1,755 research outputs found
Sensitivity Analysis and Cross Sections Data Adjustment for Multigroup Transport and Diffusion
Uncertainties in basic nuclear data and other quantities involved in the characterization of an experiment affect the accuracy of the results when the respective experiment is modelled. The impact of these uncertainties on computed responses can be assessed by combining the sensitivities of these responses to the input parameters with data uncertainties and covariances. Furthermore, best estimates of both the input parameters and recomputed responses, with reduced uncertainties, can be obtained by using data assimilation and adjustment procedures. This paper reports the results of using the data adjustment methodology in conjunction with the well-known Godiva experiment and a partial set of uncertainties from the ZZ-COV-15 library for U-235 and U-238, together with sensitivities computed with APOLLO transport code by the Adjoint Sensitivity Analysis Procedure, to obtain best-estimate values for the k eigenvalue of the system, with reduced uncertainties. In parallel, sensitivities were also computed using COBAYA diffusion code, compared with those produced by APOLLO, and then employed in the adjustment formalism to obtain the adjusted k eigenvalue and its corresponding reduced uncertainty
Absolute calibration of the LOPES antenna system
Radio emission in extensive air showers arises from an interaction with the
geomagnetic field and is subject of theoretical studies. This radio emission
has advantages for the detection of high energy cosmic rays compared to
secondary particle or fluorescence measurement methods. Radio antennas like the
LOPES30 antenna system are suited to investigate this emission process by
detecting the radio pulses. The characteristic observable parameters like
electric field strength and pulse length require a calibration which was done
with a reference radio source resulting in an amplification factor representing
the system behavior in the environment of the KASCADE-Grande experiment.
Knowing the amplification factor and the gain of the LOPES antennas LOPES30 is
calibrated absolutely for systematic analyses of the radio emission.Comment: 5 pages, Proceedings of International Workshop on Acoustic and Radio
EeV Neutrino detection Activities: ARENA, May 17-19, 2005, DESY Zeuthe
Mining the ESO WFI and INT WFC archives for known Near Earth Asteroids. Mega-Precovery software
The ESO/MPG WFI and the INT WFC wide field archives comprising 330,000 images
were mined to search for serendipitous encounters of known Near Earth Asteroids
(NEAs) and Potentially Hazardous Asteroids (PHAs). A total of 152 asteroids (44
PHAs and 108 other NEAs) were identified using the PRECOVERY software, their
astrometry being measured on 761 images and sent to the Minor Planet Centre.
Both recoveries and precoveries were reported, including prolonged orbital arcs
for 18 precovered objects and 10 recoveries. We analyze all new opposition data
by comparing the orbits fitted before and after including our contributions. We
conclude the paper presenting Mega-Precovery, a new online service focused on
data mining of many instrument archives simultaneously for one or a few given
asteroids. A total of 28 instrument archives have been made available for
mining using this tool, adding together about 2.5 million images forming the
Mega-Archive.Comment: Accepted for publication in Astronomische Nachrichten (Sep 2012
Radioelectric Field Features of Extensive Air Showers Observed with CODALEMA
Based on a new approach to the detection of radio transients associated with
extensive air showers induced by ultra high energy cosmic rays, the
experimental apparatus CODALEMA is in operation, measuring about 1 event per
day corresponding to an energy threshold ~ 5. 10^16 eV. Its performance makes
possible for the first time the study of radio-signal features on an
event-by-event basis. The sampling of the magnitude of the electric field along
a 600 meters axis is analyzed. It shows that the electric field lateral spread
is around 250 m (FWHM). The possibility to determine with radio both arrival
directions and shower core positions is discussed.Comment: Accepted for publication in Astroparticle Physic
Primary and secondary prevention to effectively reduce the risk of bisphosphonate-related osteonecrosis of the jaw in patients with bone metastases .
Background
Bone is one of the most frequent sites of metastasis in patients with advanced cancer. Nearly all patients with myeloma, 65–75%
of patients with prostate or breast cancer, and 30–40% of patients with lung cancer or other solid tumors, eventually develop bone
metastases. Bisphosphonates (BP), particularly zoledronic acid and denosumab, were demonstrated to effectively reduce skeletal
complications in patients with bone metastases. However, bisphosphonate-related osteonecrosis of the jaw (BRONJ) can occur
spontaneously, favored by dental extraction, dental implant surgery, or denture wearing. The purpose of this study was to
underline the role of dental prevention as an effective tool to reduce the risk of BRONJ.
Material and methods
BRONJ was identified with the standardized query “osteonecrosis” among all data from patients treated at Modena Cancer
Center from 2005 to 2016. For each case, demographic and medical information were analyzed, as well as data about notification
(year of occurrence, outcome), type and duration of BP exposure, and associated risk factors (dento-alveolar surgery,
chemotherapy, antiangiogenics). Data were differently analyzed taking into account the implementation of a Dental Prevention
Service in patients who are candidates for BP therapy.Results
Among 1663 patients treated with BP, 63 cases of BRONJ were identified (3.8%). 44 female and 19 men with a median age of 69
years (range 47-90 years), have been treated with BP for bone metastases from breast cancer (54%), hematologic malignancy
(21%), prostate cancer (13%), renal cancer (5%), lung cancer (2%) and other tumors (5%). 15 maxillae and 48 mandibles were
involved. The trigger event was a dental extraction in 29% of the cases, being spontaneously the other 71%. The median time to
BRONJ was 28 months (range 1-89.1 months) from the first dose of BP, and 25 was the mean number of BP doses administered
before BRONJ. Overall, a preliminary odontoiatric evaluation was performed in only 14 cases (22%). All but one of these
dentistry opinions were obtained after 2010 when the Dental Prevention Service was created, which is a drop out of the risk of
BRONJ from 4.1 to 1.9%.
Conclusions.
Prevention of the BRONJ is critical in in bone metastatic patients. The incidence of BRONJ over time can drop to 1.9% when
primary and secondary prevention measures are implemented in routine clinical practice
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