The dynamic interaction between precipitates and dislocations is a fundamental scientific principle for the precipitation hardening, which is hardly captured by post characterizations. In-situ ...tension experiments in transmission electron microscope (TEM) have been performed on the precipitation strengthened Cu-0.55 wt% Cr-0.05 wt% Zr alloy. The dynamic interaction between dislocations and Cr precipitates was recorded. The results showed that dislocations were pinned by the semi-coherent Cr precipitates and exhibited a typical intermittent gliding. The shearing mechanism was the prevalent one for the dislocations disengaging the Cr precipitates. The critical stress for shearing the Cr precipitates increased as the dislocations subsequently cut through the Cr precipitates. The in-situ tension technique in TEM could present a direct evidence of the deformation in the precipitation hardening alloys.
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•In-situ TEM tension tests of CuCrZr alloys were performed.•Dynamic interaction of dislocations and precipitates was revealed.•Dislocations were pinned by the semi-coherent Cr precipitates.•Dislocations exhibited an intermittent gliding behavior.
Abstract
Background
Most patients with ulcerative colitis (UC) rely predominantly on medication for disease control. Diet interventions can reduce pharmaceutical expenditures and prolong remission. ...We designed a prospective study to evaluate whether an immunoglobulin G (IgG)-guided exclusion diet would improve symptoms and quality of life (QoL) in patients with UC.
Methods
The 6-month diet intervention included 97 patients with UC, who were randomly divided into an intervention group (n = 49) and a control (n = 48) group. Individual diet plans were created for the intervention group according to IgG titers; the control group ate a healthy diet as normal. Observational indices included disease activity, extraintestinal manifestations, nutritional status, and QoL. Relationships between food-specific IgG antibodies and these indices were also analyzed.
Results
At baseline, there were no significant differences between the groups. Food-specific IgG antibodies were detected in 70.10% of participants. After intervention, the Mayo score was significantly lower in the intervention group than in the control group (2.41 ± 0.89 vs 3.52 ± 1.15, P < 0.05). The number of patients with extraintestinal manifestations decreased from 7 to 2 in the intervention group and from 6 to 5 in the control group. As for nutritive indices, the intervention group had higher mean body mass index and albumin than the control group (23.88 ± 3.31 vs 21.50 ± 6.24 kg/m2, respectively, P < 0.05; 48.05 ± 6.39 vs 45.72 ± 5.48 g/L, respectively, P < 0.05), whereas prealbumin and transferrin were not significantly different between the groups. QoL improved after food exclusion (P < 0.05).
Conclusions
An IgG-guided exclusion diet ameliorated UC symptoms and improved QoL. Interactions between IgG-based food intolerance and UC warrant further study.
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•Caffeine promoted growth and migration of paclitaxel-treated cancer cells.•Caffeine inhibited apoptosis in paclitaxel-treated cancer cells.•Caffeine down-regulated paclitaxel-induced ...α-tubulin acetylation in vitro and in vivo.•Caffeine decreased paclitaxel-induced inhibition of tumor growth.
Caffeine (1,3,7-trimethylxanthine) is a xanthine alkaloid found in a number of dietary products consumed worldwide, such as coffee, tea, and soft beverages, and is known to act as a modifying agent for cytotoxic chemotherapeutic drugs. Studies have shown that caffeine reduces the cytotoxic effects of paclitaxel and inhibits paclitaxel-induced apoptosis; however, the underlying mechanism remains unclear. Here, we investigated whether caffeine inhibits the antitumor activity of paclitaxel via down-regulation of α-tubulin acetylation. In vitro studies, involving MTT assay, wound-healing assay, cell apoptosis assay, and western blotting analysis of A549 and HeLa cells, were performed. A549 and HeLa cell-based xenografts were established, and western blotting and immunohistochemical staining were performed for in vivo studies. The results showed that caffeine promoted the growth of cancer cells treated with paclitaxel. Additionally, caffeine enhanced migration ability, inhibited apoptosis, and decreased the acetylation of α-tubulin in paclitaxel-treated cancer cells. Furthermore, caffeine decreased the inhibitory effect of paclitaxel on tumor growth through down-regulation of α-tubulin acetylation in vivo. Taken together, these findings demonstrate that caffeine inhibits the anticancer activity of paclitaxel via down-regulation of α-tubulin acetylation, suggesting that patients receiving treatment with taxanes, such as paclitaxel, should avoid consuming caffeinated beverages or foods.
Phonon focusing patterns are dependent on the existence of concave/saddle regions and acoustic axes in the slowness surface. The main feature of the focusing patterns in cubic crystals can be ...characterized by the caustic and anticaustic points in the symmetry planes. By applying the Stroh formalism, the caustic and anticaustic points in the symmetry planes are investigated in relation to degeneracies in the Stroh eigenvalue equation. A set of analytical expressions for the locations of the caustic and anticaustic points is derived for cubic crystals.
Surface acoustic wave (SAW) devices are one of the indispensable components in the radio frequency (RF) front-end of mobile phones. With the development of mobile communication technology, the ...requirements for linear specification of devices are more and more strict. Nonlinear distortions of SAW devices have a serious influence on the application of mobile RF modules. To satisfy the strict requirement of linearity of communication system, it is necessary to understand the generation mechanism of nonlinearity and study the accurate modeling, appropriate measurement methods, and nonlinear response elimination technology. In this paper, we summarize the research progress on the nonlinearity of SAW devices in recent years from four aspects: the generation mechanism, simulation methods, measurement system, and suppression technology. The nonlinear harmonics with the nonlinear Mason equivalent circuit model are simulated. Furthermore, harmonics and intermodulation signals of SAW filters are tested by the authors. Thanks to these research studies, it is of great significance to the development of future RF front-end modules with high linear SAW devices.
Slowness surface for bulk wave propagation in anisotropic media can be divided into concave, saddle and convex regions by the parabolic lines. When a parabolic line crosses a symmetry plane, it ...leaves either an inflection point or a parabolic point. Surface normal at these points is associated with cuspidal point and swallowtail point, respectively, on the wave surface and in phonon focusing patterns. By examining the degeneracies in the Stroh eigenvalue equation, we have calculated the cuspidal points in cubic crystals analytically. In this work, the parabolic point and its surface normal are discussed. The main idea is to establish a connection between the parabolic point and the extraordinary transonic state that is related to a degeneracy with a multiplicity of four in the Stroh eigenvalue equation. Such a connection yields a series of simple expressions, which determine the locations of parabolic points and the corresponding swallowtail points. The result is demonstrated using phonon focusing patterns of cubic crystals, and the method also provides a tool for general discussion of the slowness surface geometry.
Surface acoustic wave (SAW) sensors have been applied in various areas with many advantages, such as their small size, high sensitivity and wireless and passive form. Love wave mode sensors, an ...important kind of SAW sensor, are mostly used in biology and chemistry monitoring, as they can be used in a liquid environment. Common Love wave mode sensors consist of a delay line with waveguide and sensitive layers. To extend the application of Love wave mode sensors, this article reports a novel Love wave mode sensor consisting of a waveguide layer with microphononic crystals (PnCs). To analyze the properties of the new structure, the band structure was calculated, and transmission was obtained by introducing delay line structures and quasi-three-dimensional models. Furthermore, devices with a traditional structure and novel structure were fabricated. The results show that, by introducing the designed microstructure of phononic crystals in the waveguide layer, the attenuation was barely increased, and the frequency was shifted by a small amount. In the liquid environmental experiments, the novel structure with micro PnCs shows even better character than the traditional one. Moreover, the introduced microstructure can be extended to microreaction tanks for microcontrol. Therefore, this novel Love wave mode sensor is a promising application for combining acoustic sensors and microfluidics.
The existence of one-component surface waves requires a degeneracy in the Stroh sextic equation. An extraordinary zero-curvature transonic state, a point on the slowness surface where both the ...curvature and its first derivative equal zero, will yield a triple degeneracy in the Stroh equation. Relationship between extraordinary zero-curvature transonic states and one-component surface waves is investigated showing that they are linked via a space of degeneracy associated with the Stroh equation. Moreover, some generalized subsonic surface waves containing generalized Stroh eigenvectors are also found along the space of degeneracy.
► One-component supersonic surface wave is investigated in monoclinic elastic media. ► Curvature of slowness surface plays an important role to trace the surface waves. ► Other generalized surface waves are also identified along spaces of degeneracy.
Internet of Things' (IoT) applications keep emerging in all living and production scenarios. However, development tasks of support, communication, and computing are usually troublesome. An IoT ...middleware that completes such common basic tasks and assists advanced development is desired. Numerous general-purpose IoT instances have been tried in both academia and industry, while each has its own advantages and disadvantages. We abstract their characteristics into an ideal concept then build a reliable, modular, and oneM2M-compliant middleware accordingly. Our contributions include: proposing a stack of support-communication-computing to integrate excellent open-source projects; devising techniques variable and McSugar to enable flexible uniform human-thing interactions; and building implementation foundations for cutting-edge technologies such as fog computing and semantic reasoning. This middleware has been verified and applied: the case of field-cloud computing shows its efficacy in facilitating IoT research; the case of smart floriculture proves its capability in boosting IoT development. In short, with this middleware, developers and researchers can focus on top-level requirements of IoT development or experiment, instead of being trapped in the underlying technologies.
This paper presents a tri‐wideband bandpass filter (TWB‐BPF) with compact size, high band‐to‐band isolation, and multiple transmission zeros (TZs). The proposed TWB‐BPF is based on a multiple‐mode ...resonator (MMR), which is interpreted by the method of the even‐ and odd‐mode analysis technique. The MMR can excite 11 resonant modes, where the first two modes comprise the first passband, the next four modes form the second passband, and the last five modes are used to generate the third passband. In addition, 10 TZs are yielded to obtain high band‐to‐band isolation and wide stopband suppression characteristics up to 14.95fc1 (fc1 is the center frequency of the first passband). To verify the proposed filter, a TWB‐BPF with 3‐dB fractional bandwidths (FBWs) of 37.4%, 43.5%, and 40.4% is designed, fabricated, and measured.
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