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Luster is a decorative metallic film that was applied on the surface of medieval glazed pottery. It can be obtained via the low-temperature (∼650°C), controlled reduction of copper and silver compounds. In this paper, we show that luster is a thin layered film (200–500 nm thick) that contains metallic spherical nanocrystals dispersed in a silicon-rich matrix and has a metal-free outermost glassy layer that is 10–20 nm thick. Silver nanocrystals seem to be separated from those of copper, forming aggregates 5–100 μm in diameter. This composite structure exhibits optical properties that are dependent on both the particle size and the matrix. Luster is indeed the first reproducible nanostructured thin metallic film that was made by humans.  相似文献   
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This article aims to prepare by injection molding recycled polymeric composites based on PA66 reinforced with short carbon fibers after artificial aging for applications in the automotive field. The aging cycles involves the combined action of UV radiation, moisture, and temperature in order to simulate the common outdoor conditions. The 100% recycled composites are obtained by the regranulation of the aged specimens followed by the remelting and re‐injection molding. The study is focused on the comparison between the mechanical behavior and the microstructure of the composites before and after mechanical recycling. The results of mechanical, thermal, and morphological investigations reveal that the recycling process had no significant effect on the final properties and microstructure of the recycled composites. Therefore the recycled PA66CF30 composites could be successfully used for structural or semi‐structural automotive applications guaranteeing good final performances and advantages from the environmental point of view. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42275.  相似文献   
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PURPOSE: To determine the treatment outcome of standard acute myeloid leukemia (AML)-type chemotherapy in a subset of patients with newly diagnosed myelodysplastic syndromes (MDS) compared with that of patients with de novo AML as defined using French-American-British (FAB) criteria. In addition, to determine the pretreatment variables having prognostic significance for treatment outcome in patients with MDS. PATIENTS AND METHODS: Nine hundred seven newly diagnosed patients with no history of cytopenias having a local institutional de novo AML successfully karyotyped and treated on Cancer and Leukemia Group B (CALGB) protocols for AML from 1984 to 1992. Thirty-three of the 907 patients were reclassified as having MDS on central pathology review using FAB criteria and form the basis of this analysis. RESULTS: The treatment outcomes for patients with MDS and AML were similar; the complete remission (CR) rate was 79% and 68%, respectively (P = .37); median CR duration was 11 and 15 months, respectively (P = .28); and median survival was 13 and 16 months, respectively (P = .72). For the MDS patients, there were no prognostic variables for CR rate identified. For CR duration, only the Sanz classification had prognostic value. The prognostic factors for survival in a univariate analysis included age, WBC count, Sanz classification, and percent blood blasts. In a proportional hazards analysis of survival, age greater than 60 years and WBC less than 2.6 x 10(9)/L were adverse prognostic factors. CONCLUSION: In patients with no known history of cytopenias who are treated intensively at diagnosis, the FAB distinctions between MDS (refractory anemia with excess blasts and refractory anemia with excess blasts in transformation) and AML appear to have little therapeutic relevance.  相似文献   
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The synthesis and the chemisorption from solution of a terbium bis‐phthalocyaninato complex suitable for the functionalization of lanthanum strontium manganite (LSMO) are reported. Two phosphonate groups are introduced in the double decker structure in order to allow the grafting to the ferromagnetic substrate actively used as injection electrode in organic spin valve devices. The covalent bonding of functionalized terbium bis‐phthalocyaninato system on LSMO surface preserves its molecular properties at the nanoscale. X‐ray photoelectron spectroscopy confirms the integrity of the molecules on the LSMO surface and a small magnetic hysteresis reminiscent of the typical single molecule magnet behavior of this system is detected on surface by X‐ray magnetic circular dichroism experiments. The effect of the hybrid magnetic electrode on spin polarized injection is investigated in vertical organic spin valve devices and compared to the behavior of similar spin valves embedding a single diamagnetic layer of alkyl phosphonate molecules analogously chemisorbed on LSMO. Magnetoresistance experiments have evidenced significant alterations of the magneto‐transport by the terbium bis‐phthalocyaninato complex characterized by two distinct temperature regimes, below and above 50 K, respectively.  相似文献   
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P2X7R-NLRP3 and AIM2 inflammasomes activate caspase-1 and the release of cytokines involved in viral-related liver disease. Little is known about their role in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steato-hepatitis (NASH). We characterized the role of inflammasomes in NAFLD, NASH, and HCV. Gene expression and subcellular localization of P2X7R/P2X4R-NLRP3 and AIM2 inflammasome components were examined in histopathological preparations of 46 patients with biopsy-proven viral and metabolic liver disease using real-time PCR and immunofluorescence. P2X7R, P2X4R, and Caspase-1 are two- to five-fold more expressed in patients with NAFLD/NASH associated with chronic HCV infection than those with metabolic damage only (p ≤ 0.01 for all comparisons). The AIM2 inflammasome is 4.4 times more expressed in patients with chronic HCV infection, regardless of coexistent metabolic abnormalities (p = 0.0006). IL-2, a cytokine playing a pivotal role during chronic HCV infection, showed a similar expression in HCV and NASH patients (p = 0.77) but was virtually absent in NAFLD. The P2X7R-NLRP3 complex prevailed in infiltrating macrophages, while AIM2 was localized in Kupffer cells. Caspase-1 expression correlated with elastography-based liver fibrosis (r = 0.35, p = 0.02), whereas P2X7R, P2X4R, NRLP3, Caspase-1, and IL-2 expression correlated with circulating markers of disease severity. P2X7R and P2X4R play a major role in liver inflammation accompanying chronic HCV infection, especially when combined with metabolic damage, while AIM2 is specifically expressed in chronic viral hepatitis. We describe for the first time the hepatic expression of IL-2 in NASH, so far considered a peculiarity of HCV-related liver damage.  相似文献   
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The aim of this study was to assess the diagnostic and prognostic value of the presence and characteristics of ischemic electrocardiographic (ECG) changes during dipyridamole stress echocardiography. The ECG response in 178 patients with echocardiographic evidence of myocardial ischemia during dipyridamole stress testing was analyzed. ECG changes occurred in 105 patients (59%). Patients with ECG changes had a higher incidence of echocardiographic signs of ischemia at a low dose than patients with an unchanged electrocardiogram (50% vs 23%; p = 0.0002). Three-vessel and/or left main coronary artery disease (CAD) was found in 41% of patients with and in 21% of patients without ECG changes (p = 0.029). During follow-up (33 +/- 19 months), 30 cardiac events occurred: 10 deaths, 6 infarctions, and 14 unstable anginas. Coronary revascularization was performed in 48 patients with and in 17 patients without ECG changes (p = 0.0022). The univariate predictors of cardiac events were: presence of ischemia in > or =4 ECG leads (p = 0.0004), echocardiographic evidence of ischemia at a low dose (p = 0.0062), ST-segment shift on precordial leads (p = 0.0094), family history of CAD (p = 0.0115), coexistence of > or =3 cardiovascular risk factors (p = 0.0156), ST-segment depression (p = 0.0172), and ECG changes during testing (p = 0.0335). At Cox analysis, occurrence of ischemia at a low dose (odds ratio 3.0; 95% confidence interval 1.3 to 6.8) and the presence of ischemia in > or =4 ECG leads (odds ratio 3.5; 95% confidence interval 1.3 to 9.3) had an independent prognostic importance. In conclusion, the presence and characteristics of ischemic ECG changes are associated with more extensive CAD and worse prognostic outlook than are echocardiographic changes alone during dipyridamole stress echocardiography.  相似文献   
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Very High-Speed True Random Noise Generator   总被引:1,自引:0,他引:1  
In this work an original CMOS implementation of a discrete-time deterministic-chaos algorithm for random bit generation is presented. The proposed circuit topology prevents the degradation of the generated-sequence statistical properties that can be caused by several factors, including the parameter spreading of the technological processes. Experimental results show that, with a final rate of 3 Mbit/s, the circuit is compliant with the most recent security requirements for cryptographic modules issued by the American National Institute of Standards and Technologies.  相似文献   
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