bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying horizontal and vertical tracer mass fluxes of a daytime valley boundary layer
Authors: Leukauf Daniel , Gohm Alexander , Rotach Mathias W.
Published: June 2016

Abstract. The transport and mixing of pollution during the daytime evolution of a valley boundary layer is studied in an idealized way. The goal is to quantify horizontal and vertical tracer mass fluxes between four different valley volumes: the mixed layer at the valley floor, the slope wind layer, the stable core and the free atmosphere above the valley. For this purpose, large eddy simulations are conducted with the Weather Research and Forecasting (WRF) model for a quasi-two-dimensional valley. The valley geometry consists of two slopes with constant slope angle, which rise to a crest height of 1500 m, and a 4 km wide flat valley floor in between. The valley is 20 km long and homogeneous in along-valley direction. Hence, only slope winds but no valley winds can evolve above this terrain. Various experiments are conducted for different surface heating and static stabilities. The surface sensible heat flux is horizontally homogeneous and prescribed by a sine function with amplitudes of Ashf = 62.5, 125, 250 and 375 W m−2 respectively. The initial sounding is characterized by an atmosphere at rest and by a constant Brunt-Väisälä frequency which is varied between N = 0.006 and 0.02 s−1. A passive tracer is released with an arbitrary but constant rate at the valley floor and resulting tracer fluxes are evaluated between the aforementioned volumes. As a result of the surface heating, a mixed layer establishes in the lower part of the valley with a stable layer on top – the so-called stable core. The wind speed and, hence, the mass flux within the slope wind layer decreases with height due to the vertically increasing stability of the environment near the center of the valley. Due to mass continuity, this leads to a partial redirection of the flow from the slope wind layer towards the valley center and the formation of a horizontal intrusion above the mixed layer. This intrusion is associated with a transport of tracer mass from the slope wind layer towards the valley center. For Ashf = 250 W m−2 and N = 0.018 s−1, about 45 % of the tracer mass released at the valley floor is transported by this circulation to the stable core. This number rapidly decreases with decreasing stability and increasing forcing since the breakup of the stable layer and, hence, the complete neutralization of the stratification in the valley is reached earlier. Between 60 and 85 % of the total tracer mass enters the slope wind layer at its lower end, but only a fraction is exported at crest height for high stabilities and a weak forcing. The total export of tracer mass drops from 80 % for the weakest stability and the strongest forcing to about 5 % for the strongest stability and the weakest forcing. The effects of initial stability and forcing can be combined to a single parameter, the breakup parameter B. An analytical function is presented that describes the exponential decrease of the percentage of exported tracer mass with increasing B.
On-line single particle analysis of ice particle residuals from mountain-top mixed-phase clouds using laboratory derived particle type assignment
Authors: Schmidt S. , Schneider J. , Klimach T. , Mertes S. , Schenk L. P. , Curtius J. , Borrmann S.
Published: June 2016

Abstract. In-situ single particle analysis of ice particle residuals (IPR) and out-of-cloud aerosol particles was conducted by means of laser ablation mass spectrometry during the intensive INUIT-JFJ/CLACE campaign at the high alpine research station Jungfraujoch (3580 m a.s.l.) in January/February 2013. During the four week campaign more than 70000 out-of-cloud aerosol particles and 595 IPR were analyzed covering a particle size diameter range from 100 nm to 3 µm. The IPR were sampled during 273 hours while the station was covered by mixed-phase clouds at ambient temperatures between −27 °C and −6 °C. The identification of particle types is based on laboratory studies of different types of biological, mineral and anthropogenic aerosol particles. As outcome instrument specific marker peaks for the different investigated particle types were obtained and applied to the field data. The results show that the sampled IPR contain a larger relative amount of natural, primary aerosol, like soil dust (13 %) and minerals (11 %), in comparison to out-of-cloud aerosol particles (2 % and < 1 %, respectively). Additionally, anthropogenic aerosol particles, like particles from industrial emissions and lead-containing particles, were found to be more abundant in the IPR than in the out-of-cloud aerosol. The out-of-cloud aerosol contained a large fraction of aged particles (30 %, including organic material and secondary inorganics), whereas this particle type was much less abundant (3 %) in the IPR. In a selected subset of the data where a direct comparison between out-of-cloud aerosol particles and IPR in air masses with similar origin was possible, a pronounced enhancement of biological particles was found in the IPR.
The status and challenge of global fire modelling
Authors: Hantson Stijn , Arneth Almut , Harrison Sandy P. , Kelley Douglas I. , Prentice I. Colin , Rabin Sam S. , Archibald Sally , Mouillot Florent , Arnold Steve R. , Artaxo Paulo , Bachelet Dominique , Ciais Philippe , Forrest Matthew , Friedlingstein Pierre , Hickler Thomas , Kaplan Jed O. , Kloster Silvia , Knorr Wolfgang , Lasslop Gitta , Li Fang , Mangeon Stephane , Melton Joe R. , Meyn Andrea , Sitch Stephen , Spessa Allan , van der Werf Guido R. , Voulgarakis Apostolos , Yue Chao
Published: June 2016

Abstract. Biomass burning impacts vegetation dynamics, biogeochemical cycling, atmospheric chemistry, and climate, with sometimes deleterious socio-economic impacts. Under future climate projections it is often expected that the risk of wildfires will increase. Our ability to predict the magnitude and geographic pattern of future fire impacts rests on our ability to model fire regimes, using either well-founded empirical relationships or process-based models with good predictive skill. While a large variety of models exist today, it is still unclear which type of model or degree of complexity is required to model fire adequately at regional to global scales. This is the central question underpinning the creation of the Fire Model Intercomparison Project (FireMIP), an international initiative to compare and evaluate existing global fire models against benchmark data sets for present-day and historical conditions. In this paper we review how fires have been represented in fire-enabled dynamic global vegetation models (DGVMs) and give an overview of the current state of the art in fire-regime modelling. We indicate which challenges still remain in global fire modelling and stress the need for a comprehensive model evaluation and outline what lessons may be learned from FireMIP.
Climate impacts on multidecadal pCO2 variability in the North Atlantic: 1948–2009
Authors: Breeden Melissa L. , McKinley Galen A.
Published: June 2016

Abstract. The North Atlantic is the most intense region of ocean CO2 uptake in term of units per area. Here, we investigate multidecadal timescale variability of the partial pressure of CO2 (pCO2) that is due to the natural carbon cycle, using a regional model forced with realistic climate and preindustrial atmospheric pCO2 for 1948–2009. Large-scale patterns of natural pCO2 variability are primarily associated with basin-averaged sea surface temperature (SST) that, in turn, is composed of two parts: the Atlantic Multidecadal Oscillation (AMO) and a long-term positive SST trend. The North Atlantic Oscillation (NAO) drives a secondary mode of variability. For the primary mode, positive AMO and the SST trend modify pCO2 with different mechanisms and spatial patterns. Positive AMO is also associated with a significant reduction in dissolved inorganic carbon (DIC) in the subpolar gyre, due primarily to reduced vertical mixing; the net impact of positive AMO is to reduce pCO2 in the subpolar gyre. Through direct impacts on SST, the net effect of positive AMO is to increase pCO2 in the subtropical gyre. From 1980 to present, long-term SST warming has amplified AMO impacts on pCO2.
Stable carbon isotope deviations in benthic foraminifera as proxy for organic carbon fluxes in the Mediterranean Sea
Authors: Theodor Marc , Schmiedl Gerhard , Jorissen Frans , Mackensen Andreas
Published: June 2016

Abstract. We have determined stable carbon isotope ratios of epifaunal and shallow infaunal benthic foraminifera to relate the inferred gradient of pore water δ13CDIC to varying trophic conditions, and to test the potential of developing a transfer function for organic matter flux rates. The data set is based on samples retrieved from a well-defined bathymetric range (400–1500 m water depth) of sub-basins in the western, central and eastern Mediterranean Sea. Regional contrasts in organic matter fluxes and associated δ13CDIC of pore water are recorded by the δ13C difference (Δδ13CUmed-Epi) between the shallow infaunal Uvigerina mediterranea and epifaunal species (Planulina ariminensis, Cibicidoides pachydermus, Cibicides lobatulus). The Δδ13CUmed-Epi values range from −0.46 to −2.13 ‰, with generally higher offsets at more eutrophic sites. Because of ontogenetic shifts in the δ13C signal of U. mediterranea of up to 1.04 ‰, only tests larger than 600 µm were used for the quantitative environmental evaluation. The measured δ13C deviations are related to site-specific differences in microhabitat, depth of the principal redox boundary, and TOC content. The Δδ13CUmed-Epi values reveal a consistent relation to Corg fluxes estimated from satellite-derived surface water primary production in open-marine settings of the Alboran Sea, Mallorca Channel, Strait of Sicily and southern Aegean Sea. In contrast, Δδ13CUmed-Epi values in areas affected by intense resuspension and riverine organic matter sources of the northern to central Aegean Sea and the canyon systems of the Gulf of Lions suggest higher Corg fluxes compared to the values based on recent surface primary production. Considering the regional biases and uncertainties, a first Δδ13CUmed-Epi based transfer function for Corg fluxes could be established for the Mediterranean Sea.
Armor breakup and reformation in a degradational laboratory experiment
Authors: Orrú Clara , Blom Astrid , Uijttewaal Wim S. J.
Published: June 2016

Abstract. Armor breakup and reformation was studied in a laboratory experiment using a trimodal mixture composed of a 1 mm sand fraction and two gravel fractions (6 and 10 mm). The initial bed was characterized by a stepwise downstream fining pattern (trimodal reach) and a downstream sand reach, and the experiment was conducted under conditions without sediment supply. In the initial stage of the experiment an armor formed over the trimodal reach. The formation of the armor under partial transport conditions led to an abrupt spatial transition in the bed slope and in the mean grain size of the bed surface, as such showing similar results to a previous laboratory experiment conducted with a bimodal mixture. The focus of the current analysis is to study the mechanisms of armor breakup. After an increase in flow rate the armor broke up and a new coarser armor quickly formed. The breakup initially induced a bed surface fining due to the exposure of the finer substrate, which was accompanied by a sudden increase in the sediment transport rate, followed by the formation of an armor that was coarser than the initial one. The reformation of the armor was enabled by the supply of coarse material from the upstream degrading reach and the presence of gravel in the original substrate sediment. Here armor breakup and reformation enabled slope adjustment such that the new steady state was closer to normal flow conditions.
A new Late Jurassic halecomorph fish from the marine Vaca Muerta Formation, Argentina, southwestern Gondwana
Authors: Gouiric-Cavalli Soledad
Published: June 2016

Abstract. The knowledge of Mesozoic fish faunas of the Southern Hemisphere is still inadequate; the diversity and evolution of the Late Jurassic marine ichthyofaunas of Argentina remain unclear. One fish recovered from the Tithonian levels of the Los Catutos Member of the Vaca Muerta Formation, southwestern Argentina was considered a "caturid-like" halecomorph for almost 30 years. Recently, it was proposed that it could belong to the Pachycormiformes. A thorough comparative anatomical study of the material is conducted to test whether it could be included in †Caturidae or †Pachycormidae. The specimen is assigned to †Caturidae as a new genus and species: †Catutoichthys olsacheri (http://zoobank.org/urn:lsid:zoobank.org:act:6884876C-075C-433B-90B7-74187FC04C26, registered on 1 June 2016). The new taxon is based on a unique character combination, three of which are exclusive to †Catutoichthys olsacheri among caturids–diplospondylous vertebral column with triangular basidorsals and well-developed and fan-shaped basiventrals; neural and haemal spines strongly inclined to the body axis at an angle of 14°; a large number of infrahaemals; rounded amioid-type scales with an unornamented free field. The new taxon provides anatomical information useful for further understanding the anatomy and evolution of caturid fishes.
Data flow of spectral UV measurements at Sodankylä and Jokioinen
Authors: Mäkelä Jakke Sakari , Lakkala Kaisa , Koskela Tapani , Karppinen Tomi , Karhu Juha Matti , Savastiouk Vladimir , Suokanerva Hanne , Kaurola Jussi , Arola Antti , Lindfors Anders Vilhelm , Meinander Outi , de Leeuw Gerrit , Heikkilä Anu
Published: June 2016

Abstract. The data flow involved in a long-term continuous solar spectral UV irradiance monitoring program is investigated and structured to provide an overall view on the multiphase process from data acquisition to the final products. The program employing Brewer spectrophotometers as measuring instruments is maintained by the Finnish Meteorological Institute (FMI) ever since the 1990s at two sites in Finland: Sodankylä (67° N) and Jokioinen (61° N). It is built upon rigorous operation routines, processing procedures, and tools for quality control (QC) and quality analysis (QA) under continuous development and evaluation. Three distinct levels of data emerge, each after certain phase in the data flow: Level 0 denoting raw data, Level 1 meaning calibrated data processed in near-real time, and Level 2 comprising of postprocessed data corrected for all distinguishable errors and known inaccuracies. The final products disseminated to the users are demonstrated to result from a process with a multitude of separate steps, each required in the production of high-quality data on solar UV radiation at the Earth's surface.
ASSESSING URBAN DROUGHTS IN A SMART CITY FRAMEWORK
Authors: Obringer R. , Zhang X. , Mallick K. , Alemohammad S. H. , Niyogi D.
Published: June 2016

Abstract. This study aims to integrate environmental data for drought monitoring to reduce uncertainty in urban drought characterization as part of the smart city framework. Currently, drought monitoring in urban areas is a challenge. This is due, in part, to a lack of knowledge on the subject of urban droughts and urban drought vulnerability. A critical part to assessing urban drought and implementing the necessary policies is determining drought conditions. Often the timing and severity of the drought can leave cities to enforce water restrictions, so accuracy of this determination has socioeconomic implications. To determine drought conditions, we need to know the water balance over the urban landscape, of which evapotranspiration (ET) is a key variable. However, ET data and models have high uncertainty when compared to other hydrological variables (i.e., precipitation). This is largely due to ill-defined empirical models for characterizing the urban surface resistance parameter (rs) that is used in ET calculations. We propose a method to estimate rs values using a combination of the Surface Temperature Initiated Closure (STIC) method that calculates regional evapotranspiration data and an inverted version of the Penman-Monteith equation. We use this approach across the region surrounding Indianapolis, IN (USA) from 2010-2014. We discuss the potential for this method to be integrated in to smart city framework to improve urban drought assessment.
AN OPTIMISED SYSTEM FOR GENERATING MULTI-RESOLUTION DTMS USING NASA MRO DATASETS
Authors: Tao Y. , Muller J.-P. , Sidiropoulos P. , Veitch-Michaelis J. , Yershov V.
Published: June 2016

Abstract. Within the EU FP-7 iMars project, a fully automated multi-resolution DTM processing chain, called Co-registration ASP-Gotcha Optimised (CASP-GO) has been developed, based on the open source NASA Ames Stereo Pipeline (ASP). CASP-GO includes tiepoint based multi-resolution image co-registration and an adaptive least squares correlation-based sub-pixel refinement method called Gotcha. The implemented system guarantees global geo-referencing compliance with respect to HRSC (and thence to MOLA), provides refined stereo matching completeness and accuracy based on the ASP normalised cross-correlation. We summarise issues discovered from experimenting with the use of the open-source ASP DTM processing chain and introduce our new working solutions. These issues include global co-registration accuracy, de-noising, dealing with failure in matching, matching confidence estimation, outlier definition and rejection scheme, various DTM artefacts, uncertainty estimation, and quality-efficiency trade-offs.
Automatic 3D Extraction of Buildings, Vegetation and Roads from LIDAR Data
Authors: Bellakaout A. , Cherkaoui M. , Ettarid M. , Touzani A.
Published: June 2016

Abstract. Aerial topographic surveys using Light Detection and Ranging (LiDAR) technology collect dense and accurate information from the surface or terrain; it is becoming one of the important tools in the geosciences for studying objects and earth surface. Classification of Lidar data for extracting ground, vegetation, and buildings is a very important step needed in numerous applications such as 3D city modelling, extraction of different derived data for geographical information systems (GIS), mapping, navigation, etc... Regardless of what the scan data will be used for, an automatic process is greatly required to handle the large amount of data collected because the manual process is time consuming and very expensive. This paper is presenting an approach for automatic classification of aerial Lidar data into five groups of items: buildings, trees, roads, linear object and soil using single return Lidar and processing the point cloud without generating DEM. Topological relationship and height variation analysis is adopted to segment, preliminary, the entire point cloud preliminarily into upper and lower contours, uniform and non-uniform surface, non-uniform surfaces, linear objects, and others. This primary classification is used on the one hand to know the upper and lower part of each building in an urban scene, needed to model buildings façades; and on the other hand to extract point cloud of uniform surfaces which contain roofs, roads and ground used in the second phase of classification. A second algorithm is developed to segment the uniform surface into buildings roofs, roads and ground, the second phase of classification based on the topological relationship and height variation analysis, The proposed approach has been tested using two areas : the first is a housing complex and the second is a primary school. The proposed approach led to successful classification results of buildings, vegetation and road classes.
BUILDING FACADE DOCUMENTATION USING LASER SCANNING AND PHOTOGRAMMETRY AND DATA IMPLEMENTATION INTO BIM
Authors: Faltýnová M. , Matoušková E. , Šedina J. , Pavelka K.
Published: June 2016

Abstract. A project started last year called MORE-CONNECT, which focuses on the renovation of buildings (especially building facades) using prefabricated elements. The aim of this project is to create a competitive solution consisting of a technology and processes which enable fast, cost-effective renovation with minimal difficulties to inhabitants. Significant cost savings in renovation costs lies in the usage of prefabricated elements and the reduction of construction works on site. The precision of the prefabricated element depends on the precision of the construction, project and building documentation. This article offers an overview of the possible methods for building documentation and spatial data transfer into BIM (Building Information Modelling) software. The description of methods focuses on laser scanning and photogrammetry (including RPAS based), its advantages, disadvantages and limitations according to the documented building, level of renovation, situation on site etc. The next part involves spatial data transfer into BIM software. A proposed solution is tested in a case study.
A FAST AND FLEXIBLE METHOD FOR META-MAP BUILDING FOR ICP BASED SLAM
Authors: Kurian A. , Morin K. W.
Published: June 2016

Abstract. Recent developments in LiDAR sensors make mobile mapping fast and cost effective. These sensors generate a large amount of data which in turn improves the coverage and details of the map. Due to the limited range of the sensor, one has to collect a series of scans to build the entire map of the environment. If we have good GNSS coverage, building a map is a well addressed problem. But in an indoor environment, we have limited GNSS reception and an inertial solution, if available, can quickly diverge. In such situations, simultaneous localization and mapping (SLAM) is used to generate a navigation solution and map concurrently. SLAM using point clouds possesses a number of computational challenges even with modern hardware due to the shear amount of data. In this paper, we propose two strategies for minimizing the cost of computation and storage when a 3D point cloud is used for navigation and real-time map building. We have used the 3D point cloud generated by Leica Geosystems's Pegasus Backpack which is equipped with Velodyne VLP-16 LiDARs scanners. To improve the speed of the conventional iterative closest point (ICP) algorithm, we propose a point cloud sub-sampling strategy which does not throw away any key features and yet significantly reduces the number of points that needs to be processed and stored. In order to speed up the correspondence finding step, a dual kd-tree and circular buffer architecture is proposed. We have shown that the proposed method can run in real time and has excellent navigation accuracy characteristics.
TOWARDS OBJECT DRIVEN FLOOR PLAN EXTRACTION FROM LASER POINT CLOUD
Authors: Babacan K. , Jung J. , Wichmann A. , Jahromi B. A. , Shahbazi M. , Sohn G. , Kada M.
Published: June 2016

Abstract. During the last years, the demand for indoor models has increased for various purposes. As a provisional step to proceed towards higher dimensional indoor models, powerful and flexible floor plans can be utilised. Therefore, several methods have been proposed that provide automatically generated floor plans from laser point clouds. The prevailing methodology seeks to attain semantic enhancement of a model (e.g. the identification and labelling of its components) built upon already reconstructed (a priori) geometry. In contrast, this paper demonstrates preliminary research on the possibility to directly incorporate semantic knowledge, which is itself derived from the raw data during the extraction, into the geometric modelling process. In this regard, we propose a new method to automatically extract floor plans from raw point clouds. It is based on a hierarchical space partitioning of the data, integrated with primitive selection actuated by object detection. First, planar primitives corresponding to vertical architectural structures are extracted using M-estimator SAmple and Consensus (MSAC). The set of the resulting line segments are refined by a selection process through a novel door detection algorithm, considering optimization of prior information and fitness to the data. The selected lines are used as hyperlines to partition the space into enclosed areas. Finally, a floor plan is extracted from these partitions by Minimum Description Length (MDL) hypothesis ranking. The algorithm is applied on a real mobile laser scanner dataset and the results are evaluated both in terms of door detection and consecutive floor plan extraction.
INTEGRATION OF GEODATA IN DOCUMENTING CASTLE RUINS
Authors: Delis P. , Wojtkowska M. , Nerc P. , Ewiak I. , Lada A.
Published: June 2016

Abstract. Textured three dimensional models are currently the one of the standard methods of representing the results of photogrammetric works. A realistic 3D model combines the geometrical relations between the structure’s elements with realistic textures of each of its elements. Data used to create 3D models of structures can be derived from many different sources. The most commonly used tool for documentation purposes, is a digital camera and nowadays terrestrial laser scanning (TLS). Integration of data acquired from different sources allows modelling and visualization of 3D models historical structures. Additional aspect of data integration is possibility of complementing of missing points for example in point clouds. The paper shows the possibility of integrating data from terrestrial laser scanning with digital imagery and an analysis of the accuracy of the presented methods. The paper describes results obtained from raw data consisting of a point cloud measured using terrestrial laser scanning acquired from a Leica ScanStation2 and digital imagery taken using a Kodak DCS Pro 14N camera. The studied structure is the ruins of the Ilza castle in Poland.
VECTORIZATION OF ROAD DATA EXTRACTED FROM AERIAL AND UAV IMAGERY
Authors: Bulatov Dimitri , Häufel Gisela , Pohl Melanie
Published: June 2016

Abstract. Road databases are essential instances of urban infrastructure. Therefore, automatic road detection from sensor data has been an important research activity during many decades. Given aerial images in a sufficient resolution, dense 3D reconstruction can be performed. Starting at a classification result of road pixels from combined elevation and optical data, we present in this paper a fivestep procedure for creating vectorized road networks. These main steps of the algorithm are: preprocessing, thinning, polygonization, filtering, and generalization. In particular, for the generalization step, which represents the principal area of innovation, two strategies are presented. The first strategy corresponds to a modification of the Douglas-Peucker-algorithm in order to reduce the number of vertices while the second strategy allows a smoother representation of street windings by Bezir curves, which results in reduction – to a decimal power – of the total curvature defined for the dataset. We tested our approach on three datasets with different complexity. The quantitative assessment of the results was performed by means of shapefiles from OpenStreetMap data. For a threshold of 6 m, completeness and correctness values of up to 85% were achieved.
SEMI-AUTOMATIC BUILDING MODELS AND FAÇADE TEXTURE MAPPING FROM MOBILE PHONE IMAGES
Authors: Jeong J. , Kim T.
Published: June 2016

Abstract. Research on 3D urban modelling has been actively carried out for a long time. Recently the need of 3D urban modelling research is increased rapidly due to improved geo-web services and popularized smart devices. Nowadays 3D urban models provided by, for example, Google Earth use aerial photos for 3D urban modelling but there are some limitations: immediate update for the change of building models is difficult, many buildings are without 3D model and texture, and large resources for maintaining and updating are inevitable. To resolve the limitations mentioned above, we propose a method for semi-automatic building modelling and façade texture mapping from mobile phone images and analyze the result of modelling with actual measurements. Our method consists of camera geometry estimation step, image matching step, and façade mapping step. Models generated from this method were compared with actual measurement value of real buildings. Ratios of edge length of models and measurements were compared. Result showed 5.8% average error of length ratio. Through this method, we could generate a simple building model with fine façade textures without expensive dedicated tools and dataset.
The New Approach to Camera Calibration – GCPs or TLS Data?
Authors: Markiewicz J. , Podlasiak P. , Kowalczyk M. , Zawieska D.
Published: June 2016

Abstract. Camera calibration is one of the basic photogrammetric tasks responsible for the quality of processed products. The majority of calibration is performed with a specially designed test field or during the self-calibration process. The research presented in this paper aims to answer the question of whether it is necessary to use control points designed in the standard way for determination of camera interior orientation parameters. Data from close-range laser scanning can be used as an alternative. The experiments shown in this work demonstrate the potential of laser measurements, since the number of points that may be involved in the calculation is much larger than that of commonly used ground control points. The problem which still exists is the correct and automatic identification of object details in the image, taken with a tested camera, as well as in the data set registered with the laser scanner.
Joint interpretation of magnetotelluric, seismic, and well-log data in Hontomín (Spain)
Authors: Ogaya Xènia , Alcalde Juan , Marzán Ignacio , Ledo Juanjo , Queralt Pilar , Marcuello Alex , Martí David , Saura Eduard , Carbonell Ramon , Benjumea Beatriz
Published: June 2016

Abstract. Hontomín (N of Spain) hosts the first Spanish CO2 storage pilot plant. The subsurface characterization of the site included the acquisition of a 3-D seismic reflection and a circumscribed 3-D magnetotelluric (MT) survey. This paper addresses the combination of the seismic and MT results, together with the available well-log data, in order to achieve a better characterization of the Hontomín subsurface. We compare the structural model obtained from the interpretation of the seismic data with the geoelectrical model resulting from the MT data. The models correlate well in the surroundings of the CO2 injection area with the major structural differences observed related to the presence of faults. The combination of the two methods allowed a more detailed characterization of the faults, defining their geometry, and fluid flow characteristics, which are key for the risk assessment of the storage site. Moreover, we use the well-log data of the existing wells to derive resistivity–velocity relationships for the subsurface and compute a 3-D velocity model of the site using the 3-D resistivity model as a reference. The derived velocity model is compared to both the predicted and logged velocity in the injection and monitoring wells, for an overall assessment of the computed resistivity–velocity relationships. The major differences observed are explained by the different resolution of the compared geophysical methods. Finally, the derived velocity model for the near surface is compared with the velocity model used for the static corrections in the seismic data. The results allowed extracting information about the characteristics of the shallow unconsolidated sediments, suggesting possible clay and water content variations. The good correlation of the velocity models derived from the resistivity–velocity relationships and the well-log data demonstrate the potential of the combination of the two methods for characterizing the subsurface, in terms of its physical properties (velocity, resistivity) and structural/reservoir characteristics. This work explores the compatibility of the seismic and magnetotelluric methods across scales highlighting the importance of joint interpretation in near surface and reservoir characterization.
A daily, 1-km resolution dataset of downscaled Greenland ice sheet surface mass balance (1958–2015)
Authors: Noël Brice , van de Berg Willem Jan , Machguth Horst , Lhermitte Stef , Howat Ian , Fettweis Xavier , van den Broeke Michiel R.
Published: June 2016

Abstract. This study presents a dataset of daily, 1-km resolution Greenland ice sheet (GrIS) surface mass balance (SMB) covering the period 1958–2015. Using elevation dependence, the high-resolution product is statistically downscaled from the native daily output of the polar regional climate model RACMO2.3 at 11-km. The dataset includes all individual SMB components projected to a down-sampled version of the Greenland Ice Mapping Project (GIMP) digital elevation model and ice mask. The 1-km mask better resolves narrow ablation zones, valley glaciers, fjords and disconnected ice caps. Relative to the 11-km product, the more detailed representation of confined glaciated areas leads to increased precipitation over the southeastern GrIS. In addition, the downscaled product shows a significant increase in runoff owing to better resolved low-lying marginal glaciated regions. The combined corrections for elevation and bare ice albedo markedly improve model agreement with a newly compiled dataset of ablation measurements.
Single questions: Multiple answers for multiple settings
Authors: Lloyd Margaret , Bahr Nan
Published: June 2016

The six papers in this issue of the Journal of Learning Design deal with some of the perennial questions facing educators and learning designers in higher education.  In this issue, university teachers in differing disciplines and from different institutions consider the questions that they find most perplexing. This includes wondering if putting lectures online will affect student attendance, how to set up group work to achieve a fair balance of skills and dispositions and if students have achieved the competency standards that we believe they have. One paper in this issue looks at how academics might meet to regularly and meaningfully share experiences while another asks how to get teaching staff enthusiastic about a new model of teaching, here problem-based learning in small group settings. One author takes a quite technical look at digital objects and works through how these characteristics can affect their learning potential. These are not isolated concerns and the wisdom of the authors in this issue will surely assist others in arriving at their own localised contextualised solutions
INSIGHTS INTO THE PREPARATION OF VINYL POLYBUTADIENE VIA COBALT-BASED CATALYST: TUNING ITS PROPERTIES BY THIOL-ENE MODIFICATION OF VINYL GROUP
Authors: Behera Prasanta Kumar , Mandal Prithwiraj , Maiti Madhuchhanda , Jasra Raksh Vir , Singha Nikhil K.
Published: June 2016

Elastomers with pendant alkenyl functionality can be easily modified using different types of postpolymerization reactions that lead to improved properties. This investigation reports the preparation of polybutadiene (PB) with control vinyl content by Co-based catalyst followed by modification of vinyl functionality via thiol-ene reaction. In this case, the polymerization of butadiene was carried out in cyclohexane using cobalt octanoate (Co[oct]2) in combination with diethylaluminium chloride (DEAC) and triethylaluminium (TEAL) as cocatalysts. The effects of different parameters, such as the concentration of catalyst and cocatalyst, monomer concentration, and reaction temperature on polymerization of butadiene (BD), were evaluated and optimized to obtain the desired vinyl content in the polymer. The microstructures in PB were investigated by 1H nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy analyses. Molecular weights and dispersity (Ð) of the polymers were determined by gel permeation chromatography analysis. The viscosity average molecular weight was calculated from the intrinsic viscosity [η] using the Mark-Houwink equation. Synthesized vinyl-PB was modified by the thiol-ene reaction using benzyl mercaptan as thiolating agent and 2,2′-azobis(isobutyronitrile) as an initiator. Thiol-ene modification was confirmed by 1H NMR analysis. Surface characteristics of thiol-modified PB were characterized by goniometer. Thiol-ene–modified PB showed greatly improved adhesive strength in metal–rubber bonding, as determined by lap shear test.
Wet kwaliteitsborging voor het bouwen; nieuw stelsel voor het bouwtoezicht
Authors: Ahraoui R.
Published: June 2016

Wet kwaliteitsborging voor het bouwen; nieuw stelsel voor het bouwtoezicht

Het langverwachte wetsvoorstel kwaliteitsborging voor het bouwen ter introductie van een nieuw stelsel van kwaliteitsborging voor het bouwen en versterking van de privaatrechtelijke positie van de bouwconsument is ingediend bij de Tweede Kamer. Bouwpartijen moeten bij het bouwen zelf voorzien in privaatrechtelijk georganiseerd toezicht om te voldoen aan het Bouwbesluit 2012. Dit heeft gevolgen voor het nalevingstoezicht door de gemeente. Ingegaan wordt op de gemaakte keuzes. Tevens wordt ingegaan op de verschillende mogelijkheden waarop het toezicht op de naleving van de regels en afspraken vorm krijgt in het nieuwe stelsel.
Treatment With Human Wharton's Jelly-Derived Mesenchymal Stem Cells Attenuates Sepsis-Induced Kidney Injury, Liver Injury, and Endothelial Dysfunction
Authors: Cóndor José M. , Rodrigues Camila E. , de Sousa Moreira Roberto , Canale Daniele , Volpini Rildo A. , Shimizu Maria H.M. , Camara Niels O.S. , Noronha Irene de L. , Andrade Lúcia
Published: June 2016

The pathophysiology of sepsis involves complex cytokine and inflammatory mediator networks. Downregulation of endothelial nitric oxide synthase contributes to sepsis-induced endothelial dysfunction. Human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) are known to reduce expression of proinflammatory cytokines and markers of apoptosis. We hypothesized that treatment with WJ-MSCs would protect renal, hepatic, and endothelial function in a cecal ligation and puncture (CLP) model of sepsis in rats. Rats were randomly divided into three groups: sham-operated rats; rats submitted to CLP and left untreated; and rats submitted to CLP and intraperitoneally injected, 6 hours later, with 1 × 106 WJ-MSCs. The glomerular filtration rate (GFR) was measured at 6 and 24 hours after CLP or sham surgery. All other studies were conducted at 24 hours after CLP or sham surgery. By 6 hours, GFR had decreased in the CLP rats. At 24 hours, Klotho renal expression significantly decreased. Treatment with WJ-MSCs improved the GFR; improved tubular function; decreased the CD68-positive cell count; decreased the fractional interstitial area; decreased expression of nuclear factor κB and of cytokines; increased expression of eNOS, vascular endothelial growth factor, and Klotho; attenuated renal apoptosis; ameliorated hepatic function; increased glycogen deposition in the liver; and improved survival. Sepsis-induced acute kidney injury is a state of Klotho deficiency, which WJ-MSCs can attenuate. Klotho protein expression was higher in WJ-MSCs than in human adipose-derived MSCs. Because WJ-MSCs preserve renal and hepatic function, they might play a protective role in sepsis.

Significance

Sepsis is the leading cause of death in intensive care units. Although many different treatments for sepsis have been tested, sepsis-related mortality rates remain high. It was hypothesized in this study that treatment with human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) would protect renal, hepatic, and endothelial function in a model of sepsis in rats. Treatment with WJ-MSCs improved the glomerular filtration rate, improved tubular function, decreased expression of nuclear factor κB and of cytokines, increased expression of eNOS and of Klotho, attenuated renal apoptosis, and improved survival. Sepsis-induced acute kidney injury is a state of Klotho deficiency, which WJ-MSCs can attenuate.
Stepwise Differentiation of Mesenchymal Stem Cells Augments Tendon-Like Tissue Formation and Defect Repair In Vivo
Authors: Yin Zi , Guo Jia , Wu Tian-yi , Chen Xiao , Xu Liang-liang , Lin Si-en , Sun Yun-xin , Chan Kai-Ming , Ouyang Hongwei , Li Gang
Published: June 2016

Tendon injuries are common and present a clinical challenge, as they often respond poorly to treatment and result in long-term functional impairment. Inferior tendon healing responses are mainly attributed to insufficient or failed tenogenesis. The main objective of this study was to establish an efficient approach to induce tenogenesis of bone marrow-derived mesenchymal stem cells (BMSCs), which are the most common seed cells in tendon tissue engineering. First, representative reported tenogenic growth factors were used as media supplementation to induce BMSC differentiation, and the expression of teno-lineage transcription factors and matrix proteins was compared. We found that transforming growth factor (TGF)-β1 significantly induced teno-lineage-specific gene scleraxis expression and collagen production. TGF-β1 combined with connective tissue growth factor (CTGF) elevated tenomodulin and Egr1 expression at day 7. Hence, a stepwise tenogenic differentiation approach was established by first using TGF-β1 stimulation, followed by combination with CTGF for another 7 days. Gene expression analysis showed that this stepwise protocol initiated and maintained highly efficient tenogenesis of BMSCs. Finally, regarding in situ rat patellar tendon repair, tendons treated with induced tenogenic BMSCs had better structural and mechanical properties than those of the control group, as evidenced by histological scoring, collagen I and tenomodulin immunohistochemical staining, and tendon mechanical testing. Collectively, these findings demonstrate a reliable and practical strategy of inducing tenogenesis of BMSCs for tendon regeneration and may enhance the effectiveness of cell therapy in treating tendon disorders.

Significance

The present study investigated the efficiency of representative tenogenic factors on mesenchymal stem cells' tenogenic differentiation and established an optimized stepwise tenogenic differentiation approach to commit tendon lineage differentiation for functional tissue regeneration. The reliable tenogenic differentiation approach for stem cells not only serves as a platform for further studies of underlying molecular mechanisms but also can be used to enhance cell therapy outcome in treating tendon disorders and develop novel therapeutics for tendon injury.
Bone Marrow Mesenchymal Stem Cell-Based Engineered Cartilage Ameliorates Polyglycolic Acid/Polylactic Acid Scaffold-Induced Inflammation Through M2 Polarization of Macrophages in a Pig Model
Authors: Ding Jinping , Chen Bo , Lv Tao , Liu Xia , Fu Xin , Wang Qian , Yan Li , Kang Ning , Cao Yilin , Xiao Ran
Published: June 2016

The regeneration of tissue-engineered cartilage in an immunocompetent environment usually fails due to severe inflammation induced by the scaffold and their degradation products. In the present study, we compared the tissue remodeling and the inflammatory responses of engineered cartilage constructed with bone marrow mesenchymal stem cells (BMSCs), chondrocytes, or both and scaffold group in pigs. The cartilage-forming capacity of the constructs in vitro and in vivo was evaluated by histological, biochemical, and biomechanical analyses, and the inflammatory response was investigated by quantitative analysis of foreign body giant cells and macrophages. Our data revealed that BMSC-based engineered cartilage suppressed in vivo inflammation through the alteration of macrophage phenotype, resulting in better tissue survival compared with those regenerated with chondrocytes alone or in combination with BMSCs. To further confirm the macrophage phenotype, an in vitro coculture system established by engineered cartilage and macrophages was studied using immunofluorescence, enzyme-linked immunosorbent assay, and gene expression analysis. The results demonstrated that BMSC-based engineered cartilage promoted M2 polarization of macrophages with anti-inflammatory phenotypes including the upregulation of CD206, increased IL-10 synthesis, decreased IL-1β secretion, and alterations in gene expression indicative of M1 to M2 transition. It was suggested that BMSC-seeded constructs have the potential to ameliorate scaffold-induced inflammation and improve cartilaginous tissue regeneration through M2 polarization of macrophages.

Significance

Finding a strategy that can prevent scaffold-induced inflammation is of utmost importance for the regeneration of tissue-engineered cartilage in an immunocompetent environment. This study demonstrated that bone marrow mesenchymal stem cell (BMSC)-based engineered cartilage could suppress inflammation by increasing M2 polarization of macrophages, resulting in better tissue survival in a pig model. Additionally, the effect of BMSC-based cartilage on the phenotype conversion of macrophages was further studied through an in vitro coculture system. This study could provide further support for the regeneration of cartilage engineering in immunocompetent animal models and provide new insight into the interaction of tissue-engineered cartilage and macrophages.
La diversité, la répartition et l’écologie du complexe d’espèces cryptiques Euytemora affinis, dans la zone d’alevinage de l’estuaire moyen du Saint-Laurent
Authors: Winkler Gesche , Cabrol Jory , Favier Jean-Baptiste
Published: June 2016

Le copépode calanoïde Eurytemora affinis est un complexe d’espèces clés des réseaux trophiques estuariens. En dominant les communautés planctoniques dans la plupart des estuaires de l’hémisphère nord, E. affinis permet un transfert d’énergies vers les niveaux trophiques supérieurs. Il influence directement le recrutement des espèces de poissons et constitue une espèce clé des zones d’alevinage. E. affinis est en réalité un complexe d’espèces cryptiques composé de 6 clades morphologiquement similaires, mais possédant des histoires évolutives distinctes. Dans la zone de transition estuarienne du Saint-Laurent, 2 clades (Atlantique et Nord-Atlantique) sympatriques, spatialement ségrégués, dominent la communauté zooplanctonique. Chacun des 2 clades semble exploiter différents types d’habitats en fonction de sa tolérance physiologique à la salinité et à la disponibilité de nourriture. Nous discuterons des études récentes en mettant l’accent sur la répartition, la différenciation génétique, mais aussi l’écologique de ces espèces du complexe d’E. affinis afin de mieux comprendre leurs influences respectives sur le fonctionnement et la productivité de l’écosystème unique que représente la zone d’alevinage de l’estuaire du Saint-Laurent.