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A number of publications have discussed approaches to training the scientific workforce in comparative effectiveness research (CER) and patient-centered outcomes research (PCOR). To meet this need, funders have offered resources for developing educational materials and establishing training programs. To extend these efforts into specific researcher communities, the Agency for Healthcare Research and Quality developed an R25 Funding Opportunity Announcement that called for basic, advanced, and experiential training for a specific researcher community in collaboration with associated program partners. This paper describes the strategies developed by the 5 subsequently funded programs, their specific researcher communities and program partners, and the challenges associated with developing in-person and online programs. We focus on lessons learned that can be translated into developing training programs nationwide and on training for the special populations of interest. We also discuss the creation of a sustainable network for training and the conduct of comparative effectiveness research/patient-centered outcomes research in targeted communities.
Symbiotic objects are related to planetary nebulae in that they represent late stages of stellar evolution. They are interacting binary systems where a hot companion star ionizes the stellar wind of a red giant. This configuration offers the unique possibility for deriving elemental abundances for cool giants from a nebular spectrum with the diagnostic tools employed for HII regions. The analysis can be applied to different types of symbiotic systems having a G, K or M giant, a Mira variable or a carbon star as cool component. The great advantage of this technique is, that it does not depend on stellar parameters or molecular data, and that it can therefore be used as a test or an alternative for the traditional photospheric abundance determinations.
This study aimed to link expression patterns of AQP1, AQP5, Bcl-2 and p16 to clinicopathological characteristics of oro-hypopharyngeal squamous cell carcinomas.
Immunohistochemical expression of AQP1, AQP5, Bcl-2 and p16 was investigated in 107 consecutive oro-hypopharyngeal squamous cell carcinoma cases. Molecular interrelationship and correlations with clinicopathological parameters and survival were computed.
AQP1 was expressed exclusively by a subgroup of basaloid-like squamous cell carcinomas. AQP5 was detected in 25.2 per cent of the samples, showing significant association with the absence of p16 and Bcl-2 (p = 0.018; p = 0.010). In multivariate analysis, overexpression of p16 was significantly correlated with favourable overall survival (p = 0.014).
AQP5 defined a subset of patients with Bcl-2-negative and p16-negative tumours with a poor clinical outcome. AQP1 was found to be a marker of a subgroup of aggressive basaloid-like squamous cell carcinomas. These findings suggest that AQP1 and AQP5 are interesting candidates for further studies on risk group classification and personalised treatment of oro-hypopharyngeal squamous cell carcinomas.
SPHERE, the Spectro-Polarimetric High-contrast Exoplanet REsearch instrument for the VLT
is optimized towards reaching the highest contrast in a limited field of view and at short
distances from the central star, thanks to an extreme AO system. SPHERE is very well
suited to study the close environment of Betelgeuse, and has a strong potential for
detecting the ejection activity around this key red supergiant.
The objective of the present study was to compare the performance of seven different, widely applied crop models in predicting heat and drought stress effects. The study was part of a recent suite of model inter-comparisons initiated at European level and constitutes a component that has been lacking in the analysis of sources of uncertainties in crop models used to study the impacts of climate change. There was a specific focus on the sensitivity of models for winter wheat and maize to extreme weather conditions (heat and drought) during the short but critical period of 2 weeks after the start of flowering. Two locations in Austria, representing different agro-climatic zones and soil conditions, were included in the simulations over 2 years, 2003 and 2004, exhibiting contrasting weather conditions. In addition, soil management was modified at both sites by following either ploughing or minimum tillage. Since no comprehensive field experimental data sets were available, a relative comparison of simulated grain yields and soil moisture contents under defined weather scenarios with modified temperatures and precipitation was performed for a 2-week period after flowering. The results may help to reduce the uncertainty of simulated crop yields to extreme weather conditions through better understanding of the models’ behaviour. Although the crop models considered (DSSAT, EPIC, WOFOST, AQUACROP, FASSET, HERMES and CROPSYST) mostly showed similar trends in simulated grain yields for the different weather scenarios, it was obvious that heat and drought stress caused by changes in temperature and/or precipitation for a short period of 2 weeks resulted in different grain yields simulated by different models. The present study also revealed that the models responded differently to changes in soil tillage practices, which affected soil water storage capacity.
The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 μm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits.
The concentration and temperature dependence of the self-diffusion of benzene adsorbed in the metal-organic framework MOF-5 (IRMOF-1) is studied by pulsed field gradient (PFG) NMR spectroscopy. When increasing the loading from 10 to 20 molecules per unit cell of MOF-5, the experimental diffusion data drop by a factor of about 3 while current molecular dynamic (MD) simulations predict slightly increasing diffusion coefficients for this range of loadings. The observation is rationalized using the recently predicted clustering of adsorbate molecules in microporous systems for temperatures well below the adsorbate critical temperature. Necessary improvements of molecular simulation models for predicting diffusivities under such conditions are discussed.
Solid Oxide Fuel Cells (SOFC) are high temperature energy converters. When an SOFC is operated for the rst time, a substantial increase in cell performance is observed which is caused by microstructural changes at the cathode/electrolyte interface. To optimize the resulting formation of the interface, a dynamic model is required that represents the relations between materials compositions, operating conditions, electric current, and microstructure.
Building a model based on chemical reaction equations fails because of the high complexity of the interface reactions. Therefore, this contribution presents an interdisciplinary approach to modeling in materials development by applying computational intelligence techniques. Qualitative models are used to formalize the expert knowledge about the irreversible materials changes at the cathode/electrolyte interface. Fuzzy if-then rules represent the dynamic behavior of the microstructural formation. The resulting model enables the application of simulations instead of time-consuming experiments and thus allows the systematic optimization of the startup process.
The body implant interaction is strongly affected by the implant surface structure and chemistry [1,2]. Thus by applying a nanoporous coating to metallic implants the implant surface can be adjusted to different needs. Compared to biological molecules the size of the pores is so small (between 5 nm and 250 nm) that the cellular response to this surface modification is not affected by the structure itself. Nevertheless by loading the pores with bioactive molecules it is possible to achieve a new kind of active implants surfaces for soft and hard tissue implants. With this coating it is possible to irreversibly bind radioactive isotopes like 99mTc, 186/188Re, 103Pd, and many more for local radiotherapy onto soft tissue implants like stents or seeds.
Powders of pure silicon and gallium arsenide were reacted with molten silicate glass of a composition used in our prior work on CdS and CdTe quantum dots in glass [1–4]. After the Si or GaAs agglomerated particles had reacted with the melt for an hour, the material was solidified to obtain a gray-black glass. Ground powders of this glass were again mixed with additional base glass powders to dilute the concentration of the semiconductor, remelted, and cast into glass. Samples of silicon-in-glass showing green photoluminescence peaked at 530 nm were obtained. The GaAs-in-glass samples show absorption features in the optical spectra which suggest the possibility of quantum confinement.
We studied by deep level transient spectroscopy (DLTS) and capacitance-voltage (CV) measurements the effects of doping (Zn, S), nitrogen implantation and annealing of n-type GaN grown on sapphire by MOVPE. The DLTS spectra of the as grown samples show two defect levels which are assumed to be identical with recently reported levels [10, 11]. In N-implanted GaN a third level is introduced which is not detectable in our as grown samples. This levels concentration follows the increasing N-implantation density. The depth profiles of its concentration correlate with the distribution of implantation defects expected from Monte-Carlo simulation. After annealing at 900°C for 60s the additional defect level vanishes. The DLTS spectrum then resembles those of annealed as grown samples. The n-type carrier concentration (CV measurements) increases in samples with low N-implantation dose. This implantation effect can be removed also with the RTA step. The increasing carrier concentration provides evidence that the N vacancy is a donor in GaN. For Zn and S doped GaN deep defect levels has been found, which are reported here.
Films and monoliths, containing clusters (sizes < 5 nm) of the binary semiconductor CdS and sandwiched CdS-PbS, were prepared via multifunctional inorganic-organic sol-gel processing. As a sulfur source, hexamethyldisilylthiane was employed. In precursor sols, the metal sulfide clusters are carrying functionalized silanes acting as stabilizing centers as well as inorganic and organic network formers. Hydrolysis and condensation produces an inorganic network yielding viscous liquids useful to prepare optically transparent films or monoliths. The final organic cross-linking at T < 100°C results in materials of variable spectral response, thickness and optical density. In preliminar degenerate four-wave mixing experiments, self-diffraction from laser-induced gratings was observed on unsupported 200 μm thick CdS-PbS doped monoliths. The maximum first order grating efficiency, measured at different wavelengths between 490 and 520 nm, was 0.5 · 10−3 and the corresponding calculated effective third order susceptibility was of the order of 10−9 esu.
We present an EXAFS study of the local environment of Co dopant atoms in nanocrystalline Cu. Due to the low solubility of Co atoms in bulk Cu, these measurements yield information on the local atomic structure of grain boundaries in nanocrystalline Cu. Previous EXAFS studies on pure nanocrystalline metals have indicated an atomic arrangement in the grain boundary component exhibiting a broad distribution of interatomic spacings which differs from the atomic structure of the crystalline or glassy state. In the present investigation a significantly reduced coordination number around Co is found; also, the first shell bond length varies with dopant concentration from that typical of Co substitutional impurities in Cu to that of bulk Co. These results suggest that Co atoms substitute Cu atoms both in the disordered grain boundaries and in the lattice of the Cucrystallites and/or form Co-precipitates.
Our system is the electrochemical approaches include the detection of hybridization from nonlabeling nucleic acids to protein-bound nucleic acids using soluble mediators with K4Fe(CN)6 solutions. In order to generate bio-functional surfaces, the streptavidin(SAv)-biotin system is used. A 50 % change of redox peak current after hybridization measured with 50 μM concentration of target DNA. We suggest that this result comes from the efficient electron transport through the SAv-biotin interaction. Our electrochemical detection system showed good reproducibility on a chip with non-labeling DNA hybridization detection.