3,447 research outputs found
Asymmetric Hydrogenation in Water by a Rhodium Complex of Sulfonated 2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl (binap)
The synthesis of sulfonated 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (binap) is reported; a rhodium complex of this ligand is the first to perform asymmetric hydrogenation in neat water with optical yields as high as those obtained in nonaqueous solvent
Application of Risk Informed Decision Making to Highly Reliable Three Dimensionally Woven Thermal Protection System for Mars Sample Return
The NASA Risk Informed Decision Making process is used to assess a trade space of three dimensionally woven thermal protection systems for application to the Mars Sample Return Earth Entry Vehicle. Candidate architectures are assessed based on mission assurance, technical development, cost, and schedule risk. Assessment methodology differed between the architectures, utilizing a four-point quantitative scale for mission assurance and technical development and highly tailored PERT techniques for cost and schedule. Risk results are presented, in addition to a review of RIDM effectiveness for this application
A Bayesian regression tree approach to identify the effect of nanoparticles' properties on toxicity profiles
We introduce a Bayesian multiple regression tree model to characterize
relationships between physico-chemical properties of nanoparticles and their
in-vitro toxicity over multiple doses and times of exposure. Unlike
conventional models that rely on data summaries, our model solves the low
sample size issue and avoids arbitrary loss of information by combining all
measurements from a general exposure experiment across doses, times of
exposure, and replicates. The proposed technique integrates Bayesian trees for
modeling threshold effects and interactions, and penalized B-splines for dose-
and time-response surface smoothing. The resulting posterior distribution is
sampled by Markov Chain Monte Carlo. This method allows for inference on a
number of quantities of potential interest to substantive nanotoxicology, such
as the importance of physico-chemical properties and their marginal effect on
toxicity. We illustrate the application of our method to the analysis of a
library of 24 nano metal oxides.Comment: Published at http://dx.doi.org/10.1214/14-AOAS797 in the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Experimental determination of distance and orientation of metallic nanodimers by polarization dependent plasmon coupling
Live cell imaging using metallic nanoparticles as tags is an emerging
technique to visualize long and highly dynamic processes due to the lack of
photobleaching and high photon rate. However, the lack of excited states as
compared to fluorescent dyes prevents the use of resonance energy transfer and
recently developed super resolution methods to measure distances between
objects closer that the resolution limit. In this work, we experimentally
demonstrate a technique to determine subdiffraction distances based on the near
field coupling of metallic nanoparticles. Due to the symmetry breaking in the
scattering cross section, not only distances but also relative orientations can
be measured. Gold nanoparticles were prepared on glass in such way that a small
fraction of dimers was present. The sample was sequentially illuminated with
two wavelengths to separate background from nanoparticle scattering based on
their spectral properties. A novel total internal reflection illumination
scheme in which the polarization can be rotated was used to further minimize
background contributions. In this way, radii, distance and orientation were
measured for each individual dimer and their statistical distributions were
found to be in agreement with the expected ones. We envision that this
technique will allow fast and long term tracking of relative distance and
orientation in biological processes.Comment: 9 pages, 5 figures, Commentary from the reviewer available in Papers
in Physic
Who pays the taxes?
The European Union is legally entitled to the revenue from (1) agricultural and sugar levies, (2) customs duties, (3) a 1 percent rate on each Member States' value added tax base, and (4) a resource on the basis of GNP. Currently, the Union is actively involved in the search for a fifth own revenue source. Therefore, the European Commission (DG XIX) has invited the authors to trace 'who pays the taxes'. As requested, our report gives a general account of methods to investigate impacts of taxation. More specifically, we have estimated the incidence of national tax systems (Germany, the Netherlands, Spain and the United Kingdom), and the incidence of present own resources and prospective new (tax) resources of the European Union. Up till now, such information was not (readily) available.tax incidence in the European Union, prospective new EU tax resources
Lip Localization Algorithm Using Gabor Filters
This paper describes a lip localization algorithm within a still image frame for subsequent tracking and audiovisual speech recognition processing. A Gabor filter-based feature space is promoted as a means to localize lips within an image based off of shape. This filtered space is shown to effectively differentiate facial features, including lips, from their backgrounds and to bound the full extent of the lips within a face-classified region of interest. Extensive training and test sets are used to justify design decisions and performance
Impact of External Pressures on Information Security Policy Compliance in the Banking Industry
There has been virtually no previous study discussing how external pressures impel banks to stay compliant. These external pressures could be a compelling force driving banks to comply. Hinged on the Neo-Institutional Theory (NIT), this study examines how the external pressures, namely, regulative, normative, and cognitive expectations, drive banks to comply. The research findings reveal that information security policy compliance in banking organizations is directly driven by normative expectation. Normative expectation encompasses the pressures of fulfilling social/moral obligation and conforming to the industry norms defined by the standardized information security mechanisms. Since the findings uncover that normative expectation is a significant force in the institution of banking, this study suggests drafting internal organizational policies to (1) meet normative expectation and (2) provide a new avenue for risk assessment based on the normative elements
Who pays the taxes?
The European Union is legally entitled to the revenue from (1) agricultural and sugar levies, (2) customs duties, (3) a 1 percent rate on each Member States' value added tax base, and (4) a resource on the basis of GNP. Currently, the Union is actively involved in the search for a fifth own revenue source. Therefore, the European Commission (DG XIX) has invited the authors to trace 'who pays the taxes'. As requested, our report gives a general account of methods to investigate impacts of taxation. More specifically, we have estimated the incidence of national tax systems (Germany, the Netherlands, Spain and the United Kingdom), and the incidence of present own resources and prospective new (tax) resources of the European Union. Up till now, such information was not (readily) available.tax incidence in the European Union, prospective new EU tax resources
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