Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 4 )

2019 ( 224 )

2018 ( 366 )

2017 ( 379 )

Custom range...

Search Results: 1 - 10 of 208539 matches for " L. Vala "
All listed articles are free for downloading (OA Articles)
Page 1 /208539
Display every page Item
Exact ground states of a staggered supersymmetric model for lattice fermions
L. Huijse,N. Moran,J. Vala,K. Schoutens
Physics , 2011, DOI: 10.1103/PhysRevB.84.115124
Abstract: We study a supersymmetric model for strongly interacting lattice fermions in the presence of a staggering parameter. The staggering is introduced as a tunable parameter in the manifestly supersymmetric Hamiltonian. We obtain analytic expressions for the ground states in the limit of small and large staggering for the model on the class of doubly decorated lattices. On this type of lattice there are two ground states, each with a different density. In one limit we find these ground states to be a simple Wigner crystal and a valence bond solid (VBS) state. In the other limit we find two types of quantum liquids. As a special case, we investigate the quantum liquid state on the one dimensional chain in detail. It is characterized by a massless kink that separates two types of order.
Supersymmetric lattice fermions on the triangular lattice: superfrustration and criticality
L. Huijse,D. Mehta,N. Moran,K. Schoutens,J. Vala
Physics , 2011, DOI: 10.1088/1367-2630/14/7/073002
Abstract: We study a model for itinerant, strongly interacting fermions where a judicious tuning of the interactions leads to a supersymmetric Hamiltonian. On the triangular lattice this model is known to exhibit a property called superfrustration, which is characterized by an extensive ground state entropy. Using a combination of numerical and analytical methods we study various ladder geometries obtained by imposing doubly periodic boundary conditions on the triangular lattice. We compare our results to various bounds on the ground state degeneracy obtained in the literature. For all systems we find that the number of ground states grows exponentially with system size. For two of the models that we study we obtain the exact number of ground states by solving the cohomology problem. For one of these, we find that via a sequence of mappings the entire spectrum can be understood. It exhibits a gapped phase at 1/4 filling and a gapless phase at 1/6 filling and phase separation at intermediate fillings. The gapless phase separates into an exponential number of sectors, where the continuum limit of each sector is described by a superconformal field theory.
Is Siege Mentality a Hegemonic Belief in Israel? A Comment on Bar-Tal and Antebi
Vala, Jorge
Papers on Social Representations , 1992,
Testing of the point accuracy of measurements by the RTK method at different distances of the reference station for monitoring of the dynamic effect in a subsidence basin
Roman Vala
Acta Montanistica Slovaca , 2007,
Abstract: In the area of Technical University in Ostrava were stabilized 35 points for testing of the accuracy of RTK measurement. All points of the testing base line were located by a new digital leveling instrument Leica DNA 03 with a precise leveling line. The position of all the points was determined by classical methods (polygonal traverse) as well. Each point was focused three times by the RTK method in relation to the same reference station. The point coordinates were located against the reference station, which was gradually placed in the attached points. The results of given point coordinates were compared mutually and with coordinates acquired by a classical method.
Jorge Vala
Análise Social , 2011,
Results of NEMO 3 and status of SuperNEMO
Ladislav Vala
Physics , 2009, DOI: 10.1016/j.nuclphysbps.2009.02.015
Abstract: The NEMO 3 experiment is devoted to the search for neutrinoless double beta decay, as well as for accurate measurement of two-neutrino double beta decay. The detector has been taking data in the LSM laboratory since 2003 and the latest NEMO 3 results for seven double beta decay isotopes are presented here for both decay modes. The SuperNEMO project aims to extend the NEMO technique to a 100-200 kg isotope experiment with the target half-life sensitivity of 1-2 x 10^26 y. The current status of the SuperNEMO R&D programme is described.
Cren?a no mundo justo e vitimiza??o secundária: o papel moderador da inocência da vítima e da persistência do sofrimento
Correia,Isabel; Vala,Jorge;
Análise Psicológica , 2003,
Abstract: the goal of the studies presented in this article is to test the basic prediction of the belief in a just world (bjw) theory according to which observers that are high believers in a jw victimize more an innocent victim whose suffering persists than observers that are low believers in a jw. in fact, this theory predicts that three factors determine the reaction of an observer towards a victim: the observers' bjw, the innocence of the victim and the persistence of the victim's suffering. however to date no study tried to determine the joint impact of these three factors. the studies presented in this article analyse the joint impact of these three factors on secondary victimization. the results show that participants who most need to re-establish their bjw, either because it is high (study 1 and 2) or because it has been threatened (study 3), victimize the victim more: they regard the victim as being more deserving of the situation in which he/she finds himself/herself (study 1), in a fairer situation than observers with a lower level of bjw (study 2), and they devalue the victim more (study 3).
Cytotoxic Impacts of Linear and Branched Polyethylenimine Nanostructures in A431 Cells
Vala Kafil,Yadollah Omidi
BioImpacts , 2011,
Abstract: Introduction: Polyethylenimine (PEI), as a nonviral cationic polymer, has been widely used as gene delivery nanosystem. Although a number of investigations have highlighted its toxic impacts on target cells through induction of apoptosis/necrosis, still it is essential to look at its structural impacts on target cells. Methods: In this current study, cytogenomic impacts of 25 kD linear and branched PEI (LPEI and BPEI, respectively) in A431 cells are reported to address possible mechanism for induction of apoptosis. At 40-50% confluency, A431 cells were exposed to PEI at a recommended concentration for 4 hr. After 24 hr, to detect apoptosis and DNA damage, the treated cells were subjected to MTT assay, FITC-labeled annexin V flow cytometry and comet assay. Results: Flow cytometry assessments revealed that the BPEI can result in greater internalization than the linear PEI, which also induced greater cytotoxicity. Annexin V assay confirmed early and late apoptosis by BPEI, imposing somewhat DNA damage detected by comet assay. Western blot analysis resulted in induction of Akt-kinase which is possibly one of biomolecules affected by PEI. Conclusion: These results highlight that, despite induction of Akt-kinase, the BPEI can elicit apoptosis in target cells.
Results from the NEMO 3 experiment
Ladislav Vala,for the NEMO Collaboration
Physics , 2007, DOI: 10.1016/j.nuclphysbps.2007.02.008
Abstract: The aim of the NEMO 3 experiment is the search for neutrinoless double beta decay and precise measurement of two-neutrino double beta decay of several isotopes. The experiment has been taking data since 2003. Since no evidence for neutrinoless double beta decay of Mo100 and Se82 has been found, a 90% C.L. lower limit on the half-life of this process and corresponding upper limit on the effective Majorana neutrino mass are derived. The data are also interpreted in terms of alternative models, such as weak right-handed currents or Majoron emission. In addition, NEMO 3 has performed precision measurements of the two-neutrino double beta decay for seven different isotopes. The most recent experimental results of NEMO 3 are presented in this paper.
Zero energy and chiral edge modes in a p-wave magnetic spin model
G. Kells,J. Vala
Physics , 2010, DOI: 10.1103/PhysRevB.82.125122
Abstract: In this work we discuss the formation of zero energy vortex and chiral edge modes in a fermionic representation of the Kitaev honeycomb model. We introduce the representation and show how the associated Jordan-Wigner procedure naturally defines the so called branch cuts that connect the topological vortex excitations. Using this notion of the branch cuts we show how to, in the non-Abelian phase of the model, describe the Majorana zero mode structure associated with vortex excitations. Furthermore we show how, by intersecting the edges between Abelian and non-Abelian domains, the branch cuts dictate the character of the chiral edge modes. In particular we will see in what situations the exact zero energy Majorana edge modes exist. On a cylinder, and for the particular instances where the Abelian phase of the model is the full vacuum, we have been able to exactly solve for the systems edge energy eigensolutions and derive a recursive formula that exactly describes the edge mode structure. Penetration depth is also calculated and shown to be dependent on the momentum of the edge mode. These solutions also describe the overall character of the fully open non-Abelian domain and are excellent approximations at moderate distances from the corners.
Page 1 /208539
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.