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A multiscale simulation, data assimilation, forecasting system was developed in support of the SPURS-2 (Salinity Processes in the Upper-ocean Regional Study 2) field campaign. Before the field campaign, a multiyear simulation was produced for characterizing variabilities in upper-ocean salinity, eddy activity, and other parameters and for illustrating major processes that control the region's upper-ocean salinity at different spatial and temporal scales. This simulation assisted in formulating sampling plans. During the field experiment, the system integrated SPURS-2 measurements with those from routine operational observing networks, including Argo floats and satellite surface temperatures, salinities, and heights, and provided real-time skillful daily forecasts of ocean conditions. Forecast reports were prepared to summarize oceanic conditions and multiscale features and were delivered to the SPURS-2 chief scientist and other SPURS-2 investigators through the SPURS-2 Information System. After the field experiment, the data assimilation system was used to produce a reanalysis product to help quantify contributions of different processes to salinity variability in the region. [ABSTRACT FROM AUTHOR]

To determine the effect of adipose-derived stem cells (ADSCs) added to bone marrow-derived mesenchymal stem cell (MSC) sheets on bone formation at an ectopic site. We isolated MSCs and ADSCs from the same rabbits. We then prepared MSC sheets for implantation with or without ADSCs subcutaneously in the backs of severe combined immunodeficiency (SCID) mice. We assessed bone formation at eight weeks after implantation by micro-computed tomography and histological analysis. In osteogenic medium, MSCs grew to form multilayer sheets containing many calcium nodules. MSC sheets without ADSCs formed bone-like tissue; although neo-bone and cartilage-like tissues were sparse and unevenly distributed by eight weeks after implantation. In comparison, MSC sheets with ADSCs promoted better bone regeneration as evidenced by the greater density of bone, increased mineral deposition, obvious formation of blood vessels, large number of interconnected ossified trabeculae and woven bone structures, and greater bone volume/total volume within the composite constructs. Our results indicate that although sheets of only MSCs have the potential to form tissue engineered bone at an ectopic site, the addition of ADSCs can significantly increase the osteogenic potential of MSC sheets. Thus, the combination of MSC sheets with ADSCs may be regarded as a promising therapeutic strategy to stimulate bone regeneration. [ABSTRACT FROM AUTHOR]

A three-dimensional variational data assimilation (3DVAR) scheme has been developed within the framework of the Regional Ocean Modeling System (ROMS). This ROMS3DVAR enables the capability of predicting meso- to small-scale variations with temporal scales from hours to days in coastal oceans. To cope with particular difficulties that result from complex coastlines and bottom topography, unbalanced flows, and sparse observations, ROMS3DVAR includes novel strategies. These strategies include the implementation of three-dimensional anisotropic and inhomogeneous error correlations based on a Kronecker product, application of particular weak dynamic constraints, and implementation of efficient and reliable algorithms for minimizing the cost function. The formulation of ROMS3DVAR is presented here, and its implementation off the West Coast is currently under way. [ABSTRACT FROM AUTHOR]

An algorithm is proposed for the computation of streamfunction and velocity potential from given horizontal velocity vectors based on solving a minimization problem. To guarantee the uniqueness of the solution and computational reliability of the algorithm, a Tikhonov regularization is applied. The solution implies that the obtained streamfunction and velocity potential have minimal magnitude, while the given velocity vectors can be accurately reconstructed from the computed streamfunction and velocity potential. Because the formulation of the minimization problem allows for circumventing the explicit specification of separate boundary conditions on the streamfunction and velocity potential, the algorithm is easily applicable to irregular domains. By using an advanced minimization algorithm with the use of adjoint techniques, the method is computationally efficient and suitable for problems with large dimensions. An example is presented for coastal oceans to illustrate the practical application of the algorithm. [ABSTRACT FROM AUTHOR]

Analysis of singular vectors (SVs) is performed on the Florida State University Global Spectral Model, which includes linearized full physics of the atmosphere. It is demonstrated that the physical processes, especially precipitation, fundamentally affect the leading SVs. When the SVs are coupled with the precipitation geographically, their growth rates increase substantially and their structures change significantly. The physical processes however have little impact on growth rates or structures of the SVs that are geographically independent of precipitation. Furthermore, it is shown that spatial filtering along with the projection operator that projects the flow winds to the rotational wind (designed as a simple initialization process) improves the structural features of SVs and is found to mitigate spurious modes. [ABSTRACT FROM AUTHOR]

On the basis of the datasets obtained for the monthly turbulent heat flux (1984-2009) from the Objectively Analyzed Air-Sea Heat Flux (OAFlux), the radiation flux from the International Satellite Cloud Climatology Project (ISCCP), the variability characteristics of the net heat flux (Qnet) over the Kuroshio System (KS) and its relationship with the climate in China were studied. The results reveal that except for a steady enhancement in the period 1984-2009, the boreal winter Qnet over the KS is characterized by obvious interannual variation of the period quasi-5 year as well as decadal variability shifting from negative to positive anomalies in the mid-1990s. In the wintertime, the increasing KS Qnet is primarily responsible for the intensification of the East Asia winter monsoon (EAWM) via a deepening of the Aleutian low and an enhancement of the Siberia high and has a correlation coefficient of 0.72 with a 1-month delay. The enhanced-EAWM induces colder winters in Northeast China and higher Qnet over the KS by carrying significantly greater amounts of cold air mass. During the low Qnet winter, the EAWM is weakened, and the southwesterly wind that contains abundant water vapour enhances and pushes toward southern China, thereby bringing heavier rainfall. The anomalous Qnet over the KS in the wintertime lasts until the following spring with a weaker relative intensity. In the spring after the low KS Qnet winter, the anomalous easterly wind transfers colder air masses from the Sea of Japan to the North China and Yellow-Huaihe regions and then cools these regions. The warmer and wetter southwesterlies along the northwestern flank of the anomalous anticyclone east of Taiwan Island meet these colder easterlies accompanied by an anomalous upward motion, thereby inducing an anomalous northwest-southeast precipitation band in the central and eastern region of China, especially in the Yangtze-Huaihe region. [ABSTRACT FROM AUTHOR]

We developed the data management system for the US National Aeronautics and Space Administration-sponsored Salinity Processes in the Upper-ocean Regional Study (SPURS) Atlantic field campaign (SPURS-1). Data management support means more than simply collecting and archiving static data sets. It involves a complex mixture of data visualization, interaction with principal investigators, Web development, public outreach, quality assurance, and archiving for posterity. [ABSTRACT FROM AUTHOR]

We report the use of a 3-dimensional variational (3DVAR) data assimilation method as part of a numerical model off northern Chile. The numerical model is part of an ocean forecasting project that aims to understand the impact of environmental variability on the distribution of biological species in the area. We assimilated data from a simulated ocean observing system to recover a known state, obtaining a significantly smaller error when compared to a numerical run with no assimilation. Our results validate the computational implementation of the code, and allow us to evaluate the impact of the choice of data in the assimilation process: the assimilation of sea surface height being particularly important. We note that the assimilation of surface data propagates properly to greater depths and reduces the error with reference to the known state. This was possible by using covariance error matrices calculated previously for the California coastal area. The implementation of the data assimilation module is relatively simple and permits its use in operational forecasting systems, and for the design and evaluation of future ocean observational systems. [ABSTRACT FROM AUTHOR]

Er3+–Yb3+-codoped titania–zirconia composites were synthesized using a coprecipitation method with aqueous ammonia as the precipitator. Their crystal structures and upconversion luminescent properties were investigated using X-ray diffraction and photoluminescence spectra. The strong green and red upconversion emissions were observed. The ratio of green to red emission was changed with the variation of the host composition and dopant concentrations. The relevant mechanism was discussed. [ABSTRACT FROM AUTHOR]

Balance constraints are important for background error covariance (BEC) in data assimilation to spread information between different variables and produce balance analysis fields. Using statistical regression, we develop a balance constraint for the BEC of aerosol variables and apply it to a three-dimensional variational data assimilation system in the WRF/Chem model; 1-month forecasts from the WRF/Chem model are employed for BEC statistics. The cross-correlations between the different species are generally high. The largest correlation occurs between elemental carbon and organic carbon with as large as 0.9. After using the balance constraints, the correlations between the unbalanced variables reduce to less than 0.2. A set of data assimilation and forecasting experiments is performed. In these experiments, surface PM2.5 concentrations and speciated concentrations along aircraft flight tracks are assimilated. The analysis increments with the balance constraints show spatial distributions more complex than those without the balance constraints, which is a consequence of the spreading of observation information across variables due to the balance constraints. The forecast skills with the balance constraints show substantial and durable improvements from the 2nd hour to the 16th hour compared with the forecast skills without the balance constraints. The results suggest that the developed balance constraints are important for the aerosol assimilation and forecasting. [ABSTRACT FROM AUTHOR]