4,299 research outputs found

    A novel methodology for the concurrent test of partial and dynamically reconfigurable SRAM-based FPGAs

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    This poster presents the first truly non-intrusive structural concurrent test approach, with the objective of testing partially and dynamically reconfigurable SRAM-based FPGAs without disturbing their operation. This is accomplished by using a new methodology to carry out the replication of active Configurable Logic Blocks (CLBs), i.e. CLBs that are part of an implemented function that is actually being used by the system, releasing it to be tested in a way that is completely transparent to the system

    Run-time management of logic resources on reconfigurable systems

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    Dynamically reconfigurable systems based on partialand dynamically reconfigurable FPGAs may have theirfunctionality partially modified at run-time withoutstopping the operation of the whole system.The efficient management of the logic space availableis one of the biggest problems faced by these systems.When the sequence of reconfigurations to be performed isnot predictable, resource allocation decisions have to bemade on-line. A rearrangement may be necessary to getenough contiguous space to implement incomingfunctions, avoiding the spreading of their components andthe resulting degradation of system performance.A new software tool that helps to handle the problemsposed by the consecutive reconfiguration of the same logicspace is presented in this paper. This tool uses a novel on--line rearrangement procedure to solve fragmentationproblems and to rearrange the logic space in a waycompletely transparent to the applications currentlyrunnin

    Programmable logic devices: a test approach for the Input / Output blocks and Pad-to-Pin interconnections

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    Dynamically reconfigurable systems based on partial and dynamically reconfigurable FPGAs may have their functionality partially modified at run-time without stopping the operation of the whole system. The efficient management of the logic space available is one of the biggest problems faced by these systems. When the sequence of reconfigurations to be performed is not predictable, resource allocation decisions have to be made on-line. A rearrangement may be necessary to get enough contiguous space to implement incoming functions, avoiding the spreading of their components and the resulting degradation of system performance.A new software tool that helps to handle the problems posed by the consecutive reconfiguration of the same logic space is presented in this paper. This tool uses a novel on-line rearrangement procedure to solve fragmentation problems and to rearrange the logic space in a way completely transparent to the applications currently running

    Antimicrobial activity of the essential oils of Dittrichia viscosa subsp viscosa on Helicobacter pylori

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    Dittrichia viscosa subsp. viscosa (Compositae) is found on edges, wood clearings and in waste places of the Iberian Peninsula. Aerial parts of D. viscosa were collected at flowering phase in September-October 2001 around Lisbon, Portugal and the essential oils isolated by hydro-distillation for 4 h using a Clevenger-type apparatus. The oils were analyzed by gas chromatography and gas chromatography-mass spectrometry. Preliminary examination of the essential oils allowed the identification of 32 components. Only four components reached percentages over 5%: fokienol (11.8%), T-muurorol (7.9%), (E)-nerolidol (5.5%) and delta-cadinene (5.0%). The essential oils were tested against Helicobacterpylori and Listeria monocytogenes. Essential oils did not have antimicrobial activity against L. monocytogenes. The essential oil at 0.88 to 22.22 mu g.ml(-1) did not inhibit the growth of H. pylori, affected the growth slightly at 44.40 mu g.ml(-1), and completely inhibited the growth at 88.80 to 133.20 mu g.ml(-1) Results show that use of D. viscosa essential oil in the treatment of gastric disorders caused by H. pylori can be effective

    Langevin theory of absorbing phase transitions with a conserved magnitude

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    The recently proposed Langevin equation, aimed to capture the relevant critical features of stochastic sandpiles, and other self-organizing systems is studied numerically. This equation is similar to the Reggeon field theory, describing generic systems with absorbing states, but it is coupled linearly to a second conserved and static (non-diffusive) field. It has been claimed to represent a new universality class, including different discrete models: the Manna as well as other sandpiles, reaction-diffusion systems, etc. In order to integrate the equation, and surpass the difficulties associated with its singular noise, we follow a numerical technique introduced by Dickman. Our results coincide remarkably well with those of discrete models claimed to belong to this universality class, in one, two, and three dimensions. This provides a strong backing for the Langevin theory of stochastic sandpiles, and to the very existence of this new, yet meagerly understood, universality class.Comment: 4 pages, 3 eps figs, submitted to PR

    Synbiobacther: engineering "therapeutic" bacteria

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    Over 1.2 million persons will be diagnosed with breast cancer worldwide per year. Ultrasound treatment is not always successful, as sometimes it just heats the tumour without destroying it. If it would be possible to link this treatment with the expression/release of a therapeutic agent, the joint effect could be more effective. Some efforts have been made in this direction, although to date the results have not been very encouraging; potential reasons include lack of precise control over administration of the drug. Therefore, the purpose of this project is to overcome this barrier through the use of synthetic biology strategies to engineer a model bacterium to trigger release of a therapeutic agent concurrent with ultrasound treatment. The specific plan is to engineer the existing heat shock response machinery from Escherichia coli to trigger the synthesis and release of curcumin in situ. Curcumin has an anti-proliferative capability and an anticarcinogenic and chemopreventive effect. Although curcumin has some attractive properties as a novel drug, it has a poor bioavailability, requiring repetitive oral doses to achieve sufficient concentration inside the cells for therapeutic activity. Hence, the possibility of synthesizing curcumin in situ in a controlled way, as proposed in this project, provides a powerful alternative.info:eu-repo/semantics/publishedVersio

    Injectable and tunable hyaluronic acid hydrogels releasing chemotactic and angiogenic growth factors for endodontic regeneration

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    Bioengineered soft tissues on any meaningful scale or complexity must incorporate aspects of the functional tissue, namely a vasculature, providing cells oxygen and nutrients critical for their survival. However, the ability of tissue engineering strategies to promote a fast revascularization is critically limited. Particularly in endodontic regenerative therapies, the complicated anatomy of the root canal system, and the narrow apical access limit the supply of new blood vessels and pulp tissue ingrowth. Here we characterize the viscoelastic and microstructural properties of a class of injectable hyaluronic acid (HA) hydrogels formed in situ, reinforced with cellulose nanocrystals (CNCs) and enriched with platelet lysate (PL), and test its ability to promote cells recruitment and proangiogenic activity in vitro. The incorporation of CNCs enhanced the stability of the materials against hydrolytic and enzymatic degradation. Moreover, the release of the chemotactic and pro-angiogenic growth factors (GFs) (PDGF and VEGF) from the PL-laden hydrogels showed an improved sustained profile proportional to the amount of incorporated CNCs. The PL-laden hydrogels exhibited preferential supportive properties of encapsulated human dental pulp cells (hDPCs) in in vitro culture conditions. Finally, PL-laden hydrogels stimulated chemotactic and pro-angiogenic activity by promoting hDPCs recruitment and cell sprouting in hDPCs/human umbilical vein endothelial cell co-cultures in vitro, and in an ex vivo model. These results support the use of the combined system as a scaffold for GFs delivery and cells recruitment, thereby exhibiting great clinical potential in treating injuries in vascularized tissues.RECOGNIZE project (UTAP-ICDT/CTM-BIO/0023/2014), project NORTE-01-0145-FEDER-000021. R.M.A. Domingues acknowledges FCT for SFRH/BPD/112459/2015. P.S. Babo acknowledges the project FOOD4CELLS (PTDC/CTM-BIO/4706/2014-POCI-01-0145-FEDER 016716) for his post-doc grantinfo:eu-repo/semantics/publishedVersio

    The Si + SO2 collision and an extended network of neutral–neutral reactions between silicon and sulphur bearing species

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    International audienceThe Si + SO2 reaction is investigated to verify its impact on the abundances of molecules with astrochemical interest, such as SiS, SiO, SO, and others. According to our results Si(3P) and SO2 react barrierlessly yielding only the monoxides SO and SiO as products. No favourable pathway has been found leading to other products, and this reaction should not contribute to SiS abundance. Furthermore, it is predicted that SiS is stable in collisions with O2, and that S(3P) + SiO2 and O(3P)+OSiS will also produce SO + SiO. Using these results and gathering further experimental and computational data from the literature, we provide an extended network of neutral-neutral reactions involving Si- and S-bearing molecules. The effects of these reactions were examined in a protostellar shock model, using the NAUTILUS gas-grain code. This consisted in simulating the physicochemical conditions of a shocked gas evolving from (i) primeval cold core, (ii) the shock region itself, (iii) and finally the gas bulk conditions after the passage of the shock. Emphasizing on the cloud ages and including systematically these chemical reactions, we found that [SiS/H2] can be of the order of ~10-8 in shocks that evolves from clouds of t = 1 × 106 yr, whose values are mostly affected by the SiS + O \longrightarrowSiO + S reaction. Perspectives on further models along with observations are discussed in the context of sources harbouring molecular outflows
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