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Find video protocols related to scientific articles indexed in Pubmed.
A Chemical Tuned Strategy to Develop Novel Irreversible EGFR-TK Inhibitors with Improved Safety and Pharmacokinetic Profiles.
J. Med. Chem.
PUBLISHED: 11-20-2014
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Gatekeeper T790M mutation in EGFR is the most prevalent factor underlying acquired resistance. Acrylamide-bearing quinazoline derivatives are powerful irreversible inhibitors for overcoming resistance. Nevertheless, concerns about the risk of non-specific covalent modification have motivated the development of novel cysteine-targeting inhibitors. In this paper, we demonstrate that fluoro-substituted olefins can be tuned to alter Michael addition reactivity. Incorporation of these olefins into the quinazoline templates produced potent EGFR inhibitors with improved safety and pharmacokinetic properties. A lead compound 5a was validated against EGFRWT, EGFR T790M as well as A431 and H1975 cancer cell lines. Additionally, compound 5a displayed a weaker inhibition against the EGFR-independent cancer cell line SW620 when compared withafatinib. Oral administration of 5a at a dose of 30mg/kg induced tumor regression in a murine-EGFRL858R/T790M driven H1975 xenograft model. Also, 5a exhibited improved oral bioavailability and safety, as well as favorable tissue distribution properties and enhanced brain uptake. These findings provide the basis of a promising strategy toward the treatment of NSCLC patients with drug resistance.
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Iterative dual energy material decomposition from spatial mismatched raw data sets.
J Xray Sci Technol
PUBLISHED: 11-20-2014
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Today's clinical dual energy computed tomography (DECT) scanners generally measure different rays for different energy spectra and acquire spatial mismatched raw data sets. The deficits in clinical DECT technologies suggest that mainly image based material decomposition methods are in use nowadays. However, the image based material decomposition is an approximate technique, and beam hardening artifacts remain in decomposition results. A recently developed image based iterative method for material decomposition from inconsistent rays (MDIR) can achieve much better image quality than the conventional image based methods. Inspired by the MDIR method, this paper proposes an iterative method to indirectly perform raw data based DECT even with completely mismatched raw data sets. The iterative process is initialized by density images that were obtained from an image based material decomposition. Then the density images are iteratively corrected by comparing the estimated polychromatic projections and the measured polychromatic projections. Only three iterations of the method are sufficient to greatly improve the qualitative and quantitative information in material density images. Compared with the MDIR method, the proposed method needs not to perform additional water precorrection. The advantages of the method are verified with numerical experiments from inconsistent noise free and noisy raw data.
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Tuning intramolecular electron and energy transfer processes in novel conjugates of La2@C80 and electron accepting subphthalocyanines.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
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A series of two conjugates with La2@C80 and subphthalocyanine (SubPc) have been prepared and characterized by means of cyclic voltammetry, absorption, fluorescence, and femtosecond resolved transient absorption spectroscopy. The strong electron-donating character of La2@C80 is essential to power an intramolecular electron-transfer in the La2@C80-SubPc conjugates upon photoexcitation.
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Autostereoscopy-based three-dimensional on-machine measuring system for micro-structured surfaces.
Opt Express
PUBLISHED: 11-18-2014
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Traditional off-line measuring systems find it difficult to measure micro-structured workpieces which have a large volume and heavy weight, such as micro-structured patterned precision roller drums. This paper proposes an autostereoscopy-based three-dimensional (3D) measuring method and develops an innovative measuring system for the 3D on-machine measurement of the micro-structured surfaces, an Autostereoscopy-based Three-Dimensional On-machine Measuring (ATDOM) system. The ATDOM system is compact and capable of fast data acquisition and high accuracy in 3D computational reconstruction of complex surfaces under different measuring environments. A prototype ATDOM system is experimentally verified through a series of measurement experiments conducted on a precision machine tool. The results indicate that the ATDOM system provides an important means for efficient and reliable on-machine measurement of micro-structured surfaces.
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Temporal changes in soil bacterial and archaeal communities with different fertilizers in tea orchards.
J Zhejiang Univ Sci B
PUBLISHED: 11-05-2014
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It is important to understand the effects of temporal changes in microbial communities in the acidic soils of tea orchards with different fertilizers. A field experiment involving organic fertilizer (OF), chemical fertilizer (CF), and unfertilized control (CK) treatments was arranged to analyze the temporal changes in the bacterial and archaeal communities at bimonthly intervals based on the 16S ribosomal RNA (rRNA) gene using terminal restriction fragment length polymorphism (T-RFLP) profiling. The abundances of total bacteria, total archaea, and selected functional genes (bacterial and archaeal amoA, bacterial narG, nirK, nirS, and nosZ) were determined by quantitative polymerase chain reaction (qPCR). The results indicate that the structures of bacterial and archaeal communities varied significantly with time and fertilization based on changes in the relative abundance of dominant T-RFs. The abundancy of the detected genes changed with time. The total bacteria, total archaea, and archaeal amoA were less abundant in July. The bacterial amoA and denitrifying genes were less abundant in September, except the nirK gene. The OF treatment increased the abundance of the observed genes, while the CF treatment had little influence on them. The soil temperature significantly affected the bacterial and archaeal community structures. The soil moisture was significantly correlated with the abundance of denitrifying genes. Of the soil chemical properties, soil organic carbon was the most important factor and was significantly correlated with the abundance of the detected genes, except the nirK gene. Overall, this study demonstrated the effects of both temporal alteration and organic fertilizer on the structures of microbial communities and the abundance of genes involved in the nitrogen cycle.
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Synthesis and Photophysical Properties of a Sc3 N@C80 -Corrole Electron Donor-Acceptor Conjugate.
Chemistry
PUBLISHED: 10-09-2014
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Embedding endohdedral metallofullerenes (EMFs) into electron donor-acceptor systems is still a challenging task owing to their limited quantities and their still largely unexplored chemical properties. In this study, we have performed a 1,3-dipolar cycloaddition reaction of a corrole-based precursor with Sc3 N@C80 to regioselectively form a [5,6]-adduct (1). The successful attachment of the corrole moiety was confirmed by mass spectrometry. In the electronic ground state, absorption spectra suggest sizeable electronic communications between the electron acceptor and the electron donor. Moreover, the addition pattern occurring at a [5,6]-bond junction is firmly proven by NMR spectroscopy and electrochemical investigations performed with 1. In the electronically excited state, which is probed in photophysical assays with 1, a fast electron-transfer yields the radical ion pair state consisting of the one-electron-reduced Sc3 N@C80 and of the one-electron-oxidized corrole upon its exclusive photoexcitation. As such, our results shed new light on the practical work utilizing EMFs as building blocks in photovoltaics.
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Highly regioselective 1,3-dipolar cycloaddition of diphenylnitrilimine to Sc3N@I(h)-C80 affording a very stable, unprecedented pyrazole-ring fused derivative of endohedral metallofullerenes.
Chem. Commun. (Camb.)
PUBLISHED: 09-09-2014
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Formation of a very stable, unprecedented pyrazole-ring fused derivative of endohedral metallofullerenes was achieved by the first 1,3-dipolar cycloaddition reaction of Sc3N@C80 with diphenylnitrilimine in a highly regioselective manner.
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Zebrafish Abcb4 is a potential efflux transporter of microcystin-LR.
Comp. Biochem. Physiol. C Toxicol. Pharmacol.
PUBLISHED: 09-01-2014
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Microcystin-LR (MC-LR) is one of the most common microcystins (MCs), which are hepatotoxic and released into a water body during a period of cyanobacterial blooms. These toxicants can be accumulated in aquatic animals and transferred along the food chain and thus pose adverse effects on aquatic environment and public health. Zebrafish Abcb4 is reported to mediate the cellular efflux of ecotoxicologically relevant compounds including galaxolide, tonalide and phenanthrene; however, it remains unclear whether Abcb4 functions in the detoxification of MC-LR. Here, we demonstrated the role of zebrafish Abcb4 in cellular efflux of MC-LR. Transcripts of zebrafish abcb4 were detected in all of adult tissues examined. MC-LR was able to induce the expression of abcb4 gene and overexpression of Abcb4 significantly decreased the cytotoxicity and accumulation of MC-LR in LLC-PK1 cells and developing embryos. In contrast, overexpression of an Abcb4-G1177D mutant abolished its transporter function but not substrate binding activity, and sensitized LLC-PK1 cells and developing embryos to this cyanobacterial toxin. Moreover, ATPase activity in developing embryos can be induced by MC-LR. Thus, zebrafish Abcb4 plays crucial roles in cellular efflux of MC-LR and is a potential molecular marker for the monitoring of cyanobacteria contamination in the aquatic environment.
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Male mate recognition via cuticular hydrocarbons facilitates sexual isolation between sympatric leaf beetle sister species.
J. Insect Physiol.
PUBLISHED: 08-27-2014
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Chemical signals in insects have been documented to play an important role in mate recognition, and divergence in chemical signals can often cause sexual isolation between closely related species or populations within species. We investigated the role of cuticular hydrocarbons (CHCs), short distance chemical signals, in male mate recognition between the two sympatric elm leaf beetles, Pyrrhalta maculicollis and Pyrrhaltaaenescens. Mating experiments demonstrated that strong sexual isolation between the two species was driven by CHCs divergence. Males preferred to mate with conspecific females with intact conspecific CHCs or conspecific CHCs reapplied after removal. Males also preferred heterospecific females that were treated with conspecific CHCs. Chemical analysis showed that the CHC profiles differ significantly between species. In P. maculicollis dimethyl-branched alkanes between C29 and C35 account for the majority of the saturated alkanes while the CHC profile of P. aenescens mostly consisted of monomethyl-branched alkanes between C22 and C29. Additionally, some compounds, such as 12,18-diMeC32, 12,18-diMeC34, are unique to P. maculicollis.
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Recent progress in the chemistry of endohedral metallofullerenes.
Chem. Commun. (Camb.)
PUBLISHED: 08-16-2014
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Putting metal atoms or metallic clusters into fullerenes has generated a new class of hybrid molecules, defined as endohedral metallofullerenes (EMFs), possessing novel structures and fascinating properties which are different from those of empty fullerenes. In particular, it has been revealed that the chemical properties of the cage carbons of EMFs depend strongly on the nature of the internal metallic species, such as their electronic configuration, location and even motion. Since the first report describing the successful derivatization of La@C82 in 1995, great efforts have been devoted to the chemical modification of EMFs during the last two decades. Although earlier studies mainly focused on readily available species such as M@C82, M2@C80 and M3N@C80 and the related results have been systematically summarized in our previous review paper (Chem. Commun., 2011, 47, 5942-5957), recent concerns about some relatively rare EMFs have developed rapidly. Moreover, taking advantage of single crystal X-ray crystallography, we can now clearly demonstrate the mutual influences between the internal metallic species and the chemical behaviours of the surrounding cage carbons, and the addends as well. In this article, we present recent achievements in the chemical functionalization of EMFs, which were mainly published during the last four years. For consistency, we will still pay special attention to the role that the metals play in controlling the properties of the whole EMF molecules. In this review, however, we will not only focus on concrete experimental results such as X-ray crystallographic and NMR spectroscopic data but will also include computational studies which have indeed enhanced our understanding of the chemical properties of EMFs. Applicable materials based on EMFs are also mentioned but are not discussed in detail.
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Robust reverse engineering of dynamic gene networks under sample size heterogeneity.
Pac Symp Biocomput
PUBLISHED: 08-15-2014
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Simultaneously reverse engineering a collection of condition-specific gene networks from gene expression microarray data to uncover dynamic mechanisms is a key challenge in systems biology. However, existing methods for this task are very sensitive to variations in the size of the microarray samples across different biological conditions (which we term sample size heterogeneity in network reconstruction), and can potentially produce misleading results that can lead to incorrect biological interpretation. In this work, we develop a more robust framework that addresses this novel problem. Just like microarray measurements across conditions must undergo proper normalization on their magnitudes before entering subsequent analysis, we argue that networks across conditions also need to be "normalized" on their density when they are constructed, and we provide an algorithm that allows such normalization to be facilitated while estimating the networks. We show the quantitative advantages of our approach on synthetic and real data. Our analysis of a hematopoietic stem cell dataset reveals interesting results, some of which are confirmed by previously validated results.
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Tuning gelation kinetics and mechanical rigidity of ?-hairpin peptide hydrogels via hydrophobic amino acid substitutions.
ACS Appl Mater Interfaces
PUBLISHED: 08-08-2014
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Self-assembling peptide hydrogels with faster gelation kinetics and higher mechanical rigidity are favorable for their practical applications. A design strategy to control the folding, self-assembly, and hydrogelation of ?-hairpin peptides via hydrophobic amino acid substitutions has been explored in this study. Isoleucine has higher hydrophobicity and stronger propensity for ?-sheet hydrogen bonding than valine. After the valine residues of MAX1 (VKVKVKVKV(D)PPTKVKVKVKV-NH2) were replaced with isoleucines, oscillatory rheometry and circular dichroism (CD) spectroscopy characterizations indicated that the variants had clearly faster self-assembly and hydrogelation rates and that the resulting gels displayed higher mechanical stiffness. Transmission electron microscopy (TEM) indicated the parent MAX1 and its variants all formed networks of long and entangled fibrils with the similar diameters of ?3 nm, suggesting little effect of hydrophobic substitutions on the self-assembled morphology. The MAX1I8 (IKIKIKIKV(D)PPTKIKIKIKI-NH2) hydrogel showed the fastest gelation rate (within 5 min) and the highest gel rigidity with the series, supporting the homogeneous cell distribution within its 3D scaffold. In addition, the MAX1I8 hydrogel showed quick shear-thinning and rapid recovery upon cessation of shear strain, and the MTT and immunological assays indicated its low cytotoxicity and good biocompatibility. These features are highly attractive for its widespread use in 3D cell culturing and regenerative medical treatments.
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Multifunctional graphene quantum dots for simultaneous targeted cellular imaging and drug delivery.
Colloids Surf B Biointerfaces
PUBLISHED: 08-07-2014
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This study demonstrates that ligand-modified graphene quantum dots (GQDs) facilitate the simultaneous operation of multiple tasks without the need for external dyes. These tasks include selective cell labeling, targeted drug delivery, and real-time monitoring of cellular uptake. Folic acid (FA)-conjugated GQDs are synthesized and utilized to load the antitumor drug doxorubicin (DOX). The fabricated nanoassembly can unambiguously discriminate cancer cells from normal cells and efficiently deliver the drug to targeted cells. The inherent stable fluorescence of GQDs enables real-time monitoring of the cellular uptake of the DOX-GQD-FA nanoassembly and the consequent release of drugs. The nanoassembly is specifically internalized rapidly by HeLa cells via receptor-mediated endocytosis, whereas DOX release and accumulation are prolonged. In vitro toxicity data suggest that the DOX-GQD-FA nanoassembly can target HeLa cells differentially and efficiently while exhibiting significantly reduced cytotoxicity to non-target cells.
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Genetic variation in the tissue factor gene is associated with clinical outcome in severe sepsis patients.
Crit Care
PUBLISHED: 08-03-2014
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IntroductionActivation of inflammation and coagulation was closely related and mutually interdependent in sepsis. Tissue factor (TF) and its endogenous inhibitor, tissue factor pathway inhibitor (TFPI) was the main regulators of the initiation of coagulation process. Altered plasma levels of TF and TFPI have been related to worse outcome in sepsis. The objective of this study was to investigate whether single nucleotide polymorphisms (SNPs) in the TF and TFPI genes were associated with risk and outcome for patients with severe sepsis.MethodsSeventeen SNPs in TF and TFPI were genotyped in samples of sepsis (n =577) and severe sepsis patients (n =476), and tested for association in this case¿control collection. We then investigated correlation between the associated SNPs and the mRNA expression, and protein level of the corresponding gene. The mRNA levels of TF were determined using real-time quantitative reverse transcription-polymerase chain reaction and the soluble plasma levels of TF were measured using enzyme linked immunosorbent assay (ELISA) method.ResultsAssociation analysis revealed that three TF SNPs in perfect linkage disequilibrium, rs1361600, rs3917615 and rs958587, were significantly associated with outcome of severe sepsis. G allele frequency of rs1361600 in survivor patients was significantly higher than that in nonsurvivor severe sepsis patients (P =4.91¿×¿10¿5, odds ratio (OR) =0.48, 95% confidence interval (CI) 0.33 to 0.69). The association remained significant after adjustment for covariates in multiple logistic regression analysis and for multiple comparisons. Lipopolysaccharide-induced TF-mRNA expression levels in peripheral blood mononuclear cells from subjects carrying rs1361600 AG and GG genotypes, were significantly lower than those subjects carrying AA genotype (P =0.0012). Moreover, severe sepsis patients of GG and GA genotypes showed lower serum levels of TF than patients with AA genotype (P adj =0.02). The plasma levels of TF were also associated with outcome of severe sepsis patients (P adj =0.01). However, genotype and allele analyses did not show any significant difference between sepsis and severe sepsis patients.ConclusionsOur findings indicate that common genetic variation in TF was significantly associated with outcome of severe sepsis in Chinese Han population.
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Kernel methods for large-scale genomic data analysis.
Brief. Bioinformatics
PUBLISHED: 07-24-2014
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Machine learning, particularly kernel methods, has been demonstrated as a promising new tool to tackle the challenges imposed by today's explosive data growth in genomics. They provide a practical and principled approach to learning how a large number of genetic variants are associated with complex phenotypes, to help reveal the complexity in the relationship between the genetic markers and the outcome of interest. In this review, we highlight the potential key role it will have in modern genomic data processing, especially with regard to integration with classical methods for gene prioritizing, prediction and data fusion.
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An update to the taxonomy of the genus Gastroserica Brenske (Coleoptera, Scarabaeidae, Sericini).
Zookeys
PUBLISHED: 07-17-2014
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Based on the examination of newly collected material and additional specimens housed in Chinese collections, our knowledge of Gastroserica Brenske, 1897, is expanded. Here, seven new species are described, including habitus photographs and illustrations of the male genitalia: Gastroserica haoyui sp. n. (China: Zhejiang Prov.), G. fengduana sp. n. (China: Sichuan Prov.), G. wenzhui sp. n. (China: Guangxi Prov.), G. damingshanica sp. n. (from China: Guangxi Prov.), G. jinxiuensis sp. n. (China: Guangxi Prov.), G. liboensis sp. n. (China: Yunnan Prov.) and G. carolusi sp. n. (Laos). Additionally, we provide a distribution map of the new taxa and new distribution records of the known taxa.
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Regioselective synthesis and molecular structure of the first derivative of praseodymium-containing metallofullerenes.
Chem. Commun. (Camb.)
PUBLISHED: 07-16-2014
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Regioselective cycloaddition of adamantylidene carbene to Pr@C(2v)(9)-C82 affords the first derivative of praseodymium-containing metallofullerenes. Single-crystal X-ray crystallographic data in combination with theoretical studies demonstrate that the addition is dictated by the single metal ion encapsulated inside the fullerene cage.
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Regioselective benzyl radical addition to an open-shell cluster metallofullerene. Crystallographic studies of cocrystallized Sc3C2@Ih-C80 and its singly bonded derivative.
J. Am. Chem. Soc.
PUBLISHED: 07-14-2014
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The endohedral fullerene once erroneously identified as Sc3@C82 was recently shown to be Sc3C2@Ih-C80, the first example of an open-shell cluster metallofullerene. We herein report that benzyl bromide (1) reacts with Sc3C2@ Ih-C80 via a regioselective radical addition that affords only one isomer of the adduct Sc3C2@Ih-C80(CH2C6H5) (2) in high yield. An X-ray crystallographic study of 2 demonstrated that the benzyl moiety is singly bonded to the fullerene cage, which eliminates the paramagnetism of the endohedral in agreement with the ESR results. Interestingly, X-ray results further reveal that the 3-fold disordered Sc3C2 cluster adopts two different configurations inside the cage. These configurations represent the so-called "planar" form and the computationally predicted, but not crystallographically characterized, "trifoliate" form. It is noteworthy that this is the first crystallographic observation of the "trifoliate" form for the Sc3C2 cluster. In contrast, crystallographic investigation of a Sc3C2@Ih-C80/Ni(OEP) cocrystal, in which the endohedral persists in an open-shell structure with paramagnetism, indicates that only the former form occurs in pristine Sc3C2@ Ih-C80. These results demonstrate that the cluster configuration in EMFs is highly sensitive to the electronic structure, which is tunable by exohedral modification. In addition, the electrochemical behavior of Sc3C2@Ih-C80 has been markedly changed by the radical addition, but the absorption spectra of the pristine and the derivative are both featureless. These results suggest that the unpaired electron of Sc3C2@Ih-C80 is buried in the Sc3C2 cluster and does not affect the electronic configuration of the cage.
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Network analysis of breast cancer progression and reversal using a tree-evolving network algorithm.
PLoS Comput. Biol.
PUBLISHED: 07-01-2014
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The HMT3522 progression series of human breast cells have been used to discover how tissue architecture, microenvironment and signaling molecules affect breast cell growth and behaviors. However, much remains to be elucidated about malignant and phenotypic reversion behaviors of the HMT3522-T4-2 cells of this series. We employed a "pan-cell-state" strategy, and analyzed jointly microarray profiles obtained from different state-specific cell populations from this progression and reversion model of the breast cells using a tree-lineage multi-network inference algorithm, Treegl. We found that different breast cell states contain distinct gene networks. The network specific to non-malignant HMT3522-S1 cells is dominated by genes involved in normal processes, whereas the T4-2-specific network is enriched with cancer-related genes. The networks specific to various conditions of the reverted T4-2 cells are enriched with pathways suggestive of compensatory effects, consistent with clinical data showing patient resistance to anticancer drugs. We validated the findings using an external dataset, and showed that aberrant expression values of certain hubs in the identified networks are associated with poor clinical outcomes. Thus, analysis of various reversion conditions (including non-reverted) of HMT3522 cells using Treegl can be a good model system to study drug effects on breast cancer.
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Cyclooxygenase-2 promoter 765C increase of digestive tract cancer risk in the Chinese population: a meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 06-28-2014
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To evaluate relationship between the cyclooxygenase-2 promoter 765G/C polymorphism and digestive cancer risk in China.
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Morphology-tunable synthesis of ZnO nanoforest and its photoelectrochemical performance.
Nanoscale
PUBLISHED: 06-24-2014
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Understanding and manipulating synthesis reactions and crystal growth mechanisms are keys to designing and constructing the morphology and functional properties of advanced materials. Herein, the morphology-controlled synthesis of three-dimensional (3D) ZnO nanoforests is reported via a facile hydrothermal route. Specifically, the respective and synergistic influence of polyethylenimine (PEI) and ammonia on tuning the architecture of ZnO nanoforests is systematically studied. An in-depth understanding of the mechanism of hydrothermal growth is vital for advancing this facile approach and incorporating special 3D nanostructures into versatile nanomanufacturing. More importantly, its unique architectural characteristics endow the willow-like ZnO nanoforest with prominent photoelectrochemical water splitting performance, including small charge transfer resistance, long photoelectron lifetime, a high photocurrent density of 0.919 mA cm(-2) at +1.2 V (vs. Ag/AgCl), and more important, a high photoconversion efficiency of 0.299% at 0.89 V (vs. RHE), which leads the realm of homogeneous ZnO nanostructures. In all, it is expected that this work will open up an unprecedented avenue to govern desirable 3D ZnO nanostructures and broaden the application potentials of 3D nanotechnology.
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Identification of RECQ1-regulated transcriptome uncovers a role of RECQ1 in regulation of cancer cell migration and invasion.
Cell Cycle
PUBLISHED: 06-17-2014
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The RECQ protein family of helicases has critical roles in protecting and stabilizing the genome. Three of the 5 known members of the human RecQ family are genetically linked with cancer susceptibility syndromes, but the association of the most abundant human RecQ homolog, RECQ1, with cellular transformation is yet unclear. RECQ1 is overexpressed in a variety of human cancers, indicating oncogenic functions. Here, we assessed genome-wide changes in gene expression upon knockdown of RECQ1 in HeLa and MDA-MB-231 cells. Pathway analysis suggested that RECQ1 enhances the expression of multiple genes that play key roles in cell migration, invasion, and metastasis, including EZR, ITGA2, ITGA3, ITGB4, SMAD3, and TGFBR2. Consistent with these results, silencing RECQ1 significantly reduced cell migration and invasion. In comparison to genome-wide annotated promoter regions, the promoters of genes downregulated upon RECQ1 silencing were significantly enriched for a potential G4 DNA forming sequence motif. Chromatin immunoprecipitation assays demonstrated binding of RECQ1 to the G4 motifs in the promoters of select genes downregulated upon RECQ1 silencing. In breast cancer patients, the expression of a subset of RECQ1-activated genes positively correlated with RECQ1 expression. Moreover, high RECQ1 expression was associated with poor prognosis in breast cancer. Collectively, our findings identify a novel function of RECQ1 in gene regulation and indicate that RECQ1 contributes to tumor development and progression, in part, by regulating the expression of key genes that promote cancer cell migration, invasion and metastasis.
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Solid-phase methylamidation for sialoglycomics by MALDI-MS.
Anal Bioanal Chem
PUBLISHED: 06-13-2014
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Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been a major approach for glycan analysis. However, the preferential cleavage of the sialic acid moiety by in- and post-source decay influences the determination of sialylated glycans by MALDI-MS. Many chemical derivatization methods were introduced to stabilize the sialylated glycan during MALDI-MS. Among current derivatization methods, methylamidation is a promising means for simultaneous analysis of natural sialylated glycans regardless of their sialic acid linkage types. Here, a novel derivatization method was developed, in which proteins were conjugated on the solid-phase support in order to stabilize the sialic acids by methylamidation and to reduce sample loss and contamination during the derivatization process. This derivatization strategy was used to investigate N-glycans from fetuin, a glycoprotein containing different types of complex N-glycans. The developed method was also applied to the N-glycan profiling of human serum from patients and healthy volunteers. Results were consistent with N-glycan profiling by HPLC-fluorescence detection. This new method provided a sensitive, simple, and robust approach for profiling glycan structures of complex samples.
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Bilateral transfer for learning to control timing but not for learning to control fine force.
Percept Mot Skills
PUBLISHED: 06-06-2014
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This study examined the characteristics of bilateral transfer of learning to control timing and fine force from a dominant limb to a nondominant limb. 20 right-handed college students (12 women, 8 men; M age = 21.5 yr., SD = 2.3) learned a sequential task consisting of timing and force control. Each participant completed a pre-test of the task with both hands and then performed 100 practice trials with the dominant hand. A post-test was conducted 1 hr. later. The results showed that after training, participants learned to control the timing and force. Nevertheless, only the time-control learning was transferred to the untrained hand, whereas the force-control learning did not transfer to the untrained hand.
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Seroprevalence to avian influenza A(H7N9) virus among poultry workers and the general population in southern China: a longitudinal study.
Clin. Infect. Dis.
PUBLISHED: 05-27-2014
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Confirmed cases of avian influenza A(H7N9) virus infection in humans continue to occur in mainland China. Few confirmed cases have occurred in poultry workers despite potentially higher rates of exposure.
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Sc2@C66 revisited: an endohedral fullerene with scandium ions nestled within two unsaturated linear triquinanes.
J. Am. Chem. Soc.
PUBLISHED: 05-14-2014
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The geometries of fullerenes are governed by the isolated pentagon rule (IPR), which states that stable fullerenes have each of their 12 pentagons surrounded by five hexagons. At the dawn of fullerene science, it was widely believed that the IPR would also be applicable for endohedral fullerenes. In 2000, that idea was altered by the discovery of the first non-IPR fullerenes, Sc2@C66 and Sc3N@C68. The structural data for Sc2@C66 were interpreted to indicate the presence of a pair of doubly fused pentagons. However, that structure has remained a long-standing mystery, since it is thermodynamically unfavorable. Here, we demonstrate definitively that Sc2@C66 does not have the structure that was long believed to be but a brand new type. 2D NMR spectroscopic and single-crystal X-ray analyses disclose that Sc2@C66 has a C2v(4059)-C66 cage containing two sets of unsaturated linear triquinanes (ULTs), in which three pentagons abut one another and two scandium ions are located within the folds of each of the ULT units.
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Highly transparent and efficient counter electrode using SiO2/PEDOT-PSS composite for bifacial dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 05-14-2014
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A highly transparent and efficient counter electrode was facilely fabricated using SiO2/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) inorganic/organic composite and used in bifacial dye-sensitized solar cells (DSCs). The optical properties of SiO2/PEDOT-PSS electrode can be tailored by the blending amount of SiO2 and film thickness, and the incorporation of SiO2 in PEDOT-PSS provides better transmission in the long wavelength range. Meanwhile, the SiO2/PEDOT-PSS counter electrode shows a better electrochemical catalytic activity than PEDOT-PSS electrode for triiodide reduction, and the role of SiO2 in the catalytic process is investigated. The bifacial DSC with SiO2/PEDOT-PSS counter electrode achieves a high power conversion efficiency (PCE) of 4.61% under rear-side irradiation, which is about 83% of that obtained under front-side irradiation. Furthermore, the PCE of bifacial DSC can be significantly increased by adding a reflector to achieve bifacial irradiation, which is 39% higher than that under conventional front-side irradiation.
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Bottom-up synthesis of nitrogen-doped graphene sheets for ultrafast lithium storage.
Nanoscale
PUBLISHED: 04-30-2014
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A facile bottom-up strategy was developed to fabricate nitrogen-doped graphene sheets (NGSs) from glucose using a sacrificial template synthesis method. Three main types of nitrogen dopants (pyridinic, pyrrolic and graphitic nitrogens) were introduced into the graphene lattice, and an inimitable microporous structure of NGS with a high specific surface area of 504 m(2) g(-1) was obtained. Particularly, with hybrid features of lithium ion batteries and Faradic capacitors at a low rate and features of Faradic capacitors at a high rate, the NGS presents a superior lithium storage performance. During electrochemical cycling, the NGS electrode afforded an enhanced reversible capacity of 832.4 mA h g(-1) at 100 mA g(-1) and an excellent cycling stability of 750.7 mA h g(-1) after 108 discharge-charge cycles. Furthermore, an astonishing rate capability of 333 mA h g(-1) at 10,000 mA g(-1) and a high rate cycle performance of 280.6 mA h g(-1) even after 1200 cycles were also achieved, highlighting the significance of nitrogen doping on the maximum utilization of graphene-based materials for advanced lithium storage.
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Concise review: unraveling stem cell cocultures in regenerative medicine: which cell interactions steer cartilage regeneration and how?
Stem Cells Transl Med
PUBLISHED: 04-24-2014
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Cartilage damage and osteoarthritis (OA) impose an important burden on society, leaving both young, active patients and older patients disabled and affecting quality of life. In particular, cartilage injury not only imparts acute loss of function but also predisposes to OA. The increase in knowledge of the consequences of these diseases and the exponential growth in research of regenerative medicine have given rise to different treatment types. Of these, cell-based treatments are increasingly applied because they have the potential to regenerate cartilage, treat symptoms, and ultimately prevent or delay OA. Although these approaches give promising results, they require a costly in vitro cell culture procedure. The answer may lie in single-stage procedures that, by using cell combinations, render in vitro expansion redundant. In the last two decades, cocultures of cartilage cells and a variety of (mesenchymal) stem cells have shown promising results as different studies report cartilage regeneration in vitro and in vivo. However, there is considerable debate regarding the mechanisms and cellular interactions that lead to chondrogenesis in these models. This review, which included 52 papers, provides a systematic overview of the data presented in the literature and tries to elucidate the mechanisms that lead to chondrogenesis in stem cell cocultures with cartilage cells. It could serve as a basis for research groups and clinicians aiming at designing and implementing combined cellular technologies for single-stage cartilage repair and treatment or prevention of OA.
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RNA-Seq identifies key reproductive gene expression alterations in response to cadmium exposure.
Biomed Res Int
PUBLISHED: 04-14-2014
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Cadmium is a common toxicant that is detrimental to many tissues. Although a number of transcriptional signatures have been revealed in different tissues after cadmium treatment, the genes involved in the cadmium caused male reproductive toxicity, and the underlying molecular mechanism remains unclear. Here we observed that the mice treated with different amount of cadmium in their rodent chow for six months exhibited reduced serum testosterone. We then performed RNA-seq to comprehensively investigate the mice testicular transcriptome to further elucidate the mechanism. Our results showed that hundreds of genes expression altered significantly in response to cadmium treatment. In particular, we found several transcriptional signatures closely related to the biological processes of regulation of hormone, gamete generation, and sexual reproduction, respectively. The expression of several testosterone synthetic key enzyme genes, such as Star, Cyp11a1, and Cyp17a1, were inhibited by the cadmium exposure. For better understanding of the cadmium-mediated transcriptional regulatory mechanism of the genes, we computationally analyzed the transcription factors binding sites and the mircoRNAs targets of the differentially expressed genes. Our findings suggest that the reproductive toxicity by cadmium exposure is implicated in multiple layers of deregulation of several biological processes and transcriptional regulation in mice.
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Expression level of pluripotent genes in incomplete reprogramming.
Asian Pac J Trop Med
PUBLISHED: 04-10-2014
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To compare the expression levels of pluripotent genes among incomplete reprogrammed colonies and induced pluripotent stem cells (iPSCs), to explore the relationship between the expression of pluripotent genes and incomplete reprogramming.
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Voxel model for evaluation of a three-dimensional display and reconstruction in integral imaging.
Opt Lett
PUBLISHED: 04-02-2014
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An approximate voxel model for integral imaging is proposed by ray tracing. By analyzing the case of corresponding pixels overlapping completely and partially in the image space, the voxel is defined with an appropriate approximation, and the voxel size and its distribution feature in imaging space are derived. The model is verified in a reconstruction experiment of a resolution target and compared with the calculation result of an integral imaging display or reconstruction system. The proposed model is simple and easy to calculate and thus useful for the evaluation and optimization of integral imaging systems.
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Expression and polymorphisms of T cell immunoglobulin domain and mucin domain protein-1 in thymoma with or without myasthenia gravis.
Oncol Lett
PUBLISHED: 03-27-2014
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The present study aimed to investigate the expression and association of the single-nucleotide polymorphism (SNP) -1637A/G in the promoter region of the T cell immunoglobulin domain and mucin domain protein-1 (Tim-1) gene in patients diagnosed with thymoma with or without myasthenia gravis (MG). The expression of Tim-1 was detected using the streptavidin peroxidase immunohistochemical staining method on tissues obtained from thymoma patients with (n=58) and without (n=62) MG. The Tim-1 gene -1637A/G polymorphism was detected using the single allele-specific primer polymerase chain reaction. The positive rate of Tim-1 expression in thymoma patients with MG was 62.1% (32/58), which was significantly higher compared with that in thymoma patients without MG (33.9%, 21/62) (P=0.002). The genotype frequencies of GG, GA and AA in the -1637A/G polymorphism were 0.7931, 0.2069 and 0, respectively, in thymoma patients with MG, and 0.6129, 0.3871 and 0, respectively, in thymoma patients without MG. A significant difference in the genotypes between the thymoma patients with MG and those without MG was found (P=0.031). In addition, a significant difference in allele frequencies between thymoma patients with MG and those without MG (P=0.024) was observed. The high expression of Tim-1 in thymoma tissues may play an important role in the development of thymoma with MG. The -1637A/G polymorphism site of the promoter region in Tim-1 may be associated with thymoma with MG. These findings provide a basis for further genetic research of thymoma with MG.
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Mapping of hepatic expression quantitative trait loci (eQTLs) in a Han Chinese population.
J. Med. Genet.
PUBLISHED: 03-24-2014
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Elucidating the genetic basis underlying hepatic gene expression variability is of importance to understand the aetiology of the disease and variation in drug metabolism. To date, no genome-wide expression quantitative trait loci (eQTLs) analysis has been conducted in the Han Chinese population, the largest ethnic group in the world.
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A phase 1 clinical trial of vorinostat in combination with decitabine in patients with acute myeloid leukaemia or myelodysplastic syndrome.
Br. J. Haematol.
PUBLISHED: 03-19-2014
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Patients with acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS) may respond to treatment with epigenetic-modifying agents. Histone deacetylase inhibitors may synergize with hypomethylating agents. This phase 1 dose-escalation study was designed to determine the maximum tolerated dose, recommended phase 2 dose, safety and tolerability of vorinostat plus decitabine in patients with relapsed/refractory AML, newly-diagnosed AML, or intermediate- to high-grade MDS. Thirty-four patients received concurrent therapy with decitabine plus vorinostat and 37 received sequential therapy with decitabine followed by vorinostat. Twenty-nine patients had relapsed/refractory AML, 31 had untreated AML and 11 had MDS. The target maximum administered dose (MAD) of decitabine 20 mg/m(2) daily for 5 d plus vorinostat 400 mg/d for 14 d was achieved for concurrent and sequential schedules, with one dose-limiting toxicity (Grade 3 QTc prolongation) reported in the sequential arm. Common toxicities were haematological and gastrointestinal. Responses were observed more frequently at the MAD on the concurrent schedule compared with the sequential schedule in untreated AML (46% vs. 14%), relapsed/refractory AML (15% vs. 0%) and MDS (60% vs. 0%). Decitabine plus vorinostat given concurrently or sequentially appears to be safe and well-tolerated. Concurrent therapy shows promising clinical activity in AML or MDS, warranting further investigation.
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miR-141 is a key regulator of renal cell carcinoma proliferation and metastasis by controlling EphA2 expression.
Clin. Cancer Res.
PUBLISHED: 03-19-2014
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Although microRNAs (miRNA) have been revealed as crucial modulators of tumorigenesis, our understanding of their roles in renal cell carcinoma (RCC) is limited. Here we sought to identify human miRNAs that act as key regulators of renal carcinogenesis.
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Effects of sample selection bias on the accuracy of population structure and ancestry inference.
G3 (Bethesda)
PUBLISHED: 03-19-2014
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Population stratification is an important task in genetic analyses. It provides information about the ancestry of individuals and can be an important confounder in genome-wide association studies. Public genotyping projects have made a large number of datasets available for study. However, practical constraints dictate that of a geographical/ethnic population, only a small number of individuals are genotyped. The resulting data are a sample from the entire population. If the distribution of sample sizes is not representative of the populations being sampled, the accuracy of population stratification analyses of the data could be affected. We attempt to understand the effect of biased sampling on the accuracy of population structure analysis and individual ancestry recovery. We examined two commonly used methods for analyses of such datasets, ADMIXTURE and EIGENSOFT, and found that the accuracy of recovery of population structure is affected to a large extent by the sample used for analysis and how representative it is of the underlying populations. Using simulated data and real genotype data from cattle, we show that sample selection bias can affect the results of population structure analyses. We develop a mathematical framework for sample selection bias in models for population structure and also proposed a correction for sample selection bias using auxiliary information about the sample. We demonstrate that such a correction is effective in practice using simulated and real data.
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Primary study on the lesions and specific proteins in BEAS-2B cells induced with the 2009 A (H1N1) influenza virus.
Appl. Microbiol. Biotechnol.
PUBLISHED: 03-17-2014
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In order to investigate the lesions and proteins with differential expression in cells infected with the 2009 A (H1N1) virus and to determine the specific proteins involved in cell damage, the present study has been performed. BEAS-2B cells were infected with the 2009 A (H1N1) influenza virus or the seasonal H1N1 influenza virus for 12, 24, 48, and 72 h, and cell cycle and apoptosis were analyzed with flow cytometry. Total cellular proteins were extracted and underwent two-dimensional gel electrophoresis. The differentially expressed proteins underwent mass spectrometry for identification. The results showed that after 12 h, cells infected with the virus strain sourced from severe cases had the highest apoptosis rate (P?
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Characterizing the effect of temperature fluctuation on the incidence of malaria: an epidemiological study in south-west China using the varying coefficient distributed lag non-linear model.
Malar. J.
PUBLISHED: 03-09-2014
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Malaria transmission is strongly determined by the environmental temperature and the environment is rarely constant. Therefore, mosquitoes and parasites are not only exposed to the mean temperature, but also to daily temperature variation. Recently, both theoretical and laboratory work has shown, in addition to mean temperatures, daily fluctuations in temperature can affect essential mosquito and parasite traits that determine malaria transmission intensity. However, so far there is no epidemiological evidence at the population level to this problem.
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[Immunomodulatory effect of UC-MSC on function of immunocytes of rats with collagen type II induced arthritis].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 03-07-2014
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This study was purposed to observe the influence of umbilical cord mesenchymal stem cells (UC-MSC) on the peripheral blood CD4(+)CD25(+)regulatory T cells (Treg), Th17 cells and neutrophils in rats with collagen type II-induced arthritis(CIA), and to explore the regulating effect of UC-MSC transplantation on immunocyte subgroup. The rats wee divided into 3 groups: CIA group (model group), UC-MSC treated group and blank control group. The CIA rats were injected with UC-MSC via tail vein. The percentage of CD4(+)CD25(+) cells in peripheral blood and the expression of NCD11b on neutrophil surface in CIA rates was detected by flow cytometry (FCM), and the serum interleukin-17 (IL-17) was observed by enzyme-linked immunosorbent assay (ELISA). The results showed that the mean fluorescence intensity(MFI) of NCD11b and the level of IL-17 in the model group were significantly higher than those in the blank control group, and the ratio of CD4(+)CD25(+) cells were significantly lower (P < 0.05). The MIF of NCD11b and the level of IL-17 in the UC-MSC treated group were significantly lower than that in the model group (P < 0.05), while the proportion of CD4(+)CD25(+) Treg increased (P < 0.05). Since the fifth week, the above indicators in the UC-MSC group have almostly approached the control group. It is concluded that the UC-MSC can increase peripheral blood Treg proportion in CIA rat, inhibit the secretion of Th17 and the activity of neutrophils, reduce the immune inflammation reaction, decrease the release of proinflammatory factor, and induce immune reconstruction.
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Ovine model for auricular reconstruction: porous polyethylene implants.
Ann. Otol. Rhinol. Laryngol.
PUBLISHED: 02-28-2014
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We developed a large animal model for auricular reconstruction with engineered cartilage frameworks and evaluated the performance of porous polyethylene auricular implants in this model.
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Enhancing the stiffness of collagen hydrogels for delivery of encapsulated chondrocytes to articular lesions for cartilage regeneration.
J Biomed Mater Res A
PUBLISHED: 02-26-2014
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This study investigated a dual crosslinking paradigm, consisting of (a) photocrosslinking with Rose Bengal (RB) and green light followed by (b) chemical crosslinking with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), and N-hydroxysuccinimide (NHS) to enhance collagen gel stiffness. In group 1, 50 ?L collagen constructs of 2% (w/v) type I collagen containing 10 ?M RB were allowed to gel spontaneously at 37°C. In group 2, the spontaneous gels were exposed to green light (532 nm). In group 3, the photochemically crosslinked gels were subsequently treated with a 1-h exposure to 33 mM EDC/6 mM NHS. Samples (n?=?18) were subjected to 0.08% (w/v) collagenase digestion, and the storage modulus of samples was measured by rheometry. Viability of encapsulated chondrocytes was measured by live/dead assay. Chondrocytes were ?95% viable in all constructs at 10 days in vitro. Resistance to collagenase digestion increased as; spontaneous gels (2 h)?24 h). The storage modulus of dual-crosslinked constructs was increased 5-fold over both photocrosslinked and spontaneous gels. As the dual crosslinking paradigm did not reduce encapsulated chondrocyte viability, these crosslinked collagen hydrogels could be a useful tool for the practical delivery of encapsulated chondrocytes to articular defects. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014.
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Assortative mating between two sympatric closely-related specialists: inferred from molecular phylogenetic analysis and behavioral data.
Sci Rep
PUBLISHED: 02-18-2014
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Host plant shifting of phytophagous insects can lead to the formation of host associated differentiation and ultimately speciation. In some cases, host plant specificity alone acts as a nearly complete pre-mating isolating barrier among insect populations. We here test whether effective pre-mating isolation and host-independent behavioral isolation have evolved under the condition of extreme host specilization using two sympatric flea beetles with incomplete post-mating isolation under laboratory conditions. Phylogenetic analysis and coalescent simulation results showed that there is a limited interspecific gene flow, indicating effctive isolation between these species. Three types of mating tests in the absence of host plant cues showed that strong host-independent behavioral isolation has evolved between them. We conclude that almost perfect assortative mating between these two extreme host specialists results from a combination of reduced encounter rates due to differential host preference and strong sexual isolation.
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Overexpression of CyclinA2 ameliorates hypoxia-impaired proliferation of cardiomyocytes.
Exp Ther Med
PUBLISHED: 02-16-2014
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Hypoxia is a primary mediator for cell survival, and has been reported to inhibit cardiomyocyte proliferation in fetal and neonatal hearts. CyclinA2 is a key regulator of cell proliferation. Whether CyclinA2 affects cardiomyocyte proliferation in hypoxic conditions remains unexamined. This study was designed to investigate the roles of CyclinA2 expression on hypoxia-impaired cardiomyocyte proliferation. Cardiomyocytes were isolated from neonatal rats and randomly separated into six groups: Control, hypoxia, enhanced green fluorescent protein (EGFP)-Adv, EGFP-Ccna2, EGFP-Adv + hypoxia and EGFP-Ccna2 + hypoxia. The cells in the control group were cultured in a general cell incubator; the cells in the hypoxia group were placed in a hypoxic chamber for 12 h; the cells in the EGFP-Adv and EGFP-Ccna2 groups were separately transfected with EGFP-adenovirus capsids or EGFP-adenovirus capsids with CyclinA2 cDNA for 18 h, and then placed in a general incubator for an additional 12 h; the cells in the EGFP-Adv + hypoxia and EGFP-Ccna2 + hypoxia groups were separately transfected with EGFP-adenovirus capsids or EGFP-adenovirus capsids with CyclinA2 cDNA for 18 h, and then placed in a hypoxia chamber for an additional 12 h. CyclinA2 expression was measured using immunochemical staining and western blot analysis, and cardiomyocyte proliferation was measured using the cell counting kit 8. GFP fluorescence indicated a high transfection efficiency (>80%), and immunochemical staining showed that CyclinA2 was mainly distributed in the nucleus. CyclinA2 expression was downregulated following exposure to hypoxia for 12 h. Cardiomyocyte proliferation was also significantly decreased following exposure to hypoxia for 12 h. However, compared with the EGFP-Adv group, CyclinA2 expression and cardiomyocyte proliferation was markedly increased in the EGFP-Ccna2 group. Furthermore, compared with the EGFP-Adv + hypoxia group, CyclinA2 expression and cell proliferation were markedly increased in the EGFP-Ccna2 + hypoxia group. These findings indicate that CyclinA2 upregulation improves cardiomyocyte proliferation in hypoxic conditions.
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The temporal lagged association between meteorological factors and malaria in 30 counties in south-west China: a multilevel distributed lag non-linear analysis.
Malar. J.
PUBLISHED: 02-13-2014
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The association between malaria and meteorological factors is complex due to the lagged and non-linear pattern. Without fully considering these characteristics, existing studies usually concluded inconsistent findings. Investigating the lagged correlation pattern between malaria and climatic variables may improve the understanding of the association and generate possible better prediction models. This is especially beneficial to the south-west China, which is a high-incidence area in China.
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Regioselective electrosynthesis of rare 1,2,3,16-functionalized [60]fullerene derivatives.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 02-05-2014
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Fullerene derivatives with different addition patterns exhibit different physical, chemical, and biological properties, which are important for fullerene applications. Novel and rare 1,2,3,16-functionalized [60]fullerene derivatives having a five-membered heterocycle fused to a [5,6]-junction were obtained with high regioselectivity by electrochemical derivatization of a [60]fulleroindoline. The product structures were determined by spectroscopic data and single-crystal X-ray analysis. The obtained high regioselectivity was rationalized using theoretical calculations.
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Ammonia-oxidation as an engine to generate nitrous oxide in an intensively managed calcareous fluvo-aquic soil.
Sci Rep
PUBLISHED: 01-16-2014
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We combine field observations, microcosm, stoichiometry, and molecular and stable isotope techniques to quantify N2O generation processes in an intensively managed low carbon calcareous fluvo-aquic soil. All the evidence points to ammonia oxidation and linked nitrifier denitrification (ND) being the major processes generating N2O. When NH4(+)-based fertilizers are applied the soil will produce high N2O peaks which are inhibited almost completely by adding nitrification inhibitors. During ammonia oxidation with high NH4(+) concentrations (>80?mg N kg(-1)) the soil matrix will actively consume oxygen and accumulate high concentrations of NO2(-), leading to suboxic conditions inducing ND. Calculated N2O isotopomer data show that nitrification and ND accounted for 35-53% and 44-58% of total N2O emissions, respectively. We propose that slowing down nitrification and avoiding high ammonium concentrations in the soil matrix are important measures to reduce N2O emissions per unit of NH4(+)-based N input from this type of intensively managed soil globally.
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Synthesis of highly luminescent and biocompatible CdTe/CdS/ZnS quantum dots using microwave irradiation: a comparative study of different ligands.
Luminescence
PUBLISHED: 01-16-2014
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We compared the effects of several ligands frequently used in aqueous synthesis, including L-cysteine, L-cysteine hydrochloride, N-acetyl-L-cysteine (NAC), glutathione and 3-mercaptopropionic acid, for microwave synthesis of CdTe quantum dots (QDs) in a sealed vessel with varied temperatures and times, and then developed a rapid microwave-assisted protocol for preparing highly luminescent, photostable and biocompatible CdTe/CdS/ZnS core-multishell QDs. The effects of molecular structures of these ligands on QD synthesis under high temperatures were explored. Among these ligands, NAC was found to be the optimal ligand in terms of the optical properties of resultant QDs and reaction conditions. The emission wavelength of NAC-capped CdTe QDs could reach 700?nm in 5?min by controlling the reaction temperature, and the resultant CdTe/CdS/ZnS core-multishell QDs could achieve the highest quantum yields up to 74% with robust photostability. In addition, the effects of temperature, growth time and shell-precursor ratio on shell growth were examined. Finally, cell culturing indicated the low cytotoxicity of CdTe/CdS/ZnS core-multishell QDs as compared to CdTe and CdTe/CdS QDs, suggesting their high potential for applications in biomedical imaging and diagnostics. Copyright © 2014 John Wiley & Sons, Ltd.
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Characteristics of toxic metal accumulation in farmland in relation to long-term chicken manure application: a case study in the Yangtze River Delta Region, China.
Bull Environ Contam Toxicol
PUBLISHED: 01-10-2014
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Characteristics of toxic metal accumulation in farmland in relation to intensive chicken manure application on a regional scale was studied in this paper. Concentrations of Zn, As and Cu in manure exceeded the related standard in 66.7%, 14.3% and 16.7% of samples, respectively. Among chicken feed samples, concentrations of Zn, Cr and As exceeded the National Standard limits in 74.3%, 56.3% and 34.3% of samples, respectively. The accumulation of metals in soils from long-term chicken manure application has led to increasing uptake in above-ground shoots of wheat. The maximum contents of all metals present in the soil are currently below the threshold values of National Grade II criteria. At present, the farmland soil is safe for agricultural production, but more attention should be given to the potential environmental risk of metal accumulation in chicken manure and soils.
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Japanese encephalitis risk and contextual risk factors in southwest China: a Bayesian hierarchical spatial and spatiotemporal analysis.
Int J Environ Res Public Health
PUBLISHED: 01-09-2014
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It is valuable to study the spatiotemporal pattern of Japanese encephalitis (JE) and its association with the contextual risk factors in southwest China, which is the most endemic area in China. Using data from 2004 to 2009, we applied GISmapping and spatial autocorrelation analysis to analyze reported incidence data of JE in 438 counties in southwest China, finding that JE cases were not randomly distributed, and a Bayesian hierarchical spatiotemporal model identified the east part of southwest China as a high risk area. Meanwhile, the Bayesian hierarchical spatial model in 2006 demonstrated a statistically significant association between JE and the agricultural and climatic variables, including the proportion of rural population, the pig-to-human ratio, the monthly precipitation and the monthly mean minimum and maximum temperatures. Particular emphasis was placed on the time-lagged effect for climatic factors. The regression method and the Spearman correlation analysis both identified a two-month lag for the precipitation, while the regression method found a one-month lag for temperature. The results show that the high risk area in the east part of southwest China may be connected to the agricultural and climatic factors. The routine surveillance and the allocation of health resources should be given more attention in this area. Moreover, the meteorological variables might be considered as possible predictors of JE in southwest China.
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Neuromuscular ultrasound application to the electrodiagnostic evaluation of quadrilateral space syndrome.
PM R
PUBLISHED: 01-07-2014
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Quadrilateral space syndrome (QSS) is a rare neurovascular compression syndrome that results from the compression of the axillary nerve and posterior circumflex humeral artery in the quadrilateral space. Electromyography often is used to evaluate for the presence of neuropathic changes in the deltoid and teres minor in cases of suspected QSS. Needle examination of the teres minor may be challenging because of the muscle's small size and proximity to the infraspinatus. In cases in which patients are overweight or have significant teres minor atrophy, localization of the muscle through conventional methods may be extremely difficult. We present a case of an overweight man with posterior shoulder pain who was diagnosed with QSS via the use of a combination of ultrasound and electromyography.
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Associations between methylenetetrahydrofolate reductase polymorphisms and hepatocellular carcinoma risk in Chinese population.
Tumour Biol.
PUBLISHED: 01-03-2014
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Genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene are considered to have some influence on both folate metabolism and cancer risk. Previous studies on the associations of MTHFR genetic polymorphisms with hepatocellular carcinoma (HCC) risk in Chinese population reported inconsistent results. We performed this meta-analysis to comprehensively assess the associations. Finally, 12 individual case-control studies were included into the meta-analysis. There were seven studies (6,384 subjects) on the MTHFR C677T polymorphism and five studies (4,502 subjects) on the MTHFR A1298C polymorphism. Overall, MTHFR C677T polymorphism was significantly associated with susceptibility to HCC in Chinese population (T versus C, odds ratio (OR)?=?1.09, 95 % confidence interval (95% CI) 1.01-1.17; TT versus CC, OR?=?1.17, 95% CI 1.00-1.38; TT/CT versus CC, OR?=?1.12, 95% CI 1.00-1.26). MTHFR A1298C polymorphism was conversely associated with HCC risk in Chinese population (CC versus AA, OR?=?0.65, 95% CI 0.46-0.91; CC versus AA/AC, OR?=?0.64, 95% CI 0.46-0.90). The sensitivity analysis confirmed the reliability and stability of the meta-analysis. Thus, the findings from our meta-analysis support the associations of MTHFR C677T and A1298C polymorphisms with HCC risk in Chinese population.
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Diffusion of Lexical Change in Social Media.
PLoS ONE
PUBLISHED: 01-01-2014
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Computer-mediated communication is driving fundamental changes in the nature of written language. We investigate these changes by statistical analysis of a dataset comprising 107 million Twitter messages (authored by 2.7 million unique user accounts). Using a latent vector autoregressive model to aggregate across thousands of words, we identify high-level patterns in diffusion of linguistic change over the United States. Our model is robust to unpredictable changes in Twitter's sampling rate, and provides a probabilistic characterization of the relationship of macro-scale linguistic influence to a set of demographic and geographic predictors. The results of this analysis offer support for prior arguments that focus on geographical proximity and population size. However, demographic similarity - especially with regard to race - plays an even more central role, as cities with similar racial demographics are far more likely to share linguistic influence. Rather than moving towards a single unified "netspeak" dialect, language evolution in computer-mediated communication reproduces existing fault lines in spoken American English.
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A taxonomic review on the species of Tetraserica Ahrens, 2004, of China (Coleoptera, Scarabaeidae, Sericini).
Zookeys
PUBLISHED: 01-01-2014
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A review on the Chinese species of Tetraserica Ahrens, 2004, is presented. The lectotype of Tetrasericatonkinensis (Moser, 1908), comb. n. is designated. Twenty-nine new Tetraserica species are described from China and adjacent regions: Tetrasericaanhuaensis sp. n., Tetrasericachangjiangensis sp. n., Tetrasericachangshouensis sp. n., Tetrasericadamaidiensis sp. n., Tetrasericadaqingshanica sp. n., Tetrasericafikaceki sp. n., Tetrasericagraciliforceps sp. n., Tetrasericajinghongensis sp. n., Tetrasericaleishanica sp. n., Tetrasericaliangheensis sp. n., Tetrasericalinaoshanica sp. n., Tetrasericalongipenis sp. n., Tetrasericalongzhouensis sp. n., Tetrasericamaoershanensis sp. n., Tetrasericamengeana sp. n., Tetrasericamenglongensis sp. n., Tetrasericapingjiangensis sp. n., Tetrasericaruiliana sp. n., Tetrasericaruiliensis sp. n., Tetrasericasculptilis sp. n., Tetrasericashangsiensis sp. n., Tetrasericashunbiensis sp. n., Tetrasericasigulianshanica sp. n., Tetrasericatianchiensis sp. n., Tetrasericawandingensis sp. n., Tetrasericawangtongensis sp. n., Tetrasericaxichouensis sp. n., Tetrasericayaoanica sp. n., Tetrasericayaoquensis sp. n. A key to the Chinese Tetraserica species is given, species distribution as well as the habitus and male genitalia of all species are illustrated.
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A taxonomic revision of the Neoserica(sensu lato)calva group (Coleoptera, Scarabaeidae, Sericini).
Zookeys
PUBLISHED: 01-01-2014
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The species of the Neoserica(sensu lato)calva group are revised. Neosericacalva Frey, 1972, comb. n. is redescribed. Thirteen new species are described from China and South Korea: Neosericaailaoshanica sp. n., Neosericaanonyma sp. n., Neosericacalvoides sp. n., Neosericagulinqingensis sp. n., Neosericakoelkebecki sp. n., Neosericaliangi sp. n., Neosericaluxiensis sp. n., Neosericamenghaiensis sp. n., Neosericamengi sp. n., Neosericataipingensis sp. n., Neosericazheijangensis sp. n., Neosericazhibenshanica sp. n., and Neosericazongyuani sp. n. A key to Sericini genera with multilamellate antenna and species groups of Neoserica of mainland Asia as well as a key to species of the Neosericacalva group are provided. A map of species distribution is given, habitus and male genitalia are illustrated.
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A taxonomic revision of the Neoserica (sensu lato) pilosula group (Coleoptera, Scarabaeidae, Sericini).
Zookeys
PUBLISHED: 01-01-2014
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Nine new species of the Neoserica (sensu lato) pilosula Moser, 1915, group are described from China: Neoserica curvipenis sp. n., N. emeishanensis sp. n., N. lincangensis sp. n., N. ludingensis sp. n., N. lushuiana sp. n., N. rangshuiensis sp. n., N. shennongjiaensis sp. n., N. tianeana sp. n., and N. weibaoshanica sp. n. The lectotype of Neoserica pilosula Moser, 1915, is designated. Habitus and male genitalia are illustrated, a key to the species of the group and a map of species distribution are given.
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A taxonomic review of the Neoserica (sensu lato) abnormis group (Coleoptera, Scarabaeidae, Sericini).
Zookeys
PUBLISHED: 01-01-2014
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The present paper revises the species belonging to the Neoserica (sensu lato) abnormis group, so far known only with two nominal species. Twenty new species are herein described from Indochina and southern China: N. abnormoides sp. n. (Vietnam, China), N. allolaotica sp. n., N. namthaensis sp. n., N. simplicissima sp. n. (Laos), N. thailandensis sp. n. (Thailand), N. alloputaoana sp. n., N. kanphantensis sp. n., N. natmatoungensis sp. n., N. putaoana sp. n., N. taunggyiana sp. n. (Myanmar), N. lamellosa sp. n., N. tonkinea sp. n. (Vietnam), N. bairailingshanica sp. n., N. euyunnanica sp. n., N. huangi sp. n., N. jiangxiensis sp. n., N. trifida sp. n., N. yaoi sp. n., N. yingjiangensis sp. n. (China), N. cardamomensis sp. n. (Indochina and southern China). One new combination is established: Neoserica ponderosa Arrow, 1946, comb. n. The lectotypes of Neoserica abnormis Moser, 1908 and the taxonomically uncertain N. inclinata Brenske, 1898, which very likely also belongs to this species group, are designated herein. A key to the species and to species groups is given, the genitalia of all species including their habitus are illustrated. Maps of species distribution are included.
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GWAS in a box: statistical and visual analytics of structured associations via GenAMap.
PLoS ONE
PUBLISHED: 01-01-2014
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With the continuous improvement in genotyping and molecular phenotyping technology and the decreasing typing cost, it is expected that in a few years, more and more clinical studies of complex diseases will recruit thousands of individuals for pan-omic genetic association analyses. Hence, there is a great need for algorithms and software tools that could scale up to the whole omic level, integrate different omic data, leverage rich structure information, and be easily accessible to non-technical users. We present GenAMap, an interactive analytics software platform that 1) automates the execution of principled machine learning methods that detect genome- and phenome-wide associations among genotypes, gene expression data, and clinical or other macroscopic traits, and 2) provides new visualization tools specifically designed to aid in the exploration of association mapping results. Algorithmically, GenAMap is based on a new paradigm for GWAS and PheWAS analysis, termed structured association mapping, which leverages various structures in the omic data. We demonstrate the function of GenAMap via a case study of the Brem and Kruglyak yeast dataset, and then apply it on a comprehensive eQTL analysis of the NIH heterogeneous stock mice dataset and report some interesting findings. GenAMap is available from http://sailing.cs.cmu.edu/genamap.
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A taxonomic review of the Neoserica (sensu lato) septemlamellata group (Coleoptera, Scarabaeidae, Sericini).
Zookeys
PUBLISHED: 01-01-2014
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In the present paper the species belonging to the Neoserica (sensu lato) septemlamellata group, that included so far only four known species, are revised. Here we describe eleven new species originating mainly from Indochina and Southern China: N. daweishanica sp. n., N. gaoligongshanica sp. n., N. guangpingensis sp. n., N. igori sp. n., N. jiulongensis sp. n., N. plurilamellata sp. n., N. weishanica sp. n., N. yanzigouensis sp. n. (China) N. sapaensis sp. n. (China, Vietnam), N. bansongchana sp. n., N. takakuwai sp. n. (Laos). The lectotypes of Neoserica septemlamellata Brenske, 1898 and N. septemfoliata Moser, 1915 are designated. Keys to the species and species groups are given, the genitalia of all species and their habitus are illustrated and distribution maps are included.
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A novel hierarchical Pt- and FTO-free counter electrode for dye-sensitized solar cell.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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A novel hierarchical Pt- and FTO-free counter electrode (CE) for the dye-sensitized solar cell (DSSC) was prepared by spin coating the mixture of TiO2 nanoparticles and poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS) solution onto the glass substrate. Compared with traditional Pt/FTO CE, the cost of the new CE is dramatically reduced by the application of bilayer TiO2-PEDOT:PSS/PEDOT:PSS film and the glass substrate. The sheet resistance of this composite film is 35 ? sq(-1) and is low enough to be used as an electrode. The surface morphologies of TiO2-PEDOT:PSS layer and modified PEDOT:PSS layer were characterized by scanning electron microscope, which shows that the former had larger surface areas than the latter. Electrochemical impedance spectra and Tafel polarization curves prove that the catalytic activity of TiO2-PEDOT:PSS/PEDOT:PSS/glass CE is higher than that of PEDOT:PSS/FTO CE and is similar to Pt/FTO CE's. This new fabricated device with TiO2-PEDOT:PSS/PEDOT:PSS/glass CE achieves a high power conversion efficiency (PCE) of 4.67%, reaching 91.39% of DSSC with Pt/FTO CE (5.11%).
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Forecasting influenza epidemics from multi-stream surveillance data in a subtropical city of China.
PLoS ONE
PUBLISHED: 01-01-2014
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Influenza has been associated with heavy burden of mortality and morbidity in subtropical regions. However, timely forecast of influenza epidemic in these regions has been hindered by unclear seasonality of influenza viruses. In this study, we developed a forecasting model by integrating multiple sentinel surveillance data to predict influenza epidemics in a subtropical city Shenzhen, China.
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Load-insensitive temperature sensor based on azobenzene-chloroform-solution-filled microstructured optical fiber.
Opt Lett
PUBLISHED: 12-18-2013
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A solid-core microstructured optical fiber is infiltrated with the Dispersed Yellow 7 and chloroform mixture solution, resulting in the appearance of several transmission dips with different temperature and axial load responses. The temperature- and load-dependent spectral characteristics of these dips have been investigated and the experimental results indicate that they are pretty temperature-sensitive, but insensitive to the variation of applied axial load. Such a compact fiber-optic device with electric perturbation immunity could be employed for load-insensitive temperature sensing with high sensitivity.
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[A study on the veterinary antibiotics contamination in groundwater of Jiaxing].
Huan Jing Ke Xue
PUBLISHED: 12-03-2013
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Liquid chromatography and tandem mass (LC-MS/MS) followed with solid-phase extraction (SPE) was developed for simultaneously determining four classes (tetracyclines, quinolones, macrolides and sulfonamides) of ten commonly used veterinary antibiotics in groundwater of Jiaxing city, an important pig breeding base in the Yangtze River Delta region. Samples were taken from 10 typical rural river sections and 21 main urban river sections. Results revealed severe pollution existed in the rural river environment. The total concentration of ten antibiotics was as high as 65.6-467.0 ng x L(-1), among which tetracyclines and sulfonamides respectively ranged in 40.8-253.0 ng x L(-1) and undetected (nd)- 165.0 ng x L(-1), macrolides and quinolones respectively ranged in 3.1-14.68 ng x L(-1) and nd-14.54 ng x L(-1). By comparison, the pollution level in urban rivers was much lower. The total concentration of ten antibiotics ranged in 20.1 ng x L(-1) to 61.2 ng x L(-1), among with tetracyclines varied from undetected to 44.0 ng x L(-1), while sulfonamides, macrolides and quinolones were respectively below 2.7 ng x L(-1), 6.3 ng x L(-1) and 21.6 ng x L(-1).
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On the maximal size of large-average and ANOVA-fit submatrices in a Gaussian random matrix.
Bernoulli (Andover)
PUBLISHED: 11-07-2013
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We investigate the maximal size of distinguished submatrices of a Gaussian random matrix. Of interest are submatrices whose entries have an average greater than or equal to a positive constant, and submatrices whose entries are well fit by a two-way ANOVA model. We identify size thresholds and associated (asymptotic) probability bounds for both large-average and ANOVA-fit submatrices. Probability bounds are obtained when the matrix and submatrices of interest are square and, in rectangular cases, when the matrix and submatrices of interest have fixed aspect ratios. Our principal result is an almost sure interval concentration result for the size of large average submatrices in the square case.
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NP-MuScL: unsupervised global prediction of interaction networks from multiple data sources.
J. Comput. Biol.
PUBLISHED: 10-17-2013
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Inference of gene interaction networks from expression data usually focuses on either supervised or unsupervised edge prediction from a single data source. However, in many real world applications, multiple data sources, such as microarray and ISH (in situ hybridization) measurements of mRNA abundances, are available to offer multiview information about the same set of genes. We propose ISH to estimate a gene interaction network that is consistent with such multiple data sources, which are expected to reflect the same underlying relationships between the genes. NP-MuScL casts the network estimation problem as estimating the structure of a sparse undirected graphical model. We use the semiparametric Gaussian copula to model the distribution of the different data sources, with the different copulas sharing the same precision (i.e., inverse covariance) matrix, and we present an efficient algorithm to estimate such a model in the high-dimensional scenario. Results are reported on synthetic data, where NP-MuScL outperforms baseline algorithms significantly, even in the presence of noisy data sources. Experiments are also run on two real-world scenarios: two yeast microarray datasets and three Drosophila embryonic gene expression datasets, where NP-MuScL predicts a higher number of known gene interactions than existing techniques.
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[Effects of leflunomide on podocytes exposed to high glucose condition and its mechanism].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-16-2013
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To explore the protective effects of leflunomide (A771726) on the expression of podocalyxin, NF-?B and matrix metalloproteinase-9 (MMP-9) in podocytes exposed to high glucose environment and elucidate its mechanism.
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Can posterior dynamic stabilization reduce the risk of adjacent segment deterioration?
Turk Neurosurg
PUBLISHED: 10-09-2013
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The aim of this study was to systematically review the relevant literature to develop a benchmark for the incidence of adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis) following the posterior dynamic stabilization (PDS) procedure and to investigate whether conclusions can be made with regard to the isolated PDS procedure in reducing the risk of ASDeg and ASDis compared with fusion, and with regard to the role of additional PDS devices implanted adjacent to fusion in protecting from ASDeg and ASDis caused by the neighboring fusion. MATERIAL and
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High-dimensional feature selection by feature-wise kernelized lasso.
Neural Comput
PUBLISHED: 10-08-2013
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The goal of supervised feature selection is to find a subset of input features that are responsible for predicting output values. The least absolute shrinkage and selection operator (Lasso) allows computationally efficient feature selection based on linear dependency between input features and output values. In this letter, we consider a feature-wise kernelized Lasso for capturing nonlinear input-output dependency. We first show that with particular choices of kernel functions, nonredundant features with strong statistical dependence on output values can be found in terms of kernel-based independence measures such as the Hilbert-Schmidt independence criterion. We then show that the globally optimal solution can be efficiently computed; this makes the approach scalable to high-dimensional problems. The effectiveness of the proposed method is demonstrated through feature selection experiments for classification and regression with thousands of features.
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Soliton behavior for a generalized mixed nonlinear Schro?dinger model with N-fold Darboux transformation.
Chaos
PUBLISHED: 10-05-2013
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A spectral problem, the x-derivative part of which is a simple generalization of the standard Ablowitz-Kaup-Newell-Segur and Kaup-Newell spectral problems, is presented with its associated generalized mixed nonlinear Schro?dinger (GMNLS) model. The N-fold Darboux transformation with multi-parameters for the spectral problem is constructed with the help of gauge transformation. According to the Darboux transformation, the solution of the GMNLS model is reduced to solving a linear algebraic system and two first-order ordinary differential equations. As an example of application, we list the modulus formulae of the envelope one- and two-soliton solutions. Note that our model is a generalized one with the inclusion of four coefficients (a, b, c, and d), which involves abundant NLS-type models such as the standard cubic NLS equation, the Gerdjikov-Ivanov equation, the Chen-Lee-Liu equation, the Kaup-Newell equation, and the mixed NLS of Wadati and/or Kundu, among others.
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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.