Submillisecond response nematic liquid crystal modulators using dual fringe field switching in a vertically aligned cell

A fast response nematic liquid crystal (LC) modulator using dual fringe field switching (DFFS) mode is demonstrated. Both top and bottom substrates have pixel and common electrodes to generate complementary fringing fields. The cell consists of a vertically aligned LC layer whose dielectric anisotropy is positive. In a voltage-on state, self-imposed thin LC walls near the center of the slits and electrodes are formed and the surrounding LC molecules exert a strong restoring force. As a result, submillisecond gray-to-gray response time is achieved. Two DFFS cells are used as examples to illustrate the design principles for display and photonic applications. (C) 2008 American Institute of Physics

Baicalein antagonizes rotenone-induced apoptosis in dopaminergic SH-SY5Y cells related to Parkinsonism

<p>Abstract</p> <p>Background</p> <p>Two active compounds, baicalein and its glycoside baicalin were found in the dried root of <it>Scutellaria baicalensis </it>Georgi, and reported to be neuroprotective <it>in vitro </it>and <it>in vivo</it>. This study aims to evaluate the protective effects of baicalein on the rotenone-induced apoptosis in dopaminergic SH-SY5Y cells related to parkinsonism.</p> <p>Methods</p> <p>Cell viability and cytotoxicity were determined by MTT assay. The degree of nuclear apoptosis was evaluated with a fluorescent DNA-binding probe Hoechst 33258. The production of reactive oxidative species (ROS) and loss of mitochondrial membrane potential (ΔΨm) were determined by fluorescent staining with DCFH-DA and Rhodanmine 123, respectively. The expression of Bax, Bcl-2, cleaved caspase-3 and phosphorylated ERK1/2 was determined by the Western blots.</p> <p>Results</p> <p>Baicalein significantly increased viability and decreased rotenone-induced death of SH-SY5Y cells in a dose-dependent manner. Pre- and subsequent co-treatment with baicalein preserved the cell morphology and attenuated the nuclear apoptotic characteristics triggered by rotenone. Baicalein antagonized rotenone-induced overproduction of ROS, loss of ΔΨm, the increased expression of Bax, cleaved caspase-3 and phosphorylated ERK1/2 and the decreased expression of Bcl-2.</p> <p>Conclusion</p> <p>The antioxidative effect, mitochondrial protection and modulation of anti-and pro-apoptotic proteins are related to the neuroprotective effects of baicalein against rotenone induced cell death in SH-SY5Y cells.</p

High ambient-contrast-ratio display using tandem reflective liquid crystal display and organic light-emitting device

A high ambient-contrast-ratio (A-CR) and large aperture-ratio display is conceptually demonstrated and experimentally validated by stacking a normally black reflective liquid crystal display (NB-RLCD) and an organic light-emitting device (OLED). Such a tandem device can be switched between the NB-RLCD mode and the OLED mode under bright and dark ambient light, respectively. The normally black characteristic of the RLCD also helps to boost the A-CR under OLED-mode operation. To obtain a better image quality in the RLCD mode, a bumpy and transmissive structure is used to eliminate the specular reflection and to increase the viewing angle performance that results in CR \u3e 2:1 over 55 degrees viewing cone. Besides, such a structure can also increase the external quantum efficiency of the OLED by 49.4%. In our experiments, regardless of the ambient intensity the A-CR is kept higher than 100:1

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

A Simple Method For Measuring The Cell Gap Of A Reflective Twisted Nematic Lcd

A simple method is demonstrated for measuring the cell gap of reflective twisted nematic (RTN) liquid crystal (LC) cells. This method utilizes a single laser beam and crossed-polarizer configuration such that Fabry-Perot effect and surface reflection are eliminated. Experimental results agree well with theory

A Single Cell Gap Transflective Lcd For Color Sequential Applications

A single cell gap transflective liquid crystal display (TR-LCD) for color sequential applications is proposed. It employs dual fringing field switching mode, in which a positive dielectric anisotropy LC is vertically aligned and driven by fringing fields from both substrates. The normalized voltage dependent transmitíame and reflectance curves overlap reasonably well with each other so that a single gamma curve can be applied. After phase compensation, this TR-LCD shows a fast response time, high optical efficiency, and wide viewing angle. The fast response time enables color sequential method to be employed which will result in tripled optical efficiency and image resolution at the transmissive part and better color saturation at the reflective part. © 2008 SID

Fast-Response Single Cell Gap Transflective Liquid Crystal Displays

A single cell gap transflective liquid crystal display (TR-LCD) using dual fringing field switching mode is proposed, in which a positive dielectric anisotropy liquid crystal is vertically aligned and driven by fringing fields from both substrates. By optimizing the electrode width and gap of the transmissive and reflective regions, this TR-LCD exhibits a fast response time, high optical efficiency, single gamma curve, and wide viewing angle. Fast response time enables color sequential operation using red, green, and blue light-emitting diodes without noticeable color breakup. Potential application of this TR-LCD for sunlight readable mobile displays is emphasized. © 2009 IEEE

Turning Older Women’s Life Stories into Hypermedia: Reflections on the Production of Feminist Creative Analytic Practices

This article discusses our development of a new form of feminist Creative Analytic Practices (CAP) by creating knowledge through interactive video installation and web-based interactive re-storytelling ( https://kimchoi.net/a-story-of-ones-own/ ). Since the 1990s, qualitative social researchers have been developing alternative methods and forms to capture and represent the complexity of lived experiences. Through referencing feminist postconstructionist CAP, Deleuzian rhizomatic narrative inquiry, and feminist film theories and films, our project – consisting of reflexive writing experiments and re-enactment of 43 older Hong Kong women’s life stories in hypermedia – contributes to this expansive knowledge. Specifically, we describe our writing and production processes, including the strategies and tools considered, medium specificity and cinematic apparatuses used, and challenges encountered when attempting to create a nonlinear, multi-layered, polyphonic, and interactive narrative. Our main concerns are: How can researchers produce a self-conscious, research-based creative work that highlights women’s agency under socio-cultural constraints, whilst acknowledging selfhood as rhizomatic, knowledge as situated, and “truths” as partial and multiple under conditions of its own making? How can we produce alternative social science research practices that carry both logic and affect? How can we engage the audience to open up and interpret older women’s life stories in embodied and experiential ways