134 research outputs found

    Accurate Optical Target Pose Determination For Applications In Aerial Photogrammetry

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    We propose a new design for an optical coded target based on concentric circles and a position and orientation determination algorithm optimized for high distances compared to the target size. If two ellipses are fitted on the edge pixels corresponding to the outer and inner circles, quasi-analytical methods are known to obtain the coordinates of the projection of the circles center. We show the limits of these methods for quasi-frontal target orientations and in presence of noise and we propose an iterative refinement algorithm based on a geometric invariant. Next, we introduce a closed form, computationally inexpensive, solution to obtain the target position and orientation given the projected circle center and the parameters of the outer circle projection. The viability of the approach is demonstrated based on aerial pictures taken by an UAV from elevations between 10 to 100 m. We obtain a distance RMS below 0.25 % under 50 m and below 1 % under 100 m with a target size of 90 cm, part of which is a deterministic bias introduced by image exposure

    ON RAW INERTIAL MEASUREMENTS IN DYNAMIC NETWORKS

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    Dynamic Networks have been introduced in the literature to solve multi-sensor fusion problems for navigation and mapping. They have been shown to outperform conventional methods in challenging scenarios, such as corridor mapping or self-calibration. In this work we investigate the problem of how raw inertial readings can be fused with GNSS position observations in Dynamic Networks (DN) with the goal of i) limiting the number of unknowns in the estimation problem and ii) improving the conditioning of the normal equations arising in least-squares adjustments in the absence of spatial constraints (e.g., image observations). For that we propose a modified version of the well known IMU-preintegration method, accounting for a non-constant gravity model, the Earth rotation and the apparent Coriolis force, and we compare it with the conventional DN formulation in a emulated scenario. This consists of a fixed-wing UAV flying four times over a 2 km long corridor

    Assessment of multispectral and hyperspectral imaging systems for digitisation of a Russian icon

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    In a study of multispectral and hyperspectral reflectance imaging, a Round Robin Test assessed the performance of different systems for the spectral digitisation of artworks. A Russian icon, mass-produced in Moscow in 1899, was digitised by ten institutions around Europe. The image quality was assessed by observers, and the reflectance spectra at selected points were reconstructed to characterise the icon’s colourants and to obtain a quantitative estimate of accuracy. The differing spatial resolutions of the systems affected their ability to resolve fine details in the printed pattern. There was a surprisingly wide variation in the quality of imagery, caused by unwanted reflections from both glossy painted and metallic gold areas of the icon’s surface. Specular reflection also degraded the accuracy of the reconstructed reflectance spectrum in some places, indicating the importance of control over the illumination geometry. Some devices that gave excellent results for matte colour charts proved to have poor performance for this demanding test object. There is a need for adoption of standards for digitising cultural heritage objects to achieve greater consistency of system performance and image quality.This article arose out of a Short-Term Scientific Mission (STSM) conducted by Tatiana Vitorino when visiting University College London during a 2-week period in late October 2015. The research was carried out under the auspices of the European COST Action TD1201 Colour and Space in Cultural Heritage (COSCH). The project website is at http://www.cosch.info. Under the COST rules, TV received funding for travel and accommodation expenses, and all coauthors were able to claim travel expenses to attend the subsequent COSCH project meeting. No other funding was received from COSCH for labour or equipment and all work was done on a voluntary pro bono basis.info:eu-repo/semantics/publishedVersio

    Anti-angiogenic and anti-proliferative graphene oxide nanosheets for tumor cell therapy

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    Graphene oxide (GO) is a bidimensional novel material that exhibits high biocompatibility and angiogenic properties, mostly related to the intracellular formation of reactive oxygen species (ROS). In this work, we set up an experimental methodology for the fabrication of GO@peptide hybrids by the immobilization, via irreversible physical adsorption, of the Ac-(GHHPH)4-NH2 peptide sequence, known to mimic the anti-angiogenic domain of the histidine-proline-rich glycoprotein (HPRG). The anti-proliferative capability of the graphene-peptide hybrids were tested in vitro by viability assays on prostate cancer cells (PC-3 line), human neuroblastoma (SH-SY5Y), and human retinal endothelial cells (primary HREC). The anti-angiogenic response of the two cellular models of angiogenesis, namely endothelial and prostate cancer cells, was scrutinized by prostaglandin E2 (PGE2) release and wound scratch assays, to correlate the activation of inflammatory response upon the cell treatments with the GO@peptide nanocomposites to the cell migration processes. Results showed that the GO@peptide nanoassemblies not only effectively induced toxicity in the prostate cancer cells, but also strongly blocked the cell migration and inhibited the prostaglandin-mediated inflammatory process both in PC-3 and in HRECs. Moreover, the cytotoxic mechanism and the internalization efficiency of the theranostic nanoplatforms, investigated by mitochondrial ROS production analyses and confocal microscopy imaging, unraveled a dose-dependent manifold mechanism of action performed by the hybrid nanoassemblies against the PC-3 cells, with the detection of the GO-characteristic cell wrapping and mitochondrial perturbation. The obtained results pointed out to the very promising potential of the synthetized graphene-based hybrids for cancer therapy

    A tunable nanoplatform of nanogold functionalised with Angiogenin peptides for anti-angiogenic therapy of brain tumours

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    Angiogenin (ANG), an endogenous protein that plays a key role in cell growth and survival, has been scrutinised here as promising nanomedicine tool for the modulation of pro-/anti-angiogenic processes in brain cancer therapy. Specifically, peptide fragments from the putative cell membrane binding domain (residues 60-68) of the protein were used in this study to obtain peptide-functionalised spherical gold nanoparticles (AuNPs) of about 10 nm and 30 nm in optical and hydrodynamic size, respectively. Different hybrid biointerfaces were fabricated by peptide physical adsorption (Ang60-68) or chemisorption (the cysteine analogous Ang60-68Cys) at the metal nanoparticle surface, and cellular assays were performed in the comparison with ANG-functionalised AuNPs. Cellular treatments were performed both in basal and in copper-supplemented cell culture medium, to scrutinise the synergic effect of the metal, which is another known angiogenic factor. Two brain cell lines were investigated in parallel, namely tumour glioblastoma (A172) and neuron-like differentiated neuroblastoma (d-SH-SY5Y). Results on cell viability/proliferation, cytoskeleton actin, angiogenin translocation and vascular endothelial growth factor (VEGF) release pointed to the promising potentialities of the developed systems as anti-angiogenic tunable nanoplaftforms in cancer cells treatment

    Capacitación de ayudantes alumnos para la acción tutorial entre pares

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    El concepto de tutoría fue adaptándose a diversos marcos académicos y sociales desde la época medieval hasta nuestros días. Posiblemente el modelo más completo es el de tutoría integral, que como queda explicitado en su nombre atiende globalmente las distintas dimensiones del estudiante, facilitando el desarrollo intelectual, afectivo y profesional. La acción tutorial cumple con la formación de futuros actores sociales capaces de producir los cambios necesarios, acorde al tiempo y lugar.Facultad de Ciencias Médica

    Copy number variations residing outside the SHOX enhancer region are involved in Short Stature and Léri-Weill dyschondrosteosis

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    Background: SHOX enhancer CNVs, affecting one or more of the seven recognized evolutionary conserved non-coding elements (CNEs) represent one of the most frequent cause of SHOX-haploinsufficiency. During the diagnostic workflow deletions/duplications have been identified downstream SHOX not including any of the these CNEs. Methods: Fine tiling aCGH and breakpoint PCR were used to characterize the critical interval and to search for novel alterations in a cohort of selected patients. Results: Screening of 252 controls provided evidence that duplications in this area represent likely benign variants whereas none of the deletions were detected. These findings suggested that other alterations relevant for SHOX-haploinsufficiency might be missed by the standard diagnostic methods. To identify such undisclosed elements, the aCGH was used to reanalyze 52 unresolved cases with clinical features strongly suggestive of SHOX-haploinsufficiency. This analysis followed by the screening of 210 patients detected two partially overlapping small deletions of ~12 and ~8 kb in four unrelated individuals, approximately 15 kb downstream SHOX, that were absent in 720 normal stature individuals. Conclusion: Our results strengthen the hypothesis that alterations of yet unidentified cis-regulatory elements residing outside those investigated through conventional methods, might explain the phenotype in ISS/LWD patients thus enlarging the spectrum of variants contributing to SHOX-haploinsufficiency

    Detection of antibodies to human herpesvirus 8 in Italian children: evidence for horizontal transmission

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    Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma associated herpesvirus (KSHV), has been shown to be the causative agent for Kaposi's sarcoma (KS) and to be more prevalent in populations or risk groups at increased risk for KS. HHV-8 infection is rare in children from the US and the UK, but has been reported in African children. In this study we examine HHV-8 infection in children from Italy, a country with an elevated prevalence of HHV-8 in adults and high socio-economic conditions. © 2000 Cancer Research Campaig

    Long-term expression of the Paganica Fault vs. 2009 L’Aquila Earthquake surface ruptures: looking for a better understanding of its seismic behavior

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    The Mw6.3, April 6, 2009 earthquake occurred on the previously identified Paganica normal fault and produced a 3 km-long co-seismic surface rupture along its northern section, with few centimeters of vertical displacement. Extensive 1:10,000-scale geological and geomorphological mapping has been carried out, focusing on the characterization of the long-term expression of the Paganica Fault at the surface. The field mapping was integrated by observations, made on 1:33,000 scale aerial photographs (GAI), 5-m-resolution Digital Elevation Model and standard morphometric derivatives (hill-shaded and slope angle maps, Spatial Analystâ„¢). Particular attention was devoted to the study of the continental deposits and landforms affected by cumulative offset with the aim to reconstruct the Quaternary deformational history of the fault. The fault runs for a total length of 20 km and, along with antithetic faults on its hanging-wall, forms the graben of the Middle Aterno River Valley. The whole fault system and the variable setting of deformation affecting the continental deposits at the surface were identified. The Paganica long-term morphologic signature is represented by a set of prominent scarps formed by the tectonic juxtaposition of late Pliocene-middle Pleistocene and late Pleistocene alluvial deposits, and by lower scarps in late Pleistocene-Holocene deposits. In addition, evident Quaternary erosional and depositional paleosurfaces were recognized and sampled for 14C and OSL (Optically Stimulated Luminescence) and tephra chronology dating for long-term slip-rate calculations. This study resulted helpful to locate four paleoseismological investigations (see Pantosti et al. talk) and to provide the appropriate context for correctly interpret the depositional bodies outcropping on the trench walls. These paleoseismological investigations evidenced the presence of repeated late Pleistocene-Holocene activity and allowed for slip-rate estimation at a shorter time-scale. Such estimates were valuable for a comparison with the preliminary estimates on late Pleistocene calculations carried out by geomorphological investigations. Moreover, we correlated co-seismic deformations with the long-term morphologies and structures. The 2009 co-seismic ruptures show a general coherence with the long-term Paganica fault trace, both in terms of location and style. However, the limited extent of the 2009 surface ruptures coincides with the portion of the fault trace where deformation is more localized and few splays contribute to the extension. This is also testified by the presence on its hanging-wall of a large late Pleistocene-Holocene alluvial fan that subsides over the basin depocenter. Conversely, where the Paganica fault system branches out, various splays accommodated the small 2009 co-seismic throw, resulting in a distributed and not evident extensional strain. The preserved fault-related geomorphology is evidence for the persistence of the rupture complexities during Quaternary. On this light, further studies on the style of fault activity are needed to estimate if the Paganica fault is capable of earthquakes with Magnitude larger than the 2009 event.SubmittedVienna, Austriaope
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