Effect of Unfolding on the Spectral Statistics of Adjacency Matrices of Complex Networks

Random matrix theory is finding an increasing number of applications in the context of information theory and communication systems, especially in studying the properties of complex networks. Such properties include short-term and long-term correlation. We study the spectral fluctuations of the adjacency of networks using random-matrix theory. We consider the influence of the spectral unfolding, which is a necessary procedure to remove the secular properties of the spectrum, on different spectral statistics. We find that, while the spacing distribution of the eigenvalues shows little sensitivity to the unfolding method used, the spectral rigidity has greater sensitivity to unfolding.Comment: Complex Adaptive Systems Conference 201

Empirical Study of Traffic Velocity Distribution and its Effect on VANETs Connectivity

In this article we use real traffic data to confirm that vehicle velocities follow Gaussian distribution in steady state traffic regimes (free-flow, and congestion). We also show that in the transition between free-flow and congestion, the velocity distribution is better modeled by generalized extreme value distribution (GEV). We study the effect of the different models on estimating the probability distribution of connectivity duration between vehicles in vehicular ad-hoc networks.Comment: 5 pages, 5 figures, presented at the ICCVE 2014 (International conference on connected vehicles & expo); http://www.iccve.org

Well bore instability mechanisms in clays

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 2011."February 2011." Cataloged from PDF version of thesis.Includes bibliographical references (p. 331-341).This dissertation investigates the stability of wellbores drilled in Ko-consolidated clays using non-linear finite element method (FEM) and effective stress soil models to characterize the behavior of clay and unconsolidated shale formations. Two constitutive models are used: Modified Cam Clay (MCC; Roscoe and Burland, 1968), and MIT-E3 (Whittle and Kavvadas, 1994). These soil models are incorporated in the commercial finite element program ABAQUS TM through user material subroutines (Hashash, 1992). The wellbores are modeled by a quasi-3D finite element model to approximate the far field stresses and plane strain boundary conditions. The constitutive models are calibrated to the behavior of Resedimented Boston Blue Clay (RBBC), an analog shale material which is Ko-consolidated to stress levels ranging from 0.15MPa to 10.0 MPa. The thesis comprises three major parts. Part one analyzes the short-term wellbore instability during drilling in low permeability formations. The part focuses on the relationship between the mud pressure inside the wellbore and the undrained shear deformations within the formations. The analyses predict critical mud pressure values necessary to maintain wellbore stability at different deviation angles and stress histories. The MIT-E3 model predicted higher deformations at reference mud pressure and estimated higher values of mud pressures than the underbalanced limit to prevent failure in highly deviated wellbores in NC clays. The second part validates the numerical analyses by comparing model predictions to results of an extensive program of model borehole tests. The lab experiments are performed on high pressure Thick- Walled Cylinder (TWC devices) using RBBC as analog testing material (Abdulhadi, 2009). The MIT-E3 predictions demonstrated a very good match with results from the experiments. The results from the analyses illustrated the effect of the device boundary conditions on specimen behavior and validated approximate analytical methods for interpreting TWC results. Part three studies the effects of consolidation on long-term wellbore stability. Non-linear coupled consolidation analyses are performed to simulate the post-drilling, time-dependent deformations and pore pressures around the wellbore. The analyses consider two different boundary conditions on seepage at the cavity. The analyses show that consolidation generates extensive volumetric strains around the wellbore and cavity deformations can aggravate stability conditions in highly deviated wellbores.by Sherif Adel Akl.Ph.D

Review - Challenges of mobility aware MAC protocols in WSN

© 2018 IEEE. In today\u27s smart world WSN plays an important role in IoT. The WSN nodes can be used for wildlife, patient, air quality monitoring. WSN consists of numerous sensor nodes that are connected to each other. One of the major concerns of WSN is the mobility of nodes. The mobility of the nodes creates concern to the MAC protocols that\u27s defined for WSN static nodes. Mobile-WSN demands the participated nodes to send packets with a bursty traffic, low energy consumption and reliable connection. MAC protocol is the most important in designing the WSN as MAC plays an important role regarding throughput, mobility, security and energy consumption. This paper gives a review on mobility aware protocols such as M-MAC, MA-MAC, MMH-MAC, M-Contiki, MobiIQ, MobiDisc

Percutaneous drainage of delayed post-cardiac surgery pericardial effusion

Background: Pericardial effusion and tamponade are common following valve surgery. The optimal treatment of symptomatic pericardial effusions remains controversial. The objective of this study was to present our experience in non-surgical management of delayed postoperative pericardial effusion. Methods: This retrospective study was conducted on 64 patients who had delayed pericardial effusion after cardiac surgery from 2016 to 2020. Eight patients were excluded due to the presence of inaccessible posterior or clotted pericardial effusion and were managed surgically, and 56 patients had percutaneous drainage of the pericardial fluid and were included in the analysis. Results: The mean age was 46.84±11.67 years (range: 22- 68 years), and 46.43% were females. The patients had coronary artery bypass grafting (n= 9), Aortic valve replacements  (n= 13), Mitral valve surgery (n= 21), double valve replacements (n= 8) and  combined procedures (n= 5).  All patients complained of varying degrees of exertional dyspnea. There were statistically significant differences between INR in different cardiac surgeries. Mean INR following mitral valve replacement (4.72±0.63) was significantly higher than in aortic valve replacement patients (3.32±0.34; p<0.001) and aortic valve patients (1.76±0.24; p<0.001). Fifteen patients (26.78%) had a large pericardial effusion. Successful drainage was achieved in all cases. Complications were pneumothorax (n= 2, 3.57%), recurrent effusions (n= 4, 7.14%), arrhythmias (n= 7, 12.5%), myocardial punctures (n= 2, 3.57%) and no mortality was reported. Conclusions: percutaneous drainage of postoperative pericardial effusion under radiological guidance is generally safe. Pericardial effusion is common after mitral valve surgery, which could be related to higher INR in these patients

Plasma level of interleukin 37 in children with primary immune thrombocytopenia

Background: Interleukin (IL)-37, a novel anti-inflammatory cytokine previously known as interleukin-1 family member 7 before it was renamed, has a pivotal role in the suppression of immune responses. Objective: The present study aimed to investigate the expression of IL-37 and its potential role in the pathogenesis of immune thrombocytopenia (ITP). Patients and Methods: The study was carried out in Zagazig University Hospital, Pediatric Department. The total sample size was 60 participants divided into 4 groups. They were 45 patients (15 patients with newly diagnosed ITP, 15 patients with complete remission after 1st line therapy and 15 patients with chronic ITP) and 15 age - sex matched healthy children as a control group.Results: Our study showed that the mean value of age among patients group was (6.89± 4.13) with female predominance than males (60%). The current work showed that regarding history of bleeding tendency it was present in 45 (100%). This study showed the bone marrow examination was done for 8 of our patients (17.8%) and revealed hypercellular megakaryopoiesis. In the current study there was no statistically significant difference between patients group and control group regarding hemoglobin (HB) and white blood cells (WBC). Our study showed that there was no statistically significant correlation between IL 37 level and platelets in patients group.Conclusion: Accumulating evidence suggests that serum level of IL 37 has a pivotal role in autoimmune diseases. In the present study, the expression of IL-37 in ITP patients was evaluated for the first time in Egypt, but no significant abnormal expression of IL-37 was identified in these patients. It was therefore concluded that serum level of IL 37 may not have a pivotal role in the development of ITP

An Extended Semantic Interoperability Model for Distributed Electronic Health Record Based on Fuzzy Ontology Semantics

Semantic interoperability of distributed electronic health record (EHR) systems is a crucial problem for querying EHR and machine learning projects. The main contribution of this paper is to propose and implement a fuzzy ontology-based semantic interoperability framework for distributed EHR systems. First, a separate standard ontology is created for each input source. Second, a unified ontology is created that merges the previously created ontologies. However, this crisp ontology is not able to answer vague or uncertain queries. We thirdly extend the integrated crisp ontology into a fuzzy ontology by using a standard methodology and fuzzy logic to handle this limitation. The used dataset includes identified data of 100 patients. The resulting fuzzy ontology includes 27 class, 58 properties, 43 fuzzy data types, 451 instances, 8376 axioms, 5232 logical axioms, 1216 declarative axioms, 113 annotation axioms, and 3204 data property assertions. The resulting ontology is tested using real data from the MIMIC-III intensive care unit dataset and real archetypes from openEHR. This fuzzy ontology-based system helps physicians accurately query any required data about patients from distributed locations using near-natural language queries. Domain specialists validated the accuracy and correctness of the obtained resultsThis work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2021R1A2B5B02002599)S

Evaluation of Antioxidants Status at Diagnosis in Childhood Acute Lymphoblastic Leukemia

Background: Acute lymphoblastic leukemia (ALL) is a neoplastic disease of immature lymphocytes or lymphocyte progenitor cells either the B- or T-cell lineage. It is the most common malignancy diagnosed in patients younger than 15 years, and account for approximately 25-30% of adult acute leukemia. Objective: To evaluate some antioxidants as zinc, selenium, vitamin A (retinol) and vitamin E (tocopherol) status at diagnosis of childhood acute lymphoblastic leukemia and to compare it to that of a control population. Patients and methods: This case-control study was carried out at Oncology Unit of Pediatrics Department and Medical Biochemistry Department, Faculty of Medicine, Zagazig University Hospitals. This study consisted of two groups: Patients’ group (30 children patients with newly diagnosed ALL). As regard control group, it included 30 healthy children who were matched well with patients’ age and sex. Fasting levels of serum zinc, selenium, retinol and tocopherol were measured. Results: There was a high statistically significant decrease of vitamin E, selenium and zinc among all cases than their controls. While, there was a significant increase of vitamin A among all cases. Zinc level was statistically significantly increased with increased risk of disease, while no statistically significant relation between disease risk and other levels of serum antioxidant. Conclusion: Some antioxidants as zinc, selenium and vitamin E (tocopherol) status at diagnosis of childhood acute lymphoblastic leukemia are lower compared to that of a control population