Decoding implicit hate speech: The example of antisemitism

This article deals with the problem and the different levels of implicity in the context of antisemitic hate speech. By means of authentic examples stemming from social media debates, we show how alluded antisemitic concepts can be inferred on the basis of conservative interpretation. We point out the role of different sources of knowledge in reconstructing the ideas implied in a statement as well as potential sources of error in the interpretation process. The article thus focuses on the methods and findings of the interdisciplinary research project "Decoding Antisemitism" conducted at the Center for Research on Antisemitism (ZfA) at TU Berlin. By doing so, it explains the procedure of qualitative content analysis as a fruitful approach to understand the actual repertoire of antisemitic hate speech online

Hybrid scalar/vector implementations of Keccak and SPHINCS+ on AArch64

This paper presents two new techniques for the fast implementation of the Keccak permutation on the A-profile of the Arm architecture: First, the elimination of explicit rotations in the Keccak permutation through Barrel shifting, applicable to scalar AArch64 implementations of Keccak-f1600. Second, the construction of hybrid implementations concurrently leveraging both the scalar and the Neon instruction sets of AArch64. The resulting performance improvements are demonstrated in the example of the hash-based signature scheme SPHINCS+, one of the recently announced winners of the NIST post-quantum cryptography project: We achieve up to 1.89× performance improvements compared to the state of the art. Our implementations target the Arm Cortex-{A55,A510,A78,A710,X1,X2} processors common in client devices such as mobile phones

Cumulant approach to weakly doped antiferromagnets

We present a new approach to static and dynamical properties of holes and spins in weakly doped antiferromagnets in two dimensions. The calculations are based on a recently introduced cumulant approach to ground--state properties of correlated electronic systems. The present method allows to evaluate hole and spin--wave dispersion relations by considering hole or spin excitations of the ground state. Usually, these dispersions are found from time--dependent correlation functions. To demonstrate the ability of the approach we first derive the dispersion relation for the lowest single hole excitation at half--filling. However, the main purpose of this paper is to focus on the mutual influence of mobile holes and spin waves in the weakly doped system. It is shown that low-energy spin excitations strongly admix to the ground--state. The coupling of spin waves and holes leads to a strong suppression of the staggered magnetization which can not be explained by a simple rigid--band picture for the hole quasiparticles. Also the experimentally observed doping dependence of the spin--wave excitation energies can be understood within our formalism.Comment: REVTEX, 25 pages, 7 figures (EPS), to be published in Phys. Rev.

Fast and Clean: Auditable high-performance assembly via constraint solving

Handwritten assembly is a widely used tool in the development of high-performance cryptography: By providing full control over instruction selection, instruction scheduling, and register allocation, highest performance can be unlocked. On the flip side, developing handwritten assembly is not only time-consuming, but the artifacts produced also tend to be difficult to review and maintain – threatening their suitability for use in practice. In this work, we present SLOTHY (Super (Lazy) Optimization of Tricky Handwritten assemblY), a framework for the automated superoptimization of assembly with respect to instruction scheduling, register allocation, and loop optimization (software pipelining): With SLOTHY, the developer controls and focuses on algorithm and instruction selection, providing a readable “base” implementation in assembly, while SLOTHY automatically finds optimal and traceable instruction scheduling and register allocation strategies with respect to a model of the target (micro)architecture. We demonstrate the flexibility of SLOTHY by instantiating it with models of the Cortex-M55, Cortex-M85, Cortex-A55 and Cortex-A72 microarchitectures, implementing the Armv8.1-M+Helium and AArch64+Neon architectures. We use the resulting tools to optimize three workloads: First, for Cortex-M55 and Cortex-M85, a radix-4 complex Fast Fourier Transform (FFT) in fixed-point and floating-point arithmetic, fundamental in Digital Signal Processing. Second, on Cortex-M55, Cortex-M85, Cortex-A55 and Cortex-A72, the instances of the Number Theoretic Transform (NTT) underlying CRYSTALS-Kyber and CRYSTALS-Dilithium, two recently announced winners of the NIST Post-Quantum Cryptography standardization project. Third, for Cortex-A55, the scalar multiplication for the elliptic curve key exchange X25519. The SLOTHY-optimized code matches or beats the performance of prior art in all cases, while maintaining compactness and readability

Stickoxide, Partikel und Kohlendioxid: Grenzwerte, Konflikte und Handlungsmöglichkeiten kommunaler Luftreinhaltung im Verkehrsbereich: Informationen und Empfehlungen für Mitarbeiter deutscher Kommunen

Die ab dem 1.1.2010 geltenden erweiterten Luftqualitätsgrenzwerte stellen die Kom-munen vor allem in verkehrlich belasteten Gebieten vor Probleme. Zum einen haben die Kommunen sicherzustellen, dass die Immissionsgrenzwerte eingehalten werden, zum anderen stehen ihnen aber nur eine Reihe beschränkt wirkungsvoller Maßnahmen zur Verfügung. Wie können die (Groß-) Städte darauf reagieren? Zunächst kann festgehalten werden, dass der Verkehrsbereich zukünftig den Schwerpunkt von Maßnahmen zu Klimaschutz und Luftreinhaltung bilden muss. Die wesentlichen urbanen Problemfelder werden durch den Verkehr bestimmt; bei den relevanten Luftschadstoffen stellen Fahrzeuge mit Dieselmotoren die Hauptemittenten dar und zur Reduktion der CO2-Emissionen müssen alle Fahrzeuge deutlich mehr beitragen als bisher. In der Vergangenheit war die Reduktion von Verkehrsemissionen vorrangig als Frage der Weiterentwicklung der Fahrzeugtechnik interpretiert worden. Da die technischen Weiterentwicklungen allein für die Problemlösung nicht ausreichen, sind grundsätzliche Änderungen von Verkehrsverhalten und Verkehrssystemen unumgänglich. Eine Verbesserung der Raumordnung, weniger Zersiedelung, eine multifunktionale Stadt der kurzen Wege und ein anderes Mobilitätsverhalten der Bevölkerung weisen die höchsten Reduktionspotentiale auf, wirken aber vor allem langfristig. Eine Übersicht mit denkbaren Maßnahmengruppen zur Erreichung der Luftqualitäts- und Klimaschutzziele wurde erarbeitet, die zur Entwicklung spezifischer Pakete von Kommunen genutzt werden kann

Immundefekte bei chronischer Rhinosinusitis : eine bedeutende und oft unterschätzte Ursache

Background Chronic rhinosinusitis (CRS) is one of the most frequent chronic diseases. Among these patients the prevalence of immune defects is higher than in the healthy general population. Methods A selective review of the literature was carried out in PubMed and Medline covering the period between 2008 and 2019. Additionally, recent German publications in journals not listed in the abovementioned databases were analyzed. Results The diagnostic workflow with respect to the immunodeficiency consists of a detailed anamnesis and physical examination, laboratory tests and the antibody reaction to polysaccharide vaccines and antigens. Beside antibiotic treatment, vaccinations and immunoglobulin replacement are available. Notwithstanding the above, functional endoscopic surgery of the paranasal sinuses should be performed according to guideline recommendations. Conclusion Patients with CRS who do not sufficiently respond to conservative and surgical treatment should be checked for underlying immunodeficiencies

Spin polarons in triangular antiferromagnets

The motion of a single hole in a 2D triangular antiferromagnet is investigated using the t-J model. The one-hole states are described by strings of spin deviations around the hole. Using projection technique the one-hole spectral function is calculated. For large J/t we find low-lying quasiparticle-like bands which are well separated from an incoherent background by a gap of order J. However, for small J/t this gap vanishes and the spectrum becomes broad over an energy range of several t. The results are compared with SCBA calculations and numerical data.Comment: 4 pages, 6 figs, to be publish in PR

Hole motion in an arbitrary spin background: Beyond the minimal spin-polaron approximation

The motion of a single hole in an arbitrary magnetic background is investigated for the 2D t-J model. The wavefunction of the hole is described within a generalized string picture which leads to a modified concept of spin polarons. We calculate the one-hole spectral function using a large string basis for the limits of a Neel ordered and a completely disordered background. In addition we use a simple approximation to interpolate between these cases. For the antiferromagnetic background we reproduce the well-known quasiparticle band. In the disordered case the shape of the spectral function is found to be strongly momentum-dependent, the quasiparticle weight vanishes for all hole momenta. Finally, we discuss the relevance of results for the lowest energy eigenvalue and its dispersion obtained from calculations using a polaron of minimal size as found in the literature.Comment: 13 pages, 8 figures, to appear in Phys. Rev.

Soziale Erwünschtheit und Skalenformat als Einflussfaktoren bei der Beantwortung von Wahrscheinlichkeitsaussagen

Questionnaire research suggests that all information communicated by the questionnaire is potentially relevant for the respondent and therefore used to build an answer. Research demonstrated that the numeric format of a rating scale influences the answers to attitude questions. This study investigates the potential influence of the numeric format on the answer to probability estimates in the context of social desirability. In a first study events are classified on basis of their social desirability. For the main investigation in each case four socially desired, undesired, and neutral events were presented. Respondents were asked to rate the probability of doing this action by means of three different rating scales (bipolar, negative, neutral). A strong influence of social desirability could be confirmed but no influence of the rating scale format. Implications are discussed.Befunde zum Fragebogendesign legen nahe, dass potentiell jede mit einem Fragebogen kommunizierte Information für Probanden relevant und somit für die Beantwortung bedeutsam ist. So konnte gezeigt werden, dass bei Beantwortung von Einstellungsfragen die numerische Beschriftung der einzelnen Skalenpunkte als Interpretationshilfe herangezogen wird. Die vorliegende Arbeit überprüft, ob diese numerischen Formate einer Ratingskala ebenfalls einen Einfluss auf die Beantwortung von Wahrscheinlichkeitsaussagen haben; auch Interaktionseffekte zwischen Ratingskalenformat und sozialer Erwünschtheit werden untersucht: In einer Vorstudie wurden mehrere Ereignisse hinsichtlich ihrer sozialen und individuellen Erwünschtheit eingeschätzt. In der Hauptuntersuchung wurden jeweils vier sehr erwünschte, sehr unerwünschte oder neutrale Ereignisse in einem 3x3-faktoriellen between-subjects Versuchsdesign jeweils mittels dreier verschiedener Ratingskalenformate (bipolar, negativ, neutral) hinsichtlich ihrer individuellen Ausführungswahrscheinlichkeit eingeschätzt. Es zeigt sich ein starker Einfluss der sozialen Erwünschtheit auf das Antwortverhalten während Skalenformate in Abweichung von den Hypothesen auch in Interaktion mit sozialer Erwünschtheit keine Auswirkungen zeigen. Empfehlungen zur Gestaltung von Fragebögen werden abgeleitet

Efficient Multiplication of Somewhat Small Integers using Number-Theoretic Transforms

Conventional wisdom purports that FFT-based integer multiplication methods (such as the Schönhage-Strassen algorithm) begin to compete with Karatsuba and Toom-Cook only for integers of several tens of thousands of bits. In this work, we challenge this belief, leveraging recent advances in the implementation of number-theoretic transforms (NTT) stimulated by their use in post-quantum cryptography. We report on implementations of NTT-based integer arithmetic on two Arm Cortex-M CPUs on opposite ends of the performance spectrum: Cortex-M3 and Cortex-M55. Our results indicate that NTT-based multiplication is capable of outperforming the big-number arithmetic implementations of popular embedded cryptography libraries for integers as small as 2048 bits. To provide a realistic case study, we benchmark implementations of the RSA encryption and decryption operations. Our cycle counts on Cortex-M55 are about 10× lower than on Cortex-M3