cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A Finite Quantum Gravity Field Theory Model
Creators: name: Alfaro, Jorge
name: González, Pablo
name: Avila, Ricardo
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss the quantization of Delta gravity, a two symmetric tensors model of gravity. This model, in Cosmology, shows accelerated expansion without a cosmological constant. We present the $\tildeδ$ transformation which defines the geometry of the model. Then we show that all delta type models live at one loop only. We apply this to General Relativity and we calculate the one loop divergent part of the Effective Action showing its null contribution in vacuum, implying a finite model. Then we proceed to study the existence of ghosts in the model. Finally, we study the form of the finite quantum corrections to the classical action of the model.
description: Latex, 33 pages
Knowledge organization systems as enablers to the conduct of science
Creators: name: Lambe, Patrick
Publisher: name: Zenodo
Year: 2011
Subjects: subject: knowledge organization systems
subject: KOS
subject: https://iskouk.org/subjects/4OX6PDD7
subject: https://iskouk.org/subjects/PRUIHEDJ

description: The sophistication of knowledge organization systems (KOS) has evolved rapidly over the
 past thirty years, largely driven by information technology innovations. Two key assumptions have been (a) that KOS-work is the preserve of information professionals acting as skilled intermediaries, and (b) that it is largely focused on enabling the finding and discovery of information. This paper challenges both assumptions with reference to the conduct of science in the 21st century, by describing the ways in which access to KOS skills and tools is already broadening beyond information professionals to scientists, and by describing how knowledge organization systems enable sense-making of trends within science and new knowledge creation, beyond simple access and discovery roles. It closes with remarks on the implications for information professionals engaged in KOS-related work.
Efficient Optimization of Performance Measures by Classifier Adaptation
Creators: name: Li, Nan
name: Tsang, Ivor W.
name: Zhou, Zhi-Hua
Publisher: name: arXiv
Year: 2010
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: In practical applications, machine learning algorithms are often needed to learn classifiers that optimize domain specific performance measures. Previously, the research has focused on learning the needed classifier in isolation, yet learning nonlinear classifier for nonlinear and nonsmooth performance measures is still hard. In this paper, rather than learning the needed classifier by optimizing specific performance measure directly, we circumvent this problem by proposing a novel two-step approach called as CAPO, namely to first train nonlinear auxiliary classifiers with existing learning methods, and then to adapt auxiliary classifiers for specific performance measures. In the first step, auxiliary classifiers can be obtained efficiently by taking off-the-shelf learning algorithms. For the second step, we show that the classifier adaptation problem can be reduced to a quadratic program problem, which is similar to linear SVMperf and can be efficiently solved. By exploiting nonlinear auxiliary classifiers, CAPO can generate nonlinear classifier which optimizes a large variety of performance measures including all the performance measure based on the contingency table and AUC, whilst keeping high computational efficiency. Empirical studies show that CAPO is effective and of high computational efficiency, and even it is more efficient than linear SVMperf.
description: 30 pages, 5 figures, to appear in IEEE Transactions on Pattern Analysis and Machine Intelligence, 2012
Diffusion of boron in germanium at 800-900 °C revisited
Creators: name: Kipke, F.
name: Südkamp, T.
name: Prüßing, J. K.
name: Bougeard, Dominique
name: Bracht, H.
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: Diffusion of boron (B) in germanium (Ge) at temperatures ranging between 800∘C and 900∘C is revisited following the most recent results reported by Uppal et al. [J. Appl. Phys. 96, 1376 (2004)] that have been obtained mainly with implantation doped samples. In this work, we determined the intrinsic B diffusivity by employing epitaxially grown alternating undoped and B-doped Ge layer structures with three different dopant concentrations of 4×1017 cm−3, 1×1018 cm−3, and 3×1018 cm−3. The diffusional broadening of B was analyzed by means of secondary ion mass spectrometry (SIMS) and numerically described to determine the diffusion coefficient. Additional SIMS analyses revealed a gradient in the oxygen (O) background concentration of the epitaxially doped Ge structure. A high O content observed in near-surface regions correlates with enhanced B diffusion. In contrast, B-doped regions with low O content showed a significantly lower B diffusivity representing the intrinsic diffusivity. The B diffusion coefficients are significantly lower compared to literature data and best described by a diffusion activation enthalpy and a pre-exponential factor of (4.09±0.21) eV and 265+2256−237 cm2 s−1, respectively.
Design of coupling for synchronization in time-delayed systems
Creators: name: Ghosh, Dibakar
name: Grosu, Ioan
name: Dana, Syamal Kumar
Publisher: name: arXiv
Year: 2011
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We report a design of delay coupling for targeting desired synchronization in delay dynamical systems. We target synchronization, antisynchronization, lag-, antilag- synchronization, amplitude death (or oscillation death) and generalized synchronization in mismatched oscillators. A scaling of the size of an attractor is made possible in different synchronization regimes. We realize a type of mixed synchronization where synchronization, antisynchronization coexist in different pairs of state variables of the coupled system. We establish the stability condition of synchronization using the Krasovskii-Lyapunov function theory and the Hurwitz matrix criterion. We present numerical examples using the Mackey-Glass system and a delay Rössler system.
description: 8 pages, 6 figures; Chaos 22 (2012)
Crowdsourcing and Aggregating Nested Markable Annotations
Creators: name: Madge, Chris
name: Yu, Juntao
name: Chamberlain, Jon
name: Kruschwitz, Udo
name: Paun, Silviu
name: Poesio, Massimo
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 020 Bibliotheks- und Informationswissenschaft

description: One of the key steps in language resource creation is the identification of the text segments to be annotated, or markables, which depending on the task may vary from nominal chunks for named entity resolution to (potentially nested) noun phrases in coreference resolution (or mentions) to larger text segments in text segmentation. Markable identification is typically carried out semi-automatically, by running a markable identifier and correcting its output by hand—which is increasingly done via annotators recruited through crowdsourcing and aggregating their responses. In this paper, we present a method for identifying markables for coreference annotation that combines high-performance automatic markable detectors with checking with a Game-With-A-Purpose (GWAP) and aggregation using a Bayesian annotation model. The method was evaluated both on news data and data from a variety of other genres and results in an improvement on F1 of mention boundaries of over seven percentage points when compared with a state-of-the-art, domain-independent automatic mention detector, and almost three points over an in-domain mention detector. One of the key contributions of our proposal is its applicability to the case in which markables are nested, as is the case with coreference markables; but the GWAP and several of the proposed markable detectors are task and language-independent and are thus applicable to a variety of other annotation scenarios.
Gold-linked strings of donor–acceptor dyads: on-surface formation and mutual orientation
Creators: name: Karan, Sujoy
name: Geng, Yan
name: Decurtins, Silvio
name: Liu, Shi-Xia
name: Repp, Jascha
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik
subject: 540 Chemie

description: Strings of gold-organic oligomers of polar units have been formed by on-surface synthesis and investigated with non-contact atomic force microscopy. The mutual alignment of dipoles within the strings is analyzed. While an alternating head-to-tail alignment might be expected from dipolar interactions, a more complicated alignment order is observed. The data suggests that coordination bonding to additional gold adatoms leads to stabilization of parallel pairs of molecules, suppressing a head-to-tail alignment order.
Supersymmetric Surface Operators, Four-Manifold Theory and Invariants in Various Dimensions
Creators: name: Tan, Meng-Chwan
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Differential Geometry (math.DG)
subject: Geometric Topology (math.GT)
subject: Symplectic Geometry (math.SG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We continue our program initiated in [arXiv:0912.4261] to consider supersymmetric surface operators in a topologically-twisted N=2 pure SU(2) gauge theory, and apply them to the study of four-manifolds and related invariants. Elegant physical proofs of various seminal theorems in four-manifold theory obtained by Ozsvath-Szabo [2,3] and Taubes [4], will be furnished. In particular, we will show that Taubes' groundbreaking and difficult result -- that the ordinary Seiberg-Witten invariants are in fact the Gromov invariants which count pseudo-holomorphic curves embedded in a symplectic four-manifold X -- nonetheless lends itself to a simple and concrete physical derivation in the presence of "ordinary" surface operators. As an offshoot, we will be led to several interesting and mathematically novel identities among the Gromov and "ramified" Seiberg-Witten invariants of X, which in certain cases, also involve the instanton and monopole Floer homologies of its three-submanifold. Via these identities, and a physical formulation of the "ramified" Donaldson invariants of four-manifolds with boundaries, we will uncover completely new and economical ways of deriving and understanding various important mathematical results concerning (i) knot homology groups from "ramified" instantons by Kronheimer-Mrowka [5]; and (ii) monopole Floer homology and Seiberg-Witten theory on symplectic four-manifolds by Kutluhan-Taubes [4,6]. Supersymmetry, as well as other physical concepts such as R-invariance, electric-magnetic duality, spontaneous gauge symmetry-breaking and localization onto supersymmetric configurations in topologically-twisted quantum field theories, play a pivotal role in our story.
description: 58 pages. Minor refinement and details of references updated. Published version
Comparative analyses of caste, sex, and developmental stage‐specific transcriptomes in two Temnothorax ants
Creators: name: Gstöttl, Claudia
name: Stoldt, Marah
name: Jongepier, Evelien
name: Bornberg‐Bauer, Erich
name: Feldmeyer, Barbara
name: Heinze, Jürgen
name: Foitzik, Susanne
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: caste, developmental stages, gene expression, slave-making ants, transcriptomics
subject: 590 Tiere (Zoologie)

description: Social insects dominate arthropod communities worldwide due to cooperation and division of labor in their societies. This, however, makes them vulnerable to exploitation by social parasites, such as slave‐making ants. Slave‐making ant workers pillage brood from neighboring nests of related host ant species. After emergence, host workers take over all nonreproductive colony tasks, whereas slavemakers have lost the ability to care for themselves and their offspring. Here, we compared transcriptomes of different developmental stages (larvae, pupae, and adults), castes (queens and workers), and sexes of two related ant species, the slavemaker Temnothorax americanus and its host Temnothorax longispinosus. Our aim was to investigate commonalities and differences in group‐specific transcriptomes, whereupon across‐species differences possibly can be explained by their divergent lifestyles. Larvae and pupae showed the highest similarity between the two species and upregulated genes with enriched functions of translation and chitin metabolism, respectively. Workers commonly upregulated oxidation‐reduction genes, possibly indicative of their active lifestyle. Host workers, but not workers of the slavemaker, upregulated a “social behavior” gene. In slavemaker queens and workers, genes associated with the regulation of transposable elements were upregulated. Queens of both species showed transcriptomic signals of anti‐aging mechanisms, with hosts upregulating various DNA repair pathways and slavemaker queens investing in trehalose metabolism. The transcriptomes of males showed enriched functions for quite general terms realized in different genes and pathways in each species. In summary, the strong interspecific commonalities in larvae, pupae, and workers were reflected in the same enriched Gene Ontology (GO) terms. Less commonalities occurred in the transcriptomes of queens and males, which apparently utilize different pathways to achieve a long life and sperm production, respectively. We found that all analyzed groups in this study show characteristic GO terms, with similar patterns in both species.
Paclitaxel, Imatinib and 5-Fluorouracil Increase the Unbound Fraction of Flucloxacillin In Vitro
Creators: name: Stolte, Maximilian
name: Ali, Weaam
name: Jänis, Janne
name: Gessner, Andre
name: El-Najjar, Nahed
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: albumin; α-1-acid glycoprotein; drug-drug interactions; anti-infective agents; ultrafiltration; cancer
subject: 610 Medizin

description: Flucloxacillin (FLU), an isoxazolyl penicillin, is widely used for the treatment of different bacterial infections in intensive care units (ICU). Being highly bound to plasma proteins, FLU is prone to drug-drug interactions (DDI) when administered concurrently with other drugs. As FLU is binding to both Sudlow’s site I and site II of human serum albumin (HSA), competitive and allosteric interactions with other drugs, highly bound to the same sites, seem conceivable. Knowledge about interaction(s) of FLU with the widely used anticancer agents paclitaxel (PAC), imatinib (IMA), and 5-fluorouracil (5-FU is scarce. The effects of the selected anticancer agents on the unbound fraction of FLU were evaluated in pooled plasma as well as in HSA and α-1-acid glycoprotein (AGP) samples, the second major drug carrier in plasma. FLU levels in spiked samples were analyzed by LC-MS/MS after ultrafiltration. Significant increase in FLU unbound fraction was observed when in combination with PAC and IMA and to a lesser extent with 5-FU. Furthermore, significant binding of FLU to AGP was observed. Collectively, this is the first study showing the binding of FLU to AGP as well as demonstrating a significant DDI between PAC/IMA/5-FU and FLU.
High Order Coherent Control Sequences of Finite-Width Pulses
Creators: name: Pasini, S.
name: Karbach, P.
name: Uhrig, G. S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The performance of sequences of designed pulses of finite length $τ$ is analyzed for a bath of spins and it is compared with that of sequences of ideal, instantaneous pulses. The degree of the design of the pulse strongly affects the performance of the sequences. Non-equidistant, adapted sequences of pulses, which equal instantaneous ones up to $\mathcal{O}(τ^3)$, outperform equidistant or concatenated sequences. Moreover, they do so at low energy cost which grows only logarithmically with the number of pulses, in contrast to standard pulses with linear growth.
description: 6 pages, 5 figures, new figures, published version
Acquired resistance to DZNep-mediated apoptosis is associated with copy number gains of AHCY in a B-cell lymphoma model
Creators: name: Akpa, C. A.
name: Kleo, K.
name: Oker, E.
name: Tomaszewski, N.
name: Messerschmidt, C.
name: López, C.
name: Wagener, R.
name: Oehl-Huber, K.
name: Dettmer, Katja
name: Schoeler, A.
name: Lenze, D.
name: Oefner, Peter J.
name: Beule, D.
name: Siebert, R.
name: Capper, D.
name: Dimitrova, L.
name: Hummel, M.
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 3- Deazaneplanocin a (DZNep); B-cell lymphoma; Enhancer of zeste homolog 2 (EZH2); S-adenosyl-L-homocysteine hydrolase (AHCY)
subject: 610 Medizin

description: BACKGROUND: Enhancer of zeste homolog 2 (EZH2) is considered an important driver of tumor development and progression by its histone modifying capabilities. Inhibition of EZH2 activity is thought to be a potent treatment option for eligible cancer patients with an aberrant EZH2 expression profile, thus the indirect EZH2 inhibitor 3-Deazaneplanocin A (DZNep) is currently under evaluation for its clinical utility. Although DZNep blocks proliferation and induces apoptosis in different tumor types including lymphomas, acquired resistance to DZNep may limit its clinical application. METHODS: To investigate possible mechanisms of acquired DZNep resistance in B-cell lymphomas, we generated a DZNep-resistant clone from a previously DZNep-sensitive B-cell lymphoma cell line by long-term treatment with increasing concentrations of DZNep (ranging from 200 to 2000 nM) and compared the molecular profiles of resistant and wild-type clones. This comparison was done using molecular techniques such as flow cytometry, copy number variation assay (OncoScan and TaqMan assays), fluorescence in situ hybridization, Western blot, immunohistochemistry and metabolomics analysis. RESULTS: Whole exome sequencing did not indicate the acquisition of biologically meaningful single nucleotide variants. Analysis of copy number alterations, however, demonstrated among other acquired imbalances an amplification (about 30 times) of the S-adenosyl-L-homocysteine hydrolase (AHCY) gene in the resistant clone. AHCY is a direct target of DZNep and is critically involved in the biological methylation process, where it catalyzes the reversible hydrolysis of S-adenosyl-L-homocysteine to L-homocysteine and adenosine. The amplification of the AHCY gene is paralleled by strong overexpression of AHCY at both the transcriptional and protein level, and persists upon culturing the resistant clone in a DZNep-free medium. CONCLUSIONS: This study reveals one possible molecular mechanism how B-cell lymphomas can acquire resistance to DZNep, and proposes AHCY as a potential biomarker for investigation during the administration of EZH2-targeted therapy with DZNep.
Role of hyperfine interaction for cavity-mediated coupling between spin qubits
Creators: name: Hildmann, Julia
name: Burkard, Guido
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Other Condensed Matter (cond-mat.other)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We consider two qubits interacting by means of an optical cavity, where each qubit is represented by a single electron spin confined to a quantum dot. It is known that electron spins in III-V semiconductor quantum dots are affected by the decoherence due to the hyperfine interaction with nuclear spins. Here we show that the interaction between two qubits is influenced by the Overhauser field as well. Starting from an unpolarizied nuclear ensemble, we investigate the dependance of the fidelities for two-qubit gates on the Overhauser field. We include the hyperfine interaction perturbatively to second order in our analytical results, and to arbitrary precision numerically.
description: 7 pages, 7 figures
Video Tutorial for Indocyanine Green Lymphography in Lymphatic Surgery
Creators: name: Klingelhoefer, Eric
name: Schiltz, Daniel
name: Ranieri, Marco
name: Baringer, Magnus
name: Heidekrueger, Paul I.
name: Forte, Antonio J.
name: Prantl, Lukas
name: Brebant, Vanessa
name: Aung, Thiha
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 570 Biowissenschaften, Biologie

description: An accurate diagnosis for patients with lymphedema is crucial for treatment and surgical management. Lymphedema can be diagnosed with medical history, a physical exam, limb measurements, and medical imaging.1,2 There are many methods to evaluate lymphedema such as circumference measurements, volumetry, lymphoscintigraphy (LS), computed tomography, photon emission computed tomography, magnetic resonance imaging (MRI), MRI lymphangiography, and indocyanine green (ICG) lymphography.3–11 ICG is a fluorescent cyanine dye that remains within the blood and lymphatic vessels due to its high rate of binding to plasma proteins and therefore low extravasation rates. Thus, ICG is ideal for visualizing superficial lymphatic vessels when stimulated with fluorescent and laser light. ICG lymphography has a unique ability in demonstrating the structural disorders of lymph nodes, and it has a high accuracy in evaluating lymphedemas and lymphatic flow disorders.12 Mihara et al. found that MRI and ICG lymphography were superior to LS or computed tomography for the diagnosis of lymphedema. They suggest dual diagnosis by examination of the lymphatic system using ICG lymphography and evaluation of edema in subcutaneous fat tissue using MRI. Furthermore, Mihara et al. showed that ICG lymphography is superior to LS for diagnostic imaging of early lymphedema of the upper limbs.
Modeling Latent Non-Linear Dynamical System over Time Series
Creators: name: Fujiwara, Ren
name: Matsubara, Yasuko
name: Sakurai, Yasushi
Publisher: name: arXiv
Year: 2024
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: We study the problem of modeling a non-linear dynamical system when given a time series by deriving equations directly from the data. Despite the fact that time series data are given as input, models for dynamics and estimation algorithms that incorporate long-term temporal dependencies are largely absent from existing studies. In this paper, we introduce a latent state to allow time-dependent modeling and formulate this problem as a dynamics estimation problem in latent states. We face multiple technical challenges, including (1) modeling latent non-linear dynamics and (2) solving circular dependencies caused by the presence of latent states. To tackle these challenging problems, we propose a new method, Latent Non-Linear equation modeling (LaNoLem), that can model a latent non-linear dynamical system and a novel alternating minimization algorithm for effectively estimating latent states and model parameters. In addition, we introduce criteria to control model complexity without human intervention. Compared with the state-of-the-art model, LaNoLem achieves competitive performance for estimating dynamics while outperforming other methods in prediction.
description: Accepted by AAAI'25
An explicit formula for the Berezin star product
Creators: name: Xu, Hao
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Algebra (math.QA)
subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We prove an explicit formula of the Berezin star product on Kaehler manifolds. The formula is expressed as a summation over certain strongly connected digraphs. The proof relies on a combinatorial interpretation of Englis' work on the asymptotic expansion of the Laplace integral.
description: 19 pages, to appear in Lett. Math. Phys
Microwave-assisted biginelli reaction: An old reaction, a new perspective
Creators: name: Mommahed Heravi, Majid
name: Ghavidel, Mahdieh
name: Heidari, Bahareh
Publisher: name: figshare
Year: 2022
Subjects: subject: 30302 Nanochemistry and Supramolecular Chemistry
subject: FOS: Chemical sciences
subject: 30701 Quantum Chemistry
subject: 39904 Organometallic Chemistry
subject: Organic Chemistry
subject: 30502 Natural Products Chemistry
subject: 30599 Organic Chemistry not elsewhere classified
subject: 30205 Non-metal Chemistry
subject: Nuclear Chemistry
subject: 30504 Organic Green Chemistry
subject: 30303 Optical Properties of Materials

description: In this review, we tried to highlight the recent advances in the Biginelli reaction, leading to the synthesis of 3,4-dihydropyrimidin-2(1H)-ones, albeit only those conducted under microwave irradiation. The merits and drawbacks of these reactions are compared and discussed with those performed under conventional heating.
An Efficient Industrial Robot Calibrator With Multiplaner Constraints
Creators: name: Luo, Xin
name: Yang, Weiyi
name: Chen, Tinghui
name: Zhang, Zhetao
Publisher: name: Institute of Electrical and Electronics Engineers (IEEE)
Year: 2024

description: Calibration technology has become an essential part of the task of improving robot precision. However, existing calibration schemes suffer from accuracy loss in actual working conditions due to the ignorance of the target robot's constrained workspace. In response to this challenge, this study proposes a novel robot calibrator with three-fold ideas: 1) optimizing the measurement configuration via the measurement configurations selection (MCS) for suppressing the measurement noises, 2) developing the alternation-direction-method-of-multipliers with multiplanar constraints (AMPC) algorithm for superior calibration accuracy and mitigatory long-tail convergence, with its convergence being theoretically proved, and 3) building the MCS-AMPC-based robot calibrator for efficient kinematic parameters calibration. For validating its performance, the HRS-P dataset that contains 2400 samples collected from different working spaces of an HRS-JR680 industrial robot has been established and publicly released. Empirical studies conclusively affirm that, compared to the Levenberg–Marquardt algorithm (the most accurate among several state-of-the-art algorithms), the proposed AMPC algorithm reduces the mean error by 10.34%. After denoising the calibration data with MCS and then employing the AMPC algorithm to identify the robot's kinematic parameters, the calibration accuracy can be further improved. Moreover, building an ensemble to address the issue of various local optimal solutions can also contribute to better calibration accuracy. The empirical results highlight the superiority and scalability of the MCS-AMPC calibrator for industrial robot-related applications.
Mechanisms governing the pioneering and redistribution capabilities of the non-classical pioneer PU.1
Creators: name: Minderjahn, Julia
name: Schmidt, Andreas
name: Fuchs, Andreas
name: Schill, Rudolf
name: Raithel, Johanna
name: Babina, Magda
name: Schmidl, C.
name: Gebhard, Claudia
name: Schmidhofer, Sandra
name: Mendes, Karina
name: Ratermann, Anna
name: Glatz, Dagmar
name: Nützel, Margit
name: Edinger, Matthias
name: Hoffmann, Petra
name: Spang, Rainer
name: Längst, Gernot
name: Imhof, A.
name: Rehli, Michael
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 610 Medizin

description: Establishing gene regulatory networks during differentiation or reprogramming requires master or pioneer transcription factors (TFs) such as PU.1, a prototype master TF of hematopoietic lineage differentiation. To systematically determine molecular features that control its activity, here we analyze DNA-binding in vitro and genome-wide in vivo across different cell types with native or ectopic PU.1 expression. Although PU.1, in contrast to classical pioneer factors, is unable to access nucleosomal target sites in vitro, ectopic induction of PU.1 leads to the extensive remodeling of chromatin and redistribution of partner TFs. De novo chromatin access, stable binding, and redistribution of partner TFs both require PU.1's N-terminal acidic activation domain and its ability to recruit SWI/SNF remodeling complexes, suggesting that the latter may collect and distribute co-associated TFs in conjunction with the non-classical pioneer TF PU.1.
Partial vision : remediations of the Algerian veil in film and scholarship after Fanon
Creators: name: Ullrich, Madeline
Publisher: name: University of British Columbia
Year: 2018

description: This thesis takes up the Algerian haik (veil), and more specifically how the process of veiling and unveiling first described by the Martinican-born psychiatrist Frantz Fanon, have been depicted in film. Scholars repeatedly associate Fanon’s famous essay “Algeria Unveiled” (1959)—which considers the role of the veiled Algerian woman in the revolutionary struggle—to Gillo Pontecorvo’s equally prominent neo-realist film The Battle of Algiers (1966), where the veil plays a prominent role in allowing the Algerian woman to carry bombs undetected. Similarly, an allusion to the Algerian woman and the veil appears in the documentary Images of the World and the Inscription of War (1989), directed by avant-garde filmmaker Harun Farocki, where the director shows photographs of women unveiled during the war by French soldiers. Previous scholars have compared the women in this film to those in The Battle of Algiers, and by extension, those described by Fanon in his essay. Rather than reading the veil through lenses of “the gaze” or Orientalism, the two dominant discourses applied to these films, the interpretation I provide synthesizes two concepts from media theory, specifically theories of cultural techniques and remediation. I argue that the dynamic operation of veiling and unveiling, a cultural technique that produces gendered and colonial difference, is what lends the veil to remediation, as Fanon’s argument and the process of veiling and unveiling are visualized in cinema. Viewing these films as examples of the veil through layers of remediation—from Fanon’s critical essay to Pontecorvo’s dramatic film to photographs to Farocki’s experimental documentary—the cultural technique of veiling disrupts the binaries—such as gender—it seems to impose. The very process of veiling and unveiling itself complicates a stable reading of both the veil and the Algerian woman.
Comparing large lecture mechanics curricula using the Force Concept Inventory: A five thousand student study
Creators: name: Caballero, Marcos D.
name: Kohlmyer, Matthew A.
name: Greco, Edwin F.
name: Murray, Eric R.
name: Bujak, Keith R.
name: Marr, M. Jackson
name: Catrambone, Richard
name: Schatz, Michael F.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: The performance of over 5000 students in introductory calculus-based mechanics courses at the Georgia Institute of Technology was assessed using the Force Concept Inventory (FCI). Results from two different curricula were compared: a traditional mechanics curriculum and the Matter & Interactions (M&I) curriculum. Post-instruction FCI averages were significantly higher for the traditional curriculum than for the M&I curriculum; the differences between curricula persist after accounting for factors such as pre-instruction FCI scores, grade point averages, and SAT scores. FCI performance on categories of items organized by concepts was also compared; traditional averages were significantly higher in each concept. We examined differences in student preparation between the curricula and found that the relative fraction of homework and lecture topics devoted to FCI force and motion concepts correlated with the observed performance differences. Limitations of concept inventories as instruments for evaluating curricular reforms are discussed.
description: 21 pages, 4 figures, submitted to Am. J. Phys. arXiv admin note: substantial text overlap with arXiv:1112.5593
Floquet oscillations in periodically driven Dirac systems
Creators: name: Junk, Vanessa
name: Reck, Phillipp
name: Gorini, Cosimo
name: Richter, Klaus
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: Floquet, Bloch, Floquet-Bloch oscillations, time periodic systems
subject: 530 Physik

description: Electrons in a lattice exhibit time-periodic motion, known as Bloch oscillation, when subject to an additional static electric field. Here, we show that a corresponding dynamics can occur upon replacing the spatially periodic potential by a time-periodic driving: Floquet oscillations of charge carriers in a spatially homogeneous system. The time lattice of the driving gives rise to Floquet bands that take on the role of the usual Bloch bands. For two different drivings (harmonic driving and periodic kicking through pulses) of systems with linear dispersion we demonstrate the existence of such oscillations, both by directly propagating wave packets and based on a complementary Floquet analysis. The Floquet oscillations feature richer oscillation patterns than their Bloch counterpart and enable the imaging of Floquet bands. Moreover, their period can be directly tuned through the driving frequency. Such oscillations should be experimentally observable in effective Dirac systems, such as graphene, when illuminated with circularly polarized light.
Micronutrients and Diets in the Treatment of Attention-Deficit/Hyperactivity Disorder: Chances and Pitfalls
Creators: name: Lange, Klaus W.
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: attention-deficit/hyperactivity disorder, micronutrients, diet, lifestyle, treatment
subject: 150 Psychologie

description: Attention-deficit/hyperactivity disorder (ADHD) is one of the most common psychiatric diagnoses in childhood and adolescence. It is characterized by age-inappropriate levels of inattention, impulsivity, and hyperactivity and is associated with long-term academic, social, and mental health problems (1, 2). Both pharmacotherapy and behavior therapy yield short-term symptom reduction in individuals with ADHD. Psychostimulants, in particular, have been shown to improve attention and to decrease activity levels in children in the short term. However, their impact on academic performance and quality of life is low (3, 4), and initial symptomatic effects are not usually sustained on long-term follow-up (5, 6). The unproven long-term efficacy of commonly used ADHD drugs, together with concerns in regard to adverse effects of medication, which can be as serious as growth retardation and severe cardiovascular events (7, 8), has led to a search for alternative treatment options.
A Constrained ICA-EMD Model for Group Level fMRI Analysis
Creators: name: Wein, Simon
name: Tomé, Ana M.
name: Goldhacker, Markus
name: Greenlee, Mark W.
name: Lang, Elmar W.
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: independent component analysis, ICA, empirical mode decomposition, EMD, Green’s-function - based EMD, fMRI
subject: 150 Psychologie

description: Independent component analysis (ICA), being a data-driven method, has been shown to be a powerful tool for functional magnetic resonance imaging (fMRI) data analysis. One drawback of this multivariate approach is that it is not, in general, compatible with the analysis of group data. Various techniques have been proposed to overcome this limitation of ICA. In this paper, a novel ICA-based workflow for extracting resting-state networks from fMRI group studies is proposed. An empirical mode decomposition (EMD) is used, in a data-driven manner, to generate reference signals that can be incorporated into a constrained version of ICA (cICA), thereby eliminating the inherent ambiguities of ICA. The results of the proposed workflow are then compared to those obtained by a widely used group ICA approach for fMRI analysis. In this study, we demonstrate that intrinsic modes, extracted by EMD, are suitable to serve as references for cICA. This approach yields typical resting-state patterns that are consistent over subjects. By introducing these reference signals into the ICA, our processing pipeline yields comparable activity patterns across subjects in a mathematically transparent manner. Our approach provides a user-friendly tool to adjust the trade-off between a high similarity across subjects and preserving individual subject features of the independent components.
Infinitely divisible central probability measures on compact Lie groups---regularity, semigroups and transition kernels
Creators: name: Applebaum, David
Publisher: name: arXiv
Year: 2010
Subjects: subject: Probability (math.PR)
subject: Functional Analysis (math.FA)
subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: We introduce a class of central symmetric infinitely divisible probability measures on compact Lie groups by lifting the characteristic exponent from the real line via the Casimir operator. The class includes Gauss, Laplace and stable-type measures. We find conditions for such a measure to have a smooth density and give examples. The Hunt semigroup and generator of convolution semigroups of measures are represented as pseudo-differential operators. For sufficiently regular convolution semigroups, the transition kernel has a tractable Fourier expansion and the density at the neutral element may be expressed as the trace of the Hunt semigroup. We compute the short time asymptotics of the density at the neutral element for the Cauchy distribution on the $d$-torus, on SU(2) and on SO(3), where we find markedly different behaviour than is the case for the usual heat kernel.
description: Published in at http://dx.doi.org/10.1214/10-AOP604 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Incidence of Anaplastic Large Cell Lymphoma and Breast-Implant-Associated Lymphoma—An Analysis of a Certified Tumor Registry over 17 Years
Creators: name: Prantl, Lukas
name: Gerken, Michael
name: Zeman, Florian
name: Leitzmann, Michael
name: Koller, Michael
name: Klinkhammer-Schalke, Monika
name: Evert, Matthias
name: Kuehlmann, Britta
name: Biermann, Niklas
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: anaplastic large cell lymphoma; CD-30 positive; ALK-negative; breast implants; incidence
subject: 610 Medizin

description: Background: Breast-implant-associated anaplastic large cell lymphoma (BI-ALCL) and primary breast ALCL are rare extranodal manifestations of non-Hodgkin lymphoma. The rarity of both diseases, along with unreleased sales data on breast implants and constant updates of classification systems impede the calculation of an exact incidence. Methods: The database of the Tumor Center Regensburg in Bavaria was searched for patients with CD30-positive and ALK-negative anaplastic large cell lymphoma between 2002 and 2018. These lymphomas were identified by the ICD-O-3 morphology code “97023” and were cross-checked by searching the diagnosis by name the and ICD-10 code C84.7. Furthermore, we tried to calculate the incidence rates and corresponding 95% confidence intervals, standardized to 1,000,000 implant years of breast-implant-associated anaplastic large cell lymphoma and primary breast anaplastic large cell lymphoma. Results: Twelve ALK-negative and CD30-positive anaplastic large cell lymphomas were identified out of 170,405 malignancies. No case was found within the breast tissue and none of the patients had a previous history of breast implant placement. In five cases, lymph node involvement in close proximity to the breast was observed. Conclusion: We found a low incidence of anaplastic large cell lymphoma and no association to breast implants in these patients. A review of the current literature revealed inconsistent use of classification systems for anaplastic large cell lymphomas and potential overestimation of cases.
Fluctuation-induced forces between inclusions in a fluid membrane under tension
Creators: name: Lin, Hsiang-Ku
name: Zandi, Roya
name: Mohideen, Umar
name: Pryadko, Leonid P.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We discuss the fluctuation-induced force, a finite-temperature analog of the Casimir force, between two inclusions embedded in a fluid membrane under tension. We suggest a method to calculate this Casimir interaction in the most general case, where membrane fluctuations are governed by the combined action of surface tension, bending modulus, and the Gaussian rigidity. We find that the surface tension strongly modifies the power law in the separation dependence of the Casimir interaction. This results in a strong suppression of the Casimir force at separations beyond a characteristic length, which could affect protein aggregation dynamics in cell membranes.
description: 4 pages, 1 figure
Phase diagram for the $ν=0$ quantum Hall state in monolayer graphene
Creators: name: Kharitonov, Maxim
Publisher: name: arXiv
Year: 2011
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The $ν=0$ quantum Hall state in a defect-free graphene sample is studied within the framework of quantum Hall ferromagnetism. We perform a systematic analysis of the pseudospin anisotropies, which arise from the valley and sublattice asymmetric short-range electron-electron (e-e) and electron-phonon (e-ph) interactions. The phase diagram, obtained in the presence of generic pseudospin anisotropy and the Zeeman effect, consists of four phases characterized by the following orders: spin-polarized ferromagnetic, canted antiferromagnetic, charge density wave, and Kekulé distortion. We take into account the Landau level mixing effects and show that they result in the key renormalizations of parameters. First, the absolute values of the anisotropy energies become greatly enhanced and can significantly exceed the Zeeman energy. Second, the signs of the anisotropy energies due to e-e interactions can change upon renormalization. A crucial consequence of the latter is that the short-range e-e interactions alone could favor any state on the phase diagram, depending on the details of interactions at the lattice scale. On the other hand, the leading e-ph interactions always favor the Kekulé distortion order. The possibility of inducing phase transitions by tilting the magnetic field is discussed.
description: 25 pages, 19 figs; v2: nearly identical to the published version, some stylistic improvements, Tables I-IV added, anisotropy energies redefined as u -> u/2 for aesthetic reason
Umpolung Difunctionalization of Carbonyls via Visible-Light Photoredox Catalytic Radical-Carbanion Relay
Creators: name: Wang, Shun
name: Cheng, Bei-Yi
name: Sršen, Matea
name: König, Burkhard
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 540 Chemie

description: The combination of photoredox catalysis with the Wolff−Kishner (WK) reaction allows the difunctionalization of carbonyl groupsby a radical-carbanion relay sequence (photo-Wolff−Kishner reaction).Photoredox initiated radical addition toN-sulfonylhydrazones yieldsα-functionalized carbanions following the WK-type mechanism. Withsulfur-centered radicals, the carbanions are further functionalized byreaction with electrophiles including CO2and aldehydes, whereas CF3radical addition furnishes a wide range ofgem-difluoroalkenes throughβ-fluoride elimination of the generatedα-CF3carbanions. More than 80substrate examples demonstrate the broad applicability of this reactionsequence. A series of investigations including radical inhibition,deuterium labeling,fluorescence quenching, cyclic voltammetry, andcontrol experiments support the proposed radical-carbanion relay mechanism.
Scanning Electrochemical Microscopy of Electrically Heated Wire Substrates
Creators: name: Wert, Stefan
name: Fußstetter, Alexander
name: Iffelsberger, Christian
name: Matysik, Frank-Michael
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: hot-wire electrochemistry; scanning electrochemical microscopy; SECM; heated electrodes
subject: 540 Chemie

description: We report a new configuration for enhancing the performance of scanning electrochemical microscopy (SECM) via heating of the substrate electrode. A flattened Pt microwire was employed as the substrate electrode. The substrate was heated by an alternating current (AC), resulting in an increased mass transfer between the wire surface and the bulk solution. The electrochemical response of the Pt wire during heating was investigated by means of cyclic voltammetry (CV). The open circuit potential (OCP) of the wire was recorded over time, while varied heating currents were applied to investigate the time needed for establishing steady-state conditions. Diffusion layer studies were carried out by performing probe approach curves (PACs) for various measuring modes of SECM. Finally, imaging studies of a heated substrate electrode surface, applying feedback, substrate generation/tip collection (SG/TC), and the competition mode of SECM, were performed and compared with room temperature results.
The probability distributions of the first hitting times of Bessel processes
Creators: name: Hamana, Yuji
name: Matsumoto, Hiroyuki
Publisher: name: arXiv
Year: 2011
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60J60 (primary) 33C10, 44A10 (secondary)

description: We consider the first hitting times of the Bessel processes. We give explicit expressions for the distribution functions and for the densities by means of the zeros of the Bessel functions. The results extend the classical ones and cover all the cases.
description: 23 pages
Linezolid Concentrations in Plasma and Subcutaneous Tissue are Reduced in Obese Patients, Resulting in a Higher Risk of Underdosing in Critically Ill Patients: A Controlled Clinical Pharmacokinetic Study
Creators: name: Simon, Philipp
name: Busse, David
name: Petroff, David
name: Dorn, Christoph
name: Ehmann, Lisa
name: Hochstädt, Sophie
name: Girrbach, Felix
name: Dietrich, Arne
name: Zeitlinger, Markus
name: Kees, Frieder
name: Kloft, Charlotte
name: Wrigge, Hermann
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: antibiotic dosing; concentrations; linezolid; microdialysis; obesity; pharmacokinetics; soft tissue
subject: 615 Pharmazie

description: Background: Linezolid is used for the treatment of soft tissue infections in critically ill patients. However, data for characterizing the pharmacokinetics (PK) and assessing whether effective concentrations are reached at the target site are lacking. We hypothesized that current dosing regimens do not lead to effective concentrations in the plasma and interstitial fluid (ISF) of subcutaneous tissue in obese patients. Methods: As a controlled clinical model, critically ill obese and non-obese patients undergoing intra-abdominal surgery received 600 mg linezolid as a single infusion. Concentrations in the plasma and microdialysate from the ISF of subcutaneous tissue were determined up to 8 h after dosing. Pharmacokinetic analysis was performed by non-compartmental methods. As a therapeutic target, we used fAUC/MIC > 80. Results: Fifteen obese (BMI: 48.7 ± 11.2 kg/m2) and 15 non-obese (23.9 ± 2.1 kg/m2) patients were analyzed. AUC0–8 in ISF decreased by −1.69 mg*h/L (95% CI: −2.59 to −0.79, p < 0.001) for every 10 kg increase in weight. PK in obese patients were characterized by lower maximal plasma concentrations (median 3.8 vs. 8.3 mg/L, p < 0.001) and a higher volume of distribution (41.0 vs. 30.8 L, p < 0.001), and the therapeutic target was not reached for MIC ≥ 1 mg/L in ISF and ≥ 2 mg/L in plasma. Conclusions: Increasing the weight led to a decrease of linezolid concentrations in the plasma and subcutaneous tissue. The current dosing regimen does not seem to produce sufficient concentrations to kill bacteria with MIC ≥ 2 mg/L, especially as empirical antimicrobial therapy in critically ill obese patients.