To improve the morphological and electro‐optical properties of a polymer‐dispersed liquid crystal (PDLC) grating, a type of highly fluorine‐substituted acrylate monomer was added to the prepolymer mixture. The morphologies of the PDLC... more
To improve the morphological and electro‐optical properties of a polymer‐dispersed liquid crystal (PDLC) grating, a type of highly fluorine‐substituted acrylate monomer was added to the prepolymer mixture. The morphologies of the PDLC gratings were investigated using ...
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ABSTRACT
An integral part of drug discovery and development is the identification of drug metabolites that indicate intrinsic pharmacokinetic mechanism, pharmacological activity or specific toxicity. We describe the use of MSM, which utilizes... more
An integral part of drug discovery and development is the identification of drug metabolites that indicate intrinsic pharmacokinetic mechanism, pharmacological activity or specific toxicity. We describe the use of MSM, which utilizes multiple collision cells, dissociation methods, scan modes, mass analyzers and detectors to perform intelligent metabolite identification experiments. A modified LTQ Orbitrap XL with an HCD (Higher-energy Collisional Dissociation) collision cell was used. An isolation mass window up to 600 amu for HCD scans was enabled. In this experiment, a high resolution full scan was acquired followed by a high resolution HCD MS/MS of all incoming ions within that 600amu window. In parallel, the linear ion trap (LIT) acquired data dependent MSn spectra. Accela UPLC and Hypersil Gold C18 column(1x100mm, 1.9m) with a 20-minute gradient was used. 10M and 1M of rat and human hepatocytes incubation samples from verapamil and haloperidol were analyzed. The performance of ...
Abstract: Cell migration plays the essential role in embryogenesis, wound healing, immunization, infection, and cancer metastasis. To study actions of cell migration-associated genes in liver regeneration, these genes were obtained by... more
Abstract: Cell migration plays the essential role in embryogenesis, wound healing, immunization, infection, and cancer metastasis. To study actions of cell migration-associated genes in liver regeneration, these genes were obtained by seaching for the related ...
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Transforming growth factor (TGF)beta is implicated in the pathogenesis of cyclosporine A (CsA) nephrotoxicity. We examined the efficacy of TGF beta receptor (R)II/immunoglobulin (Ig)G Fc, a soluble chimeric protein consisting of the... more
Transforming growth factor (TGF)beta is implicated in the pathogenesis of cyclosporine A (CsA) nephrotoxicity. We examined the efficacy of TGF beta receptor (R)II/immunoglobulin (Ig)G Fc, a soluble chimeric protein consisting of the extracellular domain of human TGF beta RII and IgG1 Fc, on CsA nephrotoxicity in mice. Subcutaneous injection of CsA (25 mg/kg/d) was given daily to mice maintained on a low-sodium diet. On days 1 and 7, an expression vector carrying cDNA for either TGF beta RII/IgG Fc or beta-galactosidase was transfected into the skeletal muscles by electroporation. At 2 or 3 weeks of CsA administration, plasma and renal TGF beta 1 levels, and tubulointerstitial injury and fibrosis were evaluated. After 2 weeks of CsA administration, plasma and renal TGF beta 1 levels increased to the maximum and then declined toward the baseline levels. Renal TGF beta 1 mRNA remained elevated until 3 weeks. Tubulointerstitial alterations became appreciable in 2 weeks and intensified b...
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Bioassay-guided fractionation of an extract prepared from Alangium javanicum using an assay to monitor Cu(2+)-dependent DNA strand scission led to the isolation of javaniside, a new type of oxindole glycoside.
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Bioassay-guided fractionation of an active organic extract of Piper caninum, using a sensitive yeast assay to monitor putative double-strand DNA-damaging activity, resulted in the isolation of the 4,5-dioxoaporphine alkaloid cepharadione... more
Bioassay-guided fractionation of an active organic extract of Piper caninum, using a sensitive yeast assay to monitor putative double-strand DNA-damaging activity, resulted in the isolation of the 4,5-dioxoaporphine alkaloid cepharadione A (1). Compound 1 exhibited potent inhibitory activity in a yeast cytotoxicity assay with IC(50) values of 50.2 nM toward RS321NpRAD52 grown on glucose versus 293 nM toward the same yeast strain grown on galactose.
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A crude extract prepared from roots of Mallotus resinosus exhibited significant Cu(2+)-dependent DNA strand scission activity and was thus selected for bioassay-guided fractionation. Scopoletin (1), a simple coumarin, was identified as... more
A crude extract prepared from roots of Mallotus resinosus exhibited significant Cu(2+)-dependent DNA strand scission activity and was thus selected for bioassay-guided fractionation. Scopoletin (1), a simple coumarin, was identified as the active principle responsible for DNA cleavage activity of the crude extract. The DNA strand scission activity of 1, as well as that of three structural analogues, is reported.
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Over-expression of RhoA in esophageal squamous cell carcinoma (ESCC) indicates a poor prognosis and is correlated with the tumor-node-metastasis (TNM) clinical classification. However, until now RhoA function in the ESCC progression... more
Over-expression of RhoA in esophageal squamous cell carcinoma (ESCC) indicates a poor prognosis and is correlated with the tumor-node-metastasis (TNM) clinical classification. However, until now RhoA function in the ESCC progression remains to be established. We employed adenovirus-mediated small hairpin RNA (shRNA) against human RhoA (Ad-sh-RhoA) to efficiently silence target gene expression in RhoA-expressing Eca-109 ESCC cells at both protein and mRNA levels. Consequently, Ad-sh-RhoA reduced the proliferation and migration of Eca-109 cells assayed by MTT assay and cell wound healing, respectively. Moreover, Ad-sh-RhoA increased cell apoptosis and inhibited the cell cycle G1-S-phase progression of Eca-109 cells assessed by flow cytometry. Finally, in a nude mouse model, intratumoral injections of adenovirus-delivered RhoA shRNA every 3 days for 20 days significantly inhibited the growth and angiogenesis of xenografted Eca-109 tumors. In summary, these data indicate that RhoA may b...
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Breast cancer is the most common malignancy in women in the world. High incidence and poor clinical outcomes underly the need for a better understanding of its tumor biology and how to effectively inhibit tumor progression. In the present... more
Breast cancer is the most common malignancy in women in the world. High incidence and poor clinical outcomes underly the need for a better understanding of its tumor biology and how to effectively inhibit tumor progression. In the present study the question of whether NDRG2 might be a useful target for breast cancer therapy was addressed. With the increase or decrease of NDRG2 levels in MCF-7 and Bcap-37 cells by adenovirus-NDRG2 infection or NDRG2 siRNA transfection, CD24 expression was significantly decreased or increased, respectively. Furthermore, NDRG2 overexpression suppressed breast cancer cell adhesion and invasion, whereas knockdown of NDRG2 promoted these events. In conclusion, the data from the current study indicated that NDRG2, the product of a tumor suppressor gene, can regulate CD24 expression to decrease the metastatic potential of breast cancer cells.
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ABSTRACT A innovative pretreatment technique and its kinetics for treating waste klebsiella pneumoniae strains from 1, 3-propanediol (1,3-PD) fermented product by auto thermal thermophilic aerobic digestion (ATAD) process were... more
ABSTRACT A innovative pretreatment technique and its kinetics for treating waste klebsiella pneumoniae strains from 1, 3-propanediol (1,3-PD) fermented product by auto thermal thermophilic aerobic digestion (ATAD) process were investigated in laboratory scale to inactivate and reduce pathogens, which was a pretreatment process of the up-flow anaerobic sludge bed (UASB). The feed total suspended solids (TSS), pH value, Redox potential, temperature released by self-heating, and the numbers of pathogens were conducted. The results showed that TSS removal rate and the temperature reached 62.75% and 65¿ respectively, the pathogens' removal rate was 100%, the results from new kinetic model developed for the ATAD process had a good agreement with actual results.
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We report the identification of a PDE10A clinical candidate by optimizing potency and in vivo efficacy of promising keto-benzimidazole leads 1 and 2. Significant increase in biochemical potency was observed when the saturated rings on... more
We report the identification of a PDE10A clinical candidate by optimizing potency and in vivo efficacy of promising keto-benzimidazole leads 1 and 2. Significant increase in biochemical potency was observed when the saturated rings on morpholine 1 and N-acetyl piperazine 2 were changed by a single atom to tetrahydropyran 3 and N-acetyl piperidine 5. A second single atom modification from pyrazines 3 and 5 to pyridines 4 and 6 improved the inhibitory activity of 4 but not 6. In the in vivo LC-MS/MS target occupancy (TO) study at 10 mg/kg, 3, 5, and 6 achieved 86-91% occupancy of PDE10A in the brain. Furthermore, both CNS TO and efficacy in PCP-LMA behavioral model were observed in a dose dependent manner. With superior in vivo TO, in vivo efficacy and in vivo PK profiles in multiple preclinical species, compound 5 (AMG 579) was advanced as our PDE10A clinical candidate.
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Acute myeloid leukemia (AML) remains a serious unmet medical need. Despite high remission rates with chemotherapy standard-of-care treatment, the disease eventually relapses in a major proportion of patients. Activating Fms-like tyrosine... more
Acute myeloid leukemia (AML) remains a serious unmet medical need. Despite high remission rates with chemotherapy standard-of-care treatment, the disease eventually relapses in a major proportion of patients. Activating Fms-like tyrosine kinase 3 (FLT3) mutations are found in approximately 30% of patients with AML. Targeting FLT3 receptor tyrosine kinase has shown encouraging results in treating FLT3-mutated AML. Responses, however, are not sustained and acquired resistance has been a clinical challenge. Treatment options to overcome resistance are currently the focus of research. We report here the preclinical evaluation of AMG 925, a potent, selective, and bioavailable FLT3/cyclin-dependent kinase 4 (CDK4) dual kinase inhibitor. AMG 925 inhibited AML xenograft tumor growth by 96% to 99% without significant body weight loss. The antitumor activity of AMG 925 correlated with the inhibition of STAT5 and RB phosphorylation, the pharmacodynamic markers for inhibition of FLT3 and CDK4, respectively. In addition, AMG 925 was also found to inhibit FLT3 mutants (e.g., D835Y) that are resistant to the current FLT3 inhibitors (e.g., AC220 and sorafenib). CDK4 is a cyclin D-dependent kinase that plays an essential central role in regulating cell proliferation in response to external growth signals. A critical role of the CDK4-RB pathway in cancer development has been well established. CDK4-specific inhibitors are being developed for treating RB-positive cancer. AMG 925, which combines inhibition of two kinases essential for proliferation and survival of FLT3-mutated AML cells, may improve and prolong clinical responses.
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The two‐dimensional (2D) electrically tuneable grating exhibits a bright future in the fields of optics and communication. A 2D grating based on a polymer‐dispersed liquid crystal (PDLC) with good electro‐optical (E‐O) properties was... more
The two‐dimensional (2D) electrically tuneable grating exhibits a bright future in the fields of optics and communication. A 2D grating based on a polymer‐dispersed liquid crystal (PDLC) with good electro‐optical (E‐O) properties was fabricated through a single‐step ...
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To improve the morphological and electro‐optical properties of a polymer‐dispersed liquid crystal (PDLC) grating, a type of highly fluorine‐substituted acrylate monomer was added to the prepolymer mixture. The morphologies of the PDLC... more
To improve the morphological and electro‐optical properties of a polymer‐dispersed liquid crystal (PDLC) grating, a type of highly fluorine‐substituted acrylate monomer was added to the prepolymer mixture. The morphologies of the PDLC gratings were investigated using ...
Research Interests:
ABSTRACT Anisotropic waveguide theory is developed for electrically tunable distributed feedback (DFB) laser from dye-doped holographic polymer dispersed liquid crystal (HPDLC) grating. The period grating structure, optical anisotropy of... more
ABSTRACT Anisotropic waveguide theory is developed for electrically tunable distributed feedback (DFB) laser from dye-doped holographic polymer dispersed liquid crystal (HPDLC) grating. The period grating structure, optical anisotropy of the liquid crystal (LC) and practical light propagation path in the HPDLC have been considered. The emitted lasing wavelength is deduced on basis of the dielectric anisotropy of the LC, transverse-magnetic (TM) light wave propagation in the core layer and DFB laser theory. An experimental method to determine the tilt angle of the LC and the lasing behaviours under different electric fields are used to verify the validity of the anisotropic numerical analysis. The results show that a more accurate agreement between the theoretical calculations and the experimental data is achieved. The anisotropic numerical analysis presented here is very useful when designing and optimising tunable lasers for optical communications and integrated optics.
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Research Interests: Life Sciences, Confocal Microscopy, Western blotting, Cell line, Mice, and 10 moreAldosterone, Animals, Fluorescent Antibody Technique, Epithelial cells, Western blot, Renal Fibrosis, Mineralocorticoid Receptor, Enzyme Linked Immunosorbent Assay, Biochemistry and cell biology, and Vascular Endothelial Growth Factor
... 37. Fiche JB, Laredo T, Tanchak O, Lipkowski J, Dutcher JR, Yada RY. Influence of an electric field on oriented films of DMPC/ gramicidin bilayers: a circular dichroism study. Langmuir. 2010; 26:105766. An insect antifreeze protein... more
... 37. Fiche JB, Laredo T, Tanchak O, Lipkowski J, Dutcher JR, Yada RY. Influence of an electric field on oriented films of DMPC/ gramicidin bilayers: a circular dichroism study. Langmuir. 2010; 26:105766. An insect antifreeze protein ApAFP752 from Anatolica polita 349 123
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The interfacial properties of polymer dispersed liquid crystal (PDLC) gratings influenced by partial matrix fluorination are studied through molecular dynamics methods. The miscibility between the fluorine-substituted monomer and other... more
The interfacial properties of polymer dispersed liquid crystal (PDLC) gratings influenced by partial matrix fluorination are studied through molecular dynamics methods. The miscibility between the fluorine-substituted monomer and other materials in the prepolymer mixture is evaluated by using the solubility parameters of molecules. The interfacial effect of different fluorination levels is analysed theoretically. The results indicate that most fluorine-substituted monomers are distributed on the interface between the monomer and the LC. The interaction energy on the interface decreases with increasing fluorination, which can improve the electro-optical tunable performance of such gratings. However, it should also be noted that excessive fluorination may lead to penetration of fluorine-substituted monomers into the LC medium. Such a result will block the normal diffusion of LC during the photo-initiated polymerization-induced phase separation process. Through calculation of the radial distribution function, a reasonable alignment structure for LCs near the interface is given. The calculation of the order parameter shows that fluorination causes disorder of their orientation.
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Bioassay-guided fractionation of an active organic extract of Piper caninum, using a sensitive yeast assay to monitor putative double-strand DNA-damaging activity, resulted in the isolation of the 4,5-dioxoaporphine alkaloid cepharadione... more
Bioassay-guided fractionation of an active organic extract of Piper caninum, using a sensitive yeast assay to monitor putative double-strand DNA-damaging activity, resulted in the isolation of the 4,5-dioxoaporphine alkaloid cepharadione A (1). Compound 1 exhibited potent inhibitory activity in a yeast cytotoxicity assay with IC(50) values of 50.2 nM toward RS321NpRAD52 grown on glucose versus 293 nM toward the same yeast strain grown on galactose.
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Analysis of cytotoxicity data of extracts from the National Cancer Institute's Active Repository by the COMPARE protocol was carried out using camptothecin as a reference point. Extracts identified by this process were further... more
Analysis of cytotoxicity data of extracts from the National Cancer Institute's Active Repository by the COMPARE protocol was carried out using camptothecin as a reference point. Extracts identified by this process were further characterized by a selective yeast bioassay for inhibitors of topoisomerase I and by a biochemical assay for compounds that stabilize the topoisomerase I-DNA covalent binary complex. Five of the extracts were positive in the yeast bioassay, and eight extracts showed activity on the assay that monitors stabilization of the topoisomerase I-DNA complex. Four of the latter extracts were inactive in the yeast bioassay, and thus would not have been identified as hits without the COMPARE preselection process. One of the extracts, from Pyrenacantha klaineana, was selected for detailed investigation, and fractionation of this extract yielded camptothecin and 9-methoxycamptothecin as the bioactive constituents.
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Our development of PDE10A inhibitors began with an HTS screening hit (1) that exhibited both high p-glycoprotein (P-gp) efflux ratios in rat and human and poor metabolic stability. On the basis of cocrystal structure of 1 in human PDE10A... more
Our development of PDE10A inhibitors began with an HTS screening hit (1) that exhibited both high p-glycoprotein (P-gp) efflux ratios in rat and human and poor metabolic stability. On the basis of cocrystal structure of 1 in human PDE10A enzyme, we designed a novel keto-benzimidazole 26 with comparable PDE10A potency devoid of efflux liabilities. On target in vivo coverage of PDE10A in rat brain was assessed using our previously reported LC-MS/MS receptor occupancy (RO) technology. Compound 26 achieved 55% RO of PDE10A at 30 mg/kg po and covered PDE10A receptors in rat brain in a dose-dependent manner. Cocrystal structure of 26 in PDE10A confirmed the binding mode of the novel scaffold. Further optimization resulted in the identification of keto-benzimidazole 34, which showed an increased in vivo efficacy of 57% RO in rats at 10 mg/kg po and an improved in vivo rat clearance and oral bioavailability.
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This report describes the development and validation of a robust robotic system that fully integrates all peripheral devices needed for the automated preparation of plasma samples by protein precipitation. The liquid handling system... more
This report describes the development and validation of a robust robotic system that fully integrates all peripheral devices needed for the automated preparation of plasma samples by protein precipitation. The liquid handling system consisted of a Tecan Freedom EVO 200 liquid handling platform equipped with an 8-channel liquid handling arm, two robotic plate-handling arms, and two plate shakers. Important additional components integrated into the platform were a robotic temperature-controlled centrifuge, a plate sealer, and a plate seal piercing station. These enabled unattended operation starting from a stock solution of the test compound, a set of test plasma samples and associated reagents. The stock solution of the test compound was used to prepare plasma calibration and quality control samples. Once calibration and quality control samples were prepared, precipitation of plasma proteins was achieved by addition of three volumes of acetonitrile. Integration of the peripheral devices allowed automated sequential completion of the centrifugation, plate sealing, piercing and supernatant transferral steps. The method produced a sealed, injection-ready 96-well plate of plasma extracts. Accuracy and precision of the automated system were satisfactory for the intended use: intra-day and the inter-day precision were excellent (C.V.<5%), while the intra-day and inter-day accuracies were acceptable (relative error<8%). The flexibility of the platform was sufficient to accommodate pharmacokinetic studies of different numbers of animals and time points. To the best of our knowledge, this represents the first complete automation of the protein precipitation method for plasma sample analysis.
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Taxus chinensis var. mairei (Taxaceae) is a domestic variety of yew species in local China. This plant is one of the sources for paclitaxel, which is a promising antineoplastic chemotherapy drugs during the last decade. We have sequenced... more
Taxus chinensis var. mairei (Taxaceae) is a domestic variety of yew species in local China. This plant is one of the sources for paclitaxel, which is a promising antineoplastic chemotherapy drugs during the last decade. We have sequenced the complete nucleotide sequence of the chloroplast (cp) genome of T. chinensis var. mairei. The T. chinensis var. mairei cp genome is 129,513 bp in length, with 113 single copy genes and two duplicated genes (trnI-CAU, trnQ-UUG). Among the 113 single copy genes, 9 are intron-containing. Compared to other land plant cp genomes, the T. chinensis var. mairei cp genome has lost one of the large inverted repeats (IRs) found in angiosperms, fern, liverwort, and gymnosperm such as Cycas revoluta and Ginkgo biloba L. Compared to related species, the gene order of T. chinensis var. mairei has a large inversion of ~110kb including 91 genes (from rps18 to accD) with gene contents unarranged. Repeat analysis identified 48 direct and 2 inverted repeats 30 bp long or longer with a sequence identity greater than 90%. Repeated short segments were found in genes rps18, rps19 and clpP. Analysis also revealed 22 simple sequence repeat (SSR) loci and almost all are composed of A or T.
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The expression of inducible nitric oxide synthase (iNOS) and the resultant increased nitric oxide production are associated with endotoxemia and atherosclerotic lesions observed in transplant hearts or balloon-injured artery.... more
The expression of inducible nitric oxide synthase (iNOS) and the resultant increased nitric oxide production are associated with endotoxemia and atherosclerotic lesions observed in transplant hearts or balloon-injured artery. Ursodeoxycholic acid has been shown to have cardiovascular protective effects, such as inhibition of the development of transplant arteriosclerosis, but its mechanism remains unclear. Here, we investigated the effects of ursodeoxycholic acid on nitric oxide production and the expression of iNOS in vascular smooth muscle cells isolated from adult rat aorta and rabbit coronary artery. Nitrite released from cells in the culture medium was measured with the Griess reaction. iNOS mRNA and protein were measured by Northern and Western blot analyses. Treatment with ursodeoxycholic acid (30-1000 microM) significantly inhibited lipopolysaccharide plus interferon-gamma-induced nitric oxide production in a concentration-dependent manner, but ursodeoxycholic acid showed only small inhibitory effects on nitric oxide production that had already been induced by lipopolysaccharide plus interferon-gamma. Ursodeoxycholic acid by itself did not affect basal nitric oxide production. Ursodeoxycholic acid also suppressed lipopolysaccharide plus interferon-gamma-induced expression of iNOS mRNA and protein. Ursodeoxycholic acid had the most potent inhibitory effect among various kinds of bile acids examined, i.e. chenodeoxycholic acid, deoxycholic acid, cholic acid and conjugated bile acids such as tauroursodeoxycholic acid. These results suggest that ursodeoxycholic acid inhibits the induction of iNOS and then nitric oxide production in aortic and coronary artery smooth muscle cells, suggesting a possible mechanism for the cardiovascular protective effect of ursodeoxycholic acid under various pathophysiological conditions such as endotoxemia and atherosclerosis.
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Research Interests: Cancer, Ubiquitin, Cell line, Humans, Mice, and 5 moreFemale, Animals, Cytoprotection, Middle Aged, and Imidazoles
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The optimization of a series of 8-aza-quinazolinone analogs for antagonist activity against the CXCR3 receptor is reported. Compounds were optimized to avoid the formation of active metabolites and time-dependent-inhibitors of CYP3A4. In... more
The optimization of a series of 8-aza-quinazolinone analogs for antagonist activity against the CXCR3 receptor is reported. Compounds were optimized to avoid the formation of active metabolites and time-dependent-inhibitors of CYP3A4. In addition, antagonists showed potent against CXCR3 activity in whole blood and optimized to avoid activity in the chromosomal aberration assay. Compound 25 was identified as having the optimal balance of CXCR3 activity and pharmacokinetic properties across multiple pre-clinical species, which are reported herein.
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In this communication, human 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitory activities of a novel series of diarylsulfones are described. Optimization of this series resulted in several highly potent 11β-HSD1 inhibitors... more
In this communication, human 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitory activities of a novel series of diarylsulfones are described. Optimization of this series resulted in several highly potent 11β-HSD1 inhibitors with excellent pharmacokinetic (PK) properties. Compound (S)-25 showed excellent efficacy in a non-human primate ex vivo pharmacodynamic model.
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A strain of yeast rendered repair deficient by the conditional expression of the RAD52 locus was used to search for natural products capable of damaging DNA. Four ellagic acid derivatives, namely... more
A strain of yeast rendered repair deficient by the conditional expression of the RAD52 locus was used to search for natural products capable of damaging DNA. Four ellagic acid derivatives, namely 3,3'-dimethyl-4'-O-beta-D-glucopyranosyl ellagic acid (1), 3,3',4-trimethyl-4'-O-beta-D-glucopyranosyl ellagic acid (2), 3'-methyl-3,4-O,O-methylidene ellagic acid (3) and 3'-methyl-3,4-O,O-methylidene-4'-O-beta-D-glucopyranosyl ellagic acid (4), were identified by this assay as DNA damaging natural principles from several plants, including Alangium javanicum, Anisophyllea apetala, Crypteronia paniculata, Mouririi sp. and Scholtzia parviflora. Although none of the isolated principles mediated frank strand scission of DNA in vitro, all of them potently inhibited the growth of yeast in the absence of expression of RAD52.
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We have performed a detailed characterization of the optical properties of a holographic polymer dispersed liquid crystal (LC) transmission grating with polymer scaffolding morphology, which was fabricated with conventional... more
We have performed a detailed characterization of the optical properties of a holographic polymer dispersed liquid crystal (LC) transmission grating with polymer scaffolding morphology, which was fabricated with conventional high-functionality acrylate monomer under low curing intensity. Temporal evolution of the grating formation was investigated, and the amount of phase-separated LC was determined by birefringence investigation. A grating model combined with anisotropic coupled-wave theory yielded good agreement with experimental data without any fitting parameter. The results in this study demonstrate the non droplet scaffolding morphology grating is characterized by a high degree of phase separation (70%), high anisotropy, low scattering loss (<6%), and high diffraction efficiency (95%).
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This paper investigates the monomer kinetics of polymer dispersed liquid crystal (PDLC) grating. Fourier transform infrared (FTIR) spectra are used in the studies of photoreaction kinetics. The results indicate that there is a relative... more
This paper investigates the monomer kinetics of polymer dispersed liquid crystal (PDLC) grating. Fourier transform infrared (FTIR) spectra are used in the studies of photoreaction kinetics. The results indicate that there is a relative stable stage arises after a very short initial stage. Based on FTIR studies, the monomer diffusion equation is deduced and necessary numerical simulations are carried out
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ABSTRACT Two types of display defects were found at special positions near the pixel indium tin oxide (ITO) edge in the multi-domain vertical alignment (MVA) mode liquid crystal display (LCD). Through simulated and experimental results,... more
ABSTRACT Two types of display defects were found at special positions near the pixel indium tin oxide (ITO) edge in the multi-domain vertical alignment (MVA) mode liquid crystal display (LCD). Through simulated and experimental results, the formation mechanisms of these two types of display defects, the detailed configurations of liquid crystal (LC) orientations at the display defect regions and the principle to suppress the defect dark line were analyzed and discussed. It was further found that the occurrence of the dark line was related to the positioning accuracy of substrate assembly. The reason of the dark line occurrence related with the positioning accuracy and the manufacturing margin were provided here.