Transition of amorphous to crystalline oxide film in initial oxide overgrowth on liquid metals

It is important to understand the mechanism of oxidation in the initial stage on the free surface of liquid metals. Mittemeijer and co-workers recently developed a thermodynamic model to study the oxide overgrowth on a solid metal surface. Based on this model, we have developed a thermodynamic model to analyse the thermodynamic stability of oxide overgrowth on liquid metals. The thermodynamic model calculation revealed that the amorphous oxide phase is thermodynamically preferred up to 1.3 and 0.35 nm respectively, in the initial oxide overgrowth on liquid Al and Ga at the corresponding melting point. However, the amorphous phase is thermodynamically unstable in the initial oxide overgrowth on liquid Mg. The thermodynamic stability of amorphous phase in the Al and Ga oxide systems is attributed to lower sums of surface and interfacial energies for amorphous phases, compared to that of the corresponding crystalline phases.Financial support under grant EP/H026177/1 from the EPSRC was used

Anti-myelin-associated glycoprotein polyneuropathy coexistent with CREST syndrome

Clinical involvement of the peripheral nervous system in the calcinosis cutis, raynaud′s phenomenon, esophageal dismotility, sclerodactyly and telangiectasia (CREST) variant of systemic sclerosis occurs infrequently and is characterized by axonal degeneration due to necrotizing vasculitis. We report a female patient with a known history of CREST syndrome, which developed a slowly progressive, distal symmetric demyelinating sensorimotor polyneuropathy (PN), with tremor and ataxia as prominent features, compatible with anti-myelin associated glycoprotein (MAG) PN. The diagnosis of PN was established by the presence of monoclonal immunoglobulin M anti-MAG antibodies (Thin-Layer Chromatography, Western Blot and enzyme-linked immunoabsorbent assay). Given the evidence that in CREST activation of T-helper cells is observed and that anti-MAG antibodies, despite the fact that they are T-cell-independent, may be influenced by an increase in T-helper function, the coexistence of these two rare autoimmune disorders in the same patient may not be incidental but related to the underlying immunological mechanisms involved

Anti-myelin-associated glycoprotein polyneuropathy coexistent with CREST syndrome

Clinical involvement of the peripheral nervous system in the calcinosis cutis, raynaud′s phenomenon, esophageal dismotility, sclerodactyly and telangiectasia (CREST) variant of systemic sclerosis occurs infrequently and is characterized by axonal degeneration due to necrotizing vasculitis. We report a female patient with a known history of CREST syndrome, which developed a slowly progressive, distal symmetric demyelinating sensorimotor polyneuropathy (PN), with tremor and ataxia as prominent features, compatible with anti-myelin associated glycoprotein (MAG) PN. The diagnosis of PN was established by the presence of monoclonal immunoglobulin M anti-MAG antibodies (Thin-Layer Chromatography, Western Blot and enzyme-linked immunoabsorbent assay). Given the evidence that in CREST activation of T-helper cells is observed and that anti-MAG antibodies, despite the fact that they are T-cell-independent, may be influenced by an increase in T-helper function, the coexistence of these two rare autoimmune disorders in the same patient may not be incidental but related to the underlying immunological mechanisms involved

Asymptomatic elevation of serum creatine kinase leading to the diagnosis of 4q35 facioscapulohumeral muscular dystrophy

Persistent, asymptomatic (hyperCKemia) may be the prelude to, or the sole manifestation of, a neuromuscular disease. However, the clinical spectrum of facioscapulohumeral muscular dystrophy (FSHD) ranges from asymptomatic individuals with minimal clinical signs to patients who are wheelchair-bound. We describe a patient with persistent, asymptomatic hyperCKemia who received the diagnosis of 4q35 FSHD after a thorough stepwise investigation. © 2009 Elsevier Ltd. All rights reserved

Patients with ocular symptoms referred for electrodiagnosis: how many of them suffer from myasthenia gravis?

The aim of this study was the diagnosis of patients with isolated ocular manifestations (ptosis and/or diplopia) referred for electrophysiological evaluation to the electrodiagnostic laboratory of a University Neurological Department. Examination was performed either in inpatient status or in outpatient basis. We analyzed the clinical, electrophysiological and other laboratory data in 79 subjects. Myasthenia gravis (MG) was diagnosed in 38 %, 45.6 % in other diseases (Graves disease, blepharospasm, IIId cranial verve palsy, multiple sclerosis, stroke, etc.), while in 16.5 %, the cause remained unidentified. Symptoms fluctuation was significantly more frequent in the myasthenic patients, compared to patients with other diseases. The presence of both diplopia and ptosis are more likely due to MG rather than other pathology. © 2015, Belgian Neurological Society

Interfacial Properties and Structure Stability of Ni/Y2O3-ZrO2-TiO2 Cermet Anodes for Solid Oxide Fuel Cells

Ceramics of the ternary system Y2O3-ZrO2-TiO2 (YZT) and Ni/YZT cermets are evaluated in terms of application as anode electrodes in a Solid Oxide Fuel Cell. Wetting experiments in liquid Ni/YZT systems show that the increase of TiO2 content in the ceramic phase improves the bond strength at the metal ceramic interface, due to the reduction of the interfacial energy. Ni(40 vol%)/YZT cermets are exposed at 1000 degrees C for up to 1000 h in reducing atmosphere and exhibit an improved long term stability regarding to the electrical conductivity and the microstructure compared to the "state of the art" Ni/8YSZ (yttria(8 mol%)-stabilized zirconia) cermet. This is explained by the enhanced adherence at the Ni/ceramic interface, which suppresses the agglomeration rate of the Ni particles. The improvement of the interfacial properties diminishes the TEC values of the Ni/YZT cermets constraining the thermal expansion mismatch between the cermet anode and the 8YSZ electrolyte in the SOFCs. (C) 2005 Springer Science + Business Media, Inc

Jitter Remains Stable throughout a Single Fiber EMG Session in Healthy and Myasthenic Muscles

Fatigability is the hallmark of myasthenia gravis (MG). It is not clear, however, whether there is an analogous increase in jitter during the course of a single fiber electromyography (SFEMG) session. The individual jitter values of all potentials of 76 normal and 44 myasthenic orbicularis oculi muscles were assigned a rank number according to their temporal order in which they were collected and linear regression was performed to determine if the slope of the regression line was significantly different from zero. Control and MG subjects displayed rather flat linear regression lines with non-significant positive or negative slopes. Accordingly, ROC analysis yielded areas under the curve near 0.5. We conclude that there is no systematic jitter increase during the collection of 20 potential pairs in a typical SFEMG session. © 2021 - IOS Press. All rights reserved

Case of Young-Onset Sporadic Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) constitutes the main type of motor neuron disease. Familial ALS is characterized by the presence of positive family history and accounts for 10% of ALS cases. Although familial ALS is the main culprit for early-onset disease, there are rare cases of early- or young-onset ALS with negative family history or sporadic ALS. We describe a 23-year-old man with clinical and electrophysiological evidence of probable sporadic ALS according to the revised EI Escorial criteria. Interestingly, brain neuroimaging revealed bilaterally increased T2 signals across corona radiata, posterior limb of the internal capsule, and descending motor tracts in the brainstem and hypointensity rim of the motor cortex on T2-weighted images. Young-onset sporadic ALS may be a distinct nosological entity. The topic is shortly discussed in the light of its genetic and clinical characteristics. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved

Mixed Conducting Oxides YxZr1-x-yTiyO2-x/2 (YZT) and Corresponding Ni/YZT Cermets as Anode Materials in SOFCs

The physical properties of mixed-conducting oxides in the ternary system Y2O3-ZrO2-TiO2 with the general formula Y (x) Zr1-x-y Ti (y) O2-x/2 (YZT, where 0.133 < x < 0.25 and 0 < y < 0.15) are presented and evaluated in terms of an application as anode materials in solid oxide fuel cells (SOFCs). The total electrical conductivity of the ceramics with cubic fluorite structure in air mainly depends on the Ti content and decreases at 900 degrees C by about one order of magnitude from y = 0 to y = 0.15. Comparing the conductivity of contributions at 900 degrees C in Ar/4% H-2 the highest contributions of electronic conductivity were obtained for y = 0.15. For the Ni/YZT cermets, the enhanced adherence at the metal/ceramic interface, compared to Ni/8YSZ (8 mol% yttria stabilised zirconia), results in a better long-term stability in terms of electrical conductivity and microstructure after 1,000 h of annealing at 1,000 degrees C in reducing atmosphere. The electrochemical performance, tested in fuel cells with Ni/8YSZ, Ni/Y0.20Zr0.75Ti0.05O1.9 and Ni/Y0.20Zr0.70Ti0.10O1.9 anodes, decreased for Ni/Y0.20Zr0.70Ti0.10O1.9 under steam reforming conditions, most likely due to the reduced ionic conductivity of this specific YZT ceramic