Classification of rheumatoid joint inflammation based on laser imaging

We describe a classification system for a novel imaging method for arthritic finger joints. The basis of this system is a laser imaging technique which is sensitive to the optical characteristics of finger joint tissue. From the laser images acquired at baseline and follow-up, finger joints can automatically be classified according to whether the inflammatory status has improved or worsened. To perform the classification task, various linear and kernel-based systems were implemented and their performances were compared. Based on the results presented in this paper, we conclude that the laser-based imaging permits a reliable classification of pathological finger joints, making it a sensitive method for detecting arthritic changes.     

Dual lifetime referencing as applied to a chloride optical sensor

A membrane with an optical response to chloride has been developed that contains two luminophores that display two largely different decay times. The first luminophore (the "reference") is a chloride-insensitive ruthenium metal-ligand complex possessing a decay time in the microsecond range. The second luminophore is the short-lived chloride-quenchable fluorescent probe lucigenin. Both are contained in a hydrogel matrix and are excited by a blue LED emitting sinusoidally modulated light. Under these conditions, the chloride-dependent fluorescence intensity of lucigenin can be converted in an analyte-dependent fluorescence phase shift that depends on the ratio of the two luminescence intensities and can be measured at modulation frequencies of typically 45 kHz. The dynamic range of this sensor can be adjusted by either varying the ratio of the two luminophores or selecting a particular optical filter combination.     

Fluorescent imaging of pH with optical sensors using time domain dual lifetime referencing

We present a referenced scheme for fluorescence intensity measurements that is useful for imaging applications. It is based on the conversion of the fluorescence intensity information into a time-dependent parameter. A phosphorescent dye is added in the form of approximately 10-microm particles to the sample containing the pH-sensitive fluorescent indicator. Both the reference dye and the pH probe are excited simultaneously by a blue LED, and an overall luminescence is measured. In the time-resolved imaging method presented here, two images taken at different time gates were recorded using a CCD camera. The first image is recorded during excitation and reflects the luminescence signal of both the fluorophore (pH) and the phosphor (reference). The second image, which is measured after a certain delay (after switching off the light source), is solely caused by the long-lived phosphorescent dye. Because the intensity of the fluorophore contains the information on pH, whereas phosphorescence is pH-independent, the ratio of the images displays a referenced intensity distribution that reflects the pH at each picture element (pixel). The scheme is useful for LED light sources and CCD cameras that can be gated with square pulses in the microsecond range. The fundamentals and potential of this new method, to which we refer as time domain dual lifetime referencing (t-DLR), are demonstrated.     

Longitudinal study of social support and meaning in life.

The purpose of this study was to see whether 3 types of social support (enacted support, negative interaction, and anticipated support) are associated with change in meaning in life. Data from a nationwide longitudinal survey of older people suggested that greater anticipated support (i.e., the belief that others will provide assistance in the future if needed) is associated with a deeper sense of meaning over time. The same was true with respect to emotional support received from family members and close friends. In contrast, the findings revealed that, at least initially, negative interaction lowers an older person's sense of meaning in life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Longitudinal factor structure of posttraumatic stress symptoms related to intimate partner violence.

Confirmatory factor analysis (CFA) studies have suggested that a model of posttraumatic stress disorder (PTSD) that is characterized by 4 factors is preferable to competing models. However, the composition of these 4 factors has varied across studies, with 1 model splitting avoidance and numbing symptoms (e.g., D. W. King, G. A. Leskin, L. A. King, & F. W. Weathers, 1998) and the other including a dysphoria factor that combines numbing and nonspecific hyperarousal symptoms (L. J. Simms, D. Watson, & B. N. Doebbeling, 2002). Using the PTSD Checklist (F. W. Weathers, B. T. Litz, D. S. Herman, J. A. Huska, & T. M. Keane, 1993) and CFA, the authors compared these models with competing models. A model of PTSD with 4 intercorrelated factors of Intrusions, Avoidance, Dysphoria, and Hyperarousal was found superior among 396 medical patients who screened positive for intimate partner violence (IPV) and 405 women seeking services for IPV. Structural invariance testing indicated that this 4-factor model remains stable across service setting and time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of platinum salt concentration on the electrospinning of polyacrylonitrile/platinum acetylacetonate solution

The preparation and characterization of electrospun polyacrylonitrile (PAN)/platinum(II) acetylacetonate composite nanofibers were investigated. The solution properties, such as viscosity, surface tension, and conductivity, of Pt‐acetylacetonate‐added PAN solutions in N,N‐dimethylformamide were measured, and their influences on the resulting fiber structure were also determined. At low Pt salt concentrations, the addition of Pt salt increased the fiber diameter but did not change the fiber diameter distribution. However, the fiber diameter decreased, and the fiber diameter distribution became broader when the Pt salt concentration went beyond a critical value. The structure of the electrospun fibers was determined by the formation of polymer–salt– solvent interactions, which changed the balance among the viscosity, surface tension, and conductivity of the solutions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

A comparison of alternate immunization regimes for measles in vaccinated populations

Infants today lose maternal measles antibody sooner than in the past. This is related to demographic changes in maternal immunization. Data for rates of decay of maternal antibody and seroconversion after measles vaccination for infants born to naturally immune (Group 1) or vaccinated (Group 2) mothers have been used to evaluate two vaccination schedules: Regime 1, measles-mumps-rubella (MMR) at 1 year of age and Regime 2, monovalent measles at 6 months followed by MMR at 15 months of age. Regime 2 costs less because MMR can be administered at 15 months with the last pentavalent booster. Months of protection/1000 children aged 0-15 months (child-months of protection) were estimated for infant populations ranging from 0 to 100% Group 1 for Regimes 1 and 2. Regime 1 provides more child-months of protection only for 100% Group 1 populations. For the study population Regime 2 provided at least 17% more child-months of protection than Regime 1. Regime 2 provides increased medical and financial benefits in proportion to the number of Group 2 infants in the population and thus is ever more advantageous for today's increasingly vaccinated populations.     

Fabrication, Characterization and Application of Polymer Nanocomposites for Arsenic(III) Removal from Water

Polymer nanocomposites constituted of [ethylene-vinyl acetate (EVA) (70 %) polycaprolactone (PCL) (15 %) Fe₃O₄ (15 %)] were synthesized and applied in the removal of Arsenic(III) from contaminated water. Arsenic contamination in water is a severe problem globally because arsenic is toxic even at low concentrations. The aim of this study is to incorporate magnetite (Fe₃O₄) into a polymer blend that is to be used as an adsorbent for the removal of As(III). In this study EVA–PCL copolymers with magnetite were synthesized via the melt blending technique. The nanocomposites were characterized by the use scanning electron microscopy, thermogravimetry analysis and X-ray diffraction. Batch experiments were carried out to investigate the ability of polymer nanocomposites to adsorb As(III) from contaminated water. A maximum sorption capacity of 2.83 mg/g at 26 ± 2 °C and pH 8.6 was obtained. Adsorption data were fitted to Langmuir, Freundlich and Dubinin–Radushkevich isotherms. The process fits well with the Langmuir isotherm. As(III) obeyed pseudo-second order kinetics. The nanocomposites investigated in this study showed good potential for As(III) removal from contaminated water. The dispersion of magnetite nanoparticles into the polymers resulted with improved surface area for better adsorption of As(III).