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41.
Polymer blends were prepared in the whole composition range using polymers of different polarity. Mechanical properties were characterized by tensile measurements. Surface and interfacial properties were measured and calculated and parameters characterizing the miscibility were determined. A correlation was found between the yield stress and the thermodynamic quantities characterizing the degree of miscibility. Since both the degree of miscibility and morphology are influenced by the interfacial tension, it can be regarded as the best candidate to correlate polymer/polymer interaction and mechanical properties in polymer blends.  相似文献   
42.
The photocatalytic transformation of imazamox, a herbicide of imidazolinone family, is investigated in aqueous solution containing titanium dioxide, hydrogen peroxide or the combination of TiO2/H2O2 under simulated sunlight irradiation. The effect of parameters such as the amount of catalysts, the concentration of herbicide, and the pH were investigated by measurement of the rate constant of degradation. Experimental data obtained under different conditions describe the dependency of degradation rate on the above mentioned parameters. Consequently, kinetic parameters were experimentally determined and a pseudo-first-order kinetic was observed. Mulliken charge distributions calculated by the DFT method B3LYP/6–31+G(d) level of theory for key cationic, anionic and neutral structures of imazamox give interpretation for the dependency of photodegradation rate constant on pH. The degradation rate constants were always higher for the heterogeneous catalysis in reactions (TiO2/UV, TiO2/UV/H2O2) compared to the homogeneous systems (UV alone, H2O2/UV). In parallel, five photoproducts could be tentatively identified using Electrospray ionization Fourier transform ion cyclotron resonance mass spectroscopy based on precise chemical formula assignments.  相似文献   
43.
MatrixExplorer: a dual-representation system to explore social networks   总被引:3,自引:0,他引:3  
MatrixExplorer is a network visualization system that uses two representations: node-link diagrams and matrices. Its design comes from a list of requirements formalized after several interviews and a participatory design session conducted with social science researchers. Although matrices are commonly used in social networks analysis, very few systems support the matrix-based representations to visualize and analyze networks. MatrixExplorer provides several novel features to support the exploration of social networks with a matrix-based representation, in addition to the standard interactive filtering and clustering functions. It provides tools to reorder (layout) matrices, to annotate and compare findings across different layouts and find consensus among several clusterings. MatrixExplorer also supports node-link diagram views which are familiar to most users and remain a convenient way to publish or communicate exploration results. Matrix and node-link representations are kept synchronized at all stages of the exploration process  相似文献   
44.
We present the results of a user study that compares different ways of representing Dual-Scale data charts. Dual-Scale charts incorporate two different data resolutions into one chart in order to emphasize data in regions of interest or to enable the comparison of data from distant regions. While some design guidelines exist for these types of charts, there is currently little empirical evidence on which to base their design. We fill this gap by discussing the design space of Dual-Scale cartesian-coordinate charts and by experimentally comparing the performance of different chart types with respect to elementary graphical perception tasks such as comparing lengths and distances. Our study suggests that cut-out charts which include collocated full context and focus are the best alternative, and that superimposed charts in which focus and context overlap on top of each other should be avoided.  相似文献   
45.
Malignant mesenchymal tumors of the larynx constitute 0.3% to 1% of all laryngeal cancers, and of these osteosarcoma is the rarest. Our review of the literature identified only 12 cases of osteosarcoma of the larynx, all of which occurred in men. Rarely, osteosarcoma of the larynx may follow radiation therapy for squamous cell carcinoma, or the larynx may be the site of metastatic osteosarcoma. We report a case of primary laryngeal osteosarcoma arising in the cricoid cartilage and the first case of osteosarcoma of the larynx occurring in a woman.  相似文献   
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Antiviral type I interferons (IFN) produced in the early phase of viral infections effectively inhibit viral replication, prevent virus-mediated tissue damages and promote innate and adaptive immune responses that are all essential to the successful elimination of viruses. As professional type I IFN producing cells, plasmacytoid dendritic cells (pDC) have the ability to rapidly produce waste amounts of type I IFNs. Therefore, their low frequency, dysfunction or decreased capacity to produce type I IFNs might increase the risk of severe viral infections. In accordance with that, declined pDC numbers and delayed or inadequate type I IFN responses could be observed in patients with severe coronavirus disease (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as compared to individuals with mild or no symptoms. Thus, besides chronic diseases, all those conditions, which negatively affect the antiviral IFN responses lengthen the list of risk factors for severe COVID-19. In the current review, we would like to briefly discuss the role and dysregulation of pDC/type I IFN axis in COVID-19, and introduce those type I IFN-dependent factors, which account for an increased risk of COVID-19 severity and thus are responsible for the different magnitude of individual immune responses to SARS-CoV-2.  相似文献   
49.
Thyroid hormone (TH) signaling is a prerequisite of normal tissue function. Environmental pollutants with the potential to disrupt endocrine functions represent an emerging threat to human health and agricultural production. We used our Thyroid Hormone Action Indicator (THAI) mouse model to study the effects of tetrabromobisphenol A (TBBPA; 150 mg/bwkg/day orally for 6 days) and diclazuril (10.0 mg/bwkg/day orally for 5 days), a known and a potential hormone disruptor, respectively, on local TH economy. Tissue-specific changes of TH action were assessed in 90-day-old THAI mice by measuring the expression of a TH-responsive luciferase reporter in tissue samples and by in vivo imaging (14-day-long treatment accompanied with imaging on day 7, 14 and 21 from the first day of treatment) in live THAI mice. This was followed by promoter assays to elucidate the mechanism of the observed effects. TBBPA and diclazuril impacted TH action differently and tissue-specifically. TBBPA disrupted TH signaling in the bone and small intestine and impaired the global TH economy by decreasing the circulating free T4 levels. In the promoter assays, TBBPA showed a direct stimulatory effect on the hdio3 promoter, indicating a potential mechanism for silencing TH action. In contrast, diclazuril acted as a stimulator of TH action in the liver, skeletal muscle and brown adipose tissue without affecting the Hypothalamo-Pituitary-Thyroid axis. Our data demonstrate distinct and tissue-specific effects of TBBPA and diclazuril on local TH action and prove that the THAI mouse is a novel mammalian model to identify TH disruptors and their tissue-specific effects.  相似文献   
50.
In this article a trained sensory panel evaluated 6 flavored mineral water samples. The samples consisted of 3 different brands, each with 2 flavors (pear‐lemon grass and josta berry). The applied sensory method was profile analysis. Our aim was to analyze the sensory profiles and to investigate the similarities between the sensitivity of the trained human panel and an electronic tongue device. Another objective was to demonstrate the possibilities for the prediction of sensory attributes from electronic tongue measurements using a multivariate statistical method (Partial Least Squares regression [PLS]). The results showed that the products manufactured under different brand name but with the same aromas had very similar sensory profiles. The panel performance evaluation showed that it is appropriate (discrimination ability, repeatability, and panel consensus) to compare the panel's results with the results of the electronic tongue. The samples can be discriminated by the electronic tongue and an accurate classification model can be built. Principal Component Analysis BiPlot diagrams showed that Brand A and B were similar because the manufacturers use the same aroma brands for their products. It can be concluded that Brand C was quite different compared to the other samples independently of the aroma content. Based on the electronic tongue results good prediction models can be obtained with high correlation coefficient (r2 > 0.81) and low prediction error (RMSEP < 13.71 on the scale of the sensory evaluation from 0 to 100).  相似文献   
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