647 research outputs found
Chromospherically active stars in the ROTSE-1 database: paper 6. Variables 126 - 149
Another 24 new chromospherically active stars are presented, which were found in the ROTSE-1 database: GSC 02268-00394, GSC 01224-00894, GSC 00648-00579, GSC 02865-01987, GSC 01851-01202, GSC 00124-00551, GSC 00150-01109, GSC 01339-00572, GSC 02968-01511, GSC 03005-00885, GSC 01083-00698, GSC 03941-00354, GSC 04450-00134, GSC 05163-01764, GSC 01095-00848, GSC 04459-00659, USNO A2.0 1275-14029063, GSC 04247-00903, GSC 01656-01276, GSC 02197-01430, GSC 02227-01294, GSC 04480-00965, GSC 01159-00245, GSC 02237-01574. For one of these stars (GSC 00124-00551), further observations were made using a TeleView 509/5.0 telescope with a CCD camera SIGMA1603 and IR-cutting filter in Velden, Germany
Determination of arsenic in agricultural soil samples using High-resolution continuum source graphite furnace atomic absorption spectrometry and direct solid sample analysis
The authors are grateful to the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for financial support and scholarships. BW had a research scholarship from CNPq, Processo No. 303526/2016-5. The authors are also grateful to Analytik Jena for the donation of the HR-CS GF AAS Model contrAA 600 and for financial support.Peer reviewedPostprin
Istraživanje nečiste i čiste (100) površine vanadija STM-om
Scanning tunneling microscopy is used to characterize different states of the V(100) surface during the cleaning procedure in an ultrahigh vacuum apparatus, starting with the "as received" sample and finishing with an almost perfectly clean surface. We show, for the first time, STM images of the clean V(100) surface and with atomic resolution.Primijenili smo skenirajući tunelirajući mikroskop (STM) za topografsku karakterizaciju površine V(100) prije i tijekom čišćenja u aparaturi za ultravisok vakuum, počevši s “dobivenim” uzorkom i nakon pojedinih postupaka čišćenja. Po prvi puta se pokazuju slike potpuno čiste površine V(100) s atomskim razlučivanjem, snimljene STM-om
Istraživanje nečiste i čiste (100) površine vanadija STM-om
Scanning tunneling microscopy is used to characterize different states of the V(100) surface during the cleaning procedure in an ultrahigh vacuum apparatus, starting with the "as received" sample and finishing with an almost perfectly clean surface. We show, for the first time, STM images of the clean V(100) surface and with atomic resolution.Primijenili smo skenirajući tunelirajući mikroskop (STM) za topografsku karakterizaciju površine V(100) prije i tijekom čišćenja u aparaturi za ultravisok vakuum, počevši s “dobivenim” uzorkom i nakon pojedinih postupaka čišćenja. Po prvi puta se pokazuju slike potpuno čiste površine V(100) s atomskim razlučivanjem, snimljene STM-om
Efficient HTS DC- Cable for Power Distribution in Hybrid-Electric Aircraft
With respect to a substantial reduction of greenhouse gas emission, noise reduction and combustible consumption in aircraft an increasing interest in hybrid-electric propulsion systems has emerged in the last years. In the frame of a German research project we actually develop a HTS superconducting busbar system for DC currents able to join the different components as generator, motors and battery systems on the plane.
Main features of this busbar system are large currents at moderate voltages and in particular low ohmic contacts, including T-type, Y-type and cross connections between system segments, this with a minimization of outer dimensions and weight. The two-pole cable consists of two stacks of REBCO tapes. Compensation of Lorentz forces between the two poles, compensation of thermal length changes and sufficient electric insulation are the major challenges. We will present details of the cable design and first test results on a lab-scale cable demonstrator
Performance of Drift-Tube Detectors at High Counting Rates for High-Luminosity LHC Upgrades
The performance of pressurized drift-tube detectors at very high background
rates has been studied at the Gamma Irradiation Facility (GIF) at CERN and in
an intense 20 MeV proton beam at the Munich Van-der-Graaf tandem accelerator
for applications in large-area precision muon tracking at high-luminosity
upgrades of the Large Hadron Collider (LHC). The ATLAS muon drifttube (MDT)
chambers with 30 mm tube diameter have been designed to cope with and neutron
background hit rates of up to 500 Hz/square cm. Background rates of up to 14
kHz/square cm are expected at LHC upgrades. The test results with standard MDT
readout electronics show that the reduction of the drift-tube diameter to 15
mm, while leaving the operating parameters unchanged, vastly increases the rate
capability well beyond the requirements. The development of new small-diameter
muon drift-tube (sMDT) chambers for LHC upgrades is completed. Further
improvements of tracking efficiency and spatial resolution at high counting
rates will be achieved with upgraded readout electronics employing improved
signal shaping for high counting rates
Heat Attenuation and Nutrient Delivery by Localized Upwelling Avoided Coral Bleaching Mortality in Northern Galapagos During 2015/2016 ENSO
Despite a very strong El Niño Southern Oscillation in 2015/2016, no coral mortality associated with bleaching was observed at the northern Galapagos (Ecuador) Islands of Darwin and Wolf. From March 2016 to March 2018, coral cover and health as well as water chemistry (NO3− and PO43−) and temperature were recorded. A marked heat anomaly reached 30 °C at Wolf in February 2016, but peak temperatures were attenuated after 2 d by a 4 °C drop. Temperature patterns at three depths (10, 15, and 20 m) and a subsequent and persistent phytoplankton bloom suggest topographically driven upwelling as the source of colder water and dissolved inorganic nutrients—both of which helped corals endure the heating episode. Consequently, no mortality and only partial bleaching were recorded in March 2016. Partially bleached corals contained numerous healthy zooxanthellae in deeper tissue layers. A continuous temperature record from 2012 to 2014 suggests that such upwelling events are common, inducing temperature fluctuations of up to 6 °C within 24 h during the observation period. Events at Wolf in 2016 suggest local upwelling reduced coral stress by relieving heat and by delivering nutrients required by corals to retain their regular temperature tolerance
Treatment of Infantile Spasm Syndrome: Update from the Interdisciplinary Guideline Committee Coordinated by the German-Speaking Society of Neuropediatrics
OBJECTIVES
The manuscript serves as an update on the current management practices for infantile spasm syndrome (ISS). It includes a detailed summary of the level of current evidence of different treatment options for ISS and gives recommendations for the treatment and care of patients with ISS.
METHODS
A literature search was performed using the Cochrane and Medline Databases (2014 to July 2020). All studies were objectively rated using the Scottish Intercollegiate Guidelines Network. For recommendations, the evidence from these studies was combined with the evidence from studies used in the 2014 guideline.
RECOMMENDATIONS
If ISS is suspected, electroencephalography (EEG) should be performed within a few days and, if confirmed, treatment should be initiated immediately. Response to first-line treatment should be evaluated clinically and electroencephalographically after 14 days. The preferred first-line treatment for ISS consists of either hormone-based monotherapy (AdrenoCorticoTropic Hormone [ACTH] or prednisolone) or a combination of hormone and vigabatrin. Children with tuberous sclerosis complex and those with contraindications against hormone treatment should be treated with vigabatrin. If first-line drugs are ineffective, second-line treatment options such as ketogenic dietary therapies, sulthiame, topiramate, valproate, zonisamide, or benzodiazepines should be considered. Children refractory to drug therapy should be evaluated early for epilepsy surgery, especially if focal brain lesions are present. Parents should be informed about the disease, the efficacy and adverse effects of the medication, and support options for the family. Regular follow-up controls are recommended
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