Network Coding-based Protection Strategies Against a Single Link Failure in Optical Networks

In this paper we develop network protection strategies against a single link failure in optical networks. The motivation behind this work is the fact that $$ of all available links in an optical network suffers from a single link failure. In the proposed protection strategies, denoted NPS-I and NPS-II, we deploy network coding and reduced capacity on the working paths to provide a backup protection path that will carry encoded data from all sources. In addition, we provide implementation aspects and how to deploy the proposed strategies in case of an optical network with $n$ disjoint working paths.Comment: 6 pages, 3 figures, ICCES '0

Evaluation of laparoscopic-assisted anorectoplasty for the management of intermediate and high anorectal malformations in boys: Mansoura experience

Introduction: Laparoscopic-assisted anorectoplasty (LAARP) has been gaining great popularity for management of imperforate anus. This study aims to evaluate the use of this technique for high and intermediate anorectal malformations in boys.Patients and methods: From December 2012 to December 2016, we performed LAARP on 20 boys, all of which were colostomized at birth. Findings regarding the patients’ age at operation, type of anomaly, associated morbidities, sacral ratios, operative time, intraoperative complications, hospital stay, immediate/long-term postoperative complications, and reoperations were noted. Postoperatively, we evaluated the patients using barium enema, an ascending and voiding cystourethrogram, pelvic MRI, and a functional continence evaluation questionnaire.Results: A total of 11 patients presented with rectourethral bulbar fistula (RBF), seven with rectourethral prostatic fistula (RPF), one with rectovesical fistula, and one with no fistula. Mean sacral ratio was 0.82 ± 0.19. Mean age at time of LAARP was 236 ± 77 days. Mean operative time was 152 ± 32 min. Our most common intraoperative complication was peritoneal contamination (20%). Incidence of rectal mucosal prolapse was 40%. Barium enema revealed a mean rectoanal angle of 107 ± 13°. Ascending and voiding cystourethrogram revealed a residual urethral diverticulum in seven cases, six of which had RBFs. Mean MRI placement score obtained was 0.76± 0.51 denoting excellent rectal position.Conclusion: Usage of LAARP to manage high and intermediate anorectal malformations in boys is feasible, allowing accurate rectal placement within the muscle complex and with good postoperative functional results. Residual urethral diverticulum occurred more frequently in patients with RBF. Incidence of mucosal prolapse is high after LAARP and should be avoided.Keywords: laparoscopic-assisted anorectoplasty, anorectal malformations, residual urethral diverticulum post LAAR

Improved Refractory Aluminosilicate Bricks Through Nano Zirconia Additions

The physico-mechanical and refractory properties of refractory bricks, prepared from 50 wt.% kaolin and 50 wt.% alumina, were improved through the addition of different contents (2, 4, 6, 8 and 10 wt. %) of nano zirconia powder. The densification parameters (bulk density and apparent porosity), mechanical properties (cold crushing strength) and refractory properties (thermal shock resistance) were tested for the prepared refractory bricks fired at 1500 oC. The mineralogical composition of the prepared zirconia and the refractory bricks were followed by X-ray diffraction analysis (XRD) whereas while their microstructure and chemical constituents were depicted using scanning electron microscope attached with energy dispersive x-ray unit (SEM + EDAX). The refractory brick samples containing 8 wt. % of nano zirconia was considered as the optimum among the investigated samples as it shows the best sintering, mechanical and refractory properties, these were correlated with their recognized assemblage of minerals; mullite-cristobalite-zirconia

New Mixed Ligand Complexes of Ditertiary Phosphanes with Ni(II) Alkylxanthates

Mixed Iigand complexes of Ni(II) with alkylxanthates and ditertiary phosphanes of the composition Ni(ROCSSb(diphoshhave been prepared, where R = methyl, ethyl, propyl, butyl, and cyclohexyl and diphos = bis(diphenylphosphino)ethane (dpe) and bis- (diphenylphosphino)butane (dpb). The newly prepared compounds were characterized on the basis of chemical analyses, infrared and electronic spectra, lH-NMR, molar conductance, and thermal analysis. A square planar structure was proposed for the complexes

Criteria of existence and stability of an n-coupled system of generalized Sturm-Liouville equations with a modified ABC fractional derivative and an application to the SEIR influenza epidemic model

The primary objective of this study was to explore the behavior of an n-coupled system of generalized Sturm-Liouville (GSL) and Langevin equations under a modified ABC fractional derivative. We aimed to analyze the dynamics of the system and gain insights into how this operator influences the conditions for the existence and uniqueness of solutions. We established the existence and uniqueness of solutions by employing the Banach contraction principle and Leray-Schauder's alternative fixed-point theorem. We also investigated the Hyers-Ulam stability of the system. This analysis allows us to understand the stability properties of the solutions and evaluate their sensitivity to perturbations. Furthermore, we employed Lagrange's interpolation polynomials to produce a numerical scheme for the influenza epidemic model. By combining theoretical analysis, mathematical principles, and numerical simulations, this study contributes to enriching our understanding of the behavior of the system and offers insights into its dynamics and practical applications in epidemiology

High-Pressure Metal-Free Catalyzed One-Pot Two-Component Synthetic Approach for New 5-Arylazopyrazolo[3,4-b]Pyridine Derivatives

An appropriate and efficient Q-tube-assisted ammonium acetate-mediated protocol for the assembly of the hitherto unreported 5-arylazopyrazolo[3,4-b]pyridines was demonstrated. This methodology comprises the cyclocondensation reaction of 5-amino-2-phenyl-4H-pyrazol-3-one with an assortment of arylhydrazonals in an NH$_4$OAc/AcOH buffer solution operating a Q-tube reactor. This versatile protocol exhibited several outstanding merits: easy work-up, mild conditions, scalability, broad substrate scope, safety (the Q-tube kit is simply for pressing and sealing), and a high atom economy. Consequently, performing such reactions under elevated pressures and utilizing the Q-tube reactor seemed preferable for achieving the required products in comparison to the conventional conditions. Diverse spectroscopic methods and X-ray single-crystal techniques were applied to confirm the proposed structure of the targeted compounds

Reactivity of N-substituted alkenylidene hydrazinecarbothioamides toward tetracyanoethylene, an efficient synthesis stereoselective 1,3-thiazole compounds

The reaction between N-substituted alkenylidene hydrazinecarbothioamides and two molar amounts of tetracyanoethylene (TCNE) in anhydrous THF at room temperature without using any catalyst affords (Z)-4-amino-3-((Z)substituted amino)-2-(substituted imino)-2,3-dihydrothiazole-5-carbonitriles and (Z)-(4-amino-5-cyano-thiazol-2(3H)-ylidene)carbonhydrazonoyl dicyanides. Rationales for these transformations are presented. The structures of the obtained products were confirmed via single-crystal X-ray analyses. Graphic Here, we synthesize (Z)-4-amino-3-amino-2-imino-2,3-dihydrothiazole-5-carbonitriles and (Z)-(4-amino-5-cyano-thiazol-2(3H)-ylidene)carbonhydrazonoyl dicyanides from the reaction of N-substituted alkenylidene hydrazinecarbothioamides with (TCNE) in anhydrous THF at room temperature without using any catalyst. [GRAPHICS] .Peer reviewe