Publications by authors named "Ferre D"

Metal promotion in heterogeneous catalysis requires nanoscale-precision architectures to attain maximized and durable benefits. Herein, we unravel the complex interplay between nanostructure and product selectivity of nickel-promoted InO in CO hydrogenation to methanol through in-depth characterization, theoretical simulations, and kinetic analyses. Up to 10 wt.

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External antiparasitic agents applied in bovine production represent a risk to consumers of meat products, especially if the conditions of their use are not strictly respected. The post-mortem control of residues in meat is an activity that must be updated and reinforced by the biomonitoring of live animals and the use of analytical tools to help identifying signs of early warning risks. The objective of the present study was to carry out a pre-slaughter biomonitoring approach in Aberdeen Angus cattle and crosses (n = 12) with the application of a commercial formulation of cypermethrin plus chlorpyrifos.

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Cypermethrin (CYP) and chlorpyrifos (CPF) are insecticides/parasiticides used in the production of fruits, vegetables and beef cattle. These substances or their metabolites are frequently reported as residues in food, whose consumption in a diet implies a genotoxic risk. The potential for chronic toxicity of CYP and CPF is unclear, and only a few genotoxicological evaluations based on their mixture have been performed.

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Chlorpyrifos is an anticholinesterase organophosphate insecticide widely used in Argentina in the production of food derived from animal, fruit and horticultural origin and is reported as a residue within these products. Local reference values for acetyl and butyrylcholinesterase were determined in Aberdeen Angus bovine and cross bred cattle (n = 25), a requirement to be able to evaluate toxicity of commercial organophosphate and carbamate formulations. The activity of cholinesterase enzymes presented an overall mean of 2,183.

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Higher alcohols are important compounds with widespread applications in the chemical, pharmaceutical and energy sectors. Currently, they are mainly produced by sugar fermentation (ethanol and isobutanol) or hydration of petroleum-derived alkenes (heavier alcohols), but their direct synthesis from syngas (CO + H) would comprise a more environmentally-friendly, versatile and economical alternative. Research efforts in this reaction, initiated in the 1930s, have fluctuated along with the oil price and have considerably increased in the last decade due to the interest to exploit shale gas and renewable resources to obtain the gaseous feedstock.

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Birds have the potential to be considered valuable bioindicators of the quality of ecosystems and the environmental impact of pollutants. The aims of this study were to determine the micronuclei frequency and other nuclear abnormalities in erythrocytes by analyzing a wild bird community from central Monte desert (Argentina) and to clarify if there were any differences among certain species. Frequencies of nuclear abnormalities were determined in 73 wild birds belonging to 17 species and two orders (Passeriformes and Columbiformes).

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The thermodynamics and kinetics of the surface hydrogenation of adsorbed atomic carbon to methane, following the reaction sequence C+4H(-->/<--)CH+3H(-->/<--)CH(2)+2H(-->/<--)CH(3)+H(-->/<--)CH(4), are studied on Fe(100) by means of density functional theory. An assessment is made on whether the adsorption energies and overall energy profile are affected when zero-point energy (ZPE) corrections are included. The C, CH and CH(2) species are most stable at the fourfold hollow site, while CH(3) prefers the twofold bridge site.

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The formation of water by hydrogenation of atomic oxygen is studied using density functional theory. Atomic oxygen preferentially adsorbs at the four-fold hollow site, the hydroxyl group prefers the bridge site in a tilted configuration, and water is most stable when adsorbed at the top site with the two O-H bonds parallel to the Fe surface. Water formation by the hydrogenation of oxygen is a highly activated process on the Fe(100) surface, with similar activation energies, in the order of 1.

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Background: The low infectious dose and multiple transmission routes favour the appearance of norovirus outbreaks. The objective of this study was to compare the incidence of norovirus outbreaks in hospitals and nursing homes in Catalonia.

Methods: A descriptive study of norovirus outbreaks between 15/10/2004 and 30/10/2005 was carried out.

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The dynamics of the Earth's interior is largely controlled by mantle convection, which transports radiogenic and primordial heat towards the surface. Slow stirring of the deep mantle is achieved in the solid state through high-temperature creep of rocks, which are dominated by the mineral MgSiO3 perovskite. Transformation of MgSiO3 to a 'post-perovskite' phase may explain the peculiarities of the lowermost mantle, such as the observed seismic anisotropy, but the mechanical properties of these mineralogical phases are largely unknown.

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In the present article, we report adsorption energies, structures, and vibrational frequencies of CO on Fe(100) for several adsorption states and at three surface coverages. We have performed a full analysis of the vibrational frequencies of CO, thus determining what structures are stable adsorption states and characterizing the transition-state structure for CO dissociation. We have calculated the activation energy of dissociation of CO at 0.

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Parallel cytophotometric ploidy studies and cytogenetic analysis were performed on 15 various human solid tumours. The quantification of DNA by image analysis was carried out on cytological imprints of fresh tumours and on smears obtained after cell culture. The results obtained by both sets of calculations were compared with each other and with the cytogenetic results.

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The cytogenetic analysis of 67 meningiomas (58 intracranial and 9 spinal tumors) identified chromosomal abnormalities in 63% of cases. When chromosomes involved in numerical and structural changes with a frequency of more than one standard deviation above the mean were considered, distinct cytogenetic patterns could be identified according to sex, anatomical location and histology. The chromosomes more frequently affected were 1, 2, 3, 4, 8, 14, 15, 19, 22, Y.

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To assess the effect of a single chromosomal translocation on the nuclear phenotype of human cells, seven diploid adenomas and five diploid carcinomas of the thyroid gland were studied using quantitative nuclear morphometry. Four adenomas and three carcinomas were cytogenetically normal, whereas three adenomas and two carcinomas had a unique chromosomal translocation. A densitometric parameter discriminated adenomas from carcinomas (skewness of the optical density histogram, SODH), and tumours with and without chromosomal translocation (standard deviation of the optical density, SDODH).

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The distribution of 271 chromosomal breakpoints involved in 203 clonal structural non "specific" rearrangements identified in 82 human primary solid tumors of various histologies has been analyzed. According to the "mean + 1 SD" criterion the normalized breakpoint frequency was significantly higher for chromosomes 1p, 3p, 3q, 4q, 6q, 7q, and 11p. Clusters of 3 or more breakpoints were assigned to only 24 of the 329 bands (7%) of the standard karyotype, and 9 high density breakpoint segments have been identified.

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A cytogenetic study was performed in 63 thyroid tumors after a monolayer short-term culture. Clonal chromosomal changes were found in 47% of carcinomas and 31% of adenomas. Chromosome 7 was altered in 40% of cytogenetically abnormal tumors.

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A cytogenetic study was performed in 18 renal cell carcinomas using a culture method previously described. The significance of chromosome involvement in clonal aberrations was evaluated according to the mean + 1 SD objective criterion. Chromosomes 3, 7, 9, and 17 were preferentially involved in both numerical and structural changes.

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A cytogenetic analysis has been performed on 109 non-malignant human solid tumors of various histological types after short-term culture. These tumors were derived from epithelial, mesenchymal, embryonal and neurogenic tissues. The chromosome count was in the diploid range in virtually all specimens.

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Four resistant sublines were derived from the sensitive human ovarian carcinoma IGROV 1 (OV1-P) cell line by exposure to increasing concentrations of vincristine, doxorubicin, and cisplatinum. The vincristine-resistant sublines expressed the MDR phenotype associated with a complete reversion of malignant properties. Cytogenetic studies of sensitive and resistant cells have been repeatedly performed over a 1-year period.

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A cytogenetic study performed on 6 human renal cell carcinomas after short-term culture on extracellular matrix with serum-free medium showed aneuploidy without structural changes in 2 tumors and a rearrangement of the short arm of chromosome 3 in 4 tumors, including deletions and a translocation involving the 3p14 and 3p21 bands. Chromosomal in situ hybridization with a c-raf 1 probe demonstrated that in 2 renal cancers with del3(p14 or 21) the cellular oncogene had shifted from 3p25 to 3p14 as a result of an interstitial deletion.

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The mixed antiglobulin reaction (MAR) test for immunoglobulins G was performed on 574 spermograms, resulting in the detection of surface auto-antibodies directed against spermatozoa in 4.18% of the cases. Concomitant investigations of spermograms for spontaneous agglutination and cross-penetration in a control cervical mucus, together with assays of antispermatozoa antibodies in serum and seminal fluid, have led to the diagnosis of asthenospermia in 87.

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The present knowledge of the physiology of H-Y antigen has been reviewed. It would appear that the results that have been obtained contradict one another and this brings into doubt the role that this antigen plays in testicular differentiation and the link it has with the Y chromosome.

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