oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Search Results: 1 - 10 of 115 matches for " Nariman Houssein "
All listed articles are free for downloading (OA Articles)
Page 1 /115
Display every page Item
Three-port versus four-port laparoscopic cholecystectomy in acute and chronic cholecystitis
Dhafir Al-Azawi, Nariman Houssein, Abu Rayis, Donal McMahon, Dermot J Hehir
BMC Surgery , 2007, DOI: 10.1186/1471-2482-7-8
Abstract: The medical records of 495 patients who underwent LC between September 1999 and September 2003 were reviewed. Variables such as complications, operating time, conversion to open procedure, hospital stay, and analgesia requirements were compared.Two hundred and eighty-three patients underwent three-port LC and 212 patients underwent four-port LC. In total, 163 (32.9%) patients were diagnosed with AC and 332 (67.1%) with CC by histology. There was no statistical difference between the three and four-port groups in terms of complications, conversion to open procedure (p = 0.6), and operating time (p = 0.4). Patients who underwent three-port LC required less opiate analgesia (pethidine) than those who underwent four-port LC (p = 0.0001). The hospital stay was found to be related to the amount of opiates consumed (p = 0.0001) and was significantly shorter in the three-port LC group (p = 0.005).Three-port LC is a safe procedure for AC and CC in expert hands. The procedure offers considerable advantages over the traditional four-port technique in the reduction of analgesia requirements and length of hospital stay.Since its foundation in 1987 by Philip Mouret of Lyon, laparoscopic cholecystectomy (LC) has been the procedure of choice for symptomatic gall bladder disease [1]. Since then, there have been many changes and improvements in the technique. Traditional LC is performed using four-port technique [2,3]. Reducing the size or number of ports did not affect the safety of the procedure and further enhanced the advantages of laparoscopic over open cholecystectomy [4]. These modifications actually reduced the pain and analgesia requirement [5]. Three trocars and even two trocars were used to perform LC [4,6], as has using mini-instruments, authors of these new techniques claimed that these techniques took a similar time to perform and caused less postoperative pain than the standard laparoscopic cholecystectomy [5,7]. Some authors even advised for procedures as needlescope
A Novel Immunological Technique for Detection of Gramicidin (S) Producing Bacteria  [PDF]
Fouad Houssein Kamel
Green and Sustainable Chemistry (GSC) , 2012, DOI: 10.4236/gsc.2012.22009
Abstract: A serological kit was prepared for the first time to detect bacteria that produce Gramicidin (S). Since, an immunocomplex of antibiotic Gramicidin (S) was prepared followed by immunonization of laboratory animales to obtain specific antibodies in their serum. Serial dilutions of the prepared antibodies were tested directly against samples of bacteria and compared with control samples, which include bacteria that produce Gramicidin (S) (as a positive control) and the bacteria that does not produce Gramicidin (S) (as a negative control) depending slide method after the incubation of bacteria in a suitable media for 3 - 4 hours at 37°C. The prepared kites were evaluated in reference Laboratories and they proved to be highly sensitive (100%), specific (100%), more economic and reliable procedure, in addition to its stability for more than one year. It was the first time to prepare a kit for detection of bacteria which produce Gramicidin (S) directly within few minutes.
Planar Inverted-F Antenna (PIFA) Design Dissection for Cellular Communication Application  [PDF]
Nariman Firoozy, Mahmoud Shirazi
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2011, DOI: 10.4236/jemaa.2011.310064
Abstract: An in-depth approach towards the design of PIFA has been taken. After discussing the essential parameters involved in the design procedure and introduction of a design algorithm, a miniaturized dual-band PIFA is introduced. Different specifications of the proposed antenna are measured both through computer simulation and fabricated PIFA. Also, the Specific Absorption Rate (SAR) is introduced and measured for this antenna.
Braid groups and discrete diffeomorphisms of the punctured disk
Sam Nariman
Mathematics , 2015,
Abstract: Morita proved that for large enough $g$ the mapping class group of a surface of genus $g$, denoted by $\mathrm{Mod}(\Sigma_g)$, cannot be realized as a subgroup of the surface diffeomorphism group $\mathrm{Diff}(\Sigma_g)$, by showing that $H^6(\mathrm{Mod}(\Sigma_g);\mathbb{Q})$ is not a summand of $H^6(\mathrm{Diff}(\Sigma_g);\mathbb{Q})$. Surprisingly, the situation is different for the braid groups. While there is no section from braid groups to diffeomorphism groups of punctured disks, as N.Salter and B.Tshishiku recently showed, we prove that the homology groups of the braid group are summands of the homology groups of the discrete diffeomorphisms of a disk with punctures. This situation is similar to the homeomorphism group of a surface of genus $g>5$ where the mapping class group and the homeomorphism group have the same homology but still there is no section from the mapping class group of such a surface to its homeomorphism groups. Using factorization homology, we also show that there is no homological obstruction to realize surface braid groups by diffeomorphism groups of the punctured surface. We prove that discrete diffeomorphism groups of punctured disks exhibit homological stability and their stable homology is the same as the homology of a certain double loop space. As an application of this method, we also prove there is no homological obstruction to lifting the "standard" embedding of $\mathrm{Br}_{2g+2}$ into $\mathrm{Mod}_{g,2}$ to a group homomorphism between diffeomorphism groups.
Stable homology of surface diffeomorphism groups made discrete
Sam Nariman
Mathematics , 2015,
Abstract: We answer affirmatively a question posed by Morita on homological stability of surface diffeomorphisms made discrete. In particular, we prove that $C^{\infty}$-diffeomorphisms and volume preserving diffeomorphisms of surfaces as family of discrete groups exhibit \emph{homological stability}. We show that the stable homology of $C^{\infty}$-diffeomorphims of surfaces as discrete groups is the same as homology of certain infinite loop space related to Haefliger's classifying space of foliations of codimension 2. We use this infinite loop space to obtain new results about (non)triviality of characteristic classes of flat surface bundles.
Homological stability and stable moduli of flat manifold bundles
Sam Nariman
Mathematics , 2014,
Abstract: We prove that group homology of the diffeomorphism group of $\#^g S^n \times S^n$ as a discrete group is independent of $g$ in a range, provided that $n>2$. This answers the high dimensional version of a question posed by Morita about surface diffeomorphism groups made discrete. The stable homology is isomorphic to the homology of a certain infinite loop space related to the Haefliger's classifying space of foliations. One geometric consequence of this description of the stable homology is a splitting theorem that implies certain classes called generalized Mumford-Morita-Miller classes can be detected on flat $(\#^g S^n \times S^n)$-bundles for $g$ big enough.
On a new method for calculation of the number of prime numbers in the given interval
Nariman Sabziyev
Mathematics , 2013,
Abstract: Definition of the number of prime numbers in the given interval
Adhesion on Nanoorganized Multilayers
Yolla Kazzi,Houssein Awada
Advances in Physical Chemistry , 2011, DOI: 10.1155/2011/850243
Abstract: Nanostructured multilayers composed of alternate organic (alkyldithiol) and metallic (gold) layers are grafted onto glass plates and prepared in order to modify the mechanical and local dissipative properties of a thin surface layer of the substrate. The adhesion phenomenon between a polyisoprene elastomer and these layers is presented and verified by two theories, namely, Johnson, Kendall, Roberts (JKR) and linear elastic fracture mechanics. The increase in adhesion with contact time following a power law has been clearly noted. 1. Introduction The adhesive failure energy of adhesive joints formed at a low contact pressure during a short contact time is called “tack strength” [1]. Tack represents a limited case of adhesion. It is a property which reflects the ability of a material to adhere instantaneously to a rigid surface, under a low pressure carried out for a short time [2]. Tack is of considerable interest in the field of adhesives and bonding in particular for pressure-sensitive adhesives (PSAs) such as adhesive labels [3]. The use of adhesives is becoming more frequent and their use on several systems requires an in depth understanding of the mechanisms governing their properties. To date, the respective influences on the adhesion of interfacial interactions and phenomena of local dissipation energy, immediately close to the interface, have not yet been fully established. Interfacial interactions and the dissipation energy both in the volume of materials and near the interface determine, to a large extent, the adhesion energy between two solids in contact. In the present study, we try to focus on this local dissipation at the interface not in the bulk of the material. To achieve our goal, thin multilayers, alternatively organic (alkyldithiol, PDMS) and metallic (gold), are deposited on glass plates in order to modify the mechanical properties and local dissipation on the substrate surface. An adhesion promotor (organosilanes terminated thiol) is first grafted onto the hydrophilic substrate, allowing the deposit of a gold layer by thermal evaporation. Successive layers of alkyldithiol (or polydimethylesiloxane) and gold can be carried out. The external face is either gold-or alkyldithiol-terminated methyl allowing the study of the surfaces of different thermodynamic characteristics (Figure 1). Figure 1: Schematic representation of the nanostructured multilayers. The scale between molecules and gold layers is not proportional. The chemical and structural characterization of these self-assembled layers as well as the study of their adhesive
Improving the Performance of Wireless Ad-hoc Networks: Accounting for the Behavior of Selfish Nodes
Houssein Hallani,Seyed Shahrestani
Communications of the IBIMA , 2011,
Abstract: Modern Wireless Local Area Networks (WLANs) with relatively high data rates have become an attractive technology for providing Internet connectivity for mobile users. Ad-hoc networks are a collection of mobile nodes that can be deployed without the need for any centralized management infrastructure. In such a set-up, to establish the required communication paths, each node must be willing to act as a potential router. In practice though, some nodes may act selfishly and refuse to forward packets. In Ad-hoc networks, a node may be considered as misbehaving for different reasons, for instance when it acts selfishly, refusing to forward packets. In some circumstances, the node can be overloaded, or they simply want to save their resources by not forwarding packets unless they are of direct interest to the node itself. Conversely, these nodes may still be expecting others to forward packets on their behalf In this paper, we report the experimental results obtained from a typical Ad-hoc networks that contain selfish nodes. We also analyze the behavior of the nodes, to establish some quantifiable measure of their reliability. Such measures, based on the behavior history of the nodes, are then utilized to improve the performance and reliability of the widely used Ad-hoc On Demand Distance Vector routing protocol. We also report the results of simulations of large Ad-hoc networks in the presence of malicious or selfish nodes. These results clearly indicate the capabilities of the proposed approach in discovering communication paths with a minimal number of malicious or selfish nodes.
Complexity of modules over classical Lie superalgebras
Houssein El Turkey
Mathematics , 2014,
Abstract: The complexity of the simple and the Kac modules over the general linear Lie superalgebra $\mathfrak{gl}(m|n)$ of type $A$ was computed by Boe, Kujawa, and Nakano in 2012. A natural continuation to their work is computing the complexity of the same family of modules over the ortho-symplectic Lie superalgebra $\mathfrak{osp}(2|2n)$ of type $C$. The two Lie superalgebras are both of Type I which will result in similar computations. In fact, our geometric interpretation of the complexity agrees with theirs. We also compute a categorical invariant, z-complexity, introduced in Boe et al., and we interpret this invariant geometrically in terms of a specific detecting subsuperalgebra. In addition, we compute the complexity and the z-complexity of the simple modules over the Type II Lie superalgebras $\mathfrak{osp}(3|2)$, $D(2,1;\alpha)$, $G(3)$, and $F(4)$.
Page 1 /115
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.