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Find video protocols related to scientific articles indexed in Pubmed.
Fractional extreme value adaptive training method: fractional steepest descent approach.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 03-21-2015
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The application of fractional calculus to signal processing and adaptive learning is an emerging area of research. A novel fractional adaptive learning approach that utilizes fractional calculus is presented in this paper. In particular, a fractional steepest descent approach is proposed. A fractional quadratic energy norm is studied, and the stability and convergence of our proposed method are analyzed in detail. The fractional steepest descent approach is implemented numerically and its stability is analyzed experimentally.
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Total broadband transmission of microwaves through a subwavelength aperture by localized E-field coupling of split-ring resonators.
Opt Express
PUBLISHED: 11-18-2014
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Resonance coupling of two resonators with the same resonant frequency is a highly efficient energy transfer approach in physics. Here we report total broadband transmission of microwaves through a metallic subwavelength aperture using the coupled resonances of the strongly localized electric fields at the gaps of two split-ring resonators (SRRs) placed on either side of the aperture. At the center frequency of the broad band, the phase difference between the two localized time-varying electric fields is 90°, which is consistent with the critical coupling state that is a sufficient condition for the two-resonator system to realize total transmission if the resonators are assumed to be lossless.
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Effect of Crystallization of Cu2ZnSnSxSe4-x Counter Electrode on the Performance for Efficient Dye-Sensitized Solar Cells.
ACS Appl Mater Interfaces
PUBLISHED: 11-11-2014
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Cu2ZnSnSxSe4-x (CZTSSe) counter electrodes (CEs) in dye-sensitized solar cells (DSSCs) are commonly developed with porous structure, but their high surface area could also retard electron transport processes owing to the abundant grain boundaries. Herein, we employed a convenient solution method and a rapid heating process to prepare well crystalline CZTSSe CE in DSSCs. The influence of crystallization of CZTSSe film on DSSCs performances was discussed in depth. The thermogravimetric analysis, phase morphology, conductivity and electrochemical characteristics of CZTSSe films were performed. It is found that the rapid heating process is beneficial to the formation of well crystalline film with large-grain. As the porosity and grain boundaries in the bulk film are dramatically reduced with the enhanced crystallization, the charge transport process is gradually improved. Using cyclic voltammogram (CV) and electrochemical impedance spectroscopy (EIS) measurements, we propose that the accelerating charge transport is of great important to the photovoltaic performances of DSSCs due to their superior electrocatalytic activities. As the highest cell efficiency achieved, well crystalline CZTSSe is an efficient CE catalytic material.
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Cr(VI) Reduction and Cr(III) Immobilization by Acinetobacter sp. HK-1 with the Assistance of a Novel Quinone/Graphene Oxide Composite.
Environ. Sci. Technol.
PUBLISHED: 10-23-2014
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Cr(VI) biotreatment has attracted a substantial amount of interest due to its cost effectiveness and environmental friendliness. However, the slow Cr(VI) bioreduction rate and the formed organo-Cr(III) in solution are bottlenecks for biotechnology application. In this study, a novel strain, Acinetobacter sp. HK-1, capable of reducing Cr(VI) and immobilizing Cr(III) was isolated. Under optimal conditions, the Cr(VI) reduction rate could reach 3.82 mg h(-1) g cell(-1). To improve the Cr(VI) reduction rate, two quinone/graphene oxide composites (Q-GOs) were first prepared via a one-step covalent chemical reaction. The results showed that 2-amino-3-chloro-1,4-naphthoquinone-GO (NQ-GO) exhibited a better catalytic performance in Cr(VI) reduction compared to 2-aminoanthraquinone-GO. Specifically, in the presence of 50 mg L(-1) NQ-GO, a Cr(VI) removal rate of 190 mg h(-1) g cell(-1), which was the highest rate obtained, was achieved. The increased Cr(VI) reduction rate is mainly the result of NQ-GO significantly increasing the Cr(VI) reduction activity of cell membrane proteins containing dominant Cr(VI) reductases. X-ray photoelectron spectroscopy analysis found that Cr(VI) was reduced to insoluble Cr(III), which was immobilized by glycolipids secreted by strain HK-1. These findings indicate that the application of strain HK-1 and NQ-GO is a promising strategy for enhancing the treatment of Cr(VI)-containing wastewater.
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Study of light-absorbing crystal birefringence and electrical modulation mechanisms for coupled thermal-optical effects.
Appl Opt
PUBLISHED: 10-17-2014
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This paper discusses Gaussian laser transmission in double-refraction crystal whose incident light wavelength is within its absorption wave band. Two scenarios for coupled radiation and heat conduction are considered: one is provided with an applied external electric field, the other is not. A circular heat source with a Gaussian energy distribution is introduced to present the crystal's light-absorption process. The electromagnetic field frequency domain analysis equation and energy equation are solved to simulate the phenomenon by using the finite element method. It focuses on the influence of different values such as wavelength, incident light intensity, heat transfer coefficient, ambient temperature, crystal thickness, and applied electric field strength. The results show that the refraction index of polarized light increases with the increase of crystal temperature. It decreases as the strength of the applied electric field increases if it is positive. The mechanism of electrical modulation for the thermo-optical effect is used to keep the polarized light's index of refraction constant in our simulation. The quantitative relation between thermal boundary condition and strength of applied electric field during electrical modulation is determined. Numerical results indicate a possible approach to removing adverse thermal effects such as depolarization and wavefront distortion, which are caused by thermal deposition during linear laser absorption.
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An improved scheme for Flip-OFDM based on Hartley transform in short-range IM/DD systems.
Opt Express
PUBLISHED: 10-17-2014
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In this paper, an improved Flip-OFDM scheme is proposed for IM/DD optical systems, where the modulation/demodulation processing takes advantage of the fast Hartley transform (FHT) algorithm. We realize the improved scheme in one symbol period while conventional Flip-OFDM scheme based on fast Fourier transform (FFT) in two consecutive symbol periods. So the complexity of many operations in improved scheme is half of that in conventional scheme, such as CP operation, polarity inversion and symbol delay. Compared to FFT with complex input constellation, the complexity of FHT with real input constellation is halved. The transmission experiment over 50-km SSMF has been realized to verify the feasibility of improved scheme. In conclusion, the improved scheme has the same BER performance with conventional scheme, but great superiority on complexity.
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Sleep characteristics and psychological symptoms in patients with locally advanced nasopharyngeal carcinoma before and after intensity-modulated radiotherapy and concurrent chemotherapy.
Psychol Health Med
PUBLISHED: 10-10-2014
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Sleep disturbances and psychological distress are the most common adverse effects associated with cancer diagnosis and treatment. The aim of this study was to examine sleep and psychological characteristics in patients with local-advanced nasopharyngeal carcinoma (NPC) following completion of intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy, and to describe the predictors of post-test psychological symptoms after treatment. Sleep quality and psychological symptoms were measured using Pittsburgh sleep-quality index (PSQI) and symptom checklist-90 in 60 local-advanced NPC patients treated with IMRT and concurrent chemotherapy, respectively. After treatment, the subscores of subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction increased significantly compared with their pre-test scores. Similar results were observed for the mean PSQI global score. However, for psychological symptoms, only subscores of somatization and depression were higher than their baseline level. Multivariate analysis revealed that concurrent chemotherapy cycle was the only predictor of depression after treatment among all of the psychological symptoms assessed. These findings indicate that sleep disturbance and psychological distress are significant problems in NPC patients treated with IMRT and concurrent chemotherapy. Patients who receive many cycles of concurrent chemotherapy may be at an increased risk of depression after completion of IMRT.
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Evidence of recombinant strains of porcine epidemic diarrhea virus, United States, 2013.
Emerging Infect. Dis.
PUBLISHED: 10-02-2014
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To investigate the evolutionary process by which porcine epidemic diarrhea virus (PEDV) in the United States hypothetically descended from strains in China, we analyzed PEDV-positive samples collected in China during January 2012-July 2013. Recombination in 2 strain sublineages was likely associated with identification of PEDV in the United States in 2013.
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Efficacy and safety of carmustine wafers in the treatment of glioblastoma multiforme: a systematic review.
Turk Neurosurg
PUBLISHED: 10-01-2014
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The aim of this study was to a conduct a systematic review of carmustine wafers (Gliadel wafers) for the treatment of glioblastoma multiforme (GBM) to assess the survival benefit and safety of this therapy. The inclusion criteria were 1) prospective or retrospective clinical trial; 2) patients who had undergone resection for primary GBM or first recurrence of GBM with or without carmustine wafer implantation; 3) patients with malignant gliomas that included GBM; 4) outcomes including survival analysis of the GBM population. Six trials met the inclusion criteria; four were randomized, controlled trials and two were retrospective. The trials varied with regard to the type of patients and interventions. In three of the trials, patients with GBM who received carmustine wafers had significantly longer median survival than patients who did not receive wafers. Implantation of carmustine wafers did not significantly improve progression-free survival. Carmustine wafers did not increase adverse effects. This systematic review suggests that carmustine wafers have demonstrated promise as an effective and tolerable treatment in comparison to other treatment strategies in patients with GBM.
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Hydrogen-bond memory and water-skin supersolidity resolving the Mpemba paradox.
Phys Chem Chem Phys
PUBLISHED: 09-26-2014
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The Mpemba paradox, that is, hotter water freezes faster than colder water, has baffled thinkers like Francis Bacon, René Descartes, and Aristotle since B.C. 350. However, a commonly accepted understanding or theoretical reproduction of this effect remains challenging. Numerical reproduction of observations, shown herewith, confirms that water skin supersolidity [Zhang et al., Phys. Chem. Chem. Phys., DOI: ] enhances the local thermal diffusivity favoring heat flowing outwardly in the liquid path. Analysis of experimental database reveals that the hydrogen bond (O:H-O) possesses memory to emit energy at a rate depending on its initial storage. Unlike other usual materials that lengthen and soften all bonds when they absorb thermal energy, water performs abnormally under heating to lengthen the O:H nonbond and shorten the H-O covalent bond through inter-oxygen Coulomb coupling [Sun et al., J. Phys. Chem. Lett., 2013, 4, 3238]. Cooling does the opposite to release energy, like releasing a coupled pair of bungees, at a rate of history dependence. Being sensitive to the source volume, skin radiation, and the drain temperature, the Mpemba effect proceeds only in the strictly non-adiabatic 'source-path-drain' cycling system for the heat "emission-conduction-dissipation" dynamics with a relaxation time that drops exponentially with the rise of the initial temperature of the liquid source.
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Efficient Selective Catalytic Reduction of NO by Novel Carbon-doped Metal Catalysts Made from Electroplating Sludge.
Environ. Sci. Technol.
PUBLISHED: 09-26-2014
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Electroplating sludges, once regarded as industrial wastes, are precious resources of various transition metals. This research has thus investigated the recycling of an electroplating sludge as a novel carbon-doped metal (Fe, Ni, Mg, Cu, and Zn) catalyst, which was different from a traditional carbon-supported metal catalyst, for effective NO selective catalytic reduction (SCR). This catalyst removed >99.7% NO at a temperature as low as 300 °C. It also removed NO steadily (>99%) with a maximum specific accumulative reduced amount (MSARA) of 3.4 mmol/g. Gas species analyses showed that NO removal was accompanied by evolving N2 and CO2. Moreover, in a wide temperature window, the sludge catalyst showed a higher CO2 selectivity (>99%) than an activated carbon-supported metal catalyst. Structure characterizations revealed that carbon-doped metal was transformed to metal oxide in the sludge catalyst after the catalytic test, with most carbon (2.33 wt %) being consumed. These observations suggest that NO removal over the sludge catalyst is a typical SCR where metals/metal oxides act as the catalytic center and carbon as the reducing reagent. Therefore, our report probably provides an opportunity for high value-added utilizations of heavy-metal wastes in mitigating atmospheric pollutions.
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Magnetically tunable Mie resonance-based dielectric metamaterials.
Sci Rep
PUBLISHED: 09-14-2014
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Electromagnetic materials with tunable permeability and permittivity are highly desirable for wireless communication and radar technology. However, the tunability of electromagnetic parameters is an immense challenge for conventional materials and metamaterials. Here, we demonstrate a magnetically tunable Mie resonance-based dielectric metamaterials. The magnetically tunable property is derived from the coupling of the Mie resonance of dielectric cube and ferromagnetic precession of ferrite cuboid. Both the simulated and experimental results indicate that the effective permeability and permittivity of the metamaterial can be tuned by modifying the applied magnetic field. This mechanism offers a promising means of constructing microwave devices with large tunable ranges and considerable potential for tailoring via a metamaterial route.
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Phase-dependent photocatalytic H2 evolution of copper zinc tin sulfide under visible light.
Chem. Commun. (Camb.)
PUBLISHED: 09-11-2014
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CZTS exhibited apparently phase-dependent photocatalytic H2 evolution under visible light. Possible factors for the phase-dependent photocatalytic activity of CZTS were discussed in detail.
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A common supersolid skin covering both water and ice.
Phys Chem Chem Phys
PUBLISHED: 09-09-2014
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Consistency in experimental observations, numerical calculations, and theoretical predictions have revealed that the skins of water and ice share the same attribute of supersolidity characterized by an identical H-O vibration frequency of 3450 cm(-1). Molecular undercoordination and inter-electron-pair repulsion shortens the H-O bond and lengthens the O:H nonbond, leading to a dual process of nonbonding electron polarization. This relaxation-polarization process enhances the dipole moment, elasticity, viscosity, and thermal stability of these skins with a 25% density loss, which is responsible for the hydrophobicity and toughness of the water skin and results in the slippery behavior of ice.
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Detection of parent-of-origin effects for quantitative traits using general pedigree data.
J. Genet.
PUBLISHED: 09-06-2014
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Genomic imprinting is a genetic phenomenon in which certain alleles are differentially expressed in a parent-of-origin-specific manner, and plays an important role in the study of complex traits. For a diallelic marker locus in human, the parentalasymmetry tests Q-PAT(c) with any constant c were developed to detect parent-of-origin effects for quantitative traits. However, these methods can only be applied to deal with nuclear families and thus are not suitable for extended pedigrees. In this study, by making no assumption about the distribution of the quantitative trait, we first propose the pedigree parentalasymmetry tests Q-PPAT(c) with any constant c for quantitative traits to test for parent-of-origin effects based on nuclear families with complete information from general pedigree data, in the presence of association between marker alleles under study and quantitative traits. When there are any genotypes missing in pedigrees, we utilize Monte Carlo (MC) sampling and estimation and develop the Q-MCPPAT(c) statistics to test for parent-of-origin effects. Various simulation studies are conducted to assess the performance of the proposed methods, for different sample sizes, genotype missing rates, degrees of imprinting effects and population models. Simulation results show that the proposed methods control the size well under the null hypothesis of no parent-of-origin effects and Q-PPAT(c) are robust to population stratification. In addition, the power comparison demonstrates that Q-PPAT(c) and Q-MCPPAT(c) for pedigree data are much more powerful than Q-PAT(c) only using two-generation nuclear families selected from extended pedigrees.
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MiR-451 Suppresses Cell Proliferation and Metastasis in A549 Lung Cancer Cells.
Mol. Biotechnol.
PUBLISHED: 08-24-2014
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Recent study showed that inflammation was related to lung cancer. However, the exact cause of lung inflammation leading to carcinogenesis is unknown. MicroRNAs (miRNAs) are a group of endogenous non-coding small RNAs that regulate the activity of targeted mRNAs by inflammatory response in many diseases. MiR-451 was reported to relate to the development of lung cancer and metastasis of glioma. But the effect of miR-451 on cell proliferation, migration, and invasion of lung cancer is not really clear. In order to explore the molecular mechanism of the occurrence and development of lung cancer, we investigated the effect of human miR-451 on the proliferation, invasion, and metastasis in lung cancer cell line A549. The miR-451 expression construct was generated into pGenesil-1.1 and transfected into A549 cells. Results showed that the recombinant vectors were verified by sequencing. And miR-451 was over-expressed in A549 by real-time RT PCR. Furthermore, the proliferation, invasion, and metastasis of the cells in miR-451 group were inhibited significantly compared with those in control and A549 groups by MTT assay, Transwell invasion assay, and wound-healing assay. And the lung cancer metastasis factors (MMP-2, MMP-9, VEGF, and CXCR4) were decreased in miR-451 group by Western blot. Moreover, it was proved that inflammation-related gene-PSMB8 was a target for miR-451 by bioinformatics analysis and dual-luciferase reporter assay. And the protein expressions of PSMB8 and NOS2 were decreased in miR-451 group compared with those in control and A549 groups. Therefore, our findings indicated that miR-451 related to PSMB8/NOS2 inflammatory factors may suppress the development and migration of lung cancer, providing evidence for the role of miR-451 in lung cancer.
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How well have China's recent five-year plans been implemented for energy conservation and air pollution control?
Environ. Sci. Technol.
PUBLISHED: 08-21-2014
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This study evaluates how well China's 11th and 12th Five-Year Plans have been implemented in terms of energy conservation and air pollution control and deconstructs the effects of the economic, energy, and environmental policies included in the Plans. A "counterfactual" comparative-scenario method is deployed, which assumes a business as usual scenario in which the changes in economic, energy, and environmental parameters are "frozen", and then reactivates them one by one, with the help of LEAP modeling. It is found that during the 11th Five-Year Plan period, the binding targets were basically achieved. Economic growth put a great strain upon the energy demand and the environment, but energy policy made a decisive contribution by promoting energy efficiency and structure. Environmental policy promoted the deployment of end-of-pipe treatment which led to the control of certain air pollutants but at the expense of an increase in energy use and in the emission of other pollutants. During the ongoing 12th Five-Year Plan period, energy policy's potential for efficiency improvement is shrinking, but economic policy is restraining economic growth thus making a positive contribution. Environmental policy attempts to enforce multipollutant reduction, but there is still insufficient focus on the cocontrol of different pollutants and CO2.
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Neurotensin signaling regulates stem-like traits of glioblastoma stem cells through activation of IL-8/CXCR1/STAT3 pathway.
Cell. Signal.
PUBLISHED: 08-14-2014
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We recently found that neurotensin (NTS) and its primary receptor NTSR1 play a crucial role in glioblastoma cell proliferation and invasion. However, very little is known regarding the functional role of NTS/NTSR1 signaling in glioblastoma stem cells (GSCs). Here, we showed that NTSR1 is highly expressed in GSCs than its non-GSC counterparts. Pharmacological blockade with SR48692 or lentivirus mediated knockdown of NTSR1 efficiently reduced the sphere-forming ability and expression of stem cell markers such as nestin and Sox2 in GSCs isolated from glioblastoma cell line and glioblastoma tissues. Conversely, treated GSCs with NTS led to increase of tumor sphere formation. Mechanistically, we demonstrated that EGFR-dependent enhancement of IL-8 secretion is responsible for the effect of NTS signaling in the regulation of stem-like traits. Finally, we showed that NTSR1 or IL-8 knockdown decreased the phosphorylation of transcriptional factor STAT3 at Tyr705, which is a major transcription factor implicated in the regulation of GSC stem-like traits. Although both CXCR1 and CXCR2 inhibition reduced the tumor sphere formation, we found that CXCR1, but not CXCR2, is primarily responsible for STAT3 phosphorylation. Taken together, our findings suggest that NTS/IL-8/CXCR1/STAT3 signaling is crucial for the maintenance of stem-like traits in GSCs and provides a potential therapeutic target for glioblastoma therapy.
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Effects of rhynchophylline on GluN1 and GluN2B expressions in primary cultured hippocampal neurons.
Fitoterapia
PUBLISHED: 08-07-2014
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N-methyl-d-aspartate (NMDA) receptor subunits GluN1 and GluN2B in hippocampal neurons play key roles in anxiety. Our previous studies show that rhynchophylline, an active component of the Uncaria species, down-regulates GluN2B expression in the hippocampal CA1 area of amphetamine-induced rat. The effects of rhynchophylline on expressions of GluN1 and GluN2B in primary hippocampal neurons in neonatal rats in vitro were investigated. Neonatal hippocampal neurons were cultured with neurobasal-A medium. After incubation for 6h or 48 h with rhynchophylline (non-competitive NMDAR antagonist) and MK-801 (non-competitive NMDAR antagonist with anxiolytic effect, as the control drug) from day 6, neuron toxicity, mRNA and protein expressions of GluN1 and GluN2B were analyzed. GluN1 is mainly distributed on neuronal axons and dendritic trunks, cytoplasm and cell membrane near axons and dendrites. GluN2B is mainly distributed on the membrane, dendrites, and axon membranes. GluN1 and GluN2B are codistributed on dendritic trunks and dendritic spines. After 48 h incubation, a lower concentration of rhynchophylline (lower than 400 ?mol/L) and MK-801 (lower than 200 ?mol/L) have no toxicity on neonatal hippocampal neurons. Rhynchophylline up-regulated GluN1 mRNA expression at 6h and mRNA and protein expressions at 48h, but down-regulated GluN2B mRNA and protein expressions at 48 h. However, GluN1 and GluN2B mRNA expressions were down-regulated at 6h, and mRNA and protein expressions were both up-regulated by MK-801 at 48h. These findings show that rhynchophylline reciprocally regulates GluN1 and GluN2B expressions in hippocampal neurons, indicating a potential anxiolytic property for rhynchophylline.
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[Preparation of nanoparticles-modified silica monolith for on-column surface enhanced Raman spectroscopy].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 08-07-2014
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A novel silica monolith modified with Ag/Au nanoparticles was prepared for the on-column surface enhanced Raman spectroscopy (SERS). The bare monolithic silica column was prepared from in-situ co-condensation of tetraethoxysilane (TMOS) and methyl trimethoxysilane (MTMS) in the presence of polyethylene glycol (PEG) via a sol-gel process in the capillary, and was chemically modified with (3-mercaptopropyl) trimethoxysilane (MTPMS), followed by immobilization of Ag/Au nanoparticles. Transmission electron microscopy (TEM) and UV-Vis spectrometer were used to collect the TEM images and the extinction spectra of the nanoparticles colloid, respectively. Scanning electron microscope (SEM) was utilized to record the morphology of the silica monolith The authros used p-aminothiophenol (PATP) as a probing molecule, and the SERS effect was investigated on Au/Ag nanoparticle-modified silica monolith under the excitation line of 633 and 532 nm, respectively. It is concluded that nanoparticle-modified silica monoliths will have broad application to the on-site detection of food and water contaminants in the field.
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Expansion of genotypic diversity and establishment of 2009 H1N1 pandemic-origin internal genes in pigs in China.
J. Virol.
PUBLISHED: 07-09-2014
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Two-way transmission of influenza viruses between humans and swine has been frequently observed, and the occurrence of the 2009 H1N1 pandemic influenza virus (pdm/09) demonstrated that swine-origin viruses could facilitate the genesis of a pandemic strain. Although multiple introductions to and reassortment in swine of the pdm/09 virus have been repeatedly reported in both Eurasia and the Americas, its long-term impact on the development of swine influenza viruses (SIVs) has not been systematically explored. Our comprehensive evolutionary studies of the complete genomes of 387 SIVs obtained from 2009 to 2012 by influenza virus surveillance in China revealed 17 reassortant genotypes with pdm/09-origin genes. Even though the entire 2009 pandemic virus and its surface genes cannot persist, its internal genes have become established and are now the predominant lineages in pigs in the region. The main persistent pdm/09-origin reassortant forms had at least five pdm/09-origin internal genes, and their surface genes were primarily of European avian-like (EA) or human H3N2-like SIV origin. These findings represent a marked change in the evolutionary patterns and ecosystem of SIVs in China. It is possible that the pdm/09-origin internal genes are in the process of replacing EA or triple-reassortant-like internal genes. These alterations in the SIV gene pool need to be continually monitored to assess changes in the potential for SIV transmission to humans.
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Seroprevalence and Risk Factors of Chlamydia abortus Infection in Tibetan Sheep in Gansu Province, Northwest China.
ScientificWorldJournal
PUBLISHED: 06-27-2014
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Chlamydia abortus, an important pathogen in a variety of animals, is associated with abortion in sheep. In the present study, 1732 blood samples, collected from Tibetan sheep between June 2013 and April 2014, were examined by the indirect hemagglutination (IHA) test, aiming to evaluate the seroprevalence and risk factors of C. abortus infection in Tibetan sheep. 323 of 1732 (18.65%) samples were seropositive for C. abortus antibodies at the cut-off of 1?:?16. A multivariate logistic regression analysis was used to evaluate the risk factors associated with seroprevalence, which could provide foundation to prevent and control C. abortus infection in Tibetan sheep. Gender of Tibetan sheep was left out of the final model because it is not significant in the logistic regression analysis (P > 0.05). Region, season, and age were considered as major risk factors associated with C. abortus infection in Tibetan sheep. Our study revealed a widespread and high prevalence of C. abortus infection in Tibetan sheep in Gansu province, northwest China, with higher exposure risk in different seasons and ages and distinct geographical distribution.
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CCL11 as a potential diagnostic marker for asthma?
J Asthma
PUBLISHED: 05-13-2014
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Asthma is an inflammatory airway disease characterized by airway eosinophilia, in which CCL11 (eotaxin) plays a crucial role. The aim of study is to determine the elevation of CCL11 levels in bronchoalveolar lavage fluid (BALF), blood, exhaled breath condensate (EBC) and sputum in asthma patients and to identify which medium yields the most significant change in CCL11 level.
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CMEIAS JFrad: A Digital Computing Tool to Discriminate the Fractal Geometry of Landscape Architectures and Spatial Patterns of Individual Cells in Microbial Biofilms.
Microb. Ecol.
PUBLISHED: 05-08-2014
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Image analysis of fractal geometry can be used to gain deeper insights into complex ecophysiological patterns and processes occurring within natural microbial biofilm landscapes, including the scale-dependent heterogeneities of their spatial architecture, biomass, and cell-cell interactions, all driven by the colonization behavior of optimal spatial positioning of organisms to maximize their efficiency in utilization of allocated nutrient resources. Here, we introduce CMEIAS JFrad, a new computing technology that analyzes the fractal geometry of complex biofilm architectures in digital landscape images. The software uniquely features a data-mining opportunity based on a comprehensive collection of 11 different mathematical methods to compute fractal dimension that are implemented into a wizard design to maximize ease-of-use for semi-automatic analysis of single images or fully automatic analysis of multiple images in a batch process. As examples of application, quantitative analyses of fractal dimension were used to optimize the important variable settings of brightness threshold and minimum object size in order to discriminate the complex architecture of freshwater microbial biofilms at multiple spatial scales, and also to differentiate the spatial patterns of individual bacterial cells that influence their cooperative interactions, resource use, and apportionment in situ. Version 1.0 of JFrad is implemented into a software package containing the program files, user manual, and tutorial images that will be freely available at http://cme.msu.edu/cmeias/ . This improvement in computational image informatics will strengthen microscopy-based approaches to analyze the dynamic landscape ecology of microbial biofilm populations and communities in situ at spatial resolutions that range from single cells to microcolonies.
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Sonic hedgehog pathway contributes to gastric cancer cell growth and proliferation.
Biores Open Access
PUBLISHED: 05-08-2014
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The Sonic Hedgehog (Shh) signaling pathway is commonly activated in gastrointestinal cancer. However, our understanding of the Shh pathway in gastric cancer remains limited. Here we examined the effects of cyclopamine, a specific inhibitor of the Shh signaling pathway, on cell growth and proliferation in gastric primary cancer cells GAM-016 and the MKN-45 cell line. The results showed that the Shh signaling molecules SHH, PTCH, SMO, GLI1, and GLI2 were intact and activated in both types of cells. Furthermore, we observed that cyclopamine inhibited gastric cancer cell proliferation through cell cycle arrest and apoptosis. An in vivo study using NOD/SCID mouse xenografts demonstrated that cyclopamine significantly prevented tumor growth and development. Our study indicated that Shh signaling pathway could promote gastric cancer cell proliferation and tumor development, and blocking this pathway may be a potential strategy in gastric cancer treatment.
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HIF-1? genetic variants and protein expression confer the susceptibility and prognosis of gliomas.
Neuromolecular Med.
PUBLISHED: 04-26-2014
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To investigate the role of HIF-1? genetic polymorphism of c.1772C>T and c.1790G>A in the incidence and prognosis of gliomas in a Chinese cohort, a total of 387 gliomas patients and 437 age- and sex-matched healthy controls were recruited. The genetic polymorphism of c.1772C>T and c.1790G>A was determined. We found that the genotype distribution at c.1772C>T showed significant difference between patients and controls. Multivariable analyses showed a significantly higher risk for gliomas in 1772TT genotype carriers (odds ratio 2.68, with CC as reference). In addition, we also found a significantly higher risk for grade III + IV gliomas was observed in 1772TT genotype carriers (odds ratio 2.21, with CC as reference). The overall survival rates in patients with 1772TT or 1772CT genotype were markedly lower compared with patients with CC (both P < 0.01). Our in vitro studies revealed that HIF-1? regulates the proliferation, migration and invasion of human glioma U251 cells. This study suggests that the c.1772C>T polymorphisms may be used as a molecular marker for gliomas occurrence, grades and clinical outcome in gliomas patients.
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A long noncoding RNA Sox2ot regulates lung cancer cell proliferation and is a prognostic indicator of poor survival.
Int. J. Biochem. Cell Biol.
PUBLISHED: 04-19-2014
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Sox2 overlapping transcript (Sox2ot) is a long noncoding RNA (lncRNA), localized on human chromosome 3q26.33, which is frequently amplified in lung squamous cell carcinomas (SCCs). However, its roles in lung cancer remain under investigation. In this study, we found that Sox2ot was up-regulated over two folds in 53.01% of human primary lung cancers (44/83). The expression level of Sox2ot is significantly higher in SCCs than that in adenocarcinomas (ADCs) of the lung. Further study found high Sox2ot expression predicted poor survival in lung cancer patients (P=0.0053), implying Sox2ot is a novel prognostic factor. In two human lung cancer cell lines, HCC827 and SK-MES-1, knocking down Sox2ot inhibited cell proliferation by inducing G2/M arrest, with a concomitant decrease of cells in S phase. Reduced protein levels of Cyclin B1 and Cdc2 were also observed. Importantly, knocking down Sox2ot decreased EZH2 expression and reintroduction of EZH2 allowed Sox2ot knockdown cells progressed through G2/M phase, which correlates with the restoration of Cyclin B1 and Cdc2 expressions. Altogether, our data suggested that Sox2ot plays an important role in regulating lung cancer cell proliferation, and may represent a novel prognostic indicator for the disease.
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Quick and efficient co-treatment of Zn(2+)/Ni(2+) and CN(-) via the formation of Ni(CN)4(2-) intercalated larger ZnAl-LDH crystals.
J. Hazard. Mater.
PUBLISHED: 04-16-2014
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The wide use of metal electroplating involving CN(-) necessitates the cost-effective treatment of both CN and metals (Zn, Cu, Ni etc.). In this research, we developed a novel strategy - Ni(2+)-assisted layered double hydroxide (LDH) precipitation - to simultaneously remove aqueous CN and Zn/Ni metals. The strategy is to convert CN(-)/Zn(CN)4(2-) to Ni(CN)4(2-) first, and then to quickly precipitate Ni(CN)4(2-)/CN(-) into LDH crystals. The conversion has been clearly evidenced by the change of CN characteristic FTIR bands of Zn-CN solution before and after adding Ni(NO3)2. The intercalation and efficient removal of CN have also been confirmed through the formation of LDH crystals XRD and SEM. In particular, a set of optimized experimental factors has been obtained by investigating their effects on CN removal efficiency in the simulated tests. Remarkably, over 95% CN were removed with high removal efficiencies of metals. Our results thus suggest that the current strategy is a quick, efficient and promising way to simultaneously treat both Ni and metals/CN rich electroplating wastewaters.
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Accelerating effect of bio-reduced graphene oxide on decolorization of Acid Red 18 by Shewanella algae.
Appl. Biochem. Biotechnol.
PUBLISHED: 04-09-2014
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In this study, the effects of bio-reduced graphene oxide (BRGO) on the bio-reduction of Acid Red 18 (AR 18) by Shewanella algae were first investigated, and a possible mechanism of BRGO-mediated AR 18 bio-decolorization was proposed. The prepared BRGO was characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffractometer (XRD), infrared spectroscopy (IR), Raman spectra, and transmission electron microscope (TEM), respectively. Moreover, electrochemical experiment demonstrated that BRGO is of good electrical conductivity. AR 18 bio-decolorization could be enhanced in dose-dependent manner of BRGO. The maximum increase in AR 18 removal efficiency was observed at a dose of 0.075 g L(-1) BRGO. Under the same conditions, BRGO could also improve the decolorization rates of Acid Red 88, Acid Red 27, and Acid Red 73. During decolorization, the formation of BRGO and cells composite was observed, which is beneficial for transferring electrons from cells to BRGO. In addition, BRGO could accelerate the bio-decolorization of AR 18 under saline conditions (2-7 %). These findings indicate that BRGO can accelerate the electrons transfer from cells to azo dyes.
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Overexpression of HP1? is associated with poor prognosis in non-small cell lung cancer cell through promoting cell survival.
Tumour Biol.
PUBLISHED: 04-06-2014
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Heterochromatin protein 1? (HP1?), which binds to di- or trimethylated lysine 9 on histone H3 (H3K9), plays an important role in chromatin packaging and gene transcriptional regulation. Recently, HP1? has been implicated in cancer development. However, its clinical relevance and functional role in non-small cell lung cancer (NSCLC) remain elusive. In this study, we found that HP1? expression was elevated in NSCLC samples at the messenger RNA (mRNA) level compared to adjacent normal lung tissues. In a cohort of 108 NSCLC patients, HP1? overexpression is significantly associated with N stage (P?=?0.003), pathological tumor-node-metastasis (TNM) stage (P?=?0.013), smoking status (P?=?0.009), and gender (P?=?0.042). Patients with a high level of HP1? expression showed a poorer overall survival rate than those with low HP1? expression (P?=?0.017). Multivariate analysis revealed that HP1? expression is an independent prognostic marker. We also found knockdown of HP1? in A549 and NCI-H1975 cells induced apoptosis accompanied with suppressed cell proliferation and colony formation. Consistently, pro-apoptotic proteins, Bax and GADD45?, were upregulated in response to HP1? depletion. Altogether, our data suggested that HP1? plays an important role in promoting NSCLC and may represent a novel prognostic biomarker and therapeutic target for the disease.
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High-throughput imaging of plant immune responses.
Methods Mol. Biol.
PUBLISHED: 03-20-2014
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Fluorescence confocal microscopy has emerged in the past decade as an important method for studying the cellular changes associated with plant-microbe interactions. One such change is the internalization into endosomes of the cell surface receptor FLAGELLIN SENSING 2 (FLS2) upon activation by its ligand, bacterial flagellin (flg22). Quantification of endosomes containing FLS2 can thus be used as a direct readout of immune response activation at the cellular level. High-throughput imaging of cellular events is routinely applied in chemical screening for pharmaceutical drug discovery, and we have adapted this system for quantification of plant leaf cellular parameters. In this chapter we describe the instrument setup for high-throughput imaging of leaves, protocols for flg22-induced endocytosis, image acquisition for fluorescent-tagged FLS2 receptors and subcellular markers, automated image analysis of cellular parameters, and data outputs of FLS2 endocytosis.
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Microwave memristive-like nonlinearity in a dielectric metamaterial.
Sci Rep
PUBLISHED: 03-19-2014
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Memristor exhibit interesting and valuable circuit properties and have thus become the subject of increasing scientific interest. Scientists wonder if they can conceive a microwave memristor that behaves as a memristor operating with electromagnetic fields. Here, we report a microwave memristive-like nonlinear phenomenon at room temperature in dielectric metamaterials consisting of CaTiO3-ZrO2 ceramic dielectric cubes. Hysteretic transmission-incident field power loops (similar to the hysteretic I-V loop of memristor which is the fingerprint of memristor) with various characteristics were systematically observed in the metamaterials, which exhibited designable microwave memristive-like behavior. The effect is attributed to the decreasing permittivity of the dielectric cubes with the increasing temperature generated by the interaction between the electromagnetic waves and the dielectric cubes. This work demonstrates the feasibility of fabrication transient photonic memristor at microwave frequencies with metamaterials.
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Cognitive function, mood, and sleep quality in patients treated with intensity-modulated radiation therapy for nasopharyngeal cancer: a prospective study.
Psychooncology
PUBLISHED: 03-13-2014
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The aim of this study was to prospectively evaluate the cognitive function, depression, anxiety, and sleep quality in patients with nasopharyngeal cancer (NPC) before and after intensity-modulated radiotherapy (IMRT).
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Anisotropic terahertz dielectric responses of sodium nitrate crystals.
Phys Chem Chem Phys
PUBLISHED: 03-05-2014
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Terahertz (THz) spectroscopy has become an effective tool to characterize the low-frequency rotational and vibrational modes of molecules. In addition, novel THz dielectric responses and optical properties on the basis of molecular rotation and vibration have attracted lots of attention because of their potential application in THz devices. In this paper, the dielectric response of low-symmetric sodium nitrate crystals in the frequency range of 0.2-1.5 THz was experimentally demonstrated. Four absorption bands at 0.23, 0.47, 0.92, and 1.15 THz were observed in the dielectric spectra and were tentatively ascribed to the rotational motion of nitrate ions. Based on the molecular rotation mechanism, the dielectric anisotropy and dielectric resonance of the crystal were discussed in detail.
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Steroid receptor coactivator-3 regulates glucose metabolism in bladder cancer cells through coactivation of hypoxia inducible factor 1?.
J. Biol. Chem.
PUBLISHED: 02-28-2014
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Cancer cell proliferation is a metabolically demanding process, requiring high glycolysis, which is known as "Warburg effect," to support anabolic growth. Steroid receptor coactivator-3 (SRC-3), a steroid receptor coactivator, is overexpressed and/or amplified in multiple cancer types, including non-steroid targeted cancers, such as urinary bladder cancer (UBC). However, whether SRC-3 regulates the metabolic reprogramming for cancer cell growth is unknown. Here, we reported that overexpression of SRC-3 accelerated UBC cell growth, accompanied by the increased expression of genes involved in glycolysis. Knockdown of SRC-3 reduced the UBC cell glycolytic rate under hypoxia, decreased tumor growth in nude mice, with reduction of proliferating cell nuclear antigen and lactate dehydrogenase expression levels. We further revealed that SRC-3 could interact with hypoxia inducible factor 1? (HIF1?), which is a key transcription factor required for glycolysis, and coactivate its transcriptional activity. SRC-3 was recruited to the promoters of HIF1?-target genes, such as glut1 and pgk1. The positive correlation of expression levels between SRC-3 and Glut1 proteins was demonstrated in human UBC patient samples. Inhibition of glycolysis through targeting HK2 or LDHA decelerated SRC-3 overexpression-induced cell growth. In summary, overexpression of SRC-3 promoted glycolysis in bladder cancer cells through HIF1? to facilitate tumorigenesis, which may be an intriguing drug target for bladder cancer therapy.
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Simultaneous determination of four bioactive flavonoids from Polygonum orientale L. in dog plasma by UPLC-ESI-MS/MS and application of the technique to pharmacokinetic studies.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 02-16-2014
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The in vivo effects of traditional herbal medicines are generally mediated by multiple bioactive components. The main constituents of Polygonum orientale L. are flavonoids such as orientin, vitexin, cynaroside, and quercitrin. The aim of this study was to develop and validate a method for characterizing these flavonoids, in order to better understand the pharmacokinetics and pharmacodynamics of P. orientale L. We used ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) to analyze the flavonoids. After precipitation of the proteins with methanol, the flavonoids were separated on a BEH C18 column (50mm×2.1mm, i.d., 1.7?m) by using an elution gradient of acetonitrile. Flavonoid content was determined using the multiple reaction monitoring (MRM) mode at m/z 449.2?329.2 for orientin, m/z 433.2?313.0 for vitexin, m/z 449.2?287.1 for cynaroside, m/z 449.2?303.4 for quercitrin, and m/z 417.0?267.0 for the internal standard, puerarin. Pharmacokinetics was assessed after intravenous administration of P. orientale L. extracts (POE) in Beagle dogs at a dose of 22, 44, or 88mg/kg. Analysis of the standard curves by linear regression revealed high linearity over a 243-fold dynamic range for the four flavonoids (the lower limit of quantitation values were 4-21ng/mL). The relative standard deviations of intra- and inter-day measurements were less than 15.1%, and the method was accurate to within -8.7% to 7.2%; the extraction recoveries from dog plasma were 70.6-89.3%, 69.8-88.7%, 72.5-85.7%, and 71.0-79.1% for orientin, vitexin, cynaroside, and quercitrin, respectively. Our results suggest non-linear pharmacokinetic characteristics with rapid clearance of the flavonoids. In conclusion, UPLC-ESI-MS/MS is a rapid and sensitive method for simultaneous quantification of multiple flavonoids from POE in dog plasma and is suitable for pharmacokinetic studies of herbal medicines.
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Prognostic significance of Tet methylcytosine dioxygenase 2 (TET2) gene mutations in adult patients with acute myeloid leukemia: a meta-analysis.
Leuk. Lymphoma
PUBLISHED: 02-15-2014
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Tet methylcytosine dioxygenase 2 (TET2) gene mutations have recently been recognized in acute myeloid leukemia (AML). We performed a meta-analysis to evaluate the controversial prognostic significance of TET2 mutations in AML. Eight studies, covering 2552 patients with AML, were included in this analysis. Pooled hazard ratios (HRs) indicated that TET2 mutations had a poor prognostic impact on the survival of patients with AML. The combined HR for overall survival (OS) was 1.53 and the summary HR for event-free survival (EFS) was 1.64. Additionally, TET2 mutations appeared to be an adverse prognostic indicator in both patients with cytogenetically normal (CN)-AML (HR for OS: 1.43 and HR for EFS: 1.76) and subgroups of patients with favorable-risk genotypes (HR for EFS: 2.35) and intermediate-I-risk genotypes (HR for EFS: 1.57). These findings indicate that TET2 mutations have an adverse impact on prognosis and may help to justify risk-adapted therapeutic strategies for patients with AML.
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Negative and near zero refraction metamaterials based on permanent magnetic ferrites.
Sci Rep
PUBLISHED: 01-29-2014
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Ferrite metamaterials based on the negative permeability of ferromagnetic resonance in ferrites are of great interest. However, such metamaterials face a limitation that the ferromagnetic resonance can only take place while an external magnetic field applied. Here, we demonstrate a metamaterial based on permanent magnetic ferrite which exhibits not only negative refraction but also near zero refraction without applied magnetic field. The wedge-shaped and slab-shaped structures of permanent magnetic ferrite-based metamaterials were prepared and the refraction properties were measured in a near-field scanning system. The negative and near zero refractive behaviors are confirmed by the measured spatial electric field maps. This work offers new opportunities for the development of ferrite-based metamaterials.
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The proteasome activator PA28?, a negative regulator of p53, is transcriptionally up-regulated by p53.
Int J Mol Sci
PUBLISHED: 01-23-2014
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PA28? (also called REG?, 11S? or PSME3) negatively regulates p53 activity by promoting its nuclear export and/or degradation. Here, using the RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) method, we identified the transcription start site of the PA28? gene. Assessment with the luciferase assay demonstrated that the sequence -193 to +16 is the basal promoter. Three p53 binding sites were found within the PA28? promoter utilizing a bioinformatics approach and were confirmed by chromatin immunoprecipitation and biotinylated DNA affinity precipitation experiments. The p53 protein promotes PA28? transcription, and p53-stimulated transcription of PA28? can be inhibited by PA28? itself. Our results suggest that PA28? and p53 form a negative feedback loop, which maintains the balance of p53 and PA28? in cells.
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A novel blind separation method in magnetic resonance images.
Comput Math Methods Med
PUBLISHED: 01-17-2014
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A novel global search algorithm based method is proposed to separate MR images blindly in this paper. The key point of the method is the formulation of the new matrix which forms a generalized permutation of the original mixing matrix. Since the lowest entropy is closely associated with the smooth degree of source images, blind image separation can be formulated to an entropy minimization problem by using the property that most of neighbor pixels are smooth. A new dataset can be obtained by multiplying the mixed matrix by the inverse of the new matrix. Thus, the search technique is used to searching for the lowest entropy values of the new data. Accordingly, the separation weight vector associated with the lowest entropy values can be obtained. Compared with the conventional independent component analysis (ICA), the original signals in the proposed algorithm are not required to be independent. Simulation results on MR images are employed to further show the advantages of the proposed method.
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Molecular rotation-vibration dynamics of low-symmetric hydrate crystal in the terahertz region.
J Phys Chem A
PUBLISHED: 01-03-2014
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The rotational and vibrational dynamics of molecules in copper sulfate pentahydrate crystal are investigated with terahertz dielectric spectra. It is shown that the relaxation-like dielectric dispersion in the low frequency region is related to the reorientation of water molecules under the driving of terahertz electric field, whereas the resonant dispersion can be ascribed to lattice vibration. It is also found that, due to the hydrogen-bond effect, the vibrational mode at about 1.83 THz along [-111] direction softens with decreasing temperature, that is, the crystal expands in this direction when cooled. On the contrary, the mode hardens in the direction perpendicular to [-111] during the cooling process. This contributes to the further understanding of the molecular structure and bonding features of hydrate crystals.
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Cu2ZnSnSe4 nanocrystals capped with S(2-) by ligand exchange: utilizing energy level alignment for efficiently reducing carrier rec ombination.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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In this work, we employed a convenient one-step synthesis method for synthesizing Cu2ZnSnSe4 (CZTSe) nanocrystals (NCs) in an excess selenium environment. This excess selenium situation enhanced the reaction of metal acetylacetonates with selenium, resulting in the burst nucleation of NCs at relatively low temperatures. The phase morphology and surface and optoelectronic properties of NCs before and after ligand exchange were discussed in depth. It was found that pure tetragonal-phase structure CZTSe NCs with approximately 1.7-eV bandgap could be synthesized. The removal of large organic molecules on CZTSe NCs after ligand exchange by S(2-) decreased the resistivity. The bandgap of the films after ligand exchange by 550°C selenization was also decreased due to better crystallinity. For potential application in CZTSe solar cells, we constructed an energy level diagram to explain the mutual effect between the absorption layer and CdS layer. Using cyclic voltammetry (CV) measurement, we found that the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of CZTSe films shifted down after ligand exchange. After energy level alignment at the CdS/CZTSe interface, a type I band alignment structure was more conveniently formed after ligand exchange. This structure acted as the barrier against injection electrons from ZnO to the CZTSe layer, and recombination would subsequently be depressed.
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Bioaccumulation of Cry1Ab protein from an herbivore reduces anti-oxidant enzyme activities in two spider species.
PLoS ONE
PUBLISHED: 01-01-2014
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Cry proteins are expressed in rice lines for lepidopteran pest control. These proteins can be transferred from transgenic rice plants to non-target arthropods, including planthoppers and then to a predatory spider. Movement of Cry proteins through food webs may reduce fitness of non-target arthropods, although recent publications indicated no serious changes in non-target populations. Nonetheless, Cry protein intoxication influences gene expression in Cry-sensitive insects. We posed the hypothesis that Cry protein intoxication influences enzyme activities in spiders acting in tri-trophic food webs. Here we report on the outcomes of experiments designed to test our hypothesis with two spider species. We demonstrated that the movement of CryAb protein from Drosophila culture medium into fruit flies maintained on the CryAb containing medium and from the flies to the spiders Ummeliata insecticeps and Pardosa pseudoannulata. We also show that the activities of three key metabolic enzymes, acetylcholine esterase (AchE), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) were significantly influenced in the spiders after feeding on Cry1Ab-containing fruit flies. We infer from these data that Cry proteins originating in transgenic crops impacts non-target arthropods at the physiological and biochemical levels, which may be one mechanism of Cry protein-related reductions in fitness of non-target beneficial predators.
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Decomposition of Potent Greenhouse Gas Sulfur Hexafluoride (SF6) by Kirschsteinite-dominant Stainless Steel Slag.
Environ. Sci. Technol.
PUBLISHED: 12-20-2013
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In this investigation, kirschsteinite-dominant stainless steel slag (SSS) has been found to decompose sulfur hexafluoride (SF6) with the activity higher than pure metal oxides, such as Fe2O3 and CaO. SSS is mainly made up of CaO·FeO·SiO2(CFS)/MgO·FeO·MnO(RO) phase conglomeration. The SF6 decomposition reaction with SSS at 500-700 °C generated solid MF2/MF3 and gaseous SiF4, SO2/SO3 as well as HF. When 10 wt % of SSS was replaced by Fe2O3 or CaO, the SF6 decomposition amount decreased from 21.0 to 15.2 or 15.0 mg/g at 600 °C. The advantage of SSS over Fe2O3 or CaO in the SF6 decomposition is related to its own special microstructure and composition. The dispersion of each oxide component in SSS reduces the sintering of freshly formed MF2/MF3, which is severe in the case of pure metal oxides and inhibits the continuous reaction of inner components. Moreover, SiO2 in SSS reacts with SF6 and evolves as gaseous SiF4, which leaves SSS with voids and consequently exposes inner oxides for further reactions. In addition, we have found that oxygen significantly inhibited the SF6 decomposition with SSS while H2O did not, which could be explained in terms of reaction pathways. This research thus demonstrates that waste material SSS could be potentially an effective removal reagent of greenhouse gas SF6.
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Multi-resolution-test for consistent phenotype discrimination and biomarker discovery in translational bioinformatics.
J Bioinform Comput Biol
PUBLISHED: 12-11-2013
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While high-throughput technologies are expected to play a critical role in clinical translational research for complex disease diagnosis, the ability to accurately and consistently discriminate disease phenotypes by determining the gene and protein expression patterns as signatures of different clinical conditions remains a challenge in translational bioinformatics. In this study, we propose a novel feature selection algorithm: Multi-Resolution-Test (MRT-test) that can produce significantly accurate and consistent phenotype discrimination across a series of omics data. Our algorithm can capture those features contributing to subtle data behaviors instead of selecting the features contributing to global data behaviors, which seems to be essential in achieving clinical level diagnosis for different expression data. Furthermore, as an effective biomarker discovery algorithm, it can achieve linear separation for high-dimensional omics data with few biomarkers. We apply our MRT-test to complex disease phenotype diagnosis by combining it with state-of-the-art classifiers and attain exceptional diagnostic results, which suggests that our methods advantage in molecular diagnostics. Experimental evaluation showed that MRT-test based diagnosis is able to generate consistent and robust clinical-level phenotype separation for various diseases. In addition, based on the seed biomarkers detected by the MRT-test, we design a novel network marker synthesis (NMS) algorithm to decipher the underlying molecular mechanisms of tumorigenesis from a systems viewpoint. Unlike existing top-down gene network building approaches, our network marker synthesis method has a less dependence on the global network and enables it to capture the gene regulators for different subnetwork markers, which will provide biologically meaningful insights for understanding the genetic basis of complex diseases.
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Three new ursane-type triterpenoids from the aerial parts of Isodon excisoides.
J Asian Nat Prod Res
PUBLISHED: 10-24-2013
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Three new ursane-type triterpenoids, 2?,3?-dihydroxy-11?,12?-epoxy-urs-28,13?-olide (1), 2?,3?,24-trihydroxy-11?,12?-epoxy-urs-28,13?-olide (2), and 2?,3?,24-trihydroxy-11,20(30)-dien-urs-28,13?-olide (6), together with six known ursane-type triterpenoids (3-5, 7-9), were isolated from the EtOAc extract of the aerial parts of Isodon excisoides. Their structures were elucidated on the basis of 1D NMR and 2D NMR analyses as well as HRMS experiments.
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The Residual Tumor Autophagy Marker LC3B Serves as a Prognostic Marker in Local Advanced Breast Cancer after Neoadjuvant Chemotherapy.
Clin. Cancer Res.
PUBLISHED: 10-18-2013
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This study sought to investigate the prognostic value of the autophagy marker microtubule-associated protein chain 3B (LC3B) in patients with residual tumors after neoadjuvant chemotherapy (NCT) for locally advanced breast cancer (LABC). Patients and Methods: The expression of LC3B in residual breast cancer cells was assessed by immunohistochemistry in surgical specimens from 229 patients diagnosed with histologically proven invasive breast cancer. All patients underwent NCT followed by mastectomy and were considered nonpathologic complete responders (non-pCR) after a pathologic evaluation. The prognostic value of various clinicopathologic factors was evaluated.
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Co-control of Local Air Pollutants and CO2 in the Chinese Iron and Steel Industry.
Environ. Sci. Technol.
PUBLISHED: 10-18-2013
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The present study proposes an integrated multipollutant cocontrol strategy framework in the context of the Chinese iron and steel industry. The unit cost of pollutant reduction (UCPR) was used to examine the cost-effectiveness of each emission reduction measure. The marginal abatement cost (MAC) curves for SO2, NOx, PM2.5, and CO2 were drawn based on the UCPR and the abatement potential. Air pollutant equivalence (APeq) captures the nature of the damage value-weights of various air pollutants and acts as uniformization multiple air pollutants index. Single pollutant abatement routes designed in accordance with the corresponding reduction targets revealed that the cocontrol strategy has promising potential. Moreover, with the same reduction cost limitations as the single pollutant abatement routes, the multipollutant cocontrol routes are able to obtain more desirable pollution reduction and health benefits. Co-control strategy generally shows cost-effective advantage over single-pollutant abatement strategy. The results are robust to changing parameters according to sensitivity analysis. Co-control strategy would be an important step to achieve energy/carbon intensity targets and pollution control targets in China. Though cocontrol strategy has got some traction in policy debates, there are barriers to integrate it into policy making in the near future in China.
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Polarization and incidence insensitive dielectric electromagnetically induced transparency metamaterial.
Opt Express
PUBLISHED: 10-10-2013
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In this manuscript, we demonstrate numerically classical analogy of electromagnetically induced transparency (EIT) with a windmill type metamaterial consisting of two dumbbell dielectric resonator. With proper external excitation, dielectric resonators serve as EIT bright and dark elements via electric and magnetic Mie resonances, respectively. Rigorous numerical analyses reveal that dielectric metamaterial exhibits sharp transparency peak characterized by large group index due to the destructive interference between EIT bright and dark resonators. Furthermore, such EIT transmission behavior keeps stable property with respect to polarization and incidence angles.
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Wurtzite copper-zinc-tin sulfide as a superior counter electrode material for dye-sensitized solar cells.
Nanoscale Res Lett
PUBLISHED: 09-27-2013
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Wurtzite and kesterite Cu2ZnSnS4 (CZTS) nanocrystals were employed as counter electrode (CE) materials for dye-sensitized solar cells (DSSCs). Compared to kesterite CZTS, the wurtzite CZTS exhibited higher electrocatalytic activity for catalyzing reduction of iodide electrolyte and better conductivity. Accordingly, the DSSC with wurtzite CZTS CE generated higher power conversion efficiency (6.89%) than that of Pt (6.23%) and kesterite CZTS (4.89%) CEs.
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Size, separation, structural order, and mass density of molecules packing in water and ice.
Sci Rep
PUBLISHED: 09-06-2013
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The structural symmetry and molecular separation in water and ice remain uncertain. We present herewith a solution to unifying the density, the structure order and symmetry, the size (H-O length dH), and the separation (d(OO) = d(L) + d(H) or the O:H length d(L)) of molecules packing in water and ice in terms of statistic mean. This solution reconciles: i) the d(L) and the d(H) symmetrization of the O:H-O bond in compressed ice, ii) the d(OO) relaxation of cooling water and ice and, iii) the d(OO) expansion of a dimer and between molecules at water surface. With any one of the d(OO), the density ?(g·cm?³), the d(L), and the d(H), as a known input, one can resolve the rest quantities using this solution that is probing conditions or methods independent. We clarified that: i) liquid water prefers statistically the mono-phase of tetrahedrally-coordinated structure with fluctuation, ii) the low-density phase (supersolid phase as it is strongly polarized with even lower density) exists only in regions consisting molecules with fewer than four neighbors and, iii) repulsion between electron pairs on adjacent oxygen atoms dictates the cooperative relaxation of the segmented O:H-O bond, which is responsible for the performance of water and ice.
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Robust joint analysis with data fusion in two-stage quantitative trait genome-wide association studies.
Comput Math Methods Med
PUBLISHED: 07-06-2013
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Genome-wide association studies (GWASs) in identifying the disease-associated genetic variants have been proved to be a great pioneering work. Two-stage design and analysis are often adopted in GWASs. Considering the genetic model uncertainty, many robust procedures have been proposed and applied in GWASs. However, the existing approaches mostly focused on binary traits, and few work has been done on continuous (quantitative) traits, since the statistical significance of these robust tests is difficult to calculate. In this paper, we develop a powerful F-statistic-based robust joint analysis method for quantitative traits using the combined raw data from both stages in the framework of two-staged GWASs. Explicit expressions are obtained to calculate the statistical significance and power. We show using simulations that the proposed method is substantially more robust than the F-test based on the additive model when the underlying genetic model is unknown. An example for rheumatic arthritis (RA) is used for illustration.
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Efficient removal of sulfur hexafluoride (SF6) through reacting with recycled electroplating sludge.
Environ. Sci. Technol.
PUBLISHED: 06-06-2013
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This paper reports that recycled electroplating sludge is able to efficiently remove greenhouse gas sulfur hexafluoride (SF6). The removal process involves various reactions of SF6 with the recycled sludge. Remarkably, the sludge completely removed SF6 at a capacity of 1.10 mmol/g (SF6/sludge) at 600 °C. More importantly, the evolved gases were SO2, SiF4, and a limited amount of HF, with no toxic SOF4, SO2F2, or SF4 being detected. These generated gases can be readily captured and removed by NaOH solution. The reacted solids were further found to be various metal fluorides, thus revealing that SF6 removal takes place by reacting with various metal oxides and silicate in the sludge. Moreover, the kinetic investigation revealed that the SF6 reaction with the sludge is a first-order chemically controlled process. This research thus demonstrates that the waste electroplating sludge can be potentially used as an effective removal agent for one of the notorious greenhouse gases, SF6.
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Deficiency of TDAG51 protects against atherosclerosis by modulating apoptosis, cholesterol efflux, and peroxiredoxin-1 expression.
J Am Heart Assoc
PUBLISHED: 05-21-2013
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Apoptosis caused by endoplasmic reticulum (ER) stress contributes to atherothrombosis, the underlying cause of cardiovascular disease (CVD). T-cell death-associated gene 51 (TDAG51), a member of the pleckstrin homology-like domain gene family, is induced by ER stress, causes apoptosis when overexpressed, and is present in lesion-resident macrophages and endothelial cells.
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Tunable dual-band negative refractive index in ferrite-based metamaterials.
Opt Express
PUBLISHED: 05-15-2013
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A tunable dual-band ferrite-based metamaterial has been investigated by experiments and simulations. The negative permeability is realized around the ferromagnetic resonance (FMR) frequency which can be influenced by the dimension of the ferrites. Due to having two negative permeability frequency regions around the two FMR frequencies, the metamaterials consisting of metallic wires and ferrite rods with different sizes possess two passbands in the transmission spectra. The microwave transmission properties of the ferrite-based metamaterials can be not only tuned by the applied magnetic field, but also adjusted by the dimension of the ferrite rods. A good agreement between experimental and simulated results is demonstrated, which confirms that the tunable dual-band ferrite-based metamaterials can be used for cloaks, antennas and absorbers.
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Global transcriptome analysis of Escherichia coli exposed to immobilized anthraquinone-2-sulfonate and azo dye under anaerobic conditions.
Appl. Microbiol. Biotechnol.
PUBLISHED: 04-12-2013
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The immobilization of quinone compounds is regarded as a promising strategy to accelerate anaerobic decolorization of xenobiotic compounds azo dyes in the presence of quinone-reducing microorganisms. However, little is known about the basic response of these microorganisms to immobilized quinones in the presence of azo dyes. In the present study, whole-genome DNA microarrays were used to investigate a quinone-reducing bacterium Escherichia coli K-12 transcription response to immobilized anthraquinone-2-sulfonate (AQSim) reduction and azo dye acid red 18 (AR 18) decolorization. Transcriptome analysis showed that AQSim was more accessible for the cells of E. coli K-12 than AR 18. Despite there being some differences between AQSim and soluble AQS mediated decolorization of AR 18, AQSim reduction and AR 18 decolorization, more similarity could be observed in the four processes. Among over 60 % shared genes, several groups of genes exhibited high expression levels, including those genes encoding terminal reductases, menaquinone biosynthesis, formate dehydrogenases and outer membrane proteins. Especially, nrfABCD, frdBCD and dsmABC encoding terminal reductases were significantly upregulated. Further gene deletion experiments demonstrated that the above three groups of genes were involved in AQSim-mediated AR 18 decolorization. In addition, significant upregulation of stress response genes was observed, which indicated the adaptation of E. coli K-12 to AQSim and AR 18 exposures.
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A potentially functional polymorphism in the regulatory region of let-7a-2 is associated with an increased risk for diabetic nephropathy.
Gene
PUBLISHED: 04-10-2013
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Diabetic nephropathy (DN) is a major diabetic complication. However, the initiating molecular events triggering DN are unknown. MicroRNAs (miRNAs) have recently been identified as regulators that modulate the target gene expression and are involved in DN. However, the evidence of the mechanism is still insufficient in human samples. In this study, microRNA microarray assay was used to study gene differential expression profiles in DN and diabetes mellitus (DM) patients. One of the specific differentially expressed microRNAs, let-7a, was down-expressed in DN. Additionally, the expression of let-7a was also decreased in DN by real-time RT PCR in the patients samples. Moreover, single nucleotide polymorphism (SNP) analysis was used to evaluate the relationship between three SNPs in the regulatory region of let-7a-2 gene and the risk of DN in the Chinese Han population by means of PCR-restriction fragment length polymorphism (RFLP-PCR). Also, the genotype and allele frequencies of let-7a-2 polymorphism were tested in 274 individuals, including 108 DN, 104 DM patients and 62 health control individuals (CON). It was found that a variant rs1143770 and the distributions of CT/TT genotypes were significantly different in three groups, and the CT+TT genotypes frequencies were significantly higher in DN and DM groups than that in CON group. In conclusion, let-7a-2 might participate in the regulation of the occurrence of DN, and a potential variant rs1143770 was significantly associated with the increased risk for DN.
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Surfactant-free CuInS2 nanocrystals: an alternative counter-electrode material for dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 04-10-2013
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Surfactant-free CuInS2 (CIS) nanocrystals (NCs) were synthesized by replacing organic capping ligands with inorganic ions S(2-). The efficacy of ligand exchange was probed by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis spectroscopy, and Fourier-transform infrared (FTIR). The surfactant-free CIS NCs films were obtained by drop-casting onto the clean FTO glass. The electrical conductivity and electrocatalytic activity of CIS NCs films were sharply increased due to the improved interparticle coupling after ligand exchange. When the surfactant-free CIS films were used as counter electrode (CE) in dye-sensitized solar cells (DSSCs), a conversion efficiency of ? = 5.77% was achieved without sintering.
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Powerful tests for association on quantitative trait loci incorporating imprinting effects.
J. Hum. Genet.
PUBLISHED: 04-04-2013
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Genomic imprinting is an important epigenetic factor in complex traits study, and there has recently been considerable interest in association study for quantitative traits by incorporating imprinting. However, these methods need the assumptions of Hardy-Weinberg equilibrium or only use information from families with one child. In this paper, by taking imprinting into account and making no assumption about the distribution of the quantitative traits, we propose two novel classes of Q-C-TDTI(c) and Q-C-MAX(c) family-based association tests for quantitative traits. The tests flexibly accommodate family data with missing parental genotype and with multiple siblings. Q-C-TDTI(c) is derived from a two-stage analysis, where in the first stage Q-C-PAT(c) is applied to test for imprinting effects and in the second stage we select the most appropriate statistic among three transmission disequilibrium tests for association according to the finding from Q-C-PAT(c). Another proposed Q-C-MAX(c) approach takes the maximum of the three statistics. Compared with the existing alternative methods, the simulation results demonstrate that the two proposed tests are robust to population stratification and have better performance for testing association under various scenarios. Further, the powerful and versatile Q-C-TDTI(c) test is applied to analyze Framingham Heart Study data.
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Effects of different cold-air exposure intensities on the risk of cardiovascular disease in healthy and hypertensive rats.
Int J Biometeorol
PUBLISHED: 01-31-2013
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Ten-week-old male Wistar rats (systolic blood pressure, 106-116 mmHg; body weight, 300-320 g) and spontaneously hypertensive rats (systolic blood pressure, 160-176 mmHg; body weight, 210.9-244.9 g) were used as healthy and hypertensive subjects to determine the effects of varying degrees of cold-air exposure in a climate chamber box. The three cold-air ranks were cold air I [minimum temperature (TMIN) 6.4 °C, ??T(48) 8.6 °C], cold air II (TMIN 3.8 °C, ??T(48) 11.2 °C), and cold air III (TMIN -0.3 °C, ??T(48) 15.3 °C), as established from the cold-air data of Zhangye City, China. Each cold-air rank consisted of a temperature drop and a temperature increase with the same initial and terminal temperatures (15 °C). After cold-air exposure, the risk factors for cardiovascular disease (CVD) such as systolic blood pressure, whole blood viscosity (10/s and 150/s), plasma fibrinogen, and blood lipids of the rats were determined. The results indicated that the CVD risk factors of the healthy and hypertensive rats increased significantly with cold-air exposure intensities. The increase in systolic blood pressure was greater during temperature drops, whereas the increases in whole blood viscosity and plasma fibrinogen were greater after cold-air exposure. The effects of cold-air exposure on the CVD risk factors of healthy rats, particularly the systolic blood pressure, whole blood viscosity (150/s), and LDL/HDL, were greater than those in hypertensive rats. In conclusion, CVD risk may increase with cold-air ranks. Blood pressure-induced CVD risk may be greater during cold-air temperature drop, whereas atherosclerosis-induced CVD risk may be greater after cold-air exposure. The effect of cold air on the CVD risk factors in healthy subjects may be more significant than those in hypertensive subjects.
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A developmental framework for complex plasmodesmata formation revealed by large-scale imaging of the Arabidopsis leaf epidermis.
Plant Cell
PUBLISHED: 01-31-2013
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Plasmodesmata (PD) form tubular connections that function as intercellular communication channels. They are essential for transporting nutrients and for coordinating development. During cytokinesis, simple PDs are inserted into the developing cell plate, while during wall extension, more complex (branched) forms of PD are laid down. We show that complex PDs are derived from existing simple PDs in a pattern that is accelerated when leaves undergo the sink-source transition. Complex PDs are inserted initially at the three-way junctions between epidermal cells but develop most rapidly in the anisocytic complexes around stomata. For a quantitative analysis of complex PD formation, we established a high-throughput imaging platform and constructed PDQUANT, a custom algorithm that detected cell boundaries and PD numbers in different wall faces. For anticlinal walls, the number of complex PDs increased with increasing cell size, while for periclinal walls, the number of PDs decreased. Complex PD insertion was accelerated by up to threefold in response to salicylic acid treatment and challenges with mannitol. In a single 30-min run, we could derive data for up to 11k PDs from 3k epidermal cells. This facile approach opens the door to a large-scale analysis of the endogenous and exogenous factors that influence PD formation.
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Enhanced performance of dye-sensitized solar cells using solution-based in situ synthesis and fabrication of Cu2ZnSnSe4 nanocrystal counter electrode.
Chemistry
PUBLISHED: 01-25-2013
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On the bright side: A solution-based strategy was developed for in situ synthesis and film deposition of Cu2ZnSnSe4 nanocrystal films (samples a-d). The obtained Cu2ZnSnSe4 nanocrystal films can be used as an effective counter-electrode (CE) material to replace Pt, and yield low-cost, high-efficiency dye-sensitized solar cells (DSSCs). The assembled solar cell devices exhibit an efficiency of 7.82?% under 1?sun irradiation (see figure).
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New ent-abietane and ent-kaurane diterpenoids from Isodon rubescens.
Chem. Pharm. Bull.
PUBLISHED: 01-11-2013
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Five new ent-abietane diterpenoids, ent-abierubesins A-E (1-5), and two new ent-kauranoids, hubeirubesins A and B (6, 7), together with three known diterpenoids (8-10), were isolated from the aerial parts of Isodon rubescens. Their structures were identified by means of extensive spectroscopic analysis, and the absolute stereochemistry of 1 was determined by single-crystal X-ray diffraction experiment.
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Highly efficient construction of oriented sandwich structures for surface-enhanced Raman scattering.
Nanotechnology
PUBLISHED: 01-08-2013
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The purpose of this study is to solve the problem of low achievement in fabricating sandwich surface-enhanced Raman scattering (SERS) substrates. We demonstrated a highly efficient sandwich structure by the oriented assembly of metal nanoparticles (NPs) on a periodic hexagonal array of metal nanoprisms with 1,4-benzenedithiol (1,4-BDT) as linkers. The metal nanoprism array was prepared by vacuum deposition of metal on a close-packed polystyrene nanosphere pre-patterned substrate. The metal nanoprism array presents different surface properties from the pits left from the removal of polystyrene nanospheres, which causes linkers to selectively adsorb on the metal nanoprism array and sequentially leads to the oriented immobilization of the second-layer metal NPs, avoiding mismatched orientation. These sandwich SERS substrates were characterized by extinction spectroscopy and atomic force microscopy and their enhancement activity was evaluated under different excitation wavelengths. The sandwich structure greatly increases the achievement of hot spots to almost 100% of all the metal nanoprisms and enables a large amplification of SERS signals by a factor of ten. This method has the advantages of simplicity, high efficiency, high throughput, controllability and high reproducibility. It has significance in both the study of SERS substrates and the development of plasmonic devices.
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Improvement in visual function and quality of life following a blindness prevention surgery program in a rural area of Eastern China.
Exp Ther Med
PUBLISHED: 01-03-2013
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The aim of this study was to assess the changes in visual function (VF) and quality of life (QOL) among patients following blindness prevention surgery in a rural area of Eastern China. The prospective study selected cataract patients via mobile eye screening camps. VF and QOL questionnaires originally developed by Fletcher et al were completed prior to and 6 months after surgery. Small-incision cataract surgery (SICS) with posterior chamber intraocular lens (IOL) implantation was performed on patients by a blindness prevention surgery group. The VF and QOL scores of 178 cataract patients preoperatively were 48.58±31.18 and 65.97±26.77, respectively. The scores decreased in proportion to decreasing vision status. The VF and QOL scale scores were significantly correlated with the vision grade of the patient (rVF=-17.2093, t=-10.87, P<0.001, rQOL=-13.1399, t=-8.87, P<0.001) and age (rVF=-0.6505, t=-3.87, P<0.001, rQOL=- 0.3309, t=-2.10, P=0.037). A total of 131 patients responded to the second survey, VF and QOL scores increased significantly over a six-month postoperative period (VF=83.21±16.40, P<0.001; QOL=86.53±16.33, P<0.001). The VF scale scores were correlated with the grade of vision and residence area, the QOL scale scores were correlated with the grade of vision and gender. The VF and QOL of patients were significantly improved by performing SICS with posterior chamber IOL implantation collectively in a short period in rural areas of Eastern China. It is important to follow-up cataract patients postoperatively as untreated complications of the surgery may affect the stability of VF and QOL postoperatively.
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Unipolar memristive Switching in Bulk Negative Temperature Coefficient Thermosensitive Ceramics.
PLoS ONE
PUBLISHED: 01-01-2013
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A memristive phenomenon was observed in macroscopic bulk negative temperature coefficient nickel monoxide (NiO) ceramic material. Current-voltage characteristics of memristors, pinched hysteretic loops were systematically observed in the Ag/NiO/Ag cell. A thermistor-based model for materials with negative temperature coefficient was proposed to explain the mechanism of the experimental phenomena. Most importantly, the results demonstrate the potential for a realization of memristive systems based on macroscopic bulk materials.
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Powerful haplotype-based Hardy-Weinberg equilibrium tests for tightly linked loci.
PLoS ONE
PUBLISHED: 01-01-2013
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Recently, there have been many case-control studies proposed to test for association between haplotypes and disease, which require the Hardy-Weinberg equilibrium (HWE) assumption of haplotype frequencies. As such, haplotype inference of unphased genotypes and development of haplotype-based HWE tests are crucial prior to fine mapping. The goodness-of-fit test is a frequently-used method to test for HWE for multiple tightly-linked loci. However, its degrees of freedom dramatically increase with the increase of the number of loci, which may lack the test power. Therefore, in this paper, to improve the test power for haplotype-based HWE, we first write out two likelihood functions of the observed data based on the Nius model (NM) and inbreeding model (IM), respectively, which can cause the departure from HWE. Then, we use two expectation-maximization algorithms and one expectation-conditional-maximization algorithm to estimate the model parameters under the HWE, IM and NM models, respectively. Finally, we propose the likelihood ratio tests LRT[Formula: see text] and LRT[Formula: see text] for haplotype-based HWE under the NM and IM models, respectively. We simulate the HWE, Nius, inbreeding and population stratification models to assess the validity and compare the performance of these two LRT tests. The simulation results show that both of the tests control the type I error rates well in testing for haplotype-based HWE. If the NM model is true, then LRT[Formula: see text] is more powerful. While, if the true model is the IM model, then LRT[Formula: see text] has better performance in power. Under the population stratification model, LRT[Formula: see text] is still more powerful. To this end, LRT[Formula: see text] is generally recommended. Application of the proposed methods to a rheumatoid arthritis data set further illustrates their utility for real data analysis.
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An extremely broad band metamaterial absorber based on destructive interference.
Opt Express
PUBLISHED: 11-24-2011
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We propose a design of an extremely broad frequency band absorber based on destructive interference mechanism. Metamaterial of multilayered SRRs structure is used to realize a desirable refractive index dispersion spectrum, which can induce a successive anti-reflection in a wide frequency range. The corresponding high absorptance originates from the destructive interference of two reflection waves from the two surfaces of the metamaterial. A strongly absorptive bandwidth of almost 60 GHz is demonstrated in the range of 0 to 70 GHz numerically. This design provides an effective and feasible way to construct broad band absorber in stealth technology, as well as the enhanced transmittance devices.
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Effect of highly ordered single-crystalline TiO2 nanowire length on the photovoltaic performance of dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 10-13-2011
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One-dimensional semiconductor nanostructures grown directly onto transparent conducting oxide substrates with a high internal surface area are most desirable for high-efficiency dye-sensitized solar cells (DSSCs). Herein, we present a multicycle hydrothermal synthesis process to produce vertically aligned, single crystal rutile TiO(2) nanowires with different lengths between 1 and 8 ?m for application as the working electrode in DSSCs. Optimum performance was obtained with a TiO(2) nanowire length of 2.0 ?m, which may be ascribed to a smaller nanowire diameter with a high internal surface area and better optical transmittance with an increase in the incident light intensity on the N719 dye; as well as a firm connection at the FTO/TiO(2) nanowire interface.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.