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Find video protocols related to scientific articles indexed in Pubmed.
Silicon microring modulator for 40 Gb/s NRZ-OOK metro networks in O-band.
Opt Express
PUBLISHED: 11-18-2014
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A microring-based silicon modulator operating at 40 Gb/s near 1310 nm is demonstrated for the first time to our knowledge. NRZ-OOK signals at 40 Gb/s with 6.2 dB extinction ratio are observed by applying a 4.8 Vpp driving voltage and biasing the modulator at 7 dB insertion loss point. The energy efficiency is 115 fJ/bit. The transmission performance of 40 Gb/s NRZ-OOK through 40 km of standard single mode fiber without dispersion compensation is also investigated. We show that the link suffers negligible dispersion penalty. This makes the modulator a potential candidate for metro network applications.
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[Selective Laser Sintering-produced porous titanium alloy scaffold for bone tissue engineering].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-22-2014
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To evaluate the biocompatibility of SLS-produced titanium alloy scaffold in vitro and investigate the therapeutic effects in repairing segmental bone defects.
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Preparation of highly substituted (?-acylamino)acrylates via iron-catalyzed alkoxycarbonylation of N-vinylacetamides with carbazates.
Chem. Commun. (Camb.)
PUBLISHED: 08-21-2014
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An efficient iron(II)-catalyzed alkoxycarbonylation reaction between N-vinylacetamides and carbazates is reported. The corresponding useful highly substituted (?-acylamino)acrylates could be obtained in reasonable to good yields and stereoselectivity under mild reaction conditions.
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Experimental demonstration of broadband Lorentz non-reciprocity in an integrable photonic architecture based on Mach-Zehnder modulators.
Opt Express
PUBLISHED: 08-05-2014
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Lorentz reciprocity is a direct consequence of Maxwell equations governing the propagation of light in passive linear media with symmetric permittivity and permeability tensors. Here, we demonstrate the first active optical isolator and circulator implemented in a linear and reciprocal material platform using commercial Mach-Zehnder modulators. In a proof-of-principle experiment based on single-mode polarization-maintaining fibers, we achieve more than 12.5 dB isolation over an unprecedented 8.7 THz bandwidth at telecommunication wavelengths, with only 9.1 dB total insertion loss. Our architecture provides a practical answer to the challenge of non-reciprocal light routing in photonic integrated circuits.
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Silicon Mod-MUX-Ring transmitter with 4 channels at 40 Gb/s.
Opt Express
PUBLISHED: 07-01-2014
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We propose for the first time the Mod-MUX-Ring architecture for microring based WDM transmitter. A prototype Mod-MUX-Ring transmitter with 4 channels and 400 GHz channel spacing is demonstrated and fully characterized at 40 Gb/s channel rate. Under 2.7 V driving voltage, error-free (BER < 10(-12)) operation is achieved on all channels, with 3 dB extinction ratio. Performance comparisons to Lithium Niobate modulators are made.
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[Associations of ulcerative colitis with vitamin D receptor gene polymorphisms and serum levels of 25-hydroxyl vitamin D].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-24-2014
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To explore the associations of ulcerative colitis (UC) with vitamin D receptor (VDR) gene polymorphisms and serum levels of 25-hydroxyl vitamin D[25(OH)D].
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Template-Induced Diverse Metal-Organic Materials as Catalysts for the Tandem Acylation-Nazarov Cyclization.
Chemistry
PUBLISHED: 04-18-2014
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In our continuing quest to develop a metal-organic framework (MOF)-catalyzed tandem pyrrole acylation-Nazarov cyclization reaction with ?,?-unsaturated carboxylic acids for the synthesis of cyclopentenone[b]pyrroles, which are key intermediates in the synthesis of natural product (±)-roseophilin, a series of template-induced Zn-based (1-3) metal-organic frameworks (MOFs) have been solvothermally synthesized and characterized. Structural conversions from non-porous MOF 1 to porous MOF 2, and back to non-porous MOF 3 arising from the different concentrations of template guest have been observed. The anion-? interactions between the template guests and ligands could affect the configuration of ligands and further tailor the frameworks of 1-3. Futhermore, MOFs 1-3 have shown to be effective heterogeneous catalysts for the tandem acylation-Nazarov cyclization reaction. In particular, the unique structural features of 2, including accessible catalytic sites and suitable channel size and shape, endow 2 with all of the desired features for the MOF-catalyzed tandem acylation-Nazarov cyclization reaction, including heterogeneous catalyst, high catalytic activity, robustness, and excellent selectivity. A plausible mechanism for the catalytic reaction has been proposed and the structure-reactivity relationship has been further clarified. Making use of 2 as a heterogeneous catalyst for the reaction could greatly increase the yield of total synthesis of (±)-roseophilin.
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Inflammatory modulation effect of glycopeptide from Ganoderma capense (Lloyd) Teng.
Mediators Inflamm.
PUBLISHED: 02-25-2014
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Glycopeptide from Ganoderma capense (Lloyd) Teng (GCGP) injection is widely used in kinds of immune disorders, but little is known about the molecular mechanisms of how GCGP could interfere with immune cell function. In the present study, we have found that GCGP had inflammatory modulation effects on macrophage cells to maintain NO production and iNOS expression at the normal level. Furthermore, western blot analysis showed that the underlying mechanism of immunomodulatory effect of GCGP involved NF-?B p65 translation, I ?B phosphorylation, and degradation; NF-?B inhibitor assays also confirmed the results. In addition, competition study showed that GCGP could inhibit LPS from binding to macrophage cells. Our data indicates that GCGP, which may share the same receptor(s) expressed by macrophage cells with LPS, exerted immunomodulatory effect in a NF-?B-dependent signaling pathway in macrophages.
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Role of berberine in anti-bacterial as a high-affinity LPS antagonist binding to TLR4/MD-2 receptor.
BMC Complement Altern Med
PUBLISHED: 02-18-2014
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Berberine is an isoquinoline alkaloid mainly extracted from Rhizoma Coptidis and has been shown to possess a potent inhibitory activity against bacterial. However, the role of berberine in anti-bacterial action has not been extensively studied.
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Preparation and immunomodulating activities of a library of low-molecular-weight ?-glucans.
Carbohydr Polym
PUBLISHED: 01-26-2014
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YCP, an ?-D-glucan with molecular weight of 2.4 × 10(3)kDa, was isolated from the mycelium of marine fungus Phoma herbarum YS4108. It interacted with TLR2 and TLR4 to induce B cells proliferation and activation. Here, a series of homogenous LMWYCPs (namely LMWYCP-1 to LMWYCP-6) were obtained by acid degradation. LMWYCP-3 and LMWYCP-4 were capable of inducing the proliferation of B cells dramatically. Further research involved TLR defunctionalization and competitive binding assay demonstrated that the immunomodulating activities of LMWYCP-4 was TLR4-dependent but TLR2-independent, while that mediated by LMWYCP-3 was neither TLR2- nor TLR4-dependent. Together with the structural information that LMWYCPs shared the similar structure features with YCP, we deduced that LMWYCP-4 may be the functional unit of YCP responsible for YCP/TLR4 interaction. This is the first time that the probable functional unit of glucan with the structure of ?-D-(1-4)-linked residues in main chain and ?-D-(1-6)-linked residues in branches is reported.
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Abundance and distribution of Macrolide-Lincosamide-Streptogramin resistance genes in an anaerobic-aerobic system treating spiramycin production wastewater.
Water Res.
PUBLISHED: 01-15-2014
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The behaviors of the Macrolide-Lincosamide-Streptogramin (MLS) resistance genes were investigated in an anaerobic-aerobic pilot-scale system treating spiramycin (SPM) production wastewater. After screening fifteen typical MLS resistance genes with different mechanisms using conventional PCR, eight detected genes were determined by quantitative PCR, together with three mobile elements. Aerobic sludge in the pilot system exhibited a total relative abundance of MLS resistance genes (per 16S rRNA gene) 2.5 logs higher than those in control samples collected from sewage and inosine wastewater treatment systems (P < 0.05), implying the presence of SPM could induce the production of MLS resistance genes. However, the total relative gene abundance in anaerobic sludge (4.3 × 10(-1)) was lower than that in aerobic sludge (3.7 × 10(0)) despite of the higher SPM level in anaerobic reactor, showing the advantage of anaerobic treatment in reducing the production of MLS resistance genes. The rRNA methylase genes (erm(B), erm(F), erm(X)) were the most abundant in the aerobic sludge (5.3 × 10(-1)-1.7 × 10(0)), followed by esterase gene ere(A) (1.3 × 10(-1)) and phosphorylase gene mph(B) (5.7 × 10(-2)). In anaerobic sludge, erm(B), erm(F), ere(A), and msr(D) were the major ones (1.2 × 10(-2)-3.2 × 10(-1)). These MLS resistance genes (except for msr(D)) were positively correlated with Class 1 integron (r(2) = 0.74-0.93, P < 0.05), implying the significance of horizontal transfer in their proliferation.
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Preparation, optimization and application of affinity absorbent with a polysaccharide YCP as the ligand.
Carbohydr Polym
PUBLISHED: 01-03-2014
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YCP, an ?-glucan from the mycelium of marine filamentous fungus Phoma herbarum YS4108, has great antitumor potential via enhancement of host immune through Toll-like receptor (TLR) 2 and TLR4 signaling. In the current study, YCP was coupled to EAH Sepharose 4B agarose beads to prepare the YCP-Sepharose affinity absorbent using 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) as the activating agent. An orthogonal experiment L9 (3)(4) was applied to optimize the coupling procedure, giving the optimal parameters as follows: molar ratio of CDAP to YCP of 1:2, CDAP-activation time of 5 min, gel volume of 0.1 mL, and gel-incubation time of 72 h, respectively. Scanning electron microscopy analysis indicated successfully preparation of YCP immobilized sepharose beads, while these beads essentially maintained biological properties of free YCP since they can interact with TLR2 and TLR4 specifically at comparable level. Collectively, our findings provide an alternative approach to immobilize carbohydrate-based molecules for studying the carbohydrate-protein interaction.
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Safety of surgical treatment for patients with scoliosis and surgically corrected congenital cardiac malformations: a comparison with patients with scoliosis and normal hearts.
J Neurosurg Pediatr
PUBLISHED: 09-13-2013
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The safety of spinal fusion has been poorly studied in children with surgically corrected congenital cardiac malformations (CCMs). The objective of this study was to evaluate the safety of spinal fusion in patients with CCMs following cardiac surgery.
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Broadband on-chip optical non-reciprocity using phase modulators.
Opt Express
PUBLISHED: 06-22-2013
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Breaking the reciprocity of light propagation in a nanoscale photonic integrated circuit (PIC) is a topic of intense research, fostered by the promises of this technology in areas ranging from experimental research in classical and quantum optics to high-rate telecommunications and data interconnects. In particular, silicon PICs fabricated in processes compatible with the existing complementary metal-oxide-semiconductor (CMOS) infrastructure have attracted remarkable attention. However, a practical solution for integrating optical isolators and circulators within the current CMOS technology remains elusive. Here, we introduce a new non-reciprocal photonic circuit operating with standard single-mode waveguides or optical fibers. Our design exploits a time-dependent index modulation obtained with conventional phase modulators such as the one widely available in silicon photonics platforms. Because it is based on fully balanced interferometers and does not involve resonant structures, our scheme is also intrinsically broadband. Using realistic parameters we calculate an extinction ratio superior to 20dB and insertion loss below 3dB.
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C-C cross-coupling of primary and secondary benzylic alcohols using supported gold-based bimetallic catalysts.
ChemSusChem
PUBLISHED: 03-26-2013
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Clean alcohol-alcohol cross-coupling: A clean and efficient one-pot direct C-C cross-coupling of equimolar amounts of primary and secondary alcohols by a facile hydrogen autotransfer pathway is achieved over a robust and easily recovered hydrotalcite-supported Au-Pd bimetallic catalyst system. A variety of primary and secondary alcohols have been selectively converted into the corresponding ?-alkylated ketones in good yields.
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Toll-like receptor 2 and Toll-like receptor 4-dependent activation of B cells by a polysaccharide from marine fungus Phoma herbarum YS4108.
PLoS ONE
PUBLISHED: 03-02-2013
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Various natural polysaccharides are capable of activating the immune system and therefore can be employed as biological response modifiers in anti-tumor therapy. We previously found a homogenous polysaccharide from the mycelium of marine fungus Phoma herbarum YS4108, named YCP, exhibiting strong in vivo antitumor ability via enhancement of the host immune responses. To further elucidate the role of YCP as a biological response modifier, the immunomodulating activities of YCP in B cells was investigated in the current study. We demonstrated that stimulation of YCP with murine splenic B cells resulted in cell proliferation and generation of IgM antibody response. Binding of YCP to B cells was a direct, saturable and reversible event and required TLR2 and TLR4 involvement. TLR2 and TLR4 defunctionalization by either antibody blocking or allele-specific mutation significantly impaired the B-cell proliferative and IgM responses to YCP. YCP interaction with TLR2 and TLR4 led to the activation of intracellular p38, ERK and JNK, as well as the translocation of transcriptional factor NF-?B into nucleus. Furthermore, specific inhibitors of p38, ERK, JNK and NF-?B could attenuate the ability of YCP to induce B cell proliferation and IgM production. Taken together, this study has indicated for the first time the immunostimulating properties of YCP on B cells through a receptor-mediated mechanism, which involves TLR2 and TLR4 and resultant activation of MAPK and NF-?B signaling pathways, thereby highlighting the role of YCP as an efficacious biological response modifier in oncologic immunotherapy.
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A Comparative Theoretical and Computational Study on Robust Counterpart Optimization: I. Robust Linear Optimization and Robust Mixed Integer Linear Optimization.
Ind Eng Chem Res
PUBLISHED: 09-22-2011
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Robust counterpart optimization techniques for linear optimization and mixed integer linear optimization problems are studied in this paper. Different uncertainty sets, including those studied in literature (i.e., interval set; combined interval and ellipsoidal set; combined interval and polyhedral set) and new ones (i.e., adjustable box; pure ellipsoidal; pure polyhedral; combined interval, ellipsoidal, and polyhedral set) are studied in this work and their geometric relationship is discussed. For uncertainty in the left hand side, right hand side, and objective function of the optimization problems, robust counterpart optimization formulations induced by those different uncertainty sets are derived. Numerical studies are performed to compare the solutions of the robust counterpart optimization models and applications in refinery production planning and batch process scheduling problem are presented.
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[Cartilage changes of femoral head osteonecrosis in stage II and III as detected by dGEMRIC].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 09-15-2011
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To detect the cartilage changes of hip joint with osteonecrosis of femoral head (ONFH) in stages II and III and provide evidence for understanding cartilage changes of femoral head of osteonecrosis before collapse.
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Photolithographically fabricated low-loss asymmetric silicon slot waveguides.
Opt Express
PUBLISHED: 06-07-2011
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We demonstrate low-loss asymmetric slot waveguides in silicon-on-insulator (SOI). 130 and 180 nm wide slots were fabricated with a 248 nm stepper, in 200 nm thick silicon. An asymmetric waveguide design is shown to expand the range in which the TE0 mode is guided and suppress the TE1 mode, while still maintaining a sharp concentration of electric field in the center of the slot. Optical propagation losses of 2 dB/cm or less are shown for asymmetric slot waveguides with 130 nm wide slots and 320 and 100 nm wide arms.
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Silicon-polymer hybrid slot waveguide ring-resonator modulator.
Opt Express
PUBLISHED: 03-04-2011
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We demonstrate a ring-resonator modulator based on a silicon-polymer hybrid slot waveguide with a tunability of 12.7 pm/V at RF speeds and a bandwidth of 1 GHz, for optical wavelengths near 1550 nm. Our slot waveguides were fabricated with 193 nm optical lithography, as opposed to the electron beam lithography used for previous results. The tunability is comparable to some of the best ring-based modulators making use of the plasma dispersion effect. The speed is likely limited only by resistance in the strip-loading section, and it should be possible to realize significant improvement with improved processing.
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Low-loss strip-loaded slot waveguides in silicon-on-insulator.
Opt Express
PUBLISHED: 12-18-2010
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Electro-optic polymer-clad silicon slot waveguides have recently been used to build a new class of modulators, that exhibit very high bandwidths and extremely low drive voltages. A key step towards making these devices practical will be lowering optical insertion losses. We report on the first measurements of low-loss waveguides that are geometrically suitable for high bandwidth slot waveguide modulators: a strip-loaded slot waveguide. Waveguide loss for undoped waveguides of 6.5 ± 0.2 dB/cm was achieved with 40 nm thick strip-loading, with the full silicon thickness around 220 nm and a slot size of 200 nm, for wavelengths near 1550 nm.
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Temporal dynamics of two-photon-pumped amplified spontaneous emission in slab organic crystals.
Opt Lett
PUBLISHED: 08-04-2010
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We have studied the ultrafast dynamics of two-photon-pumped amplified spontaneous emission (ASE) from a single crystal by the time-resolved fluorescence upconversion technique. With the increase of two-photon pump intensities, the emission decay time is dramatically shortened by 30 times (from 3ns to approximately 87 ps), and the energy migration rate is acutely enhanced when ASE occurs. The stripe length is also found to play an important role in the formation of the ASE. Meanwhile, the gain coefficient is evaluated to be 15cm(-1) for 560nm at an excitation intensity of 2.3mJ/pulse/cm(2) by the variable stripe length technique.
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Comparison of archaeal and bacterial community structures in heavily oil-contaminated and pristine soils.
J. Biosci. Bioeng.
PUBLISHED: 04-27-2009
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Archaeal and bacterial community structures in heavily oil-contaminated and pristine soils were compared using denaturing gradient gel electrophoresis and 16S rRNA gene libraries. The results showed that archaeal diversity was more complex in the contaminated soil than in the uncontaminated control soil. Archaeal populations in the contaminated soil consisted mainly of Euryarchaeota, with abundant methanogen-like operational taxonomic units (OTUs) and OTUs related to the phylogenetically diverse group, candidate division I, corresponding to rice cluster V. In contrast, only halophilic archaea were found in the pristine soil. Bacterial community structures also differed significantly between the contaminated and pristine soils. More clones from the contaminated soil were related to known hydrocarbon-degrading bacteria, implying that microorganisms with the potential to degrade petroleum were well-established. These results provide further insights into the composition of microbial communities in oil-contaminated soils.
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Response of activated sludge to the treatment of oxytetracycline production waste stream.
Appl. Microbiol. Biotechnol.
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To investigate how the microbial community in activated sludge responded to high antibiotic levels, a bench-scale aerobic wastewater treatment system was used to treat oxytetracycline (OTC) mother liquor (OTC-ML). Removal efficiency of chemical oxygen demand decreased from 64.9 to 51.0 % when the OTC level increased from 191.6 to 620.5 mg/L, respectively. According to the cloning results, Psychrobacter and Cryptophyta were the dominant bacterium and eukaryote in the inoculated sludge, respectively, both of which related to low temperature. After OTC exposure, Alphaproteobacteria and Betaproteobacteria became the dominant bacteria, with a small proportion of Firmicutes, Actinobacteria appeared, and fungi (mainly Saccharomycotina) became the dominant eukaryotes, indicating the possible functions of these microorganisms in the wastewater treatment of OTC-ML. The relative abundance of nine tetracycline resistance genes and four mobile elements (class 1 integron, class 2 integron, transposon Tn916/1545, and pattern 1 insertion sequence common region) significantly increased from undetectable to 2.1?×?10(-3) in the inoculated sludge to 1.7?×?10(-4)-9.8?×?10(-1) in sludge exposed to 620.5 mg/L OTC by using real-time PCR. The variety of gene cassette arrays of class 1 integron in the sludge samples increased with increasing OTC exposure concentration.
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An unusual chemoselective hydrogenation of quinoline compounds using supported gold catalysts.
J. Am. Chem. Soc.
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The pursuit of modern sustainable chemistry has stimulated the development of innovative catalytic processes that enable chemical transformations to be performed under mild and clean conditions with high efficiency. Herein, we report that gold nanoparticles supported on TiO(2) catalyze the chemoselective hydrogenation of functionalized quinolines with H(2) under mild reaction conditions. Our results point toward an unexpected role for quinolines in gold-mediated hydrogenation reactions, namely that of promoter; this is in stark contrast to what prevails in the traditional noble metal Pd-, Pt-, and Ru-based catalyst systems, in which quinolines and their derivatives typically act as poisons. As a result of the remarkable promotional effect of quinoline molecules to H(2) activation over supported gold, the transformation can proceed smoothly under very mild conditions (even at temperatures as low as 25 °C). Of practical significance is that various synthetically useful functional groups including halogens, ketone, and olefin remain intact during the hydrogenation of quinolines. Moreover, the protocol also shows promise for the regiospecific hydrogenation of the heterocyclic ring of a variety of other biologically important heteroaromatic nitrogen compounds, such as isoquinoline, acridine, and 7,8-benzoquinoline, in a facile manner. Apart from its importance in catalytic hydrogenation, we believe that this intriguing self-promoted effect by reactant molecules may have fundamental implications for the broad field of gold catalysis and form the basis for development of new catalytic procedures for other key transformations.
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Ultralow drive voltage silicon traveling-wave modulator.
Opt Express
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There has been great interest in the silicon platform as a material system for integrated photonics. A key challenge is the development of a low-power, low drive voltage, broadband modulator. Drive voltages at or below 1 Vpp are desirable for compatibility with CMOS processes. Here we demonstrate a CMOS-compatible broadband traveling-wave modulator based on a reverse-biased pn junction. We demonstrate operation with a drive voltage of 0.63 Vpp at 20 Gb/s, a significant improvement in the state of the art, with an RF energy consumption of only 200 fJ/bit.
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Bandwidth enhancement of waveguide-coupled photodetectors with inductive gain peaking.
Opt Express
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Silicon has recently attracted a great deal of interest as an economical platform for integrated photonics systems. Integrated photodetectors are a key component of such systems, and CMOS-compatible processes involving epitaxially grown germanium for photodetection have been demonstrated. Detector parasitic capacitance is a key limitation, which will likely worsen if techniques such as bump bonding are employed. Here we propose leveraging the complexity available in silicon photonics processes to compensate for this using a technique known as gain peaking. We predict that by simply including an inductor and capacitor in the photodetector circuit with the properly chosen values, detector bandwidths can be as much as doubled, with no undesired effects.
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Cellular microRNA let-7c inhibits M1 protein expression of the H1N1 influenza A virus in infected human lung epithelial cells.
J. Cell. Mol. Med.
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The influenza virus (IV) triggers a series of signalling events inside host cells and induces complex cellular responses. Studies have suggested that host factors play an essential role in IV replication. MicroRNAs (miRNAs) represent a class of small non-coding RNAs that target mRNAs, triggering either translation repression or RNA degradation. Emerging research suggests that host-derived cellular miRNAs are involved in mediating the host-IV interaction. Using miRNA microarrays, we identified several miRNAs aberrantly expressed in IV-infected human lung epithelial cells (A549). Specifically, miR-let-7c was highly up-regulated in IV-infected A549 cells. PITA and miRanda database screening indicated that the let-7c seed sequence is a perfect complementary sequence match to the 3 untranslated region (UTR) of viral gene M1 (+) cRNA, but not to PB2 and PA. As detected by a luciferase reporter system, let-7c directly targeted the 3-UTR of M1 (+) cRNA, but not PB2 and PA. To experimentally identify the function of cellular let-7c, precursor let-7c was transfected into A549 cells. Let-7c down-regulated IV M1 expression at both the (+) cRNA and protein levels. Furthermore, transfection with a let-7c inhibitor enhanced the expression of M1. Therefore, let-7c may reduce IV replication by degrading M1 (+) cRNA. This is the first report indicating that cellular miRNA regulates IV replication through the degradation of viral gene (+) cRNA by matching the 3-UTR of the viral cRNA. These findings suggest that let-7c plays a role in protecting host cells from the virus in addition to its known cellular functions.
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Highly efficient heterogeneous gold-catalyzed direct synthesis of tertiary and secondary amines from alcohols and urea.
ChemSusChem
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Urea, the white gold: The efficient synthesis of tertiary and secondary amines is achieved by heterogeneous gold-catalyzed direct amination of stoichiometric alcohols with urea in good to excellent yields. Via a hydrogen autotransfer pathway, the reactions of primary alcohols with urea give tertiary amines exclusively, while secondary alcohols selectively afford secondary amines.
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Direct laser interference ablating nanostructures on organic crystals.
Opt Lett
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Two-beam interference ablation of 1,4-Bis(4-methylstyryl)benzene organic crystal by short laser pulses (10 ns, 355 nm) is presented. The influence of laser fluence, interference period, and pulse number on the morphology have been studied. The morphology is closely associated with the molecular interactions in the crystals, and it could be well controlled by adjusting the laser fluence and pulses number. Through interference ablating the crystals with high fluence pulses, and then treated with low fluence laser pulses, grating structures with smooth surface could be fabricated without any additional process.
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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.

How does it work?

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

Video X seems to be unrelated to Abstract Y...

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.