High-damping carbon nanotube hinged micromirrors

New developments in digital mirror devices (DMDs) require suspension hinges with a good damping and high temperature stability. Carbon nanotubes (CNTs) offer these unique properties. Herein it is shown how CNT hinges can be integrated in micromirrors. The image illustrates a micromirror with a CNT suspension, and a typical overdamped stepresponse (Q-factor < 0.5).     

Physicochemical properties and cellular toxicity of (poly)aminoalkoxysilanes-functionalized ZnO quantum dots

Luminescent ZnO nanocrystals were synthesized by basic hydrolysis of Zn(OAc)(2) in the presence of oleic acid and then functionalized with (poly)aminotrimethoxysilanes in the presence of tetramethylammonium hydroxide to render the QDs water-dispersible. The highest photoluminescence quantum yield (17%) was achieved using N(1)-(2-aminoethyl)-N(2)-[3-(trimethoxysilyl)propyl]-1,2-ethanediamine as surface ligand. Transmission electron microscopy and powder x-ray diffraction showed highly crystalline materials with a ZnO nanoparticle diameter of about 4?nm. The cytotoxicity of the different siloxane-capped ZnO QDs towards growing Escherichia coli bacterial cells was evaluated in MOPS-minimal medium. Although concentrations of 5?mM in QDs caused a complete growth arrest in E.?coli, siloxane-capped ZnO QDs appeared weakly toxic at lower doses (0.5 or 1?mM). The concentration of bioavailable Zn (2+) ions leaked from ZnO QDs was evaluated using the biosensor bacteria Cupriavidus metallidurans AE1433. The results obtained clearly demonstrate that concentrations of bioavailable Zn(2+) are too low to explain the inhibitory effects of the ZnO QDs against bacteria cells at 1?mM and that the siloxane shell prevents ZnO QDs from dissolution contrary to uncapped ZnO nanoparticles. Because of their low cytotoxicity, good biocompatibility, low cost and large number of functional amine end groups, which makes them easy to tailor for end-user purposes, siloxane-capped ZnO QDs offer a high potential as fluorescent probes and as biosensors.     

Preferential killing of cancer cells using silicon carbide quantum dots

Silicon carbide quantum dots are highly luminescent biocompatible nanoparticles whose properties might be of particular interest for biomedical applications. In this study we investigated Silicon Carbide Quantum Dots (3C-SiC QDs) cellular localisation and influence on viability and proliferation on oral squamous carcinoma (AT-84 and HSC) and immortalized cell lines (S-G). They clearly localize into the nuclei, but the presence of 3C-SiC QDs in culture medium provoke morphological changes in cultured cells. We demonstrate that 3C-SiC QDs display dose- and time-dependent selective cytotoxicity on cancer versus immortalized cells in vitro. Since one of the limitations of classical antineoplastic drugs is their lack of selectivity, these results open a new way in the search for antiproliferative drugs.     

Hydro-mechanical loading and compressibility of fibrous media for resin infusion processes

The modelling of composite manufacturing processes where hydro-mechanical coupling takes place depends on the validity of compressibility and permeability models. In this work, the computer code initially used to simulate the effect of coupled hydro-mechanical load on composite preform (Ouahbi et al. Composites Part A, 38:1646–1654, 2007) is integrated into an inverse method to predict the compaction behaviour of the reinforcements. An experimental device developed at Le Havre is used to apply hydro-mechanical loads to the preforms. Two ramps of stress are imposed to the preform and the thickness evolution is measured as a function of time. The speed of thickness reduction is not constant and varies in the range of 0.1 to 12 mm/min. The effect of compression speed upon the saturated fabrics is investigated. For a fixed fibre volume fraction, an increase in stress is observed in increasing compression speed. The experimental results are compared to the compressibility curves determined by an inverse method. The calculated curves correspond to the compressibility curves experimentally obtained with low compression speed (～0.25 mm/min). As a consequence, this suggests that a low compression speed should be applied when investigating the compressibility behaviour of composite preform with a view of modelling resin infusion processes.     

American Psychological Association annual report.

Presents the 2009 American Psychological Association annual report. It highlights a very important year for APA and psychology by summarizing activities within each directorate. It describes strides made toward the goal of infusing psychology into the health care marketplace and of bringing psychology—and the unique skills of psychologists—to the attention of the public. This report aims to give insight into the contributions psychologists make to our communities and our country. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

William Q. Hua: APA/APAGS award for distinguished graduate student in professional psychology.

The American Psychological Association 2010 APA/APAGS Award for Distinguished Graduate Student in Professional Psychology was awarded to William Q. Hua, for his outstanding work to reduce stigma and improve wellness in marginalized communities living with HIV/ AIDS. As a concerned mental health care provider, he has modeled the commitment necessary to bring about change in health disparities experienced by minority populations and communities of color. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A point model for the design of a sulfur trioxide decomposer for the SI cycle and comparison with a CFD model

Operating under the harsh environment with the significant energy consumption, the sulfur trioxide decomposer is one of the most important components, yet challenging tasks for the designers of an efficient SI cycle. We developed a point model to provide important guidelines for designers of a sulfur trioxide decomposer through estimating outlet physical quantities, such as outlet decomposition ratio, outlet temperature, and pressure drop of a sulfur trioxide decomposer. Then, results of the point model were compared to independent predictions obtained using a CFD model over a wide range of conditions with good agreement. The model indicates that decomposition ratio is a function of the representative non-dimensional design parameter and inlet flow composition. As inlet flow composition rarely affects outlet decomposition ratio, we found out that outlet decomposition ratio can be approximated solely as a function of the non-dimensional design parameter. We demonstrated that the model can provide general guidelines for designers of a sulfur trioxide decomposer to achieve a target decomposition ratio with an economical design. It turns out that an increase in operating pressure and catalyst surface area leads to an increase in outlet decomposition ratio while the reverse is true for an increase in mass flow rate.     

Emotion regulation and vulnerability to depression: Spontaneous versus instructed use of emotion suppression and reappraisal.

Emotion dysregulation has long been thought to be a vulnerability factor for mood disorders. However, there have been few empirical tests of this idea. In this study, we tested the hypothesis that depression vulnerability is related to difficulties with emotion regulation by comparing recovered-depressed and never-depressed participants (N = 73). In the first phase, participants completed questionnaires assessing their typical use of emotion regulation strategies. In the second phase, sad mood was induced using a film clip, and the degree to which participants reported to have spontaneously used suppression versus reappraisal to regulate their emotions was assessed. In the third phase, participants received either suppression or reappraisal instructions prior to watching a second sadness-inducing film. As predicted, suppression was found to be ineffective for down-regulating negative emotions, and recovered-depressed participants reported to have spontaneously used this strategy during the first sadness-inducing film more often than controls. However, the groups did not differ regarding the effects of induced suppression versus reappraisal on negative mood. These results provide evidence for a role for spontaneous but not instructed emotion regulation in depression vulnerability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)