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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]

An algorithm for automatic detection of planar and quasi-planar surfaces from Mobile Laser Scanning (MLS) data is proposed. The method uses line clouds for efficient data reduction of point clouds from MLS. The singular geometry of the MLS data on planar surfaces is used to transform the original point cloud into a more structured line cloud, which allows the simplification of the initial data and identification of surfaces by grouping lines. From each profile in the original dataset, strings of aligned points are identified, and a line cloud is defined by the endpoints of these strings. Lines are subsequently grouped following a set of parallelism, proximity and merging rules. The algorithm was tested using an urban dataset, and validated on 27 surfaces, by assessing the correctness and completeness of the point and line grouping. Correctness was, in all the surfaces, higher than 99%, and completeness was 90% on average. [ABSTRACT FROM AUTHOR]

Objective:The adjusted effect of long-chain polyunsaturated fatty acid (LCPUFA) intake during pregnancy on adiposity at birth of healthy full-term appropriate-for-gestational age neonates was evaluated.Study Design:In a cross-sectional convenience sample of 100 mother and infant dyads, LCPUFA intake during pregnancy was assessed by food frequency questionnaire with nutrient intake calculated using Food Processor Plus. Linear regression models for neonatal body composition measurements, assessed by air displacement plethysmography and anthropometry, were adjusted for maternal LCPUFA intakes, energy and macronutrient intakes, prepregnancy body mass index and gestational weight gain.Result:Positive associations between maternal docosahexaenoic acid intake and ponderal index in male offspring (β=0.165; 95% confidence interval (CI): 0.031-0.299; P=0.017), and between n-6:n-3 LCPUFA ratio intake and fat mass (β=0.021; 95% CI: 0.002-0.041; P=0.034) and percentage of fat mass (β=0.636; 95% CI: 0.125-1.147; P=0.016) in female offspring were found.Conclusion:Using a reliable validated method to assess body composition, adjusted positive associations between maternal docosahexaenoic acid intake and birth size in male offspring and between n-6:n-3 LCPUFA ratio intake and adiposity in female offspring were found, suggesting that maternal LCPUFA intake strongly influences fetal body composition. [ABSTRACT FROM AUTHOR]

Abstract: An algorithm for automatic extraction of pole-like street furniture objects using Mobile Laser Scanner data was developed and tested. The method consists in an initial simplification of the point cloud based on the regular voxelization of the space. The original point cloud is spatially discretized and a version of the point cloud whose amount of data represents 20–30% of the total is created. All the processes are carried out with the reduced version of the data, but the original point cloud is always accessible without any information loss, as each point is linked to its voxel. All the horizontal sections of the voxelized point cloud are analyzed and segmented separately. The two-dimensional fragments compatible with a section of a target pole are selected and grouped. Finally, the three-dimensional voxel representation of the detected pole-like objects is identified and the points from the original point cloud belonging to each pole-like object are extracted. The algorithm can be used with data from any Mobile Laser Scanning system, as it transforms the original point cloud and fits it into a regular grid, thus avoiding irregularities produced due to point density differences within the point cloud. The algorithm was tested in four test sites with different slopes and street shapes and features. All the target pole-like objects were detected, with the only exception of those severely occluded by large objects and some others which were either attached or too close to certain features. [Copyright &y& Elsevier]

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 study the different processes occurring on the TiO2 and Pd and Cu doped TiO2 surfaces during the photocatalytic formic acid degradation in the presence or absence of S2O82- or H2O2 have been investigated. FTIR studies have shown the relevance of the H-bounded hydroxyl groups. It has been observed that formate molecules interact simultaneously with the dopants and surfacial Ti atoms yielding an intermediate species which plays an important role in the phototacatalytic degradation mechanism. Also, it has been determined that Pd or Cu oxides may act as receptors or transmitters of the TiO2 photogenerated electrons and thus modify the degradation mechanism. Different redox reactions have been proposed according to the obtained results. [Copyright &y& Elsevier]

Ultrastructural studies of the hair follicle show that the outer root sheath (ORS) does not consist of a homogeneous cell population. The innermost cell layer of the ORS, also called the companion layer, is a single cell layer closely associated with the Henle layer of the inner root sheath.To describe the immunohistochemical expression of calretinin, a calcium-binding protein, in the human hair follicle.Immunohistochemical studies using two different antisera to calretinin were performed in paraffin-embedded and in frozen scalp specimens using standard techniques.Calretinin immunostaining was consistently and specifically found in the companion cell layer of hair follicles.These findings provide further evidence to support the notion that the companion layer is not only morphologically, but also immunohistochemically, different from the other cells of the ORS. [ABSTRACT FROM AUTHOR]

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]

Background Cranial autonomic parasympathetic symptoms (CAPS) appear in at least half of migraine patients theoretically as a result of the release of peptides by the trigemino-vascular system (TVS). Cranial pain pathways become sensitised by repeated episodes of TVS activation, leading to migraine chronification. Objective The objective of this article is to correlate the presence of CAPS with serum levels of vasoactive intestinal peptides (VIP) and calcitonin gene-related peptide (CGRP). Patients and methods Patients with chronic migraine (CM) were asked about the presence - during migraine attacks - of five CAPS, which were scored from 0 to 10 by using a quantitative scale. Serum VIP and CGRP levels were determined by ELISA. Results We interviewed 87 CM patients (82 females; mean age 44.7 ± 10.6 years). Seventeen had no CAPS, while 70 reported at least one CAPS. VIP levels ranged from 20.8 to 668.2 pg/ml (mean 154.5 ± 123.2). There was a significant positive correlation between scores in the CAPS scale and VIP levels (Spearman correlation coefficient = 0.227; p = 0.035). VIP levels were significantly higher in CM patients by at least one point in the scale vs those with 0 points ( p = 0.002). Analysing symptoms individually, VIP levels were numerically higher in those patients with symptoms, though they were significantly higher only in those patients with lacrimation vs those without it ( p = 0.013). There was no significant correlation between CGRP levels and the score in the CAPS scale. Conclusions Serum VIP, but not CGRP, levels seem to reflect the rate of activation of the parasympathetic arm of the TVS in migraine. [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]

In the present work, the effect of mixing TiO2 with different portions of activated carbon (AC) has been studied. Transmission electron microscopy (TEM), scanning electron micrograph (SEM), laser scattering, FTIR and UV spectrophotometric analysis have shown changes of some of the TiO2 physico-chemical characteristics in catalysts containing an AC concentration lower than 15% in weight. Changes in the catalyst colour, the vibration bands of the hydroxylic groups from FTIR studies and the UV absorption spectrum have been observed. It seems that these changes correspond with TiO2 acid–base changes. SEM and TEM studies show a perfect TiO2 particles distribution on the AC surface in catalysts with lower AC contents, that also yields a homogeneous particle size distribution. One of the most interesting features of the resulting catalysts is their fast decantability in comparison with that of TiO2. This way one of the most important drawbacks of photocatalysis, the catalyst separation from the solution, may be overcome.The present study shows that the AC not only exerts a synergistic effect when is combined with TiO2 as some authors suggest, but it also modifies the catalyst characteristics. [Copyright &y& Elsevier]

It has been demonstrated that the modification of the TiO2 acid–base properties by the presence of activated carbon (AC) considerably modify the interaction of some molecules with the catalyst surface and hence its photocatalytic characteristics.FTIR studies have shown that while phenol interacts with TiO2 yielding a phenoxide, in the catalyst low AC containing catalysts mixtures the surfacial hydroxylic groups are inserted in the aromatic ring in the symmetric position to the –OH group. Additionally, the 4-aminophenol study shows that the molecule interacts with the TiO2 surface by means of the amino group, while in the catalyst containing AC the interaction takes place through the hydroxylic group. These results have confirmed the catalyst acid–base properties changes determined by the characterisation studies already performed. Also, it has been observed that catalysts with the lowest AC content show better catalytic behaviour than the untreated TiO2 and those with higher AC load. Another interesting result is the efficiency of these catalysts under solar irradiation. [Copyright &y& Elsevier]