How Important Are Wages to the Elderly? Evidence from the New Beneficiary Data System and the Social Security Earnings Test

More than 40 percent of Social Security beneficiaries continue to work after age 65. This research investigates the extent to which these individuals substitute labor across periods in response to anticipated wage changes induced by the Social Security earnings test. While we find that a disproportionate number of individuals choose earnings within a few percentage points of the earnings limit, we find no evidence that these individuals substitute labor supply between

Recent status of the understanding of neutrino-nucleus cross section

In this work we have presented current understanding of neutrino-nucleon/nucleus cross sections in the few GeV energy region relevant for a precise determination of neutrino oscillation parameters and CP violation in the leptonic sector. In this energy region various processes like quasielastic and inelastic production of single and multipion production, coherent pion production, kaon, eta, hyperon production, associated particle production as well as deep inelastic scattering processes contribute to the neutrino event rates.Comment: 9-Pages, 4-figures, Talk given at DAE-HEP Symposium held at Delhi University, 12-16 December, 201

Composite vertices that lead to soft form factors

The momentum-space cut-off parameter $\Lambda$ of hadronic vertex functions is studied in this paper. We use a composite model where we can measure the contributions of intermediate particle propagations to $\Lambda$. We show that in many cases a composite vertex function has a much smaller cut-off than its constituent vertices, particularly when light constituents such as pions are present in the intermediate state. This suggests that composite meson-baryon-baryon vertex functions are rather soft, i.e., they have \Lambda considerably less than 1 GeV. We discuss the origin of this softening of form factors as well as the implications of our findings on the modeling of nuclear reactions.Comment: REVTex, 19 pages, 5 figs(to be provided on request

Vergleichende Untersuchungen zu GPCR-induzierten dynamischen Konformationsänderung in β-arrestin1 und 2

G protein-coupled receptors (GPCRs) constitute the largest family of membrane receptors in human physiology, comprising more than 800 different genes. They sense diverse extracellular signals and initiate intracellular signaling responses via the activation of specific G proteins. The downregulation of GPCR signaling is mediated by four ubiquitously expressed GPCR kinases (GRK2, 3, 5, and 6) and two β-arrestin isoforms (β-arrestin1 and 2). GRKs phosphorylate intracellular domains of active receptors to facilitate high-affinity β-arrestin-binding. Depending on the specific GPCR–β-arrestin interaction, β-arrestins undergo different conformational changes to mediate receptor desensitization, internalization, and mitogen-activated protein kinase (MAPK) signal-amplification. However, the impact of individual GRK isoforms on these processes has not been comprehensively assessed until now. Moreover, whether β-arrestin1 and 2 undergo different conformational changes upon binding to the same GPCR is still unknown. The first part of this thesis focusses on the elaboration of GRK isoform-specific aspects of GPCR signaling. For this, a panel of elven in-house created combinatorial HEK293 knockout cell clones, lacking GRK2/3/5/6 (including four single, two double, four triple, and a quadruple GRK knockout cell line), was extensively used. To investigate GRK isoform-specific β-arrestin recruitment, a NanoLuc–HaloTag-based BRET system was established and combined with the unique possibility to vary individual GRK expression levels using different ΔGRK knockout cell lines. Hence, the GRK-specificity of β-arrestin-binding was assessed with two different strategies: first, utilizing the triple GRK knockout cell lines, featuring the endogenous expression of only one GRK isoform (ΔGRK3/5/6, ΔGRK2/5/6, ΔGRK2/3/6, ΔGRK2/3/5), and additionally by re-introduction of a single GRK isoform in the quadruple GRK knockout cell line (ΔQ-GRK)