Search

Privacy-utility tradeoff remains as one of the fundamental issues of differentially private machine learning. This paper introduces a geometrically inspired kernel-based approach to mitigate the accuracy-loss issue in classification. In this approach, a representation of the affine hull of given data points is learned in Reproducing Kernel Hilbert Spaces (RKHS). This leads to a novel distance measure that hides privacy-sensitive information about individual data points and improves the privacy-utility tradeoff via significantly reducing the risk of membership inference attacks. The effectiveness of the approach is demonstrated through experiments on MNIST dataset, Freiburg groceries dataset, and a real biomedical dataset. It is verified that the approach remains computationally practical. The application of the approach to federated learning is considered and it is observed that the accuracy-loss due to data being distributed is either marginal or not significantly high.

Macroscopic elastic core-shell systems can be generated as toy models to be deformed and haptically studied by hand. On the mesoscale, colloidal core-shell particles and microgels are fabricated and investigated by different types of microscopy. We analyse, using linear elasticity theory, the response of spherical core-shell systems under the influence of a line density of force that is oriented radially and acts along the equator of the outer surface. Interestingly, deformational coupling of the shell to the core can determine the resulting overall appearance in response to the forces. We address various combinations of radii, stiffness, and Poisson ratio of core and shell and illustrate the resulting deformations. Macroscopically, the situation could be realized by wrapping a cord around the equator of a macroscopic model system and pulling it tight. On the mesoscale, colloidal microgel particles symmetrically confined to the interface between two immiscible fluids are pulled radially outward by surface tension., Comment: 18 pages, 5 figures, article

A fuzzy theoretic analytical approach was recently introduced that leads to efficient and robust models while addressing automatically the typical issues associated to parametric deep models. However, a formal conceptualization of the fuzzy theoretic analytical deep models is still not available. This paper introduces using measure theoretic basis the notion of \emph{membership-mapping} for representing data points through attribute values (motivated by fuzzy theory). A property of the membership-mapping, that can be exploited for data representation learning, is of providing an interpolation on the given data points in the data space. An analytical approach to the variational learning of a membership-mappings based data representation model is considered.

In order to develop machine learning and deep learning models that take into account the guidelines and principles of trustworthy AI, a novel information theoretic trustworthy AI framework is introduced. A unified approach to "privacy-preserving interpretable and transferable learning" is considered for studying and optimizing the tradeoffs between privacy, interpretability, and transferability aspects. A variational membership-mapping Bayesian model is used for the analytical approximations of the defined information theoretic measures for privacy-leakage, interpretability, and transferability. The approach consists of approximating the information theoretic measures via maximizing a lower-bound using variational optimization. The study presents a unified information theoretic approach to study different aspects of trustworthy AI in a rigorous analytical manner. The approach is demonstrated through numerous experiments on benchmark datasets and a real-world biomedical application concerned with the detection of mental stress on individuals using heart rate variability analysis., Comment: arXiv admin note: text overlap with arXiv:2105.04615, arXiv:2104.07060

Zur Verbesserung der elektrochemischen Eigenschaften von SnS2 Anodenmaterialien als Alternativen für Graphit in Lithiumionenbatterien wurden im Rahmen dieser Arbeit zwei unterschiedliche Ansätze mit dem Ziel, Kohlenstoffschichten auf SnS2-Partikel anzubringen, durchgeführt. Im Zuge des mechanochemischen Ansatzes wurden Mahlversuche mit einer Kugelmühle durchgeführt und zunächst passende Parameter für die Methode gesucht. Die Pulver, sowie die nach wissenschaftlichem Standard hergestellten Elektroden, wurden jeweils mittels Rasterelektronenmikroskopie und Röntgenbeugung untersucht. Ausgewählte Pulverproben wurden auch mittels thermischer Analyse hinsichtlich des Kohlenstoffgehaltes untersucht, die Eignung der TGA Methode zur Messung des Kohlenstoffgehaltes wurde vorher nachgewiesen. Es zeigte sich, dass der Kohlenstoffgehalt systematisch höher ist als gemäß Einwaage, dies liegt vermutlich an der unterschiedlichen Haftung der beiden Materialien am Mahlbecher und den Kugeln. Das elektrochemische Verhalten und die Kapazitätsstabilität des auf SnS2 basierenden Elektrodenmaterials konnten einerseits mittels Verkleinerung der Partikelgrößen, hier lieferte das Mahlen für 10 Stunden bei 200 rpm das beste Ergebnis, und andererseits durch Herstellung von SnS2/C Gemischen erreicht werden. Elektroden, deren Pulvergemische für 10 Stunden bei 400 rpm mit 10 % Graphit gemahlen wurden, zeigten herausragende elektrochemische Eigenschaften. Weiters wurde eine Überstruktur von SnS2 gefunden, welche bisher nicht in der Fachliteratur beschrieben ist. Diese entstand nach Mahlen des Pulvers für 10 Stunden bei 400 rpm und konnte mittels Pulverdiffraktometrie kristallografisch beschrieben werden. Die Aufklärung der Phasenumwandlungen bei der stufenweisen elektrochemischen Lithiierung jener Struktur war großteils erfolgreich und zeigt die Unterschiede im Vergleich zu der herkömmlichen SnS2 Struktur auf. Zur weiteren Aufklärung sind Messungen mittels galvanostatic intermittent titration technique (GITT) geplant. Post-mortem XRD Untersuchungen der Elektroden aus Pulvern unter harschen Mahlbedingungen zeigten, dass nach 50 Entlade/Ladezyklen in den meisten Fällen keine kristallinen Strukturen mehr vorhanden sind. Der zweite Ansatz befasste sich mit der Kohlenstoffbeschichtung der SnS2 Anodenmaterialien mittels thermischer Behandlung unter Verwendung von Polyvinylalkohol (PVA) als Kohlenstoffquelle. Leider stellte sich eine thermische Instabilität von SnS2 unter Anwesenheit von PVA bei der zunächst aus reinem SnS2 ermittelten Beschichtungstemperatur von 500 °C heraus. Unter Anwesenheit von PVA wandelt sich SnS2 bei 500 °C zu SnS und Sn2S3 um, wobei der Anteil von SnS mit steigender Behandlungsdauer zunimmt. Nichtsdestotrotz konnten wertvolle Informationen bezüglich Stabilität des Materials und Anwendbarkeit der Beschichtungsmethode gesammelt werden. Die thermische Zersetzung SnS2 von ist eine vielversprechende Synthesemethode für SnS, welches bisher schwer herzustellen war. TG-DTA-MS-FTIR Untersuchen zur Analyse der bei der Zersetzung entstehenden Gasspezies sind geplant. Die beschichteten Proben wurden mit XRD, TGA und SEM untersucht. Dabei bestätigte sich die Ausbildung einer Schicht, allerdings muss in zukünftigen Raman/IR-Messungen noch die Zusammensetzung hinsichtlich ihrer Reinheit geklärt werden. Die elektrochemischen Untersuchungen des Beschichtungsansatzes sind zum Zeitpunkt der Fertigstellung dieser Masterarbeit noch nicht abgeschlossen, versprechen aber interessante mögliche Weiterentwicklungsmöglichkeiten für die Zukunft., Commercially produced Li-ion batteries usually contain graphite as anode active material, this master's thesis goal is the development and improvement of alternative SnS2 anode materials. Two different approaches were performed in order to coat SnS2 with a conducting carbon layer, namely a mechanochemical route (ball milling) and a thermal route. Powders and electrodes were characterized using scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and selected samples were further investigated using thermogravimetric analysis (TGA). The electrochemical performance of prepared coin cells was determined with galvanostatic cycling under potential limitation (GCPL). Preliminary investigations lead to promising ball milling parameters for the first approach, whereas 10 hours seems to be a suitable milling time. Mechanochemical treatment with ball milling successfully improved the electrochemical performance of half cells. Firstly, through the reduction of particle sizes and secondly through the synthesis of SnS2/carbon composite materials. Ball milling for 10 hours at 200 rpm without carbon resulted in lower capacity degradation compared to pristine SnS2 electrodes. Superior results were achieved with SnS2/C composites containing 10 wt. % graphite, whereby the powders were milled for 10 hours at 400 rpm. There was almost no decrease in specific capacity after first cycling and thus a very high coulombic efficiency was detected. Selected samples were further investigated regarding their carbon content using TGA. A trend that the carbon content after ball-milling was higher than expected was shown, that is most probably due to the preferred adhesion of SnS2 onto the milling bowl and spheres. Post-mortem XRD on cycled electrodes after 50 cycles revealed that for powders that were milled with a high value of revolution per minute no crystalline structures were detected anymore. This trend was shown in phase pure samples as well as with additional graphite. Additionally, a new polytype of SnS2, that has not been described by scientific literatures yet, was identified after ball milling for 10 h with 400 rpm. Further investigations regarding its lithiation mechanism during equilibrium discharge were performed. Future work concerning the new polytype of SnS2 is planned using single crystal XRD for structural clarification. The equilibrium discharge states should preferentially be reinvestigated with galvanostatic intermittent titration technique (GITT). The second approach dealt with carbon coating of anode active materials using a thermal method and polyvinyl alcohol (PVA) as carbon source. Unfortunately, the initially promising coating temperature of 500 °C turned out to be unsuccessful in the end, since SnS2 is not stable, neither in its pristine form, nor in a 1:1 wt. mixture with PVA. Under the presence of PVA at 500 °C SnS2 decomposes into SnS and Sn2S, whereby the fraction of SnS rises with rising duration of the treatment. Nevertheless, it was possible to gather valuable information about the conversion of SnS2 and an additional promising way to synthesize SnS was found. TG-DTA-MS-FTIR will be carried out in order to understand the different behavior of SnS2 in presence of PVA regarding the occurring gas species. The powdered samples were investigated using SEM, XRD and partially TGA. The success of coating was shown using SEM. Future work will be performed in order to determine the composition of the coated layer regarding the purity of carbon in detail with IR/Raman-spectroscopy. Electrochemical investigations of the PVA coating approach have not yet been completed by the time this master's thesis ends, but they show promising intermediate data and possible further development opportunities for the future.

Supplemental Material, sj-docx-2-jsr-10.1177_10946705211003676 for Enabling Cocreation With Transformative Interventions: An Interdisciplinary Conceptualization of Consumer Boosting by Martin Bieler, Peter Maas, Lukas Fischer and Nele Rietmann in Journal of Service Research

Supplemental Material, sj-docx-1-jsr-10.1177_10946705211003676 for Enabling Cocreation With Transformative Interventions: An Interdisciplinary Conceptualization of Consumer Boosting by Martin Bieler, Peter Maas, Lukas Fischer and Nele Rietmann in Journal of Service Research

Highly oxygenated organic molecules (HOMs) contribute substantially to the formation and growth of atmospheric aerosol particles, which affect air quality, human health and Earth s climate. HOMs are formed by rapid, gasphase autoxidation of volatile organic compounds (VOCs) such as -pinene, the most abundant monoterpene in the atmosphere. Due to their abundance and low volatility, HOMs can play an important role in new-particle formation (NPF) and the early growth of atmospheric aerosols, even without any further assistance of other low-volatility compounds such as sulfuric acid. Both the autoxidation reaction forming HOMs and their NPF rates are expected to be strongly dependent on temperature. However, experimental data on both effects are limited. Dedicated experiments were performed at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN to address this question. In this study, we show that a decrease in temperature (from C25 to 50 C) results in a reduced HOM yield and reduced oxidation state of the products, whereas the NPF rates (J1:7 nm) increase substantially. Measurements with two different chemical ionization mass spectrometers (using nitrate and protonated water as reagent ion, respectively) provide the molecular composition of the gaseous oxidation products, and a two-dimensional volatility basis set (2D VBS) model provides their volatility distribution. The HOM yield decreases with temperature from 6.2% at 25 C to 0.7% at 50 C. However, there is a strong reduction of the saturation vapor pressure of each oxidation state as the temperature is reduced. Overall, the reduction in volatility with temperature leads to an increase in the nucleation rates by up to 3 orders of magnitude at 50 C compared with 25 C. In addition, the enhancement of the nucleation rates by ions decreases with decreasing temperature, since the neutral molecular clusters have increased stability against evaporation. The resulting data quantify how the interplay between the temperature-dependent oxidation pathways and the associated vapor pressures affect biogenic NPF at the molecular level. Our measurements, therefore, improve our understanding of pure biogenic NPF for a wide range of tropospheric temperatures and precursor concentrations. publishedVersion

Highly oxygenated organic molecules (HOMs) contribute substantially to the formation and growth of atmospheric aerosol particles, which affect air quality, human health and Earth's climate. HOMs are formed by rapid, gas-phase autoxidation of volatile organic compounds (VOCs) such as alpha-pinene, the most abundant monoterpene in the atmosphere. Due to their abundance and low volatility, HOMs can play an important role in new-particle formation (NPF) and the early growth of atmospheric aerosols, even without any further assistance of other low-volatility compounds such as sulfuric acid. Both the autoxidation reaction forming HOMs and their NPF rates are expected to be strongly dependent on temperature. However, experimental data on both effects are limited. Dedicated experiments were performed at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN to address this question. In this study, we show that a decrease in temperature (from + 25 to -50 degrees C) results in a reduced HOM yield and reduced oxidation state of the products, whereas the NPF rates (J(1.7) (nm)) increase substantially. Measurements with two different chemical ionization mass spectrometers (using nitrate and protonated water as reagent ion, respectively) provide the molecular composition of the gaseous oxidation products, and a two-dimensional volatility basis set (2D VBS) model provides their volatility distribution. The HOM yield decreases with temperature from 6.2 % at 25 degrees C to 0.7 % at -50 degrees C. However, there is a strong reduction of the saturation vapor pressure of each oxidation state as the temperature is reduced. Overall, the reduction in volatility with temperature leads to an increase in the nucleation rates by up to 3 orders of magnitude at -50 degrees C compared with 25 degrees C. In addition, the enhancement of the nucleation rates by ions decreases with decreasing temperature, since the neutral molecular clusters have increased stability against evaporation. The resulting data quantify how the interplay between the temperature-dependent oxidation pathways and the associated vapor pressures affect biogenic NPF at the molecular level. Our measurements, therefore, improve our understanding of pure biogenic NPF for a wide range of tropospheric temperatures and precursor concentrations.

Machine translation (MT) has been shown to produce a number of errors that require human post-editing, but the extent to which professional human translation (HT) contains such errors has not yet been compared to MT. We compile pre-translated documents in which MT and HT are interleaved, and ask professional translators to flag errors and post-edit these documents in a blind evaluation. We find that the post-editing effort for MT segments is only higher in two out of three language pairs, and that the number of segments with wrong terminology, omissions, and typographical problems is similar in HT., EAMT 2020 (Research Track)

Soft elastic composite materials can serve as actuators when they transform changes in external fields into mechanical deformation. Here, we address the corresponding deformational behavior of magnetic gels and elastomers, consisting of magnetizable colloidal particles in a soft polymeric matrix and exposed to external magnetic fields. Since many practical realizations of such materials involve particulate inclusions of polydisperse size distributions, we concentrate on the effect that mixed particle sizes have on the overall deformational response. To perform a systematic study, our focus is on binary size distributions. We systematically vary the fraction of larger particles relative to smaller ones and characterize the resulting magnetostrictive behavior. The consequences for systems of various different spatial particle arrangements and different degrees of compressibility of the elastic matrix are evaluated. In parts, we observe a qualitative change in the overall response for selected systems of mixed particle sizes. Specifically, overall changes in volume and relative elongations or contractions in response to an induced magnetization can be reversed into the opposite types of behavior. Our results should apply to the characteristics of other soft elastic composite materials like electrorheological gels and elastomers when exposed to external electric fields as well. Overall, we hope to stimulate the further investigation on the purposeful use of mixed particle sizes as a means to design tailored requested material behavior., 14 pages, 17 figures

A recent result of stochastic thermodynamics is the so-called thermodynamic uncertainty relation (TUR). This relation, appearing in the form of an inequality, bounds the precision of fluctuating currents by the entropic costs that are required to drive the non-vanishing mean of the observable. As a consequence, the relation enables the access to parameters that are not accessible in an experimental setting via the precision of a experimentally accessible observable. For instance, it was possible to bound the efficiency of molecular machines by means of their measurable moments of motion. Albeit being generalized and modified to more general terms and dynamics, the putative generalization of the thermodynamic uncertainty relation to underdamped dynamics where the inertia is not negligible remains a puzzling problem. Although there are convincing indications for the overdamped TUR being valid for underdamped dynamics as well in some systems, a straightforward application can also lead to violations of the bound. This thesis summarizes the efforts towards an underdamped generalization of the thermodynamic uncertainty relation and shows challenges and chances that come along by generalization of the TUR. To this end, the intriguing limitations of the TUR in the underdamped domain are explored and discussed. For instance, the TUR is inherently broken for finite times where the evolution is governed by ballistic dynamics due to the inertia being present. Furthermore, it is possible to improve the precision beyond the overdamped bound in presence of velocity dependent forces such as the Lorentz force induced by a magnetic field. Beyond the limitations of the TUR in the underdamped regime, this thesis gives a thorough analysis of the proof that leads to the TUR in the overdamped regime and discusses the obstacles which have to be overcome to find the sought-after proof that is valid for underdamped dynamics. The method is illustrated by deriving thermodynamic bounds that are, however, not as transparent and often not as tight as the original TUR. Finally, a conjecture for a generalized TUR is presented which is based on the precision of free diffusion and holds for all times. The corresponding bound converges to the overdamped TUR in the appropriate limit and tightly bounds the precision, even in the ballistic regime. Being based on free diffusion this conjecture also puts the interpretation of the original TUR in a different perspective.

Die vorliegende Arbeit beschäftigt sich mit dem § 365 im Bundesvergabegesetz 2018 und den darin enthaltenen Regelungen für wesentliche und unwesentliche Vertragsänderungen während der Laufzeit. Der § 365 BVergG 2018 setzt in Österreich den Artikel 72 der europäischen Vergaberichtlinie 24/2014/EU in nationales Recht um. Der Artikel 72 entwickelte sich aus Urteilen des EuGH zum Vergaberecht, die die Grundsätze der EU „Nichtdiskriminierung, Gleichbehandlung, Transparenz und Verhältnismäßigkeit“ berücksichtigt haben. Das Vergabegesetz bestimmt den Gegenstand von wesentlichen und unwesentlichen Änderungen und ob diese zu einer erneuten Durchführung des Vergabeverfahrens führen müssen, siehe Prüfschema Kap. 4.7. Das Bauvertragsrecht regelt mit den allgemeinen Vertragsbestimmungen der Werkvertragsnorm ÖNORM B 2110 und den darin enthalten Leistungsänderungsklauseln Änderungen von Verträgen während der Laufzeit. Durch den Eingriff des Vergaberechts in das Bauvertragsrecht ergibt sich folgende Fragestellung: Sind die definierten Leistungsänderungsklauseln in der ÖNORM B2110 als unwesentliche Änderungen im Sinne des BVergG 2018 zu sehen? Denn nach § 365 Abs. 3, Z 2 müssen Vertragsänderungsklauseln klar, präzise und eindeutig formuliert sein. Bei der Überprüfung der Leistungsänderungsklauseln der ÖNORM im Sinne der Vertragsänderungsklausel Vergabegesetzes zeigte sich, dass nur die Preisanpassung als solche gesehen werden kann. Die weiteren Leistungsänderungsklauseln der ÖNORM können nur mittels einer Einzelfallbetrachtung bewertet werden. Das ursprüngliche Prüfschema zum § 365 wurde unter Berücksichtigung der Grundsätze der EU angepasst. In der weiteren Praxis wird sich zeigen, wie sich das Zusammenspiel zwischen Vergabegesetz und dem Bauvertragsrecht entwickelt. Diese Weiterentwicklung ist vor allem abhängig von der zukünftigen österreichischen und europäischen Rechtsprechung. This thesis deals with § 365 of the Federal Public Procurement Act 2018 and the regulations contained therein for substantial and insignificant changes to contracts during their term. § 365 BVergG 2018 converts Article 72 of the European Public Procurement Directive 24/2014/EU into Austrian national law. Article 72 developed from decisions of the European Court of Justice on public procurement law which took into account EU principles of non-discrimination, equal treatment, transparency and proportionality. The Public Procurement Act defines the subject of substantial and insignificant modifications and whether these must lead to a renewed performance of the procurement procedure, see the check scheme in chapter 4.7. The construction contract law regulate with the general contractual terms of the work contract standard ÖNORM B 2110 and the performance modification clauses contained therein modifications of contracts during the term. Due to the interference of the public procurement law with the construction contract law, the following question arises: Can the defined performance modification clauses in ÖNORM B2110 be seen as insignificant changes in the sense of BVergG 2018? According to § 365, Subsection 3, Line 2, contract modification clauses must be formulated in clear, precise and unequivocal terms. The review of the performance modification clauses of ÖNORM in terms of the contract modification clause of the Austrian Public Procurement Act showed that only the price adjustment can be seen as such. The other performance modification clauses of ÖNORM can only be assessed on a case-by-case basis. The original check scheme for § 365 has been adapted in consideration of the principles of the EU. Further practice will show how the interaction between the Public Procurement Act and the Construction Contract Law develops. This further development depends above all on the future Austrian and European jurisdiction. vorgelegt von: Lukas Fischer Auch als Printexemplar verfügbar Masterarbeit Wien, FH Campus Wien 2020

Plugins erweitern die Funktionalität von WordPress und helfen Webseitenbetreibern beim Hinzufügen neuer Elemente oder Funktionen. Dabei muss der Betreiber selbst keinen komplexen Programmcode schreiben. Auch können diese Erweiterungen als Erleichterung bei der Pflege von Informationen und Inhalten dienen. In der vorliegenden Bachelorarbeit wird die Konzipierung, Umsetzung und Anwendung eines solchen Plugins für den Vergleich von Veranstaltungen beschrieben. Dabei findet es Anwendung auf einer Internetseite zum Thema Festivals. Die Informationen bezüglich der Festivals werden per Import in einer Tabelle gespeichert und für den Vergleich dargestellt. Eintragungen können auch händisch getätigt werden, woraus sich schließlich ergibt, dass das Plugin mit seiner Importfunktion eine zeitsparende und sinnvolle Erweiterung ist.

We report high-resolution capacitance dilatometry studies on the uniaxial length changes in a NdB$_4$ single crystal. The evolution of magnetically ordered phases below $T_{\rm N}$= 17.2~K (commensurate antiferromagnetic phase, cAFM), $T_{\rm IT}$= 6.8~K (intermediate incommensurate phase, IT), and $T_{\rm LT}$= 4.8~K (low-temperature phase, LT) is associated with pronounced anomalies in the thermal expansion coefficients. The data imply significant magneto-elastic coupling and evidence of a structural phase transition at $T_{\rm LT}$ . While both cAFM and LT favor structural anisotropy $��$ between in-plane and out-of-plane length changes, it competes with the IT-type of order, i.e., $��$ is suppressed in that phase. Notably, finite anisotropy well above $T_{\rm N}$ indicates short-range correlations which are, however, of neither cAFM, IT, nor LT-type. Gr��neisen analysis of the ratio of thermal expansion coefficient and specific heat enables the derivation of uniaxial as well as hydrostatic pressure dependencies. While $��$/$c_{\rm p}$ evidences a single dominant energy scale in LT, our data imply precursory fluctuations of a competing phase in IT and cAFM, respectively. Our results suggest the presence of orbital degrees of freedom competing with cAFM and successive evolution of a magnetically and orbitally ordered ground state.

Separating and labeling each instance of a nucleus (instance-aware segmentation) is the key challenge in segmenting single cell nuclei on fluorescence microscopy images. Deep Neural Networks can learn the implicit transformation of a nuclear image into a probability map indicating the class membership of each pixel (nucleus or background), but the use of post-processing steps to turn the probability map into a labeled object mask is error-prone. This especially accounts for nuclear images of tissue sections and nuclear images across varying tissue preparations. In this work, we aim to evaluate the performance of state-of-the-art deep learning architectures to segment nuclei in fluorescence images of various tissue origins and sample preparation types without post-processing. We compare architectures that operate on pixel to pixel translation and an architecture that operates on object detection and subsequent locally applied segmentation. In addition, we propose a novel strategy to create artificial images to extend the training set. We evaluate the influence of ground truth annotation quality, image scale and segmentation complexity on segmentation performance. Results show that three out of four deep learning architectures (U-Net, U-Net with ResNet34 backbone, Mask R-CNN) can segment fluorescent nuclear images on most of the sample preparation types and tissue origins with satisfactory segmentation performance. Mask R-CNN, an architecture designed to address instance aware segmentation tasks, outperforms other architectures. Equal nuclear mean size, consistent nuclear annotations and the use of artificially generated images result in overall acceptable precision and recall across different tissues and sample preparation types., 10 pages + 3 supplementary pages

The recent success of Generative Adversarial Networks (GAN) is a result of their ability to generate high quality images from a latent vector space. An important application is the generation of images from a text description, where the text description is encoded and further used in the conditioning of the generated image. Thus the generative network has to additionally learn a mapping from the text latent vector space to a highly complex and multi-modal image data distribution, which makes the training of such models challenging. To handle the complexities of fashion image and meta data, we propose Ontology Generative Adversarial Networks (O-GANs) for fashion image synthesis that is conditioned on an hierarchical fashion ontology in order to improve the image generation fidelity. We show that the incorporation of the ontology leads to better image quality as measured by Fr\'{e}chet Inception Distance and Inception Score. Additionally, we show that the O-GAN achieves better conditioning results evaluated by implicit similarity between the text and the generated image., Comment: Under review at MLKgraphs2019: http://www.dexa.org/mlkgraphs2019

A major fraction of atmospheric aerosol particles, which affect both air quality and climate, form from gaseous precursors in the atmosphere. Highly oxygenated organic molecules (HOMs), formed by oxidation of biogenic volatile organic compounds, are known to participate in particle formation and growth. However, it is not well understood how they interact with atmospheric pollutants, such as nitrogen oxides (NOx) and sulfur oxides (SOx) from fossil fuel combustion, as well as ammonia (NH3) from livestock and fertilizers. Here, we show how NOx suppresses particle formation, while HOMs, sulfuric acid, and NH3 have a synergistic enhancing effect on particle formation. We postulate a novel mechanism, involving HOMs, sulfuric acid, and ammonia, which is able to closely reproduce observations of particle formation and growth in daytime boreal forest and similar environments. The findings elucidate the complex interactions between biogenic and anthropogenic vapors in the atmospheric aerosol system., Science Advances, 4 (12), ISSN:2375-2548

Summary: The integration of visual stimuli and motor feedback is critical for successful visually guided navigation. These signals have been shown to shape neuronal activity in the primary visual cortex (V1), in an experience-dependent manner. Here, we examined whether visual, reward, and self-motion-related inputs are integrated in order to encode behaviorally relevant locations in V1 neurons. Using a behavioral task in a virtual environment, we monitored layer 2/3 neuronal activity as mice learned to locate a reward along a linear corridor. With learning, a subset of neurons became responsive to the expected reward location. Without a visual cue to the reward location, both behavioral and neuronal responses relied on self-motion-derived estimations. However, when visual cues were available, both neuronal and behavioral responses were driven by visual information. Therefore, a population of V1 neurons encode behaviorally relevant spatial locations, based on either visual cues or on self-motion feedback when visual cues are absent. : Pakan et al. show that spatial locations that are relevant for a behavioral task are represented in the primary visual cortex. Both neuronal and behavioral responses to an expected reward location primarily rely on visual information. Without visual landmarks, both neuronal and behavioral responses are driven by self-motion derived information. Keywords: visual cortex, awake behaving mice, two-photon calcium imaging, virtual reality, reward, navigation, motor feedback, visual landmark, V1, path integration

We have developed and characterized the novel PTR3, a proton transfer reaction-time-of-flight mass spectrometer (PTR-TOF) using a new gas inlet and an innovative reaction chamber design. The reaction chamber consists of a tripole operated with rf voltages generating an electric field only in the radial direction. An elevated electrical field is necessary to reduce clustering of primary hydronium (H3O+) and product ions with water molecules present in the sample gas. The axial movement of the ions is achieved by the sample gas flow only. Therefore, the new design allows a 30-fold longer reaction time and a 40-fold increase in pressure compared to standard PTR-TOF-MS. First calibration tests show sensitivities of up to 18000 counts per second/parts per billion and volume (cps/ppbv) at a mass resolution of >8000 m/Δm (fwhm). The new inlet using center-sampling through a critical orifice reduces wall losses of low volatility compounds. Therefore, the new PTR3 instrument is sensitive to VOC typically present in the ppbv range as well as to semivolatile organic compounds (SVOC) and even highly oxidized organic molecules (HOMs) present in the parts per quadrillion per volume (ppqv) range in the atmosphere.

Background Various medical fields rely on detailed anatomical knowledge of the distal radius. Current studies are limited to two-dimensional analysis and biased by varying measurement locations. The aims were to 1) generate 3D shape models of the distal radius and investigate variations in the 3D shape, 2) generate and assess morphometrics in standardized cut planes, and 3) test the model’s classification accuracy. Methods The local radiographic database was screened for CT-scans of intact radii. 1) The data sets were segmented and 3D surface models generated. Statistical 3D shape models were computed (overall, gender and side separate) and the 3D shape variation assessed by evaluating the number of modes. 2) Anatomical landmarks were assigned and used to define three standardized cross-sectional cut planes perpendicular to the main axis. Cut planes were generated for the mean shape models and each individual radius. For each cut plane, the following morphometric parameters were calculated and compared: maximum width and depth, perimeter and area. 3) The overall shape model was utilized to evaluate the predictive value (leave one out cross validation) for gender and side identification within the study population. Results Eighty-six radii (45 left, 44% female, 40 ± 18 years) were included. 1) Overall, side and gender specific statistical 3D models were successfully generated. The first mode explained 37% of the overall variance. Left radii had a higher shape variance (number of modes: 20 female / 23 male) compared to right radii (number of modes: 6 female / 6 male). 2) Standardized cut planes could be defined using anatomical landmarks. All morphometric parameters decreased from distal to proximal. Male radii were larger than female radii with no significant side difference. 3) The overall shape model had a combined median classification probability for side and gender of 80%. Conclusions Statistical 3D shape models of the distal radius can be generated using clinical CT-data sets. These models can be used to assess overall bone variance, define and analyze standardized cut-planes, and identify the gender of an unknown sample. These data highlight the potential of shape models to assess the 3D anatomy and anatomical variance of human bones. Electronic supplementary material The online version of this article (doi:10.1186/s12880-017-0193-9) contains supplementary material, which is available to authorized users.

Animated illustration of the cross-sectional cut planes. Green plane: Proximal plane (50% of the distance between the tip of the styloid process and the most dorsal point of the tuberculum listerii); Blue plane: Middle plane (Half way between the distal and proximal sectional plane); Red plane: Distal plane (The most dorsal point of the tuberculum listerii). (PDF 140 kb)

Summary of morphometric parameters (Mean, Âą1SD) of the mean shape model for all three sectional planes. SD: Standard deviation; Distal: Distal plane; Middle: Middle plane; Proximal: Proximal plane. (DOCX 113 kb)

Detailed description of the process of shape model generation. (DOCX 92 kb)

Archäologie in Westfalen-Lippe, ARCHÄOLOGIE IN WESTFALEN-LIPPE 2014 (2015)

Path integration is the ability to navigate to a goal location without using external cues, thus relying entirely on self-motion information. To do so, two components of a path need to be encoded: orientation and distance. While the ability to estimate distance, called linear path integration, is well established in humans, it is unclear whether rodents are equally capable of doing so and the underlying neural circuit mechanisms are only poorly understood. This thesis discusses the development of a virtual reality system and behavioural task to investigate linear path integration in mice, and the results obtained from experiments carried out with this system. The setup provides full control over visual input while de-correlating vestibular and olfactory signals from location. Manipulations of the translation from physical to virtual movement can thus be used to probe relative influences of motor related and visual signals. Chapter 1 reviews the current literature on path integration and provides a background to the technical setup of the system. Chapter 2 describes the design and construction of the virtual reality system, its individual components and the software created to run experiments. It discusses how 3-d modelling and 3-d printing have successfully been combined to allow rapid development and production of custom components in different materials. Chapter 3 discusses the development of behavioural tasks designed to investigate linear path integration. It shows that by using a simple virtual track design and a carefully monitored food-deprivation regime, mice can be trained to successfully associate a visually indicated location with a reward. Chapter 4 describes behavioural experiments carried out using this virtual linear track. I obtained evidence that mice can estimate the distance to the rewarded zone reliably using path integration strategies. To test whether mice rely on motor information or optic flow, I manipulated the gain between physical movement and virtual movement. My results suggest that mice primarily rely on motor information for linear path integration. In the final chapter the results are discussed in the context of other recent work and areas for further development of the system are identified.

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: High resolution peripheral quantitative computed tomography (HR-pQCT) can be used for the non-invasive assessment of changes in bone microarchitecture. While the majority of studies have been cross-sectional in design, longitudinal data are still...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: New onset osteoporosis or progression of a pre-existing disease with bone fractures within the first years after lung-transplantation (LuTX) is a severe but poorly understood problem. High resolution peripheral quantitative computed tomography...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: High-resolution peripheral quantitative computed tomography (HR-pQCT, XtremCT, Scanco Mecdical AG, Switzerland) is a novel noninvasive technique to acquire high-resolution images of the bone microarchitecture. Recently Mueller et. al [1] showed...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: Segmentation approaches based on Shape Particle Filters deliver promising results for the localization of anatomical structures in medical images. They are used for the segmentation of human vertebrae, lungs and hearts, and are especially well...

Highlights • The coupling of PTR-TOFMS to a fast GC system using a multi-capillary column was successfully implemented. • The built set-up enables the separation of structural isomers within seconds and does not hamper the normal operation of the PTR-TOFMS. • The MCC setup is suitable to be installed inside the instrument and the overall retention time for a complete spectrum is only a few minutes. • Besides, MCC-PTR-TOF allows a more accurate identification of compounds in complex mixtures., Proton-transfer-reaction time-of-flight mass-spectrometry (PTR-TOFMS) exhibits high selectivity with a resolution of around 5000 m/Δm. While isobars can be separated with this resolution, discrimination of isomeric compounds is usually not possible. The coupling of a multi-capillary column (MCC) with a PTR-TOFMS overcomes these problems as demonstrated in this paper for the ketone isomers 3-heptanone and 2-methyl-3-hexanone and for different aldehydes. Moreover, fragmentation of compounds can be studied in detail which might even improve the identification. LODs for compounds tested are in the range of low ppbv and peak positions of the respective separated substances show good repeatability (RSD of the peak positions

Nucleation of atmospheric vapours produces more than half of global cloud condensation nuclei and so has an important influence on climate. Recent studies show that monoterpene (C10H16) oxidation yields highly oxygenated products that can nucleate with or without sulfuric acid. Monoterpenes are emitted mainly by trees, frequently together with isoprene (C5H8), which has the highest global emission of all organic vapours. Previous studies have shown that isoprene suppresses new-particle formation from monoterpenes, but the cause of this suppression is under debate. Here, in experiments performed under atmospheric conditions in the CERN CLOUD chamber, we show that isoprene reduces the yield of highly oxygenated dimers with 19 or 20 carbon atoms - which drive particle nucleation and early growth - while increasing the production of dimers with 14 or 15 carbon atoms. The dimers (termed C-20 and C-15, respectively) are produced by termination reactions between pairs of peroxy radicals (RO2 center dot) arising from monoterpenes or isoprene. Compared with pure monoterpene conditions, isoprene reduces nucleation rates at 1.7 nm (depending on the isoprene = monoterpene ratio) and approximately halves particle growth rates between 1.3 and 3.2 nm. However, above 3.2 nm, C-15 dimers contribute to secondary organic aerosol, and the growth rates are unaffected by isoprene. We further show that increased hydroxyl radical (OH center dot) reduces particle formation in our chemical system rather than enhances it as previously proposed, since it increases isoprene-derived RO2 center dot radicals that reduce C-20 formation. RO2 center dot termination emerges as the critical step that determines the highly oxygenated organic molecule (HOM) distribution and the corresponding nucleation capability. Species that reduce the C-20 yield, such as NO, HO2 and as we show isoprene, can thus effectively reduce biogenic nucleation and early growth. Therefore the formation rate of organic aerosol in a particular region of the atmosphere under study will vary according to the precise ambient conditions., Atmospheric Chemistry and Physics, 20 (20), ISSN:1680-7375, ISSN:1680-7367

Atmospheric new-particle formation (NPF) affects climate by contributing to a large fraction of the cloud condensation nuclei (CCN). Highly oxygenated organic molecules (HOMs) drive the early particle growth and therefore substantially influence the survival of newly formed particles to CCN. Nitrogen oxide (NOx) is known to suppress the NPF driven by HOMs, but the underlying mechanism remains largely unclear. Here, we examine the response of particle growth to the changes of HOM formation caused by NOx. We show that NOx suppresses particle growth in general, but the suppression is rather nonuniform and size dependent, which can be quantitatively explained by the shifted HOM volatility after adding NOx. By illustrating how NOx affects the early growth of new particles, a critical step of CCN formation, our results help provide a refined assessment of the potential climatic effects caused by the diverse changes of NOx level in forest regions around the globe., Science Advances, 6 (22), ISSN:2375-2548