59. Early and late results of routine leaflet augmentation for complete atrio-ventricular septal defect repair

Complete AVSD (CAVSD) is characterized by the presence of a common atrio-ventricular (AV) orifice, an inter-atrial communication, and a ventricular septal defect (VSD). Results of surgical correction of atrio-ventricular septal defects (AVSDs) have improved over the last decades; however, the need for reoperation for left atrio-ventricular valve regurgitation, after primary AVSD repair remains a major concern. The aim of our study is to assess the outcome of the routine leaflet augmentation technique in CAVSD repair. A retrospective database and chart review analysis of all patients who underwent AV canal repair at king Abdul-Aziz Cardiac Center during period from 1999 to September 2014 was conducted. Demographic data, associated anomalies, operative data, ICU and hospital course were reviewed. Early outcomes were reviewed for postoperative complications (Chylothorax, complete AV block, Arrhythmias, early mortality) and late outcomes were reviewed for Left AV valve regurgitation requiring for re-intervention and late mortality. Two hundred and sixty patients underwent leaflet augmentation technique to repair complete AVSD, between January 1999 and September 2014. The mean age was (131.5months), and mean weight (6.06kg). A variety of concomitant procedures were performed at the time of repair of the CAVSD, including a total of 49 patients (18.8%) who underwent PDA ligation. Repair of TV (Right AV valve) was performed in 11 patients (4.2%), 9 patients (3.46%) required RVOTO resection, in 5 patients (1.92%), PA plasty was done and 2 patients (0.76%) required ECMO after CAVSD repair. Regarding reoperations, a total of 17 patients (of 260) required reoperation after initial CAVSD repair. The most common indication for reoperation was left AV valve regurgitation in 16 patients (6%) in the follow up period up to 15years. One patient (0.38%) required diaphragmatic plication. The overall mortality was 3 patients (1.1%). Leaflet augmentation for the repair of the complete AVSD, represent a good surgical alternative technique, allows for good exposure, good LAVV reconstruction and close to anatomical repair and results in reduced incidence of late Left atrio-ventricular valve regurgitation

Progress in the development of sour corrosion inhibitors: Past, present, and future perspectives

Metallic pipelines and gathering tanks play a vital role during oil and gas exploration, production, transmission, and processing. These facilities are usually attacked by corrosion. The use of corrosion inhibitors is one of the most economical and reliable approaches to control the corrosion of oil and gas metallic facilities. This paper looks at the progress made in the development of sour corrosion inhibitors from early 1900 to date. Scientific literatures were reviewed. The review identified four classes of organic corrosion inhibitors for sour environments, namely, amine-based, imidazoline-based, polymer-based, and Gemini-surfactant-based inhibitors. The strengths and weaknesses of these inhibitors were highlighted. The review revealed that the patronage of amine-based chemistries has declined, and the current technology is based on imidazoline and quaternary salt chemistries. The existing knowledge gap and the future research direction in the area of sour corrosion inhibitors development have been highlighted

Relative Mutagenecity of Some Food Preservatives on Plant Cells

Abstract: The present investigation was designed to evaluate the mutagenic activity of food preservatives sodium metabisulphite (SMB) and potassium metabisulphite(KMB) in Vicia faba root meristems. The effect on protein banding pattern and isozyme variations were also investigated. The tested chemicals significantly decreased the mitotic index (MI), and increased the mitotic abnormalities. Reduction in the mitotic activity and induction of chromosomal aberrations were dosedependent at all concentrations and treatment periods..These abnormalities include stickiness, cmitosis, laggards, bridges, micronuclei, fragments and unseparated. All treatments changed the frequency of mitotic phases when compared with the control groups. At SDS-protein level, the studied chemicals show many alterations in the leave storage protein banding patterns expressed as disappearance of some bands or appearance of novel one or change in bands intensity. Also there was a change in the expression level of peroxidase and this regulation was estimated by the band density

Architecture, Digital Techniques and Project Management

With the invention of computers, Architecture and other Engineering disciplines have undergone revolutionary developments offering new opportunities for improving efficiency and opening new frontiers for creativity. For example in architecture and urban planning, the discussions have been extended from conventional writings to cover cyberspace, virtual architecture and digital city. Moreover, computers have helped in the realization of many complex projects that would be inconceivable with traditional drawing techniques. This is clearly demonstrated in the works of Frank Gehry's, Zaha Hadid, Daniel Libeskind and many others. In deed, digital techniques have changed the design creative process and how the architects think. Traditionally the structured development architectural ideas from 2D drawings (plans, sections, elevations) towards 3D resolution has been replaced by more interactive approach of 2D & 3D. The changes that digital techniques have brought to the field of Architecture, including practice and education, can obviously be viewed from different angles and incite many discussions and questions. However, the purpose of this presentation is to discuss the role of digital techniques within the overall framework of project management in Gulf Housing Engineering. It starts the discussion with a brief on architecture and digital techniques in the Gulf Region, especially during the “boom period”, a period characterized by rapid production of buildings relying heavily on virtual images. It is against this background, the role of digital techniques is evaluated from a practice point of view. In fact in GHE, digital means are integral parts of the holistic project delivery process starting form initiation, to various design stages to construction ending with project completion. In this process emphasis is paid to the inter-relationships between IT Systems and Quality Control which in turn facilitate measuring, monitoring and reporting on various managerial, technical and design and budgetary aspects of the project. The presentation is supported by real case studies of GHE portfolio. It emphasizes that digital techniques should be an integral part of an overall process and should be seen as means to enhance efficiency and creativity, and should contribute to the betterment of the built environmen

Periodic density functional investigation of Bronsted acidity in isomorphously substituted chabazite and AlPO-34 molecular sieves

The relative strength of Bronsted acid sites in isomorphously substituted chabazite (M-CHA; Me = Al3+, Ga3+, B3+, SC3+ and Fe3+) and aluminophosphate-34 (MAIPO-34; Me = Ti4+, Si4+, Cr2+, Mn2+, Fe2+, Co2+ and Ni2+) have been investigated using periodic density functional theory. Adsorption energy of NH3 and deprotonation energy are considered for measuring the acidity. It has been found that Al3+-CHA and Mn2+-AlPO-34 possess the strongest acidic character. Moreover, a correlation between deprotonation energy and adsorption energy of NH3 has been observed. (C) 200

H-MOR: Density functional investigation for the relative strength of Bronsted acid sites and dynamics simulation of NH3 protonation-deprotonation

The adsorption energies of NH3 at different positions in acidic mordenite, viz., main channel, side pocket, and double four-membered rings, are investigated using periodic density functional theory method. Furthermore, for the first time, the dynamic behavior of NH3 interacting with Bronsted acid site in the main channel has been monitored. The results reveal that the adsorption energies of ammonia on Bronsted acid sites in the main channel (T-4, T-2, and T-1) are higher than that in the side pocket (TA Consequently, the strength of Bronsted acid sites follows the same order. Ammonia dynamics results show that the protons are in continuous transfer, where NH3 acts as a bridge for transferring protons in between ammonium ion and framework oxygen ions. (c) 200

Whole genome characterization of methicillin resistant Staphylococcus aureus in an Egyptian Tertiary Care Hospital

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a significant healthcare-associated (HA-MRSA) pathogen due to its increased morbidity and mortality rates. There is a paucity of data regarding MRSA clones circulating in the Middle East in the literature, especially from Egypt. We aimed to identify the pattern of resistance and virulence in the propagating clones using NGS technologies for the whole genome sequence. Methods: From an 18-month surveillance program for MRSA-positive patients, 18 MRSA isolates from surgical healthcare associated infections were selected. The Vitek2 system was used to assess antimicrobial susceptibility. The whole genome sequencing was performed using the NovaSeq6000. The reads were mapped to the reference genome (Staphylococcus_aureus_ATCC_BAA_1680), used for variant calling, screened for virulence/resistance genes, and typed using multi-locus sequence typing and spa typing. Correlation between demographic and clinical data and molecular findings were performed. Results: All the MRSA isolates were highly resistant to tetracycline followed by gentamicin (61%) and highly susceptible to trimethoprim/sulfamethoxazole. Most of the isolates showed a high virulence profile. ST239 was the predominant sequence type (6/18), while t037 was the predominant spa type (7/18). Five isolates shared the same ST239 and spa t037. ST1535, an emerging MRSA strain, was the second most prevalent in our study. One isolate showed a unique pattern of a high abundance of resistance and virulence genes. Conclusion: WGS elucidated the resistance and virulence profiles of MRSA isolated from clinical samples of HAI patients with high-resolution tracking of clones predominant in our healthcare facility

Novel computational chemistry approaches for studying physico-chemical properties of zeolite materials

Computational chemistry has made tremendous impact on the development of zeolite materials. Molecular dynamics (MD), Monte Carlo (MC), quantum chemistry (QC), and quantum chemical molecular dynamics (QCMD) methods have been applied to the studies of diffusion processes, adsorption characteristics, catalytic reaction mechanism, synthesis processes, acidic properties, etc. in zeolite materials. However, these traditional approaches are not able to accommodate complicated realistic systems because of their approximations and of the limitation of calculation models. To establish a novel computational chemistry approach for exploring new physico-chemical properties of zeolite materials, we have developed a novel dual ensemble MID (DEMD) program and original tight-binding QCMD program, 'Colors'. The DEMD program can perform the permeation and separation dynamics simulation considering the gradient of chemical potential in a simulation cell. Colors program is over 5000 times faster than the traditional first-principles QCMD simulator. Hence, it enables us to employ more realistic large-scale models. Furthermore, we have also performed large-scale QC calculations based on the density functional theory (I)FT) with a whole unit cell model of a zeolite material considering the periodic boundary condition (PBC). In this review, we put forward the application of our novel theoretical approaches for studying physico-chemical properties of zeolite materials. (c) 2007 Elsevier Inc. All rights reserved