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In this work, a methodology of synthesis was designed to obtain ZnO nanoparticles (ZnO NPs) in a controlled and reproducible manner. The nanoparticles obtained were characterized using infrared spectroscopy, X-ray diffraction, and transmission electron microscopy (TEM). Also, we determined the antifungal capacity in vitro of zinc oxide nanoparticles synthesized, examining their action on Erythricium salmonicolor fungy causal of pink disease. To determine the effect of the quantity of zinc precursor used during ZnO NPs synthesis on the antifungal capacity, 0.1 and 0.15 M concentrations of zinc acetate were examined. To study the inactivation of the mycelial growth of the fungus, different concentrations of ZnO NPs of the two types of synthesized samples were used. The inhibitory effect on the growth of the fungus was determined by measuring the growth area as a function of time. The morphological change was observed with high-resolution optical microscopy (HROM), while TEM was used to observe changes in its ultrastructure. The results showed that a concentration of 9 mmol L-1 for the sample obtained from the 0.15 M and at 12 mmol L-1 for the 0.1 M system significantly inhibited growth of E. salmonicolor. In the HROM images a deformation was observed in the growth pattern: notable thinning of the fibers of the hyphae and a clumping tendency. The TEM images showed a liquefaction of the cytoplasmic content, making it less electron-dense, with the presence of a number of vacuoles and significant detachment of the cell wall. [ABSTRACT FROM AUTHOR]

A single Ra ion stored in a Paul radio frequency ion trap has excellent potential for a precision measurement of the electroweak mixing angle at low momentum transfer and as the most stable optical clock. The effective transport and cooling of singly charged ions of the isotopes Ra to Ra in a gas filled radio frequency quadrupole device is reported. The absolute frequencies of the transition 7sS-7dD at wavelength 828 nm have been determined in Ra with ≤19 MHz uncertainty using laser spectroscopy on small samples of ions trapped in a linear Paul trap at the online facility Trapped Radioactive Isotopes: µicrolaboratories for fundamental Physics (TRIµP) of the Kernfysisch Versneller Instituut. [ABSTRACT FROM AUTHOR]

This paper explores the changes in value added (VA) of a sample of schools for cohorts of students finishing secondary education between 2005 and 2008. VA estimates are based on distance measures obtained from DEA models. These measures are computed for each pupil in each school, and evaluate the distance between the school frontier in a given year and a pooled frontier comprising all schools analysed. The school VA is then computed by aggregating the VA scores for the cohort of pupils attending that school in a given year. The ratio between VA estimates for two consecutive cohorts, that attended the school in different years, is taken as the index of VA change. However, the evolution of school performance over time should consider not only the movements of the school frontier, but should also take into account other effects, such as the proximity of the students to the best-practices, represented by the school frontier, observed over time. For that purpose we developed an enhanced Malmquist index to evaluate the evolution of school performance over time. One of the components of the Malmquist index proposed measures VA change, and the other measures the ability of all school students to move closer to their own school best practices over time. The approach developed is applied to a sample of Portuguese secondary schools. [ABSTRACT FROM AUTHOR]

Onychomycosis is a common fungal infection of the nail but few data of mycological features in geriatric Portuguese population are yet available. The aim of this study was to perform a mycological examination and characterization of fungal nail pattern of a geriatric population from the north of Portugal clinically suspected of onychomycosis. A total of 108 patients attending the Podology Service in the Centro Hospitalar do Alto Ave (Portugal) from October 2007 to January 2009 were enrolled. All were suspected of having onychomycosis by the abnormal appearance of their nails. From these, 59.3% were diabetic. Distal and lateral subungual onychomycosis was the more common clinical pattern followed by total dystrophic onychomycosis. In 21.3% cases, every nail in both feet had an abnormal appearance. In 86%, the hallux was involved in at least one foot. Fifty samples were culture positive, and fifty-four isolates were reported regardless of the questionable pathogenicity of the infectious agent. In three cases, clinical feature of the nail, direct microscopy, and culture were consistent with Scopulariopsis infection . Fusarium spp . were identified in three cases; however, only one isolate was preceded by the observation of branching septate filaments by direct microscopy. No mixed infections with dermatophytes were reported. Trichophyton rubrum was the dermatophyte most frequently isolated (83.3%) followed by Trichophyton interdigitale. In Portugal, onychomycosis is still viewed by general population as a cosmetic condition. Health risk is enhanced in geriatrics that only perceived the severity of their condition when experiencing further foot complications that include bacterial infection and pain. [ABSTRACT FROM AUTHOR]

The patched (PTCH) mutation rate in nevoid basal cell carcinoma syndrome (NBCCS) reported in various studies ranges from 40 to 80%. However, few studies have investigated the role of PTCH in clinical conditions suggesting an inherited predisposition to basal cell carcinoma (BCC), although it has been suggested that PTCH polymorphisms could predispose to multiple BCC (MBCC). In this study, we therefore performed an exhaustive analysis of PTCH (mutations detection and deletion analysis) in 17 patients with the full complement of criteria for NBCCS (14 sporadic and three familial cases), and in 48 patients suspected of having a genetic predisposition to BCC (MBCC and/or age at diagnosis < or =40 years and/or familial BCC). Eleven new germline alterations of the PTCH gene were characterised in 12 out of 17 patients harbouring the full complement of criteria for the syndrome (70%). These were frameshift mutations in five patients, nonsense mutations in five patients, a small inframe deletion in one patient, and a large germline deletion in another patient. Only one missense mutation (G774R) was found, and this was in a patient affected with MBCC, but without any other NBCCS criterion. We therefore suggest that patients harbouring the full complement of NBCCS criteria should as a priority be screened for PTCH mutations by sequencing, followed by a deletion analysis if no mutation is detected. In other clinical situations that suggest genetic predisposition to BCC, germline mutations of PTCH are not common. [ABSTRACT FROM AUTHOR]

The purpose of this study was to quantify in vivo the impact of different dietary Ca contents on the maternal total skeleton and skeletal sub-areas in adult rats during pregnancy and lactation, using DXA. Twenty-four female Wistar rats (approximately 5 months old) were mated and divided into three groups (n = 8) and fed one of the following diets, varying only in Ca content (LCD: 0.14%, NCD: 0.6% or HCD: 1.2%). Pups were adjusted to 8–9 per dam. Maternal ionic calcium and in vivo bone mineral density (BMD) were measured at the beginning, after delivery and after weaning. Regardless of the diet, ionized calcium decreased from onset to weaning (P < 0.05). At weaning, bone mass decreased 7.3% in NCD, 15% in LCD and 10.5% in HCD from initial values. Total skeleton, whole and proximal tibia and spine BMDs only decreased at delivery in the LCD group (P < 0.05) but, irrespective of the diet, at weaning, they were lower compared to delivery and initial values (P < 0.05). LCD group presented the lowest BMD in the proximal tibia and spine regions (P < 0.05). At birth, pups did not present differences, however, at weaning, LCD pups reached the lowest body weight (P < 0.05), NCD presented the highest body Ca content (P < 0.05) and there were no differences between LCD and HCD. This in vivo study showed that regardless of the dietary calcium content, the maternal skeleton is slightly affected by pregnancy but severely affected by lactation. However, the degree of such response appears to depend not only on dietary Ca content but also on dietary Ca/P molar ratio. [ABSTRACT FROM AUTHOR]

The acid-base properties of several NiMoO catalysts supported on two silicas and prepared by different methods have been studied by temperature-programmed desorption of NH. The catalytic behavior in the oxidative dehydrogenation of isobutane for two NiMoO catalysts with different acid-base properties are compared. [ABSTRACT FROM AUTHOR]

Splenic autotransplantation seems to be the only alternative for preservation of splenic tissue after total splenectomy. This work was carried out to analyze the morphologic regeneration of autotransplanted splenic tissue in Wistar rats and to determine the bacterial phagocytic function of their macrophages. We utilized an experimental model including young and adult rats, of both sexes, submitted to total splenectomy combined with autotransplantation in the greater omentum of slices of the whole mass of spleen. Sixteen weeks later animals were intravenously inoculated with a suspension of Escherichia coli AB1157. There was regeneration of autotransplanted splenic tissue in all animals. A similar morphological aspect among all animals was observed, with splenic tissue showing red and white pulps with a moderate architectural disarrangement. Macrophages containing bacterial aggregates were observed, as well as macrophages with hemosiderin pigments inside the cytoplasm. Blood vessels showed preserved walls, with no signs of vasculitis or thrombosis. The present results suggest that splenic autotransplants in the greater omentum of the rat acquire the macro- and microscopic architecture of a normal spleen, with reduced dimensions, and preserve bacterial phagocyte function. [ABSTRACT FROM AUTHOR]

The behaviour of the oxidative dehydrogenation and isomerization reactions of 1-butene, cis-2-butene and trans-2-butene in the presence of oxygen over bismuth molybdates is studied. The significant observed differences are interpretable in the light of the site isolation concept, taking into account the pronounced different reduction power of the tested olefins. Important aspects of the mechanisms of the involved reactions are discussed. [ABSTRACT FROM AUTHOR]

The acid-base properties of a series of SiO-supported NiMoO catalysts were investigated by temperature-programmed desorption of NH and CO. Results show that supported catalysts with ca. one monolayer of the active phase are less acidic than the unsupported stoichiometric NiMoO. [ABSTRACT FROM AUTHOR]

Several 4-(aminomethylisoxazolyl)-1,2-naphthoquinones inhibited growth and DNA synthesis in Trypanosoma cruzi and stimulated O uptake and $$O_2 ^{\bar .} $$ generation by the parasite epimastigotes and their mitochondrial and microsomal membranes; these results support the idea that oxygen radicals play a role in quinone toxicity. Maximal effects on respiration and $$O_2 ^{\bar .} $$ generation were observed with antimycin-inhibited cells. Similar results as well as stimulation of HO production were obtained with Crithidia fasciculata despite the presence of catalase in this organism. [ABSTRACT FROM AUTHOR]