912 research outputs found
Chronic pain detection from resting-state raw EEG signals using improved feature selection
We present an automatic approach that works on resting-state raw EEG data for
chronic pain detection. A new feature selection algorithm - modified Sequential
Floating Forward Selection (mSFFS) - is proposed. The improved feature
selection scheme is rather compact but displays better class separability as
indicated by the Bhattacharyya distance measures and better visualization
results. It also outperforms selections generated by other benchmark methods,
boosting the test accuracy to 97.5% and yielding a test accuracy of 81.4% on an
external dataset that contains different types of chronic painComment: 9 pages, 4 figures, journal submissio
Characterisation of red-giant stars in the public Kepler data
The first public release of long-cadence stellar photometric data collected
by the NASA Kepler mission has now been made available. In this paper we
characterise the red-giant (G-K) stars in this large sample in terms of their
solar-like oscillations. We use published methods and well-known scaling
relations in the analysis. Just over 70% of the red giants in the sample show
detectable solar-like oscillations, and from these oscillations we are able to
estimate the fundamental properties of the stars. This asteroseismic analysis
reveals different populations: low-luminosity H-shell burning red-giant branch
stars, cool high-luminosity red giants on the red-giant branch and He-core
burning clump and secondary-clump giants.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical
Society Main Journa
Olfactomedin 4 Serves as a Marker for Disease Severity in Pediatric Respiratory Syncytial Virus (RSV) Infection
Funding: Statement of financial support: The study was financially supported by the VIRGO consortium, an Innovative Cluster approved by the Netherlands Genomics Initiative and partially funded by the Dutch Government (BSIK 03012). The authors have indicated they have no personal financial relationships relevant to this article to disclose. Data Availability Statement: The data is accessible at http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE69606.Peer reviewedPublisher PD
Characteristics of solar-like oscillations of secondary red clump stars
We calculated the populations of core-helium-burning (CHeB) stars and found
that the secondary red clump (SRC) stars can form an SRC peak in the
distributions of the frequency of maximum seismic amplitude () and
mean large-frequency separation () of CHeB stars when metallicity 0.02. The and of CHeB stars are dependent not
only on He core mass but on H-shell burning. The SRC peak is composed of the
CHeB stars with mass roughly between the critical mass M_{Hef} and M_{Hef}+0.2
while He core mass is between about 0.33 and 0.36 M_{sun}. The location of the
SRC peak can be affected by the mixing-length parameter , metallicity
, and overshooting parameter . A decrease in or
increase in or leads to a movement of the SRC peak towards a
lower frequency. However, the change in and only slightly affects
the value of M_{Hef} but the variation in can significantly
affects the value of M_{Hef}. Thus the SRC peak might aid in determining the
value of M_{Hef} and calibrating . In addition, the effects of
convective acceleration of SRC stars and the of `semi-degenerate'
stars decreasing with mass result in the appearance of a shoulder between about
40 and 50 hz in the \dnu{} distribution. However, the convective
acceleration of stars with M < M_{Hef} leads to the deficit in the
distribution between about 9 and 20 hz{}. Moreover, the value of the
parameter of the relation between and for the
populations with M > M_{Hef} is obviously larger than that for the populations
with \dmhef{}.Comment: 10 pages, 15 figures. Accepted for publication in MNRA
Introductory clifford analysis
In this chapter an introduction is given to Clifford analysis and the underlying Clifford algebras. The functions under consideration are defined on Euclidean space and take values in the universal real or complex Clifford algebra, the structure and properties of which are also recalled in detail. The function theory is centered around the notion of a monogenic function, which is a null solution of a generalized CauchyâRiemann operator, which is rotation invariant and factorizes the Laplace operator. In this way, Clifford analysis may be considered as both a generalization to higher dimension of the theory of holomorphic functions in the complex plane and a refinement of classical harmonic analysis. A notion of monogenicity may also be associated with the vectorial part of the CauchyâRiemann operator, which is called the Dirac operator; some attention is paid to the intimate relation between both notions. Since a product of monogenic functions is, in general, no longer monogenic, it is crucial to possess some tools for generating monogenic functions: such tools are provided by Fueterâs theorem on one hand and the CauchyâKovalevskaya extension theorem on the other hand. A corner stone in this function theory is the Cauchy integral formula for representation of a monogenic function in the interior of its domain of monogenicity. Starting from this representation formula and related integral formulae, it is possible to consider integral transforms such as Cauchy, Hilbert, and Radon transforms, which are important both within the theoretical framework and in view of possible applications
Convection and oscillations
In this short review on stellar convection dynamics I address the following,
currently very topical, issues: (1) the surface effects of the Reynolds
stresses and nonadiabaticity on solar-like pulsation frequencies, and (2)
oscillation mode lifetimes of stochastically excited oscillations in red giants
computed with different time-dependent convection formulations.Comment: Accepted for publication in Astronomische Nachrichten, HELA IV
proceedings, T. Roca Cort\'es, P. Pall\'e, S. Jim\'enez Reyes, eds, 7 figure
Spin down of the core rotation in red giants
The space mission Kepler provides us with long and uninterrupted photometric
time series of red giants. We are now able to probe the rotational behaviour in
their deep interiors using the observations of mixed modes. We aim to measure
the rotational splittings in red giants and to derive scaling relations for
rotation related to seismic and fundamental stellar parameters. We have
developed a dedicated method for automated measurements of the rotational
splittings in a large number of red giants. Ensemble asteroseismology, namely
the examination of a large number of red giants at different stages of their
evolution, allows us to derive global information on stellar evolution. We have
measured rotational splittings in a sample of about 300 red giants. We have
also shown that these splittings are dominated by the core rotation. Under the
assumption that a linear analysis can provide the rotational splitting, we
observe a small increase of the core rotation of stars ascending the red giant
branch. Alternatively, an important slow down is observed for red-clump stars
compared to the red giant branch. We also show that, at fixed stellar radius,
the specific angular momentum increases with increasing stellar mass. Ensemble
asteroseismology indicates what has been indirectly suspected for a while: our
interpretation of the observed rotational splittings leads to the conclusion
that the mean core rotation significantly slows down during the red giant
phase. The slow-down occurs in the last stages of the red giant branch. This
spinning down explains, for instance, the long rotation periods measured in
white dwarfsComment: Accepted in A&
Measuring and understanding photo sharing experiences in social virtual reality
Millions of photos are shared online daily, but the richness of interaction compared with face-to-face (F2F) sharing is still missing. While this may change with social Virtual Reality (socialVR), we still lack tools to measure such immersive and interactive experiences. In this paper, we investigate photo sharing experiences in immersive environments, focusing on socialVR. Running context mapping (N=10), an expert creative session (N=6), and an online experience clustering questionnaire (N=20), we develop and statistically evaluate a questionnaire to measure photo sharing experiences. We then ran a controlled, within-subject study (N=26 pairs) to compare photo sharing under F2F, Skype, and Facebook Spaces. Using interviews, audio analysis, and our questionnaire, we found that socialVR can closely approximate F2F sharing. We contribute empirical findings on the immersiveness differences between digital communication media, and propose a socialVR questionnaire that can in the future generalize beyond photo sharing
Serum Immune Profiling in Paediatric Crohn's Disease Demonstrates Stronger Immune Modulation With First-Line Infliximab Than Conventional Therapy and Pre-Treatment Profiles Predict Clinical Response to Both Treatments
BACKGROUND: Despite its efficacy, rational guidance for starting/stopping first-line biologic treatment in individual paediatric Crohn's disease [CD] patients is needed. We assessed how serum immune profiles before and after first-line infliximab [FL-IFX] or conventional [CONV] induction therapy associate with disease remission at week 52. METHODS: Pre- [nâ
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86], and 10-14-week post-treatment [nâ
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84] sera were collected from patients with moderate-to-severe paediatric CD in the TISKids trial, randomized to FL-IFX [nâ
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48; five 5-mg/kg infusions over 22 weeks] or CONV [nâ
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43; exclusive enteral nutrition or oral prednisolone]; both groups received azathioprine maintenance. The relative concentrations of 92 inflammatory proteins were determined with Olink Proteomics; fold changes [FC] with |log2FC| > 0.5 after false discovery rate adjustment were considered significant. RESULTS: FL-IFX modulated a larger number of inflammatory proteins and induced stronger suppression than CONV; 18/30 proteins modulated by FL-IFX were not regulated by CONV. Hierarchical clustering based on IFX-modulated proteins at baseline revealed two clusters of patients: CD-hi patients had significantly higher concentrations of 23/30 IFX-modulated proteins [including oncostatin-M, TNFSF14, HGF and TGF-α], and higher clinical disease activity, C-reactive protein and blood neutrophils at baseline than CD-lo patients. Only 24% of CD-hi FL-IFX-treated patients maintained remission without escalation at week 52 vs 58% of CD-lo FL-IFX-treated patients. Similarly, 6% of CD-hi CONV-treated patients achieved remission vs 20% of CONV-treated CD-lo patients. Clustering based on immune profiles post-induction therapy did not relate to remission at week 52. CONCLUSION: FL-IFX leads to stronger reductions and modulates more immune proteins than CONV. Stratification on pre-treatment profiles of IFX-modulated proteins directly relates to maintenance of remission without treatment escalation. TRIAL REGISTRATION NUMBER: NCT02517684.</p
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