133 research outputs found

    Study of effective calculation operation implementation remaining multi-bit numbers division on FPGA

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    The rapid enhanced in the fields of the computers that leads to rapid breaking for ciphering algorithms and for these reasons most of ciphering algorithm tried to used multidigit for ciphering texts or images. Using the multidigit will increase the safety of information and protected it from supercomputer from breaking the ciphering algorithms. The current information systems employ operations on finite fields of various structures (for example, cryptographic systems). In this instance, it's common to have to deal with enormous numbers (128 bits or more). The proposed operation of discovering the remainder of the division of multidigit numbers will considerably improve the speed of such systems if implemented

    Design and implementation 4x4 Network on Chip (NoC) using FPGA

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    The Network on chip is one of the most crucial in the development of the networks and routers in new days due to the improvement that make through way of sending huge packets of data and technology and protocol that used for sending the packets between IP cores. Also the NoC is removed the old ways of technique and protocols of sending packets through routers. The NoC is the most enhanced and efficient in working in parallel ways. Hence, Field Program Gate Array (FPGA) is used in the designing of router that its architecture depending on the NoC. The research proposed in this paper proposed 4x4 nodes router with mesh network that support two dimensional architecture. A real time test is used for experimental through FPGA and the test verified efficient packets transporting via two array buffers that integrated in the proposed router architecture

    Polyphenols content and antioxidant power of fruits and leaves of Juniperus phoenicea L. From Tounfite (Morocco)

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    The natural antioxidants have attracted considerable attention of researchers because of their beneficial roles in human health. In the framework of the development of new antioxidants from natural sources, we are interested in this work in studying the phenolic compounds and evaluating the antioxidant properties of Juniperus phoenicea L. leaves and fruits collected in the mountains of Eastern High-Atlas (Tounfite). The phytochemical screening has allowed highlighting the existence of polyphenols, tannins, flavonoids, sterols and triterpenes, and oses and holosides in both studied samples. Mucilages are also present in these samples but in small quantities, while alkaloids and saponins are entirely absent. Extracts from leaves and fruits have been obtained by different extraction solvents: water, methanol, chloroform, ethyl acetate and n-butanol. The contents of total phenols and flavonoids were evaluated using gallic acid and quercetin as standard respectively. The ethyl acetate extracts of the leaves and fruits contain high levels of total phenolic estimated 2,91mg/g and 5,35mg/g equivalent of gallic acid (GAE) respectively. As for the flavonoid content, the ethyl acetate extracts have also reached the increased levels 11,82mg/g and 2,66mg/g equivalent of quercetin (QE). The antioxidant activities by DPPH test were quantified by spectrophotometry; the results showed that the ethyl acetate extracts from the leaves and fruits exhibit an antioxidant activity with inhibitory concentrations 50% (IC50) of 94,4μg/ml and 185,83μg/ml respectively compared to that of vitamin C (47,76μg/ml). The antioxidant test allowed concluding that the leaves and fruits have a strong anti-radical activity that was assumed to be related closely to the content of polyphenols, which are generally very good antioxidants and that the leaves show a higher activity than fruits.

    Оценка надежности высоконадежных систем с учетом ЗИП

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    Предложены приближенные верхние и нижние оценки коэффициента готовности высоконадежной восстанавливаемой системы со структурной избыточностью. Полученные расчетные соотношения могут использоваться для оценки надежности высоконадежных систем с учетом различных стратегий пополнения ЗИП

    Order-of-magnitude speedup for steady states and traveling waves via Stokes preconditioning in Channelflow and Openpipeflow

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    Steady states and traveling waves play a fundamental role in understanding hydrodynamic problems. Even when unstable, these states provide the bifurcation-theoretic explanation for the origin of the observed states. In turbulent wall-bounded shear flows, these states have been hypothesized to be saddle points organizing the trajectories within a chaotic attractor. These states must be computed with Newton's method or one of its generalizations, since time-integration cannot converge to unstable equilibria. The bottleneck is the solution of linear systems involving the Jacobian of the Navier-Stokes or Boussinesq equations. Originally such computations were carried out by constructing and directly inverting the Jacobian, but this is unfeasible for the matrices arising from three-dimensional hydrodynamic configurations in large domains. A popular method is to seek states that are invariant under numerical time integration. Surprisingly, equilibria may also be found by seeking flows that are invariant under a single very large Backwards-Euler Forwards-Euler timestep. We show that this method, called Stokes preconditioning, is 10 to 50 times faster at computing steady states in plane Couette flow and traveling waves in pipe flow. Moreover, it can be carried out using Channelflow (by Gibson) and Openpipeflow (by Willis) without any changes to these popular spectral codes. We explain the convergence rate as a function of the integration period and Reynolds number by computing the full spectra of the operators corresponding to the Jacobians of both methods.Comment: in Computational Modelling of Bifurcations and Instabilities in Fluid Dynamics, ed. Alexander Gelfgat (Springer, 2018

    Competitiveness and communication for effective inoculation byRhizobium, Bradyrhizobium and vesicular-arbuscular mycorrhiza fungi

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    After a short summary on the ecology and rhizosphere biology of symbiotic bacteria and vesicular-arbuscular (VA) mycorrhiza fungi and their application as microbial inocula, results on competitiveness and communication are summarized. Stress factors such as high temperature, low soil pH, aluminium concentrations and phytoalexins produced by the host plants were studied withRhizobium leguminosarum bv.phaseoli andRhizobium tropici onPhaseolus beans. Quantitative data for competitiveness were obtained by usinggus + (glucoronidase) labelled strains, which produce blue-coloured nodules. ForPhaseolus-nodulating rhizobia, a group specific DNA probe was also developed, which did not hybridize with more than 20 other common soil and rhizosphere bacteria. Results from several laboratories contributing to knowledge of signal exchange and communication in theRhizobium/Bradyrhizobium legume system are summarized in a new scheme, including also defense reactions at the early stages of legume nodule initiation. Stimulating effects of flavonoids on germination and growth of VA mycorrhiza fungi were also found. A constitutive antifungal compound in pea roots, -isoxazolinonyl-alanine, was characterized

    Optimizing Taq Polymerase Concentration for Improved Signal-to-Noise in the Broad Range Detection of Low Abundance Bacteria

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    BACKGROUND:PCR in principle can detect a single target molecule in a reaction mixture. Contaminating bacterial DNA in reagents creates a practical limit on the use of PCR to detect dilute bacterial DNA in environmental or public health samples. The most pernicious source of contamination is microbial DNA in DNA polymerase preparations. Importantly, all commercial Taq polymerase preparations inevitably contain contaminating microbial DNA. Removal of DNA from an enzyme preparation is problematical. METHODOLOGY/PRINCIPAL FINDINGS:This report demonstrates that the background of contaminating DNA detected by quantitative PCR with broad host range primers can be decreased greater than 10-fold through the simple expedient of Taq enzyme dilution, without altering detection of target microbes in samples. The general method is: For any thermostable polymerase used for high-sensitivity detection, do a dilution series of the polymerase crossed with a dilution series of DNA or bacteria that work well with the test primers. For further work use the concentration of polymerase that gave the least signal in its negative control (H(2)O) while also not changing the threshold cycle for dilutions of spiked DNA or bacteria compared to higher concentrations of Taq polymerase. CONCLUSIONS/SIGNIFICANCE:It is clear from the studies shown in this report that a straightforward procedure of optimizing the Taq polymerase concentration achieved "treatment-free" attenuation of interference by contaminating bacterial DNA in Taq polymerase preparations. This procedure should facilitate detection and quantification with broad host range primers of a small number of bona fide bacteria (as few as one) in a sample

    Highly variable response to cytotoxic chemotherapy in carcinoma-associated fibroblasts (CAFs) from lung and breast

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    <p>Abstract</p> <p>Background</p> <p>Carcinoma-associated fibroblasts (CAFs) can promote carcinogenesis and tumor progression. Only limited data on the response of CAFs to chemotherapy and their potential impact on therapy outcome are available. This study was undertaken to analyze the influence of chemotherapy on carcinoma-associated fibroblasts (CAFs) <it>in vitro </it>and <it>in vivo</it>.</p> <p>Methods</p> <p>The <it>in vivo </it>response of stromal cells to chemotherapy was investigated in 22 neoadjuvant treated breast tumors on tissue sections before and after chemotherapy. Response to chemotherapy was analyzed <it>in vitro </it>in primary cultures of isolated CAFs from 28 human lung and 9 breast cancer tissues. The response was correlated to <it>Mdm2</it>, <it>ERCC1 </it>and <it>TP53 </it>polymorphisms and <it>TP53 </it>mutation status. Additionally, the cytotoxic effects were evaluated in an <it>ex vivo </it>experiment using cultured tissue slices from 16 lung and 17 breast cancer specimens.</p> <p>Results</p> <p>Nine of 22 tumors showed a therapy-dependent reduction of stromal activity. Pathological response of tumor or stroma cells did not correlate with clinical response. Isolated CAFs showed little sensitivity to paclitaxel. In contrast, sensitivity of CAFs to cisplatinum was highly variable with a GI50 ranging from 2.8 to 29.0 μM which is comparable to the range observed in tumor cell lines. No somatic <it>TP53 </it>mutation was detected in any of the 28 CAFs from lung cancer tissue. In addition, response to cisplatinum was not significantly associated with the genotype of <it>TP53 </it>nor <it>Mdm2 </it>and <it>ERCC1 </it>polymorphisms. However, we observed a non-significant trend towards decreased sensitivity in the presence of <it>TP53 </it>variant genotype. In contrast to the results obtained in isolated cell culture, in tissue slice culture breast cancer CAFs responded to paclitaxel within their microenvironment in the majority of cases (9/14). The opposite was observed in lung cancer tissues: only few CAFs were sensitive to cisplatinum within their microenvironment (2/15) whereas a higher proportion responded to cisplatinum in isolated culture.</p> <p>Conclusion</p> <p>Similar to cancer cells, CAF response to chemotherapy is highly variable. Beside significant individual/intrinsic differences the sensitivity of CAFs seems to depend also on the cancer type as well as the microenvironment.</p
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