A self-consistent approach to the Wigner-Seitz treatment of soliton matter

We propose a self-consistant approach to the treatment of nuclear matter as a crystal of solitons in the Wigner-Seitz approximation. Specifically, we use a Bloch-like boundary condition on the quarks at the edge of a spherical cell which allows the dispersion relation for a given radius to be calculated self-consistently along with the meson fields; in previous work some ansatz for the dispersion relation has always been an input. Results in all models are very sensitive to the form of the dispersion relation, so our approach represents a significant advance. We apply the method to both the Friedberg Lee model and the chiral quark-meson model of Birse and Banerjee. Only the latter shows short range repulsion; in the former the transition to a quark plasma occurs at unrealistically low densities.Comment: Revtex; 14 pages with 9 eps figure

Die Flexi-Rente als Instrument zur Erhöhung der Erwerbsbeteiligung

Um einen flexibleren Übergang in den Ruhestand und eine Verlängerung der Lebensarbeitszeit zu erreichen, wurde eine Arbeitsgruppe zur sogenannten Flexi-Rente einberufen. Bisherige Regelungen zum Rentenübergang haben beide Ziele bisher nicht ausreichend erreicht, daher wird für eine starkere Flexibilisierung des Renteneintritts in mehrfacher Hinsicht Reformbedarf gesehen. Zusätzlich zu den Reformen bereits bestehender Regelungen soll der rentenmindernden Wirkung von Abschlägen entgegen gewirkt werden. Die Koalitionsarbeitsgruppe "Flexible Übergänge vom Erwerbsleben in den Ruhestand" hat daher einen Vorschlag entworfen, der mehrere Änderungen beinhaltet: Die neue stufenlose Form der Teilrente vermeidet Fehlanreize. Die Regelung wird flexibler, vermeidet Unsicherheiten und wird dadurch besser planbar. Höhere, aber dennoch fixe Hinzuverdienstgrenzen setzen einen zusätzlichen Beschäftigungsanreiz. Dieser wirkt stärker fur Bezieher niedrigerer Einkommen. Die Neuregelung der Teilrente ist insofern als Fortschritt zu sehen, als Fehlanreizen, die eine Beschäftigung im Alter unattraktiv machen, entgegengewirkt wird. Die Gesamtwirkung ist dadurch begrenzt, dass die Zugangsvoraussetzungen zum vorzeitigen Rentenbezug relativ hoch sind. Die Erhöhung der Hinzuverdienstgrenzen auf monatlich 850 Euro kann ebenso wie die Vermeidung der Grundsicherung im Alter und das Ansparen gegen die Inkaufnahme von Abschlägen potenzielle Altersarmut begrenzen. Die Anpassung an das Äquivalenzprinzip in der Arbeitslosenversicherung durch den Wegfall der Arbeitgeberbeiträge fur Beschäftigte ab dem Eintrittsalter in die Regelrente ist gegenüber den Anreizen abzuwägen, diese gegenüber jüngeren Erwerbstätigen zu bevorzugen. Dass sich Beiträge zur Rentenversicherung auch für arbeitende Rentner rentensteigernd auswirken, ist gut und richtig.Current regulations concerning flexible entry into retirement are considered insufficient. In order to achieve more flexible transitions into retirement and to extend working life, a working group on the so-called Flexi-Pension was set up. Its proposal also includes a revision in order to prevent reduction effects of discounts on pension income for insured persons potentially affected by social assistance. The renewal of the so-called partial pension avoids the disincentives of the current regulation: The former regulation with rigid limits on additional income is replaced by a continuous adjustment. This is more flexible, reduces uncertainty, and makes overall income better predictable for the insured. A higher, but fixed, ceiling of additional income is a more effective incentive for low-paid workers. The new regulations on the partial pension can be seen as progress since some disincentives have been removed. After the reforms, employment at a higher age will become more attractive. However, the overall effect is limited by the fact that the requirements for partial pension entrance are relatively high. For retirees, new regulations include an increase in the supplementary income. Currently, parallel income to a state pension is limited to 450 euros per month. Later the ceiling for extra income will be 850 euros per month. This regulation is intended to support labour market participation and avoid poverty in old age. New regulations for insured persons who are affected by discounts and social assistance as well as an extended period for saving to prevent the discounts for early retirement will also help to avoid poverty in old age. Employer's contributions to unemployment insurance for workers older than 65 years will be removed in the future. Though this the work of older employees will become cheaper than the work of persons under 65. However, this incentive to employ persons of higher ages must be balanced against the employment opportunities of younger workers. Currently, contributions of retirees to the pension scheme do not raise pension income. The suggestion that these contributions also be accounted for is to the benefit of both the employer and those insured

Contrast agents for molecular photoacoustic imaging.

Photoacoustic imaging (PAI) is an emerging tool that bridges the traditional depth limits of ballistic optical imaging and the resolution limits of diffuse optical imaging. Using the acoustic waves generated in response to the absorption of pulsed laser light, it provides noninvasive images of absorbed optical energy density at depths of several centimeters with a resolution of ∼100 μm. This versatile and scalable imaging modality has now shown potential for molecular imaging, which enables visualization of biological processes with systemically introduced contrast agents. Understanding the relative merits of the vast range of contrast agents available, from small-molecule dyes to gold and carbon nanostructures to liposome encapsulations, is a considerable challenge. Here we critically review the physical, chemical and biochemical characteristics of the existing photoacoustic contrast agents, highlighting key applications and present challenges for molecular PAI.This work was supported by CRUK (Career Establishment Award no. C47594/A16267 to J.W. and S.E.B., Core Funding C14303/A17197 to J.W. and S.E.B.), the European Commission (CIG FP7-PEOPLE- 2013-CIG-630729 to J.W. and S.E.B.), the EPSRC-CRUK Cancer Imaging Centre in Cambridge and Manchester (C197/A16465 to J.W. and S.E.B.), King’s College London and University College London Comprehensive Cancer Imaging Centre Cancer Research UK & Engineering and Physical Sciences Research Council, in association with the Medical Research Council and the Department of Health, UK (P.B.), and the European Union (project FAMOS FP7 ICT, contract 317744 to P.B.).This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nmeth.392

Rente mit 63 und betriebliche Reaktionen

Anlässlich des ersten Jahrestages der Einführung der Rente mit 63 liefert dieser Bericht Befunde aus der IAB-Stellenerhebung zur betrieblichen Betroffenheit und zu den Anpassungsstrategien der Betriebe. Die betrieblichen Reaktionen auf die Option einer früheren Verrentung sind vor allem vor dem Hintergrund der Diskussion um die Fachkräftesicherung von Interesse. 11,4 Prozent der Betriebe haben angegeben, dass mindestens ein Mitarbeiter aufgrund der Einführung der Rente mit 63 ausgeschieden ist oder dass sie dies erwarten. Aus demografischen Gründen trifft dies stärker auf den Osten und auf bestimmte Wirtschaftszweige zu, die einen höheren Anteil Älterer aufweisen. Erwartungsgemäß steigt die Betroffenheit mit der Betriebsgröße. Die Reaktionen auf das Ausscheiden von Mitarbeitern sind von betrieblichen Flexibilitätspotenzialen abhängig: So sind kleine Betriebe in ihren Möglichkeiten zur internen Umstrukturierung oder ihren Chancen, Personal extern zu rekrutieren, stärker limitiert als größere Betriebe. Zum Teil versuchen Betriebe, ältere Mitarbeiter über attraktive Angebote wie höhere Löhne, Prämien und Beförderungen im Betrieb zu halten. Inwieweit dies geschieht, ist auch vom Wirtschaftszweig abhängig. Betriebe wollen Ältere häufiger dann halten, wenn sie eine vergleichsweise hö-herqualifizierte Belegschaft haben oder wenn sie in Branchen tätig sind, in denen es Anzeichen für Rekrutierungsschwierigkeiten gibt

Magnetic properties of restacked 2D spin 12\frac{1}{2} honeycomb RuCl3_3 nanosheets

Spin $\frac{1}{2}$ honeycomb materials have gained substantial interest due to their exotic magnetism and possible application in quantum computing. However, in all current materials out-of-plane interactions are interfering with the in-plane order, hence a true 2D magnetic honeycomb system is still of demand. Here, we report the exfoliation of the magnetic semiconductor $\alpha$-RuCl$_3$ into the first halide monolayers and the magnetic characterization of the spin $\frac{1}{2}$ honeycomb arrangement of turbostratically stacked RuCl$_3$ monolayers. The exfoliation is based on a reductive lithiation/hydration approach, which gives rise to a loss of cooperative magnetism due to the disruption of the spin $\frac{1}{2}$ state by electron injection into the layers. After an oxidative treatment, cooperative magnetism similar to the bulk is restored. The oxidized pellets of restacked single layers feature a magnetic transition at T$_N$ = 7 K in the in-plane direction, while the magnetic properties in the out-of-plane direction vastly differ from bulk $\alpha$-RuCl$_3$. The macroscopic pellets of RuCl$_3$ therefore behave like a stack of monolayers without any symmetry relation in the stacking direction. The deliberate introduction of turbostratic disorder to manipulate the spin structure of RuCl$_3$ is of interest for research in frustrated magnetism and complex magnetic order as predicted by the Kitaev-Heisenberg model.Comment: 18 pages, 5 figures, supporting information added with 11 pages and 11 figure

SAsSy – Scrutable Autonomous Systems

Abstract. An autonomous system consists of physical or virtual systems that can perform tasks without continuous human guidance. Autonomous systems are becoming increasingly ubiquitous, ranging from unmanned vehicles, to robotic surgery devices, to virtual agents which collate and process information on the internet. Existing autonomous systems are opaque, limiting their usefulness in many situations. In order to realise their promise, techniques for making such autonomous systems scrutable are therefore required. We believe that the creation of such scrutable autonomous systems rests on four foundations, namely an appropriate planning representation; the use of a human understandable reasoning mechanism, such as argumentation theory; appropriate natural language generation tools to translate logical statements into natural ones; and information presentation techniques to enable the user to cope with the deluge of information that autonomous systems can provide. Each of these foundations has its own unique challenges, as does the integration of all of these into a single system.

Radiation-induced second malignancies after involved-node radiotherapy with deep-inspiration breath-hold technique for early stage Hodgkin Lymphoma: a dosimetric study

BACKGROUND: To estimate the risk of radiation induced second cancers after radiotherapy using deep-inspiration breath-hold (DI) technique with three-dimensional conformal (3DCRT) and volumetric arc therapy (VMAT) for patients with Hodgkin’s lymphoma (HL). METHODS: Early-stage HL with mediastinal and supraclavicular involvement was studied using an Alderson phantom. A whole body CT was performed and all tissues were delineated. The clinical target volumes and planning target volumes (PTV) were determined according to the German Hodgkin study group guidelines. Free-breathing (FB) technique and DI technique were simulated by different safety margins for the PTV definition. In both cases, 30 Gy in 15 fractions was prescribed. Second cancer risk was estimated for various tissues with a second cancer model including fractionation. RESULTS: When compared with FB-3DCRT, estimated relative life time attributable risk (LAR) of cancer induction after DI-3DCRT was 0.86, 0.76, 0.94 and 0.92 for breast, lung, esophagus and stomach, respectively. With DI-VMAT, the corresponding values were 2.05, 1.29, 1.01, 0.93, respectively. For breast cancer, the LAR observed with DI-VMAT was not substantially distinguishable from the LAR computed for mantle RT with an administered dose of 40 Gy. CONCLUSIONS: This study suggests that DI may reduce the LAR of secondary cancers of all OARs and may be a valuable technique when using 3DCRT. Conversely, VMAT may increase substantially the LAR and should be cautiously implemented in clinical practice

Development of Novel Molecular Imaging Contrast Agents for Detection of Oxidative Stress

An early and precise diagnosis of disease is a crucial requirement for fast and targeted therapy in the era of precision medicine. Most diseases possess molecular alterations in their early stages, which precede noticeable morphological changes. One important molecular change that contributes to dysfunction in a wide range of pathologies, including cancer and neurological disorders, is an increase in levels of reactive oxygen species (ROS) and associated oxidative damage. Our understanding of how ROS influence disease biology is currently limited by our inability to perform sensitive and specific assessment of ROS levels with high spatial and temporal resolution in living systems. The goal of the research described in this thesis was to overcome the challenge of assessing ROS during disease development in cancer and neurodegenerative disease through the design, synthesis and validation of two classes of novel bifunctional, ROS-sensitive contrast agents. To shed light on the complex redox biology in cancer, the new method of photoacoustic imaging was exploited. A novel activatable, targeted near infrared cyanine dye is reported that enables specific detection of pathological levels of hydrogen peroxide, a major and abundant ROS in living organisms. This approach uses photoacoustic and fluorescence imaging in cancerous tissue to evaluate the performance of the new probe under in vitro and in vivo conditions. In neurodegeneration, there exists a bidirectional interaction between oxidative stress and protein aggregates. To scrutinise this relationship, both bulk and single-molecule fluorescence imaging methods were used to assess the capability of novel bifunctional fluorescence dyes to localise the presence of the two putative disease-causing species, ROS and protein aggregates, simultaneously under in vitro conditions. The data shown here provides a promising foundation for the systematic design of contrast agents based on small molecule dyes, that possess ideal optical and biological characteristics to study oxidative stress in a broad range of pathological applications with high temporal and spatial resolution.Cancer Research U

Revision der IAB-Stellenerhebung: Hintergründe, Methode und Ergebnisse

Die Stellenerhebung des Instituts für Arbeitsmarkt- und Berufsforschung (IAB) liefert quartalsweise repräsentative Daten über Anzahl und Struktur der offenen Stellen, die aus anderen Quellen nicht verfügbar und deshalb einmalig sind. Einbezogen sind gemeldete und nicht gemeldete offene Stellen. Umfangreiche Überprüfungen und Tests führten zur Entwicklung eines neuen Hochrechnungsverfahrens. Im Ergebnis kommt es zu einer Abwärtsrevision beim gesamtwirtschaftlichen Stellenangebot. Der hier vorgelegte Forschungsbericht gibt zunächst einen Überblick über Ziele und Inhalte der IAB-Stellenerhebung und beschreibt anschließend die einzelnen Schritte bei der Entwicklung eines neuen Hochrechnungsverfahrens, ausgehend vom bisher angewendeten Verfahren. Er präsentiert die neue Hochrechnungsmethode und zeigt, dass sich durch ihre Anwendung die Qualität der Befragungsergebnisse verbessert. Mit der neuen Hochrechnung werden für das gesamtwirtschaftliche Stellenangebot revidierte Zeitreihen bis zum Jahr 2000 zurück vorgelegt, wobei die Vergleichbarkeit zwischen dem Zeitraum vor 2010 und ab 2010 eingeschränkt ist. Der Forschungsbericht präsentiert die Ergebnisse für beide Zeiträume und jeweils für den Vergleich von neuer und alter Hochrechnung.The German Job Vacancy Survey delivers representative data on the number and structure of vacancies in Germany. Such data cannot be derived from other sources and are therefore unique. The survey includes registered and non-registered vacancies. In course of extensive tests and reviews a new extrapolation procedure has been developed. As a result, the aggregate vacancy supply is revised downwards. The research report is organised as follows: Firstly, an overview about the aim and content of the German Job Vacancy Survey is given. Subsequently, the evolution of the new extrapolation procedure is described. Thirdly, the new method is presented and it is shown that the adaption of it significantly improves the quality of the survey results. Along with the new extrapolation procedure a revised time series dating back to 2000 is given. However, figures before and after 2010 cannot be directly compared. The research report presents the results for both time periods and compares the new and old extrapolation methods