Search results for "defect"
showing 10 items of 879 documents
A comparison among different techniques for human ERG signals processing and classification
2014
A comparison among different techniques for human ERG signals processing and classification ( Articles not published yet, but available online Article in press About articles in press (opens in a new window) ) Barraco, R.a, Persano Adorno, D.a , Brai, M.a, Tranchina, L.b a Dipartimento di Fisica e Chimica, Università di Palermo and CNISM, Viale delle Scienze, Ed. 18, I-90128 Palermo, Italy b Laboratorio di Fisica e Tecnologie Relative - UniNetLab, Università di Palermo, Viale delle Scienze, Ed. 18, I-90128 Palermo, Italy Abstract Feature detection in biomedical signals is crucial for deepening our knowledge about the involved physiological processes. To achieve this aim, many analytic appro…
Mutations in the Cone Photoreceptor G-Protein α-Subunit Gene GNAT2 in Patients with Achromatopsia
2002
Achromatopsia is an autosomal recessively inherited visual disorder that is present from birth and that features the absence of color discrimination. We here report the identification of five independent families with achromatopsia that segregate protein-truncation mutations in the GNAT2 gene, located on chromosome 1p13. GNAT2 encodes the cone photoreceptor-specific alpha-subunit of transducin, a G-protein of the phototransduction cascade, which couples to the visual pigment(s). Our results demonstrate that GNAT2 is the third gene implicated in achromatopsia.
Incorporation of Li dopant into Cu2ZnSnSe4 photovoltaic absorber: hybrid-functional calculations
2015
We have studied the formation of Li extrinsic defects in CuZnSnSe by first-principles hybrid functional calculations. Li atoms in the Cu site (Li) and Li atoms in the Se site (Li) are the most and the least stable point defect, respectively. The formation energies of two Li interstitial defects with different numbers of nearest neighbors are the same. These interstitial point defects act as a donor but do not create gap states. Formation of the acceptor point defects (Li and Li) is less likely in p-type CuZnSnSe compared with n-type CuZnSnSe. In contrast to Li which does not create gap states, the formation of Li creates two charge transition levels in the middle of the bandgap which might …
Oral health of cystic fibrosis patients at a north american center: A pilot study
2019
Background The objective of this study was to describe the oral health status of Cystic Fibrosis (CF) children in a US facility. Material and Methods Twenty CF children ages 6-18 were recruited from Children’s Hospital of Wisconsin Pulmonary Clinic. Parents completed a health questionnaire. Clinical examinations checked dental caries using the dmft/DMFT index, dental hygiene using the Simplified Greene-Vermillion Index (DI-S), gingival inflammation using the Community Periodontal Index of Treatment Needs, and enamel defects using the modified Developmental Defects of Enamel Index. Results The majority (90%) brush twice a day, 65% consume sugary snacks, and 70% visit the dentist every 6 mont…
Adsorption of atomic and molecular oxygen on the LaMnO3(001) surface: ab initio supercell calculations and thermodynamics.
2008
We present and discuss the results of ab initio DFT plane-wave supercell calculations of the atomic and molecular oxygen adsorption and diffusion on the LaMnO(3) (001) surface which serves as a model material for a cathode of solid oxide fuel cells. The dissociative adsorption of O(2) molecules from the gas phase is energetically favorable on surface Mn ions even on a defect-free surface. The surface migration energy for adsorbed O ions is found to be quite high, 2.0 eV. We predict that the adsorbed O atoms could penetrate the electrode first plane when much more mobile surface oxygen vacancies (migration energy of 0.69 eV) approach the O ions strongly bound to the surface Mn ions. The form…
<title>Large-scale computer simulations of metal/oxide interfaces with defects</title>
2003
Ab initio slab simulations have been performed for silver adhesion to the perfect and defective MgO(001) surfaces. For 1/4 Ag monolayer (ML) coverage of perfect substrate, we observe small silver adhesion energies over both O2- and Mg2+ ions on a regular MgO(001) substrate (0.23 and 0.22 eV per Ag atom, respectively), with negligible interfacial charge transfer towards metal atoms. For larger Ag coverages (beginning with 1/2 ML), silver adsorption over regular O2- ions is much more favorable. We demonstrate that point surface defects on a magnesia surface increase markedly the metal adhesion energy and cause a redistribution of the electron density across the interface. The results for elec…
Endocarditis due to Abiotrophia defectiva, a biofilm-related infection associated with the presence of fixed braces
2017
Abstract Rationale: Endocarditis with Abiotrophia defectiva represents 4.3% to 6% of all streptococcal endocarditis. The article presents diagnosis issues and the complexity of the treatment. Patient concerns: We present the case of a female white patient, aged 26 years, who developed infectious endocarditis caused by A defectiva, in the last trimester of pregnancy, a biofilm-related infection associated with the presence of fixed braces. Diagnoses: The diagnosis of infectious endocarditis was confirmed by the cardiac ultrasound examination that revealed a voluminous vegetation on the mitral valve, and acute mitral regurgitation caused by chordae tendinae rupture, and also by isolating Abio…
Effect of aneurysm on the mechanical dissection properties of the human ascending thoracic aorta
2012
Objectives: The acute dissection of an ascending thoracic aortic aneurysm (ATAA) represents a devastating separation of elastic layers occurring when the hemodynamic loads on the diseased wall exceed the adhesive strength between layers. At present, the mechanics underlying aortic dissection are largely unclear, and the biomechanical delamination properties of the aneurysmal aorta are not defined. Individuals with bicuspid aortic valve (BAV) are particularly predisposed to ascending aortic aneurysm formation, with a marked risk of aortic dissection. The purpose of this study was to evaluate and compare the dissection properties of nonaneurysmal and aneurysmal human ascending thoracic aorta …
Cardiac Magnetic Resonance with Delayed Enhancement of the Right Ventricle in patients with Left Ventricle primary involvement: diagnosis and evaluat…
2020
: Cardiac Magnetic Resonance (CMR) allows an accurate Right Ventricle (RV) assessment that could be of great relevance in diseases causing inflammation or fibrosis. The aim of this study was to evaluate the concomitant involvement of the RV in patients with delayed enhancement (DE) of the Left Ventricle (LV-DE) using CMR. We retrospectively enrolled 95 (male n. 66; age 55±18years; BMI 26±5kg/m2) consecutive patients with LV-DE who underwent a CMR (Achieva 1.5 T, Philips) for different indications: post-ischemic dilated cardiopathy (PDM), hypertrophic cardiomyopathy (HCM), myocardial infarction (MI), myocarditis/pericarditis (MP) and congenital heart disease (CD). We assessed the presence an…
Supraventricular arrhythmias in noncompaction of left ventricle: Is this a frequent complication?
2008
Background: Isolated left ventricular noncompaction is the result of incomplete myocardial morphogenesis, leading to persistence of the embryonic myocardium. The condition is recognised by an excessively prominent trabecular meshwork and deep intertrabecular recesses of the left ventricle. Whether these intertrabecular recesses are a favorable substrate for supraventricular arrhythmias is unclear, even if the incidence of chronic heart failure seems to be high. Results: We evaluated a continuous series of 238 patients affected by noncompaction. In 4 cases the patients reported palpitations and in 4 an episode of syncope. Periodic holter monitoring was performed every 6 months for 4 years. O…