Max Planck Society

About: Max Planck Society is a nonprofit organization based out in Munich, Germany. It is known for research contribution in the topics: Galaxy & Population. The organization has 148289 authors who have published 406224 publications receiving 19522268 citations. The organization is also known as: Max-Planck-Gesellschaft zur Förderung der Wissenschaften e. V. & MPG.

Store depletion and calcium influx

Abstract: Calcium influx in nonexcitable cells regulates such diverse processes as exocytosis, contraction, enzyme control, gene regulation, cell proliferation, and apoptosis. The dominant Ca2+ entry pathway in these cells is the store-operated one, in which Ca2+ entry is governed by the Ca2+ content of the agonist-sensitive intracellular Ca2+ stores. Only recently has a Ca2+ current been described that is activated by store depletion. The properties of this new current, called Ca2+ release-activated Ca2+ current (ICRAC), have been investigated in detail using the patch-clamp technique. Despite intense research, the nature of the signal that couples Ca2+ store content to the Ca2+ channels in the plasma membrane has remained elusive. Although ICRAC appears to be the most effective and widespread influx pathway, other store-operated currents have also been observed. Although the Ca2+ release-activated Ca2+ channel has not yet been cloned, evidence continues to accumulate that the Drosophila trp gene might encode a store-operated Ca2+ channel. In this review, we describe the historical development of the field of Ca2+ signaling and the discovery of store-operated Ca2+ currents. We focus on the electrophysiological properties of the prototype store-operated current ICRAC, discuss the regulatory mechanisms that control it, and finally consider recent advances toward the identification of molecular mechanisms involved in this ubiquitous and important Ca2+ entry pathway.

The epidemiology of co-occurring addictive and mental disorders: implications for prevention and service utilization.

Abstract: General population data from the National Comorbidity Survey are presented on co-occurring DSM-III-R addictive and mental disorders. Co-occurrence is highly prevalent in the general population and usually due to the association of a primary mental disorder with a secondary addictive disorder. It is associated with a significantly increased probability of treatment, although the finding that fewer than half of cases with 12-month co-occurrence received any treatment in the year prior to interview suggests the need for greater outreach efforts.

Plant responses to insect herbivory: The emerging molecular analysis

Abstract: ▪ Abstract Plants respond to herbivore attack with a bewildering array of responses, broadly categorized as direct and indirect defenses, and tolerance. Plant-herbivore interactions are played out on spatial scales that include the cellular responses, well-studied in plant-pathogen interactions, as well as responses that function at whole-plant and community levels. The plant's wound response plays a central role but is frequently altered by insect-specific elicitors, giving plants the potential to optimize their defenses. In this review, we emphasize studies that advance the molecular understanding of elicited direct and indirect defenses and include verifications with insect bioassays. Large-scale transcriptional changes accompany insect-induced resistance, which is organized into specific temporal and spatial patterns and points to the existence of herbivore-specific trans-activating elements orchestrating the responses. Such organizational elements could help elucidate the molecular control over the d...

Exports and Productivity: A Survey of the Evidence from Firm Level Data

Abstract: While the role of exports in promoting growth in general, and productivity in particular, has been investigated empirically using aggregate data for countries and industries for a long time, only recently have comprehensive longitudinal data at the firm level been used to look at the extent and causes of productivity differentials between exporters and their counterparts which sell on the domestic market only. This paper surveys the empirical strategies applied, and the results produced, in 45 microeconometric studies with data from 33 countries that were published between 1995 and 2004. Details aside, exporters are found to be more productive than non-exporters, and the more productive firms self-select into export markets, while exporting does not necessarily improve productivity.

Tests of general relativity with GW150914

Abstract: The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant’s mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 1013 km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.