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A fast, efficient and low-cost method for the accurate determination of local displacements in structures based on computer vision techniques is presented in this study. First, displacements at pixel level are estimated using the SURF (Speeded-Up Robust Features) image matching algorithm, which detects corresponding points in the images. Then, the initial displacement estimations are refined at subpixel scale through image cross-correlation in the frequency domain. The image acquisition is simple and fast, using a conventional low-cost digital camera. The method was validated comparing the results obtained with those provided by a high performance system (ARAMIS 5 M) that integrates two cameras and image processing software. Results show that the proposed method is able to detect displacements with a precision of approximately 60% of the pixel size. The algorithm was implemented in a computer program in order to automatize the procedure. • Estimation of displacements in structures by using a standard digital camera and DIC. • Development and use of algorithms of image matching and cross-correlation. • The hybrid SURF-DIC algorithm developed allows obtaining a precision around 60% of the pixel size. • A precision of 0.03 mm at a distance camera-object of 80 cm has been reached. • Comparison of the results with that obtained by commercial packages (ARAMIS-GOM). [ABSTRACT FROM AUTHOR]

Abstract: Spherical cells in the anteroventral division of the cochlear nucleus, which relay excitatory inputs from the auditory nerve, also receive both GABAergic and glycinergic inhibitory synapses. Inhibition mediated by GABA and glycine fulfils essential roles in the processing abilities of these and other auditory neurons. However, the developmental program leading to a mature complement of GABAergic and glycinergic synapses and microcircuits is largely unknown. Because of their relatively simple geometry, spherical cells provide an excellent model for unraveling basic developmental patterns of inhibitory synaptogenesis. Using a combination of high resolution immunocytochemical methods, we report that, in the rat, synapses containing GABA or glycine are deployed on spherical cell bodies over a time period extending well beyond hearing onset. Such postnatal developmental recruitment of inhibitory endings is progressive, although there are two distinct leaps in their numbers. The first occurs by the end of the first postnatal week, prior to hearing onset, and the second, during the third postnatal week, after hearing onset. This pattern suggests that adjustments in inhibition could be driven by acoustic experience. While GABAergic and glycinergic endings are maturing and growing in number and size, their neurotransmitter content also appears to be developmentally regulated. Quantitative ultrastructural immunocytochemistry with colloidal gold suggests that GABA and glycine accumulation in synaptic endings follows a staggered pattern, with labeling stabilizing at adult levels by postnatal day 21. This may account for adjustments in synaptic efficacy and strength. [Copyright &y& Elsevier]

Abstract: In the present work the photocatalytic and biological degradation of two commercial mixtures of pesticides (Folimat and Ronstar) and two fungicides (pyrimethanil and triadimenol) has been studied. The evolution of some components of these commercial products (dicofol, tetradifon and oxadiazon) and that of the two fungicides has been monitored by means of HPLC, GC–MS, TOC and toxicity (Lemna minor toxicity test) measurements. The photocatalytic method was able to degrade dicofol, tetradifon, pyrimethanil, triadimenol and the components of Ronstar with the exception of oxadiazon. In addition to this, the photocatalytic method eliminated pyrimethanil toxicity and reduced that of triadimenol by a 90%, Ronstar by a 78% and Folimat by an 87%. Nevertheless, the wetland reactors alone could reduce the toxicity of only the former. Finally, the proper dosage of the water containing the pesticides to a photocatalytic reactor followed by a wetland reactor resulted to be the most successful strategy for the detoxification of the studied compounds and their mixtures. [Copyright &y& Elsevier]

In this paper the degradation of gaseous alcohols (methanol, ethanol, 1-propanol and 1-butanol) has been studied in a continuous reaction system. Methanol and ethanol, but not 1-propanol and 1-butanol, have caused the catalyst bare-TiO2 to become deactivated. The catalyst containing activated carbon, AC-TiO2, has not shown almost deactivation in any experiment.To explain this behaviour variation, a thorough FTIR study concerning the interaction of gaseous alcohols with the catalyst surface and the effect of light on the process was performed. Thus, the interaction of the different catalysts with the selected alcohols, the formed species and the hydroxyl group evolution under irradiation was studied. [Copyright &y& Elsevier]

Highlights • New case of congenital myasthenic syndrome type 20. Only 8 patients published. • New mutations not described previously, • Very severe form of disease, and poor response to therapy; diagnosis achieved early by repetitive stimulation. Abstract Congenital myasthenic syndromes are a group of genetically determined rare diseases resulting from ultrastructural alterations in synaptic proteins. Up to 32 genes are known to be involved in those syndromes and many mutations have been reported, of which less than 8% affect the presynaptic complex. One of these syndromes is caused by the impairment of the presynaptic sodium-dependent high-affinity choline transporter 1, as a result of a mutation of the SCL5A7 gene associated with congenital myasthenic syndrome type 20 (MIM # 617143). We present a new case of this syndrome, caused by a mutation not previously described. A full term infant presented with acute respiratory failure and generalized weakness. The genetic analysis revealed the patient to be compound heterozygous for a new mutation of the SCL5A7 gene. The genetic analysis of congenital myasthenic syndromes provide information on the ultrastructural underlying mechanisms, which is valuable for differential diagnosis and specific treatments. [ABSTRACT FROM AUTHOR]

Abstract: In many quartzitic slopes in the NW of the Iberian Peninsula there is a high topsoil stoniness which produces a random surface roughness. The surface roughness is one of the control parameters in the signal of Synthetic Aperture Radar (SAR) images. In this work we test the use of the SAR images for distinguishing and mapping areas with different surface roughness which, in this study, correspond with areas with different surface stoniness. In accordance with the geographic location, the relief of the study area and the aims of the project JERS and ENVISAT SAR images were used. The images are characterized by the high view angles, between 33° and 42°, alternating polarization (HH/HV, VV/VH) data and ascending and descending passes. In order to describe the soil roughness various measuring methods were applied in plot parcels (direct measurements of height of clasts and laser scanning) and different roughness models were tested. The results show that there are relation between SAR signal (DN) and the soil roughness classes: DN = aθ b and the b parameter is correlated with the roughness. The best fit between roughness model and SAR data was found for mean standard deviation (rms) height of clasts. Once verified that the correlation between SAR signal and surface roughness exists, the ENVISAT images were classified into three successive surface roughness classes. In order to facilitate the classification Principal Components Analysis were carried out over all polarization bands and the object oriented classification was applied. To validate the accuracy of the SAR images classification we elaborated by photointerpretation a surface condition map for an area of 10,700 ha. The SAR classification and photointerpreted map were compared for three classes: surface without stones, surface with stones (low and medium stoniness) and total cover of loose clasts. The overall coincidence between the maps is about 70%. Besides, large areas located in the northwest of the Iberian Peninsula suffer soil degradation caused by wildfires and the increase of surface stoniness is one of the effects described in the postfire erosion. The influence of wildfires and the associated erosion is particularly important on quartzitic slopes partially covered by coarse grain-supported deposits, like the ones considered in this study. The available data for the area of study suggest the high correlation between the different classes of surface roughness and stoniness obtained from SAR imagery, and the gradual different status of postfire soil erosion. [Copyright &y& Elsevier]