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Flexible pressure sensors are lightweight and highly sensitive, making them suitable for use in small portable devices to achieve precise measurements of tiny forces. This article introduces a low-cost and easy-fabrication strategy for piezoresistive flexible pressure sensors. By embedding silver nanowires into a polydimethylsiloxane layer with micro-pyramids on its surface, a flexible pressure sensor is created that can detect low pressure (17.3 Pa) with fast response (<20 ms) and high sensitivity (69.6 mA kPa−1). Furthermore, the pressure sensor exhibits a sensitive and stable response to a small amount of water flowing on its surface. On this basis, the flexible pressure sensor is innovatively combined with a micro-rotor to fabricate a novel urinary flow-rate meter (uroflowmeter), and results from a simulated human urination experiment show that the uroflowmeter accurately captured all the essential shape characteristics that were present in the pump-simulated urination curves. Looking ahead, this research provides a new reference for using flexible pressure sensors in urinary flow-rate monitoring. ARTICLE HIGHLIGHTS: • A flexible pressure sensor is presented based on a micro-pyramid array and silver nanowires and with low detection limit, high sensitivity, and fast response. • The sensor responds accurately and stably to human pulse signals and rapidly changing cyclic loads. • The sensor can accurately and sensitively detect dynamic water flow passing over its upper surface, and the uroflowmeter designed using it has considerably high detection accuracy. [ABSTRACT FROM AUTHOR]

Gastrointestinal cancers have become an important cause of cancer-related death in humans. Improving the early diagnosis rate of gastrointestinal tumors and improving the effect of surgical treatment can significantly improve the survival rate of patients. The conventional diagnostic method is high-definition white-light endoscopy, which often leads to missed diagnosis. For surgical treatment, intraoperative tumor localization and post-operative anastomotic state evaluation play important roles in the effect of surgical treatment. As a new imaging method, near-infrared fluorescence imaging (NIRFI) has its unique advantages in the diagnosis and auxiliary surgical treatment of gastrointestinal tumors due to its high sensitivity and the ability to image deep tissues. In this review, we focus on the latest advances of NIRFI technology applied in early diagnosis of gastrointestinal tumors, identification of tumor margins, identification of lymph nodes, and assessment of anastomotic leakage. In addition, we summarize the advances of NIRFI systems such as macro imaging and micro imaging systems, and also clearly describe the application process of NIRFI from system to clinical application, and look into the prospect of NIRFI applied in the theranostics of gastrointestinal tumors. [ABSTRACT FROM AUTHOR]

Abstract: The design and synthesis of multifunctional systems with high biocompatibility are very significant for the future of clinical applications. Herein, we report a microwave-assisted rapid synthesis of multifunctional Eu3+/Gd3+ dual-doped hydroxyapatite (HAp) nanorods, and the photoluminescence (PL), drug delivery and in vivo imaging of as-prepared Eu3+/Gd3+ doped HAp nanorods. The photoluminescent and magnetic multifunctions of HAp nanorods are realized by the dual-doping with Eu3+ and Gd3+. The PL intensity of doped HAp nanorods can be adjusted by varying Eu3+ and Gd3+ concentrations. The magnetization of doped HAp nanorods increases with the concentration of doped Gd3+. The as-prepared Eu3+/Gd3+-doped HAp nanorods exhibit inappreciable toxicity to the cells in vitro. More importantly, the Eu3+/Gd3+-doped HAp nanorods show a high drug adsorption capacity and sustained drug release using ibuprofen as a model drug, and the drug release is governed by a diffusion process. Furthermore, the noninvasive visualization of nude mice with subcutaneous injection indicates that the Eu3+/Gd3+-doped HAp nanorods with the photoluminescent function are suitable for in vivo imaging. In vitro and in vivo imaging tests indicate that Eu3+/Gd3+-doped HAp nanorods have a potential in applications such as a multiple-model imaging agent for magnetic resonance (MR) imaging, photoluminescence imaging and computed tomography (CT) imaging. The Eu3+/Gd3+ dual-doped HAp nanorods are promising for applications in the biomedical fields such as multifunctional drug delivery systems with imaging guidance. [Copyright &y& Elsevier]

A selective CO evolution from photoreduction of CO 2 in water was achieved on a noble-metal-free, carbide-based composite catalyst, as demonstrated by a CO selectivity of 98.3% among all carbon-containing products and a CO evolution rate of 29.2 μmol h -1 , showing superiority to noble-metal-based catalyst. A rapid separation of the photogenerated electron-hole pairs and improved CO 2 adsorption on the surface of the carbide component are responsible for the excellent performance of the catalyst. The high CO selectivity is accompanied by a predominant H 2 evolution, which is believed to provide a proton-deficient environment around the catalyst to favor the formation of hydrogen-deficient carbon products. The present work provides general insights into the design of a catalyst with a high product selectivity and also the carbon evolution chemistry during a photocatalytic reaction.

Objective: Human induced pluripotent stem (iPS) cells exhibit great potential for generating functional human cells for medical therapies. In this paper, we report for use of human iPS cells labeled with fluorescent magnetic nanoparticles (FMNPs) for targeted imaging and synergistic therapy of gastric cancer cells in vivo., Methods: Human iPS cells were prepared and cultured for 72 h. The culture medium was collected, and then was co-incubated with MGC803 cells. Cell viability was analyzed by the MTT method. FMNP-labeled human iPS cells were prepared and injected into gastric cancer-bearing nude mice. The mouse model was observed using a small-animal imaging system. The nude mice were irradiated under an external alternating magnetic field and evaluated using an infrared thermal mapping instrument. Tumor sizes were measured weekly., Results: iPS cells and the collected culture medium inhibited the growth of MGC803 cells. FMNP-labeled human iPS cells targeted and imaged gastric cancer cells in vivo, as well as inhibited cancer growth in vivo through the external magnetic field., Conclusion: FMNP-labeled human iPS cells exhibit considerable potential in applications such as targeted dual-mode imaging and synergistic therapy for early gastric cancer.