Plasticity and dystonia: a hypothesis shrouded in variability.

Studying plasticity mechanisms with Professor John Rothwell was a shared highlight of our careers. In this article, we discuss non-invasive brain stimulation techniques which aim to induce and quantify plasticity, the mechanisms and nature of their inherent variability and use such observations to review the idea that excessive and abnormal plasticity is a pathophysiological substrate of dystonia. We have tried to define the tone of our review by a couple of Professor John Rothwell's many inspiring characteristics; his endless curiosity to refine knowledge and disease models by scientific exploration and his wise yet humble readiness to revise scientific doctrines when the evidence is supportive. We conclude that high variability of response to non-invasive brain stimulation plasticity protocols significantly clouds the interpretation of historical findings in dystonia research. There is an opportunity to wipe the slate clean of assumptions and armed with an informative literature in health, re-evaluate whether excessive plasticity has a causal role in the pathophysiology of dystonia

Surfactant Aided Reductive Carbonylation of Nitrobenzene inWater Catalyzed by Pd Complexes

The catalytic carbonylation of nitroarenes is a field of high interest from a technological point of view, since provides an environmentally benign route to a number of important industrial products, such as isocyanates, carbamates, ureas, azoarenes and azoxyarenes, amines, amides, oximes and several types of heterocyclic compounds. The reductive carbonylation of nitrobenzene in water carried out by using Pd(II)-solvable catalyst precursors, leads to aniline, as major product. In the present paper we propose the micellar catalytic reductive carbonylation of nitrobenzene in water. The Pd(II) catalyst precursors tested are synthesized by using cheaper commercial insolvable ligands, such as triphenylphosphine (PPh3), 1,3- bis(diphenylphosphino)propane (dppp) and 1, 10-phenantroline (phen). The influence on the conversion and on the selectivity of such precursors has been evaluated in combination with commercial anionic (SDS), cationic (TBAB) and non ionic (Triton X 100) surfactants. We have found that all the Pd(II) complexes tested are efficiently dissolved in each O/W emulsions but the conversion is strongly influenced by the nature of ligand. By using Pd(OAc)2(PPh3)2, high selectivity towards azo- and azo-oxybenzene has been obtained. The influence of some reaction parameters has been further evaluated and optimized

Arte e architettura liberty in Sicilia

Gli ultimi decenni del 1800 e i primi del 1900 sono un periodo storico nel quale la Sicilia ha trovato forme espressive di alto valore capaci di confrontarsi con il resto d\u2019Europa; forse il periodo pi\uf9 produttivo della Sicilia moderna e insieme della sua capacit\ue0 di sviluppare cultura in modo autonomo, di allacciare relazioni con l\u2019esterno e di esportare anche saperi, maestranze e alte professionalit\ue0. Il periodo esprime una grande vivacit\ue0 imprenditoriale e politica e il Liberty \ue8 quell\u2019espressione nuova, mirabile sintonia di capacit\ue0 di lavoro ed elaborazione culturale, che non sarebbe attecchita in Sicilia e in Italia se non avesse incontrato una classe dirigente che l\u2019ha voluta e sostenuta, sino a farla diventare un linguaggio delle arti capillarmente diffuso e universalmente sentito. Riprendere questo fenomeno con un testo completo che oltre le citt\ue0 capitali, guarda l\u2019intero territorio regionale, ha significato proporre una formula editoriale costituita da un contenitore che raccoglie pi\uf9 prodotti. I quattordici itinerari in cui \ue8 articolato il territorio regionale sono presentati in quattordici piccoli libri, per rendere pi\uf9 snella la consultazione e perch\ue9 possano essere utile compagnia e guida a quanti vorranno affrontare la visita ai luoghi del Liberty in Sicilia. Il volume pi\uf9 corposo, con il contributo di scritti di autorevoli studiosi, definisce ulteriori interpretazioni sia attraverso \uabsaggi\ubb di carattere generale che \uabapprofondimenti\ubb su alcune questioni per fornire ragioni alla riflessione critica sulla Sicilia come regione leader dell\u2019Art Nouveau nel contesto nazionale. (da IV^ di copertina

Cognitive processess and cognitive reserve in multiple sclerosis

Multiple Sclerosis (MS) is characterized by motor, cognitive, and neuropsychiatric symptoms, which can occur independently. While MS is traditionally considered an inflammatory disease of the white matter, degeneration of gray matter is increasingly recognized as an important contributor to the progressive cognitive decline. A protective factor against the progression of cognitive dysfunction in MS could be the cognitive reserve, defined as resistance to brain dysfunction. Aim of the present study is to evaluate the role of cognitive reserve for different aspects of cognitive dysfunction of patients with MS. We found that patients with MS and lower cognitive reserve have poorer neuropsychological performance and slower information speed processing. These findings support the notion that intellectual reserve may protect some aspects of cognitive function in patients with MS

Pd(II)-catalyzed emulsion copolymerization of carbon monoxide with ethene in CH2Cl2/water as a solvent

Chemical, physical and mechanical characteristics of alt poly(1-oxo-trimethylene) [1] well fit with a wide range of industrial applications and recently several researchers have shown a renovated keen interest for the application of such a polymer in the field of fibers [2]. In order to obtain fibers, however, high molecular weight polymers are required. In some papers we have reported that high molecular weight polymers require high pressure and low temperature but the nature of the solvent must be considered too [2-4]. The choose of the solvent influences both the activity of the catalyst and the average molecular weight of the polymer. Usually the catalysis is efficiently carried out in methanol by using the [Pd(OAc)2(DPPP)] complex in the presence of an acid (p-toluenesulfonic, TsOH) [5] which leads to polymers with not so high average molecular weight. By replacing methanol with CH3COOH-water also [PdCl2(DPPP)] complex efficiently catalyzes the reaction leading also to an increase of the polymer molecular weight [3]. By continuing the research on the influence of the solvent on the molecular weight, here we report our preliminary results on the preparation of alt- poly(1-oxo-trimethylene) by emulsion catalytic polymerization. The [PdCl2(DPPP)] complex has been dissolved in a CH2Cl2-H2O emulsion and the productivity has been optimized

The catalytic copolymerization of ethene with carbon monoxide efficiently carried out in water/dichloromethane/sodium dodecylsulfate emulsion

The CO-ethene copolymerization has been efficiently carried out in the water/CH2Cl2 emulsion by using water insolvable Pd(II) complexes. By using the surfactant SDS very high molecular weight copolymers have been obtained with high productivity (ca. 13,000 g/(gPd.h))

Abnormal plasticity of sensorimotor circuits extends beyond the affected body part in focal dystonia

Objective: To test whether abnormal sensorimotor plasticity in focal hand dystonia is a primary abnormality or is merely a consequence of the dystonic posture. Methods: This study used the paired associative stimulation (PAS) paradigm, an experimental intervention, capable of producing long term potentiation (LTP) like changes in the sensorimotor system in humans. PAS involves transcranial magnetic stimulation combined with median nerve stimulation. 10 patients with cranial and cervical dystonia, who showed no dystonic symptoms in the hand, and nine patients with hemifacial spasm (HFS), a non-dystonic condition, were compared with 10 healthy age matched controls. Motor evoked potential amplitudes and cortical silent period (CSP) duration were measured at baseline before PAS and for up to 60 min (T0, T30 and T60) after PAS in the abductor pollicis brevis and the first dorsal interosseus muscles. Results: Patients with dystonia showed a stronger increase in corticospinal excitability than healthy controls and patients with HFS. In addition, patients with dystonia showed a loss of topographical specificity of PAS induced effects, with a facilitation in both the median and ulnar innervated muscles. While PAS conditioning led to a prolonged CSP in healthy controls and patients with HFS, it had no effect on the duration of the CSP in patients with cranial and cervical dystonia. Conclusion: The data suggests that excessive motor cortex plasticity is not restricted to the circuits clinically affected by dystonia but generalises across the entire sensorimotor system, possibly representing an endophenotypic trait of the disease

Designing a double-coated cathode with high entropy oxides by microwave-assisted hydrothermal synthesis for highly stable Li–S batteries

Nowadays, Li-S batteries are considered as one of the most promising alternatives to Li-ion technology in the near future, thanks to their high specific capacity and their significantly lower environmental impact and production costs. Consequently, many efforts have been directed to tackle with the inherent issues that affect Li-S batteries. One of the main problems is the so-called shuttle effect, which basically entails the unwanted migration of lithium polysulfides (LiPSs) from the cathode to the anode side, causing the degradation of the cell. Here, we report an effective strategy to restrain the shuttle effect and increase the kinetics at the cathode of the lithium-sulfur (Li-S) battery. A functional layer including high entropy oxides (HEO) coated onto the sulfur cathode allows to exploit the HEOs capability as promoter catalysts for the conversion of LiPSs. Pure HEO powders are synthesized by fast, highly efficient microwave irradiation, followed by heat treatment at 930 degrees C. The formation of highly crystalline HEO is confirmed by X-ray diffraction analysis. The LiPSs adsorption capability of HEO is evaluated by UV-vis and X-ray photoelectron spectroscopy analyses. The effect of the HEO-coated sulfur cathode on the electrochemical performance of the Li-S battery is studied by cyclic voltammetry and galvanostatic charge/discharge. The cell with double-coated cathode delivers an initial discharge capacity of 1173 mAh/g at C/10 with 45% capacity retention over 500 cycles at C/5, approaching similar to 99% coulombic efficiency.[GRAPHICS]

Hydrogenation of nitrobenzene to 4-aminophenol in a fully reusable solvent system, by using Pt, Rh, Pd supported on carbon-CF3COOH catalytic system

4-Aminophenol is an important raw material for several products in the field of dyes, photographs and pharmaceutics. For instance, paracetamol (N-acetyl-4-aminophenol) a widely employed analgesic and antipyretic whose production is in continuous growth specially in the far east region. Industrial synthesis of paracetamol is based mainly on 4-aminophenol, which is obtained by three different routes: i) nucleophilic substitution of the Cl of the 4-chloronitrobenzene, ii) reduction of 4-nitro-phenol, iii) selective hydrogenation of nitrobenzene [1]. The selective hydrogenation of nitrobenzene is however, the most convenient from both economical and environmental point of view [1, 2]. The major concern of this process is, however, the presence of H2SO4, which is origin of corrosion, safety, environmental and separation problems. The reaction is typically carried out in CSTR in which the biphasic reaction medium is used to accomplish simultaneously the Pt catalyzed hydrogenation of nitrobenzene and the acid catalyzed Bamberger rearrangement of the intermediate N-phenylhydroxylamine. From environmental point of view, the major drawback of the process is the neutralization of the acidic phase, with the consequent by-production of sulfate salts, which are undesired wastes. Starting from recent results obtained in the Beckmann rearrangement of the cyclohexanone oxime in CH3CN-CF3COOH system [3], here we show some findings on the hydrogenation of nitrobenzene to 4-aminophenol in a single liquid phase CH3CN-H2O-CF3COOH and in the presence a hydrogenation catalyst. The easy of recovery of solvent and catalysts allows to develop a greener process than that based on the biphasic H2SO4-nitrobenzene syste

Environmentally friendly corrosion inhibitor of the copper in 0.5 M sulphuric acid solution.

Environmentally friendly corrosion inhibitor of the copper in 0.5 M sulphuric acid solution. G. Quartarone,a L. Ronchin,a A. Vavasori,a C. Tortato,a L. Bonaldo.b aUniversity of Venice, Dep. of Chemistry, Dorsoduro. 2137, 30123 Venice. E-mail: [email protected] bLubrikn, production of additives for lubricant, via Dell’Artigianato, 38, 30030 Vicenza. Copper corrosion inhibition by gramine [3-(dimethylaminomethyl)indole] in the 0.5 M sulphuric acid solutions was studied in the temperature range 25-55 °C using electrochemical impedance spectroscopy techniques (EIS). Gramine was dissolved at various concentrations (from 5∙10-4 to 7.5∙10-3) in 0.5 M sulphuric acid. The surface preparation of the specimens was carried out using silicon carbide paper up to grade 1200. EIS measurements were performed after dipping the working electrode into the 0.5 M sulphuric acid solutions with or without inhibitor at Ecorr with an a.c. voltage amplitude of 5mV. The frequency range was swept between 100 kHz and 10 mHz with 10 point for hertz decade. The presence of gramine led to changes of the impedance plots in both shape and size. The plots of Nyquist exhibited that some impedance spectra consisted of one capacitive loop at the higher frequencies which was attributed to a faradaic process involving a charge transfer resistance in parallel with double-layer capacitance element [1]. The size of the capacitive arc increased by increasing the concentration of gramine. This indicated that gramine increased the charge transfer resistance and then it had an inhibiting effect on copper corrosion in 0.5 M sulphuric acid solutions. Inhibition efficiencies results showed that the gramine inhibited the copper corrosion in the temperature range 25-55 °C reaching the maximum value of 86% at 55 °C. Impedance spectra also showed a depression of Nyquist-plot semicircles that can be related to the surface heterogeneity due the microscopic roughness of the electrode surface and inhibitor adsorption [2]. Moreover at the lower frequencies in both the uninhibited solutions and inhibited ones by lower inhibitor concentrations, the Warburg impedance appeared. In the copper corrosion in oxygenated sulphuric acid solutions at Ecorr the anodic reaction is copper dissolution and cathodic reaction is oxygen reduction being the hydrogen discharge current density negligible as compared to oxygen reduction current density. Then the Warburg impedance could be attributed to oxygen transport from the bulk solution to the copper surface [3]. The adsorption behaviour of gramine followed Temkin’s isotherm. The values of the standard free energy of adsorption of the gramine at 25 °C, 35 °C, 45 °C and 55°C were calculed. A structural model of the interface copper/0.5 M H2SO4 was proposed. [1] O.E. Barcia and O.R. Mattos, Electrochim. Acta 35, 1990, 1601. [2] H. Ashassi-Sorkhabi, N. Ghalebsaz-Jeddi, F. Hasemzadeh and H. Jahani, Electrochim. Acta 51, 2006, 3848. [3] H. Ma, S. Chen, B. Yin, S. Zhao, X. Liu, Corros. Sci., 45, 2003, 867