10,008 research outputs found
Event-Related Potentials during a Gambling Task in Young Adults with Attention-Deficit/Hyperactivity Disorder.
Attention-deficit hyperactivity disorder (ADHD) is characterized by deficits in executive functions and decision making during childhood and adolescence. Contradictory results exist whether altered event-related potentials (ERPs) in adults are associated with the tendency of ADHD patients toward risky behavior. Clinically diagnosed ADHD patients ( javax.xml.bind.JAXBElement@5fb8b0ff = 18) and healthy controls ( javax.xml.bind.JAXBElement@76b3b68b = 18), aged between 18 and 29 (median 22 Yo), were screened with the Conners' Adult ADHD Rating Scales and assessed by the Mini-International Neuropsychiatric Interview, adult ADHD Self-Report Scale, and by the 60-item HEXACO Personality Inventory. The characteristic personality traits of ADHD patients were the high level of impulsiveness associated with lower values of agreeableness. All participants performed a probability gambling task (PGT) with two frequencies of the feedback information of the outcome. For each trial, ERPs were triggered by the self-paced trial onset and by the gamble selection. After trial onset, N2-P3a ERP component associated with the attentional load peaked earlier in the ADHD group than in controls. An N500 component related to the feedback frequency condition after trial onset and an N400-like component after gamble selection suggest a large affective stake of the decision making and an emphasized post-decisional evaluation of the choice made by the ADHD participants. By combining ERPs, related to the emotions associated with the feedback frequency condition, and behavioral analyses during completion of PGT, this study provides new findings on the neural dynamics that differentiate controls and young ADHD adults. In the patients' group, we raise the hypothesis that the activity of frontocentral and centroparietal neural circuits drive the decision-making processes dictated by an impaired cognitive workload followed by the build-up of large emotional feelings generated by the conflict toward the outcome of the gambling choice. Our results can be used for new investigations aimed at studying the fine spatiotemporal distribution of cortical activity, and the neural circuits that underly the generation of that activity, associated with the behavioral deficits characteristic of ADHD
Role of Insulin-Like Growth Factor Receptor 2 across Muscle Homeostasis: Implications for Treating Muscular Dystrophy
The insulin-like growth factor 2 receptor (IGF2R) plays a major role in binding and regulating the circulating and tissue levels of the mitogenic peptide insulin-like growth factor 2 (IGF2). IGF2/IGF2R interaction influences cell growth, survival, and migration in normal tissue development, and the deregulation of IGF2R expression has been associated with growth-related disease and cancer. IGF2R overexpression has been implicated in heart and muscle disease progression. Recent research findings suggest novel approaches to target IGF2R action. This review highlights recent advances in the understanding of the IGF2R structure and pathways related to muscle homeostasis
Expanding drug resistance through integron acquisition by IncFI plasmids of Salmonella enterica Typhimurium.
We conducted a 30-year retrospective analysis of IncFI plasmids from Salmonella enterica serotype Typhimurium. These plasmids have been associated with the emergence of epidemic clones of multidrug-resistant Salmonella. Molecular and genetic evidence indicates that IncFI plasmids are evolving through sequential acquisition of integrons carrying different arrays of antibiotic- resistance genes
A chemotaxonomic investigation on Vitis vinifera L. 3. Characterization of Vitis biotypes via root apex proteins
Soluble proteins from root tips were used as biochemical markers to study, taxonomically and systematically, Vitis biotypes. Analyses of total proteins in the pH range 3.5-10 and of the enzymes AcP, ADH, EST, PGM and POD indicate that only in the case of proteins and AcP the staining intensity of all samples and the variation of band pattern is taxonomically informative. A comparison between seed storage proteins and root tip proteins and an automatic data acquisition system is included
The SXI telescope on board EXIST: scientific performances
The SXI telescope is one of the three instruments on board EXIST, a
multiwavelength observatory in charge of performing a global survey of the sky
in hard X-rays searching for Supermassive Black Holes. One of the primary
objectives of EXIST is also to study with unprecedented sensitivity the most
unknown high energy sources in the Universe, like high redshift GRBs, which
will be pointed promptly by the Spacecraft by autonomous trigger based on hard
X-ray localization on board. The recent addition of a soft X-ray telescope to
the EXIST payload complement, with an effective area of ~950 cm2 in the energy
band 0.2-3 keV and extended response up to 10 keV will allow to make broadband
studies from 0.1 to 600 keV. In particular, investigations of the spectra
components and states of AGNs and monitoring of variability of sources, study
of the prompt and afterglow emission of GRBs since the early phases, which will
help to constrain the emission models and finally, help the identification of
sources in the EXIST hard X-ray survey and the characterization of the
transient events detected. SXI will also perform surveys: a scanning survey
with sky coverage of about 2pi and limiting flux of 5x10^{-14}cgs plus other
serendipitous. We give an overview of the SXI scientific performance and also
describe the status of its design emphasizing how it has been derived by the
scientific requirements.Comment: 9 pages, 6 figures, to be published in Proc. of SPIE, vol 7435-11,
200
Advanced modelling of the Planck-LFI radiometers
The Low Frequency Instrument (LFI) is a radiometer array covering the 30-70
GHz spectral range on-board the ESA Planck satellite, launched on May 14th,
2009 to observe the cosmic microwave background (CMB) with unprecedented
precision. In this paper we describe the development and validation of a
software model of the LFI pseudo-correlation receivers which enables to
reproduce and predict all the main system parameters of interest as measured at
each of the 44 LFI detectors. These include system total gain, noise
temperature, band-pass response, non-linear response. The LFI Advanced RF Model
(LARFM) has been constructed by using commercial software tools and data of
each radiometer component as measured at single unit level. The LARFM has been
successfully used to reproduce the LFI behavior observed during the LFI
ground-test campaign. The model is an essential element in the database of LFI
data processing center and will be available for any detailed study of
radiometer behaviour during the survey.Comment: 21 pages, 15 figures, this paper is part of the Prelaunch status LFI
papers published on JINST:
http://www.iop.org/EJ/journal/-page=extra.proc5/jins
The DICE calibration project: design, characterization, and first results
We describe the design, operation, and first results of a photometric
calibration project, called DICE (Direct Illumination Calibration Experiment),
aiming at achieving precise instrumental calibration of optical telescopes. The
heart of DICE is an illumination device composed of 24 narrow-spectrum,
high-intensity, light-emitting diodes (LED) chosen to cover the
ultraviolet-to-near-infrared spectral range. It implements a point-like source
placed at a finite distance from the telescope entrance pupil, yielding a flat
field illumination that covers the entire field of view of the imager. The
purpose of this system is to perform a lightweight routine monitoring of the
imager passbands with a precision better than 5 per-mil on the relative
passband normalisations and about 3{\AA} on the filter cutoff positions. The
light source is calibrated on a spectrophotometric bench. As our fundamental
metrology standard, we use a photodiode calibrated at NIST. The radiant
intensity of each beam is mapped, and spectra are measured for each LED. All
measurements are conducted at temperatures ranging from 0{\deg}C to 25{\deg}C
in order to study the temperature dependence of the system. The photometric and
spectroscopic measurements are combined into a model that predicts the spectral
intensity of the source as a function of temperature. We find that the
calibration beams are stable at the level -- after taking the slight
temperature dependence of the LED emission properties into account. We show
that the spectral intensity of the source can be characterised with a precision
of 3{\AA} in wavelength. In flux, we reach an accuracy of about 0.2-0.5%
depending on how we understand the off-diagonal terms of the error budget
affecting the calibration of the NIST photodiode. With a routine 60-mn
calibration program, the apparatus is able to constrain the passbands at the
targeted precision levels.Comment: 25 pages, 27 figures, accepted for publication in A&
Nitrogen functionalized carbon nanostructures supported Pd and Au-Pd NPs as catalyst for alcohols oxidation
Two different carbon nanotubes (CNTs) PR24-PS and Baytubes were functionalized by oxidation with nitric acid and further amination with gaseous NH3. Thus Au and Au-Pd nanoparticles were prepared by PVA/NaBH4 system and anchored on the surface of pristine CNTs and N-CNTs (Nitrogen functionalized carbon nanotubes). TEM analysis revealed that the introduction of nitrogen functionalities improves the dispersion of the metal nanoparticles on the surface of the support. This phenomena leads to an improved activity of N-CNTs based catalysts with the respect of pristine CNTs when tested in the liquid phase oxidation of alcohols
Planck-LFI radiometers tuning
"This paper is part of the Prelaunch status LFI papers published on JINST:
http://www.iop.org/EJ/journal/-page=extra.proc5/jinst"
This paper describes the Planck Low Frequency Instrument tuning activities
performed through the ground test campaigns, from Unit to Satellite Levels.
Tuning is key to achieve the best possible instrument performance and tuning
parameters strongly depend on thermal and electrical conditions. For this
reason tuning has been repeated several times during ground tests and it has
been repeated in flight before starting nominal operations. The paper discusses
the tuning philosophy, the activities and the obtained results, highlighting
developments and changes occurred during test campaigns. The paper concludes
with an overview of tuning performed during the satellite cryogenic test
campaign (Summer 2008) and of the plans for the just started in-flight
calibration.Comment: This is an author-created, un-copyedited version of an article
accepted for publication in JINST. IOP Publishing Ltd is not responsible for
any errors or omissions in this version of the manuscript or any version
derived from it. The definitive publisher authenticated version is available
online at http://dx.doi.org/10.1088/1748-0221/4/12/T12013
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