7,331 research outputs found
The Elephant Quantum Walk
We explore the impact of long-range memory on the properties of a family of
quantum walks in a one-dimensional lattice and discrete time, which can be
understood as the quantum version of the classical "Elephant Random Walk"
non-Markovian process. This Elephant Quantum Walk is robustly superballistic
with the standard deviation showing a constant exponent, , whatever the quantum coin operator, on which the diffusion coefficient is
dependent. On the one hand, this result indicates that contrarily to the
classical case, the degree of superdiffusivity in quantum non- Markovian
processes of this kind is mainly ruled by the extension of memory rather than
other microscopic parameters that explicitly define the process. On the other
hand, these parameters reflect on the diffusion coefficient.Comment: 4 figures, any comments is welcome. Accepted in PR
Fertility preservation in ovarian tumours
A considerable number of patients with a cancer diagnosis are of childbearing age and have not satisfied their desire for a family. Despite ovarian cancer (OC) usually occurring in older patients, 3%–14% are diagnosed at a fertile age with the overall 5-year survival rate being 91.2% in women ≤44 years of age when it is found at 1A–B stage. In this scenario, testing the safety and the efficacy of fertility sparing strategies in OC patients is very important overall in terms of quality of life. Unfortunately, the lack of randomised trials to validate conservative approaches does not guarantee the safety of fertility preservation strategies. However, evidence-based data from descriptive series suggest that in selected cases, the preservation of the uterus and at least one part of the ovary does not lead to a high risk of relapse. This conservative surgery helps to maintain organ function, giving patients of childbearing age the possibility to preserve their fertility. We hereby analysed the main evidence from the international literature on this topic in order to highlight the selected criteria for conservative management of OC patients, including healthy BRCA mutations carriers
The inhibition by hydrocortisone of prostaglandin biosynthesis in rat peritoneal leucocytes is correlated with intracellular macrocortin levels
Hydrocortisone inhibits prostaglandin generation by rat peritoneal leucocytes by releasing the polypeptide phospholipase inhibitor, macrocortin. The susceptibility of these cells to hydrocortisone is directly correlated with their intracellular macrocortin content. Cells depleted of the peptide by prior incubation with steroid cannot respond to the steroid, until a fresh intracellular store has been synthesized. In vitro, this process requires 4-5 h. Cells remain sensitive to the inhibitory action of the peptide at all times
Report on advances for pediatricians in 2018: allergy, cardiology, critical care, endocrinology, hereditary metabolic diseases, gastroenterology, infectious diseases, neonatology, nutrition, respiratory tract disorders and surgery.
This review reported notable advances in pediatrics that have been published in 2018. We have highlighted progresses in allergy, cardiology, critical care, endocrinology, hereditary metabolic diseases, gastroenterology, infectious diseases, neonatology, nutrition, respiratory tract disorders and surgery. Many studies have informed on epidemiologic observations. Promising outcomes in prevention, diagnosis and treatment have been reported. We think that advances realized in 2018 can now be utilized to ameliorate patient car
Characterisation of AMS H35 HV-CMOS monolithic active pixel sensor prototypes for HEP applications
Monolithic active pixel sensors produced in High Voltage CMOS (HV-CMOS)
technology are being considered for High Energy Physics applications due to the
ease of production and the reduced costs. Such technology is especially
appealing when large areas to be covered and material budget are concerned.
This is the case of the outermost pixel layers of the future ATLAS tracking
detector for the HL-LHC. For experiments at hadron colliders, radiation
hardness is a key requirement which is not fulfilled by standard CMOS sensor
designs that collect charge by diffusion. This issue has been addressed by
depleted active pixel sensors in which electronics are embedded into a large
deep implantation ensuring uniform charge collection by drift. Very first small
prototypes of hybrid depleted active pixel sensors have already shown a
radiation hardness compatible with the ATLAS requirements. Nevertheless, to
compete with the present hybrid solutions a further reduction in costs
achievable by a fully monolithic design is desirable. The H35DEMO is a large
electrode full reticle demonstrator chip produced in AMS 350 nm HV-CMOS
technology by the collaboration of Karlsruher Institut f\"ur Technologie (KIT),
Institut de F\'isica d'Altes Energies (IFAE), University of Liverpool and
University of Geneva. It includes two large monolithic pixel matrices which can
be operated standalone. One of these two matrices has been characterised at
beam test before and after irradiation with protons and neutrons. Results
demonstrated the feasibility of producing radiation hard large area fully
monolithic pixel sensors in HV-CMOS technology. H35DEMO chips with a substrate
resistivity of 200 cm irradiated with neutrons showed a radiation
hardness up to a fluence of ncm with a hit efficiency of
about 99% and a noise occupancy lower than hits in a LHC bunch
crossing of 25ns at 150V
Performance of the diamond active target prototype for the PADME experiment at the DANE BTF
The PADME experiment at the DANE Beam-Test Facility (BTF) is designed
to search for the gauge boson of a new interaction in the process
ee+, using the intense positron beam hitting a
light target. The , usually referred as dark photon, is assumed to
decay into invisible particles of a secluded sector and it can be observed by
searching for an anomalous peak in the spectrum of the missing mass measured in
events with a single photon in the final state. The measurement requires the
determination of the 4-momentum of the recoil photon, performed by a
homogeneous, highly segmented BGO crystals calorimeter. A significant
improvement of the missing mass resolution is possible using an active target
capable to determine the average position of the positron bunch with a
resolution of less than 1 mm. This report presents the performance of a real
size PADME active target made of a thin (50 m) diamond
sensor, with graphitic strips produced via laser irradiation on both sides. The
measurements are based on data collected in a beam test at the BTF in November
2015.Comment: 7 pages, 10 figure
Anatomy of the AGN in NGC 5548: V. A clear view of the X-ray narrow emission lines
Context. Our consortium performed an extensive multi-wavelength campaign of
the nearby Seyfert 1 galaxy NGC 5548 in 2013-14. The source appeared unusually
heavily absorbed in the soft X-rays, and signatures of outflowing absorption
were also present in the UV. He-like triplets of neon, oxygen and nitrogen, and
radiative recombination continuum (RRC) features were found to dominate the
soft X-ray spectrum due to the low continuum flux.
Aims. Here we focus on characterising these narrow emission features using
data obtained from the XMM-Newton RGS (770 ks stacked spectrum).
Methods. We use SPEX for our initial analysis of these features.
Self-consistent photoionisation models from Cloudy are then compared with the
data to characterise the physical conditions of the emitting region.
Results. Outflow velocity discrepancies within the O VII triplet lines can be
explained if the X-ray narrow-line region (NLR) in NGC 5548 is absorbed by at
least one of the six warm absorber components found by previous analyses. The
RRCs allow us to directly calculate a temperature of the emitting gas of a few
eV ( K), favouring photoionised conditions. We fit the data with a
Cloudy model of log erg cm s, log cm and log v km s for the emitting
gas; this is the first time the X-ray NLR gas in this source has been modelled
so comprehensively. This allows us to estimate the distance from the central
source to the illuminated face of the emitting clouds as pc,
consistent with previous work.Comment: Accepted by A&A, 15 pages, 6 figure
Fotemustine plus etoposide, cytarabine and melphalan (FEAM) as a new conditioning regimen for lymphoma patients undergoing auto-SCT: A multicenter feasibility study
BEAM is a widely used conditioning regimen for relapsed/refractory lymphoma patients undergoing auto-SCT. We conducted a multicenter study with an alternative regimen (fotemustine plus etoposide, cytarabine and melphalan (FEAM)) in which BCNU was substituted by the chloroethylnitrosourea fotemustine (FTM). Eighty-four patients with relapsed/refractory Hodgkin's (n20) and non-Hodgkin's lymphoma (n64) were conditioned with a FEAM regimen (FTM 150 mg/m 2 on days -7, -6, etoposide 200 mg/m 2 and cytarabine 400 mg/m 2 on days -5, -4, -3, -2 and melphalan 140 mg/m 2 on day -1). Patients were evaluated for toxicity and engraftment parameters. Median times to neutrophil (500 × 10 9 /l) and plt (20 000 × 10 9 /l) engraftment were 11 and 13 days, respectively. Grade 3 mucositis occurred in 19 patients (23%), while G3 nausea/vomiting and G3 diarrhea were observed in 13 (15%) and 6 (7%) patients, respectively. No severe hepatic, renal or pulmonary toxicity was detected. Seven patients (7%) experienced G4 mucositis, while no other G4 toxicities or unexpected adverse events of any grade were recorded. Transplant-related mortality was 2.4%. We conclude that a FEAM regimen is feasible and safe. Although toxicity and engraftment times compared favorably with BEAM, longer follow-up is needed to evaluate fully its efficacy and long-term safety. © 2010 Macmillan Publishers Limited All rights reserved
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