pinecone/core-2020-05-10-deduplication huggingface dataset:
Deep learning for detecting freezing of gait episodes in Parkinson’s disease based on accelerometers

The final publication is available at Springer via https://doi.org/10.1007/978-3-319-59147-6_30Freezing of gait (FOG) is one of the most incapacitating symptoms among the motor alterations of Parkinson’s disease (PD). Manifesting FOG episodes reduce patients’ quality of life and their autonomy to perform daily living activities, while it may provoke falls. Accurate ambulatory FOG assessment would enable non-pharmacologic support based on cues and would provide relevant information to neurologists on the disease evolution.\ud
\ud
This paper presents a method for FOG detection based on deep learning and signal processing techniques. This is, to the best of our knowledge, the first time that FOG detection is addressed with deep learning. The evaluation of the model has been done based on the data from 15 PD patients who manifested FOG. An inertial measurement unit placed at the left side of the waist recorded tri-axial accelerometer, gyroscope and magnetometer signals. Our approach achieved comparable results to the state-of-the-art, reaching validation performances of 88.6% and 78% for sensitivity and specificity respectively.Peer ReviewedPostprint (author's final draft
Deep Learning to Analyze RNA-Seq Gene Expression Data

Deep learning models are currently being applied in several
areas with great success. However, their application for the analysis of high-throughput sequencing data remains a challenge for the research community due to the fact that this family of models are known to work very well in big datasets with lots of samples available, just the opposite scenario typically found in biomedical areas. In this work, a first approximation on the use of deep learning for the analysis of RNA-Seq gene expression profiles data is provided. Three public cancer-related databases are analyzed using a regularized linear model (standard LASSO) as baseline model, and two deep learning models that differ on the feature selection technique used prior to the application of a deep neural net model. The results indicate that a straightforward application of deep nets implementations available in public scientific tools and under the conditions described within this work is not enough to outperform simpler models like LASSO. Therefore, smarter and more complex ways that incorporate prior biological knowledge into the estimation procedure of deep learning models may be necessary in order to obtain better results in terms of predictive performance.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Verifying Integer Programming Results

Software for mixed-integer linear programming can return incorrect results
for a number of reasons, one being the use of inexact floating-point
arithmetic. Even solvers that employ exact arithmetic may suffer from
programming or algorithmic errors, motivating the desire for a way to produce
independently verifiable certificates of claimed results. Due to the complex
nature of state-of-the-art MILP solution algorithms, the ideal form of such a
certificate is not entirely clear. This paper proposes such a certificate
format, illustrating its capabilities and structure through examples. The
certificate format is designed with simplicity in mind and is composed of a
list of statements that can be sequentially verified using a limited number of
simple yet powerful inference rules. We present a supplementary verification
tool for compressing and checking these certificates independently of how they
were created. We report computational results on a selection of mixed-integer
linear programming instances from the literature. To this end, we have extended
the exact rational version of the MIP solver SCIP to produce such certificates.Comment: Zuse Institute Berlin, Takustr. 7, 14195 Berlin, November 2016,
  http://nbn-resolving.de/urn:nbn:de:0297-zib-6104
Discrete Newton’s Algorithm for Parametric Submodular Function Minimization

We consider the line search problem in a submodular polyhedron P (f) ⊆ ℝ n : Given an arbitrary a ∈ ℝ n  and x 0  ∈ P (f), compute max{δ: x 0  + δa ∈ P (f)}. The use of the discrete Newton’s algorithm for this line search problem is very natural, but no strongly polynomial bound on its number of iterations was known (Iwata 2008). We solve this open problem by providing a quadratic bound of n 2  + O(n log 2  n) on its number of iterations. Our result considerably improves upon the only other known strongly polynomial time algorithm, which is based on Megiddo’s parametric search framework and which requires Õ(n 8 ) submodular function minimizations (Nagano 2007). As a by-product of our study, we prove (tight) bounds on the length of chains of ring families and geometrically increasing sequences of sets, which might be of independent interest. Keywords:
Discrete Newton’s algorithm; Submodular functions; Line search; Ring families; Geometrically increasing sequence of sets; Fractional combinatorial optimizatio
On the notions of facets, weak facets, and extreme functions of the
  Gomory-Johnson infinite group problem

We investigate three competing notions that generalize the notion of a facet
of finite-dimensional polyhedra to the infinite-dimensional Gomory-Johnson
model. These notions were known to coincide for continuous piecewise linear
functions with rational breakpoints. We show that two of the notions, extreme
functions and facets, coincide for the case of continuous piecewise linear
functions, removing the hypothesis regarding rational breakpoints. We then
separate the three notions using discontinuous examples.Comment: 18 pages, 2 figure
What's new? Analysing language-specific Wikipedia entity contexts to support entity-centric news retrieval.

Representation of influential entities, such as celebrities and multinational corporations on the web can vary across languages, re- flecting language-specific entity aspects, as well as divergent views on these entities in different communities. An important source of multilingual background knowledge about influential entities is Wikipedia — an online community-created encyclopaedia — containing more than 280 language editions. Such language-specific information could be applied in entity-centric information retrieval applications, in which users utilise very simple queries, mostly just the entity names, for the relevant documents. In this article we focus on the problem of creating languagespecific entity contexts to support entity-centric, language-specific information retrieval applications. First, we discuss alternative ways such contexts can be built, including Graph-based and Article-based approaches. Second, we analyse the similarities and the differences in these contexts in a case study including 220 entities and five Wikipedia language editions. Third, we propose a context-based entity-centric information retrieval model that maps documents to aspect space, and apply languagespecific entity contexts to perform query expansion. Last, we perform a case study to demonstrate the impact of this model in a news retrieval application. Our study illustrates that the proposed model can effectively improve the recall of entity-centric information retrieval while keeping high precision, and provide language-specific results
Making Use of Empty Intersections to Improve the Performance of CbO-Type Algorithms

This paper describes how improvements in the performance of Close-by-One type algorithms can be achieved by making use of empty intersections in the computation of formal concepts. During the computation, if the intersection between the current concept extent and the next attribute-extent is empty, this fact can be simply inherited by subsequent children of the current concept. Thus subsequent intersections with the same attribute-extent can be skipped. Because these intersections require the testing of each object in the current extent, significant time savings can be made by avoiding them. The paper also shows how further time savings can be made by forgoing the traditional canonicity test for new extents, if the intersection is empty. Finally, the paper describes how, because of typical optimizations made in the implementation of CbO-type algorithms, even more time can be saved by amalgamating inherited attributes with inherited empty intersections into a single, simple test
On the Usability of Probably Approximately Correct Implication Bases

We revisit the notion of probably approximately correct implication bases
from the literature and present a first formulation in the language of formal
concept analysis, with the goal to investigate whether such bases represent a
suitable substitute for exact implication bases in practical use-cases. To this
end, we quantitatively examine the behavior of probably approximately correct
implication bases on artificial and real-world data sets and compare their
precision and recall with respect to their corresponding exact implication
bases. Using a small example, we also provide qualitative insight that
implications from probably approximately correct bases can still represent
meaningful knowledge from a given data set.Comment: 17 pages, 8 figures; typos added, corrected x-label on graph
Aggregating fuzzy subgroups and T-vague groups

Fuzzy subgroups and T-vague groups are interesting fuzzy algebraic structures that have been widely studied. While fuzzy subgroups fuzzify the concept of crisp subgroup, T-vague groups can be identified with quotient groups of a group by a normal fuzzy subgroup and there is a close relation between both structures and T-indistinguishability operators (fuzzy equivalence relations).\ud
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In this paper the functions that aggregate fuzzy subgroups and T-vague groups will be studied. The functions aggregating T-indistinguishability operators have been characterized [9] and the main result of this paper is that the functions aggregating T-indistinguishability operators coincide with the ones that aggregate fuzzy subgroups and T-vague groups. In particular, quasi-arithmetic means and some OWA operators aggregate them if the t-norm is continuous Archimedean.Peer ReviewedPostprint (author's final draft
Stellar evolution and modelling stars

In this chapter I give an overall description of the structure and evolution
of stars of different masses, and review the main ingredients included in
state-of-the-art calculations aiming at reproducing observational features. I
give particular emphasis to processes where large uncertainties still exist as
they have strong impact on stellar properties derived from large compilations
of tracks and isochrones, and are therefore of fundamental importance in many
fields of astrophysics.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
Deriving High-Precision Radial Velocities

This chapter describes briefly the key aspects behind the derivation of
precise radial velocities. I start by defining radial velocity precision in the
context of astrophysics in general and exoplanet searches in particular. Next I
discuss the different basic elements that constitute a spectrograph, and how
these elements and overall technical choices impact on the derived radial
velocity precision. Then I go on to discuss the different wavelength
calibration and radial velocity calculation techniques, and how these are
intimately related to the spectrograph's properties. I conclude by presenting
some interesting examples of planets detected through radial velocity, and some
of the new-generation instruments that will push the precision limit further.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
Models of radial velocities and transit light curves

Research in extrasolar-planet science is data-driven. With the advent of
radial-velocity instruments like HARPS and HARPS-N, and transit space missions
like Kepler, our ability to discover and characterise extrasolar planets is no
longer limited by instrumental precision but by our ability to model the data
accurately. This chapter presents the models that describe radial-velocity
measurements and transit light curves. I begin by deriving the solution of the
two-body problem and from there, the equations describing the radial velocity
of a planet-host star and the distance between star and planet centres,
necessary to model transit light curves. Stochastic models are then presented
and I delineate how they are used to model complex physical phenomena affecting
the exoplanet data sets, such as stellar activity. Finally, I give a brief
overview of the processes of Bayesian inference, focussing on the construction
of likelihood functions and prior probability distributions. In particular, I
describe different methods to specify ignorance priors.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
Characterization of Exoplanet-Host Stars

Precise and, if possible, accurate characterization of exoplanets cannot be
dissociated from the characterization of their host stars. In this chapter we
discuss different methods and techniques used to derive fundamental properties
and atmospheric parameters of exoplanet-host stars. The main limitations,
advantages and disadvantages, as well as corresponding typical measurement
uncertainties of each method are presented.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
Noise Sources in Photometry and Radial Velocities

The quest for Earth-like, extrasolar planets (exoplanets), especially those
located inside the habitable zone of their host stars, requires techniques
sensitive enough to detect the faint signals produced by those planets. The
radial velocity (RV) and photometric transit methods are the most widely used
and also the most efficient methods for detecting and characterizing
exoplanets. However, presence of astrophysical "noise" makes it difficult to
detect and accurately characterize exoplanets. It is important to note that the
amplitude of such astrophysical noise is larger than both the signal of
Earth-like exoplanets and state-of-the-art instrumentation limit precision,
making this a pressing topic that needs to be addressed. In this chapter, I
present a general review of the main sources of noise in photometric and RV
observations, namely, stellar oscillations, granulation, and magnetic activity.
Moreover, for each noise source I discuss the techniques and observational
strategies which allow us to mitigate their impact.Comment: 11 pages, 2 tables, Lecture presented at the IVth Azores
  International Advanced School in Space Sciences on "Asteroseismology and
  Exoplanets: Listening to the Stars and Searching for New Worlds"
  (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in
  July 201
Measuring Stellar Atmospheric Parameters with ARES+MOOG

The technical aspects in the use of an Equivalent Width (EW) method are
described for the derivation of spectroscopic stellar parameters with
ARES+MOOG. While the science description behind this method can be found in
many references, here the goal is to provide a user manual approach for the
codes and scripts presented in for the tutorial. All the required data is
available online (https://github.com/sousasag/school_codes).Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portuga
Theory of Stellar Oscillations

In recent years, astronomers have witnessed major progresses in the field of
stellar physics. This was made possible thanks to the combination of a solid
theoretical understanding of the phenomena of stellar pulsations and the
availability of a tremendous amount of exquisite space-based asteroseismic
data. In this context, this chapter reviews the basic theory of stellar
pulsations, considering small, adiabatic perturbations to a static, spherically
symmetric equilibrium. It starts with a brief discussion of the solar
oscillation spectrum, followed by the setting of the theoretical problem,
including the presentation of the equations of hydrodynamics, their
perturbation, and a discussion of the functional form of the solutions.
Emphasis is put on the physical properties of the different types of modes, in
particular acoustic (p-) and gravity (g-) modes and their propagation cavities.
The surface (f-) mode solutions are also discussed. While not attempting to be
comprehensive, it is hoped that the summary presented in this chapter addresses
the most important theoretical aspects that are required for a solid start in
stellar pulsations research.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
An Introduction to Data Analysis in Asteroseismology

A practical guide is presented to some of the main data analysis concepts and
techniques employed contemporarily in the asteroseismic study of stars
exhibiting solar-like oscillations. The subjects of digital signal processing
and spectral analysis are introduced first. These concern the acquisition of
continuous physical signals to be subsequently digitally analyzed. A number of
specific concepts and techniques relevant to asteroseismology are then
presented as we follow the typical workflow of the data analysis process,
namely, the extraction of global asteroseismic parameters and individual mode
parameters (also known as peak-bagging) from the oscillation spectrum.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
Stellar Inversion Techniques

Stellar seismic inversions have proved to be a powerful technique for probing
the internal structure of stars, and paving the way for a better understanding
of the underlying physics by revealing some of the shortcomings in current
stellar models. In this lecture, we provide an introduction to this topic by
explaining kernel-based inversion techniques. Specifically, we explain how
various kernels are obtained from the pulsation equations, and describe
inversion techniques such as the Regularised Least-Squares (RLS) and Optimally
Localised Averages (OLA) methods.Comment: 20 pages, 8 figures. Lecture presented at the IVth Azores
  International Advanced School in Space Sciences on "Asteroseismology and
  Exoplanets: Listening to the Stars and Searching for New Worlds"
  (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in
  July 201
Asteroseismology of red giants & galactic archaeology

Red-giant stars are low- to intermediate-mass ($M \lesssim 10$~M$_{\odot}$)
stars that have exhausted hydrogen in the core. These extended, cool and hence
red stars are key targets for stellar evolution studies as well as galactic
studies for several reasons: a) many stars go through a red-giant phase; b) red
giants are intrinsically bright; c) large stellar internal structure changes as
well as changes in surface chemical abundances take place over relatively short
time; d) red-giant stars exhibit global intrinsic oscillations. Due to their
large number and intrinsic brightness it is possible to observe many of these
stars up to large distances. Furthermore, the global intrinsic oscillations
provide a means to discern red-giant stars in the pre-helium core burning from
the ones in the helium core burning phase and provide an estimate of stellar
ages, a key ingredient for galactic studies. In this lecture I will first
discuss some physical phenomena that play a role in red-giant stars and several
phases of red-giant evolution. Then, I will provide some details about
asteroseismology -- the study of the internal structure of stars through their
intrinsic oscillations -- of red-giant stars. I will conclude by discussing
galactic archaeology -- the study of the formation and evolution of the Milky
Way by reconstructing its past from its current constituents -- and the role
red-giant stars can play in that.Comment: Lecture presented at the IVth Azores International Advanced School in
  Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
  and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
  Azores Islands, Portugal in July 201
Synergies between Asteroseismology and Exoplanetary Science

Over the past decade asteroseismology has become a powerful method to
systematically characterize host stars and dynamical architectures of exoplanet
systems. In this contribution I review current key synergies between
asteroseismology and exoplanetary science such as the precise determination of
planet radii and ages, the measurement of orbital eccentricities, stellar
obliquities and their impact on hot Jupiter formation theories, and the
importance of asteroseismology on spectroscopic analyses of exoplanet hosts. I
also give an outlook on future synergies such as the characterization of
sub-Neptune-size planets orbiting solar-type stars, the study of planet
populations orbiting evolved stars, and the determination of ages of
intermediate-mass stars hosting directly imaged planets.Comment: 18 pages, 11 figures; Lecture presented at the IVth Azores
  International Advanced School in Space Sciences on "Asteroseismology and
  Exoplanets: Listening to the Stars and Searching for New Worlds"
  (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in
  July 201