Effects of the Binomial Field Distribution on Collapse and Revival Phenomena in the Jaynes-Cummings Model

Abstract

The dynamical properties of a two-level atom interacting with a single non-decaying mode of an electromagnetic field in a binomial state are studied. The statistical aspects of the field, such as intensity-intensity correlation and squeezing, are also investigated. The binomial state reduces to a pure number state and a pure coherent state in different limits. Hence it enables us to study how the sinusoidal Rabi oscillations in a pure number state develop to give rise to the phenomenon of collapse and revival which has been studied extensively in the coherent-state field. In addition, the binomial state exhibits squeezing for certain values of parameters, but it is not a minimum-uncertainty-product state.     

Preparation, electrical conductivity, and magnetic susceptibility of (Ba1 − x Bi x )(Mn0.5 + x/2Nb0.5 − x/2)O3

(Ba_{1 ? x} Bi _x )(Mn_{0.5 + x/2}Nb_{0.5 ? x/2})O₃ perovskite solid solutions have been prepared by solid-state reactions and their physicochemical properties have been investigated. We have studied the influence of bismuth substitution for barium cations on the phase composition of the samples. Their magnetic susceptibility and electrical conductivity have been measured as functions of temperature. The composition dependence of the antiferromagnetic ordering temperature is presented.     

Room temperature synthesis and characterization of polythiophene thin films by chemical bath deposition (CBD) method

Polythiophene thin films were deposited successfully on glass substrate by chemical bath deposition method using FeCl₃ as an oxidant and chloroform as solvent. The effect of oxidant concentration on the properties of polythiophene thin films was studied. The surface morphology was influenced by oxidant concentration and deposition time. The oxidation concentration also strongly affects the optical properties of the polythiophene thin films. The transmittance decreases while the absorption, band gap and refractive index increases due to increase in oxidant concentration.     

Fully dense hot pressed calcium cobalt oxide ceramics

The processing parameters have been optimized to achieve highly pure and fully dense pellets of calcium cobalt oxide (Ca₃Co₄O₉) from solid-state ball milled calcium carbonate and cobalt oxide mixtures, calcined at optimized temperature and time, and consolidated by hot-pressing. The microscopic, spectroscopic, and thermal analysis suggest samples with longer ball-milling time require less calcination time for synthesizing highly pure crystalline phases of Ca₃Co₄O₉, and provide 99.2 ± 0.5% relative density.     

Temperature measurements in steady axisymmetric partially premixed flames by use of rainbow schlieren deflectometry

We focus on the utility of rainbow schlieren as a tool for measuring the temperature of axisymmetric partially premixed flames (PPFs). Methane-air PPFs are established on a coannular burner. The flames involve two spatially distinct reaction zones, one in an inner premixed region that has a curved tip and a spatially planar wing portion and another that involves an outer nonpremixed zone in which intermediate species burn in air. Schlieren images are found to visualize clearly these PPF characteristics through light deflection by steep refractive-index gradients in the two reaction zone fronts. The temperature distributions of two flames established at fuel-rich mixture equivalence ratios of phi(r) = 1.5 and 2.0, with bulk-averaged velocities, Vreac = 60 cm s(-1) and Vair = 50 cm s(-1), are inferred from color schlieren images, and a measurement error analysis is performed. Errors arise from two sources. One lies in the process of inferring the temperature from the refractive-index measurement by making assumptions regarding the local composition of the flame. We have shown through simulations that the average temperature deviations due to these assumptions are 1.7% for the phi(r) = 1.5 flame and 2.3% for the phi(r) = 2.0 flame. Another source involves the local uncertainty in the measurement of the transverse ray displacement at the filter plane that is used to determine the refractive index and thereafter the flame temperature. We have ascertained that a maximum error of 4.3% in the temperature determination can be attributed to this local measurement uncertainty. This investigation demonstrates the capability of the schlieren technique for providing not only qualitative displays of the PPFs but also full-field-of-view temperature measurements that are accurate, spatially resolved, and nonintrusive.     

Perimetric motion thresholds are elevated in glaucoma suspects and glaucoma patients

The purpose of this study was to determine if a clinically feasible perimetric motion test utilizing random-dot kinematograms could identify glaucomatous visual field defects. Using a staircase procedure, an automated perimetric motion test and a larger foveally presented target were given to normal (n = 30), glaucoma suspects (n = 31) and primary open-angle glaucoma patients (n = 19). Motion thresholds at specific locations throughout the whole visual field were significantly elevated in glaucoma patients (P < or = 0.001). Perimetric motion testing identified 84.2% of the primary open-angle glaucoma patients and 25.8% of the glaucoma suspects as abnormal. A larger foveal stimulus was unable to distinguish between the different subject groups (P < or = 0.185). Perimetric motion thresholds were significantly correlated with Humphrey standard visual field thresholds in the glaucoma and glaucoma-suspect patients (P < or = 0.0002).     

Integrated services for treatment of schizophrenic substance abusers: demographics, symptoms, and substance abuse patterns

We have previously described a model of outpatient integrated treatment for patients with comorbid psychoactive substance use disorders and schizophrenia (PSUD/S)(1). Here we review relevant literature on comorbidity and outline the rationale for integrated services. Further, we describe results from 3 related studies: First, we document the approximate incidence of PSUD among a heterogeneous group of 602 schizophrenic inpatient admissions to our hospital. Second, we describe in greater detail the psychiatric symptoms and patterns of substance abuse among a subsample of 106 inpatients with PSUD/S, contrasting them with 112 patients with PSUD and mixed psychotic disorders, but who are not schizophrenic. Third, we present a prospective research project and describe a sample of 30 patients with PSUD/S, detailing demographic characteristics, psychiatric symptoms and substance abuse history. Attention is given to current issues in the differential diagnosis of patients with PSUD/S using standardized instruments.     

Hirschsprung''s disease: a search for etiology

Expression of proliferating cell nuclear antigen (PCNA) as well as p53, bcl-2 and C-erb B-2 genes protein products on Reed-Sternberg/Hodgkin's (R-S/H) cells was analyzed by immunohistochemistry in 65 patients with Hodgkin's disease (HD). Their significance as markers of clinical malignancy and prognostic factors was evaluated. Positive reaction for PCNA was present in 57 cases (87.7%), for p53 in 42 (64.6%), for bcl-2 in 41 (63.1%), and for C-erb B-2 in 38 cases (58.5%) of HD. The high proliferate PCNA index and high expression of p53 and bcl-2 correlated with poor response to the treatment. Expression of both p53 and bcl-2 oncoproteins negatively influenced overall survival and disease free survival. Indexes of PCNA, p53 and bcl-2 were significantly higher in patients with advanced disease then in early clinical stages. In LP type of HD the lowest indexes of PCNA or bcl-2, and even lack of bcl-2 expression on R-S/H cells were observed. There was no correlation between expression of C-erb B-2 and response to the treatment, time of survival, clinical stage or histopathological types of HD. Statistical analysis let us to the conclusion, that indexes of PCNA, p53 and bcl-2 expression can be taken into consideration as a new prognostic factors in Hodgkin's disease. C-erb B-2 protein expression seems to be of no value for prognosis in HD.