The fabrication of sponge-like vanadium pentoxide (VO) nanostructures using vertically aligned carbon nanotubes (VACNTs) as a template is presented. The VACNTs were grown on silicon substrates by chemical vapor deposition using the Fe/Al bilayer catalyst approach. The VO nanostructures were obtained from the thermal oxidation of metallic vanadium deposited on the VACNTs.
View Article and Find Full Text PDFThe chiral-induced spin selectivity effect (CISS) is a breakthrough phenomenon that has revolutionized the field of electrocatalysis. We report the first study on the electron spin-dependent electrocatalysis for the oxygen reduction reaction, ORR, using iron phthalocyanine, FePc, a well-known molecular catalyst for this reaction. The FePc complex belongs to the non-precious catalysts group, whose active site, FeN4, emulates catalytic centers of biocatalysts such as Cytochrome c.
View Article and Find Full Text PDFLithium iron phosphate (LiFePO, LFP) is the most promising cathode material for use in safe electric vehicles (EVs), due to its long cycle stability, low cost, and low toxicity, but it suffers from low conductivity and ion diffusion. In this work, we present a simple method to obtain LFP/carbon (LFP/C) composites with different types of NC: cellulose nanocrystal (CNC) and cellulose nanofiber (CNF). Microwave-assisted hydrothermal synthesis was used to obtain LFP with nanocellulose inside the vessel, and the final LFP/C composite was achieved by heating the mixture under a N atmosphere.
View Article and Find Full Text PDFPerchlorate has been described as an emerging pollutant that compromises water sources and human health. In this study, a new electrotrophic perchlorate reducing microorganism (EPRM) isolated from the Atacama Desert, Dechloromonas sp. CS-1, was evaluated for perchlorate removal in water in a bioelectrochemical reactor (BER) with a chemically modified electrode.
View Article and Find Full Text PDFThe development of photoelectrode materials for efficient water splitting using solar energy is a crucial research topic for green hydrogen production. These materials need to be abundant, fabricated on a large scale, and at low cost. In this context, hematite is a promising material that has been widely studied.
View Article and Find Full Text PDFHighly ordered nanostructure arrays have attracted wide attention due to their wide range of applicability, particularly in fabricating devices containing scalable and controllable junctions. In this work, highly ordered carbon nanotube (CNT) arrays grown directly on Si substrates were fabricated, and their electronic transport properties as a function of wall thickness were explored. The CNTs were synthesized by chemical vapor deposition inside porous alumina membranes, previously fabricated on n-type Si substrates.
View Article and Find Full Text PDFNowadays, green hydrogen is an important niche of interest in which the search for a suitable composite material is indispensable. In this sense, titanium oxide nanotubes (TiO nanotube, TNTs) were prepared from double anodic oxidation of Ti foil in ethylene glycol electrolyte. The morphology of the nanotubes was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD).
View Article and Find Full Text PDFNickel nanopillar arrays were electrodeposited onto silicon substrates using porous alumina membranes as a template. The characterization of the samples was done by scanning electron microscopy, X-ray diffraction, and alternating force gradient magnetometry. Ni nanostructures were directly grown on Si by galvanostatic and potentiostatic electrodeposition techniques in three remarkable charge transfer configurations.
View Article and Find Full Text PDFFamilial hypercholesterolemia (FH) is an underdiagnosed genetic inherited condition that may lead to premature coronary artery disease (CAD). FH has an estimated prevalence in the general population of about 1:313. However, its prevalence in patients with premature STEMI (ST-elevation myocardial infarction) has not been widely studied.
View Article and Find Full Text PDFThe nuclear-factor kappa-beta (NF-KB) is a driver of inflammation, and plays an important role in the pathogenesis of atherosclerosis and coronary artery disease (CAD). Early-onset CAD is defined as a coronary ischaemic episode at an age ≤55 years, and in our population was strongly associated with male sex and smoking. Our aim was to determine whether common variants in three NF-KB genes were associated with early-onset CAD.
View Article and Find Full Text PDFAims: The role of high-intensity exercise and other emerging risk factors in lone atrial fibrillation (Ln-AF) epidemiology is still under debate. The aim of this study was to analyse the contribution of each of the emerging risk factors and the impact of physical activity dose in patients with Ln-AF.
Methods And Results: Patients with Ln-AF and age- and sex-matched healthy controls were included in a 2:1 prospective case-control study.
The hybrid structures composed of gold nanoparticles and carbon nanotubes were prepared using porous alumina membranes as templates. Carbon nanotubes were synthesized inside the pores of these templates by the non-catalytic decomposition of acetylene. The inner cavity of the supported tubes was used as nanoreactors to grow gold particles by impregnation with a gold salt, followed by a calcination-reduction process.
View Article and Find Full Text PDFHybrid nanostructured arrays based on carbon nanotubes (CNT) and palladium or titanium dioxide materials have been synthesized using self-supported and silicon-supported anodized aluminum oxide (AAO) as nanoporous template. It is well demonstrated that carbon nanotubes can be grown using these membranes and hydrocarbon precursors that decompose at temperatures closer to 600°C without the use of a metal catalyst. In this process, carbonic fragments condensate to form stacked graphitic sheets, which adopt the shape of the pores, yielding from these moulds' multi-walled carbon nanotubes.
View Article and Find Full Text PDFCarbon nanostructures were synthesized by decomposition of different carbon sources over an alumina supported palladium catalyst via Chemical Vapor Deposition (CVD). Several experimental conditions were varied to verify their influence in the synthesis products: temperature ramping rate, pre-annealing conditions, hydrogen pre-treatment, synthesis temperature and time, together with the use of different carbon sources. Depending on the experimental conditions carbon nanotubes and nanofibers with different shapes and structural characteristics were obtained.
View Article and Find Full Text PDFA 18-year-old boy presented for cardiological evaluation for a previous pleuritic chest pain. Physical exam was normal and ECG showed an early repolarization pattern. Transthoracic echocardiogram revealed an ondulating structure on the left side of the interatrial septum (IAS), without other abnormalities.
View Article and Find Full Text PDFAims: The beneficial effect of specific measures in patients with newly detected diabetes during percutaneous coronary intervention (PCI) has been poorly studied. Here, we determined the prevalence of newly detected diabetes in a cohort of patients who underwent PCI and analysed their clinical outcome.
Methods And Results: A prospective study included patients without previous diagnosis of diabetes that were referred for PCI between November 2005 and May 2006.
We report the case of a 57-year-old man who underwent orthotopic heart transplantation because of prior myocardial infarction and cardiogenic shock. The patient developed refractory hypoxemia 7 months after transplantation, secondary to a right to left shunt across a patent foramen ovale related to severe tricuspid regurgitation resulting from repeated control biopsies. Percutaneous closure of the foramen ovale was performed.
View Article and Find Full Text PDFCarbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from the pyrolytic decomposition of Iron Phthalocyanine (FePc) molecules, on SiO2/Si(111) substrates in the presence of a hydrogen flow. FePc molecules contribute simultaneously both to the formation of the precursor Fe nanoparticles and also as a Carbon source. Different experimental conditions were examined.
View Article and Find Full Text PDFEndovascular treatment of thoracic aortic pathology has become a valuable alternative therapeutic option to open surgery, however complications both during implantation and the postoperative period may occur. In this case report we present an intimal dehiscence during endovascular procedure. Diagnosis was made by transoesophageal echocardiography.
View Article and Find Full Text PDFIn Argentina there are no values regarding the content selenium in food or its effect on nutritional status. Neutron activation analysis and a radiochemical separation scheme for selenium has been adjusted for blood samples from healthy adult individuals. Fasting whole blood was collected, lyophilized, packed, and irradiated in a nuclear reactor.
View Article and Find Full Text PDFDNA polymorphisms at the endothelium constitutive nitric oxide synthase gene (NOS3) have been linked to the risk of developing coronary artery disease (CAD). In vitro, a polymorphism in the 5' region of the NOS3 gene (-786 T/C) influences promoter activity. This polymorphism has been associated with coronary spasms among Japanese.
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