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21.
This article reports an exploratory user study in which a group of civil servants with experience of, or involvement in, intelligence analysis used the tool INVISQUE to address a problem using the 2011 VAST data set. INVISQUE uses a visual metaphor that combines searching, clustering, and sorting of document surrogates with free-form manipulation on an infinite canvas. The study looks into exposing the behaviors and related cognitive strategies that users would employ to better understand how this and similar environments might better support intelligence type work. The results include the observation that the search and spatial features of the system supported participants in establishing, elaborating, and systematically evaluating explanatory narratives that accounted for the data. Also, visual persistence at the interface allowed them to keep track of searches and to re-find documents when their importance became apparent. The article concludes with reflections on our findings and propose a set of guidelines for developing systems that support sensemaking.  相似文献   
22.
The demand for crocodile meat is quickly growing because of its exotic and organoleptic appeal and also the low content of cholesterol and lipids. Moreover, crocodile oil and blood have been used in alternative medicines for treating asthma and several other ailments since ancient times. Furthermore, crocodile hides have great demand in leather industries. All of these have collectively contributed to the extensive hunting, illegal trading and consequent decline of crocodiles in most parts of the world. To keep space with the growing demands, some crocodile species such as Crocodylus porosus have been raised in farms and its commercial trades have been legalised. However, demand for wild crocodiles in foods and medicines has continued in high gear. Recently, several DNA-based methods have been proposed for crocodile detection, but those assays are based on single gene and longer-sized amplicon targets that break down during extensive processing. To address this gap, here we developed and validated a highly stable double gene targeted multiplex PCR assay for the identification of C. porosus materials in commercial products. The assay involved two short sites from C. porosus atp6 (77 bp) and cytb (127 bp) genes and a universal internal control (99 bp) for eukaryotes. The PCR primers were cross-tested against 18 species and validated under pure and mixed matrices under extensive boiling, autoclaving and microwave cooking conditions. Finally, it was used to identify five crocodile-based commercial products. The lower limits of detection for atp6 and cytb genes were 0.001 ng and 0.01 ng DNA, respectively, in pure meat and 1% under mixed matrices. Some inherent features, such as 77–127 bp amplicon sizes, exceptional stability and superior sensitivity, suggested the assay could be used for the identification of C. porosus in any forensic specimen.  相似文献   
23.
This study drew on fairness theory and affective events theory to explain why individuals' emotional labor is impacted by injustice extended toward coworkers by their customers. Pairs of participants worked side by side as customer-service representatives for a simulated organization. They interacted with fair/unfair customers as well as observed face-to-face service encounters between their coworker and fair/unfair customers. Results indicated that participants' emotional labor increased both as a result of unfairness directed toward themselves as well as toward their coworkers. These effects were mediated by both discrete emotions and fairness-related counterfactual thinking and were significant even when the participants themselves had been treated fairly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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25.
Structurally similar double-point modified analogues of 1,25-dihydroxyvitamin D2 (1,25D2) were screened in vitro for their pro-differentiating activity against the promyeloid cell line HL60. Their affinities towards human full length vitamin D receptor (VDR) and metabolic stability against human vitamin D 24-hydroxylase (CYP24A1) were also tested. The analogues (PRI-1730, PRI-1731, PRI-1732, PRI-1733 and PRI-1734) contained 5,6-trans modification of the A-ring and of the triene system, additional hydroxyl or unsaturation at C-22 in the side chain and reversed absolute configuration (24-epi) at C-24 of 1,25D2. As presented in this paper, introduction of selected structural modifications simultaneously in two distinct parts of the vitamin D molecule resulted in a divergent group of analogues. Analogues showed lower VDR affinity in comparison to that of the parent hormones, 1,25D2 and 1,25D3, and they caused effective HL60 cell differentiation only at high concentrations of 100 nM and above. Unexpectedly, introducing of a 5,6-trans modification combined with C-22 hydroxyl and 24-epi configuration switched off entirely the cell differentiation activity of the analogue (PRI-1734). However, this analogue remained a moderate substrate for CYP24A1, as it was metabolized at 22%, compared to 35% for 1,25D2. Other analogues from this series were either less (12% for PRI-1731 and PRI-1733) or more (52% for PRI-1732) resistant to the enzymatic deactivation. Although the inactive analogue PRI-1734 failed to show VDR antagonism, when tested in HL60 cells, its structure might be a good starting point for our design of a vitamin D antagonist.  相似文献   
26.
The present work describes the synthesis and characterization of polyurethanamide/organo‐montmorillonite bio‐nanocomposites (OBNC) from Linseed oil‐a renewable resource. The aim of the work is (i) to widen the scope of application and improve the performance of vegetable oil based polymers, and (ii) to investigate the effect of introduction of modified clay on their structure, morphology, thermal stability, and coating properties. OBNC has been prepared by in situ polymerization of Linseed oil derived diol fattyamide and tolulylene‐2,4‐diisocyanate in the presence of different contents of OMMT (0.5–2.5 mass % in minimum amount of dimethylformamide) at room temperature. OBNC has been characterized by optical microscopy, FTIR, XRD, TEM, and TGA, which confirm the formation of OBNC. OBNC produced tough, scratch‐resistant, impact resistant, flexibility retentive coatings, which cure at room temperature with improved coating performance and thermal stability than virgin polymer. Amongst all the compositions, OMMT‐1.5 showed the best coating properties, with good scratch hardness (3.5 kg), impact (passes 200 lb/inch.) and bent test values (passes 1/8 inch). It can be commercially used as effective green coating material in future. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40278.  相似文献   
27.
The objective of this study is to assess the feasibility of solvent extraction (SE) for partial binder removal in the context of polymer co-extrusion with a thermoplastic binder component. Polymer co-extrusion is able to produce multilayered, functionally graded and/or textured structures in an efficient manufacturing process, but requires a polymer binder system with suitable flow characteristics. Traditionally, the binder is removed by thermal debinding (TD), which, however, is prone to form cracks or blisters, both of which are attributed to a lack of initial pore space that allows pyrolysis products to escape. The primary focus of this work is to demonstrate that a binder system with a high soluble binder content is suitable for conventional polymer co-extrusion and to document that a two-step binder removal process involving both SE and TD eliminates debinding defects. The overall fabrication process is documented for the extrusion of solid ceramic rods and co-extrusion of tubes, where alumina powder was batched with polyethylene butyl acrylate (PEBA) as backbone polymer and polyethylene glycol (PEG) as water soluble binder. SE for specimen with varying PEBA:PEG ratios was tested in water at three different temperatures for various times. The 1:1 mixture showed a PEG removal up to 80 wt.% of the original PEG content after 6 h extraction; after subsequent thermal debinding, rods and tubes sintered successfully without defects, demonstrating the viability of the process.  相似文献   
28.
Research efforts are being focused to develop polymers from bioresources such as plant oils from ecological and economical viewpoints, both in academic research and chemical industry worldwide. Plant oil polymers, their organic-inorganic hybrids and composites find versatile applications today. In the present work, we have reported the preparation and characterization of linseed oil based poly (ester urethane) metallohybrids [PEUMH] from linseed oil polyol [LPO], phthalic anhydride [PAN], toluylene-2,4-diisocyanate [TDI] as organic and copper (II) acetate [Cu-Ac] (in different amount) as inorganic precursors, respectively, in “one-pot, multi-step” reaction. PEUMH were characterized by spectral, physico-chemical, thermal (TGA and DSC) and morphological analyses by standard methods. The potentiality of the same as promising coating material was also evaluated. PEUMH are foreseen as prospective candidates for application as antibacterial self-sterilizing protective coatings due to oligodynamic effect of metal.  相似文献   
29.
This study investigates the potential of solid fuel blending as an effective approach to manipulate ash melting behaviour to alleviate ash-related problems during gasification, thus improving design, operabil-ity and safety. The ash fusion characteristics of Qinghai bituminous coal together with Fushun, Xinghua and Laoheishan oil shales (and their respective blends) were quantified using a novel picture analysis and graphing method, which incorporates conventional ash fusion study, dilatometry and sintering strength test, in a CO/CO2 atmosphere. This image-based characterisation method was used to monitor and quan-tify the complete melting behaviour of ash samples from room temperature to 1520 ℃. The impacts of blending on compositional changes during heating were determined experimentally via X-ray diffraction and validated computationally using FactSage. Results showed that the melting point of Qinghai coal ash to be the lowest at 1116 ℃, but would increase up to 1208 ℃, 1161 ℃ and 1160 ℃ with the addition of 30%–50% of Laoheishan, Fushun, and Xinghua oil shales, respectively. The formation of high-melting anorthite and mullite structures inhibits the formation of low-melting hercynite. However, the sintering point of Qinghai coal ash was seen to decrease from 1005 ℃ to 855 ℃, 834 ℃, and 819 ℃ in the same blends due to the formation of low-melting aluminosilicate. Results also showed that blending directly influences the sintering strength during the various stages of melting. The key finding from this study is that it is possible to mitigate against the severe ash slagging and fouling issue arising from high calcium and iron coals by co-gasification with a high silica-alumina oil shale. Moreover, blending coals with oil shales can also modify the ash melting behaviour of fuels to create the optimal ash chemistry that meets the design specification of the gasifier, without adversely affecting thermal performance.  相似文献   
30.
The migration behavior of heavy metal cations on cellulose layers using aqueous micellar, hydro-organic, and water-organic-surfactant mobile phases was investigated. Anionic, cationic, and nonionic surfactant systems were examined over a 0.001–5% concentration range. Brij-35, a nonionic surfactant capable of forming charged complexes with some metal ions, was identified as the best surfactant. The effect of the presence of organic additives, such as dimethylsulfoxide, dimethylformamide, methanol and acetone, on the mobility of metal ions was also studied. Acetone was found to be the most effective additive at 10% concentration with 3% Brij. Quantitative determination of UO2 2+ by spectrophotometry after preliminary thin-layer chromatographic (TLC) separation from Fe3+ and Hg2+ was also performed. A maximal recovery of 93% was obtained. This TLC method is rapid, with development times averaging 2 min.  相似文献   
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