420 research outputs found

    Convenient Synthesis of Some New Bi-heterocycles conataining 3-Aminoquinazolin-4(3H)-one and 1,2,4-Triazole moieties

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    Dicarboxylic acids, thiosemicarbazides and methylanthranilate reacted to give methyl-2-(3-(5-mercapto-4-s-1,2,4-triazol-3-yl)-3-oxoalkylamino)benzoates 4. The laters, cyclized with hydrazine hydrate to give 3-amino-2-((5-mercapto-4 substitued-1,2,4-triazol-3-yl)alkyl)quinazolin-4(3H)-ones 5 which expected to have biological effects

    Syntactic model reduction for hardware verification

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    Microelectronics systems become more and more complex, making the detection of errors extremely difficult. Model checking, as a formal hardware verification technique, can potentially catch subtle hardware design errors. It is used to automatically verify temporal properties on finite state systems. However, model checking tools suffer from the state explosion problem; when the number of states representing the program under verification grows exponentially. state explosion problem. The main idea of model reduction is to suppress the techniques that involve both approaches can greatly reduce the design under techniques in which, variables not influencing the property's variables are removed and the values domains of state variables in the system model are values according to their dependency to the property to be verified. After the above procedures are done, the state space of the reduced program is smaller than that of the original one, while the correctness of the properties are preserved. We have developed a tool called SynAbs which accepts a subset of the Verilog hardware description language and universally quantified computation tree logic (CTL) temporal properties, and generates a reduced Verilog code which can be fed into a CTL model checker. We have successfully applied our tool on the verification of a number of simple Verilog programs

    Sacrococcygeal teratoma excision: a vertical rather than transverse wound closure

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    Background: The chevron incision has been the standard approach for sacrococcygeal teratoma (SCT) excision. Here, we are reporting our experience of shifting to the vertical posterior sagittal approach.Patients and methods: During the period 2011 through 2016, we operated on 17 (16 female and one male) cases of SCT. Their age at presentation ranged from day 1 to 26 months (mean=4.8 months, median=2 months). The chevron incision was used in five, whereas the vertical posterior sagittal approach was used in 12 patients.Results: In this series, we had one case of perioperative mortality, in addition to another case of perineal wound disruption (in the group of vertical wound closure), which was managed conservatively (to heal by secondary intention) with a very satisfactory hidden scar at 6-month follow-up. Overall, we did not find the vertical approach to add any extra limitations to the surgical exposure or dissection; meanwhile, it provided a well-recognized cosmetic advantage.Conclusion: The vertical posterior sagittal approach for excision of SCT is both feasible and advantageous in terms of the cosmetic outcome. It provides a well-hidden scar in the natal cleft and preserves normal contouring of the buttocks.Keywords: buttock, cosmesis, posterior sagittal, reconstruction, sacrococcygeal teratom

    Invasive fungal infections and patients with malignancies in upper Egypt

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    The incidence of invasive fungal infections has increased considerably in recent years. The aim of this study was to present a suitable early diagnostic procedure in immune compromised patients, using detection of fungal infection of urine samples collected from 33 patients with malignancies (from 2-89 years old), during the period from December 2012 to February 2014, from South Egypt. Fifty-three fungal species representing 14 genera were collected during this investigation from urine samples on Sabouraoud’s Dextrose Chloramphenicol Agar (46 species and 12 genera) and Rose Bengal Chloramphenicol Agar media (41 species and 11 genera). Aspergillus (16 species), Penicillium (14 species), Yeasts (5 species) and Cladosporium (5 species) contributed the broadest spectra of species in all samples tested on two types of media used. Other species were represented by 13 species belonging to 10 genera. The results indicate that immune compromised patient is a suitable habitat for the growth and sporulation of different groups of fungi, both saprophytic and pathogenic. A variety of types of filamentous fungi were obtained from malignancies patients. Immunosuppressant patient’s exposure for fungal infection so should be in especial care from food, drinking and air. Published by the International journal of Microbiology and Mycology (IJMM

    Formal verification of analog and mixed signal designs: A survey

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    Analog and mixed signal (AMS) designs are an important part of embedded systems that link digital designs to the analog world. Due to challenges associated with its verification process, AMS designs require a considerable portion of the total design cycle time. In contrast to digital designs, the verification of AMS systems is a challenging task that requires lots of expertise and deep understanding of their behavior. Researchers started lately studying the applicability of formal methods for the verification of AMS systems as a way to tackle the limitations of conventional verification methods like simulation. This paper surveys research activities in the formal verification of AMS designs as well as compares the different proposed approaches

    Towards Enhancing Analog Circuits Sizing Using SMT-based Techniques

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    ABSTRACT This paper presents an approach for enhancing analog circuit sizing using Satisfiability Modulo Theory (SMT). The circuit sizing problem is encoded using nonlinear constraints. An SMT-based algorithm exhaustively explores the design space, where the biasing-level design variables are conservatively tracked using a collection of hyperrectangles. The device dimensions are then determined by accurately relating biasing to geometry-level design parameters. We demonstrate the feasibility and efficiency of the proposed methodology on a two-stage amplifier and a folded cascode amplifier. Experimental results show that our approach can achieve higher quality in analog synthesis and unrivaled coverage of the design space

    Using Stochastic Differential Equation for Verification of Noise in Analog/RF Circuits

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    Today’s analog/RF design and verification face significant challenges due to circuit complexity, process variations and short market windows. In particular, the influence of technology parameters on circuits, and the issues related to noise modeling and verification still remain a priority for many applications. Noise could be due to unwanted interaction between the circuit elements or it could be inherited from the circuit elements. In addition, manufacturing disparity influence the characteristic behavior of the manufactured circuits. In this paper, we propose a methodology for modeling and verification of analog/RF designs in the presence of noise and process variations. Our approach is based on modeling the designs using stochastic differential equations (SDE) that will allow us to incorporate the statistical nature of noise. We also integrate the device variation due to 0.18μ m fabrication process in an SDE based simulation framework for monitoring properties of interest in order to quickly detect errors. Our approach is illustrated on nonlinear Tunnel-Diode and a Colpitts oscillator circuits

    A multi-band MIMO antenna system with coupled-fed modified rectangular patch elements for 5G systems

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    A four-port multiple input multiple output (MIMO) antenna system constructed of four compact dual-band (38/60 GHz) microstrip patch antennas is proposed for 5G mobile applications. Each individual element is optimized to achieve the desired performance of the overall MIMO system. Numerical and experimental investigations are achieved to assess the performance of both the single-element antenna and the four-port MIMO antenna system. It is shown that the simulation results agree with the experimental measurements, and both show good performance of the proposed MIMO antenna system. The bandwidths achieved around 38 GHz and 60 GHz are about 2 GHz and 3.2 GHz, respectively. The performance of the MIMO antenna system including the return loss at each antenna port and the coupling coefficients between the different ports are investigated. The radiation patterns produced when each port is excited alone are shown to be suitable for spatial diversity scheme. They have a high radiation efficiency exhibited by a balloon-like shaped radiation pattern for both the upper and lower frequency bands. It is shown that the envelope correlation coefficient (ECC) and the diversity gain (DG) are suitable for performance for the targeted 5G bands.</p

    Effect of different concentrations of chitosan coating on storage life and quality characteristics of Papaya (Carica Papaya L.)

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    Mature green stage of papaya fruits were treated with different concentrations of chitosan at 0, 0.5, 0.75 and 1%, and stored at 13±1 °C for 28 days to study the effect of these concentrations on the storage life and maintaining quality of papaya. Chitosan concentrations 0.75 and 1% showed the best control effect on decay compared with 0% (Control) and 0.5%. At 0.75 and 1% of chitosan, flesh firmness maintained resulted in prolonging in storage life of 28 and 26 days compared with 21 and 19 days, respectively for 0.5 and 0%. Furthermore, they were significantly decreased the weight loss of fruit. All of the treatments inhibited increase of soluble solid contents and pH values of pulp fruits after 21 days of storage at 13 ± 1°C. Titratable acidity and ascorbic acid were higher for coated fruits (0.5, 0.75 and 1%) compared with uncoated fruits. Concern treatments of chitosan at 0.75 and 1% improve papaya fruit quality and resistance to decay
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