Evaluation of the Effects of Developmental Trauma on Neurotransmitter Systems Using Functional Molecular Imaging

Early life stress (ELS) is strongly associated with psychiatric disorders such as anxiety, depression, and schizophrenia in adulthood. To date, biological, behavioral, and structural aspects of ELS have been studied extensively, but their functional effects remain unclear. Here, we examined NeuroPET studies of dopaminergic, glutamatergic, and serotonergic systems in ELS animal models. Maternal separation and restraint stress were used to generate single or complex developmental trauma. Body weights of animals exposed to single trauma were similar to those of control animals; however, animals exposed to complex trauma exhibited loss of body weight when compared to controls. In behavioral tests, the complex developmental trauma group exhibited a decrease in time spent in the open arm of the elevated plus-maze and an increase in immobility time in the forced swim test when compared to control animals. In NeuroPET studies, the complex trauma group displayed a reduction in brain uptake values when compared to single trauma and control groups. Of neurotransmitter systems analyzed, the rate of decrease in brain uptake was the highest in the serotonergic group. Collectively, our results indicate that developmental trauma events induce behavioral deficits, including anxiety- and depressive-like phenotypes and dysfunction in neurotransmitter systems.     

EXPERIMENTAL ESTIMATION OF A SCALING EXPONENT FOR TIP VORTEX CAVITATION VIA ITS INCEPTION TEST IN FULL- ANDMODEL-SHIP

Tip vortex cavitation noise of marine propeller became primary concerns to reduce hazardous environmental impacts from commercial ship or to keep the underwater surveillance of naval ships. The investigations of the tip vortex and its induced noise are normally conducted through the model test in a water cavitation tunnel. However the Reynolds number of model-test is much smaller than that of the full-scale, which subsequently results in the difference of tip vortex cavitation inception. Hence, the scaling law between model-and full-scales needs to be identified prior to the prediction and assessment of propeller noise in full scale. From previous researches, it is generally known that the incipient caivtation number of tip vortex can be represented as a power of the Reynolds number. However, the power exponent for scaling, which is the main focus of this research, has not been clearly studied yet. This paper deals with the estimation of scaling exponent based on tip vortex cavitation inception test in both full-and model-scale ships. Acoustical measurements as well as several kind of signal processing technique for an inception criterion suggest the scaling exponent as 0.30. The scaling value proposed in this study shows slight difference to the one of most recent research. Besides, extrapolation of model-ship noise measurement using the proposed one predicts the full-scale noise measurement with an acceptable discrepancy.     

Photocatalytic degradation of methylene blue and acetaldehyde by TiO<Subscript>2</Subscript>/glaze coated porous red clay tile

Nanosized TiO₂ sol synthesized by sol-gel method was successfully coated on the porous red clay tile (PRC tile) with micrometer sized pores. PRC tile was first coated with a low-firing glaze (glaze-coated PRC tile) and then TiO₂ sol was coated on the glaze layer. A low-fired glaze was prepared at various blending ratios with frit and feldspar, and a blending ratio glazed at 700 °C was selected as an optimum condition. Then TiO₂ sol synthesized from TTIP was dip-coated on the glazed layer (TiO₂/glaze-coated PRC tile), and it was calcined again at 500 °C. Here, these optimum calcination temperatures were selected to derive a strong bonding by a partial sintering between TiO₂ sol particles and glaze layer. Photocatalytic activity on the TiO₂/glaze-coated PRC tile was evaluated by the extent of photocatalytic degradation of methylene blue and acetaldehyde. Methylene blue with the high concentration of 150 mg/l on the surface of TiO₂/glaze-coated PRC tile was almost photodegraded within 5 hours under the condition of average UV intensity of 0.275 mW/cm₂, while no photodegradation reaction of methylene blue occurred on the glaze-coated PRC tile without TiO₂. Another photocatalytic activity was also evaluated by measuring the extent of photocatalytic degradation of gaseous acetaldehyde. The photodegradation efficiency in TiO₂/glaze-coated PRC tile showed about 77% photocatalytic degradation of acetaldehyde from 45,480 mg/l to 10,536 mg/l after the UV irradiation of 14 hours, but only about 16% in the case of the glaze-coated PRC tile.     

Adsorption and thermodesorption characteristics of benzene in nanoporous metal organic framework MOF-5

This study has been prepared and characterized a highly nanoporous metal organic framework (MOF-5). The nitrogen adsorption isotherm, gravimetric adsorption and thermodesorption method that utilize a quartz spring balance are used to examine the unusual adsorption behavior. Especially, the hybrid Langmuir–Sips isotherm equation is employed to correlate the experimental isotherm data. Moreover, the unusual adsorption behavior in MOF-5 is discussed in relation to its isosteric enthalpy of adsorption, adsorption energy distribution and desorption energy distribution calculated from benzene adsorption and thermodesorption measurements.     

Improved calibration method for SDINS considering body-frame drift

A calibration method for a strap-down inertial navigation system (SDINS) is presented here. The body-frame drift induced by the variation of the accelerometer sensing axe due to temperature changes is an important source of navigation error not considered in conventional calibration methods. In this paper, we propose an advanced calibration method that can compensate for SDINS error sources including not only bias, scale factor, and misalignment but also the body-frame drift by utilizing a 2-axis turntable. The body-frame drift is estimated using horizontal accelerometer measurements during a calibration procedure. Simulation results show that the body-frame drift behaves like an additional gyro bias error and that the proposed calibration technique can significantly improve pure navigation performance by removing the effect of body-frame drift.     

Nanocrystalline TiO2 films treated with acid and base catalysts for dye-sensitized solar cells

Crystalline size and porosity of TiO₂ films are known to be easily controlled by changing acid or base catalyst concentration. This work investigates the influence of acid/base catalyst treatments of TiO₂ nanoparticles on the efficiency of dye-sensitized solar cells (DSSCs). The results indicate that the performance of DSSC fabricated with base-treated TiO₂ is remarkably better than that fabricated with acid-treated TiO₂ because of different film properties including particle size, shape, film porosity, and surface structure and electron transport phenomena.     

Fabrication and characterization of electrospun Ag doped TiO2 nanofibers for photocatalytic reaction

Titanium dioxide is one of the best semiconductor photocatalysts available for photocatalytic reaction of dye pollutants. To prevent the recombination caused by the relatively low photocatalytic efficiency, Ag doped TiO₂ nanofiber was prepared by electrospinning method. The photocatalysts (pure TiO₂ nanofiber and Ag doped TiO₂ nanofiber) were characterized by FE-SEM, XRD, XPS, and PL analysis. These photocatalysts were evaluated by the photodecomposition of methylene blue under UV light. Ag doped TiO₂ nanofiber was found to be more efficient than pure TiO₂ fiber for photocatalytic degradation of methylene blue. The photocatalytic degradation rate was applied to pseudo-first-order equation. The degradation of Ag doped TiO₂ nanofiber was significantly higher than the degradation rate of pure TiO₂ nanofiber. Activation energy was calculated by applying Arrhenius equation from the rate constant of photocatalytic reaction. The activation energies for the pure TiO₂ nanofibers calcined at 400 and 500 °C were 16.981 and 12.187 kJ/mol and those of Ag doped TiO₂ nanofibers were 18.317 and 7.977 kJ/mol, respectively.     

Photocurrent-voltage of a dye-sensitized nanocrystalline TiO2 solar cells influenced by N719 dye adsorption properties

Titanium particles of single-phase anatase nanocrystallites were prepared by the hydrolysis of titanium tetraisopropoxide. A dye-sensitized solar cell (DSSC) was fabricated by adsorbing cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium dye (N719) onto TiO2 film. The samples were characterized by XRD, TEM, FE-SEM, AFM, and Brunauer-Emmett-Teller (BET) analysis. The influence of the acetic acid treatment of TiO2 electrode with different concentrations on the photovoltaic performance of DSSC was investigated. It was found that DSSC had better photoelectric performance when the TiO2 electrode was treated by acetic acid of 0.5 M. An equivalent circuit analysis using the one-diode model was used to evaluate the influences of adsorption quantity and acetic acid treatment on the energy conversion efficiency of DSSC. A nonlinear least-square optimization method was used to determine five model parameters.     

Hydrochloric acid treatment of TiO2 electrode for quasi-solid-state dye-sensitized solar cells

Quasi-solid-state dye-sensitized solar cell was fabricated by sandwiched polymer electrolyte containing liquid electrolytes between the dye-sensitized TiO2 electrode and a Pt electrode. The influence of hydrochloric acid treatment of TiO2 photoelectrode on the photoelectronic performance was investigated. Quasi-solid-state dye-sensitized solar cell showed better photoelectronic performance when the TiO2 electrode was treated with hydrochloric acid than that without treatment. The short-circuit current density (J(sc)), the open-circuit voltage (V(oc)), and a conversion efficiency obtained for an incident light intensity of 100 mW m(-2) were 6.49 mA cm(-2), 0.76 V and 4.1%, respectively. It was found that the hydrochloric acid treatment of TiO2 electrode increased the short-circuit current density and cell efficiency.