Influence of growing conditions on the reactivity of Ni supported graphene towards CO

Free standing graphene is chemically inert but, as recently demonstrated, CO chemisorption occurs at low crystal temperature on the single layer grown by ethene dehydrogenation on Ni(111). Such layer is inhomogeneous since different phases coexist, the relative abundance of which depends on the growth conditions. Here we show by X ray photoemission and high resolution electron energy loss spectroscopies that the attained CO coverage depends strongly on the relative weight of the different phases as well as on the concentration of carbon in the Ni subsurface region. Our data show that the chemical reactivity is hampered by the carbon content in the substrate. The correlation between the amount of adsorbed CO and the weight of the different graphene phases indicates that the top-fcc configuration is the most reactive

Diagnosi e terapia chirurgica degli strumi mediastinici. Rilievi su 24 casi operati

abstrac

Ferite penetranti del torace. Presentazione di 23 osservazioni

N/

Optimization of an organic memristor as an adaptive memory element

The combination of memory and signal handling characteristics of a memristor makes it a promising candidate for adaptive bioinspired information processing systems. This poses stringent requirements on the basic device, such as stability and reproducibility over a large number of training/learning cycles, and a large anisotropy in the fundamental control material parameter, in our case the electrical conductivity. In this work we report results on the improved performance of electrochemically controlled polymeric memristors, where optimization of a conducting polymer polyaniline in the active channel and better environmental control of fabrication methods led to a large increase both in the absolute values of the conductivity in the partially oxydized state of polyaniline and of the on-off conductivity ratio. These improvements are crucial for the application of the organic memristor to adaptive complex signal handling networks

Profile of deglutition speech evaluation in an intensive care unit

The combination of an increase in long-term survival and the availability of a relatively sensitive parathyroid hormone (PTH) assay has led to an increasing incidence of hyperparathyroidism (HPT) diagnosis in patients on regular dialysis treatment (RDT). Hitherto the diagnosis has been based on biochemical data and clinical grounds, as parathyroid (PT) imaging is limited in accuracy, reproducibility, safety and invasiveness [1, 2]. Today, 201TI and 99mTc subtraction imaging (sq, high resolution ultrasonography (US) and up-to-date computed tomography (CT) have been proposed as sensitive and specific tests for primary HPT imaging [4-7]. The aim of the present study was to assess on a group of patients on RDT the accuracy of these methods in relation to the degree of HP

Sostituzione valvolare e bypass aorto-coronarico combinati. Risultati immediati e tardivi di 194 casi operati

no abstrac

La terapia chirurgica del cancro bronco-polmonare. Analisi al computer di una casistica selezionata del centro di Chirurgia Toracica di Modena (328 osservazioni)

no abstrac

Di-(2-ethylhexyl) phthalate metabolites in urine show age-related changes and associations with adiposity and parameters of insulin sensitivity in childhood

Objectives: Phthalates might be implicated with obesity and insulin sensitivity. We evaluated the levels of primary and secondary metabolites of Di-(2-ethylhexyl) phthalate (DEHP) in urine in obese and normal-weight subjects both before and during puberty, and investigated their relationships with auxological parameters and indexes of insulin sensitivity. Design and Methods: DEHP metabolites (MEHP, 6-OH-MEHP, 5-oxo-MEHP, 5-OH-MEHP, and 5-CX-MEHP), were measured in urine by RP-HPLC-ESI-MS. Traditional statistical analysis and a data mining analysis using the Auto-CM analysis were able to offer an insight into the complex biological connections between the studied variables. Results: The data showed changes in DEHP metabolites in urine related with obesity, puberty, and presence of insulin resistance. Changes in urine metabolites were related with age, height and weight, waist circumference and waist to height ratio, thus to fat distribution. In addition, clear relationships in both obese and normal-weight subjects were detected among MEHP, its products of oxidation and measurements of insulin sensitivity. Conclusion: It remains to be elucidated whether exposure to phthalates per se is actually the risk factor or if the ability of the body to metabolize phthalates is actually the key point. Further studies that span from conception to elderly subjects besides further understanding of DEHP metabolism are warranted to clarify these aspects