29,213 research outputs found
Rectifiability of Optimal Transportation Plans
The purpose of this note is to show that the solution to the Kantorovich
optimal transportation problem is supported on a Lipschitz manifold, provided
the cost is with non-singular mixed second derivative. We use this
result to provide a simple proof that solutions to Monge's optimal
transportation problem satisfy a change of variables equation almost
everywhere
Space-efficient Feature Maps for String Alignment Kernels
String kernels are attractive data analysis tools for analyzing string data.
Among them, alignment kernels are known for their high prediction accuracies in
string classifications when tested in combination with SVM in various
applications. However, alignment kernels have a crucial drawback in that they
scale poorly due to their quadratic computation complexity in the number of
input strings, which limits large-scale applications in practice. We address
this need by presenting the first approximation for string alignment kernels,
which we call space-efficient feature maps for edit distance with moves
(SFMEDM), by leveraging a metric embedding named edit sensitive parsing (ESP)
and feature maps (FMs) of random Fourier features (RFFs) for large-scale string
analyses. The original FMs for RFFs consume a huge amount of memory
proportional to the dimension d of input vectors and the dimension D of output
vectors, which prohibits its large-scale applications. We present novel
space-efficient feature maps (SFMs) of RFFs for a space reduction from O(dD) of
the original FMs to O(d) of SFMs with a theoretical guarantee with respect to
concentration bounds. We experimentally test SFMEDM on its ability to learn SVM
for large-scale string classifications with various massive string data, and we
demonstrate the superior performance of SFMEDM with respect to prediction
accuracy, scalability and computation efficiency.Comment: Full version for ICDM'19 pape
Intervención en un sistema de conducta
Los autores presentan algunos factores importantes que pueden ayudar a cambiar la interacción de pareja e interpersonal. Recuperando el concepto de sistema de conducta, insisten en identificar y sobre todo en modos de intervención en cada sistema a través de una serie de herramientas comunicativas e interpersonales.The authors present some important factors which can help to change interpersonal and couple interactions. Retrieving the concept of system of behaviour they insist on identifying and intervening in each system through a series of communicative and interpersonal tools.Les auteurs présentent quelques aspects d’importance que peuvent aider à changer les interactions du couple et interpersonnels. Récupérant le concept de système conductuel ils mettent l’accent dans l’identification et l’intervention sur ces systèmes, à travers d’une série d’éléments communicatifs et interpersonnels
First-principles kinetic Monte Carlo simulations for heterogeneous catalysis, applied to the CO oxidation at RuO2(110)
We describe a first-principles statistical mechanics approach enabling us to
simulate the steady-state situation of heterogeneous catalysis. In a first step
density-functional theory together with transition-state theory is employed to
obtain the energetics of all relevant elementary processes. Subsequently the
statistical mechanics problem is solved by the kinetic Monte Carlo method,
which fully accounts for the correlations, fluctuations, and spatial
distributions of the chemicals at the surface of the catalyst under
steady-state conditions. Applying this approach to the catalytic oxidation of
CO at RuO2(110), we determine the surface atomic structure and composition in
reactive environments ranging from ultra-high vacuum (UHV) to technologically
relevant conditions, i.e. up to pressures of several atmospheres and elevated
temperatures. We also compute the CO2 formation rates (turnover frequencies).
The results are in quantitative agreement with all existing experimental data.
We find that the high catalytic activity of this system is intimately connected
with a disordered, dynamic surface ``phase'' with significant compositional
fluctuations. In this active state the catalytic function results from a
self-regulating interplay of several elementary processes.Comment: 18 pages including 9 figures; related publications can be found at
http://www.fhi-berlin.mpg.de/th/th.htm
Public preferences on written informed consent for low-risk pragmatic clinical trials in Spain
Aims: Pragmatic randomized clinical trials (pRCTs) collect data that have the potential to improve medical care significantly. However, these trials may be undermined by the requirement to obtain written informed consent, which can decrease accrual and increase selection bias. Recent data suggest that the majority of the US public endorses written consent for low-risk pRCTs. The present study was designed to assess whether this view is specific to the US. Methods: The study took the form of a cross-sectional, probability-based survey, with a 2 × 2 factorial design, assessing support for written informed consent vs. verbal consent or general notification for two low-risk pRCTs in hypertension, one comparing two drugs with similar risk/benefit profiles and the other comparing the same drug being taken in the morning or at night. The primary outcome measures were respondents' personal preference and hypothetical recommendation to a research ethics committee regarding the use of written informed consent vs. the alternatives. Results: A total of 2008 adults sampled from a probability-based online panel responded to the web-based survey conducted in May 2016 (response rate: 61%). Overall, 77% of respondents endorsed written consent. In both scenarios, the alternative of general notification received significantly more support (28.7–37.1%) than the alternative of verbal consent (12.7–14.0%) (P = 0.001). Forty per cent of respondents preferred and/or recommended general notification rather than written consent. Conclusions: The results suggested that, rather than attempting to waive written consent, current pRCTs should focus on developing ways to implement written consent that provide sufficient information without undermining recruitment or increasing selection bias. The finding that around 40% of respondents endorsed general notification over written consent raises the possibility that, with educational efforts, the majority of Spaniards might accept general notification for low-risk pRCTsThis work was supported in part by the Victor Grifols i Lucas Foundation (Barcelona, Spain:http://www.fundaciogrifols.org/en/web/fundacio/home). The present work was funded in part by intramural research funds of the US NIH Clinical Cente
Ice loads acting on a model podded propeller blade (OMAE2005-67416)
With the increase in popularity of podded propulsors and arctic navigation, understanding the interaction between a podded propulsor and ice has become more important. Propeller-ice interaction itself is a complicated process with a high level of uncertainty resulting from the uncertainties associated with the properties of the ice and with the propeller-ice interaction conditions. Model tests provide relatively well-controlled ice properties and interaction conditions to reduce the uncertainties. In order to improve the understanding of this interaction and to develop numerical models of it, a model podded propulsor was used in “Puller” mode, and ice loads were measured on its instrumented blade and propeller shaft. The results of the experiments conducted to simulate the interactions (milling) of the instrumented blade with ice in different operating conditions are reported in this paper. Loads measured during the milling consist of ice milling loads, “inseparable” hydrodynamic loads, and “separable” hydrodynamic loads. The sample results presented here include ice milling and inseparable hydrodynamic loads for various advance coefficients and depths of cut (amount of blade penetration into ice). Some results are compared with existing ice load models
KIAA1114, a full-length protein encoded by the trophinin gene, is a novel surface marker for isolating tumor-initiating cells of multiple hepatocellular carcinoma subtypes
Identification of novel biomarkers for tumor-initiating cells (TICs) is of critical importance for developing diagnostic and therapeutic strategies against cancers. Here we identified the role of KIAA1114, a full-length translational product of the trophinin gene, as a distinctive marker for TICs in human liver cancer by developing a DNA vaccine-induced monoclonal antibody targeting the putative extracellular domain of KIAA1114. Compared with other established markers of liver TICs, KIAA1114 was unique in that its expression was detected in both alpha fetoprotein (AFP)-positive and AFP-negative hepatocellular carcinoma (HCC) cell lines with the expression levels of KIAA1114 being positively correlated to their tumorigenic potentials. Notably, KIAA1114 expression was strongly detected in primary hepatic tumor, but neither in the adjacent non-tumorous tissue from the same patient nor normal liver tissue. KIAA1114(high) cells isolated from HCC cell lines displayed TIC-like features with superior functional and phenotypic traits compared to their KIAA1114(low) counterparts, including tumorigenic abilities in xenotransplantation model, in vitro colony- and spheroid-forming capabilities, expression of stemness-associated genes, and migratory capacity. Our findings not only address the value of a novel antigen, KIAA1114, as a potential diagnostic factor of human liver cancer, but also as an independent biomarker for identifying TIC populations that could be broadly applied to the heterogeneous HCC subtypes.X1110Nsciescopu
High performance liquid chromatography method development and chemometric analysis of ecstasy and cocaine
Consumption of illegal drugs of abuse remains a major social issue aligned with a \ud
global law-enforcement priority. Forensic analysts are faced with the challenge of \ud
continually developing sophisticated methods of analysis to combat the increasing \ud
variability that occurs in illicit drug samples. Research work for this thesis has \ud
focused on the development of High Performance Liquid Chromatography (HPLC) \ud
methods for the analysis of major drug constituents associated with ecstasy and \ud
cocaine illicit drug samples. Emphasis has been placed on method development with \ud
strategies of univariate or multivariate experimental approaches used in the selection \ud
and optimisation of procedures. Considerations with regard to the choice of \ud
chromatographic factors, solutes under investigation and the provision of quality \ud
assurance data throughout the research work have been the main criteria in methods \ud
developed. Two HPLC methods were developed to qualitatively and quantitatively \ud
assay for the major drug components and analogue derivatives found in ecstasy and \ud
cocaine. Methods developed have undergone validation studies including intra- and \ud
inter- reproducibility, accuracy, and linearity of calibration, limit of detection (LOD) \ud
and limit of quantification (LOQ) and the use of internal standards. Applications of \ud
methods to ecstasy and cocaine samples seized in Ireland ensured their suitability for \ud
routine analysis of illicit drug samples.\ud
As part of this study, chemical profiling of 183 ecstasy tablets seized in Ireland during \ud
2002-2004 were recorded as discrete data sets. Chemical data sets include both the \ud
quantification and occurrence in individual tablets of the major amphetamine \ud
components (i.e. MDA, MDMA, MDEA, MBDB methamphetamine and \ud
amphetamine), adulterant components (i.e. caffeine, phenacetin, acetaminophen and \ud
acetylsalicylic acid), excipients components (i.e. sucrose, glucose, lactose, fructose, \ud
mannitol, sorbitol and inositol) and inorganic components (i.e. Al, Zn, Fe, Mg, Ca, Cr, \ud
Pb, Na and K ). Chemometrics, including unsupervised methods of principal \ud
component analysis (PCA), hierarchical cluster analysis (HCA) and Pearson’s \ud
correlation coefficient, as well as supervised methods of linear discriminant analysis \ud
(LDA) and artificial neural networks (ANN) was applied to the chemical data sets to \ud
demonstrate the ability of the statistical approach to linking sample seizures. HCA \ud
and ANN were the numerical methods that most efficiently distinguished between\ud
5HPLC method development & chemometric analysis of ecstasy & cocaine\ud
linked and unlinked seizures. Eleven groups were identified from the chemical data \ud
sets with group classification dependant on the main amphetamine, adulterant and \ud
excipient components present. The benefits from this study can provide strategic \ud
intelligence and an understanding of the operational level on the Irish ecstasy market \ud
and help evaluate the changing profile or dynamics associated with this illegal market \ud
supply
The Gauging of Five-dimensional, N=2 Maxwell-Einstein Supergravity Theories coupled to Tensor Multiplets
We study the general gaugings of N=2 Maxwell-Einstein supergravity theories
(MESGT) in five dimensions, extending and generalizing previous work. The
global symmetries of these theories are of the form SU(2)_R X G, where SU(2)_R
is the R-symmetry group of the N=2 Poincare superalgebra and G is the group of
isometries of the scalar manifold that extend to symmetries of the full action.
We first gauge a subgroup K of G by turning some of the vector fields into
gauge fields of K while dualizing the remaining vector fields into tensor
fields transforming in a non-trivial representation of K. Surprisingly, we find
that the presence of tensor fields transforming non-trivially under the
Yang-Mills gauge group leads to the introduction of a potential which does not
admit an AdS ground state. Next we give the simultaneous gauging of the U(1)_R
subgroup of SU(2)_R and a subgroup K of G in the presence of K-charged tensor
multiplets. The potential introduced by the simultaneous gauging is the sum of
the potentials introduced by gauging K and U(1)_R separately. We present a list
of possible gauge groups K and the corresponding representations of tensor
fields. For the exceptional supergravity we find that one can gauge the SO^*(6)
subgroup of the isometry group E_{6(-26)} of the scalar manifold if one
dualizes 12 of the vector fields to tensor fields just as in the gauged N=8
supergravity.Comment: Latex file, 23 page
- …