14,604 research outputs found
Pathological video game playing in Spanish and British adolescents: towards the exploration of Internet Gaming Disorder symptomatology
Research into problematic video gaming has increased greatly over the last decade and many screening instruments have been developed to identify such behaviour. This study re-examined the Problematic Videogame Playing [PVP] Scale. The objectives of the study were to (i) examine its psychometric properties in two European countries, (ii) estimate the prevalence of potential pathological gaming among adolescents in both countries, and (iii) assess the classification accuracy of the PVP Scale based on its symptomatology as a way of exploring its relationship with both the behavioural component model of addiction and the proposed Internet Gaming Disorder. The data were collected via a survey administered to 2,356 adolescents aged between 11 and 18 years from Spain (n=1,132) and Great Britain (n=1,224). Results indicated that the reliability of both versions was adequate, and the factorial and construct validity were good. Findings also showed that the prevalence of pathological gamers estimated with a rigorous cut-off point was 7.7% for Spanish and 14.6% for British adolescents. The scale showed adequate sensitivity, specificity and classification accuracy in both countries, and was able to differentiate between social and potential pathological gamers, and from their addictive symptomatology. The implications of these findings are discussed
Mapping of the Tacaribe Arenavirus Z-Protein Binding Sites on the L Protein Identified both Amino Acids within the Putative Polymerase Domain and a Region at the N Terminus of L That Are Critically Involved in Binding
Tacaribe virus (TacV) is the prototype of the New World group of arenaviruses. The TacV genome encodes four proteins: the nucleoprotein (N), the glycoprotein precursor, the polymerase (L), and a RING finger protein (Z). Using a reverse genetics system, we demonstrated that TacV N and L are sufficient to drive transcription and replication mediated by TacV-like RNAs and that Z is a powerful inhibitor of these processes (Lopez et al., J. Virol. 65:12241-12251, 2001). More recently, we provided the first evidence of an interaction between Z and L and showed that Z's inhibitory activity was dependent on its ability to bind to L (JĂĄcamo et al., J. Virol. 77:10383-10393, 2003). In the present study, we mapped the TacV Z-binding sites on the 2,210-amino-acid L polymerase. To that end, we performed deletion analysis and point mutations of L and studied the Z-L interaction by coimmunoprecipitation with specific sera. We found that the C-terminal region of L was not essential for the interaction and identified two noncontiguous regions that were critical for binding: one at the N-terminus of L between residues 156 and 292 and a second one in the polymerase domain (domain III). The importance of domain III in binding was revealed by substitutions in D1188 and H1189 within motif A and in each residue of the conserved SDD sequence (residues 1328, 1329, and 1330) within motif C. Our results showed that of the substituted residues, only H1189 and D1329 appeared to be critically involved in binding Z.Fil: Wilda, Maximiliano. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de MicrobiologĂa, InmunologĂa y BiotecnologĂa. CĂĄtedra de GenĂ©tica y BiologĂa Molecular; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Lopez, Nora Mabel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Instituto de Ciencia y TecnologĂa "Dr. CĂ©sar Milstein"; ArgentinaFil: Casabona, Juan Cruz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Instituto de Ciencia y TecnologĂa "Dr. CĂ©sar Milstein"; ArgentinaFil: Franze Fernandez, Maria T.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de MicrobiologĂa, InmunologĂa y BiotecnologĂa. CĂĄtedra de GenĂ©tica y BiologĂa Molecular; Argentin
Kinematics of the Outflow From The Young Star DG Tau B: Rotation in the vicinities of an optical jet
We present CO(2-1) line and 1300 m continuum observations made
with the Submillimeter Array (SMA) of the young star DG Tau B. We find, in the
continuum observations, emission arising from the circumstellar disk
surrounding DG Tau B. The CO(2-1) line observations, on the other hand,
revealed emission associated with the disk and the asymmetric outflow related
with this source. Velocity asymmetries about the flow axis are found over the
entire length of the flow. The amplitude of the velocity differences is of the
order of 1 -- 2 km s over distances of about 300 -- 400 AU. We interpret
them as a result of outflow rotation. The sense of the outflow and disk
rotation is the same. Infalling gas from a rotating molecular core cannot
explain the observed velocity gradient within the flow. Magneto-centrifugal
disk winds or photoevaporated disk winds can produce the observed rotational
speeds if they are ejected from a keplerian disk at radii of several tens of
AU. Nevertheless, these slow winds ejected from large radii are not very
massive, and cannot account for the observed linear momentum and angular
momentum rates of the molecular flow. Thus, the observed flow is probably
entrained material from the parent cloud. DG Tau B is a good laboratory to
model in detail the entrainment process and see if it can account for the
observed angular momentum.Comment: Accepted to Ap
Functional near-infrared spectroscopy in the neuropsychological assessment of spatial memory: A systematic review; 35123299
Functional near-infrared spectroscopy (fNIRS) is a non-invasive optical imaging technique that employs near-infrared light to measure cortical brain oxygenation. The use of fNIRS has increased exponentially in recent years. Spatial memory is defined as the ability to learn and use spatial information. This neuropsychological process is constantly used in our daily lives and can be measured by fNIRS but no research has reviewed whether this technique can be useful in the neuropsychological assessment of spatial memory. This study aimed to review empirical work on the use of fNIRS in the neuropsychological assessment of human spatial memory. We used four databases: PubMed, PsycINFO, Scopus and Web of Science, and a total of 18 articles were found to be eligible. Most of the articles assessed spatial or visuospatial working memory with a predominance in computer-based tasks, used fNIRS equipment of 16 channels and mainly measured the prefrontal cortex (PFC). The studies analysed found linear or quadratic relationships between working memory load and PFC activity, greater activation of PFC activity and worse behavioural results in healthy older people in comparison with healthy adults, and hyperactivation of PFC as a form of compensation in clinical samples. We conclude that fNIRS is compatible with the standard neuropsychological assessment of spatial memory, making it possible to complement behavioural results with data of cortical functional activity. © 202
EURONU WP6 2009 yearly report: Update of the physics potential of Nufact, superbeams and betabeams
Many studies in the last ten years have shown that we can measure the unknown
angle theta13, discover leptonic CP violation and determine the neutrino
hierarchy in more precise neutrino oscillation experiments, searching for the
subleading channel nue -> numu in the atmospheric range. In this first report
of WP6 activities the following new results are reviewed: (1) Re-evaluation of
the physics reach of the upcoming generation of experiments to measure theta13
and delta; (2) New tools to explore a larger parameter space as needed beyond
the standard scenario; (3) Neutrino Factory: (a) evaluation of the physics
reach of a Nufact regards sterile neutrinos; (b) evaluation of the physics
reach of a Nufact as regards non-standard interactions; (c) evaluation of the
physics reach of a Nufact as regards violation of unitarity; (d) critical
assessment on long baseline tau-detection at Nufact; (e) new physics searches
at a near detector in a Nufact; (4) Beta-beams: (a) choice of ions and location
for a gamma = 100 CERN-based beta-beam; (b) re-evaluation of atmospheric
neutrino background for the gamma = 100 beta-beam scenario; (c) study of a two
baseline beta-beam; (d) measuring absolute neutrino mass with beta-beams; (e)
progress on monochromatic beta-beams; (5) Update of the physics potential of
the SPL super-beam. Eventually, we present an updated comparison of the
sensitivity to theta13, delta and the neutrino mass hierarchy of several of the
different proposed facilities.Comment: 2009 Yearly report of the Working Package 6 (Physics) of the EUROnu
FP7 EU project. 55 pages, 21 figures
On the MBM12 Young Association
I present a comprehensive study of the MBM12 young association (MBM12A). By
combining infrared (IR) photometry from the Two-Micron All-Sky Survey (2MASS)
survey with new optical imaging and spectroscopy, I have performed a census of
the MBM12A membership that is complete to 0.03 Msun (H~15) for a 1.75deg X
1.4deg field encompassing the MBM12 cloud. I find five new members with masses
of 0.1-0.4 Msun and a few additional candidates that have not been observed
spectroscopically. From an analysis of optical and IR photometry for stars in
the direction of MBM12, I identify M dwarfs in the foreground and background of
the cloud. By comparing the magnitudes of these stars to those of local field
dwarfs, I arrive at a distance modulus 7.2+/-0.5 (275 pc) to the MBM12 cloud;
it is not the nearest molecular cloud and is not inside the local bubble of hot
ionized gas as had been implied by previous distance estimates of 50-100 pc. I
have also used Li strengths and H-R diagrams to constrain the absolute and
relative ages of MBM12A and other young populations; these data indicate ages
of 2 +3/-1 Myr for MBM12A and 10 Myr for the TW Hya and Eta Cha associations.
MBM12A may be a slightly evolved version of the aggregates of young stars
within the Taurus dark clouds (~1 Myr) near the age of the IC 348 cluster (~2
Myr).Comment: to be published in The Astrophysical Journal, 41 pages, 14 figures,
also found at http://cfa-www.harvard.edu/sfgroup/preprints.htm
Monitoring the influence of marine aquaculture on wild fish communities: benefits and limitations of fatty acid profiles
Fatty acids (FA) have been applied as indicators of the influence of coastal sea-cage fish farming on wild fish communities in several recent scientific publications. Due to the relatively high conservation of FA composition throughout the food web, they are useful for characterizing trophic relationships. The increasing utilization of vegetable or alternative animal oils in the production of aquafeeds results in cultivated fish exhibiting higher levels of terrestrial FAs in their tissues. As previously reported, wild fish ubiquitously aggregate around fish farms as a consequence of the introduction of new habitat and the easy availability of foodâfish farms act as enhanced fish aggregation devices (FADs). The influence of food pellets on the composition of wild fish has been detected in recent studies on salmon, sea bass and sea bream aquaculture, with increased levels of linoleic acid (18:2n-6) and a low n-3/n-6 ratio as clear indicators of the consumption of food pellets from the farms. The potential ecological and physiological effects on wild fish are presently unknown. In the present article, guidelines are proposed for the investigation and use of terrestrial FAs to track the effects of coastal aquaculture on wild fish communities and local fisheries, as well as the benefits or limitations of this technique
Leukocyte extract reduces HIV replication and modulates cellular factors involved in HIV infection: therapeutic meant
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