Well-functioning error monitoring of the inner and outer environments is essential for adaptively altering behavior, while malfunction characterizes conditions such as obsessive–compulsive disorder ...(OCD). The underlying brain processing is manifested as Error-Related Negativity (ERN) signal elicited following error comission, and Perceived Error Related Theta Activity (PERTA) signal elicited following detection of discrepancy in the environment. Yet, while enhanced ERN was repeatedly demonstrated in OCD patients and was found to be potentiated among their unaffected first degree relatives, no comparable observations were reported with regard to PERTA. We recorded EEG activity while OCD patients, OCD patients’ siblings (Family), and healthy controls (HC) performed computerized tasks. For the examination of ERN we used the Stroop task and for the examination of PERTA we presented correct and incorrect mathematical equations. Increased ERN (0–120 ms post response) was observed in both the OCD and Family groups, but only the OCD patients’ signal significantly differed from that of HC's. Similarly, modified PERTA activity was observed in both the OCD and Family groups in the N1 peak (65–125 ms post perceived error), but only for the OCD group this activity significantly differed from that of HC. Both ERN and PERTA's N1 are fast occurring peaks, which suggests that OCD is associate with a constantly over-activated detection system that monitors the inner and outer environment and reacts promptly following detection of a mistake. Furthermore, the modified but non-significantly different activity of the Family group suggests that the pathological condition evolves in vulnerable individuals with neuronal predisposition.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Experiments at DAΦNE-Frascati and at J-PARC are scheduled to produce K−D atoms and observe their X-ray cascade down to the 1S ground state (g.s.), thereby measuring its strong-interaction width and ...shift away from a purely Coulomb state. A width Γ1S≲1 keV will ensure good resolution of the X-ray transitions feeding the 1S g.s. Here we study the expected K−D 1S g.s. width from the perspective of global fits to level shifts and widths in heavier kaonic atoms across the periodic table, using K− nuclear optical potentials constructed from K¯N chiral interaction models. Special attention is paid to the subthreshold energy at which the K¯N subsystem interacts in the K−D atom g.s. Within this approach we predict strong-interaction upward level shift of close to 700 eV and width of about 1.2 to 1.3 keV for the K−D atom 1S g.s., in fair agreement with genuinely three-body K−D atom calculations. Comparison is made with π−D atom phenomenology.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We illustrate how nuclear polarization corrections in muonic atoms can be formally connected to inelastic response functions of a nucleus. We first discuss the point-nucleon approximation and then ...include finite-nucleon-size corrections. As an example, we compare our
ab-initio
calculation of the third Zemach moment in
μ
4
He
+
to previous phenomenological results.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We have adapted the non-symmetrized hyperspherical harmonics method (NSHH) in order to treat light hypernuclei. In the past the method has been applied in the atomic and nuclear context dealing with ...identical particle systems exclusively. We have generalized and optimized the formalism in presence of two different species of particles, namely nucleons and hyperons. Preliminary benchmark results with a modern realistic 2-body nucleon-hyperon interaction are provided.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The electric dipole polarizability quantifies the low-energy behavior of the dipole strength and is related to critical observables such as the radii of the proton and neutron distributions. Its ...computation is challenging because most of the dipole strength lies in the scattering continuum. In our paper we combine integral transforms with the coupled-cluster method and compute the dipole polarizability using bound-state techniques. Furthermore, employing different interactions from chiral effective field theory, we confirm the strong correlation between the dipole polarizability and the charge radius, and study its dependence on three-nucleon forces. Finally, we find good agreement with data for the 4He, 40Ca, and 16O nuclei, and predict the dipole polarizability for the rare nucleus 22O.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
A different formulation of the effective interaction hyperspherical harmonics (EIHH) method, suitable for non-local potentials, is presented. The EIHH method for local interactions is first shortly ...reviewed to point out the problems of an extension to non-local potentials. A viable solution is proposed and, as an application, results on the ground-state properties of 4- and 6-nucleon systems are presented. One finds a substantial acceleration in the convergence rate of the hyperspherical harmonics series. Perspectives for an application to scattering cross sections, via the Lorentz transform method are discussed.
The extraction of the relative abundances of short-range correlated (SRC) nucleon pairs from inclusive electron scattering is studied using the generalized contact formalism (GCF) with several ...nuclear interaction models. GCF calculations can reproduce the observed scaling of the cross-section ratios for nuclei relative to deuterium at high xB and large Q2, a2=(σA/A)/(σd/2). In the nonrelativistic instant-form formulation, the calculation is very sensitive to the model parameters and only reproduces the data using parameters that are inconsistent with ab initio many-body calculations. Using a light-cone GCF formulation significantly decreases this sensitivity and improves the agreement with ab initio calculations. The ratio of similar mass isotopes, such as 40Ca and 48Ca, should be sensitive to the nuclear asymmetry dependence of SRCs, but is found to also be sensitive to low-energy nuclear structure. Thus the empirical association of SRC pair abundances with the measured a2 values is only accurate to about 20%. Finally, improving this will require cross-section calculations that reproduce the data while properly accounting for both nuclear structure and relativistic effects.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The Lorentz integral transform method is briefly reviewed. The issue of the inversion of the transform, and in particular its ill-posedness, is addressed. It is pointed out that the mathematical term
...ill-posed
is misleading and merely due to a historical misconception. In this connection standard regularization procedures for the solution of the integral transform problem are presented. In particular a recent one is considered in detail and critical comments on it are provided. In addition a general remark concerning the concept of the Lorentz integral transform as a method with a
controlled resolution
is made.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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