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Liquid manipulation using tubular actuators finds diverse applications ranging from microfluidics, printing, liquid transfer to micro‐reactors. Achieving flexible and simple regulation of manipulated liquid droplets during transport is crucial for the tubular liquid actuators to perform complex and multiple functions, yet it remains challenging. Here, a facile tubular actuator for directional transport of various liquid droplets under the control of an externally applied magnetic field is presented. The surfaces of the actuator can be engineered with submillimeter‐sized through‐hole pores, which enables the liquid droplet to be easily modulated in the transport process. Furthermore, the liquid actuator with featured through‐hole pores is expanded to function as a switch in an integrated external electric circuit by magnetically controlling the motion of a conductive liquid droplet. This work develops a strategy for regulating liquid droplets in the tubular actuation systems, which may inspire ideas for designing functional liquid actuators with potential applications in microfluidics, microchemical reaction, liquid switch, and liquid robotics. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced thermoplastic (CFRTP) composites, known for their excellent mechanical properties and environmental sustainability, are highly sought‐after in aerospace, energy, and many other fields. Grinding could be used to realize the high‐accuracy and low‐damage machining of CFRTP components. However, due to the temperature sensitivity and water absorption of CFRTP, dry and flood lubrication grinding could cause thermal damage and hygrothermal aging, respectively. In addition, these methods could lead to dust and excessive cutting fluids harmful to the environment. Addressing these bottlenecks, this study is the first to propose using oil‐on‐water minimum quantity lubrication (OoW‐MQL) to grind CFRTP. Experiments including various lubricating conditions and grinding parameters were performed to investigate the grinding performance. Experimental results showed that OoW‐MQL with the oil–water proportion of 1:1 outperformed the other lubricating conditions, achieving the best surface quality with the lowest grinding forces and temperatures. The optimal oil–water proportion remained almost unchanged under different grinding parameters. Furthermore, importance analysis using the extreme gradient boosting (XGBoost) algorithm demonstrated that oil–water proportion was the most critical factor affecting surface roughness. This study proves the feasibility of OoW‐MQL and provides technical guidance for high‐quality grinding of CFRTP. Highlights: Oil‐on‐water minimum quantity lubrication (OoW‐MQL) was proposed to grind carbon fiber reinforced thermoplastic (CFRTP) composites.The experimental results of grinding forces, grinding temperatures, surface roughness and surface morphologies were analyzed, which proved that OoW‐MQL with oil–water proportion (1,1) had outstanding lubricating and cooling capability.The effect of grinding parameters on the optimal oil–water proportion was proved to be negligible through comparative tests under grinding parameters of high force and high temperature.Quantitative analysis using the extreme gradient boosting (XGBoost) algorithm identified the oil–water proportion as the most critical factor influencing surface roughness. [ABSTRACT FROM AUTHOR]

While state‐of‐the‐art organic photovoltaics (OPVs) have been achieved by halogen modification strategies for active layer materials, the stability of these OPVs can be compromised by the presence of halogen ions at the interface and within the photoactive layer. Herein, halogen‐free photoactive layer‐based OPV cells are fabricated and systematically studied to understand and explore the working principle and potential of this class of OPV devices. For the first time, a champion efficiency of 13.12% is achieved for the inverted device (ITO/AZO/AL/MoO3/Ag) based on the nonhalogenated photoactive layer PBDB‐T:BTP‐M. Superior metal electrode stability is confirmed for the unencapsulated PBDB‐T:BTP‐M devices aged at 85 °C in the air atmosphere compared to the halogenated PM6:Y6 devices. Specifically, better thermal stability is verified for the nonhalogenated device without 1‐chloronaphthalene (1‐CN) additive compared to the device with 1‐CN additive, with 89% of the initial efficiency retained after being aged for 900 h at 85 °C in the N2 atmosphere. These results evidence the halogen/halide impacts on device stability and demonstrate the potential for nonhalogenated OPVs to achieve efficient and stable performance, benefiting the development and practical application of this technology. [ABSTRACT FROM AUTHOR]

Grinding could be used to enhance accuracy and quality of carbon fiber‐reinforced poly‐ether‐ether‐ketone (CF/PEEK) composites. However, the grinding mode, namely up‐grinding (UG) or down‐grinding (DG), is usually neglected while unbefitting grinding mode choice may cause inferior surface quality. To investigate effects of grinding modes on grinding performance of anisotropic CF/PEEK, grinding experiments in UG and DG were carried out under different fiber orientation angles θ. Experimental results indicated that maximum grinding temperatures and normal grinding forces in UG were lower than DG regardless of the abrasive grit sizes. Material removal mechanisms of CF/PEEK affected by grinding mode were revealed by analyzing morphologies of surface, chip and grinding wheel. When θ = 0°, the dominant mechanisms in DG were extrusion fracture and fiber deformation, while they were interface shear debonding and bending fracture in UG. When θ = 90°, the dominant mechanisms in DG included interface layer separation and bending fracture, while they were shear and extrusion fracture of well‐supported fibers in UG. Thus, UG was more favorable for material removal, obtaining lower surface roughness values, fewer machining defects and less wheel wear than DG. This study will provide technical guidance for high‐quality grinding of carbon fiber‐reinforced thermoplastic composites. Highlights: The effects of grinding modes (DG and UG) on the grinding performance of anisotropic CF/PEEK composites were investigated.Material removal mechanisms of CF/PEEK affected by grinding mode were revealed under different fiber orientation angles.The maximum grinding temperatures and normal grinding forces in UG were lower than DG.UG was more favorable for material removal in grinding, and could produce better ground surface quality than DG. [ABSTRACT FROM AUTHOR]

Background: Physical fitness in the preschool years is considered a marker of current and future health. Therefore, understanding physical fitness levels of preschool children is necessary. Furthermore, the use of field-based methods to measure physical fitness is essential for assessing children in authentic venues such as schools. Hence, the main purpose of this study was to describe the physical fitness of Chinese preschool children across field-based methods considering a statement of confidence intervals for reference in physical fitness in each age and genders. Methods: A total of 619 children (296 boys and 323 girls) aged 3–6 years old from China participated in the present study. Physical fitness was measured using the Chinese National Physical Fitness Measurement (CNPFM-Pre) battery, which included the tennis ball throw (upper-limb muscular strength), standing long jump (lower-limb muscular strength), shuttle run test (speed-agility), double-leg timed hop (coordination), sit-and-reach (flexibility), and balance beam test (dynamic balance). Results: The results revealed significant differences in gender for standing long jump (SLJ; η2 = 0.012, p = 0.007), tennis ball throw (TT; η2 = 0.081, p < 0.001), sit-and-reach (SR; η2 = 0.114, p < 0.001), and one-legged stance test (OST; η2 = 0.037, p < 0.001). Age had positive effects on all physical fitness performance tests, as the shuttle run test (η2 = 0.672, p < 0.001), SLJ (η2 = 0.513, p < 0.001), TT (η2 = 0.394, p < 0.001), double-legged timed hop test (DTH; η2 = 0.445, p < 0.001), SR (η2 = 0.069, p < 0.001), balance beam test (BBT; η2 = 0.367, p < 0.001), and OST (η2 = 0.336, p < 0.001). Older preschool children performed better than their younger counterparts in all the tests. No significant interactions between age groups and gender were found. Conclusions: This study provided age- and gender-specific physical fitness performance data in Chinese preschool children. Gender differences in physical fitness tests performance already exists at the preschool age. All physical fitness component results increased with age in this cohort. These findings can help healthcare, physical education, and pediatric professionals understand the physical fitness development of preschool children at different ages and help design sports tasks for preschool boys and girls. [ABSTRACT FROM AUTHOR]

Background: Cervical squamous cell carcinoma (CSCC) is a prevalent gynecological malignancy worldwide. Current treatments for CSCC can impact fertility and cause long-term complications, underscoring the need for new therapeutic strategies. Oncolytic virotherapy has emerged as a promising option for cancer treatment. Previous research has demonstrated the oncolytic activity of the coxsackievirus B3 strain 2035 A (CVB3/2035A) against various tumor types. This study aims to evaluate the clinical viability of CVB3/2035A for CSCC treatment, focusing on its oncolytic effect in patient-derived CSCC organoids. Methods: The oncolytic effects of CVB3/2035A were investigated using human CSCC cell lines in vitro and mouse xenograft models in vivo. Preliminary tests for tumor-selectivity were conducted on patient-derived CSCC tissue samples and compared to normal cervical tissues ex vivo. Three patient-derived CSCC organoid lines were developed and treated with CVB3/2035A alone and in combination with paclitaxel. Both cytotoxicity and virus replication were evaluated in vitro. Results: CVB3/2035A exhibited significant cytotoxic effects in human CSCC cell lines and xenograft mouse models. The virus selectively induced oncolysis in patient-derived CSCC tissue samples while sparing normal cervical tissues ex vivo. In patient-derived CSCC organoids, which retained the immunohistological characteristics of the original tumors, CVB3/2035A also demonstrated significant cytotoxic effects and efficient replication, as evidenced by increased viral titers and presence of viral nucleic acids and proteins. Notably, the combination of CVB3/2035A and paclitaxel resulted in enhanced cytotoxicity and viral replication. Conclusions: CVB3/2035A showed oncolytic activity in CSCC cell lines, xenografts, and patient-derived tissue cultures and organoids. Furthermore, the virus exhibited synergistic anti-tumor effects with paclitaxel against CSCC. These results suggest CVB3/2035A could serve as an alternative or adjunct to current CSCC chemotherapy regimens. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvesters (PEHs) have drawn considerable attention due to their unique ability to convert ambient mechanical energy to electrical energy. These devices are widely implemented in numerous applications such as wearable technology, structural health monitoring, and renewable energy systems. In this work, a novel approach that seamlessly integrates arbitrary metastructures into the substrate layer of cantilever beam‐based PEHs is presented. The corresponding performance of each PEH design is evaluated via an experimentally validated finite element model. This is the first systematic study to explore 3D metastructures with various unit cell configurations, unit cell numbers, and porosity levels. Compared with the existing PEH designs, implementation of a 3D auxetic metastructure with 85% porosity single unit cell design can demonstrate a substantial enhancement in output power, reaching 48.16 mW, and a high normalized power density (NPD) of 2.1131 µW mm−3 g−2 Hz−1. Results show that there are competing requirements for improving the performance of PEHs. On one hand, low metastructure stiffness is preferred to achieve high power output at low resonant frequency. On the other hand, metastructures designs with low stiffness may induce excessive distortion in the substrate layer, leading to mechanical energy loss. This deformation mechanism adversely affects the mechanical to electrical energy conversion efficiency. Detailed guidelines for designing and manufacturing high‐performance PEHs are discussed in this work. [ABSTRACT FROM AUTHOR]