524 research outputs found
Inclusive Growth – an Agenda for Germany Five action areas for a new growth strategy. Bertelsmann Stiftung Inclusive Growth for Germany|20
Germany is entering a new legislative period with a strong
economic position. Across the board, current figures and
forecasts for the near future are encouraging. But both the
private sector and society are confronted with major challenges
– globalization, digitalization and demographic
shifts are transforming the demands made on our economy.
Current economic policy in Germany must pave the way for
tomorrow’s prosperity. This involves making a priority out
of promoting growth that provides everyone an opportunity
to participate in and thereby benefit from this growth. We
need an Agenda for Inclusive Growth
Convolutional Neural Networks for Epileptic Seizure Prediction
Epilepsy is the most common neurological disorder and an accurate forecast of
seizures would help to overcome the patient's uncertainty and helplessness. In
this contribution, we present and discuss a novel methodology for the
classification of intracranial electroencephalography (iEEG) for seizure
prediction. Contrary to previous approaches, we categorically refrain from an
extraction of hand-crafted features and use a convolutional neural network
(CNN) topology instead for both the determination of suitable signal
characteristics and the binary classification of preictal and interictal
segments. Three different models have been evaluated on public datasets with
long-term recordings from four dogs and three patients. Overall, our findings
demonstrate the general applicability. In this work we discuss the strengths
and limitations of our methodology.Comment: accepted for MLESP 201
Mass growth and mergers: direct observations of the luminosity function of LRG satellite galaxies out to z=0.7 from SDSS and BOSS images
We present a statistical study of the luminosity functions of galaxies
surrounding luminous red galaxies (LRGs) at average redshifts =0.34 and
=0.65. The luminosity functions are derived by extracting source photometry
around more than 40,000 LRGs and subtracting foreground and background
contamination using randomly selected control fields. We show that at both
studied redshifts the average luminosity functions of the LRGs and their
satellite galaxies are poorly fitted by a Schechter function due to a
luminosity gap between the centrals and their most luminous satellites. We
utilize a two-component fit of a Schechter function plus a log-normal
distribution to demonstrate that LRGs are typically brighter than their most
luminous satellite by roughly 1.3 magnitudes. This luminosity gap implies that
interactions within LRG environments are typically restricted to minor mergers
with mass ratios of 1:4 or lower. The luminosity functions further imply that
roughly 35% of the mass in the environment is locked in the LRG itself,
supporting the idea that mass growth through major mergers within the
environment is unlikely. Lastly, we show that the luminosity gap may be at
least partially explained by the selection of LRGs as the gap can be reproduced
by sparsely sampling a Schechter function. In that case LRGs may represent only
a small fraction of central galaxies in similar mass halos.Comment: ApJ accepted versio
Towards improved design and evaluation of epileptic seizure predictors
Abstract—Objective: Key issues in the epilepsy seizure prediction research are (1) the reproducibility of results (2) the
inability to compare multiple approaches directly. To overcome these problems, the Seizure Prediction Challenge was organized on Kaggle.com. It aimed at establishing benchmarks on a dataset with predefined train, validation and test sets. Our main objective is to analyse the competition format, and to propose improvements, which would facilitate a better comparison of algorithms. The second objective is to present a novel deep learning approach to seizure prediction and compare it to other commonly used methods using patient centered metrics. Methods: We used the competition’s datasets to illustrate the effects of data contamination. Having better data partitions, we compared three types of models in terms of different objectives. Results: We found that correct selection of test samples is crucial when evaluating
the performance of seizure forecasting models. Moreover, we showed that models, which achieve state-of-the-art performance with respect to commonly used AUC, sensitivity and specificity metrics, may not yet be suitable for practical usage because of low precision scores. Conclusion: Correlation between validation and test datasets used in the competition limited its scientific value. Significance: Our findings provide guidelines which allow for a more objective evaluation of seizure prediction models
Elution study of acrylic monomers from orthodontic materials using high performance liquid chromatography (HPLC)
Purpose: Main goal of the study was the identification and quantitative analysis of monomer elution from materials commonly used in fixed orthodontic therapy. Studies have shown severe health effects of monomers including cytotoxic, allergenic or mutagenic potential and endocrine changes. This in vitro study focusses primarily on five resins which are usually processed intraorally and remain in the oral cavity long-term.
Methods: We tested the elution of monomers from specimens (7.5 mm x 1.5 mm) immersed in artificial saliva at body temperature (37 degrees C) for 30 min to 5 weeks. The used method is in accordance with DIN EN ISO 10993-13. The five tested materials were BrackFix (R) (Voco GmbH, Cuxhaven, Germany), Triad (R) Gel (DeguDent GmbH, Hanau, Germany), and Transbond (TM) XT, LR and Plus (3M Unitek, Monrovia, CA, USA). All aliquots were analyzed using high performance liquid chromatography (HPLC). Data were statistically analyzed.
Results: All five analyzed materials eluted substances over a period of 5 weeks. Identified substances included bisphenol A (BPA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA). BPA eluted from Transbond (TM) Plus, XT, LR and BrackFix (R). The cumulated mean values after 35 days ranged from 16.04 to 64.83 ppm, depending on the material. TEGDMA eluted with a mean of 688.61 ppm from Transbond (TM) LR. UDMA with a mean of 1682.00 ppm from Triad (R) Gel. For each material the highest concentrations of all these substances were found in the first elution period. Other substances that were not equivocally identified or of low concentration also eluted.
Conclusion: Using the described method, it is possible to qualitatively and quantitatively determine the in vitro elution of monomers from orthodontic materials. The concentrations of the substances identified were below the current maximum recommended intake. However, a cumulative effect and low-dose effects should be considered for both patients and dental professionals, especially for young patients. Measures to reduce exposure patients and practitioners are suggested
Characterizing unknown systematics in large scale structure surveys
Photometric large scale structure (LSS) surveys probe the largest volumes in
the Universe, but are inevitably limited by systematic uncertainties. Imperfect
photometric calibration leads to biases in our measurements of the density
fields of LSS tracers such as galaxies and quasars, and as a result in
cosmological parameter estimation. Earlier studies have proposed using
cross-correlations between different redshift slices or cross-correlations
between different surveys to reduce the effects of such systematics. In this
paper we develop a method to characterize unknown systematics. We demonstrate
that while we do not have sufficient information to correct for unknown
systematics in the data, we can obtain an estimate of their magnitude. We
define a parameter to estimate contamination from unknown systematics using
cross-correlations between different redshift slices and propose discarding
bins in the angular power spectrum that lie outside a certain contamination
tolerance level. We show that this method improves estimates of the bias using
simulated data and further apply it to photometric luminous red galaxies in the
Sloan Digital Sky Survey as a case study.Comment: 24 pages, 6 figures; Expanded discussion of results, added figure 2;
Version to be published in JCA
Nanoscale Imaging Reveals a Tetraspanin-CD9 Coordinated Elevation of Endothelial ICAM-1 Clusters
Endothelial barriers have a central role in inflammation as they allow or deny the passage of leukocytes from the vasculature into the tissue. To bind leukocytes, endothelial cells form adhesive clusters containing tetraspanins and ICAM-1, so-called endothelial adhesive platforms (EAPs). Upon leukocyte binding, EAPs evolve into docking structures that emanate from the endothelial surface while engulfing the leukocyte. Here, we show that TNF-α is sufficient to induce apical protrusions in the absence of leukocytes. Using advanced quantitation of atomic force microscopy (AFM) recordings, we found these structures to protrude by 160 ± 80 nm above endothelial surface level. Confocal immunofluorescence microscopy proved them positive for ICAM-1, JAM-A, tetraspanin CD9 and f-actin. Microvilli formation was inhibited in the absence of CD9. Our findings indicate that stimulation with TNF-α induces nanoscale changes in endothelial surface architecture and that—via a tetraspanin CD9 depending mechanism—the EAPs rise above the surface to facilitate leukocyte capture
Photometric Redshift Probability Distributions for Galaxies in the SDSS DR8
We present redshift probability distributions for galaxies in the SDSS DR8
imaging data. We used the nearest-neighbor weighting algorithm presented in
Lima et al. 2008 and Cunha et al. 2009 to derive the ensemble redshift
distribution N(z), and individual redshift probability distributions P(z) for
galaxies with r < 21.8. As part of this technique, we calculated weights for a
set of training galaxies with known redshifts such that their density
distribution in five dimensional color-magnitude space was proportional to that
of the photometry-only sample, producing a nearly fair sample in that space. We
then estimated the ensemble N(z) of the photometric sample by constructing a
weighted histogram of the training set redshifts. We derived P(z) s for
individual objects using the same technique, but limiting to training set
objects from the local color-magnitude space around each photometric object.
Using the P(z) for each galaxy, rather than an ensemble N(z), can reduce the
statistical error in measurements that depend on the redshifts of individual
galaxies. The spectroscopic training sample is substantially larger than that
used for the DR7 release, and the newly added PRIMUS catalog is now the most
important training set used in this analysis by a wide margin. We expect the
primary source of error in the N(z) reconstruction is sample variance: the
training sets are drawn from relatively small volumes of space. Using
simulations we estimated the uncertainty in N(z) at a given redshift is 10-15%.
The uncertainty on calculations incorporating N(z) or P(z) depends on how they
are used; we discuss the case of weak lensing measurements. The P(z) catalog is
publicly available from the SDSS website.Comment: 29 pages, 9 figures, single colum
РОЗВИТОК СИСТЕМИ ПОЧАТКОВОЇ ТА СЕРЕДНЬОЇ ОСВІТИ У МЕНОНІТСЬКИХ КОЛОНІЯХ КАТЕРИНОСЛАВСЬКОГО ПОВІТУ НАПРИКІНЦІ XIX – НА ПОЧАТКУ XX СТ.
Проблеми формування системи початкової освіти постійно знаходи-лись у фокусі громадської уваги менонітського соціуму, який намагався шля-хом надзвичайної концентрації інтелектуальних, фінансових та господарчих зусиль сприяти її всебічному становленню та розвитку. Ґенеза менонітсько-го віровчення, темпи та масштаб його поширення серед населення північ-них регіонів Західної Європи були об'єктивно зумовлені наявністю у пред-ставників даного релігійного руху елементарних освітянських навичок (вміння читати та писати), які були необхідні для раціонального тлумачен-ня біблійних та релігійних текстів. Поява розгалуженої освітянської системи в громадах менонітів була детермінована специфікою віровчення спільноти, її нагальними релігійними, церковними та громадськими потребами. Зазначимо, що меноніти розглядали шкільництво як один із засобів набуття «освічено-го благочестя»
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