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In a reconfigurable manufacturing scenario, control system design needs innovative approaches to face the rapid changes in hardware and software modules. The control system should be able to automatically tune its parameters to enhance machine performances and dynamically adapt to different control objectives (e.g., minimize control efforts or maximize tracking performances) while preserving at the same time stability and robustness properties. In this paper, a robust control system for permanent magnet synchronous motors (PMSMs), together with an online self-tuning method, is presented. In particular, a robust discrete-time variable structure control (VSC) has been designed. A heuristic bio-inspired approach has been then implemented on a digital signal processor (DSP) to find the VSC parameter set which minimizes a specific objective function each time a novel speed reference is provided. Experimental results on a PMSM motor show the effectiveness of the proposed controller and tuning method, with noticeable improvements with respect to the original manufacturer-designed controller.

Mobile and pervasive computing enabled a new realm of possibilities into the indoor positioning domain. Although many candidate technologies have been proposed, no one can still adapt to every use case. A case centered design and the implementation of the solution within the specific domain is the current research trend. With the rise of Bluetooth Low Energy (BLE) Beacons, i.e., platforms used to interact digitally with the real world, more standard positioning solutions are emerging in different contexts. However the reachable positioning accuracy with this technology is still unacceptable for some real applications (e.g., in the healthcare sector or the emergency management). In this paper, an hybrid localization application coupling a real time model based Pedestrian Dead Reckoning (PDR) technique and the analysis of the Received Signal Strength Indicator (RSSI) of BLE beacons is proposed. In particular, the smartphone application is composed by three main real time threads: a model based step length estimation, heading determination and the fusion of beacon information to reset the position and the drift error of the PDR. In order to give soundness to our approach we firstly validated the step length smartphone app with a stereo-photogrammetric system. The whole proposed solution was then tested on fifteen healthy subjects.

We have recently shown that in humans submaximal mouth opening associated with partial masticatory movements for 10 min is followed by a small but significant and prolonged reduction of blood pressure and heart rate. We here report the effects of a fixed mouth opener. In 22 seated normotensive volunteers the effect on blood pressure and heart rate was studied in randomized order after fixed mandibular extension and after a control procedure consisting in keeping a stick between the incisor teeth (both for 10 min). Automated recordings every 10 min were done for 40 min before and 120 min following the procedure. Two-way ANOVA for repeated measures on absolute values (actual recordings) and on changes from baseline revealed that, compared to controls, systolic, diastolic and mean blood pressure and heart rate were significantly lower after mandibular extension. Compared to controls, mandibular extension induced an average blood pressure drop of 2.88 mmHg (systolic), 2.55 mmHg (diastolic) and 2.42 mmHg (mean) over the entire observation period. The average decline over the central part of the observation period (30th to 80th min) was, respectively, of 3.62, 3.70 and 3.61 mmHg. The decrements of heart rate were of 2.11 and 2.66 beats per min. All these differences were statistically significant. The hypotensive and bradycardic responses persisted for 70–120 min. This study shows that, in normotensives, a single fixed submaximal mouth opening for 10 min is followed by prolonged albeit small reductions of blood pressure and heart rate.

The enzyme nitric oxide synthase (NOS) oxidizes L-arginine to NO and citrulline. In this work, we characterise the NOS from the cyanobacteria Synechococcus PCC 7335 (SyNOS). SyNOS possesses a canonical mammalian NOS architecture consisting of oxygenase and reductase domains. In addition, SyNOS possesses an unusual globin domain at the N-terminus. Recombinant SyNOS expressed in bacteria is active, and its activity is suppressed by the NOS inhibitor L-NAME. SyNOS allows E. coli to grow in minimum media containing L-arginine as the sole N source, and has a higher growth rate during N deficiency. SyNOS is expressed in Synechococcus PCC 7335 where NO generation is dependent on L-arginine concentration. The growth of Synechococcus is dramatically inhibited by L-NAME, suggesting that SyNOS is essential for this cyanobacterium. Addition of arginine in Synechococcus increases the phycoerythrin content, an N reservoir. The role of the novel globin domain in SyNOS is discussed as an evolutionary advantage, conferring new functional capabilities for N metabolism. Fil: Correa Aragunde, Maria Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina. Universidad Nacional de Mar del Plata; Argentina Fil: Foresi, Noelia Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina. Universidad Nacional de Mar del Plata; Argentina Fil: del Castello, Fiorella Paola. Universidad Nacional de Mar del Plata; Argentina Fil: Lamattina, Lorenzo. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina

A variety of realistic economic considerations make jump-diffusion models of interest rate dynamics an appealing modeling choice to price interest-rate contingent claims. However, exact closed-form solutions for bond prices when interest rates follow a mixed jump-diffusion process have proved very hard to derive. This paper puts forward two new models of interest-rate dynamics that combine infrequent, discrete changes in the interest-rate level, modeled as a jump process, with short-lived, mean reverting shocks, modeled as a diffusion process. The two models differ in the way jumps affect the central tendency of interest rates; in one case shocks are temporary, in the other shocks are permanent. We derive exact closed-form solutions for the price of a discount bond and computationally tractable schemes to price bond options.

Inhaled furosemide (frusemide), a loop diuretic which inhibits the Na+/2Cl−/K+ cotransport system, has been shown to inhibit asthma provoked by several bronchial stimuli known to induce mediator release from inflammatory cells. Although other loop diuretics with greater diuretic potency (e.g. bumetanide, piretanide and torasemide) have been tested, furosemide provides the widest and most effective antiasthma activity. Inhaled acetazolamide, a selective inhibitor of carbonic anhydrase, may have a similar protective profile. The relative antiasthma activity of these agents seems to be unrelated to their diuretic potency, but is likely to be linked to their pharmacokinetic characteristics. The underlying mechanisms of antiasthma activity are probably a reduction of mediator release from inflammatory cells and a modulation of bronchocon-striction mediated by sensory nerve activation. Whether this observation will lead to the development of a new class of antiasthma compounds or will be a research tool for the study of asthma pathophysiology remains to be determined.

Cough is a protective mechanism and an important symptom of many respiratory diseases. When coughing is only an annoying reflex and produces no mucus clearance, inducing fatigue or exhaustion for patients and worsening their pathological condition, antitussive drugs may be indicated. In this study we evaluated the efficacy and safety of moguisteine, a new antitussive drug with a peripheral mechanism of action, in a population of 124 adult patients with persistent cough associated with various respiratory disorders. Obstructive chronic bronchitis, reported in about 50% of the study population, was the most frequent underlying diagnosis. We conducted a randomised single-blind short term treatment trial in 7 centres, comparing moguisteine (3 doses of 200mg, over 2 days) to dextromethorphan (3 doses of 30mg, over 2 days). The primary efficacy variable was the percentage reduction in the audio tape-recorded number of coughs during a 6-hour period in the morning after the last dose of the study drug versus a 6-hour recording at baseline. Patients’ subjectively assessed visual analogue scale (VAS) scores of cough frequency and cough troublesomeness at night and during the morning were considered as secondary efficacy variables. Safety was assessed by means of routine clinical laboratory tests and adverse event monitoring. The postdrug percentage reduction in the number of coughs approached 30% on either drug. VAS scores of cough frequency and cough troublesomeness showed remarkable reductions in both groups, without any noteworthy difference between treatments. Possible or probable drug-related adverse events were reported in 3 of 61 patients on moguisteine (1 heartburn, 1 gastric pain, 1 diarrhoea) and in 4 of 63 patients on dextromethorphan (1 rhinitis and slight decrease of white blood cell count, 1 syncope, 1 gastric discomfort, 1 diarrhoea). Treatment discontinuation was necessary only for 1 patient, who had a syncope after the first dose of dextromethorphan. Our results indicate that treatment with moguisteine rapidly induces substantial cough relief and that it is well tolerated and as effective as dextromethorphan.

Confinement of light to small volumes has important implications for optical emission properties: it changes the probability of spontaneous emission from atoms, allowing both enhancement and inhibition. In photonic-bandgap (PBG) materials1,2,3,4 (also known as photonic crystals), light can be confined within a volume of the order of (λ/2n)3, where λ is the emission wavelength and n the refractive index of the material, by scattering from a periodic array of scattering centres. Until recently5,6, the properties of two- and three-dimensional PBG structures have been measured only at microwave frequencies. Because the optical bandgap scales with the period of the scattering centres, feature sizes of around 100 nm are needed for manipulation of light at the infrared wavelength (1.54 µm) used for optical communications. Fabricating features this small requires the use of electron-beam or X-ray lithography. Here we report measurements of microcavity resonances in PBG structures integrated directly into a sub-micrometre-scale silicon waveguide. The microcavity has a resonance at a wavelength of 1.56 µm, a quality factor of 265 and a modal volume of 0.055 µm3. This level of integration might lead to new photonic chip architectures and devices, such as zero-threshold microlasers, filters and signal routers.

The path for silicon materials development has been charted. By the year 2010 we will have fabricated integrated circuit chips containing 109 transistors with 40 Å thick gate oxides and 1000 Å minimum feature sizes running at 4 GHz clock speeds. It is conceivable that incremental advances on the current chip architecture will satisfy the required materials and process improvements. The interconnection problem is the only challenge without a proposed solution. The signal propagation delay between devices is now longer than the individual device gate delay. The resistance and capacitance associated with fine line Al interconnects limit speed and increase power consumption and crosstalk. High power line drivers are limited by the reliability constraint of electromigration. There is no current paradigm for 4 GHz, electronic clock distribution. Optical interconnection can remove the electronic transmission bandwidth limit. The main challenge is development of a silicon-compatible, microphotonic technology.Rare earth doping has provided a means of sharp-line electroluminescence from silicon at λ = 1.54 μm. Silicon's high index of refraction and low absorption in the near infrared yield an ideal optical waveguide. As with microelectronics, the silicon / silicon-dioxide materials system allows high levels of integration and functionality. The applications of silicon materials to light emission (Si:Er), optical waveguides (Si/SiO2), photonic switching (Si/SiO2) and photon detection (SiGe) are reviewed. These developments are discussed in the context of systems applications to communications and computation.

Photonic integrated circuits in silicon require waveguiding through a material compatible with silicon VLSI technology. Polysilicon (polySi), with a high index of refraction compared to SiO2 and air, is an ideal candidate for use in silicon optical interconnect technology. Inspite of its advantages, the biggest hurdle to this technology is that losses of 350dB/cm have been measured in as-deposited polySi waveguide structures, as against ldB/cm losses measured in waveguides fabricated in crystalline silicon. We report methods for reducing scattering and absorption, which are the main sources of losses in this system. To reduce surface scattering losses we fabricate waveguides in smooth recrystallized amorphous silicon and Chemo-Mechanically Polished (CMP) polySi, both of which reduce losses by about 40dB/cm to 15dB/cm. Atomic Force Microscopy (AFM) and spectrophotometry studies are used to monitor surface roughness which has been reduced from an RMS roughness value of 19–20nm down to about 4–6nm. Bulk absorption/scattering losses can depend on size, structure, and quality of grains and grain boundaries which we investigate by means of Transmission Electron Microscopy (TEM). Although the lowest temperature deposition has twice as large a grain size as the highest temperature deposition, the losses appear to not be greatly dependent on grain size in the 0.1pm to 0.4pm range. Additionally, absorption/scattering at dangling bonds is investigated before and after a low temperature Electron-Cyclotron Resonance (ECR) hydrogenation step. After hydrogenation, we obtain the lowest reported polySi loss values at λ = 1.54μm of about 15dB/cm.

Spire Corporation has deposited strontium-barium-niobate by chemical vapor deposition at atmospheric pressure using Ba(TMHD), Sr(TMHD), and Nb ethoxide. Deposition temperature as 550°C in an isothermal furnace. Films were deposited upon silicon (precoated with silica), platinum, sapphire, and quartz. Materials were characterized by RBS, X-ray diffraction, EDS, electron, and optical microscopy. Electrical and optical properties were measured at Boston University.

We report piezoresistance studies in microcrystalline silicon films produced by reactive sputtering from a silicon target in an atmosphere of hydrogen and argon. The microcrystalline silicon films are two phase materials consisting of 50-100Å diameter silicon crystallites embedded in an amorphous Si-Hx matrix. The conductivity of the films was found to decrease significantly when the films were put under compression. Conductivity decreases of up to 100% were observed; this large conductivity changes with strain indicate that microcrystalline silicon is ideally suited for highly sensitive strain gauge applications. The results can be qualitatively accounted for in a model which assumes quantum confinement of carriers in 50Å diameter silicon crystallites separated by tunnelable amorphous Si-Hx barriers.

The construction and characterization of the recombinant clone, pPhoB25 is described. This clone contains an highly repeated sequence of DNA from the fungus Phoma tracheiphila, a pathogen of the lemon. The specificity of the probe was determined by molecular hybridization with the DNA of the host plant and with those of several fungi which can be found associated with the lemon plants. The clone was used successfully as a specific and sensitive probe for the detection of the pathogen in infected plant tissues by dotblot hybridization under laboratory and field conditions.