1,351 research outputs found
Image Based Modeling Technique for Pavement Distress surveys: a Specific Application to Rutting
Image-based modeling (IBM) is a well-known
technique to obtain high quality 3D models based on multi view
images. IBM started being used in several applications such as
inspection, identification of objects and visualization, due to the
user-friendly approach, the low cost and highly automated
technique.
This paper focuses on the investigation of the potential
application of IBM in the diagnosis of road pavement distresses
and in particular rutting. Indeed, the evaluation of the rutting
distress is a fundamental step to define the whole state of a
pavement as demonstrated by the calculation of Present
Serviceability Index (PSI). Currently, the permanent
deformation is measured monitoring visually the rut depth with
the approximations that this procedure involves. Nevertheless,
the exact measure of the rut depth is necessary to evaluate
precisely the cause and the severity of this distress and be
effective in the maintenance and rehabilitation of the pavement
structure.
The objective of this study is to apply the IBM technique on a
laboratory rutted sample, in order to verify the accuracy of the
method in determining the rut depth. To achieve this, a
comparison has been made between the 3D model obtained with
IBM and the one obtained with blue led 3D scan (Artec Spider)
of the same rutted asphalt concrete. The metric accuracy of the
model is then defined and its validity is assessed, in terms of
distress diagnosis
An improved method on stimulated T-lymphocytes to functionally characterize novel and known LDLR mutations.
The main causes of familial hypercholesterolemia (FH) are mutations in LDL receptor (LDLR) gene. Functional studies are necessary to demonstrate the LDLR function impairment caused by mutations and would be useful as a diagnostic tool if they allow discrimination between FH patients and controls. In order to identify the best method to detect LDLR activity, we compared continuous Epstein-Barr virus (EBV)-transformed B-lymphocytes and mitogen stimulated T-lymphocytes. In addition, we characterized both novel and known mutations in the LDLR gene. T-lymphocytes and EBV-transformed B-lymphocytes were obtained from peripheral blood of 24 FH patients and 24 control subjects. Functional assays were performed by incubation with fluorescent LDL followed by flow cytometry analysis. Residual LDLR activity was calculated normalizing fluorescence for the mean fluorescence of controls. With stimulated T-lymphocytes we obtained a better discrimination capacity between controls and FH patients compared with EBV-transformed B-lymphocytes as demonstrated by receiver operating characteristic (ROC) curve analysis (the areas under the curve are 1.000 and 0.984 respectively; P < 0.0001 both). The characterization of LDLR activity through T-lymphocytes is more simple and faster than the use of EBV-transformed B-lymphocytes and allows a complete discrimination between controls and FH patients. Therefore the evaluation of residual LDLR activity could be helpful not only for mutation characterization but also for diagnostic purposes
Successful control of an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K.\ua0pneumoniae sequence type 258 in a neonatal intensive care unit, Italy
This article reports an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) sequence type (ST) 258 in a neonatal intensive care unit (NICU) in Palermo, Italy. KPC-Kp ST258 was detected by an active surveillance culture programme. Between 18th September and 14th November 2012, KPC-Kp was isolated from 10 out of 54 neonates admitted in the outbreak period. No cases of infection were recorded. Male sex was associated with colonization, whereas administration of ampicilline-sulbactam plus gentamicin was protective. Infection control interventions interrupted the spread of KPC-Kp without the need to close the NICU to new admissions. (C) 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved
THE ROLE OF BUTYRIC ACID AS A OPROTECTIVE AGENT AGAINST INFLAMMATORY BOWEL DISEASE
Inflammatory Bowel disease (IBD), such as Crohn's disease and ulcerative colitis, are pathologies characterized by a chronic inflammation of the gastrointestinal tract. Their etiopathogenesis is not yet fully understood. Immune system and heat shock proteins (HSPs) dysfunctions are considered to be among the most likely causes of these diseases. Butyrate is a short-chain fatty acid produced by intestinal microflora. It has a trophic, benefical and protective role in the colonic mucosa, and it also induces changes in Hsp levels and localization. It may therefore be a valuable complementary therapeutic agent when used alongside trraditional drugs (mesalazine and corticosteroids) to treat the production of butyrate in the endoluminal environment may promote clinical remission in IBD patients. Due to these characteristics, there has been keen interest in the use of butyrate as a novel therapeutic supplement in the recent years. The current findings need to be validated through further clinical trials to better define the bbiomolecular dynamics of butyrate in the colonocytes of IBD patients
Synthesis, studies and fuel cell performance of “core–shell” electrocatalysts for oxygen reduction reaction based on a PtNix carbon nitride “shell” and a pyrolyzed polyketone nanoball “core”
This report describes a new class of "core-shell" electrocatalysts for oxygen reduction reaction (ORR) processes for application in Proton Exchange Membrane Fuel Cells (PEMFCs). The electrocatalysts are obtained by supporting a "shell" consisting of PtNix alloy nanoparticles embedded into a carbon nitride matrix (indicated as PtNix-CN) on a "core" of pyrolyzed polyketone nanoballs, labeled 'STp'. ST(p)s are obtained by the sulfonation and pyrolysis of a precursor consisting of XC-72R carbon nanoparticles wrapped by polyketone (PK) fibers. The ST(p)s are extensively characterized in terms of the chemical composition, thermal stability, degree of graphitization and morphology. The "core-shell" ORR electrocatalysts are prepared by the pyrolysis of precursors obtained impregnating the STp "cores" with a zeolitic inorganic-organic polymer electrolyte (Z-IOPE) plastic material. The electrochemical performance of the electrocatalysts in the ORR is tested "in situ" by single fuel cell tests. The interplay between the chemical composition, the degree of graphitization of both PtNix-CN "shell" and STpS "cores", the morphology of the electrocatalysts and the fuel cell performance is elucidated. The most crucial preparation parameters for the optimization of the various features affecting the fuel cell performance of this promising class of ORR electrocatalysts are identified
Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab
MeV-GeV dark matter (DM) is theoretically well motivated but remarkably
unexplored. This Letter of Intent presents the MeV-GeV DM discovery potential
for a 1 m segmented plastic scintillator detector placed downstream of the
beam-dump at one of the high intensity JLab experimental Halls, receiving up to
10 electrons-on-target (EOT) in a one-year period. This experiment
(Beam-Dump eXperiment or BDX) is sensitive to DM-nucleon elastic scattering at
the level of a thousand counts per year, with very low threshold recoil
energies (1 MeV), and limited only by reducible cosmogenic backgrounds.
Sensitivity to DM-electron elastic scattering and/or inelastic DM would be
below 10 counts per year after requiring all electromagnetic showers in the
detector to exceed a few-hundred MeV, which dramatically reduces or altogether
eliminates all backgrounds. Detailed Monte Carlo simulations are in progress to
finalize the detector design and experimental set up. An existing 0.036 m
prototype based on the same technology will be used to validate simulations
with background rate estimates, driving the necessary RD towards an
optimized detector. The final detector design and experimental set up will be
presented in a full proposal to be submitted to the next JLab PAC. A fully
realized experiment would be sensitive to large regions of DM parameter space,
exceeding the discovery potential of existing and planned experiments by two
orders of magnitude in the MeV-GeV DM mass range.Comment: 28 pages, 17 figures, submitted to JLab PAC 4
The Main Results of the Borexino Experiment
The main physical results on the registration of solar neutrinos and the
search for rare processes obtained by the Borexino collaboration to date are
presented.Comment: 8 pages, 8 figgures, To be published as Proceedings of the Third
Annual Large Hadron Collider Physics Conference, St. Petersburg, Russia, 201
Performance of prototypes for the ALICE electromagnetic calorimeter
The performance of prototypes for the ALICE electromagnetic sampling
calorimeter has been studied in test beam measurements at FNAL and CERN. A
array of final design modules showed an energy resolution of about
11% / 1.7 % with a uniformity of the response
to electrons of 1% and a good linearity in the energy range from 10 to 100 GeV.
The electromagnetic shower position resolution was found to be described by 1.5
mm 5.3 mm /. For an electron identification
efficiency of 90% a hadron rejection factor of was obtained.Comment: 10 pages, 10 figure
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