383 research outputs found
Déjà vu and the entorhinal cortex: dissociating recollective from familiarity disruptions in a single case patient
Past research has demonstrated a relationship between déjà vu and the entorhinal cortex in patients with wider medial temporal lobe damage. The aim of the present research was to investigate this crucial link in a patient (MR) with a selective lesion to the left lateral entorhinal cortex to provide a more direct exploration of this relationship. Two experiments investigated the experiences of déjà vécu (using the IDEA questionnaire) and déjà vu (using an adapted DRM paradigm) in MR and a set of matched controls. The results demonstrated that MR had quantitatively more and qualitatively richer recollective experiences of déjà vécu. In addition, under laboratory-based déjà vu conditions designed to elicit both false recollection (critical lures) and false familiarity (weakly-associated lures), MR only revealed greater memory impairments for the latter. The present results are therefore the first to demonstrate a direct relationship between the entorhinal cortex and the experience of both déjà vu and déjà vécu. They furthermore suggest that the entorhinal cortex is involved in both weakly-associative false memory as well as strongly-associative memory under conditions that promote familiarity-based processing
Alpha-cluster Condensations in Nuclei and Experimental Approaches for their Studies
The formation of alpha-clusters in nuclei close to the decay thresholds is
discussed. These states can be considered to be boson-condensates, which are
formed in a second order phase transition in a mixture of nucleons and
alpha-particles. The de Broglie wavelength of the alpha-particles is larger
than the nuclear diameter, therefore the coherent properties of the
alpha-particles give particular effects for the study of such states. The
states are above the thresholds thus the enhanced emission of multiple-alphas
into the same direction is observed. The probability for the emission of
multiple-alphas is not described by Hauser-Feshbach theory for compound nucleus
decay.Comment: 21 pages, 12 figures
Rotating hyperdeformed quasi-molecular states formed in capture of light nuclei and in collision of very heavy ions
International audienceWithin a rotational liquid drop model including the nuclear proximity energy the l-dependent potential barriers governing the capture reactions of light nuclei and of very heavy ions have been determined. Rotating quasi-molecular hyperdeformed states appear at high angular momenta. The energy range of these very deformed high spin states is given for light systems. The same approach explains the observation of ternary cluster decay from56Ni and 60Zn through hyperdeformed shapes at angular momenta around 45 . The apparently observed superheavy nuclear systems in the U+Ni and U+Ge reactions at high excitation energy might correspond to these rotating isomeric states formed at very high angular momenta even though the shell effects vanish
From the stable to the exotic: clustering in light nuclei
A great deal of research work has been undertaken in alpha-clustering study
since the pioneering discovery of 12C+12C molecular resonances half a century
ago. Our knowledge on physics of nuclear molecules has increased considerably
and nuclear clustering remains one of the most fruitful domains of nuclear
physics, facing some of the greatest challenges and opportunities in the years
ahead. The occurrence of "exotic" shapes in light N=Z alpha-like nuclei is
investigated. Various approaches of the superdeformed and hyperdeformed bands
associated with quasimolecular resonant structures are presented. Evolution of
clustering from stability to the drip-lines is examined: clustering aspects
are, in particular, discussed for light exotic nuclei with large neutron excess
such as neutron-rich Oxygen isotopes with their complete spectroscopy.Comment: 15 pages, 5 figures, Presented at the International Symposium on "New
Horizons in Fundamental Physics - From Neutrons Nuclei via Superheavy
Elements and Supercritical Fields to Neutron Stars and Cosmic Rays" held at
Makutsi Safari Farm, South Africa, December 23-29, 2015. arXiv admin note:
substantial text overlap with arXiv:1402.6590, arXiv:1303.0960,
arXiv:1408.0684, arXiv:1011.342
4He decay of excited states in 14C
A study of the 7Li(9Be,4He 10Be)2H reaction at E{beam}=70 MeV has been
performed using resonant particle spectroscopy techniques and provides the
first measurements of alpha-decaying states in 14C. Excited states are observed
at 14.7, 15.5, 16.4, 18.5, 19.8, 20.6, 21.4, 22.4 and 24.0 MeV. The
experimental technique was able to resolve decays to the various particle bound
states in 10Be, and provides evidence for the preferential decay of the high
energy excited states into states in 10Be at ~6 MeV. The decay processes are
used to indicate the possible cluster structure of the 14C excited states.Comment: accepted for publication in PR
Indications for a Detonating Quark-Gluon Plasma
We propose a mechanism which naturally contains the relation of the hadronic gas produced in heavy-ion collisions at CERN. Our
starting assumption is the existence of a sharp front separating the
quark-gluon plasma phase from the hadronic phase. Energy-momentum conservation
across the front leads to the following consequences for an adiabatic process
a) The baryon chemical potential, , is approximately continuous across
the front. b) The temperature in the hadronic gas is higher than the phase
transition temperature due to superheating. c) In the region covered by the
experiments the velocity of the hadronic gas approximately equals the speed of
sound in the hadronic gas.Comment: Latex file 9 pages + 6 figures available as postscript file
Linear chain structure of four- clusters in O
We investigate the linear-chain configurations of four- clusters in
O using a Skyrme cranked Hartree-Fock method and discuss the
relationship between the stability of such states and angular momentum. We show
the existence of a region of angular momentum (13-18 ) where the linear
chain configuration is stabilized. For the first time we demonstrate that
stable exotic states with a large moment of inertia (
0.06-0.08 MeV) can exist.Comment: 4 pages, 6 figur
Deformed two center shell model
A highly specialized two-center shell model has been developed accounting for
the splitting of a deformed parent nucleus into two ellipsoidaly deformed
fragments. The potential is based on deformed oscillator wells in direct
correspondance with the shape change of the nuclear system. For the first time
a potential responsible for the necking part between the fragments is
introduced on potential theory basis. As a direct consequence, spin-orbit {\bf
ls} and {\bf l} operators are calculated as shape dependent. Level scheme
evolution along the fission path for pairs of ellipsoidaly deformed fragments
is calculated. The Strutinsky method yields the shell corrections for different
mass asymmetries from the superheavy nucleus 122 and Cf all
along the splitting process.Comment: 32 pages, 8 figure
Expert opinion on diagnosis and management of epilepsy-associated comorbidities
Apart from seizure freedom, the presence of comorbidities related to neurological, cardiovascular, or psychiatric disorders is the largest determinant of a reduced health-related quality of life in people with epilepsy (PwE). However, comorbidities are often underrecognized and undertreated, and clinical management of comorbid conditions can be challenging. The focus of a comprehensive treatment regimen should maximize seizure control while optimizing clinical management of treatable comorbidities to improve a person's quality of life and overall health. A panel of four European epileptologists with expertise in their respective fields of epilepsy-related comorbidities combined the latest available scientific evidence with clinical expertise and collaborated to provide consensus practical advice to improve the identification and management of comorbidities in PwE. This review provides a critical evaluation for the diagnosis and management of sleep–wake disorders, cardiovascular diseases, cognitive dysfunction, and depression in PwE. Whenever possible, clinical data have been provided. The PubMed database was the main search source for the literature review. The deleterious pathophysiological processes underlying neurological, cardiovascular, or psychiatric comorbidities in PwE interact with the processes responsible for generating seizures to increase cerebral and physiological dysfunction. This can increase the likelihood of developing drug-resistant epilepsy; therefore, early identification of comorbidities and intervention is imperative. The practical evidence-based advice presented in this article may help clinical neurologists and other specialist physicians responsible for the care and management of PwE.Peer reviewe
Entropically-driven binding of mithramycin in the minor groove of C/G-rich DNA sequences
Final full-text version available at: http://dx.doi.org/10.1093/nar/gkm037.-- Supplementary Data is available.The antitumour antibiotic mithramycin A (MTA) is a DNA minor-groove binding ligand. It binds to C/G-rich tracts as a dimer that forms in the presence of divalent cations such as Mg2+. Differential scanning calorimetry, UV thermal denaturation, isothermal titration calorimetry and competition dialysis were used, together with computations of the hydrophobic free energy of binding, to determine the thermodynamic profile of MTA binding to DNA. The results were compared to those obtained in parallel using the structurally related mithramycin SK (MSK). The binding of MTA to salmon testes DNA determined by UV melting studies (Kobs = 1.2 (±0.3) x 10^5 M–1) is tighter than that of MSK (2.9 (±1.0) x 10^4 M–1) at 25°C. Competition dialysis studies showed a tighter MTA binding to both salmon testes DNA (42% C + G) and Micrococcus lysodeikticus DNA (72% C + G). The thermodynamic analysis of binding data at 25°C shows that the binding of MTA and MSK to DNA is entropically driven, dominated by the hydrophobic transfer of the antibiotics from solution to the DNA-binding site. Direct molecular recognition between MTA or MSK and DNA through hydrogen bonding and van der Waals contacts may also contribute significantly to complex formation.Supported by a grant from the Spanish Ministry of Education and Science (SAF2005-00551) and the FEDER program of the European Community. This work was carried out within the framework of the Centre de Referencia en Biotecnologia of the Generalitat de Catalunya. Funding to pay the Open Access publication charge was provided by the Ministry of Education and Science and CSIC (Spain).Peer reviewe
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