± 0.19 and 1.045 ± 0.20 ×10-3mm2/s for the necrotising otitis externa patients without skull base involvement. The difference in apparent diffusion coefficients between the groups was significant, for both reviewers (p = 0.008 and 0.012). The optimal threshold apparent diffusion coefficient for predicting skull base osteomyelitis in necrotising otitis externa patients was 0.945 ×10-3mm2/s and 0.915 ×10-3mm2/s, with an area under the curve of 0.825 and 0.800, accuracy of 87.5 and 83.3 per cent, sensitivity of 85.7 and 90.0 per cent, and specificity of 90.0 and 78.6 per cent, for each reviewer respectively.ConclusionApparent diffusion coefficient is a non-invasive imaging parameter useful for predicting skull base osteomyelitis in necrotising otitis externa patients.

Purpose To assess the role of diffusion tensor imaging metrics in the evaluation of the microstructural integrity of the central auditory tract in patients with idiopathic sensorineural hearing loss (SNHL), and to compare these patients with healthy controls. Material and methods This prospective study, which was conducted upon 30 subjects (21 males, 9 females; age range from 16 to 65 years, mean age 45years) with SNHL proven by audiometric tests. Ten age- and sex-matched healthy volunteers were included as a control group. Patients (n = 30) and volunteers (n = 10) underwent conventional magnetic resonance imaging and diffusion tensor imaging of the brain. Both fractional anisotropy and mean diffusivity (MD) of 3 points along the acoustic tract (inferior colliculus, lateral lemniscus and superior olivary nucleus) were measured bilaterally in all patients and correlated with controls. Results Mean fractional anisotropy (FA) values were reduced bilaterally at the superior olivary nucleus and/or lateral lemniscus and more significantly at the inferior colliculus of subjects with SNHL in comparison to the volunteers. In patients of unilateral SNHL, similar results were obtained in the contralateral side when compared to controls with statistically significant difference at the 3 regions (p = 0.001). No significant changes were noticed in the MD parameters either in patient or control groups. Conclusions The FA value was a valuable non-invasive biomarker in evaluating the subtle microstructural abnormalities of the central auditory tract in idiopathic SNHL and correlated well with hearing impairment.

Inter-plant hydrogen integration (IPHI) is getting more attention in recent years, as a result of the increasing demand for hydrogen in refinery processes, such as hydrotreating and hydrocracking. In this work, IPHI with regeneration scheme is analyzed. Indirect integration scheme is adopted, where hydrogen sources from different hydrogen networks are integrated via a centralized purifier, such as pressure swing adsorption (PSA) or membrane separation. The introduced model is able to select the optimum interception unit, which minimizes the total annualized cost. Besides, multi-period consideration is included in the analysis to address the effect of changes in operating conditions of the IPHI network on total hydrogen consumption. Two case studies are presented to demonstrate the applicability and usefulness of the proposed model. Keywords: Optimization, Optimal design, Hydrogen, Regeneration, Process integration, Multi-period

Petroleum refineries are now facing much tighter and stricter transportation and fuel specification standards, as well as environmental regulations, than in previous years. Therefore, tough rules have been applied on gasoline specifications. Octane number is a key variable of gasoline quality. Isomerization is one of many processes that generate profit by increasing low gasoline octane numbers, with better environmental impacts compared to other processes. Here we analyzed and optimized the various variables affecting the isomerate octane numbers produced by isomerization. Feed composition (naphthenes and benzene content in the feed) and operating conditions (temperature, hydrogen consumption and liquid hourly space velocity) data were collected from the Midor isomerization plant (Egypt) over a 4-year period based on the catalyst lifetime. These data were then used to predict the influence of feed composition and operating conditions on isomerate research octane number using a Response Surface Methodology (RSM) approach (Design Expert software). Thus, we were able to predict isomerate research octane number under various operating conditions. All of the studied variables were found to influence octane number. Keywords: Isomerization process, Operating variables, Octane number, Gasoline

Recently due to the growing demand of natural gas liquids (NGL), there are many processes are existing to make a deep NGL recovery from natural gas. The present study describes the simulation and optimization analyses of NGL recovery for two different processes. The simulation is employed to assess and compare an existing NGL recovery unit at Port Said (EGYPT) in United Gas Derivatives Company (UGDC) which was designed as Improved Overhead Recycle Process (IOR) with anther recovery technology known as the Single Column Overhead Recycle Process (SCORE). The simulation results show that IOR process is more flexible than that SCORE process in the case of changing natural gas feed composition from very rich to very lean gas. Since IOR process can accommodate change in feed gas composition from lean gas range (0.91806 – 0.9620) to rich gas range (0.91806 – 0.85511) based on methane mole fraction. At normal operating condition the fixed capital investment and operating cost for SCORE process is less by $ 25.67E+06 / year than that of IOR process. Also the total production profit for SCORE is more by $ 10.787E+06 / year than total production profit for IOR process. So SCORE process is the technology of choice for plants where high propane recovery and maximum efficiency are of great importance.

Isomerization process became one of the best gasoline production sources, as it gives a high octane product while saving environment from pollution impacts. This paper presents a practical study that aims to improve the gasoline quality and economic income of an existing light naphtha isomerization unit used for octane improvement. The study included selecting the optimum combination of isomerization unit equipment that gives better product specifications for a specified feed. Eight scenarios were studied and simulated to predict the product specs. The original studied unit is MIDOR light naphtha isomerization unit at Alexandria-Egypt that recycles the unconverted hexane (C6). The other studied scenarios were adding fractionators for separating feed iso-pentanes, and recycling unconverted pentanes, hexanes and/or combinations of these fractionators. The results show a change in octane number of gasoline product for a specific feed. Once through process with no extra fractionators has lower octane number of 81 while that with de-iso-pentanizer–de-pentanizer and de-hexanizer produces gasoline with 92.3 octane number. Detailed economic study was done to calculate the return on investment “ROI” for each process option based on equipment, utilities, feed and product prices. Once through simple isomerization unit had the lowest ROI of 14.3% per year while the combination of De-iso-pentanizer with the De-hexanizer had the best ROI of 26.6% per year.

Background The aim of our work was to assess the diagnostic accuracy of a double inversion recovery (DIR) sequence in the detection of brain and spinal cord MS lesions. In addition, we aimed to evaluate the reliability of the correlation between GM affection and high Expanded Disability Status Scale (EDSS) to enhance the role of DIR as a practical test for clinical disability. Ninety MS patients were prospectively included in this study. Imaging was performed using Philips Intera 1.5 Tesla device. T2W-TSE, FLAIR, and DIR sequences were performed and compared to each other. Each patient was clinically assessed at the time of the MRI examination with EDSS. Results DIR showed significantly higher total lesion load in comparison to T2 and FLAIR with increased sensitivity for cortical lesion detection by DIR. There was a positive association between patients with cortical lesions and male gender, clinical disability, cognitive changes, and higher EDSS score. Conclusion The increased rate of cortical lesion detection by DIR does not affect its accuracy in white matter lesions count. Moreover, DIR provided a better morphological characterization and delineation of white matter lesion with good differentiation between juxtacortical and mixed white matter–gray matter lesions; thus, we recommend adding DIR sequence in routine MR protocols for MS patients.

تُعد الماشية (الأبقار والجاموس والماعز والأغنام) من أهم الحيوانات التي تزود الإنسان بالمنتجات الغذائية الرئيسية، كاللحم والحليب ومشتقاتهما، والجلود وبعض المواد البروتينية ومستخلصات الهرمونات، بالإضافة إلى كونها حيوانات عمل (خاصة الأبقار والجواميس) في كثير من بلدان العالم، حيث تساعد على إنجاز كثير من الأعمال الزراعية والفلاحية. وتعتمد صناعة الألبان في العالم على حليب البقر والجاموس بالمقام الأول، ثم حليب الأغنام والماعز. ونظراً لازدياد أعداد البقر والجاموس في العالم، فقد أصبح انتاج الحليب واللحوم ومشتقاتهما وطرق تسويق هذه المنتجات وحفظها وتعليبها، لاستعمالات طويلة الأمد، من أهم ميزات الزراعة الحديثة والتجارة، وبذلك تحولت صناعة الألبان واللحوم إلى علوم لها قواعد وأسس قوية، مرتبطة بالعلوم الأخرى لتحسين نوعية الألبان واللحوم وانتاج أنواع جديدة منها وتسويقها بنجاح وتحقيق عوائد مادية مربحة على المستوى المحلي والعالمي

The increase of hydrogen demand has been one of the focal point recently. Indirect inter-plant hydrogen integration (IPHI) is a new issue for reducing hydrogen consumption and hydrogen discharge, in which hydrogen networks for different plants are integrated indirectly through centralized partitioning regeneration unit where hydrogen is regenerated for further reuse/recycle. This work is an extension of the automated targeting technique that was developed for single hydrogen network and the automated targeting that was developed for inter-plant water integration. The concentration cascade model has been developed to optimize hydrogen networks through partitioning regeneration unit such as pressure swing adsorption (PSA) or membrane separation. Two case studies from literature are studied to illustrate the applicability of the proposed model.

There has been continuous evolution of NG treatment processes to meet the ever– increasing demands of electricity generation and various manufacturing sectors. Our focal point is the booster compression station of an existing gas plant which consists of two centrifugal compressors. The objective of the presented work is to debottleneck both compressor trains to increase its capacity and to study the effect of the proposed modifications on the downstream dehydration package that using adsorption by silica gel fixed beds. The presented modifications are adding two slip steams to the gas/gas heat exchangers, the first one to be installed on tube side and the second one on shell side, each slip stream will accommodate 160 MMscf/d. These will give the compression station an important advantage as the capacity of each train will increase from 450 to 610 MMscf/d per train that means we can got a gain of 320 MMscf/d per both trains to be added to the national gas grid at Egypt. The adsorption performance changed after adding both slip streams where the operating parameters of the inlet gas have changed such as temperature and pressure. The simulations for both cases existing and modifying compression station were conducted using Aspen- HYSYS simulation program. The simulation results shows that fuel gas consumption of both compressors driver gas turbines has increased from 6880 to 10000 Kw that equal 45.0% equivalent to 2.25 MMscf/d (1.125 MMscf/d per each) compared to compressed gas capacity increment by 35.5 % that equal 320 MMscf/d. Adsorption calculation for hydration beds shows that pressure drop per each bed increased from 0.66 to 1.19 bar but still within limit (Max 1.25 bar) and adsorbed water for each bed has increased from 1260 to 2850 lb H2O that equal 1590 lb H2O or 126 % while the bed should hold 6500 lb H2O.

The objectives of this study were to investigate the presence of foodborne pathogen Arcobacter butzleri (A. butzleri) in different types of cheese (Talaga, Mozzarella and Roumy cheese - 30 each) retailed in Assiut dairy shops, Egypt and to test the antimicrobial effect of thyme (Thymus vulgaris) and its essential oil (EO) against isolated strains. The highest percentage of A. butzleri existence was noticed in Talaga cheese samples and confirmed by PCR using A. butzleri. 16S rRNA gene which at the same time, the existence of it in Roumy cheese after detected biochemically. To exam the effect of Thymus vulgaris and its EO on A. butzleri, were added at 2 and 4% concentratins during cheese manufacturing with addition of A. butzleri at 105 and the consumer accepatability was studied. The plant could prohibit the growth of organism in cheese nearly at 6th day. These results suggest that 2% of thyme plant have sufficient effect on A. butzleri with good consumer satisfaction so, it is recommended that e thyme should be used as natural food additive in dairy product in Egypt factories.

Using of series compensation is used in transmission systems to increase the line capacity, improve transient stability, and decrease system losses. Metal oxide varistor (MOV) is used as an overvoltage protection. Application of series compensation results in problems for protection systems of the transmission line, as fault location and distance protection. ATPDraw as an electromagnetic transient simulation tool needs a model for correctly simulation of the adaptive relay. Therefore, this paper proposes an adaptive distance relay model in ATPDraw based on the fuzzy logic-based fault locator. The results confirm the proposed model ability of correctly fault location calculation for series compensation transmission lines using ATPDraw.