Search results

It has long been argued that geographic co-location supports knowledge spillovers. More recently, this argument has been challenged by showing that knowledge spillovers mainly flow through social networks, which may or may not be localized at various geographic scales. We further scrutinize the conjecture of geographically bounded knowledge spillovers by focusing on knowledge flows between academi

Acceptance, attrition and outcome of the same outpatient treatment programme for alcoholics was studied first in a non-randomized and later in a randomized study. There was a lower (15%) rate of acceptance and a higher (19%) rate of attrition in the randomized study. Among treatment completers drinking outcome during the third year after commencement of treatment did not differ between the non-ran

Context. Gaia Data Release 1 (DR1) contains astrometric results for more than 1 billion stars brighter than magnitude 20.7 based on observations collected by the Gaia satellite during the first 14 months of its operational phase. Aims. We give a brief overview of the astrometric content of the data release and of the model assumptions, data processing, and validation of the results. Methods. For s

Purpose: Inflammation with leukocytic infiltration, degradation of extracellular matrix (ECM), and depletion of vascular smooth muscle cells (VSMC) are pathological hallmarks of abdominal aortic aneurysm (AAA). The aim of this study was to further evaluate relationships betweenAAAand inflammatory biomarkers, interleukin- 6 (IL-6), tumour necrosis factor-α (TNF-α), endothelin-1 (ET-1) and soluble u

Context. The first data release from the Gaia mission contains accurate positions and magnitudes for more than a billion sources, and proper motions and parallaxes for the majority of the 2.5 million Hipparcos and Tycho-2 stars. Aims. We describe three essential elements of the initial data treatment leading to this catalogue: the image analysis, the construction of a source list, and the near rea

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release. Meth

Gaia is a cornerstone mission in the science programme of the European Space Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which th

The ESA space astrometry mission Gaia will measure the positions, parallaxes and proper motions of the 1 billion brightest stars on the sky. Expected accuracies are in the 725 as range down to 15 mag and sub-mas accuracies at the faint limit (20 mag). The astrometric data are complemented by low-resolution spectrophotometric data in the 3301000 nm wavelength range and, for the brighter stars, radi

BACKGROUND: Special neck support pillows claiming to improve rest and reduce neck pain are currently being advertised.OBJECTIVE: To test whether neck pillows have any positive effect on neck pain and quality of sleep compared with usual pillows and, if so, to find the optimal characteristics of such a pillow.METHODS: Thirty-seven hospital employees and 18 neck patients were asked to test six neck

Background: The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is among the 100 worst invasive species in the world. As one of the most important crop pests and virus vectors, B. tabaci causes substantial crop losses and poses a serious threat to global food security. Results: We report the 615-Mb high-quality genome sequence of B. tabaci Middle East-Asia Minor 1 (MEAM1), the first genome sequen

Ecosystems can show sudden and persistent changes in state despite only incremental changes in drivers. Such critical transitions are difficult to predict, because the state of the system often shows little change before the transition. Early-warning indicators (EWIs) are hypothesized to signal the loss of system resilience and have been shown to precede critical transitions in theoretical models,

We show in this Letter a novel approach for high-contrast imaging through scattering media by combining structured illumination and Fourier filtering (SIF). To assess the image contrast enhancement at different image spatial frequencies, the modulation transfer function is calculated for four detection schemes: (1) no filtering, (2) Fourier filtering, (3) structured illumination, and (4) SIF filte

We have performed near-field x-ray imaging with simultaneous object and probe reconstruction. By an advanced ptychographic algorithm based on longitudinal and lateral translations, full-field images of nanoscale objects are reconstructed with quantitative contrast values, along with the extended wavefronts used to illuminate the objects. The imaging scheme makes idealizing assumptions on the probe