Multifrequency polarimetric synthetic aperture radar observations of sea ice

The first known fully polarimetric airborne synthetic aperture radar (SAR) data set of sea ice is introduced. The full Stokes matrix information generated from C, L, and P band data characterize the scattering behavior of different ice types. Polarization ratios and phase differences between linear copolarized returns are used for discrimination between particular image features and mechanisms are suggested for the observed polarimetric characteristics. Results indicate that combinations of frequency and polarization enhance current capability to distinguish ice of different properties using single frequency, fixed polarization microwave radar. -from Author

Structure from motion photogrammetry in forestry : a review

AbstractPurpose of ReviewThe adoption of Structure from Motion photogrammetry (SfM) is transforming the acquisition of three-dimensional (3D) remote sensing (RS) data in forestry. SfM photogrammetry enables surveys with little cost and technical expertise. We present the theoretical principles and practical considerations of this technology and show opportunities that SfM photogrammetry offers for forest practitioners and researchers.Recent FindingsOur examples of key research indicate the successful application of SfM photogrammetry in forestry, in an operational context and in research, delivering results that are comparable to LiDAR surveys. Reviewed studies have identified possibilities for the extraction of biophysical forest parameters from airborne and terrestrial SfM point clouds and derived 2D data in area-based approaches (ABA) and individual tree approaches. Additionally, increases in the spatial and spectral resolution of sensors available for SfM photogrammetry enable forest health assessment and monitoring. The presented research reveals that coherent 3D data and spectral information, as provided by the SfM workflow, promote opportunities to derive both structural and physiological attributes at the individual tree crown (ITC) as well as stand levels.SummaryWe highlight the potential of using unmanned aerial vehicles (UAVs) and consumer-grade cameras for terrestrial SfM-based surveys in forestry. Offering several spatial products from a single sensor, the SfM workflow enables foresters to collect their own fit-for-purpose RS data. With the broad availability of non-expert SfM software, we provide important practical considerations for the collection of quality input image data to enable successful photogrammetric surveys

Human umbilical cord mesenchymal stem cell-derived extracellular vesicles ameliorate airway inflammation in a rat model of Chronic Obstructive Pulmonary Disease (COPD)

Background Chronic obstructive pulmonary disease (COPD) is an incurable and debilitating chronic disease characterized by progressive airflow limitation associated with abnormal levels of tissue inflammation. Therefore, stem cell-based approaches to tackle the condition are currently a focus of regenerative therapies for COPD. Extracellular vesicles (EVs) released by all cell types are crucially involved in paracrine, extracellular communication. Recent advances in the field suggest that stem cell-derived EVs possess a therapeutic potential which is comparable to the cells of their origin. Methods In this study, we assessed the potential anti-inflammatory effects of human umbilical cord mesenchymal stem cell (hUC-MSC)-derived EVs in a rat model of COPD. EVs were isolated from hUC-MSCs and characterized by the transmission electron microscope, western blotting, and nanoparticle tracking analysis. As a model of COPD, male Sprague-Dawley rats were exposed to cigarette smoke for up to 12 weeks, followed by transplantation of hUC-MSCs or application of hUC-MSC-derived EVs. Lung tissue was subjected to histological analysis using haematoxylin and eosin staining, Alcian blue-periodic acid-Schiff (AB-PAS) staining, and immunofluorescence staining. Gene expression in the lung tissue was assessed using microarray analysis. Statistical analyses were performed using GraphPad Prism 7 version 7.0 (GraphPad Software, USA). Student’s t test was used to compare between 2 groups. Comparison among more than 2 groups was done using one-way analysis of variance (ANOVA). Data presented as median ± standard deviation (SD). Results Both transplantation of hUC-MSCs and application of EVs resulted in a reduction of peribronchial and perivascular inflammation, alveolar septal thickening associated with mononuclear inflammation, and a decreased number of goblet cells. Moreover, hUC-MSCs and EVs ameliorated the loss of alveolar septa in the emphysematous lung of COPD rats and reduced the levels of NF-κB subunit p65 in the tissue. Subsequent microarray analysis revealed that both hUC-MSCs and EVs significantly regulate multiple pathways known to be associated with COPD. Conclusions In conclusion, we show that hUC-MSC-derived EVs effectively ameliorate by COPD-induced inflammation. Thus, EVs could serve as a new cell-free-based therapy for the treatment of COPD

Parallel Matching of Synthetic Aperture Radar Images

. This paper presents an MPI-parallelized version of a matching algorithm for synthetic aperture radar (SAR) images. First the necessity for automated matching and the chosen algorithm are outlined briey, and the algorithmic structure and the applied parallelization strategy are then presented and discussed. Performance results on a Cray T3D and a PowerChallenge from SGI are given, showing unexpected dierences between these architectures. Performance analysis indicates a bottleneck in data I/O. 1 Introduction Producing an atlas of planet Venus based on data sensed by the Magellan probe is challenging due to the amount of data and the algorithms needed. More than 400 Gbyte of raw data must be processed, partially with specialized SAR algorithms that are very compute-intensive. NASA created the so-called Magellan Stereo Toolkit (MST) [1] as a collection of sequential algorithms which an individual data user could employ to process small subsets of the Magellan images. The mos..

Providing Multimedia Tools for Recording, Reconstruction, Visualisation and Database Storage/Access of Archaeological Excavations

Over the years archaeologists have been swift to embrace new advances in technology that allow them to more comprehensively document the results of their work. Today it is commonplace to find information technologies, in the form MS Office-type tools with some CAD and GIS, deployed for primary data capture, analysis, presentation and publication. While these computing technologies can be used effectively to record and interpret archaeological sites, the radical developments in 3D recording, reconstruction and visualisation tools have had relatively limited impact upon the archaeological community. This is unfortunate as these new technologies have the potential to (a) enable the archaeologists to record their unrepeatable experiments to unprecedented levels of accuracy, (b) enable the archaeologists to reconstruct artefacts such as pottery from sherds, textures and sites from different eras (c) visualise the wealth of excavated information in dynamic new ways away from the archaeological site during post-excavation analysis, (d) make this wealth of detail available to the scholarly community as part of the publication process and secure its digital longevity through its deposition in a trusted digital library/archive and (e) communicate the excitement and importance of their archaeological site and its finds to an interested non-academic audience. This paper describes the overall concept of the EU funded project, 3D Measurement and Virtual Reconstruction of Ancient Lost Worlds of Europe (3D MURALE), that has developed and created a set of low-cost multimedia tools for recording, reconstructing, encoding, and visualising archaeological artefacts and site.The 4th International Symposium on Virtual Reality, Archaeology and Intelligent Cultural Heritag