Long‐term implantation of biomedical electronics into the human body enables advanced diagnostic and therapeutic functionalities. However, most long‐term resident electronics devices require invasive procedures for implantation as well as a specialized receiver for communication. Here, a gastric resident electronic (GRE) system that leverages the anatomical space offered by the gastric environment to enable residence of an orally delivered platform of such devices within the human body is presented. The GRE is capable of directly interfacing with portable consumer personal electronics through Bluetooth, a widely adopted wireless protocol. In contrast to the passive day‐long gastric residence achieved with prior ingestible electronics, advancement in multimaterial prototyping enables the GRE to reside in the hostile gastric environment for a maximum of 36 d and maintain ≈15 d of wireless electronics communications as evidenced by the studies in a porcine model. Indeed, the synergistic integration of reconfigurable gastric‐residence structure, drug release modules, and wireless electronics could ultimately enable the next‐generation remote diagnostic and automated therapeutic strategies.

Most current image super-resolution (SR) methods based on deep convolutional neural networks (CNNs) use residual learning in network structural design, which contributes to effective back propagation, thus improving SR performance by increasing model scale. However, deep residual network suffers some redundancy in model representational capacity by introducing short paths, thus hindering the full mining of model capacity. In addition, blindly enlarging the model scale will cause more problems in model training, even with residual learning. In this work, a novel network architecture is introduced to fully exploit the representational capacity of the model, where all skip connections are implemented by weighted channel concatenation, followed by a 1 × 1 conv layer. Based on this weighted skip connection, we construct the building modules of our model, and improve the global feature fusion (GFF). Unlike most previous models, all skip connections in our network are channel-concatenated and no residual connection is adopted. It is therefore termed as fully channel-concatenated network (FC 2 N). Due to the full exploitation of model capacity, the proposed FC 2 N achieves better performance than other advanced models with fewer model parameters. Extensive experiments demonstrate the superiority of our method to other methods, in terms of both quantitative metrics and visual quality.

Both the existence of CeO2 surface oxygen vacancies and their dynamic change during reaction may cause crucial influence on the soot oxidation behavior of Ag/CeO2.

Through the efforts of many research groups and consortia over the last several years, the acousto-optic tunable filter has evolved into a device capable of high-performance wavelength-selective optical switching and wavelength routing in dense WDM systems, The distinguishing feature of the AO switch is its ability to sustain many independent coexisting passbands, thus allowing in a simple integrated-optic device, the parallel processing capability of much more complex designs, The AOTF has also found a role in active gain equalization of optically amplified networks, In this paper, we review the design of both hybrid and fully integrated AO switches. The theory of operation is reviewed and recent advances in passband engineering are described which have made low-crosstalk, wavelength misalignment-tolerant switches to be possible, Advanced issues such as mechanisms of interchannel crosstalk and its reduction are also discussed, Both device and system issues are covered

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MR contrast agents are used to improve the detectability of pathologic conditions. In this study we clarify the mechanism of action of a newly developed superparamagnetic agent (AMI-25, Advanced Magnetics Inc., Cambridge, MA). Transverse relaxation rates were measured from segments of rat brain, heart, and liver using a CPMG pulse sequence. Relaxation rates varied with the time interval between the refocusing pulses in the sequence (tau). The diffusion effect on signal intensity was quantitated from the variation of T2 with tau. We find that diffusion in the presence of microscopic field gradients reduces T2, and that this effect differs in magnitude among tissues. Superparamagnetic iron oxide particles enhance this T2 reduction. The dependence of T2 upon tau suggests a model of restricted diffusion. Tissue image contrast induced by superparamagnetic iron oxide in spin-echo NMR studies is the result of a combination of diffusion-dependent and diffusion-independent differences in transverse relaxation.

A curvature sensor based on a polarization-dependent in-fiber Mach-Zehnder interferometer (MZI) is proposed. The MZI is fabricated by core-offset fusion splicing one section of polarization maintaining fiber (PMF) between two single mode fibers (SMFs). Two independent interference patterns corresponding to the two orthogonal polarization modes for the PMF are obtained. The couple efficiency between the core mode and the cladding mode decreased with the increasing of the bending on the MZI part. The curvature variation on the MZI part can be obtained by detecting the fringe visibility of the interference patterns. A difference arithmetic demodulation method is used to reduce the effects of the light source power fluctuations and temperature cross-sensitivity. Experimental results show that maximal sensitivity of -0.882 dB/m(-1) is obtained under a measurement range of 0.1 to 0.35 m(-1) for the curvature sensor. With the use of difference arithmetic demodulation method, the temperature-curvature cross-sensitivity and light source power fluctuations effects on the proposed sensor are decreased by 94% and 91%, respectively.

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