294 research outputs found

    effect of intrathecal baclofen botulinum toxin type a and a rehabilitation programme on locomotor function after spinal cord injury a case report

    Get PDF
    Objective: a few studies have reported the use of botulinum toxin injections after spinal cord injury, as this is the gold standard to treat focal spasticity. We report such a case here. Case report: a 38-year-old woman who had become paraplegic and care-dependent secondary to cervico-thoracic intramedullary ependymoma, presented 8 months later with painful lower limb spasticity, which was being treated with oral anti-spastic and benzodiazepine drugs with no therapeutic effect. We treated the patient with intrathecal baclofen to reduce her spasticity and in order to avoid the major side-effects of high dosages of oral baclofen. after motor rehabilitation programmes, which included functional ele

    Scientific data compression for the Solar Wind Analyser onboard Solar Orbiter

    Get PDF

    One year of tropospheri clidar measurements of aerosol extinction and backscatter

    Get PDF
    The aerosol lidar system operational at IMAA-CNR in Tito Scalo (PZ) (Southern Italy, 40°36'N, 15°44'E, 820 m above sea level) is part of the EARLINET project. Systematic lidar measurements of aerosol backscatter and extinction in the troposphere have been performed since May 2000. Aerosol backscatter measurements were performed at both 355 nm and 532 nm, while aerosol extinction coeffi cient were retrieved from simultaneous N2 Raman backscatter signals at 386.6 nm. The observations were performed on a regular schedule of two night time measurements per week (around sunset) and one daytime measurement per week (around 13:00 UTC). Furthermore, special observations concerning Saharan dust outbreaks have been carried out. Starting in May 2000 the lidar measurements performed in Tito Scalo have been collected and analysed. Preliminary results regarding the fi rst year of measurements are reported. In particular, the evolution of the aerosol integrated backscatter and extinction as well as of the mean value of the lidar ratio in the whole aerosol layer is reported. Results show clear evidence of seasonal variation of the observed parameters, with higher values and greater variability during summertime

    Growth methods of c-axis oriented MgB2 thin films by pulsed laser deposition

    Full text link
    High quality MgB2 thin films have been obtained by pulsed laser deposition both on MgO and on Al2O3 substrates using different methods. In the standard two-step procedure, an amorphous precursor layer is deposited at room temperature starting both from stoichiometric target and from boron target: after this first step, it is annealed in magnesium atmosphere in order to crystallize the superconducting phase. The so obtained films show a strong c-axis orientation, evidenced by XRD analysis, a critical temperature up to 38 K and very high critical fields along the basal planes, up to 22T at 15K. Also an in situ one step technique for the realization of superconducting MgB2 thin films has been developed. In this case, the presence of an argon buffer gas during deposition is crucial and we observe a strong dependence of the quality of the deposited film on the background gas pressure. The influence of the Ar atmosphere has been confirmed by time and space-resolved spectroscopy measurements on the emission spectrum of the plume. The Ar pressure modifies strongly the plasma kinetics by promoting excitation and ionization of the plume species, especially of the most volatile Mg atoms, increasing their internal energy.Comment: Paper presented at Boromag Workshop, Genoa 17-19 June 2002, in press on SUS

    Is the Shroud of Turin in Relation to the Old Jerusalem Historical Earthquake?

    Full text link
    Phillips and Hedges suggested, in the scientific magazine Nature (1989), that neutron radiation could be liable of a wrong radiocarbon dating, while proton radiation could be responsible of the Shroud body image formation. On the other hand, no plausible physical reason has been proposed so far to explain the radiation source origin, and its effects on the linen fibres. However, some recent studies, carried out by the first author and his Team at the Laboratory of Fracture Mechanics of the Politecnico di Torino, found that it is possible to generate neutron emissions from very brittle rock specimens in compression through piezonuclear fission reactions. Analogously, neutron flux increments, in correspondence to seismic activity, should be a result of the same reactions. A group of Russian scientists measured a neutron flux exceeding the background level by three orders of magnitude in correspondence to rather appreciable earthquakes (4th degree in Richter Scale). The authors consider the possibility that neutron emissions by earthquakes could have induced the image formation on Shroud linen fibres, trough thermal neutron capture by Nitrogen nuclei, and provided a wrong radiocarbon dating due to an increment in C(14,6)content. Let us consider that, although the calculated integral flux of 10^13 neutrons per square centimetre is 10 times greater than the cancer therapy dose, nevertheless it is100 times smaller than the lethal dose.Comment: 13 pages, 1 figur

    Solar wind analyzer - The solar orbiter milestone towards on-board intelligent decision making systems

    Get PDF
    The most important challenge underpinning the transition to next generation of space missions design is the discrepancy between the dramatic increases in observation rate and the marginal increase in downlink capacity, enforcing the shift from the traditional “acquire-compress-transmit” paradigm to highly efficient intelligent on-board processing of observations, minimizing downlink requirements while respecting the limitations in power and bandwidth resources. Solar Orbiter (SO), an ESA/NASA mission, is a milestone both in the purely technological and scientific sphere. SO is designed to study the connection between the Sun and the heliosphere, with particular interest to open issues such as the sources of solar wind streams and turbulence, the heliospheric variability, the origin of energetic particles and the solar dynamo. The selected science payload is required to support making the link between in-situ and remote sensing observations, and is composed of ten instruments or suites of instruments including spectrometers, imagers, wave and particle instruments – many the result of large international consortia. In particular, the plasma suite Solar Wind Analyzer (SWA) comprises: Proton-Alpha Sensor (PAS), Electron Analyzer System (EAS), Heavy Ion Sensor (HIS) together with the Data Processing Unit (DPU), and will provide high-resolution 3D velocity distribution function of ions and electrons, together with ion composition, necessary to infer the thermal state of solar wind and its source regions, identify structures such as shocks, CME's and other transients, and determine the link between particle dynamics and waves. SO will explore new distance and latitude regions that remain unexplored, even accounting for existing Helios and upcoming Parker Solar Probe observations. The technical challenges include heavy constraints such as the limited bandwidth available to SWA for downlink, so that the whole set of raw particle data collected cannot be transmitted back to ground. Data processing is thus used to evaluate concise scientific properties of the solar wind, particularly the moments of the particle velocity distribution functions (VDF), such that it is then acceptable to transmit the full VDF data only at low frequencies. Then processing is re-adopted on these distributions to meet the required (lossless) compression rates (2-8). Another step towards the aforementioned paradigm shift is represented by the SWA Book-Keeping Algorithm (BKA), which has been designed to ensure that the individual sensors remain within the allocated telemetry rate on an orbit-averaged basis. The philosophy of the SWA book-keeping scheme has since been applied to all instruments with ESOC’s Operations Team introducing the concept of Operations Telemetry Corridors (OTC) to finely tune the rate of telemetry generation by the instruments

    The psychological impact of COVID-19 pandemic on patients with neuroendocrine tumors: Between resilience and vulnerability

    Get PDF
    The COVID-19 pandemic has added another layer of complexity to the fears of patients with neuroendocrine tumors (NETs). Little is known regarding the psychological impact of the COVID-19 outbreak on patients with gastroenteropancreatic or bronchopulmonary (BP) NETs. We longitudinally surveyed the mental symptoms and concerns of NET patients during the plateau phase of the first (W1) and second epidemic waves (W2) in Italy. Seven specific constructs (depression, anxiety, stress, health-related quality of life, NET-related quality of life, patient–physician relationship, psychological distress) were investigated using validated screening instruments, including DASS-21, EORTC QLQ-C30, EORTC QLQ GI.NET21, PDRQ9 and IES-R. We enrolled 197 patients (98 males) with a median age of 62 years. The majority of the patients had G1/G2 neoplasms. Some 38% of the patients were on active treatment. At W1, the prevalence of depression, anxiety and stress was 32%, 36% and 26% respectively. The frequency of depression and anxiety increased to 38% and 41% at W2, whereas no modifications were recorded in the frequency of stress. Poor educational status was associated with higher levels of anxiety at both W1 (odds ratio [OR] = 1.33 Â± 0.22; p =.07) and W2 (OR = 1.45 Â± 0.26; p =.03). Notably, post-traumatic stress symptoms were observed in the 58% of the patients, and both single marital status (OR = 0.16, 95% confidence interval [CI] = 0.06–0.48; p =.0009) and low levels of formal education (OR = 0.47, 95% CI = 0.23–0.99; p =.05) predicted their occurrence. No significant deteriorations of health-related quality of life domains were observed from W1 to W2. High patient care satisfaction was documented despite the changes in health systems resource allocation. NET patients have an increased risk of developing post-traumatic stress symptoms as result of the COVID-19 pandemic. Specific screening measures and psychological interventions should be implemented in NET clinics to prevent, recognize and treat mental distress in this vulnerable population

    Pauli Blocking of Collisions in a Quantum Degenerate Atomic Fermi Gas

    Full text link
    We have produced an interacting quantum degenerate Fermi gas of atoms composed of two spin-states of magnetically trapped 40^{40}K. The relative Fermi energies are adjusted by controlling the population in each spin-state. Measurements of the thermodynamics reveal the resulting imbalance in the mean energy per particle between the two species, which is as large as a factor of 1.4 at our lowest temperature. This imbalance of energy comes from a suppression of collisions between atoms in the gas due to the Pauli exclusion principle. Through measurements of the thermal relaxation rate we have directly observed this Pauli blocking as a factor of two reduction in the effective collision cross-section in the quantum degenerate regime.Comment: 11 pages, 4 figure

    Theory of output coupling for trapped fermionic atoms

    Full text link
    We develop a dynamic theory of output coupling, for fermionic atoms initially confined in a magnetic trap. We consider an exactly soluble one-dimensional model, with a spatially localized delta-type coupling between the atoms in the trap and a continuum of free-particle external modes. Two important special cases are considered for the confinement potential: the infinite box and the harmonic oscillator. We establish that in both cases a bound state of the coupled system appears for any value of the coupling constant, implying that the trap population does not vanish in the infinite-time limit. For weak coupling, the energy spectrum of the outgoing beam exhibits peaks corresponding to the initially occupied energy levels in the trap; the height of these peaks increases with the energy. As the coupling gets stronger, the energy spectrum is displaced towards dressed energies of the fermions in the trap. The corresponding dressed states result from the coupling between the unperturbed fermionic states in the trap, mediated by the coupling between these states and the continuum. In the strong-coupling limit, there is a reinforcement of the lowest-energy dressed mode, which contributes to the energy spectrum of the outgoing beam more strongly than the other modes. This effect is especially pronounced for the one-dimensional box, which indicates that the efficiency of the mode-reinforcement mechanism depends on the steepness of the confinement potential. In this case, a quasi-monochromatic anti-bunched atomic beam is obtained. Results for a bosonic sample are also shown for comparison.Comment: 16 pages, 7 figures, added discussion on time-dependent spectral distribution and corresponding figur

    Towards quantum 3d imaging devices

    Get PDF
    We review the advancement of the research toward the design and implementation of quantum plenoptic cameras, radically novel 3D imaging devices that exploit both momentum–position entanglement and photon–number correlations to provide the typical refocusing and ultra-fast, scanning-free, 3D imaging capability of plenoptic devices, along with dramatically enhanced performances, unattainable in standard plenoptic cameras: diffraction-limited resolution, large depth of focus, and ultra-low noise. To further increase the volumetric resolution beyond the Rayleigh diffraction limit, and achieve the quantum limit, we are also developing dedicated protocols based on quantum Fisher information. However, for the quantum advantages of the proposed devices to be effective and appealing to end-users, two main challenges need to be tackled. First, due to the large number of frames required for correlation measurements to provide an acceptable signal-to-noise ratio, quantum plenoptic imaging (QPI) would require, if implemented with commercially available high-resolution cameras, acquisition times ranging from tens of seconds to a few minutes. Second, the elaboration of this large amount of data, in order to retrieve 3D images or refocusing 2D images, requires high-performance and time-consuming computation. To address these challenges, we are developing high-resolution single-photon avalanche photodiode (SPAD) arrays and high-performance low-level programming of ultra-fast electronics, combined with compressive sensing and quantum tomography algorithms, with the aim to reduce both the acquisition and the elaboration time by two orders of magnitude. Routes toward exploitation of the QPI devices will also be discussed
    • …
    corecore