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Background and purpose The aim was to identify the clinical and diagnostic investigations that may help to support a diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in patients not fulfilling the European Federation of Neurological Societies and Peripheral Nerve Society (EFNS/PNS) electrodiagnostic criteria. Methods The data from patients with a clinical diagnosis of CIDP included in a national database were retrospectively reviewed. Results In all, 535 patients with a diagnosis of CIDP were included. This diagnosis fulfilled the EFNS/PNS criteria in 468 patients (87.2%) (definite in 430, probable in 33, possible in three, while two had chronic immune sensory polyradiculopathy). Sixty-seven patients had a medical history and clinical signs compatible with CIDP but electrodiagnostic studies did not fulfill the EFNS/PNS criteria for CIDP. These patients had similar clinical features and frequency of abnormal supportive criteria for the diagnosis of CIDP compared to patients fulfilling EFNS/PNS criteria. Two or more abnormal supportive criteria were present in 40 (61.2%) patients rising to 54 (80.6%) if a history of a relapsing course as a possible supportive criterion was also included. Increased cerebrospinal fluid proteins and response to immune therapy most frequently helped in supporting the diagnosis of CIDP. Response to therapy was similarly frequent in patients fulfilling or not EFNS/PNS criteria (87.3% vs. 85.9%). Conclusions Patients with a clinical diagnosis of CIDP had similar clinical findings, frequency of abnormal supportive criteria and response to therapy compared to patients fulfilling EFNS/PNS criteria. The presence of abnormal supportive criteria may help in supporting the diagnosis of CIDP in patients with a medical history and clinical signs compatible with this diagnosis but non-diagnostic nerve conduction studies.

ObjectiveTo compare disease course in patients with Guillain-Barré syndrome (GBS) with a poor prognosis who were treated with one or with two intravenous immunoglobulin (IVIg) courses.MethodsFrom the International GBS Outcome Study, we selected patients whose modified Erasmus GBS Outcome Score at week 1 predicted a poor prognosis. We compared those treated with one IVIg course to those treated with two IVIg courses. The primary endpoint, the GBS disability scale at 4 weeks, was assessed with multivariable ordinal regression.ResultsOf 237 eligible patients, 199 patients received a single IVIg course. Twenty patients received an ‘early’ second IVIg course (1–2 weeks after start of the first IVIg course) and 18 patients a ‘late’ second IVIg course (2–4 weeks after start of IVIg). At baseline and 1 week, those receiving two IVIg courses were more disabled than those receiving one course. Compared with the one course group, the adjusted OR for a better GBS disability score at 4 weeks was 0.70 (95%CI 0.16 to 3.04) for the early group and 0.66 (95%CI 0.18 to 2.50) for the late group. The secondary endpoints were not in favour of a second IVIg course.ConclusionsThis observational study did not show better outcomes after a second IVIg course in GBS with poor prognosis. The study was limited by small numbers and baseline imbalances. Lack of improvement was likely an incentive to start a second IVIg course. A prospective randomised trial is needed to evaluate whether a second IVIg course improves outcome in GBS.

BACKGROUND: The International Classification of Functioning, Disability and Health (ICF) Generic-30 Set (previously referred to as Rehabilitation Set) is a minimal set of ICF categories for reporting and assessing functioning and disability in clinical populations with different health conditions along the continuum of care. Recently, the Italian Society of Physical and Rehabilitation Medicine (SIMFER) developed an Italian modification of the simple and intuitive descriptions (SID) of these categories. This study was the first one to implement the use of the SID in practice. AIM: The main aims of this study are: 1) to implement the use of the ICF in clinical practice and research among Italian Residents in PRM, and 2) to verify if the SID made the application of ICF Generic 30 Set more user-friendly than the original descriptions; 3) to examine the prevalence of functioning problems of patients accessing Rehabilitation Services to serve as reference for the development of an ICF-based clinical data collection tool. DESIGN: Multicenter cross-sectional study. SETTING: Italian Physical Medicine and Rehabilitation (PRM) outpatient rehabilitation services. POPULATION: Patients referring to Italian PRM outpatient rehabilitation services and Italian Residents in PRM. METHODS: Each School of Specialization involved, randomly, received the ICF Generic-30 Set with the original descriptions or with the SID. Residents collected over a 4-month period (April-July 2016) patients data related to the ICF Generic-30 Set categories. Moreover, the residents self-assessed their difficulty in using the ICF Generic-30 Set with the original descriptions or with the SID, through a Numeric Rating Scale (NRS). RESULTS: Ninety-three residents collected functioning data of 864 patients (mean aged 57.7±19.3) with ICF Generic-30 Set: 304 with the original descriptions and 560 with SID. The difficulty in using the ICF Generic-30 Set with SID was rated as lower than using the original descriptions (NRS 2.8±2.5 vs. 3.5±3.1; P

The realization of the Hofstadter model in a strongly anisotropic ladder geometry has now become possible in one-dimensional optical lattices with a synthetic dimension. In this work, we show how the Hofstadter Hamiltonian in such ladder configurations hosts a topological phase of matter which is radically different from its two-dimensional counterpart. This topological phase stems directly from the hybrid nature of the ladder geometry, and is protected by a properly defined inversion symmetry. We start our analysis considering the paradigmatic case of a three-leg ladder which supports a topological phase exhibiting the typical features of topological states in one dimension: robust fermionic edge modes, a degenerate entanglement spectrum and a non-zero Zak phase; then, we generalize our findings - addressable in the state-of-the-art cold atom experiments - to ladders with an higher number of legs.

We introduce an algorithm to perform an optimal adiabatic evolution that operates without an apriori knowledge of the system spectrum. By probing the system gap locally, the algorithm maximizes the evolution speed, thus minimizing the total evolution time. We test the algorithm on the Landau-Zener transition and then apply it on the quantum adiabatic computation of 3-SAT: The result is compatible with an exponential speed-up for up to twenty qubits with respect to classical algorithms. We finally study a possible algorithm improvement by combining it with the quantum Zeno effect., Comment: 4 pages, 4 figures

OBJECTIVES: To investigate, using resting state (RS) functional connectivity (FC), the selectivity of involvement of the sensorimotor network in patients with acquired (A) and with hereditary (H) peripheral neuropathies (PN) and the correlations of RS FC abnormalities with clinical impairment and structural brain damage. Temporal associations among RS networks were also explored. Experimental design: RS fMRI scans were acquired from 13 APN, 12 HPN, and 18 age‐ and sex‐matched healthy controls. Independent component analysis and functional network connectivity were used to investigate RS FC within and among RS networks with potential functional relevance. PRINCIPAL OBSERVATIONS: Compared to controls, patients had a decreased FC of the right precentral gyrus and an increased RS FC of the precuneus within the sensorimotor network. Both decreased and increased RS FC also involved the visual and auditory networks, which additionally had an increased coherence of function with the sensorimotor network (more pronounced in HPN). RS FC modifications in patients extended to several cognitive networks and were correlated with disease duration. In APN, they were also correlated with the severity of clinical impairment and corpus callosum atrophy. CONCLUSIONS: In PN, RS FC modifications extend beyond the sensorimotor network and involve other sensory and cognitive networks. The correlations between RS FC patterns and disease duration in patients as well as with clinical impairment in patients with APN suggest that modifications of FC might reflect an adaptive mechanism, which takes time to occur and helps to limit the clinical consequences of peripheral damage. Hum Brain Mapp 35:513–526, 2014. © 2012 Wiley Periodicals, Inc.

In this paper, we prove, extend and review possible mappings between the two-dimensional (2D) cluster state, Wen's model, the 2D Ising chain and Kitaev's toric code model. We introduce a 2D duality transformation to map the 2D lattice cluster state into the topologically ordered Wen model. Then, we investigate how this mapping could be achieved physically, which allows us to discuss the rate at which a topologically ordered system can be achieved. Next, using a lattice fermionization method, Wen's model is mapped into a series of 1D Ising interactions. Considering the boundary terms with this mapping then reveals how the Ising chains interact with one another. The duality of these models can be taken as a starting point to address questions as to how their gate operations in different quantum computational models can be related to each other. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

We introduce a simple method to realize and detect photonic topological Chern insulators with one-dimensional circiut quantum electrodynamics arrays. By periodically modulating the couplings of the array, we show that this one-dimensional model can be mapped into a two-dimensional Chern insulator model. In addition to allowing the study of photonic Chern insulators, this approach also provides a natural platform to realise experimentally Laughlin's pumping argument. Based on scattering theory of topological insulators and input-output formalism, we show that the photonic edge state can be probed directly and the topological invariant can be detected from the winding number of the reflection coefficient phase., Comment: 5 pages, 3 figures

We extend the concept of superadiabatic dynamics, or transitionless quantum driving, to quantum open systems whose evolution is governed by a master equation in the Lindblad form. We provide the general framework needed to determine the control strategy required to achieve superadiabaticity. We apply our formalism to two examples consisting of a two-level system coupled to environments with time-dependent bath operators., Comment: 11 pages, no Figures; accepted for publication in New Journal of Physics

We illustrate a reverse Von Neumann measurement scheme in which a geometric phase induced on a quantum harmonic oscillator is measured using a microscopic qubit as a probe. We show how such a phase, generated by a cyclic evolution in the phase space of the harmonic oscillator, can be kicked back on the qubit, which plays the role of a quantum interferometer. We also extend our study to finite-temperature dissipative Markovian dynamics and discuss potential implementations in micro and nano-mechanical devices coupled to an effective two-level system., Comment: RevTeX4, 4 pages, 2 figures

We study theoretically the electronic entropy and specific heat in diffusive superconductor-normal metal-superconductor (SNS) Josephson junctions. In particular, we consider the influence of non-idealities occurring in an actual experiment, such as the presence of barriers at the NS interfaces, the spin-flip and inelastic scattering in the N region and quasiparticle subgap states in the superconductors. We find that spin-flip and inelastic scattering do not have, for typical parameters values, a large effect. On the contrary, the presence of barriers suppresses the superconducting correlations in the N region, with the consequence that the entropy and the specific heat get reduced eventually to those in the absence of superconductivity for opaque interfaces. Finally we suggest an experiment and check that it is possible, under realistic conditions, to measure the dependence of electronic specific heat on the phase difference between the superconductors., Comment: 8 pages, 10 color figures

Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) received immune globulin intravenous, 10% caprylate/chromatography purified (IGIV-C, Gamunex; n = 59) or placebo (n = 58) every 3 weeks for up to 24 weeks (first period) in a randomized, double-blind, parallel-group, response-conditional, crossover study. Motor and sensory nerves were assessed at baseline and endpoint/week 24. A nonsignificant trend toward improvement in the proximal amplitude of the most severely affected motor nerve was observed with IGIV-C (0.69 +/- 1.86 mV) versus placebo (0.47 +/- 2.29 mV), and a greater improvement of 1.08 +/- 2.15 mV with IGIV-C versus 0.46 +/- 2.03 mV with placebo (P = 0.089) was observed with exclusion of data from Erb's point stimulation. Greater improvements from baseline favoring IGIV-C were observed for 127/142 electrophysiologic parameters. The averaged motor amplitudes from all motor nerves significantly improved with IGIV-C versus placebo [treatment difference, 0.62 mV; 95% confidence interval (CI), 0.05, 1.20; P = 0.035], and conduction block decreased significantly (treatment difference, -5.54%; 95% CI, -10.43, -0.64; P = 0.027), particularly in the lower limbs. Overall, the data suggest that IGIV-C improves electrophysiologic parameters in CIDP.

Many-body states whose wave-function admits a representation in terms of a uniform binary-tree tensor decomposition are shown to obey to power-law two-body correlations functions. Any such state can be associated with the ground state of a translational invariant Hamiltonian which, depending on the dimension of the systems sites, involve at most couplings between third-neighboring sites. A detailed analysis of their spectra shows that they admit an exponentially large ground space., Comment: 6 pages, 2 figures

We propose an architecture for implementing electronic interferometry in quantum Hall bars. It exploits scattering among parallel edge channels. In contrast to previous developments, this one employs a simply connected mesa admitting serial concatenation of building elements closer to optical analogs. Implementations of Mach-Zehnder and Hambury-Brown-Twiss interferometers are discussed together with structures yet unexplored in quantum electronics.

We analyze the broad range of spin-dependent nonequilibrium transport properties of hybrid systems composed of a normal region tunnel coupled to two superconductors with exchange fields induced by the proximity to thin ferromagnetic layers and highlight its functionalities. By calculating the quasiparticle distribution functions in the normal region, we find that they are spin dependent and strongly sensitive to the relative angle between exchange fields in the two superconductors. The impact of inelastic collisions on their properties is addressed. As a result, the electric current flowing through the system is found to be strongly dependent on the relative angle between exchange fields, giving rise to a huge value of magnetoresistance. Moreover, the current presents a complete spin polarization in a wide range of bias voltages, even in the quasiequilibrium case. In the nonequilibrium limit, we parametrize the distributions with an �effective� temperature, which turns out to be strongly spin dependent, though quite sensitive to inelastic collisions. By tunnel coupling the normal region to an additional superconducting electrode, we show that it is possible to implement a spin-polarized current source of both spin species, depending on the bias voltages applied.

The aim of the study was to determine whether intrathecal sufentanil alone provides an adequate analgesia for patients undergoing transurethral resection of the bladder (TURB) and to compare it to standard spinal bupivacaine anesthesia in terms of motor and sensory blockade, discharge time and side effects.Sixty-two patients were blindly and randomly assigned to receive either intrathecal bupivacaine (10 mg of 0.5% hyperbaric bupivacaine) or intrathecal sufentanil (15 microg). Motor and sensory blockade was evaluated using a modified Bromage scale as well as cold and pinprick tests. Severity of pain was assessed by means of a 10-point verbal analog scale.We found that the mean duration of sensory blockade was similar for both sufentanil and bupivacaine patients but the quality of analgesia induced by sufentanil alone was poor as compared with spinal bupivacaine anesthesia.The subarachnoid administration of sufentanil 15 mg seems to be inadequate for TURB surgery. In addition, the advantage of a faster recovery we observed in sufentanil patients is minimized by the occurrence of a troublesome symptom such as pruritus. On the other hand, spinal bupivacaine produces an undesirable motor blockade exceeding, in our opinion, the requirement for TURB procedure.

A high degree of quantum coherence is a crucial requirement for the implementation of quantum logic devices. Solid state nanodevices seem particularly promising from the point of view of integrability and flexibility in the design. However decoherence is a serious limitation, due to the presence of many types low energy excitations in the ``internal'' environment and of ``external'' sources due to the control circuitery. Here we study both kind of dephasing in a special implementation, the charge Josephson qubit, however many of our results are applicable to a large class of solid state qubits. This is the case of 1/f noise for which we introduce and study a model of an environment of bistable fluctuatiors. External sources of noise are analized in terms of a suitable harmonic oscillator environment and the explicit mapping on the spin boson model is presented. We perform a detailed investigation of various computation procedures (single shot measurements, repeated measurements) and discuss the problem of the information needed to characterize the effect of the environment. For a fluctuator environment with 1/f spectrum memory effects turn out to be important. Although in general information beyond the power spectrum is needed, in many situations this results in the knowledge of only one more microscopic parameter of the environment. This allows to determine which degrees of freedom of the environment are effective sources of decoherence in each different physical situation considered., Comment: 25 pages, 15 figures, Proc. of the International School of Physics "Enrico Fermi", Course CLI, Varenna (Italy) July 2002. To be published in "Quantum Phenomena of Mesoscopic Systems", B. Altshuler and V. Tognetti Eds, IOS Press Amsterdam

Objective To assess the efficacy of recombinant human erythropoietin (rhEPO) in amyotrophic lateral sclerosis (ALS). Methods Patients with probable laboratory-supported, probable or definite ALS were enrolled by 25 Italian centres and randomly assigned (1:1) to receive intravenous rhEPO 40 000 IU or placebo fortnightly as add-on treatment to riluzole 100 mg daily for 12 months. The primary composite outcome was survival, tracheotomy or >23 h non-invasive ventilation (NIV). Secondary outcomes were ALSFRS-R, slow vital capacity (sVC) and quality of life (ALSAQ-40) decline. Tolerability was evaluated analysing adverse events (AEs) causing withdrawal. The randomisation sequence was computer-generated by blocks, stratified by centre, disease severity (ALSFRS-R cut-off score of 33) and onset (spinal or bulbar). The main outcome analysis was performed in all randomised patients and by intentionto-treat for the entire population and patients stratified by severity and onset. The study is registered, EudraCT 2009-016066-91. Results We randomly assigned 208 patients, of whom 5 (1 rhEPO and 4 placebo) withdrew consent and 3 ( placebo) became ineligible (retinal thrombosis, respiratory insufficiency, SOD1 mutation) before receiving treatment; 103 receiving rhEPO and 97 placebo were eligible for analysis. At 12 months, the annualised rate of death (rhEPO 0.11, 95% CI 0.06 to 0.20; placebo: 0.08, CI 0.04 to 0.17), tracheotomy or >23 h NIV (rhEPO 0.16, CI 0.10 to 0.27; placebo 0.18, CI 0.11 to 0.30) did not differ between groups, also after stratification by onset and ALSFRS-R at baseline. Withdrawal due to AE was 16.5% in rhEPO and 8.3% in placebo. No differences were found for secondary outcomes. Conclusions RhEPO 40 000 IU fortnightly did not change the course of ALS.

As an alternative to conventional batteries and other energy scavenging techniques, this paper introduces the idea of using micro-turbines to extract energy from wind forces at the microscale level and to supply power to battery-less microsystems. Fundamental research efforts on the design, fabrication, and test of micro-turbines with blade lengths of just 160 μm are presented in this paper along with analytical models and preliminary experimental results. The proof-of-concept prototypes presented herein were fabricated using a standard polysilicon surface micro-machining silicon technology (PolyMUMPs) and could effectively transform the kinetic energy of the available wind into a torque that might drive an electric generator or directly power supply a micro-mechanical system. Since conventional batteries do not scale-down well to the microscale, wind micro-turbines have the potential for becoming a practical alternative power source for microsystems, as well as for extending the operating range of devices running on batteries.

The transition line of superconducting arrays of holes exhibits a rich field structure due to the interference of superconducting states nucleated at the holes edges. We studied by means of resistance measurements their effect on the T*c(H) line as a function of transverse magnetic field using regular arrays of nanofabricated micron size holes. The arrays transition fields are higher than for the bulk. Moreover we found a nontrivial field modulation of the T*c(H) line with an inversion, with increasing field, of the modulation concavity which we assigned to a crossover from a collective to an isolated edge state regime. The high field regime is well described by the nucleation at a single hole in an infinite film. The modulation at low fields was found to be dominated by the interference of neighbor edge states when the inter-hole distance w becomes comparable to the temperature dependent coherence length. A comparison between arrays of different hole shape shows the influence of geometry on the type of interaction established, which can described either as a superconducting wire network or as a weak link array., Comment: revised version, fig.4 changed 23 pages, 7 figures, submitted to Journal of Low Temperature Physics