cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Chemerin in Liver Diseases
Creators: name: Buechler, Christa
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: Hepatocellular carcinoma; NASH; Hepatitis C; Adipokines
subject: 610 Medizin

description: Chemerin is a chemoattractant protein and moreover has a role in adipogenesis, angiogenesis and glucose homeostasis. Chemerin is primarily synthesized and secreted by adipocytes and hepatocytes. Chemerin receptors chemokine-like receptor 1 (CMKLR1), G-protein coupled receptor 1 (GPR1) and CC-motif chemokine receptorlike 2 (CCRL2) are all expressed in the liver suggesting that chemerin may be relevant in liver physiology and pathophysiology. Non-alcoholic fatty liver disease (NAFLD) is associated with obesity and is the most common cause of chronic liver injury. NAFLD and chronic hepatitis C virus infection are risk factors for hepatocellular carcinoma. Hepatic and serum chemerin have been analyzed in human and rodent NAFLD, in patients with chronic hepatitis C and patients with hepatocellular carcinoma. Chemerin, GPR1 and CMKLR1 deficient mice have been used to elucidate the role of these proteins in body weight gain and glucose homeostasis. The regulation of chemerin and CMKLR1 by adipokines, hormones and cytokines relevant in liver diseases has been studied in hepatocytes. The data published so far are briefly summarized herein. Current experimental findings do not provide evidence for a crucial role of chemerin in chronic liver diseases and further research is needed to evaluate a possible protective function of this protein in hepatocellular carcinoma.
Why Quantum Theory is Possibly Wrong
Creators: name: Lyre, Holger
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: History and Philosophy of Physics (physics.hist-ph)
subject: FOS: Physical sciences

description: Quantum theory is a tremendously successful physical theory, but nevertheless suffers from two serious problems: the measurement problem and the problem of interpretational underdetermination. The latter, however, is largely overlooked as a genuine problem of its own. Both problems concern the doctrine of realism, but pull, quite curiously, into opposite directions. The measurement problem can be captured such that due to scientific realism about quantum theory common sense anti-realism follows, while theory underdetermination usually counts as an argument against scientific realism. I will also consider the more refined distinctions of ontic and epistemic realism and demonstrate that quantum theory in its most viable interpretations conflicts with at least one of the various realism claims. A way out of the conundrum is to come to the bold conclusion that quantum theory is, possibly, wrong (in the realist sense).
"A living history" : ancient Rome on Wilson Barrett's stage
Creators: name: Hereld, Shoshana
Publisher: name: University of British Columbia
Year: 2017

description: The toga dramas of late nineteenth-century British actor-manager Wilson Barrett provide important evidence on the relationship between the Classics and Victorian theater. In his depictions of ancient Rome, Barrett married the popularity of melodrama with the passion for classical antiquity, reflecting changes in the Victorian social world at the end of the nineteenth century: the increasing prominence of melodrama and the blurring of artistic genres; the increasing accessibility of classical knowledge; and obsessions with historicity. Drawing on scripts, contemporary reviews, and photographs, I investigate the ways in which Barrett’s work navigates the existing social scene in both theater and society at large. By exploring the splendor of Victorian melodrama, the British tastes for the Classics, and the relationship between authenticity and theatricality, this thesis uses Wilson Barrett’s work to demonstrate important features of both Victorian theater and society at large at the end of the nineteenth century.
Empirical processes, typical sequences and coordinated actions in standard Borel spaces
Creators: name: Raginsky, Maxim
Publisher: name: arXiv
Year: 2010
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: This paper proposes a new notion of typical sequences on a wide class of abstract alphabets (so-called standard Borel spaces), which is based on approximations of memoryless sources by empirical distributions uniformly over a class of measurable "test functions." In the finite-alphabet case, we can take all uniformly bounded functions and recover the usual notion of strong typicality (or typicality under the total variation distance). For a general alphabet, however, this function class turns out to be too large, and must be restricted. With this in mind, we define typicality with respect to any Glivenko-Cantelli function class (i.e., a function class that admits a Uniform Law of Large Numbers) and demonstrate its power by giving simple derivations of the fundamental limits on the achievable rates in several source coding scenarios, in which the relevant operational criteria pertain to reproducing empirical averages of a general-alphabet stationary memoryless source with respect to a suitable function class.
description: 14 pages, 3 pdf figures; accepted to IEEE Transactions on Information Theory
Action, opinion, identity : free speech and Hannah Arendt
Creators: name: Marshall, Holly Alexandra Christina
Publisher: name: The University of St Andrews
Year: 2022
Subjects: subject: Hannah Arendt
subject: Arendt
subject: Free speech
subject: Freedom of speech
subject: Freedom
subject: Action
subject: Opinion
subject: Identity
subject: Hate speech
subject: Judgement
subject: Kant
subject: JC251.A74M2
subject: Arendt, Hannah, 1906-1975--Political and social views
subject: Freedom of speech

description: This thesis seeks to provide a political-theoretical account of free speech in the thought of Hannah Arendt. The thesis derives from the observation that the existing literature on free speech fails to develop the concept of free speech on its own terms, either outsourcing the question to legal theory, or, especially in the case of liberal accounts, simply finding reasons to value or limit free speech on the basis of some other political or social good. Arendt offers an alternative framework for conceptualising free speech as both a political faculty and the experience of freedom, which she conceived as a public phenomenon and a state of being. Free speech on an Arendtian reading is therefore irreducible to the condition of rights or instrumental ends. To make this case, the thesis will delineate three separate and related dimensions of speech and freedom through a close exegetical reading of Arendt. First, Arendt’s phenomenology of action will be shown to yield an understanding of free speech as a capacity of the individual and the faculty of the will, by which one can either confirm or resist reality and potentially start something new. Second, free speech will be shown to be necessary for opinion formation, and an indispensable predicate for political judgment, thinking, and truth. Third, speech will be discussed with reference to Arendt’s Nietzschean concept of identity, whereby we manifest and become “one” with ourselves only in the light of the public and in the course of communication with others. The thesis ends with an Arendtian analysis of hate speech. Since Arendt considers both speech and hate to be essentially political phenomena, the argument will be made that hate is therefore best countered and pre-empted in the political sphere. It further argues that the “hate speech turn” is in fact an effect of the condition of powerlessness, which Arendt understood to be impotence of action, and the irrelevance – and therefore unfreedom – of one’s speech.
Proceedings Fourth Workshop on Membrane Computing and Biologically Inspired Process Calculi 2010
Creators: name: Ciobanu, Gabriel
name: Koutny, Maciej
Publisher: name: arXiv
Year: 2010
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences
subject: F.1.1; F.1.2

description: The 4th Workshop on Membrane Computing and Biologically Inspired Process Calculi (MeCBIC 2010) is organized in Jena as a satellite event of the Eleventh International Conference on Membrane Computing (CMC11). Biological membranes play a fundamental role in the complex reactions which take place in cells of living organisms. The importance of this role has been considered in two different types of formalisms introduced recently. Membrane systems were introduced as a class of distributed parallel computing devices inspired by the observation that any biological system is a complex hierarchical structure, with a flow of biochemical substances and information that underlies their functioning. The modeling and analysis of biological systems has also attracted considerable interest of the process algebra research community. Thus the notions of membranes and compartments have been explicitly represented in a family of calculi, such as ambients and brane calculi. A cross fertilization of these two research areas has recently started. A deeper investigation of the relationships between these related formalisms is interesting, as it is important to understand the crucial similarities and the differences. The main aim of the workshop is to bring together researchers working on membrane computing, in biologically inspired process calculi, and in other related fields, in order to present recent results and to discuss new ideas concerning such formalisms, their properties and relationships.
Fiber Fabry-Perot cavity with high finesse
Creators: name: Hunger, David
name: Steinmetz, Tilo
name: Colombe, Yves
name: Deutsch, Christian
name: Hänsch, Theodor W.
name: Reichel, Jakob
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have realized a fiber-based Fabry-Perot cavity with CO2 laser-machined mirrors. It combines very small size, high finesse F>=130000, small waist and mode volume, and good mode matching between the fiber and cavity modes. This combination of features is a major advance for cavity quantum electrodynamics (CQED), as shown in recent CQED experiments with Bose-Einstein condensates enabled by this cavity [Y. Colombe et al., Nature 450, 272 (2007)]. It should also be suitable for a wide range of other applications, including coupling to solid-state emitters, gas detection at the single-particle level, fiber-coupled single-photon sources and high-resolution optical filters with large stopband.
description: Submitted to New J. Phys.
Benzoisoxazolone-based scaffolds for development of diversity driven small molecule libraries : an effective tool to identify novel molecules targeting key therapeutic applications
Creators: name: Gong, Ying
Publisher: name: University of British Columbia
Year: 2017

description: The screening of compound libraries has repeatedly demonstrated its effectiveness as a research tool in drug discovery. Parallel synthesis is a powerful approach for the assembly of compound libraries possessing a wide range of structural and functional group diversity for evaluation against both new and established biological targets. This thesis project was focused on the development of four amino and/or carboxy-substituted benzoisoxazolone (B to E) as privileged scaffolds for the parallel synthesis of diversity driven libraries to identify isoform selective inhibitors of Rho-kinase (ROCK) for the treatment of diabetic cardiovascular disease and different cancers, as well as potential anti-HIV agents that block HIV pre-mRNA alternative splicing, and inhibitors of protein arginine methyltransferase 4 (PRMT4) for the treatment of cancer. In the context of developing a synthesis to the C5-amino substituted benzoisoxazolone scaffold B, the general methodology to construct the benzoisoxazolone ring system found in all four scaffolds is described. This involved reaction of a requisite salicylic acid derivative with hydroxylamine followed by dehydrative cyclization to assemble the isoxazolone ring. Also described in Chapter 2 was the synthesis of the C4-amino substituted scaffold C. The crucial issue encountered was control of chemoselectivity during dehydrative ring closure. The intent was that scaffold B and C-based libraries would contain type 2 ROCK inhibitors. The concept described in Chapter 3 was the “formal” use of the C5-carboxy substituted benzoisoxazolone scaffold D to generate novel molecules that mimic the tetracyclic indole anti-HIV agent IDC16, through conservation of the central (B and C-rings) in its structure. Based on the results of virtual screening/docking experiments on PRMT4, chapter 4 describes the synthesis of the 5-carboxy-7-amino substituted benzoisoxazolone scaffold E and its functionalization such that the benzyl substituents introduced at N-2 and the 5-benzamide motif interact with hydrophobic residues along the PRMT4 substrate binding site, and that the appending side chain at position 7, incorporating a urea sub-element, binds strongly in the arginine binding region in PRMT4. Overall, the synthesis of scaffolds B to E on a multigram scale has been achieved, opening the way for diversity driven parallel synthesis of novel compound libraries.
Haemolymph extraction of adult Drosophila
Creators: name: Brembs, Björn
name: Damrau, Christine
Publisher: name: Universität Regensburg
Year: 2013
Subjects: subject: haemolymph, drosophila, method
subject: 570 Biowissenschaften, Biologie
subject: 590 Tiere (Zoologie)

description: The figure shows the very simple protocol of how to extract haemolymph from adult Drosophila melanogaster.
Tidal Excitation of Oscillation Modes in Compact White Dwarf Binaries: I. Linear Theory
Creators: name: Fuller, James
name: Lai, Dong
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We study the tidal excitation of gravity modes (g-modes) in compact white dwarf binary systems with periods ranging from minutes to hours. As the orbit of the system decays via gravitational radiation, the orbital frequency increases and sweeps through a series of resonances with the g-modes of the white dwarf. At each resonance, the tidal force excites the g-mode to a relatively large amplitude, transferring the orbital energy to the stellar oscillation. We calculate the eigenfrequencies of g-modes and their coupling coefficients with the tidal field for realistic non-rotating white dwarf models. Using these mode properties, we numerically compute the excited mode amplitude in the linear approximation as the orbit passes though the resonance, including the backreaction of the mode on the orbit. We also derive analytical estimates for the mode amplitude and the duration of the resonance, which accurately reproduce our numerical results for most binary parameters. We find that the g-modes can be excited to a dimensionless (mass-weighted) amplitude up to 0.1, with the mode energy approaching $10^{-3}$ of the gravitational binding energy of the star. This suggests that thousands of years prior to the binary merger, the white dwarf may be heated up significantly by tidal interactions. However, more study is needed since the physical amplitudes of the excited oscillation modes become highly nonlinear in the outer layer of the star, which can reduce the mode amplitude attained by tidal excitation.
description: 10 pages, 8 figures
Spitzer observations of supernova remnants: II. Physical conditions and comparison with HH7 and HH54
Creators: name: Yuan, Yuan
name: Neufeld, David A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We have studied the shock-excited molecular regions associated with four supernova remnants (SNRs) - IC443C, W28, W44 and 3C391 - and two Herbig-Haro objects, HH7 and HH54, using Spitzer's Infrared Spectrograph (IRS). The physical conditions within the observed areas are inferred from spectroscopic data obtained from IRS and from SWS and LWS onboard ISO, together with photometric data from Spitzer's Infrared Array Camera (IRAC). Adopting a power-law distribution for the gas temperature in the observed region, the H2 S(0) to S(7) spectral line maps obtained with IRS were used to constrain the gas density, yielding estimated n(H2) in the range 2-4*10^3 cm^-3. The excitation of H2 S(9) to S(12) and high-J CO pure rotational lines, however, require environments several times denser. The inconsistency among the best-fit densities estimated from different species can be explained by density fluctuations within the observed regions. The best-fit power-law index b is smaller than the value 3.8 predicted for a paraboloidal C-type bow shock, suggesting that the shock front has a "flatter" shape than that of a paraboloid. The best-fit parameters for SNRs and Herbig-Haro objects do not differ significantly between the two classes of sources, except that for the SNRs the ortho-to-para ratio (OPR) of hot gas (T> 1000 K) is close to the LTE value 3, while for HH7 and HH54 even the hottest gas exhibits an OPR smaller than 3. Finally, we mapped the physical parameters within the regions observed with IRS and found that the mid-lying H2 emissions - S(3) to S(5) - tend to trace the hot component of the gas, while the intensities of S(6) and S(7) are more sensitive to the density of the gas compared to S(3) to S(5).
The Stretch Factor of the Delaunay Triangulation Is Less Than 1.998
Creators: name: Xia, Ge
Publisher: name: arXiv
Year: 2011
Subjects: subject: Computational Geometry (cs.CG)
subject: FOS: Computer and information sciences
subject: F.2.2

description: Let $S$ be a finite set of points in the Euclidean plane. Let $D$ be a Delaunay triangulation of $S$. The {\em stretch factor} (also known as {\em dilation} or {\em spanning ratio}) of $D$ is the maximum ratio, among all points $p$ and $q$ in $S$, of the shortest path distance from $p$ to $q$ in $D$ over the Euclidean distance $||pq||$. Proving a tight bound on the stretch factor of the Delaunay triangulation has been a long standing open problem in computational geometry. In this paper we prove that the stretch factor of the Delaunay triangulation of a set of points in the plane is less than $ρ= 1.998$, improving the previous best upper bound of 2.42 by Keil and Gutwin (1989). Our bound 1.998 is better than the current upper bound of 2.33 for the special case when the point set is in convex position by Cui, Kanj and Xia (2009). This upper bound breaks the barrier 2, which is significant because previously no family of plane graphs was known to have a stretch factor guaranteed to be less than 2 on any set of points.
description: 41 pages, 16 figures. A preliminary version of this paper appeared in the Proceedings of the 27th Annual Symposium on Computational Geometry (SoCG 2011). This is a revised version of the previous preprint [v1]
Shot Noise Induced by Nonequilibrium Spin Accumulation
Creators: name: Arakawa, T.
name: Shiogai, Junichi
name: Ciorga, Mariusz
name: Utz, Martin
name: Schuh, Dieter
name: Kohda, M.
name: Nitta, J.
name: Bougeard, Dominique
name: Weiss, Dieter
name: Ono, Teruo
name: Kobayashi, K.
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 530 Physik

description: When an electric current passes across a potential barrier, the partition process of electrons at the barrier gives rise to the shot noise, reflecting the discrete nature of the electric charge. Here we report the observation of excess shot noise connected with a spin current which is induced by a nonequilibrium spin accumulation in an all-semiconductor lateral spin-valve device. We find that this excess shot noise is proportional to the spin current. Additionally, we determine quantitatively the spin-injection-induced electron temperature by measuring the current noise. Our experiments show that spin accumulation driven shot noise provides a novel means of investigating nonequilibrium spin transport.
The Impact of Metallicity on the Rate of Type Ia Supernovae
Creators: name: Kistler, Matthew D.
name: Stanek, K. Z.
name: Kochanek, Christopher S.
name: Prieto, Jose L.
name: Thompson, Todd A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The metallicity of a star strongly affects both its evolution and the properties of the stellar remnant that results from its demise. It is generally accepted that stars with initial masses below ~8 M_sun leave behind white dwarfs and that some sub-population of these lead to Type Ia supernovae. However, it is often tacitly assumed that metallicity has no effect on the rate of SNe Ia. We propose that a consequence of the effects of metallicity is to significantly increase the SN Ia rate in lower-metallicity galaxies, in contrast to previous expectations. This is because lower-metallicity stars leave behind higher-mass white dwarfs, which should be easier to bring to explosion. We first model SN Ia rates in relation to galaxy masses and ages alone, finding that the elevation in the rate of SNe Ia in lower-mass galaxies measured by LOSS is readily explained. However, we then see that models incorporating this effect of metallicity agree just as well. Using the same parameters to estimate the cosmic SN Ia rate, we again find good agreement with data up to z~2. We suggest that this degeneracy warrants more detailed examination of host galaxy metallicities. We discuss additional implications, including for hosts of high-z SNe Ia, the SN Ia delay time distribution, super-Chandrasekhar SNe, and cosmology.
description: 8 pages, 3 figures; updated discussion and added references to agree with published version; conclusions unchanged
Search for B+ -> D+ K0 and B+-> D+ K*0 decays
Creators: name: The BABAR Collaboration
name: Sanchez, P. del Amo
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We report a search for the rare decays $B^+ \to D^+ K^0$ and $B^+ \to D^+ K^{*0}$ in an event sample of approximately 465 million $B\bar B$ pairs collected with the BaBar detector at the PEP-II asymmetric-energy $e^+e^-$ collider at SLAC. We find no significant evidence for either mode and we set 90\% probability upper limits on the branching fractions of $B(B^+ \to D^+ K^0) < 2.9\times 10^{-6}$ and $B(B^+ \to D^+ K^{*0}) < 3.0\times 10^{-6}$.
description: 11 pages, 3 figures, to be submitted to Phys. Rev. D
Surface properties of monolithic zirconia after dental adjustment treats and in vitro wear simulation
Creators: name: Preis, Verena
name: Schmalzbauer, Michael
name: Bougeard, Dominique
name: Schneider-Feyrer, Sibylle
name: Rosentritt, Martin
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: Monolithic zirconia; Adjustment; Polishing; Wear; Roughness; Phase transformation
subject: 530 Physik

description: Objectives To investigate the surface properties (roughness, composition, phase transformation) of monolithic zirconia specimens after dental adjustment procedures (grinding, polishing) and wear simulation. Methods Zirconia specimens (Cercon base, Cercon ht, DeguDent, G; n = 10/material) were successively sintered, ground, and polished with an intraoral polishing kit in a three-step procedure. Sintered zirconia specimens with high surface roughness served as a reference. For each treatment step, wear simulations with steatite plates (d = 10 mm) as antagonists were conducted as well as surface roughness tests (Ra), EDX analysis, and X-ray diffraction (XRD) measurements. SEM pictures were taken, and data were statistically analyzed (one-way ANOVA, post hoc Bonferroni, α = 0.05). Results Grinding significantly (p = 0.000) increased the roughness of sintered zirconia up to values of 1.36 ± 0.11 μm (Ra). Polishing significantly (p = 0.000) reduced Ra. The lowest roughness value after the final polishing step was 0.20 ± 0.03 μm. Wear testing resulted in a further slight decrease of Ra. After the grinding procedure, SEM pictures showed deep grooves that were progressively smoothed by polishing. The EDX spectra showed that magnesium was transferred from steatite antagonists to zirconia by wear. In the XRD-patterns, monoclinic (m) peaks were observed after grinding and polishing. The maximum intensity ratio between the m (1 1 −1) peak and the tetragonal t (1 1 1) peak decreased after the completion of all polishing steps. Wear did not induce phase transformation. Conclusions Adequate polishing reduced the roughness of ground zirconia. Wear had little influence on roughness and no influence on phase transformation. Clinical significance Careful polishing is recommended to keep surface roughness and phase transformation low.
Transborylation: borane-catalysed hydroboration and hidden catalysis
Creators: name: Bage, Andrew Dougal
Publisher: name: The University of Edinburgh
Year: 2022

description: Hydroboration is a textbook reaction, finding application in total synthesis and the fine chemicals industry. The versatility of the organoborane products to be transformed into an array of different functionalities makes the reaction a valuable intermediary in multi-step syntheses. Traditionally, hydroboration was performed using stoichiometric borane reagents, but this was gradually superseded by transition metal-catalysed hydroboration systems. The established metal catalysts are typically based on scarce or expensive transition metals, of which some are toxic. When developing new catalysts for a known transformation, the system must provide a benefit over previous systems, be it through orthogonal reactivity, increased sustainability, or improved chemoselectivity, leading to increased potential to be used in late-stage functionalisation. A potential sustainable alternative to the standard transition metal catalysts is to use a catalyst based upon main-group elements. However, the traditional mechanisms of transition metal catalysis (oxidative addition and reductive elimination) cannot be easily applied to main group catalysts. Therefore, new turnover mechanisms are required to support the development of useful main-group catalysts. Transborylation is a redox-neutral turnover step that transforms stoichiometric borane reagents into catalysts, providing a platform to use the extensive knowledge base of stoichiometric borane reduction to develop new metal-free catalyst systems that could potentially rival transition metal catalysts. Transborylation has been used to develop a borane-catalysed hydroboration of alkynes with HBpin, showing impressive selectivity, and has been used to provide preliminary results for a borane-catalysed enantioselective hydroboration of alkenes. The importance of the hydroboration reaction has resulted in catalysed hydroboration becoming a benchmark with which to test new catalysts. Nucleophiles are abundant in catalyst architectures, as ligands and exogenous activators, and in catalysts that are inherently nucleophilic. Nucleophiles with structural similarities to known hydroboration catalysts were shown to mediate the decomposition of HBpin to active boron-based catalysts, which were the true catalysts of the hydroboration of alkynes and alkenes with HBpin. Hidden boron catalysis was shown to operate in systems for the hydroboration of alkynes and alkenes, previously proposed to be catalysed by nucleophilic catalysts.
Perturbation Resilience and Superiorization of Iterative Algorithms
Creators: name: Censor, Y.
name: Davidi, R.
name: Herman, G. T.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optimization and Control (math.OC)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Medical Physics (physics.med-ph)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Iterative algorithms aimed at solving some problems are discussed. For certain problems, such as finding a common point in the intersection of a finite number of convex sets, there often exist iterative algorithms that impose very little demand on computer resources. For other problems, such as finding that point in the intersection at which the value of a given function is optimal, algorithms tend to need more computer memory and longer execution time. A methodology is presented whose aim is to produce automatically for an iterative algorithm of the first kind a "superiorized version" of it that retains its computational efficiency but nevertheless goes a long way towards solving an optimization problem. This is possible to do if the original algorithm is "perturbation resilient," which is shown to be the case for various projection algorithms for solving the consistent convex feasibility problem. The superiorized versions of such algorithms use perturbations that drive the process in the direction of the optimizer of the given function. After presenting these intuitive ideas in a precise mathematical form, they are illustrated in image reconstruction from projections for two different projection algorithms superiorized for the function whose value is the total variation of the image.
description: Accepted for publication in Inverse Problems, 2010
Large deviation properties of weakly interacting processes via weak convergence methods
Creators: name: Budhiraja, Amarjit
name: Dupuis, Paul
name: Fischer, Markus
Publisher: name: arXiv
Year: 2010
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: We study large deviation properties of systems of weakly interacting particles modeled by Itô stochastic differential equations (SDEs). It is known under certain conditions that the corresponding sequence of empirical measures converges, as the number of particles tends to infinity, to the weak solution of an associated McKean-Vlasov equation. We derive a large deviation principle via the weak convergence approach. The proof, which avoids discretization arguments, is based on a representation theorem, weak convergence and ideas from stochastic optimal control. The method works under rather mild assumptions and also for models described by SDEs not of diffusion type. To illustrate this, we treat the case of SDEs with delay.
description: Published in at http://dx.doi.org/10.1214/10-AOP616 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Temperature-dependent Raman scattering of KTa1-xNbxO3 thin films
Creators: name: Bartasyte, A.
name: Kreisel, J.
name: Peng, W.
name: Guilloux-Viry, M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report a Raman scattering investigation of KTa1-xNbxO3 (x = 0.35, 0.5) thin films deposited on MgO and LaAlO3 as a function of temperature. The observed phase sequence in the range from 90 K to 720 K is similar to the structural phase transitions of the end-member material KNbO3. Although similar in the phase sequence, the actual temperatures observed for phase transition temperatures are significantly different from those observed in the literature for bulk samples. Namely, the tetragonal (ferroelectric) to cubic (paraelectric) phase transition is up to 50 K higher in the films when compared to bulk samples. This enhanced ferroelectricity is attributed to biaxial strain in the investigated thin films.
Learning Generalizable Visual Representations Towards Novel Viewpoints, Scenes and Vocabularies
Creators: name: Zhu, Xiaoyu
Publisher: name: Carnegie Mellon University
Year: 2025
Subjects: classificationCode: 46
subject: Information and computing sciences
classificationCode: 4603
subject: Computer vision and multimedia computation

description: Deep learning has made significant progress to analyze an unprecedented amount of rich visual information from the real world to enable applications such as robotics, surveillance, and public safety monitoring. The successful deployment of deep learning techniques highly relies on the availability of large-scale domain-specific annotated data. However, these constraints are unlikely to be met in many real-world scenarios. In practice, various domain gaps exist between the training and test data. Test data are typically drawn from out-of-domain distributions, encompassing novel viewpoints, varied noise conditions, and diverse scenes. In addition to the diversity in visual representations, deep learning models trained on fixed, closed-set labels may not meet the query requirements of arbitrary text prompts from users. Additionally, novel vocabularies may not be accessible during training. To enable the deployment of a robust visual perception system, learning generalized feature representations during training is crucial. In this thesis, with the goal of developing systems which can generalize to novel viewpoints, scenes and vocabularies, we explore different representation learning methods based on Siamese learning, masked visual modeling, and generatively pretraining. This thesis consists of three parts. The first part conducts robust semantic instance segmentation for videos and 3D data. We aim to learn feature representations that are invariant to various viewpoints and noise conditions via Siamese learning. We propose to leverage temporal consistency for videos and spatial consistency for 3D volumetric images, such that the learned feature representations have strong generalization ability. In the second part, we tackle the problem of human action analysis, which requires the model to learn from dynamic cues. We propose representation learning techniques based on masked visual modeling, such that the model can learn better spatial-temporal context. We also exploit both RGB videos and 3D human meshes for robust multi-modal action analysis. Finally, in the third part, we leverage generatively pre-trained vision-language models and develop systems that can handle novel vocabularies and text prompts. Our final goal is to build a robust system that can generalize to novel viewpoints, scenes, and vocabularies
Cohen-Macaulay approximation in fibred categories
Creators: name: Ile, Runar
Publisher: name: arXiv
Year: 2011
Subjects: subject: Commutative Algebra (math.AC)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 13C60, 14B12 (Primary) 13D02, 18D30 (Secondary)

description: We extend the Auslander-Buchweitz axioms and prove Cohen-Macaulay approximation results for fibred categories. Then we show that these axioms apply for the fibred category of pairs consisting of a finite type flat family of Cohen-Macaulay rings and modules. In particular such a pair admits an approximation with a flat family of maximal Cohen-Macaulay modules and a hull with a flat family of modules with finite injective dimension. The existence of minimal approximations and hulls in the local, flat case implies extension of upper semi-continuous invariants. As an example of MCM approximation we define a relative version of Auslander's fundamental module. In the second part we study the induced maps of deformation functors and deduce properties like injectivity, isomorphism and smoothness under general, mainly cohomological conditions on the module. We also provide deformation theory for pairs (algebra, module), e.g. a cohomology for such pairs, a long exact sequence linking this cohomology to the André-Quillen cohomology of the algebra and the Ext cohomology of the module, Kodaira-Spencer classes and maps including a secondary Kodaira-Spencer class, and existence of a versal family for pairs with isolated singularity.
description: 48 pages. Some minor changes, mainly in the last section. The first part has appeared in J. Algebra 367 (2012) 142-165
Cyclotron-resonance-assisted photon drag effect in InSb/InAlSb quantum wells excited by terahertz radiation
Creators: name: Stachel, Sebastian
name: Budkin, G. V.
name: Hagner, Ursula
name: Belkov, Vassilij
name: Glazov, Mikhail
name: Tarasenko, Sergey
name: Clowes, S. K.
name: Ashley, T.
name: Gilbertson, A. M.
name: Ganichev, Sergey
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: 530 Physik
subject: 72.40.+w
subject: 73.21.Fg
subject: 72.25.Fe
subject: 72.25.Rb

description: We report on the observation of the cyclotron-resonance-assisted photon drag effect. Resonant photocurrent is detected in InSb/InAlSb quantum well structures subject to a static magnetic field and excited by terahertz radiation at oblique incidence. The developed theory based on Boltzmann's kinetic equation is in good agreement with the experimental findings. We show that the resonant photocurrent originates from the transfer of photon momentum to free electrons drastically enhanced at the cyclotron resonance.
Low-​melting mixtures based on choline ionic liquids
Creators: name: Rengstl, Doris
name: Fischer, Veronika
name: Kunz, Werner
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: low melting mixt choline glutarate chloride ionic liq urea choline ionic liq low melting mixt
subject: 540 Chemie

description: A strategy is proposed for the design of low toxic, room temp. liq. low-melting mixts. (LMMs) which are entirely composed of natural materials. From literature it is well known that, in general, deep eutectic solvents based on choline chloride and dicarboxylic acids are LMMs, but not liqs. at room temp., with one exception: a 1:1 M mixt. of malonic acid and choline chloride. Therefore, the starting point of this study was the decrease of the m.p. of one of the components, namely the dicarboxylic acid, which is succinic, glutaric, or adipic acid. For this purpose, one of the two protons of the acidic group was exchanged by a bulky unsym. choline cation. The resulting ionic liqs. (ILs) were still solid at room temp., but have a reduced melting temp. compared with the corresponding acids. In the second step, mixts. of these ILs with choline chloride were prepd. It turned out that choline glutarate-choline chloride mixts. are liqs. at room temp. at compns. contg. 95-98 wt.% of choline glutarate. Finally, urea was added as another hydrogen bond donor. D., cond., and viscosity measurements were performed for all obtained mixts. Moreover, a Walden plot was drawn which indicates that all mixts. are liqs. with fully dissocd. ions moving independently. Therefore, they are considered as "good" ionic liqs. and, thus, for example they can be used to exchange more toxic or less biodegradable ILs in application processes. A brief outlook contg. application possibilities is given. It is demonstrated that choline dodecylsulfate is readily sol. in these mixts., forming aggregates in the LMM at temps. exceeding 55Â°C.
description: Open-Access-Komponente aus der Allianzlizenz
Anomalies in Superfluids and a Chiral Electric Effect
Creators: name: Neiman, Yasha
name: Oz, Yaron
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Superconductivity (cond-mat.supr-con)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We analyze the chiral transport terms in relativistic superfluid hydrodynamics. In addition to the spontaneously broken symmetry current, we consider an arbitrary number of unbroken symmetries and extend the results of arXiv:1105.3733. We suggest an interpretation of some of the new transport coefficients in terms of chiral and gravitational anomalies. In particular, we show that with unbroken gauged charges in the system, one can observe a chiral electric conductivity - a current in a perpendicular direction to the applied electric field. We present a motivated proposal for the value of the associated transport coefficient, linking it to the triangle anomaly. Along the way we present new arguments regarding the interpretation of the anomalous transport coefficients in normal fluids. We propose a natural generalization of the chiral transport terms to the case of an arbitrary number of spontaneously broken symmetry currents.
description: 30 pages; v2: Onsager-relations argument corrected, references added; v3: fixed missing line in eq. (38)
Emergence of surfactant-​free micelles from ternary solutions
Creators: name: Schoettl, Sebastian
name: Marcus, Julien
name: Diat, Oliver
name: Touraud, Didier
name: Kunz, Werner
name: Zemb, Thomas
name: Horinek, Dominik
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: surfactant micelle ternary soln mol dynamics simulation
subject: 540 Chemie

description: Curious effects ranging from enzyme activity to anomalies in evapn. rates that have been known for over fifty years suggest the existence and thermodn. stability of surfactant-free micelles. Only recently, joint X-ray, light and neutron scattering expts. have demonstrated that aggregates and bulk pseudo-phases coexist in presumably normal solns., in which a water insol. component is solubilized in a certain domain of concn. of a hydrotrope component like ethanol. Nevertheless, nothing is known about the mol.-level shape and structure of such aggregates. In this work we characterize mixts. of octanol, ethanol, and water by mol. dynamics simulations. For compns. in the "pre-ouzo" region (close to the single phase stability limit) we observe micelle-like aggregates that are clearly distinct from simple crit. d. fluctuations. We define an ethanol partition in the pseudo-phase from an integral of the van der Waals dispersion energy term. From this partition, octanol-rich aggregates swollen with ethanol appear with an emerging interface. Ethanol is present in the water pseudo-phase with an exponential decay similar to the one predicted by Marcelja and Radic forty years ago.
description: Open-Access-Komponente aus der Allinanzlizenz
New Insights into the Early Stages of Silica-Controlled Barium Carbonate Crystallisation
Creators: name: Eiblmeier, Josef
name: Schürmann, Ulrich
name: Kienle, Lorenz
name: Gebauer, Denis
name: Kunz, Werner
name: Kellermeier, Matthias
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: silica controlled barium carbonate crystn
subject: 540 Chemie

description: Recent work has demonstrated that the dynamic interplay between silica and carbonate during co-pptn. can result in the self-assembly of unusual, highly complex crystal architectures with morphologies and textures resembling those typically displayed by biogenic minerals. These so-called biomorphs were shown to be composed of uniform elongated carbonate nanoparticles that are arranged according to a specific order over mesoscopic scales. In the present study, we have investigated the circumstances leading to the continuous formation and stabilization of such well-defined nanometric building units in these inorg. systems. For this purpose, in situ potentiometric titrn. measurements were carried out in order to monitor and quantify the influence of silica on both the nucleation and early growth stages of barium carbonate crystn. in alk. media at const. pH. Complementarily, the nature and compn. of particles occurring at different times in samples under various conditions were characterised ex situ by means of high-resoln. electron microscopy and elemental anal. The collected data clearly evidence that added silica affects carbonate crystn. from the very beginning (i.e. already prior to, during, and shortly after nucleation), eventually arresting growth on the nanoscale by cementation of BaCO3 particles within a siliceous matrix. Our findings thus shed light on the fundamental processes driving bottom-up self-organization in silica-carbonate materials and, for the first time, provide direct exptl. proof that silicate species are responsible for the miniaturization of carbonate crystals during growth of biomorphs, hence confirming previously discussed theor. models for their formation mechanism.
description: Open-Access-Komponente aus der Allianzlizenz
Social conditioning and extinction paradigm: A translational study in virtual reality
Creators: name: Shiban, Youssef
name: Reichenberger, Jonas
name: Neumann, Inga D.
name: Mühlberger, Andreas
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: social fear conditioning, virtual reality, operant conditioning paradigm, Heart Rate, fear-potentiated startle, social anxiety
subject: 150 Psychologie

description: In human beings, experiments investigating fear conditioning with social stimuli are rare. The current study aims at translating an animal model for social fear conditioning (SFC) to a human sample using an operant SFC paradigm in virtual reality (VR). Forty participants actively (using a joystick) approached virtual male agents that served as conditioned stimuli (CS). During the acquisition phase, unconditioned stimuli (US), a combination of an air blast (5 bar, 10 ms) and a female scream (95 dB, 40 ms), were presented when participants reached a defined proximity to the agent with a contingency of 75% for CS+ agents and never for CS- agents. During the extinction and the test phases, no US was delivered. Outcome variables were pleasantness ratings and physiological reactions in heart rate and fear-potentiated startle. Additionally, the influence of social anxiety, which was measured with the Social Phobia Inventory scale, was evaluated. As expected after the acquisition phase the CS+ was rated clearly less pleasant than the CS-. This difference vanished during extinction. Furthermore, the HR remained high for the CS+, while the HR for the CS- was clearly lower after than before the acquisition. Furthermore, a clear difference between CS+ and CS- after the acquisition indicated successful conditioning on this translational measure. Contrariwise extinction was not observed on the physiological variables. Importantly, at the generalization test, higher socially fearful participants rated pleasantness of all agents as low whereas the lower socially fearful participants rated pleasantness as low only for the CS+. SFC was successfully induced and extinguished confirming operant conditioning in this SFC paradigm. These findings suggest that the paradigm is suitable to expand the knowledge about the learning and unlearning of social fears. Further studies should investigate the operant mechanisms of development and treatment of social anxiety disorder.
An actor prepares (to audition)
Creators: name: Killianey, Michael Andrew
Publisher: name: The University of Texas at Austin
Year: 2004
Subjects: Audition material
Script performance
Monologue

description: This thesis outlines the development of a script for a short performance piece entitled "An Actor Prepares (to Audition)." The piece is approximately twenty minutes long and features the author, a candidate for a Master of Fine Arts degree in acting from the Department of Theatre and Dance at the University of Texas at Austin. This thesis describes the process the author used to select and prepare a body of audition material and contains a script for a performance based on this research
Possible realization of the Exciton Bose Liquid phase in a hard-core boson model with ring-only exchange interactions
Creators: name: Tay, Tiamhock
name: Motrunich, Olexei I.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate a hard-core boson model with ring-only exchanges on a square lattice, where a $K_1$ term acts on 1$\times$1 plaquettes and a $K_2$ term acts on 1$\times$2 and 2$\times$1 plaquettes, with a goal of realizing a novel Exciton Bose Liquid (EBL) phase first proposed by Paramekanti, et al [Phys. Rev. B {\bf 66}, 054526 (2002)]. We construct Jastrow-type variational wave functions for the EBL, study their formal properties, and then use them as seeds for a projective Quantum Monte Carlo study. Using Green's Function Monte Carlo, we obtain an unbiased phase diagram which at half-filling reveals CDW for small $K_2$, valence bond solid for intermediate $K_2$, and possibly for large $K_2$ the EBL phase. Away from half-filling, the EBL phase is present for intermediate $K_2$ and remains stable for a range of densities below 1/2 before phase separation occurs at lower densities.
description: 18 pages, 15 figures