The distance to M5 from its RR Lyrae variables

A variation of the Baade-Wesselink method has been applied to four RR Lyrae variables in the moderately metal-poor globular cluster M5. The method developed for the analysis utilizes an effective wavelength for each filter and relies on the accuracy of the calibration of absolute flux for bright standard stars by Oke and Gunn (1983), as well as on the accuracy of the absolute emitted fluxes predicted in the near-infrared by the Kurucz (1979) grid of model stellar atmospheres. The results must be viewed as preliminary thus far due to apparent discrepancies between the photometrically and spectroscopically deduced angular diameter-phase relationships which are most apparent in the part of the cycle immediately following maximum light. This restricts the range of phase that can be used to derive the distance to the variables. The best value obtained for the mean of the 4 RR Lyrae stars in M5 is an absorption-corrected intensity mean absolute V magnitude of +1.05 mag (+0.15, -0.25 mag)

From workers education to societal competencies: approaches to a critical, emancipatory education for democracy

This article presents two conceptions concerning critical political education for workers, developed in Germany in the 1960s and the 1990s respectively. First, the conception of “Sociological Imagination and Exemplary Learning” published in 1968 by the German philosopher and sociologist Oskar Negt (1975). Further the elaboration of this conception, which since the 1980s is known as “Societal Competencies“ (Negt, 1986). These competencies concern fundamental knowledge, which enables people to make political judgments, and act politically in democratic societies in an enlightened and reflected way. This conception deliberately distinguishes itself from the economic, instrumentalist notions of key qualifications and key competencies, which at least since the 1970s have been discussed with the aim of maintaining individual employability and competitiveness. ‘Societal competencies’ aim for individual and collective emancipation, the development of the capability to make judgments, and autonomy in the sense of the enlightened political agency and participation in democratization processes. (DIPF/Orig.

Personality predictors of levels of forgiveness two and a half years after the transgression

The aim of the present study was to explore whether the domains and facets of the five-factor model of personality predicted motivational states for avoidance and revenge following a transgression at a second temporal point distant from the original transgression. A sample of 438 university students, who reported experiencing a serious transgression against them, completed measures of avoidance and revenge motivations around the transgression and five-factor personality domains and facets at time 1, and measures of avoidance and revenge motivations two and a half years later. The findings suggest that neuroticism, and specifically anger hostility, predicts revenge and avoidance motivation

Continuous-wave Doppler-cooling of hydrogen atoms with two-photon transitions

We propose and analyze the possibility of performing two-photon continuous-wave Doppler-cooling of hydrogen atoms using the 1S-2S transition. "Quenching" of the 2S level (by coupling with the 2P state) is used to increase the cycling frequency, and to control the equilibrium temperature. Theoretical and numerical studies of the heating effect due to Doppler-free two-photon transitions evidence an increase of the temperature by a factor of two. The equilibrium temperature decreases with the effective (quenching dependent) width of the excited state and can thus be adjusted up to values close to the recoil temperature.Comment: 11 pages, 4 figures in eps forma

Skepticism Motivated: On the Skeptical Import of Motivated Reasoning

Empirical work on motivated reasoning suggests that our judgments are influenced to a surprising extent by our wants, desires and preferences (Kahan 2016; Lord, Ross, and Lepper 1979; Molden and Higgins 2012; Taber and Lodge 2006). How should we evaluate the epistemic status of beliefs formed through motivated reasoning? For example, are such beliefs epistemically justified? Are they candidates for knowledge? In liberal democracies, these questions are increasingly controversial as well as politically timely (Beebe et al. 2018; Lynch forthcoming, 2018; Slothuus and de Vreese 2010). And yet, the epistemological significance of motivated reasoning has been almost entirely ignored by those working in mainstream epistemology. We aim to rectify this oversight. Using politically motivated reasoning as a case study, we show how motivated reasoning gives rise to three distinct kinds of skeptical challenges. We conclude by showing how the skeptical import of motivated reasoning has some important ramifications for how we should think about the demands of intellectual humility

Observation of dissipative chlorophyll-to-carotenoid energy transfer in light-harvesting complex II in membrane nanodiscs

Abstract Plants prevent photodamage under high light by dissipating excess energy as heat. Conformational changes of the photosynthetic antenna complexes activate dissipation by leveraging the sensitivity of the photophysics to the protein structure. The mechanisms of dissipation remain debated, largely due to two challenges. First, because of the ultrafast timescales and large energy gaps involved, measurements lacked the temporal or spectral requirements. Second, experiments have been performed in detergent, which can induce non-native conformations, or in vivo, where contributions from homologous antenna complexes cannot be disentangled. Here, we overcome both challenges by applying ultrabroadband two-dimensional electronic spectroscopy to the principal antenna complex, LHCII, in a near-native membrane. Our data provide evidence that the membrane enhances two dissipative pathways, one of which is a previously uncharacterized chlorophyll-to-carotenoid energy transfer. Our results highlight the sensitivity of the photophysics to local environment, which may control the balance between light harvesting and dissipation in vivo