17 research outputs found

    A review of the use of terrestrial laser scanning application for change detection and deformation monitoring of structures

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    Change detection and deformation monitoring is an active area of research within the field of engineering surveying as well as overlapping areas such as structural and civil engineering. The application of Terrestrial Laser Scanning (TLS) techniques for change detection and deformation monitoring of concrete structures has increased over the years as illustrated in the past studies. This paper presents a review of literature on TLS application in the monitoring of structures and discusses registration and georeferencing of TLS point cloud data as a critical issue in the process chain of accurate deformation analysis. Past TLS research work has shown some trends in addressing issues such as accurate registration and georeferencing of the scans and the need of a stable reference frame, TLS error modelling and reduction, point cloud processing techniques for deformation analysis, scanner calibration issues and assessing the potential of TLS in detecting sub-centimetre and millimetre deformations. However, several issues are still open to investigation as far as TLS is concerned in change detection and deformation monitoring studies such as rigorous and efficient workflow methodology of point cloud processing for change detection and deformation analysis, incorporation of measurement geometry in deformation measurements of high-rise structures, design of data acquisition and quality assessment for precise measurements and modelling the environmental effects on the performance of laser scanning. Even though some studies have attempted to address these issues, some gaps exist as information is still limited. Some methods reviewed in the case studies have been applied in landslide monitoring and they seem promising to be applied in engineering surveying to monitor structures. Hence the proposal of a three-stage process model for deformation analysis is presented. Furthermore, with technological advancements new TLS instruments with better accuracy are being developed necessitating more research for precise measurements in the monitoring of structures

    Dasatinib impairs long-term expansion of leukemic progenitors in a subset of acute myeloid leukemia cases

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    A number of signaling pathways might be frequently disrupted in acute myeloid leukemia (AML). We questioned whether the dual SRC/ABL kinase inhibitor dasatinib can affect AML cells and whether differences can be observed with normal CD34+ cells. First, we demonstrated that normal cord blood (CB) CD34+ cells were unaffected by dasatinib at a low concentration (0.5 nM) in the long-term culture on MS5 stromal cells. No changes were observed in proliferation, differentiation, and colony formation. In a subset of AML cases (3/15), a distinct reduction in cell proliferation was observed, ranging from 48% to 91% inhibition at 0.5 nM of dasatinib, in particular, those characterized by BCR–ABL or KIT mutations. Moreover, the inhibitory effects of dasatinib were cytokine specific. Stem cell factor-mediated proliferation was significantly impaired, associated with a reduced phosphorylation of ERK1/2 and STAT5, whereas no effect was observed on interleukin-3 and thrombopoietin-mediated signaling despite SRC activation. In conclusion, this study demonstrates that dasatinib is a potential inhibitor in a subgroup of AML, especially those that express BCR–ABL or KIT mutations

    Establishing human leukemia xenograft mouse models by implanting human bone marrow-like scaffold-based niches

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    To begin to understand the mechanisms that regulate self-renewal, differentiation, and transformation of human hematopoietic stem cells or to evaluate the efficacy of novel treatment modalities, stem cells need to be studied in their own species-specific microenvironment. By implanting ceramic scaffolds coated with human mesenchymal stromal cells into immune-deficient mice, we were able to mimic the human bone marrow niche. Thus, we have established a human leukemia xenograft mouse model in which a large cohort of patient samples successfully engrafted, which covered all of the important genetic and risk subgroups. We found that by providing a humanized environment, stem cell self-renewal properties were better maintained as determined by serial transplantation assays and genome-wide transcriptome studies, and less clonal drift was observed as determined by exome sequencing. The human leukemia xenograft mouse models that we have established here will serve as an excellent resource for future studies aimed at exploring novel therapeutic approaches

    Improving maritime situational awareness by fusing sensor information and intelligence

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    In present-day military security operations threats are more difficult to reveal than in conventional warfare theatres, since they take place during the course of normal life. These maritime missions often take place in littoral environments, where acts of piracy, drug trafficking and other threatening events become obscured in the crowd of everyday fisheries, cargo traders, ferries and pleasure cruises, hindering situation awareness. We aim to improve situation awareness and threat detection capabilities in maritime scenarios by combining sensor-based information with context information and intelligence from various sources. The fusion and analysis in order to reveal suspect from normal behavior is based on domain ontologies. A test bed allows the study of various exploitation and assessments techniques applied to these domain ontologies. Using an appropriate scenario we have simulated suspect and normal behaviour to test the applicability of the various techniques. © 2011 IEEE

    Roberts syndrome is caused by mutations in ESCO2, a human homolog of yeast ECO1 that is essential for the establishment of sister chromatid cohesion

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    Roberts syndrome is an autosomal recessive disorder characterized by craniofacial anomalies, tetraphocomelia and loss of cohesion at heterochromatic regions of centromeres and the Y chromosome. We identified mutations in a new human gene, ESCO2, associated with Roberts syndrome in 15 kindreds. The ESCO2 protein product is a member of a conserved protein family that is required for the establishment of sister chromatid cohesion during S phase and has putative acetyltransferase activity
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