42 research outputs found

    Influence of reducing agents and surfactants on size and shape of silver fine powder particles

    Get PDF
    Silver fine powder with different shapes and sizes were prepared by chemical reduction and characterized by scanning electron microscope. In this paper was presented the method for the preparation of the fine Ag powder with particles size smaller than 2.5 µm with suitability for the mass-production scale. Reduction was performed from nitrate solution directly by vigorous stirring at room temperature by three different reduction agents, with and without presence of two dispersants. Scanning electron microscopy revealed the preferred size of the particles obtained in all experiments with aim of the protecting agent. Larger particles and wider size distribution were obtained without surfactants although with average size of about 1 µm and small quantity of larger clusters of primary particles that is out of the fine powder classification. High purity, 99.999%, of silver was obtained in every experiment.  http://dx.doi.org/10.5937/metmateng1402073

    Lymphoproliferative Lesions in Salivary Glands

    Get PDF

    Gratitude and hospitality: Tamil refugee employment in London and the conditional nature of integration

    Get PDF
    Healy, R. L. 2014. The definitive, peer-reviewed and edited version of this article is published in Environment and Planning A, 2014, 46(3), pp. 614-628, http:dx/doi.org/10.1068/a4655The policy of integration attempts to address different elements of exclusion, yet relatively little research has considered what integration means to the refugees themselves. This paper explores one key area for supporting integration: employment.ESRC PTA-030-2005-0082

    Stable population structure in Europe since the Iron Age, despite high mobility

    Get PDF
    Ancient DNA research in the past decade has revealed that European population structure changed dramatically in the prehistoric period (14,000–3000 years before present, YBP), reflecting the widespread introduction of Neolithic farmer and Bronze Age Steppe ancestries. However, little is known about how population structure changed from the historical period onward (3000 YBP - present). To address this, we collected whole genomes from 204 individuals from Europe and the Mediterranean, many of which are the first historical period genomes from their region (e.g. Armenia and France). We found that most regions show remarkable inter-individual heterogeneity. At least 7% of historical individuals carry ancestry uncommon in the region where they were sampled, some indicating cross-Mediterranean contacts. Despite this high level of mobility, overall population structure across western Eurasia is relatively stable through the historical period up to the present, mirroring geography. We show that, under standard population genetics models with local panmixia, the observed level of dispersal would lead to a collapse of population structure. Persistent population structure thus suggests a lower effective migration rate than indicated by the observed dispersal. We hypothesize that this phenomenon can be explained by extensive transient dispersal arising from drastically improved transportation networks and the Roman Empire’s mobilization of people for trade, labor, and military. This work highlights the utility of ancient DNA in elucidating finer scale human population dynamics in recent history

    Unlocking cancer glycomes from histopathological formalin-fixed and paraffin-embedded (FFPE) tissue microdissections

    Get PDF
    N- and O-glycans are attractive clinical biomarkers as glycosylation changes in response to diseases. The limited availability of defined clinical specimens impedes glyco-biomarker identification and validation in large patient cohorts. Formalin-fixed paraffin-embedded (FFPE) clinical specimens are the common form of sample preservation in clinical pathology, but qualitative and quantitative N- and O-glycomics of such samples has not been feasible to date. Here, we report a highly sensitive and glycan isomer selective method for simultaneous N- and O-glycomics from histopathological slides. As few as 2,000 cells isolated from FFPE tissue sections by laser capture microdissection were sufficient for in-depth histopathology-glycomics using porous graphitized carbon nanoLC ESI-MS/MS. N- and O-glycan profiles were similar between unstained and hematoxylin and eosin stained FFPE samples but differed slightly compared to fresh tissue. This method provides the key to unlock glyco-biomarker information from FFPE histopathological tissues archived in pathology laboratories worldwide

    Influence of reducing agents and surfactants on size and shape of silver fine powder particles

    Get PDF
    Silver fine powder with different shapes and sizes were prepared by chemical reduction and characterized by scanning electron microscope. In this paper was presented the method for the preparation of the fine Ag powder with particles size smaller than 2.5 µm with suitability for the mass-production scale. Reduction was performed from nitrate solution directly by vigorous stirring at room temperature by three different reduction agents, with and without presence of two dispersants. Scanning electron microscopy revealed the preferred size of the particles obtained in all experiments with aim of the protecting agent. Larger particles and wider size distribution were obtained without surfactants although with average size of about 1 µm and small quantity of larger clusters of primary particles that is out of the fine powder classification. High purity, 99.999%, of silver was obtained in every experiment

    Influence of reducing agents and surfactants on size and shape of silver fine powder particles

    No full text
    Silver fine powder with different shapes and sizes were prepared by chemical reduction and characterized by scanning electron microscope. In this paper was presented the method for the preparation of the fine Ag powder with particles size smaller than 2.5 µm with suitability for the mass-production scale. Reduction was performed from nitrate solution directly by vigorous stirring at room temperature by three different reduction agents, with and without presence of two dispersants. Scanning electron microscopy revealed the preferred size of the particles obtained in all experiments with aim of the protecting agent. Larger particles and wider size distribution were obtained without surfactants although with average size of about 1 µm and small quantity of larger clusters of primary particles that is out of the fine powder classification. High purity, 99.999%, of silver was obtained in every experiment
    corecore