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91.
Polyamide 6 (PA6) as a cost-effective polar polymer and barium titanate (BT) as piezoelectric ceramic nanofiller were melt compounded with poly(vinylidene fluoride) (PVDF) matrix to enhance the β electroactive phase. A series of samples with two blending ratios of PVDF/PA6 (90/10 and 70/30 [wt%/wt%]) each containing 1, 3, and 5 wt% of BT were prepared. The SEM results revealed that the addition of BT to the neat blends refined the biphasic morphology which is mainly due to selective localization of BTs in PA6 dispersed phase as confirmed by TEM observation and wetting parameter predictions. The EDX analysis demonstrated a uniform distribution of BT nanoparticles in the filled systems. FTIR and XRD results showed that β content increased as a result of blending while the α phase was suppressed. The BT nanoparticles inclusion to the blends showed a synergistic effect on the β-polymorph content. These results in combination with the data derived from DSC (indicating reduction of the total crystallinity) complement the idea of β enhancement by the addition of BT nanoparticles and PA6 into PVDF.  相似文献   
92.
Seed oil content of globe artichoke and its composition were assessed under three irrigation regimes, including irrigation at 20, 50, and 80 % depletion of soil available water. Water deficit affected the phenological characteristics, amount and the quality of the oil as well as the phenolics and antioxidant activity of the leaves and capitula. The seed oil content ranged from 18.7 % in 80 % to 22.8 % in 20 % treatment. The fatty acid composition of oil was determined using gas chromatography (GC). The predominant fatty acids in the oil were linoleic (51.68 %), oleic (34.22 %), palmitic (9.94 %), and stearic (3.58 %). Water deficit leads to reduced oil content, linoleic acid, the unsaturated/saturated fatty acid ratio and the iodine value. On the other hand, some other fatty acids such as palmitic and oleic acid and also the ratio of oleic/linoleic acid were elevated due to water deficit. Higher antioxidant activity was observed in capitula (IC50 = 222.6 μg ml?1) in comparison to the leaves (IC50 = 285.8 μg ml?1). Finally, the severe drought stress condition caused to gain higher oil stability, while the highest seed oil content and unsaturated fatty acids in the oil was obtained in non‐stress condition. Moreover, high phenolics, flavonoids and antioxidant activity as well as appreciable dry matter content were obtained in the moderate water stress condition.  相似文献   
93.
Bruton’s tyrosine kinase (BTK) and phosphoinositide 3-kinase (PI3K) in the B-cell receptor (BCR) signaling pathway are considered potential therapeutic targets for the treatment of B-cell lymphomas, among which, diffuse large B-cell lymphoma (DLBCL) is the most common type. Herein, we comparatively evaluated the single and combined application of the BTK inhibitor ibrutinib and the selective PI3Kγ inhibitor AS-605240 in the canine DLBCL cell line CLBL-1. For further comparison, key findings were additionally analyzed in canine B-cell leukemia GL-1 and human DLBCL cell line SU-DHL-4. While ibrutinib alone induced significant anti-proliferative effects on all cell lines in a dose-dependent manner, AS-605240 only induced anti-proliferative effects at high concentrations. Interestingly, ibrutinib and AS-605240 acted synergistically, reducing cell proliferation and increasing apoptosis/necrosis in all cell lines and inducing morphological changes in CLBL-1. Moreover, the combined application of ibrutinib and AS-605240 reduced relative phosphorylation and, in some instances, the levels of the BTK, AKT, GSK3β, and ERK proteins. Comparative variant analysis of RNA-seq data among canine B- and T-lymphoid cell lines and primary B-cell lymphoma samples revealed potentially high-impact somatic variants in the genes that encode PI3K, which may explain why AS-605240 does not singly inhibit the proliferation of cell lines. The combination of ibrutinib and AS-605240 represents a promising approach that warrants further in vivo evaluation in dogs, potentially bearing significant value for the treatment of human DLBCL.  相似文献   
94.
The rheology of non‐melt processible polytetrafluoroethylene (PTFE) pastes has been studied using a capillary rheometer. It was found that fibrils of submicron dimensions are created during PTFE paste processing, which are responsible for the final strength of the extrudate. The mechanism of fibrillation is explained in terms of the unwinding of crystallites. To describe the effects of die design, a simple mathematical model has been developed. The model takes into account the elastic‐plastic (strain hardening) and viscous nature of the material in its non‐melt state. The model predictions are found to be consistent with experimental results obtained from macroscopic pressure drop measurements and flow visualization experiments.  相似文献   
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In this work a self phase error compensating multiphase LC oscillator is proposed. Mismatches in LC tanks are considered as the main source of phase errors. Considering this, an analytical approach is proposed to find a relationship between phase errors and their corresponding coupling factors as a necessary condition for phase error cancellation then a self compensating circuit is proposed accordingly. The compensation circuit first detects the phase errors then employs them in a current tuner to change each stage coupling factor to reduce phase errors. The building blocks of the proposed circuit are investigated and the transistor level implementation of each one is presented afterwards. The theoretical results are evaluated and confirmed through simulations using ADS software in 0.18 μm CMOS technology. Simulation results show that not only phase errors are reduced with respect to the previous methods but also this procedure does not impose any further power consumption and phase noise to the circuit.  相似文献   
99.
We investigate economics PhDs minted at German, Austrian, and Swiss universities from 1991 to 2008. We find that cohort sizes increased overall, and the share of PhDs who publish in a peer-reviewed journal within 6 years after graduation increased from 18% in 1991 to 46% in 2008. Publishing rates are heterogeneous across departments. Younger cohorts publish slightly more compared to older cohorts, but these publications are not significantly better in terms of quality. Publication productivity is highly skewed within and between departments. A key difference between PhDs of the German-speaking area and North America lies in their patterns of collaboration.  相似文献   
100.
We show that an analogue of the ball-box theorem holds true for a class of corank 1, non-differentiable tangent subbundles that satisfy a geometric condition. We also we give examples of such bundles and give an application to dynamical systems.  相似文献   
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