156 research outputs found
Effect of modification of peanut conglutin on IgE and T cell reactivity in adults with peanut allergy
A superburst from 4U 1254-690
We report the detection with the BeppoSAX Wide Field Cameras of a superburst
from 4U 1254-690. The superburst is preceded by a normal type-I X-ray burst,
has a decay time that is the longest of all eight superbursts detected so far
and a peak luminosity that is the lowest. Like for the other seven superbursts,
the origin is a well-known type-I X-ray burster with a persistent luminosity
level close to one tenth of the Eddington limit. Based on WFC data of all
persistently bright X-ray bursters, the average rate of superbursts is
0.51+/-0.25 per year per persistently bright X-ray burster. Some systems may
have higher superburst rates. For all superbursters, we present evidence for a
pure helium layer which is burnt in an unstable as well as a stable manner.Comment: Accepted by A&A Letter
Reservoir characterisation using process-response simulations: the Lower Cretaceous Rijn Field, West Netherlands Basin
Dental implants in dentate primary and secondary Sjögren's syndrome patients:A multicenter prospective cohort study
Objectives: To prospectively assess the clinical performance and patient-reported outcomes of dental implants in dentate patients with primary and secondary Sjögren's syndrome (pSS and sSS, respectively) compared to patients without SS. Materials and Methods: Thirty-seven implants were placed in 17 patients with pSS/sSS and 26 implants in 17 non-SS patients to replace missing (pre)molars. Clinical performance, marginal bone-level changes, patient satisfaction, and oral health-related quality of life (OHRQoL) were assessed at 1 (T1), 6 (T6), 12 (T12), and 18 (T18) months after placement of the superstructure. Marginal bone-level changes were measured on standardized dental radiographs. Clinical parameters included implant and crown survival, plaque, bleeding and gingival indices, and probing depth. Patient satisfaction and OHRQoL were assessed with validated questionnaires. Results: Implant survival at T18 was 100% in the patients with pSS/sSS and 96.2% in the non-SS group. Mean marginal bone loss at T18 did not differ between patients with pSS/sSS and non-SS patients, 1.10 ± 1.04 and 1.04 ± 0.75 mm, respectively (p =.87). Clinical performance was good with no differences between the groups for all outcome measures (p >.05). OHRQoL in patients with pSS/sSS had improved significantly after placement of implant supported crowns at all measuring moments compared to baseline (p <.05). Nevertheless, patient satisfaction and OHRQoL remained significantly higher for patients without SS at all measuring moments (p <.05). Conclusion: Dental implants can be successfully applied in dentate patients with pSS/sSS and have a positive effect on OHRQoL
Development of ranking system for higher education of Ukraine
A system of determination of university ranking in Ukraine was developed based on the creation of the corresponding methods adequate to the structure, peculiarities and conditions of the Ukrainian universities functioning. A complex of organizational and program-technical means was proposed for collection of the necessary data and determination of university rankings. For specialists in the field of higher education management, those seeking for higher education and employers.Разработана система определения рейтингов университетов Украины, которая основывается на создании определенной методики, адекватной структуре, особенностям и условиям функционирования отечественной высшей школы. Предложен комплекс организационных и программно-технических средств, который применяется при сборе данных и определении оценок рейтингов университетов для специалистов в области управления высшим образованием, а также желающих получить образование и работодателей.Розроблено систему визначення рейтингів університетів України, яка ґрунтується на створенні відповідної методики, адекватної до структури, особливостей та умов функціонування вітчизняної вищої школи. Запропоновано комплекс організаційних і програмно-технічних засобів, що застосовується при збиранні даних та визначенні оцінок рейтингів університетів для фахівців у галузі управління вищою освітою, а також бажаючих отримати освіту та роботодавців
INTEGRAL survey of the Cassiopeia region in hard X rays
We report on the results of a deep 1.6 Ms INTEGRAL observation of the
Cassiopeia region performed from December 2003 to February 2004. Eleven sources
were detected with the imager IBIS-ISGRI at energies above 20 keV, including
three new hard X-ray sources. Most remarkable is the discovery of hard X-ray
emission from the anomalous X-ray pulsar 4U 0142+61, which shows emission up to
\~150 keV with a very hard power-law spectrum with photon index Gamma = 0.73
+/- 0.17. We derived flux upper limits for energies between 0.75 MeV and 30 MeV
using archival data from the Compton telescope COMPTEL. In order to reconcile
the very hard spectrum of 4U 0142+61 measured by INTEGRAL with the COMPTEL
upper limits, the spectrum has to bend or break between ~75 keV and ~750 keV.
1E 2259+586, another anomalous X-ray pulsar in this region, was not detected.
INTEGRAL and COMPTEL upper limits are provided. The new INTEGRAL sources are
IGR J00370+6122 and IGR J00234+6144. IGR J00370+6122 is a new supergiant X-ray
binary with an orbital period of 15.665 +/- 0.006 days, derived from RXTE
All-Sky Monitor data. Archival BeppoSAX Wide-Field Camera data yielded four
more detections. IGR J00234+6144 still requires a proper identification. Other
sources for which INTEGRAL results are presented are high-mass X-ray binaries
2S 0114+650, Gamma~Cas, RX J0146.9+6121 and 4U 2206+54, intermediate polar V709
Cas and 1ES 0033+595, an AGN of the BL-Lac type. For each of these sources the
hard X-ray spectra are fitted with different models and compared with earlier
published results.Comment: 16 pages, 13 figures, accepted for publication in A&
BeppoSAX-WFC monitoring of the Galactic Center region
We review the results obtained with the Galactic center campaigns of the
BeppoSAX Wide Field X-ray Cameras (WFCs). This pertains to the study of
luminous low-mass X-ray binaries (LMXBs). When pointed at the Galactic center,
the WFC field of view contains more than half of the Galactic LMXB population.
The results exemplify the excellent WFC capability to detect brief X-ray
transients. Firstly, the WFCs expanded the known population of Galactic
thermonuclear X-ray bursters by 50%. At least half of all LMXBs are now
established to burst and, thus, to contain a neutron star as compact accretor
rather than a black hole candidate. We provide a complete list of all 76
currently known bursters, including the new case 1RXS J170854.4-321857.
Secondly, the WFCs have uncovered a population of weak transients with peak
luminosities up to ~10^37 erg/s and durations from days to weeks. One is the
first accretion-powered millisecond pulsar SAX J1808.4-3658. Thirdly, the WFCs
contributed considerably towards establishing that nearly all (12 out of 13)
luminous low-mass X-ray binaries in Galactic globular clusters contain neutron
stars rather than black holes. Thus, the neutron star to black hole ratio in
clusters differs from that in the Galactic disk at a marginal confidence level
of 97%.Comment: 10 pages 6 figures, to appear in Proc. "The Restless High-Energy
Universe" (2nd BeppoSAX Symposium), eds. E.P.J. van den Heuvel, J.J.M. in 't
Zand & R.A.M.J. Wijers, Nucl. Instrum. Meth. B Suppl. Se
First superburst from a classical low-mass X-ray binary transient
We report the analysis of the first superburst from a transiently accreting
neutron star system with the All-Sky Monitor (ASM) on the Rossi X-ray Timing
Explorer. The superburst occurred 55 days after the onset of an accretion
outburst in 4U 1608-522. During that time interval, the accretion rate was at
least 7% of the Eddington limit. The peak flux of the superburst is 22 to 45%
of the Eddington limit, and its radiation energy output is between 4e41 and
9e41 erg for a distance of 3.2 kpc. Fits of cooling models to the superburst
light curve indicate an ignition column depth between 1.5e12 and 4.1e12 g/cm2.
Extrapolating the accretion history observed by the ASM, we derive that this
column was accreted over a period of 26 to 72 years. The superburst
characteristics are consistent with those seen in other superbursting low-mass
X-ray binaries. However, the transient nature of the hosting binary presents
significant challenges for superburst theory, requiring additional ingredients
for the models. The carbon that fuels the superburst is thought to be produced
mostly during the accretion outbursts and destroyed in the frequent type-I
X-ray bursts. Mixing and sedimentation of the elements in the neutron star
envelope may significantly influence the balance between the creation and
destruction of carbon. Furthermore, predictions for the temperature of the
neutron star crust fail to reach the values required for the ignition of carbon
at the inferred column depth.Comment: 12 pages, 8 figures, accepted for publication in A&
Detection of the energetic pulsar PSR B1509-58 and its pulsar wind nebula in MSH 15-52 using the Fermi-Large Area Telescope
We report the detection of high energy gamma-ray emission from the young and
energetic pulsar PSR B150958 and its pulsar wind nebula (PWN) in the
composite supernova remnant SNR G320.4-1.2 (aka MSH 15-52). Using 1 year of
survey data with the Fermi-Large Area Telescope (LAT), we detected pulsations
from PSR B1509-58 up to 1 GeV and extended gamma-ray emission above 1 GeV
spatially coincident with the PWN. The pulsar light curve presents two peaks
offset from the radio peak by phases 0.96 0.01 and 0.33 0.02. New
constraining upper limits on the pulsar emission are derived below 1 GeV and
confirm a severe spectral break at a few tens of MeV. The nebular spectrum in
the 1 - 100 GeV energy range is well described by a power-law with a spectral
index of (1.57 0.17 0.13) and a flux above 1 GeV of (2.91
0.79 1.35) 10^{-9} cm^{-2} s^{-1}. The first errors represent the
statistical errors on the fit parameters, while the second ones are the
systematic uncertainties. The LAT spectrum of the nebula connects nicely with
Cherenkov observations, and indicates a spectral break between GeV and TeV
energies.Comment: 14 pages, 6 figures, accepted for publication by Ap
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