63 research outputs found
Dynamics of a many-particle Landau-Zener model: inverse sweep
We consider dynamics of a slowly time-dependent Dicke model, which represents
a many-body generalization of the Landau-Zener model. In particular, the model
describes narrow Feshbach resonance passage in an ultracold gas of Fermi atoms.
Adiabaticity is destroyed when a parameter crosses a critical value, even at
very slow sweeping rates of a parameter. The dynamics crucially depends on
direction of the sweep. We apply our recent analysis [A.P. Itin, P. Torma,
arXiv:0901.4778v1] to the "inverse" sweep through the resonance, corresponding
(in a context of Feshbach resonance passage) to dissociation of molecules. On a
level of the mean-field approximation, the dynamics is equivalent to a
molecular condensate formation from Bose atoms within a two-mode model. Mapping
the system to a Painlev\'e equation allows us to calculate deviation from
adiabaticity at very slow sweeps analytically.Comment: 3 pages. Submitted to CEWQO 2009 on 14th Februar
Non-adiabacity and large flucutations in a many particle Landau Zener problem
We consider the behavior of an interacting many particle system under slow
external driving -- a many body generalization of the Landau-Zener paradigm. We
find that a conspiracy of interactions and driving leads to physics profoundly
different from that of the single particle limit: for practically all values of
the driving rate the particle distributions in Hilbert space are very broad, a
phenomenon caused by a strong amplification of quantum fluctuations in the
driving process. These fluctuations are 'non-adiabatic' in that even at very
slow driving it is exceedingly difficult to push the center of the distribution
towards the limit of full ground state occupancy. We obtain these results by a
number of complementary theoretical approaches, including diagrammatic
perturbation theory, semiclassical analysis, and exact diagonalization.Comment: 25 pages, 16 figure
METHODOLOGICAL APPROACHES TO THE ESTIMATION OF INDIVIDUAL OCCUPATIONAL RISK TAKING INTO ACCOUNT INDICATORS OF LIFE QUALITY
Authors offer to make changes to technique of the estimation of life quality with three blocks of professional and nonprofessional risk factors: index of observance of requirements of sanitary legislations; index of way of life and index of social well-being. The index of observance of requirements of sanitary legislations pays off by result of an expert estimation of a workplace taking into account aggravating (absence of certification of workplaces, industrial inspection; insufficiency of the area and volume of premises; absence of ventilation, repairs, work and rest modes; neediness of good-quality potable water, sanitary-household premises, first-aid sets of the first medical aid; absence of system of informing of workers about an existing professional risk and ways of its decrease etc.) and normalizing factors (presence of complexes intrareplaceable and after a labor shift medical rehabilitations etc.). The index of way of life is offered to be counted taking into account major individual behavioral and biological factors of risk of death rate and invalidity in Russia: smoking, abusing alcohol, irrational food (in particular, the uses less than 400 g vegetables and fruit in day), insufficient physical activity, raised index of weight of a body, psychoemotional stress, raised levels of cholesterol and glucose in whey of blood, arterial pressure, burdened heredity. The index of social well-being pays off as the one-numerical indicator considering social and economic and socially-psychological factors: indicator of size of wages, indicator of satisfaction health, working conditions, work as a whole, life as a whole, an indicator of the individual importance of factors of psychological overload. Authors of article suggest to add an existing technique of an estimation of an indicator of the individual importance of psychological overload factors with indicators actual in modern industrial conditions: socially-psychological adaptation, degree of emotional burning out, quality of life. The estimation of quality of life can serve in this system to one of the most significant after experience medical and biologic criteria of an estimation of an individual professional risk
Fungal vaccines and immunotherapeutics: current concepts and future challenges
Purpose of review The remarkable advances in modern medicine have paradoxically resulted in a rapidly expanding population of immunocompromised patients displaying extreme susceptibility to life-threatening fungal infections. There are currently no licensed vaccines, and the prophylaxis and therapy of fungal infections in at-risk individuals remains challenging, contributing to undesirable mortality and morbidity rates. The design of successful antifungal preventive approaches has been hampered by an insufficient understanding of the dynamics of the host-fungus interaction and the mechanisms that underlie heterogenous immune responses to vaccines and immunotherapy. Recent findings Recent advances in proteomics and glycomics have contributed to the identification of candidate antigens for use in subunit vaccines, novel adjuvants, and delivery systems to boost the efficacy of protective vaccination responses that are becoming available, and several targets are being exploited in immunotherapeutic approaches. Summary We review some of the emerging concepts as well as the inherent challenges to the development of fungal vaccines and immunotherapies to protect at-risk individuals.ThisworkwassupportedbytheNorthernPortugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) (NORTE-01-0145-FEDER-000013), and the Fundação para a Ciência e Tecnologia (FCT) (contracts IF/00735/ 2014 to A.C., and SFRH/BPD/96176/2013 to C.C).info:eu-repo/semantics/publishedVersio
Quantum-mechanical and semiclassical study of the collinear three-body Coulomb problem: Inelastic collisions below the three-body disintegration threshold
Relativistic pseudo-Jahn-Teller effect in the square-planar molecules with a central atom
Surface Termination Control in Chemically Deposited PbS Films: Nucleation and Growth on GaAs(111)A and GaAs(111)B
Method of Momentum Representation in the Relativistic Jan–Teller Effect G g [3/2] × (t2g + e g )
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