104 research outputs found

    Origin Identification and Quantitative Analysis of Honeys by Nuclear Magnetic Resonance and Chemometric Techniques

    Get PDF
    The combination of H-1 NMR spectroscopy and multivariate statistical analysis has become a promising method for the discrimination of food origins. In this paper, this method has been successfully employed to analyze 70 Chinese honey samples from eight botanic origins, three geographical origins, and five production dates. Thirty-three components in honey samples were detected and identified from their H-1 NMR spectra, and 20 of them were accurately quantified by comparing their integral area with that of internal standards with relaxation time correction. Nontargeted principal component analysis (PCA) has been applied to distinguish the honeys from different botanical and geographical origins. The variations of components in the honeys, including saccharides and all kind of amino and organic carboxylic acids, confirmed their clustering according to their origins in PCA scores plots. Orthogonal partial least squares discriminant analysis (OPLS-DA) based on the NMR data for the different pairwise honey samples allows to identify the compositional variations contributed to geographical discrimination and storage time. Hence, NMR spectroscopy coupled with chemometric techniques offers an efficient tool for quality control of honey, and it could further serve to the classification, qualitative and quantitative control of other foods

    Proteomic responses reveal the differential effects induced by cadmium in mussels Mytilus galloprovincialis at early life stages

    Get PDF
    Cadmium (Cd) has become an important metal contaminant and posed severe risk on the organisms in the coastal environments of the Bohai Sea. Marine mussel Mytilus galloprovincialis is widely distributed along the Bohai coast and consumed as seafood by local residents. Evidences indicate that the early stages of marine organisms are more sensitive to metal contaminants. In this study, we applied two-dimensional electrophoresis-based proteomics to characterize the biological effects of Cd (50 mu g L-1) in the early life stages (D-shape larval and juvenile) of mussels. The different proteomic responses demonstrated the differential responsive mechanisms to Cd exposure in these two early life stages of mussels. In details, results indicated that Cd mainly induced immune and oxidative stresses in both D-shape larval and juvenile mussels via different pathways. In addition, the significant up-regulation of triosephosphate isomerase and metallothionein confirmed the enhanced energy demand and mobilized detoxification mechanism in D-shape larval mussels exposed to Cd. In juvenile mussels, Cd exposure also induced clear apoptosis. Overall, this work suggests that Cd is a potential immune toxicant to mussel M. galloprovincialis at early life stages. (C) 2016 Elsevier Ltd. All rights reserved

    Synthesis of thick Ni66Cr5Mo4Zr6P15B4 amorphous alloy coating and large glass-forming ability by laser cladding

    Get PDF
    A thick amorphous alloy (a-alloy) coating was synthesized by laser cladding. The a-alloy had a multicomponent chemistry, i.e., Ni66Cr5MO4Zr6P15B4 (in atom%). The maximum thickness of the coating is 0.8 mm. The a-alloy coating had large glass-forming ability (GFA) with wide supercooled liquid region (SLR) ranging from 52 to 61 K through the coating. The reason for high GFA in the a-alloy coating was discussed. (C) 2002 Published by Elsevier Science B.V

    Non-Gaussian statistics for the motion of self-propelled Janus particles: Experiment versus theory

    Get PDF
    Spherical Janus particles are one of the most prominent examples for active Brownian objects. Here, we study the diffusiophoretic motion of such microswimmers in experiment and in theory. Three stages are found: simple Brownian motion at short times, superdiffusion at intermediate times, and finally diffusive behavior again at long times. These three regimes observed in the experiments are compared with a theoretical model for the Langevin dynamics of self-propelled particles with coupled translational and rotational motion. Besides the mean square displacement also higher displacement moments are addressed. In particular, theoretical predictions regarding the non-Gaussian behavior of self-propelled particles are verified in the experiments. Furthermore, the full displacement probability distribution is analyzed, where in agreement with Brownian dynamics simulations either an extremely broadened peak or a pronounced double-peak structure is found, depending on the experimental conditions

    Pan-cancer analysis of whole genomes

    Get PDF
    Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

    El descanso del guerrero. Memoria visual del combatiente en Madrid, 1936-1939

    Get PDF
    Actas de las Quintas Jornadas Imagen, Cultura y Tecnología celebradas del 3 al 5 de julio de 2006 en la Universidad Carlos III de Madri

    People's commune 2.0 reconfiguration-developing a participatory strategy for upgrading Chinese post-Danwei community

    No full text
    A major feature of China’s urban transformation was the breakdown of the danwei system and the consequent efforts at community development and community building. Chinese post-danwei community has become a meeting ground for citizen activities, business organization involvement and party-state intervention. No longer just a supplementary institution in state control, Danwei has to confront the crisis in the spatial, economic, political and social transformation. In the process of the revitalization, there is the dilemma between grass roots democracy practices and top-down state governance. This thesis therefore is to research and design a participatory democratic community model within the conception of the People’s commune 2.0 configuration. And the people’s commune 2.0 configuration is more like a methodology of a community-participation approach, synthesized a participation & communication strategy with a network-governance tool and a user-co-creation platform as the carrier for actors engagement patterns and potential spatial interventions in accordance with the local needs and resources, which could respond to the pragmatic issues mentioned in this project, shifting the conflicts caused by the possible trend of danwei-community regeneration agenda in current municipality means of planning and governance to positive interaction among different actors, creating a win-win situation with the equilibrium on actors voices, expectations and value, and promote participatory democracy development in local community, thereby securing the position of the post-Danwei residents culturally, spatially and economically.We the people-democracy, architecture and cityUrbanismArchitectur

    Microstructual evolution of a dual phase steel during continuous annealing

    No full text
    With a combination of high strength and good formability, dual-phase steels have gained much interest in the automobile industry. The final microstructure, which leads to mechanical properties of the product, is strongly dependent on the processing of the steel. Apart from hot-rolling and cold-rolling, the parameters during continuous annealing are of great importance to control the properties of the final product. This thesis is aimed to study the influence of heating rates on the microstructual evolution of a DP-steel during continuous annealing lines. The microstructual evolution evolves several phenomena, such as ferrite recrystallization, pearlite degradation, and austenite phase transformation. Experimental approaches as dilatometry and SEM are used to investigate the evolution, by applying different heating rates and stop-quenching at different temperature and soaking times. Modelling approaches, CA-model and phase field model, are also introduced to provide a further insight into the phenomena.Mechanical, Maritime and Materials EngineeringMaterials Science and Engineering (MSE

    Performance assessment on high strength steel endplate connections after fire

    No full text
    Purpose – This study aims to reveal more information and understanding on performance and failure mechanisms of high strength steel endplate connections after fire. Design/methodology/approach – An experimental and numerical study on seven endplate connections after cooling down from fire temperature of 550°C has been carried out and reported herein. Moreover, the provisions of European design standard for steel structures, Eurocode 3, were validated with test results of high strength steel endplate connections. Findings – In endplate connections, a proper design using a thinner high strength steel endplate can achieve the same failure mode, similar residual load bearing capacity and comparable or even higher rotation capacity after cooling down from fire. It is found that high strength steel endplate connection can regain more than 90 per cent of its original load bearing capacity after cooling down from fire temperature of 550°C. Originality/value – The post-fire performance of high strength steel endplate connection has been reported. The accuracy of Eurocode 3 for endplate connections is validated against test results. Keywords Numerical study, Experimental study, High strength steel, After fire, Endplate connection Steel & Composite Structure

    Alternating optimization of design and stress for stress-constrained topology optimization

    No full text
    Handling stress constraints is an important topic in topology optimization. In this paper, we introduce an interpretation of stresses as optimization variables, leading to an augmented Lagrangian formulation. This formulation takes two sets of optimization variables, i.e., an auxiliary stress variable per element, in addition to a density variable as in conventional density-based approaches. The auxiliary stress is related to the actual stress (i.e., computed by its definition) by an equality constraint. When the equality constraint is strictly satisfied, an upper bound imposed on the auxiliary stress design variable equivalently applies to the actual stress. The equality constraint is incorporated into the objective function as linear and quadratic terms using an augmented Lagrangian form. We further show that this formulation is separable regarding its two sets of variables. This gives rise to an efficient augmented Lagrangian solver known as the alternating direction method of multipliers (ADMM). In each iteration, the density variables, auxiliary stress variables, and Lagrange multipliers are alternatingly updated. The introduction of auxiliary stress variables enlarges the search space. We demonstrate the effectiveness and efficiency of the proposed formulation and solution strategy using simple truss examples and a dozen of continuum structure optimization settings.Accepted Author ManuscriptMaterials and Manufacturin
    corecore