Search results for "current"
showing 10 items of 2224 documents
Satellite-derived land surface temperature: Current status and perspectives
2013
Abstract Land surface temperature (LST) is one of the key parameters in the physics of land surface processes from local through global scales. The importance of LST is being increasingly recognized and there is a strong interest in developing methodologies to measure LST from space. However, retrieving LST is still a challenging task since the LST retrieval problem is ill-posed. This paper reviews the current status of selected remote sensing algorithms for estimating LST from thermal infrared (TIR) data. A brief theoretical background of the subject is presented along with a survey of the algorithms employed for obtaining LST from space-based TIR measurements. The discussion focuses on TI…
Proton spin and the cheshire cat principle
1991
Abstract We discuss the proton matrix element of the flavor-singlet axial current (FSAC), often referred to as proton spin, in terms of the chiral bag model with due account of the axial anomaly and quantum number fractionation. We conclude that the contribution due to gluons is significant for large bag radii and that it is crucial in order to establish the Cheshire cat principle.
The Current State of Phyto-Coenological Research in the “Iron Gates” Danube Gorge (Banat, Romania)
2014
Abstract The author of the study writes a concise history of the phyto-coenological research conducted previously in the Danube Gorge; he notes the papers and the respective publishing years for the botanists who contributed with research to the knowledge of the cormophyte vegetation along the aforementioned sector of the Danube River. 55 important papers are highlighted, authored by fifty-four specialists in the years 1931-2006.
Sorafenib in advanced hepatocellular carcinoma
2008
none 25 BACKGROUND: No effective systemic therapy exists for patients with advanced hepatocellular carcinoma. A preliminary study suggested that sorafenib, an oral multikinase inhibitor of the vascular endothelial growth factor receptor, the platelet-derived growth factor receptor, and Raf may be effective in hepatocellular carcinoma. METHODS: In this multicenter, phase 3, double-blind, placebo-controlled trial, we randomly assigned 602 patients with advanced hepatocellular carcinoma who had not received previous systemic treatment to receive either sorafenib (at a dose of 400 mg twice daily) or placebo. Primary outcomes were overall survival and the time to symptomatic progression. Seconda…
Observation of Kuznetsov-Ma soliton dynamics in optical fibre
2012
International audience; The nonlinear Schro¨dinger equation (NLSE) is a central model of nonlinear science, applying to hydrodynamics, plasma physics, molecular biology and optics. The NLSE admits only few elementary analytic solutions, but one in particular describing a localized soliton on a finite background is of intense current interest in the context of understanding the physics of extreme waves. However, although the first solution of this type was the Kuznetzov-Ma (KM) soliton derived in 1977, there have in fact been no quantitative experiments confirming its validity. We report here novel experiments in optical fibre that confirm the KM soliton theory, completing an important serie…
Optical Gating of Photosensitive Synthetic Ion Channels
2011
4-oxo-4-(pyren-4-ylmethoxy) butanoic acid is used as a photolabile protecting group to show the optical gating of nanofluidic devices based on synthetic ion channels. The inner surface of the channels is decorated with monolayers of photolabile hydrophobic molecules that can be removed by irradiation, which leads to the generation of hydrophilic groups. This process can be exploited in the UV-light-triggered permselective transport of ionic species in aqueous solution through the channels. The optical gating of a single conical nanochannel and multichannel polymeric membranes is characterised experimentally and theoretically by means of current-voltage and selective permeation measurements,…
On the severity of economic downturns: Lessons from cross-country evidence
2012
Abstract We measure the severity of recessions as a function of their amplitude and duration. Within a quantile regression framework, we assess what causes economic downturns to be more or less severe. We find that the most severe downturns have striking similarities regarding cumulated domestic credit and large current account deficits.
Runoff Generation in Badlands
2019
Capítulo 5.
The Results of Changing the Current Solution Concept of Universal Motor Gear Reducers with Helical Gears
2021
By analysing and comparing the existing solutions of universal gear reducers with helical gears of the leading manufacturers, it can be noticed the effort to increase the load capacity of the gear reducer within the same axis height. In this way, the manufacturers can offer smaller (cheaper) gear reducers, as well as to simultaneously increase the values of the largest gear ratios. This concept enables the offer of lower-stage (cheaper) gear reducers with higher gear ratios in certain segments of gear ratios. By these efforts, it is reached the maximum, but the further increase is possible only by changing the current concept of universal gear drives. Within this paper, it is given an overv…
Updated Search for the Flavor-Changing Neutral-Current Decay D^0 \to {\mu} + {\mu}-
2010
We report on a search for the flavor-changing neutral-current decay D0 \to {\mu}+ {\mu}- in pp collisions at \surd s = 1.96 TeV using 360 pb-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D0 candidates in the {\mu}+ {\mu}-, {\pi}+{\pi}-, and K-{\pi}+ decay modes. We use the Cabibbo-favored D0 \to K-{\pi}+ channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D0 \to{\pi}+ {\pi}- channel for normalization. We set an upper limit on the branching fraction (D0 --> {\mu}+ {\mu}-) < 2.1 E-7 (3.0 E-7) at the 90% (95%) confidence level.