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Agonistic Autoantibodies to the a 1 -Adrenergic Receptor and the b 2 -Adrenergic Receptor in Alzheimer's and Vascular Dementia
No full textInfluence of the nucleus area distribution on the survival fraction after charged particles broad beam irradiation Running Head: Influence of nucleus area distribution on survival fraction
No full textAbstract It is well known that broad beam irradiation with heavy ions leads to variation of the number of hit (s) received by each cell as the distribution of particles follows the Poisson statistics. Although the nucleus area will determine the number of hit(s) received for a given dose, the variation in the nucleus area amongst the irradiated cell population is generally not considered. In this work, we investigate the effect of the nucleus area distribution on the survival fraction. More specifically, this work aims to explain the deviation or tail which might be observed in the survival fraction at high irradiation doses. For this purpose, the nucleus area distribution was added to the beam Poisson statistics and the LinearQuadratic model in order to fit the experimental data generated by broad beam irradiation with high energy heavy ions. As shown in this study, the nucleus size variation and the associated Poisson statistics can lead to an upward bending in the survival fraction after broad beam irradiation. The influence of the distribution parameters (mean area and standard deviation) were studied using a normal distribution. The influence of the Linear-Quadratic model parameters ( and ) is also shown. Finally, the model proposed here was successfully tested to the survival fraction of LN18 cells irradiated with a 85 keV/µm carbon ion broad beam for which the distribution in the area of the nucleus had been determined
Antiferromagnetic fluctuations in CePdSn Kondo compound from Mössbauer spectroscopy
No full textAbstract 119 Sn Mössbauer spectroscopy was used to study the fluctuations of antiferromagnetic domains in the heavy-fermion CePdSn Kondo compound. The temperature evolution of the experimental spectra was described within both two-and multi-level relaxation models. The difference between these two approaches is discussed. The temperature dependence of the relaxation rate of the domain's magnetization and the density of itinerant electrons near the tin atoms are investigated
Synthesis and Characterization of Acrylamide-Based Anionic Copolymer and Investigation of Solution Properties
No full textThe copolymer of acrylamide (AM) and 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) was synthesized through radical solution polymerization by potassium persulfate as initiator. By changing the AMPS feed ratio from 10 to 70%, and keeping other reaction conditions constant, different copolymers were synthesized. The techniques of Fourier transform infrared (FTIR) and nuclear magnetic resonance ( 1 H-13 C-NMR) spectroscopy were used for identification of functional groups and confirmation of copolymers' structure. Intrinsic and apparent viscosity of samples were measured in aqueous sodium chloride solution under standard conditions. The anionic degree of copolymers was determined by back titration method and by 13 C-NMR spectroscopy. Molecular weight of copolymers was determined by the Mark-Houwink relationship. The measured molecular weight of samples showed that we have acquired a high molecular weight product. The effect of different range of shear rates on solution viscosity was evaluated. The copolymer solutions showed non-Newtonian shear thinning behavior. The performance of copolymers with respect to shear resistance and molecular weight was evaluated from industry application standpoint
No full textABSTRACT Exploration work at the Gorleben salt dome has been carried out since 1977 to investigate the site regarding its suitability as a final repository for high-level radioactive wastes. In the framework of the "Preliminary Safety Analysis of the Gorleben Site" a comprehensive assessment is being performed with focus on long-term safety. Because the integrity of the geological barrier is crucial for protection from damage caused by ionising radiation during the post-operational phase, 2D and 3D thermo-mechanical calculations for a reference section through the salt dome were carried out, all looking at two different waste emplacement concepts: emplacement in drifts and in boreholes. The calculated stresses are the basis for evaluating the barrier integrity on the basis of the dilatancy criterion and the fluid pressure criterion
15+ MILLION TOP 1% MOST CITED SCIENTIST 12.2% AUTHORS AND EDITORS FROM TOP 500 UNIVERSITIES 31 Ethanol Interference on Adenosine System
No full textHydrologic and Water Quality Integration Tool: HydroWAMIT
No full textAbstract: A spatially distributed and continuous hydrologic model focusing on total maximum daily load ͑TMDL͒ projects was developed. Hydrologic models frequently used for TMDLs such as the hydrologic simulation program-FORTRAN ͑HSPF͒, soil and water assessment tool ͑SWAT͒, and generalized watershed loading function ͑GWLF͒ differ considerably in terms of spatial resolution, simulated processes, and linkage flexibility to external water quality models. The requirement of using an external water quality model for simulating specific processes is not uncommon. In addition, the scale of the watershed and water quality modeling, and the need for a robust and cost-effective modeling framework justify the development of alternative watershed modeling tools for TMDLs. The hydrologic and water quality integration tool ͑HydroWAMIT͒ is a spatially distributed and continuous time model that incorporates some of the features of GWLF and HSPF to provide a robust modeling structure for TMDL projects. HydroWAMIT operates within the WAMIT structure, developed by Omni Environmental LLC for the Passaic River TMDL in N. J. HydroWAMIT is divided into some basic components: the hydrologic component, responsible for the simulation of surface flow and baseflow from subwatersheds; the nonpointsource ͑NPS͒ component, responsible for the calculation of the subwatershed NPS loads; and the linkage component, responsible for linking the flows and loads from HydroWAMIT to the water quality analysis simulation program ͑WASP͒. HydroWAMIT operates with the diffusion analogy flow model for flow routing. HydroWAMIT provides surface runoff, baseflow and associated loads as outputs for a daily timestep, and is relatively easy to calibrate compared to hydrologic models like HSPF. HydroWAMIT assumes that the soil profile is divided into saturated and unsaturated layers. The water available in the unsaturated layer directly affects the surface runoff from pervious areas. Surface runoff from impervious areas is calculated separately according to precipitation and the impervious fractions of the watershed. Baseflow is given by a linear function of the available water in the saturated zone. The utility of HydroWAMIT is illustrated for the North Branch and South Branch Raritan River Watershed ͑NSBRW͒ in New Jersey. The model was calibrated, validated, and linked to the WASP. The NPS component was tested for total dissolved solids. Available weather data and point-source discharges were used to prepare the meteorological and flow inputs for the model. Digital land use, soil type datasets, and digital elevation models were used for determining input data parameters and model segmentation. HydroWAMIT was successfully calibrated and validated for monthly and daily flows for the NSBRW outlet. The model statistics obtained using HydroWAMIT are comparable with statistics of HSPF and SWAT applications for medium and large drainage areas. The results show that HydroWAMIT is a feasible alternative to HSPF and SWAT, especially for large-scale TMDLs that require particular processes for water quality simulation and minor hydrologic model calibration effort