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Cortico-cortical evoked potentials (CCEPs) recorded by stereo-electroencephalography (SEEG) are a valuable tool to investigate brain reactivity and effective connectivity. However, invasive recordings are spatially sparse since they depend on clinical needs. This sparsity hampers systematic comparisons across-subjects, the detection of the whole-brain effects of intracortical stimulation, as well as their relationships to the EEG responses evoked by non-invasive stimuli. To demonstrate that CCEPs recorded by high-density electroencephalography (hd-EEG) provide additional information with respect SEEG alone and to provide an open, curated dataset to allow for further exploration of their potential. The dataset encompasses SEEG and hd-EEG recordings simultaneously acquired during Single Pulse Electrical Stimulation (SPES) in drug-resistant epileptic patients (N = 36) in whom stimulations were delivered with different physical, geometrical, and topological parameters. Differences in CCEPs were assessed by amplitude, latency, and spectral measures. While invasively and non-invasively recorded CCEPs were generally correlated, differences in pulse duration, angle and stimulated cortical area were better captured by hd-EEG. Further, intracranial stimulation evoked site-specific hd-EEG responses that reproduced the spectral features of EEG responses to transcranial magnetic stimulation (TMS). Notably, SPES, albeit unperceived by subjects, elicited scalp responses that were up to one order of magnitude larger than the responses typically evoked by sensory stimulation in awake humans. CCEPs can be simultaneously recorded with SEEG and hd-EEG and the latter provides a reliable descriptor of the effects of SPES as well as a common reference to compare the whole-brain effects of intracortical stimulation to those of non-invasive transcranial or sensory stimulations in humans. • CCEPs recorded with hd-EEG and SEEG are correlated. • hd-EEG recording is highly sensitive to changes in stimulation parameters. • Hd-EEG responses to SPES are characterized by site-specific mean frequencies. • hd-EEG responses to SPES are larger than typical sensory evoked potentials. • An open dataset of simultaneous hd-EEG and SEEG during SPES is provided. [ABSTRACT FROM AUTHOR]

Abstract: By electrodeposition it is possible to obtain alloy phases of metastable structure; these phases may be different from those reported for metallurgical equilibrium conditions or may have different compositions for the solubility limits, in some cases with very important enlargement. Typical cases are examined, discussing published results and presenting new findings. To understand the general behaviour, free energy versus composition g/x diagrams were calculated and are presented for the alloys examined in equilibrium conditions and after modification to obtain composition limits for the electrodeposited phases in stable and metastable state. The first reported case is Ni–Sn alloy, where the well known metastable phase NiSn is obtained. The second case is the electrodeposition of IB–Sn alloys from non-cyanide electrolytes. Phase structure of Zn-rich electrodeposited Zn–Ni alloys is also discussed as representative of grain size effect on phase stability. From the different cases examined, the occurrence of electrodeposited intermediate phases can be interpreted according to a local thermodynamic equilibrium, whilst long range order is difficult to observe in as-deposited layers. These phases depend on bath composition and operation conditions (temperature, stirring, direct or pulse current density) giving phases of different grain size which in turn can influence their stability. [Copyright &y& Elsevier]

Abstract In this work, the electrodeposition of zinc is carried out from a chlorides-free organic solution based on ethylene glycol (EG) and acetate precursor salts. The formation of an EG-complex with zinc was observed through 1H NMR. The electrochemical characterization was performed by means of cyclic voltammetry (CV) and linear sweep voltammetry (LSV) on platinum and steel respectively. Electrodeposition was investigated with both potentiostatic (from −1 V vs Pt to −2 V vs Pt) and galvanostatic (from −2 mA/cm2 to −16 mA/cm2) approaches together with Hull cell test: cathodic efficiencies > 85% were reported. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses showed that the films were compact, with large grains and a hexagonal microstructure preferentially oriented along the [002]/[102] directions. The high purity of the deposits was assessed by electron dispersive spectroscopy (EDS). Polarization tests in de-aerated 5 %wt NaCl solution resulted in a corrosion potential of E corr = −1.03 V vs Ag/AgCl (I corr = 1.01 × 10−6 A/cm2). [ABSTRACT FROM AUTHOR]

Idiopathic scoliosis (IS) is an abnormality of the vertebral column with a spine curvature of at least 10 degrees. It is the most common spinal deformity in children with a prevalence of 2%–3%, and its aetiology is unknown. Genetic factors are known to play a role and a number of linkage analyses showed associations of various loci. Here we describe a new case of a de novo interstitial deletion 8q11.21q11.2 disrupting SNTG1 gene, identified by array-CGH in a girl with cognitive impairment and a scoliosis that 'appears' like to IS. SNTG1 encodes γ-1 Syntrophin protein that is part of the dystrophin associated protein complex and interacts directly with the C-terminal of dystrophin. Its expression is restricted to neurons and particularly in those areas of the brain that have been suggested to affect postural control. The involvement of SNTG1 gene in IS was already been reported in a family with a breakpoint between exons 10 and 11. Mutational analysis of SNTG1 exons in 152 sporadic IS patients had revealed changes in three patients. In conclusion, our data add a further line of evidence suggesting SNTG1 could represent an interesting candidate for its involvement in scoliosis. • Idiopathic scoliosis (IS) is a vertebral column spinal deformity in children with a prevalence of 2%-3%. • The aetiology of IS is unknown. Genetic factors are known to play a role. • Here we describe a case of a de novo interstitial deletion 8q11.21q11.2 disrupting SNTG1 gene in a girl with IS and cognitive impairment. • SNTG1 encodes γ-1 Syntrophin protein, is expressed in neurons and particularly in brain areas that affect postural control. [ABSTRACT FROM AUTHOR]