Orbital polarization and magnetization for independent particles in disordered media

Formulas for the contribution of the conduction electrons to the polarization and magnetization are derived for disordered systems and within a one-particle framework. These results generalize known formulas for Bloch electrons and the presented proofs considerably simplify and strengthen prior justifications. The new formulas show that orbital polarization and magnetization are of geometric nature. This leads to quantization for a periodically driven Piezo effect as well as the derivative of the magnetization w.r.t. the chemical potential. It is also shown how the latter is connected to boundary currents in Chern insulators. The main technical tools in the proofs are an adaption of Nenciu's super-adiabatic theory to C$^*$-dynamical systems and Bellissard's Ito derivatives w.r.t. the magnetic field.Comment: Errors and misprints corrected; introduction expanded; to appear in CM

The Impact of Losses on Income Tax Revenue and Implicit Tax Rates of Different Income Sources: Evidence from Microsimulation Using Tax Statistics for Germany

In order to calculate the burden of a comprehensive and progressive income tax falling on a certain income source, an apportionment scheme for the entire tax burden has to be chosen. This raises the question of how to deal with losses, which is relevant for Germany in view of the heavy losses from renting. Using micro data from tax statistics we analyze the income tax shares of functional income sources for three apportionment schemes. The choice of the apportionment scheme markedly affects the tax shares of income sources and the implicit tax rates, in particular those of capital income.Income and business income taxation, implicit tax rates by income sources

Effect of color superconductivity on the mass and radius of a quark star

We compare quark stars made of color-superconducting quark matter to normal-conducting quark stars. We focus on the most simple color-superconducting system, a two-flavor color superconductor, and employ the Nambu-Jona-Lasinio (NJL) model to compute the gap parameter and the equation of state. By varying the strength of the four-fermion coupling of the NJL model, we study the mass and the radius of the quark star as a function of the value of the gap parameter. If the coupling constant exceeds a critical value, the gap parameter does not vanish even at zero density. For coupling constants below this critical value, mass and radius of a color-superconducting quark star change at most by ca. 20% compared to a star consisting of normal-conducting quark matter. For coupling constants above the critical value mass and radius may change by factors of two or more

Reducing the expense of ear wax

Ear wax is one of the commonest presenting complaints both in Ear Nose and Throat surgery and in General Practice. The commonest treatment by far given for this condition is Arachis oil (Cerumol®). Results from various studies however show that this appears not to be the most effective treatment and that cheaper options exist which may drastically reduce the costs incurred by the Health Department in this respect. We hereby outline the advantages of the use of 0.9% saline drops in the treatment of ear wax.peer-reviewe

The linked employer-employee dataset of the IAB (LIAB)

"The linked employer-employee dataset of the IAB (LIAB) is created by matching the data of the IAB establishment panel and the process-produced data of the Federal Employment Services (in particular the IAB). The distinctive feature of these data is the combination of information about individuals and details concerning the firms in which these people work. This facilitates a number of new methods of analysis and the first empirical examination of theoretical concepts. This applies not only to economic questions but for all areas of empirical social research. Studies have so far been conducted on subjects in labour economics, personnel economics and sociology. Some versions of the LIAB are accessible via the research data centre (Forschungsdatenzentrum - FDZ) of the Federal Employment Services (Bundesagentur für Arbeit - BA) at the IAB." (Author's abstract, IAB-Doku) ((en))IAB-Linked-Employer-Employee-Datensatz, prozessproduzierte Daten, personenbezogene Daten, Arbeitsmarkt- und Berufsforschung, Datengewinnung, Datenorganisation, Datenaufbereitung

Accelerating Minimal Perfect Hash Function Construction Using GPU Parallelization

Eine Minimale Perfekte Hashfunktion (MPHF) bildet eine Menge von N Schlüsseln kollisionsfrei auf die Menge [N ] := {0, .., N − 1} ab. Diese Thesis leistet einen signifikanten Beitrag für den folgenden generischen MPHF Konstruktionsalgorithmus. Im ersten Schritt werden die Schlüssel in Buckets unterschiedlicher erwarteter Größe verteilt. Wir zeigen, dass die Wahl der erwarteten Bucketgröße ein Optimierungsproblem darstellt welches durch die Euler-Lagrange Gleichung gelöst werden kann. Dies resultiert in eine signifikante Verbesserung im Vergleich zum derzeitigen Stand der Forschung. Im zweiten Schritt werden die Buckets primär in nicht aufsteigender Größe geordnet. Wir zeigen, dass der Platzbedarf verbessert wird wenn Buckets gleicher Größe sekundär in aufsteigender Erwartungsgröße angeordnet werden. Die Buckets werden dann im dritten Schritt in dieser Reihenfolge verarbeitet indem eine Hashfunktion gefunden wird welche alle Schlüssel des Buckets kollisionsfrei auf [N ] abbildet. Abschließend wird für jeden Bucket ein Identifikator der Hashfunktion komprimiert gespeichert. Wir präsentieren eine neue Kompressionstechnik, welche die Identifikatoren in unterschiedliche Enkodierer anordnet, sodass alle Identifikatoren innerhalb eines Enkodierers der gleichen statistischen Verteilung folgen. Dies verbessert die Komprimierbarkeit der Identifikatoren. Wir nutzen die parallele Leistungsfähigkeit von GPUs um die Konstruktion von MPHFs weiter zu beschleunigen. Unsere GPU Implementierung konstruiert eine MPHF mit 1,73 Bits pro Schlüssel in nur 36 ns pro Schlüssel mit einer CPU Abfragezeit von 44 ns. Eine solch geringe Abfragezeit bei gleichzeitig niedrigem Platzbedarf ist nach heutigem Stand, wie z.B. mit PTHash, nicht erreichbar. Eine MPHF, die einen höheren Platzbedarf von 1,88 Bits pro Schlüssel aufweist, wird mit unserer Implementierung 9926 mal schneller konstruiert als durch PTHash. Die meisten unserer Beiträge sind über unsere spezifische Implementierung hinaus anwendbar und können selbst modernste Techniken weiter verbessern

Gapless phases of colour-superconducting matter

We discuss gapless colour superconductivity for neutral quark matter in β equilibrium at zero as well as at nonzero temperature. Basic properties of gapless superconductors are reviewed. The current progress and the remaining problems in the understanding of the phase diagram of strange quark matter are discussed

Phase diagram of dense neutral three-flavor quark matter

We study the phase diagram of dense, locally neutral three-flavor quark matter as a function of the strange quark mass, the quark chemical potential, and the temperature, employing a general nine-parameter ansatz for the gap matrix. At zero temperature and small values of the strange quark mass, the ground state of matter corresponds to the color-flavor-locked (CFL) phase. At some critical value of the strange quark mass, this is replaced by the recently proposed gapless CFL (gCFL) phase. We also find several other phases, for instance, a metallic CFL (mCFL) phase, a so-called uSC phase where all colors of up quarks are paired, as well as the standard two-flavor color-superconducting (2SC) phase and the gapless 2SC (g2SC) phase

Candidate amino acids involved in H+ gating of acid-sensing ion channel 1a

Acid-sensing ion channels are ligand-gated cation channels, gated by extracellular H+. H+ is the simplest ligand possible, and whereas for larger ligands that gate ion channels complex binding sites in the three-dimensional structure of the proteins have to be assumed, H+ could in principle gate a channel by titration of a single amino acid. Experimental evidence suggests a more complex situation, however. For example, it has been shown that extracellular Ca2+ ions compete with H+; probably Ca2+ ions bound to the extracellular loop of ASICs stabilize the closed state of the channel and have to be displaced before the channel can open. In such a scheme, amino acids contributing to Ca2+ binding would also be candidates contributing to H+ gating. In this study we systematically screened more than 40 conserved, charged amino acids in the extracellular region of ASIC1a for a possible contribution to H+ gating. We identified four amino acids where substitution strongly affects H+ gating: Glu63, His72/His73, and Asp78. These amino acids are highly conserved among H+-sensitive ASICs and are candidates for the “H+ sensor” of ASICs