Restoration of chiral symmetry in light-front finite temperature field theory

We investigate the properties of $qq$ and $q\bar q$ states in hot and dense quark matter in the framework of light-front finite temperature field theory. Presently we use the Nambu Jona-Lasinio model of QCD and derive the gap equation at finite temperature and density. We study pionic and scalar diquark dynamics in quark matter and calculate the masses and the Mott dissociation as a function of the temperature $T$ and the chemical potential $\mu$. For the scalar diquark we determine the critical temperature of color superconductivity.Comment: 4 pages, 3 figures, Presented by S.Strau\ss at Light-Cone 2004, Amsterdam, 16 - 20 Augus

Understanding financial institutions – The role of reading economic news in Germany and the UK

This chapter argues that the news media play an important factor in educating the public about financial institutions. It presents some novel survey results, exploring the role of economic news use for the perceived understanding of financial institutions in Germany and the UK. Two web-based surveys were conducted: one in the UK in winter 2018 and one in Germany in summer 2019. Findings show that economic news use is positively related with a better perceived understanding of financial institutions in both countries, even after controlling for demographics and financial socialization. We find that the level of perceived understanding of financial institutions is positively related with education and income and negatively related with being female. The need for information significantly impacted the relationship between economic news use and understanding of financial institutions in the UK but not in Germany. Practical implications for economic and financial news journalists are discussed

Image analysis as PAT-Tool for use in extrusion-based bioprinting

The technology of bioprinting is arousing a growing interest in biopharmaceutical research and industry. In order to accelerate process development in the field of bioprinting, image-based analysis methods are non-invasive, time- and cost-saving tools which are useable for printer characterization, bioink printability evaluation, and process optimization. Image processing can also be used for the study of reproducibility, since reliable production is important in the transition from research to industrial application, and more precisely to clinical studies. This study revolves around the establishment of an automated and image-based line analysis method for bioprinting applications which enables an easy comparison of 3D-printed lines. Diverse rheological properties of bioinks and the printing process affect the geometry of the resulting object. The line represents a simple geometry, where the influence of the rheological properties and printing parameters is directly apparent. Therefore, a method for line analysis was developed on the basis of image recognition. At first, the method is tested for several substances such as Nivea®, pure and colored Kolliphor solutions, and two commercially available hydrogel formulations which can be used as bioinks. These are Biogelx™-ink-RGD by Biogelx and Cellink® Bioink by Cellink. The examination of limitations showed that transparent materials such as Kolliphor-based solutions cannot be analyzed with the developed method whereas opaque materials such as Nivea® and both bioinks can be analyzed. In the course of process characterization, the method was used to investigate the shrinkage behavior for both bionks. With the help of the line analysis tool, a shrinkage behavior of both bioinks was demonstrated and thus, process time could be identified as a critical process parameter

Digital diplomacy in GCC countries: strategic communication of Western embassies on Twitter

Drawing upon online communication research, this study identifies six effective communication strategies for social media-based diplomacy on Twitter: interactive, personalized, positive, relevant, and transparent communication among a broad network of stakeholders. By using an extensive mix-method design (i.e., combining a manual content and automated network analyses, N = 4438 tweets), this research examines to what extent these communication strategies are adopted on Twitter by Western embassies active in countries from the Gulf Cooperation Council. We found that embassies are not utilizing social media to its full potential. Although embassies are transparent, use positive sentiment in their online communication and post relevant information to their stakeholders, they hardly engage in direct interactive and personal communication, and only reach out to a limited group of stakeholders. We recommend embassies to put more emphasis on two-way interactive communication with a vast variety of stakeholders

Solar and Atmospheric Neutrinos: Background Sources for the Direct Dark Matter Searches

In experiments for direct dark matter searches, neutrinos coherently scattering off nuclei can produce similar events as Weakly Interacting Massive Particles (WIMPs). The calculated count rate for solar neutrinos in such experiments is a few events per ton-year. This count rate strongly depends on the nuclear recoil energy threshold achieved in the experiments for the WIMP search. We show that solar neutrinos can be a serious background source for direct dark matter search experiments using Ge, Ar, Xe and CaWO_4 as target materials. To reach sensitivities better than approximatly 10^-10 pb for the elastic WIMP nucleon spin-independent cross section in the zero-background limit, energy thresholds for nuclear recoils should be approximatly >2.05 keV for CaWO_4, >4.91 keV for Ge, >2.89 keV for Xe, and >8.62 keV for Ar as target material. Next-generation experiments should not only strive for a reduction of the present energy thresholds but mainly focus on an increase of the target mass. Atmospheric neutrinos limit the achievable sensitivity for the background-free direct dark matter search to approximatly >10^-12 pb.Comment: accepted by Astroparticle Physic

Fission studies with 140 MeV α\bm{\alpha}-Particles

Binary fission induced by 140 MeV $\alpha$-particles has been measured for $^{\rm nat}$Ag, $^{139}$La, $^{165}$Ho and $^{197}$Au targets. The measured quantities are the total kinetic energies, fragment masses, and fission cross sections. The results are compared with other data and systematics. A minimum of the fission probability in the vicinity $Z^2/A=24$ is observed.Comment: 4 figures, 2 table

Modulating between 2e^- and 4e^- pathway in the oxygen reduction reaction with laser-synthesized iron oxide-grafted nitrogen-doped carbon

In this study, we demonstrate the tuning of the oxygen reduction reaction (ORR) by iron/iron oxide nanoparticle grafted laser-patterned nitrogen-doped carbon (LP-NC) electrodes. Depending on the preparation route, i.e. addition of a molecular Fe(NO3)2 precursor before (route 1) or after pre-carbonization (route 2) of the citric acid / urea precursors, either the 4e- or the 2e- pathway in the ORR is facilitated leading to either H2O or H2O2 as a reaction product, respectively. The kinetic reaction conditions afford mixed valence metal oxide nanoparticles embedded in LP-NC in the form of either Fe2O3/Fe or Fe2O3/FeO/Fe, respectively, facilitated by an in situ carbothermal reduction during the laser-induced carbonization. In HR(S)TEM analysis we found evidence for the occurrence of Fe2O3 in the η- or α- phase, depending on the preparation route. Reciprocally, the graphitization is also affected by the preparation route leading to either homogeneous graphitization or locally a graphitized shell structures around the nanoparticles. In the 4e- mediated ORR facilitated by η-Fe2O3/Fe@LP-NC onset potentials as low as 0.70 V (vs. RHE) with a H2O2 production efficiency 4% and 10 % in alkaline and neutral electrolyte, respectively, were determined. On the other hand, α-Fe2O3/FeO/Fe@LP-NC present onset potentials for the 2e- mediated ORR is as low as 0.77 with a H2O2 production efficiency of nearly 80%