131 research outputs found

    Linearization of Cohomology-free Vector Fields

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    We study the cohomological equation for a smooth vector field on a compact manifold. We show that if the vector field is cohomology free, then it can be embedded continuously in a linear flow on an Abelian group

    Theoretical prediction of spectral and optical properties of bacteriochlorophylls in thermally disordered LH2 antenna complexes

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    A general approach for calculating spectral and optical properties of pigment-protein complexes of known atomic structure is presented. The method, that combines molecular dynamics simulations, quantum chemistry calculations and statistical mechanical modeling, is demonstrated by calculating the absorption and circular dichroism spectra of the B800-B850 BChls of the LH2 antenna complex from Rs. molischianum at room temperature. The calculated spectra are found to be in good agreement with the available experimental results. The calculations reveal that the broadening of the B800 band is mainly caused by the interactions with the polar protein environment, while the broadening of the B850 band is due to the excitonic interactions. Since it contains no fitting parameters, in principle, the proposed method can be used to predict optical spectra of arbitrary pigment-protein complexes of known structure.Comment: ReVTeX4, 11 pages, 9 figures, submitted to J. Chem. Phy

    PSYCHIATRY AND MOVIES

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    As one of the most potent and substantial form of mass communication, film exercises a very significant influence upon the perceptions of the audience, especially in relation to mental illness issues, and that perception is very much blurred with populists’ misinterpretation and lack of awareness regarding problems faced by persons suffering from mental disorders. Movies such as “Psycho”, “One Flew Over Cuckoo’s Nest”, “Exorcist”, despite being valuable in an artistic sense, corroborated and encouraged confusion and undermined the clarity and certainty concerning the fine line separating mental health from mental illness. Modern film makers and movie theoreticians try to overcome these limitations which are often generated by exploitation of stereotypes and myths referring to mentally ill people. This paper defines and discusses the most frequent thematic stereotypes seen in movies which are perpetuating stigmatization of mentally ill people. They are: freespirited rebel, maniac on a killing spree, seducer, enlightened member of society, narcissistic parasite, beastly person (stereotype of animal sort). Psychiatry and cinematography are linked inseparably not only because they creatively complement each other, but also as an opportunity of mutual influences blending into didactical categories and professional driving forces, benefiting both the filmmakers’ and the psychiatrists’ professions

    Predicting violence in veterans with posttraumatic stress disorder

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    Background/Aim. Frequent expression of negative affects, hostility and violent behavior in individuals suffering from posttraumatic stress disorder (PTSD) were recognized long ago, and have been retrospectively well documented in war veterans with PTSD who were shown to have an elevated risk for violent behavior when compared to both veterans without PTSD and other psychiatric patients. The aim of this study was to evaluate the accuracy of clinical prediction of violence in combat veterans suffering from PTSD. Methods. The subjects of this study, 104 male combat veterans with PTSD were assessed with the Historical, Clinical and Risk Management 20 (HCR-20), a 20-item clinicianrated instrument for assessing the risks for violence, and their acts of violence during one-year follow-up period were registered based on bimonthly check-up interviews. Results. Our findings showed that the HCR-20, as an actuarial measure, had good internal consistency reliability (α = 0.82), excellent interrater reliability (Interaclass Correlation ICC = 0.85), as well as excellent predictive validity for acts of any violence, non-physical violence or physical violence in the follow-up period (AUC = 0.82-0.86). The HCR-20 also had good interrater reliability (Cohen's kappa = 0.74), and acceptable predictive accuracy for each outcome criterion (AUC = 0.73-0.79). Conclusion. The results of this research confirm that the HCR-20 may also be applied in prediction of violent behavior in the population of patients suffering from PTSD with reliability and validity comparable with the results of previous studies where this instrument was administered to other populations of psychiatric patients

    THE HISTORICAL DEVELOPMENT OF PSYCHIATRY IN SERBIA

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    The authors present the development of the concept of mental disease and treatment in Serbian medicine. Serbian medieval medicine did not acknowledge fortune telling, sorcery, the use of amulets and magical rituals and formulas. These progressive concepts were confirmed by the Church and the Serbian state in what is known as Dušan’s Code. The Historical data on the establishment of the first psychiatric hospital in the Balkans “Home for the Unsound of Mind” at Guberevac, Belgrade, in 1861 and its founders is reviewed. After World War I, in 1923, the Faculty of Medicine was established in Belgrade to which the coryphaei of Serbian medicine educated in Europe, mostly in France and Germany, flocked and that same year the Psychiatry Clinic of the Faculty of Medicine in Belgrade was set up. Its first seat was on the premises of the Mental Hospital in Belgrade, and it became a training base and laid the foundations of the future Neuropsychiatry Clinic in Belgrade, which in time evolved into the nursery of psychiatric professionals for all of Serbia. The most important data on the further development of psychiatry up to date are presented

    Excitons in a Photosynthetic Light-Harvesting System: A Combined Molecular Dynamics/Quantum Chemistry and Polaron Model Study

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    The dynamics of pigment-pigment and pigment-protein interactions in light-harvesting complexes is studied with a novel approach which combines molecular dynamics (MD) simulations with quantum chemistry (QC) calculations. The MD simulations of an LH-II complex, solvated and embedded in a lipid bilayer at physiological conditions (with total system size of 87,055 atoms) revealed a pathway of a water molecule into the B800 binding site, as well as increased dimerization within the B850 BChl ring, as compared to the dimerization found for the crystal structure. The fluctuations of pigment (B850 BChl) excitation energies, as a function of time, were determined via ab initio QC calculations based on the geometries that emerged from the MD simulations. From the results of these calculations we constructed a time-dependent Hamiltonian of the B850 exciton system from which we determined the linear absorption spectrum. Finally, a polaron model is introduced to describe quantum mechanically both the excitonic and vibrational (phonon) degrees of freedom. The exciton-phonon coupling that enters into the polaron model, and the corresponding phonon spectral function are derived from the MD/QC simulations. It is demonstrated that, in the framework of the polaron model, the absorption spectrum of the B850 excitons can be calculated from the autocorrelation function of the excitation energies of individual BChls, which is readily available from the combined MD/QC simulations. The obtained result is in good agreement with the experimentally measured absorption spectrum.Comment: REVTeX3.1, 23 pages, 13 (EPS) figures included. A high quality PDF file of the paper is available at http://www.ks.uiuc.edu/Publications/Papers/PDF/DAMJ2001/DAMJ2001.pd

    A SUGGESTION FOR PROACTIVE CARDIOLOGIC APPROACH TO CUSHING’S SYNDROME OR DISEASE

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    Numerous studies and reviews agree about the increased cardiovascular risk in Cushing’s syn-drome. Therefore, the aim of the paper is to suggest a few common diagnostic and therapeutic cardiologic preferences for the majority of Cushing’s syndrome/Cushing’s disease (CS/CD) pa-tients which are not yet routine but have the rationale to become standard procedures. This may serve as an initial working document, to be improved by the experts in the field. A narrative review is used to present synthesis and deduction of several approaches in cardiology regarding the actu-al topic. Results are systematized as the risk factors or co-morbidities list (prevalent in CS/CD) coupled with current and adapted cardiologic suggestions for practice

    New Results on Pb-Au Collisions at 40 AGeV from the CERES/NA45 Experiment

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    In 1999 the CERES/NA45 ran at the CERN SPS with a beam energy of 40 GeV/nucleon. The data set comprises about 8.7 millions Pb-Au events with a trigger selection corresponding to approximately the most central 30% of the geometrical cross section. Results on low-mass electron pair analysis are presented. The upgrade of the experimental setup with the radial drift TPC has allowed to enhance hadron physics capabilities of the experiment. New results on hadron spectra (including Lambda) and flow are presented.Comment: Talk at the International Nuclear Physics Conference INPC2001, Berkeley, CA, July 29th - August 3rd 200

    Universal Pion Freeze-out in Heavy-Ion Collisions

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    Based on an evaluation of data on pion interferometry and on particle yields at mid-rapidity, we propose a universal condition for thermal freeze-out of pions in heavy-ion collisions. We show that freeze-out occurs when the mean free path of pions lambda_f reaches a value of about 1 fm, which is much smaller than the spatial extent of the system at freeze-out. This critical mean free path is independent of the centrality of the collision and beam energy from AGS to RHIC.Comment: 5 pages, 3 figures, revised version resubmitted to PR
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