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Integrating ZnS:Cu@Al2O3/polydimethylsiloxane (PDMS) flexible matrices with optical fibers is crucial for the development of practical passive sensors. However, the fluorescence coupling efficiency is constrained by the small numerical aperture of the fiber, leading to a reduction in sensor sensitivity. To mitigate this limitation, a microsphere lens was fabricated at the end of the multimode fiber, which resulted in a 21.585% enhancement in the fluorescence coupling efficiency. A passive, flexible mechanoluminescent (ML) tactile sensor (MLTS) was developed by embedding a fiber microsphere probe within a ZnS:Cu@Al2O3/PDMS film featuring a pyramid surface structure. The MLTS demonstrated exceptional pressure sensing capabilities, exhibiting rapid response times of 250 ms for loading and 200 ms for unloading, along with strong durability, surviving over 2000 cycles. It effectively distinguished Braille patterns and sandpapers of varying roughness by detecting the ML signals generated by the sensor’s surface microstructures. Notably, this sensor operates without the need for external light stimulation, making it a promising candidate for application in photonic skin and robotic tactile perception.

With the rapid advancement of microfluidic technology, the precise measurement of microflows is critical in biomedical engineering, chemical analysis, and environmental monitoring. Current measurement methods often suffer from limited scalability and potential interference with fluid dynamics. This study introduces a low detection limit (DL) flow measurement method that uses single-fiber optical tweezers to capture individual silica microspheres outside a microcapillary as flow indicators. Under fluid flow, the microspheres exhibit microscale positional shifts within the optical trap. By analyzing these signal changes in real time, accurate flow measurements are achieved. Our experimental results demonstrate significant advantages in detecting low flow rates using this method. For sample solutions with a concentration of 0.05 wt.%, the method achieves a minimum flow DL of 6 nL/min, a linearity of 0.993, a sensitivity of $- 14.36 \; \mu $ s/(nL/min), and a maximum standard deviation of approximately 0.092%. The piconewton-level optical force allows this sensor structure to detect extremely low flow rates. Additionally, the microcapillary provides a controlled and stable microflow environment, ensuring that the measurement process does not interfere with fluid flow, thereby reducing deviations.

We propose a flexible wearable respiratory sensor based on microspheres coupling, where the sensing element is a microfiber embedded in a polydimethylsiloxane (PDMS) film doped with 5- $\mu \text{m}$ -diameter silica microspheres. In this study, PDMS doped with microspheres was used to coat microfibers for the first time, and the enhancement of the evanescent field on the surface of microfibers was observed. Theoretically and experimentally, it is found that the light transmitted in the optical fiber core is effectively dragged by the microsphere, which significantly enhances the evanescent field and thus improves the sensitivity of the sensing element. During the respiratory monitoring, the pressure generated by the respiratory airflow causes the sensing element to bend, and the self-mixing interference is used to detect the power change of reflected light to reconstruct the respiratory signal. The empirical findings demonstrate a peak in sensor sensitivity at a microsphere doping concentration of 0.1 g/mL, while a subsequent augmentation in microspheres doping concentration inversely correlates with sensor sensitivity. Notably, the sensor developed with a 0.1-g/mL microspheres doping concentration exhibits an exceptional capacity for continuous, real-time differentiation among diverse respiratory signals. This innovation is characterized by its elevated sensitivity and responsiveness, evidenced by an impressively short 28-ms response time. To validate the sensor’s effectiveness, we employed the Bland–Altman statistical analysis test to assess the accuracy of respiration rate measurements using the collected data from the test subjects. The favorable outcomes we obtained offer a promising avenue for advancing research in the realm of noninvasive vital signs monitoring.

Bone-related diseases like osteoarthritis and osteoporosis impact millions globally, affecting quality of life. Osteoporosis considerably enhances the probability of bone fractures of the wrist, hip, and spine. Enhancement and acceleration of functional bone development can be achieved through the sustained delivery of growth factors (GFs) and cells in biomaterial carriers. The delivery of bioactive compounds in a targeted, spatiotemporal way that most closely resembles the natural defect repair process can be achieved by designing the carrier system with established release kinetics. Furthermore, the carrier can serve as a substrate that mimics the extracellular matrix, facilitating osteoprogenitor cell infiltration and growth for integrative tissue healing. In this report, we explore the significance of GFs within the realm of bone and cartilage tissue engineering, encompassing their encapsulation and delivery methodologies, the kinetics of release, and their amalgamation with biomaterials and stem cells (SCs) to facilitate the mending of bone fractures. Moreover, the significance of GFs in evaluating the microenvironment of bone tissue through reciprocal signaling with cells and biomaterial scaffolds is emphasized which will serve as the foundation for prospective advances in bone and cartilage tissue engineering as well as therapeutic equipment. Nanoparticles are being used in regenerative medicine to promote bone regeneration and repair by delivering osteoinductive growth factors like BMP-2, VEGF, TGF-β. These nanocarriers allow controlled release, minimizing adverse effects and ensuring growth factors are concentrated at the injury site. They are also mixed with mesenchymal stem cells (MSCs) to improve their engraftment, differentiation, and survival. This approach is a key step in developing multi-model systems that more efficiently facilitate bone regeneration. Researchers are exploring smart nanoparticles with immunomodulatory qualities to improve bonre regeneration and reduce inflammation in injury site . Despite promising preclinical results, challenges include cost management, regulatory approval, and long term safety. However, incorporating stem cell transport and growth factors in nanoparticles could revolutionize bone regeneration and offer more personalized therapies for complex bone disorders and accidents.

Background: Atherosclerosis (AS), a significant contributor to cardiovascular disease (CVD), is steadily rising with the aging of the global population. Pyroptosis and apoptosis, both caspase-mediated cell death mechanisms, play an essential role in the occurrence and progression of AS. The human pineal gland primarily produces melatonin (MT), an indoleamine hormone with powerful anti-oxidative, anti-pyroptotic, and anti-apoptotic properties. This study examined MT’s anti-oxidative stress and anti-pyroptotic effects on human THP-1 macrophages treated with nicotine. Methods: In vitro, THP-1 macrophages were induced by 1 µM nicotine to form a pyroptosis model and performed 30 mM MT for treatment. In vivo, ApoE-/-mice were administered 0.1 mg/mL nicotine solution as drinking water, and 1 mg/mL MT solution was intragastric administrated at 10 mg/kg/day. The changes in pyroptosis, apoptosis, and oxidative stress were detected. Results: MT downregulated pyroptosis, whose changes were paralleled by a reduction in reactive oxygen species (ROS) production, reversal of sirtuin3 (SIRT3), and Forkhead box O3 (FOXO3α) upregulation. MT also inhibited apoptosis, mainly caused by the interaction of caspase-1 and caspase-3 proteins. Vivo studies confirmed that nicotine could accelerate plaque formation. Moreover, mice treated with MT showed a reduction in AS lesion area. Conclusions: MT alleviates pyroptosis by regulating the SIRT3/FOXO3α/ROS axis and interacting with apoptosis. Importantly, our understanding of the inhibitory pathways for macrophage pyroptosis will allow us to identify other novel therapeutic targets that will help treat, prevent, and reduce AS-associated mortality.

Fractured anticline reservoirs are mostly developed by a line production well located at the top position and a line injecting well located at the bottom position. The production well is often interference with by multiple injecting wells, but there is little related research about multiple injecting well interferences. To solve this problem, an extended bottom-hole pressuredrop (BHPD) response model for production well interfered with by multiple injection wells was presented to capture the injection interference and gravity effect. The proposed model's correctness is validated by the software numerical simulation, and low regimes were identified by the BHPD and its derivative curve. Research results show that: (i) the BHPD derivative curve has a one-half slope line, V-shape, and one slope line in reservoir linear flow regime, inter-porosity flow regime, and interference flow regime, respectively; (ii) the drop rate of pressure increases with the increase of formation transmissibility and storability. The bigger the fracture storability, the more obvious the V-shape feature in the derivative curve of BHPD. As the inter-porosity flow coefficient increases, the V-shape feature emerges later; (iii) the beginning time of the interference flow becomes later when the interference distance increases. When the injection rate trends to the production rate, the BHPD curve shows a slight drop and its derivative curve has an intermittent rupture; (iv) the influence of the gravity effect is not ignored. Due to the gravity effect, the BHPD interfered by constant injection well like the BHPD's behavior interfered by the closed boundary. This work provides technical support for capturing the source and degree of interference from well group in the heterogeneous fractured anticline reservoir.

The majority of edge-bottom water fault-block reservoirs in China have the problem of a low recovery factor during water flooding. Most of them suffer from serious water channeling, a rapid increase in water cut, and low sweeping efficiency. Measures need to be taken to further increase the recovery factor, among which nitrogen foam flooding and viscosity reducer flooding technologies are highly anticipated for this purpose. To fill this gap, this work targets reservoirs with edge-bottom water and fault blocks. First, on the basis of evaluating the effects of foaming agent and viscosity reducer, a 2D visual large flat physical model is designed to simulate the fault-block reservoirs with edge and bottom water. Then, after comparing the oil displacement effects of nitrogen foam and viscosity reducer systems using different injection methods, the flow characteristics and action patterns of foam and viscosity reducer are studied. The recovery factor of the hybrid injection scheme increased by 18.3% compared to the water flooding and was 4.2% higher than the slug injection. The water cutoff of the hybrid injection showed a linear decrease. Finally, the experiment clarifies the impact of injection rounds on nitrogen foam with viscosity reducer flooding and summarizes the mechanism of it through the changes in the oil saturation. The viscosity reducer significantly reduces the viscosity of crude oil and assists in foam plugging. Additionally, as the injection rounds increase, the effectiveness of profile control and water plugging decreases. In addition, most methods of profile control and water plugging are one-time injection; the experiment changes it to multiple rounds and introduces a conversion method of resistivity and oil saturation innovatively. The physical displacement experiment of big-scale size two-dimensional visualization model is carried out under simulated reservoir conditions, the influence of injection methods on recovery factor is studied, and the mechanism of enhancing oil recovery is clarified. Also, it is expected to address issues in edge-bottom water reservoirs with fault blocks, such as severe water channeling and limited displacement range.

An efficient synthesis method will allow a large number of tetramic acid analogues to be synthesized for property and potency optimization. In this study, a facile and efficient method was described for the synthesis of 3-acyltetramic acids. The synthesis was accomplished mainly via (1) mild intramolecular cyclization and (2) the formation of β-ketoamides between nucleophiles and acyl Meldrum’s acids. 3-Acyltetramic acid exhibited phytotoxicity against Echinochloa crusgalliand Portulaca oleracea. At a dosage of 750 g ha–1, 6kand 6ashowed high herbicidal activity against E. crusgalli, Digitaria sanguinalisand P. oleracea, Amaranthus retroflexus, respectively. 6kinhibited the synthesis of endogenous abscisic acid, thus seedling germination and plant growth. The incorporation of various acyl Meldrum’s acids and amino acid esters was applicable to the parallel synthesis of 3-acyltetramic acids. The mode of action and herbicidal activity indicate that 3-tetramic acid had good herbicidal performance and was a promising herbicide candidate. This study will provide a reference for novel herbicide development.