694 research outputs found
The performance of socially responsible mutual funds: the role of fees and management companies
In this paper, we shed light on the debate about the financial performance of socially responsible investment (SRI) mutual funds by separately analyzing the contributions of before-fee performance and fees to SRI funds' performance and by investigating the role played by fund management companies in the determination of those variables. We apply the matching estimator methodology to obtain our results and find that in the period 1997-2005, US SRI funds had significantly higher fees and better before- and after-fee performance than conventional funds with similar characteristics. Differences, however, were driven exclusively by SRI funds run by management companies specialized in socially responsible investment.Socially responsible investment, Mutual fund fees, Mutual fund performance, Matching estimators
Dynamical replica theoretic analysis of CDMA detection dynamics
We investigate the detection dynamics of the Gibbs sampler for code-division
multiple access (CDMA) multiuser detection. Our approach is based upon
dynamical replica theory which allows an analytic approximation to the
dynamics. We use this tool to investigate the basins of attraction when phase
coexistence occurs and examine its efficacy via comparison with Monte Carlo
simulations.Comment: 18 pages, 2 figure
Application of Deep Learning Long Short-Term Memory in Energy Demand Forecasting
The smart metering infrastructure has changed how electricity is measured in
both residential and industrial application. The large amount of data collected
by smart meter per day provides a huge potential for analytics to support the
operation of a smart grid, an example of which is energy demand forecasting.
Short term energy forecasting can be used by utilities to assess if any
forecasted peak energy demand would have an adverse effect on the power system
transmission and distribution infrastructure. It can also help in load
scheduling and demand side management. Many techniques have been proposed to
forecast time series including Support Vector Machine, Artificial Neural
Network and Deep Learning. In this work we use Long Short Term Memory
architecture to forecast 3-day ahead energy demand across each month in the
year. The results show that 3-day ahead demand can be accurately forecasted
with a Mean Absolute Percentage Error of 3.15%. In addition to that, the paper
proposes way to quantify the time as a feature to be used in the training phase
which is shown to affect the network performance
Probabilistic Reconstruction in Compressed Sensing: Algorithms, Phase Diagrams, and Threshold Achieving Matrices
Compressed sensing is a signal processing method that acquires data directly
in a compressed form. This allows one to make less measurements than what was
considered necessary to record a signal, enabling faster or more precise
measurement protocols in a wide range of applications. Using an
interdisciplinary approach, we have recently proposed in [arXiv:1109.4424] a
strategy that allows compressed sensing to be performed at acquisition rates
approaching to the theoretical optimal limits. In this paper, we give a more
thorough presentation of our approach, and introduce many new results. We
present the probabilistic approach to reconstruction and discuss its optimality
and robustness. We detail the derivation of the message passing algorithm for
reconstruction and expectation max- imization learning of signal-model
parameters. We further develop the asymptotic analysis of the corresponding
phase diagrams with and without measurement noise, for different distribution
of signals, and discuss the best possible reconstruction performances
regardless of the algorithm. We also present new efficient seeding matrices,
test them on synthetic data and analyze their performance asymptotically.Comment: 42 pages, 37 figures, 3 appendixe
FAK acts as a suppressor of RTK-MAP kinase signalling in Drosophila melanogaster epithelia and human cancer cells
Receptor Tyrosine Kinases (RTKs) and Focal Adhesion Kinase (FAK) regulate multiple signalling pathways, including mitogen-activated protein (MAP) kinase pathway. FAK interacts with several RTKs but little is known about how FAK regulates their downstream signalling. Here we investigated how FAK regulates signalling resulting from the overexpression of the RTKs RET and EGFR. FAK suppressed RTKs signalling in Drosophila melanogaster epithelia by impairing MAPK pathway. This regulation was also observed in MDA-MB-231 human breast cancer cells, suggesting it is a conserved phenomenon in humans. Mechanistically, FAK reduced receptor recycling into the plasma membrane, which resulted in lower MAPK activation. Conversely, increasing the membrane pool of the receptor increased MAPK pathway signalling. FAK is widely considered as a therapeutic target in cancer biology; however, it also has tumour suppressor properties in some contexts. Therefore, the FAK-mediated negative regulation of RTK/MAPK signalling described here may have potential implications in the designing of therapy strategies for RTK-driven tumours
Radio-frequency dressed state potentials for neutral atoms
Potentials for atoms can be created by external fields acting on properties
like magnetic moment, charge, polarizability, or by oscillating fields which
couple internal states. The most prominent realization of the latter is the
optical dipole potential formed by coupling ground and electronically excited
states of an atom with light. Here we present an experimental investigation of
the remarkable properties of potentials derived from radio-frequency (RF)
coupling between electronic ground states. The coupling is magnetic and the
vector character allows to design state dependent potential landscapes. On atom
chips this enables robust coherent atom manipulation on much smaller spatial
scales than possible with static fields alone. We find no additional heating or
collisional loss up to densities approaching atoms / cm compared
to static magnetic traps. We demonstrate the creation of Bose-Einstein
condensates in RF potentials and investigate the difference in the interference
between two independently created and two coherently split condensates in
identical traps. All together this makes RF dressing a powerful new tool for
micro manipulation of atomic and molecular systems
Triclinic modification of N-[(1,1-dimethylethoxy)carbonyl]-3-[(R)-prop-2-en-1-ylsulfinyl]-(R)-alanine ethyl ester at 120 (1) K
There are two independent molecules in the asymmetric unit of the title compound, C13H23NO5S. In the crystal structure, intermolecular N—H⋯O hydrogen bonds link molecules into two independent one-dimensional chains along [100]. The crystal studied was found to be a non-merohedral twin with a ratio of 0.615 (6):0.385 (1) for the refined components. At 200 (1) K [Singh et al. (2009 ▶). Acta Cryst. E65, o1385–o1386] the crystal structure of the title compound contains one disordered molecule in the asymmetric unit of a monoclinic unit cell
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
Model-based analysis of photoinitiated coating degradation under artificial exposure conditions
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