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Precision operations, such as micro-injection and micro-assembly tasks, require accurate and constant torque output. Compliant constant torque mechanisms (CCTMs) can be considered as a potential alternative due to the characteristic of accurate and constant torque output without the need for complex control algorithms and structures. Therefore, it is essential to propose a general, designer-friendly, and efficient design methodology for the design of CCTMs. In this paper, we propose a methodology for designing compliant constant torque mechanisms based on a co-design process between Cartesian coordinate system and Frenet frame. We use geometrically exact beam theory to model the static deflection of the built-in flexible beams so as to analyze the overall mechanism. We transform the design of this mechanism into a typical constrained optimization problem, and solve it via highly efficient numerical methods to achieve the desired design objectives given the user-defined constraints and satisfy some specific engineering requirements. Our optimized design is thoroughly evaluated and validated through finite element method and experimental testing, demonstrating a significantly improved performance compared to existing designs. • A general methodology is proposed for designing constant torque mechanisms. • A novel model for complex-shape beams is proposed and verified by FEM. • Two desired designs are achieved via model-based optimization. • The optimized designs present better performance compared to the existing designs. • A prototype is fabricated and experimental results demonstrate its effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Ti/MoS 2 /Pt device shows enhanced endurance and superior operational uniformity. • The RS mechanism is attributed to the formation and rupture of S vacancy CFs. • Ti x S y interface layer plays an important role in reducing operating voltage. • 1T phase MoS 2 contribute to the excellent operational uniformity. Nonvolatile memories based on two-dimensional nanomaterials are of significant interest to researchers attempting to achieve robust resistive switching (RS) with simple device integration and low energy consumption. In this study, the RS behavior of a MoS 2 -based memristor was investigated using Ti and Ag as top electrodes (TEs). Compared with the memristor using the Ag TE, that employing the Ti TE not only exhibited substantially enhanced and reproducible endurance performance for up to 104 cycles, but also showed excellent operational uniformity with a coefficient of variation limited to 3.5% and 4.0% for SET and RESET voltages, respectively. Moreover, the Ti TE memristor demonstrated RS behavior after 1 month of storage under ambient conditions. The formation of a Ti x S y layer at the Ti/MoS 2 interface and the presence of an abundant 1T phase MoS 2 (or S vacancy, V S) in the initial state of the MoS 2 film contribute to its distinctive properties. This work indicates that suitable TE selection can enable the fabrication of high-performance nonvolatile MoS 2 -based memristors. [ABSTRACT FROM AUTHOR]

The electrical manipulation of magnetism is of particular importance owing to its potential applications in low-power memory devices and spintronics. In this study, we demonstrate enhanced magnetic modulation and an increased exchange bias field (HEB) in NiO films pretreated with ionic liquid (IL), which we refer to as IL-NiO films. The saturation magnetization of the IL-NiO film in the low-resistance state (LRS) is more than 2.5 times than that in the high-resistance state; this value is more than 80% higher than that of the NiO film without IL pretreatment (As-NiO). In addition, the HEB value of the IL-NiO film is more than 140% higher than that of the As-NiO film. Further analysis indicates that oxygen vacancies and metallic Ni0 are introduced into the NiO film during the IL pretreatment process, which results in the formation of thicker ferromagnetic Ni conductive filaments (CFs) after the set process. These thicker Ni CFs enhance the magnetism of the IL-NiO film and increase the coupling area between the ferromagnetic Ni and antiferromagnetic NiO in the LRS, thus leading to a larger magnetic modulation and higher HEB in the IL-NiO film. We believe that our findings can significantly contribute to further advancements in memory devices and allied applications. [ABSTRACT FROM AUTHOR]

Compliant deployable mechanisms (CDMs), as a novel and promising type of mechanisms, have been gradually used in medical industry, aerospace and other engineering fields that require high space utilization and compactness. Therefore, it is necessary to develop a general and efficient methodology to design and analyze CDMs. This paper proposes a general framework for designing and analyzing CDMs. The proposed framework has been verified by finite element method (FEM) first. Then, for practical validation, we design two types of compliant deployable mechanisms for different application scenarios within this framework, and experimental testing has been conducted to prove the feasibility of the proposed framework. Compared to the existing methods for designing CDMs, this framework demonstrates a more general scheme where different engineering scenarios can be taken into account to meet the design requirements, presenting several desired advantages over the existing methods, such as higher accuracy and less computational expense. • We propose a general framework for designing compliant deployable mechanisms (CDMs). • The framework also has the advantages of high accuracy and low calculation costs. • We present two types of CDMs to provide feasible schemes for future applications. [ABSTRACT FROM AUTHOR]

The development of wearable detection devices that can achieve noninvasive, on-site and real-time monitoring of sweat metabolites is of great demand and practical significance for point-of-care testing and healthcare monitoring. Monitoring uric acid (UA) content in sweat provides a simple and promising way to reduce the risk of gout and hyperuricemia. Traditional bioenzyme based UA assays suffer from high cost, poor stability, inconvenience for storage and easy deactivation of bioenzymes. Wearable microfluidic colorimetric detection device for sweat UA detection has not been reported. The development of novel wearable microfluidic colorimetric detection chip with no requirement of bioenzymes for sweat UA detection is of great importance for health care monitoring. Firstly, Co@MnO 2 nanozyme with high oxidase-like activity was synthesized and characterized. Co@MnO 2 can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) directly to generate blue-green colored ox-TMB. Green colored 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) radical (ABTS·+) was produced by the oxidation of ABTS by potassium persulfate. UA exhibits distinct quenching effect on Co@MnO 2 catalyzed TMB colorimetric reaction system and ABTS·+ based colorimetric system, leading to obvious color fading of the two colorimetric systems. Then, a flexible microfluidic colorimetric detection chip for UA detection was fabricated by assembling Co@MnO 2 /TMB modified paper chips and ABTS·+ modified paper chips into a polydimethylsiloxane (PDMS) microfluidic chip. The fabricated microfluidic colorimetric detection chip exhibits good linear relationship for sweat UA detection. The linear range is from 20 to 200 μmol/L with detection limit as low as 6.6 μmol/L. Good results were obtained for the detection of UA in actual sweat from three volunteers. This work provides two bio-enzyme free colorimetric detection systems for UA detection. Furthermore, a simple, low-cost and selective flexible wearable microfluidic colorimetric detection chip was fabricated for noninvasive and on-site detection of sweat UA, which holds great application potential for personal health monitoring and point-of-care testing. [Display omitted] • Co@MnO 2 nanozyme with good oxidase-like activity was synthesized. • Two bio-enzyme free colorimetric detection methods for UA detection were developed. • A flexible wearable microfluidic colorimetric detection chip for sweat UA detection was fabricated. • Co@MnO 2 catalyzed TMB colorimetric reaction system and ABTS·+ based colorimetric system were combined together. • Satisfied results were obtained for actual sweat UA detection. [ABSTRACT FROM AUTHOR]

Summary: To expand the cultivation area of apple (Malus×domestica Borkh.) and select resistant varieties by genetic engineering, it is necessary to clarify the mechanism of salt and osmotic stress tolerance in apple. The MdMYB46 transcription factor was identified, and the stress treatment test of MdMYB46‐overexpressing and MdMYB46‐RNAi apple lines indicated that MdMYB46 could enhance the salt and osmotic stress tolerance in apple. In transgenic Arabidopsis and apple, MdMYB46 promoted the biosynthesis of secondary cell wall and deposition of lignin by directly binding to the promoter of lignin biosynthesis‐related genes. To explore whether MdMYB46 could coordinate stress signal transduction pathways to cooperate with the formation of secondary walls to enhance the stress tolerance of plants, MdABRE1A, MdDREB2A and dehydration‐responsive genes MdRD22 and MdRD29A were screened out for their positive correlation with osmotic stress, salt stress and the transcriptional level of MdMYB46. The further verification test demonstrated that MdMYB46 could activate their transcription by directly binding to the promoters of these genes. The above results indicate that MdMYB46 could enhance the salt and osmotic stress tolerance in apple not only by activating secondary cell wall biosynthesis pathways, but also by directly activating stress‐responsive signals. [ABSTRACT FROM AUTHOR]

Fluorescent lateral flow immunoassay (LFA) is one of the most common analytical platforms for point-of-care testing (POCT), which is capable of facile and early screening of biomarkers. Notably, fluorescent probes play a decisive role in analytical performances of LFA. Herein, we report a novel LFA based on the rare earth doped nanoparticles (RENPs) emitting in the second near-infrared (NIR-II) window for the detection of biomarkers, such as carcinoembryonic antigen (CEA). Benefiting from the dual fluorescent emission at NIR-II window, strong fluorescent penetration, low autofluorescence and excellent photostability of RENPs, this proposed NIR-II LFA displays a good linear relationship ranging from 1 to 320 ng mL−1. The detection limit is as low as 0.37 ng mL−1, which is of 13.5 times lower than the clinical cutoff value. Overall, NIR-II LFA biosensing platform based RENPs not only exhibits high sensitivity, accuracy and specificity, but also have characteristics of rapidity, simplicity and low cost. It holds high potential for early diagnosis of tumor biomarkers in POCT. [ABSTRACT FROM AUTHOR]

Apple trees encounter problems such as stressful environments and pathogen infection throughout their entire growth and development, which limits apple production. WRKY transcription factors play a vital role in the defense against pathogens, but their functions in apple trees need to be further explored. In this study, the MdWRKY61 gene, which encodes the WRKY61 protein of the WRKY group II family, was isolated from GL-3 apple. Tobacco subcellular localization experiments showed that the MdWRKY61 protein is located in the nucleus. Quantitative reverse transcription PCR analysis suggested that MdWRKY61 is highly expressed in the roots and fruits of apples and is rapidly induced in response to salicylic acid, jasmonic acid and Colletotrichum siamense. We obtained MdWRKY61 overexpression lines through Agrobacterium -mediated stable genetic transformation of apple. Subsequent experiments revealed that overexpression of MdWRKY61 increased the resistance of apple to Colletotrichum siamense and promoted the upregulation of defense-related gene expression. Taken together, our data provide insights that MdWRKY61 plays an important role in apple resistance to fungal disease. • First research on the function of MdWRKY61. • MdWRKY61 was induced by Colletotrichum siamense , SA and JA. • MdWRKY61 can improve the resistance of apples to Colletotrichum siamense. [ABSTRACT FROM AUTHOR]

• First report on ACLSV-derived vsiRNA. • An ACLSV-derived vsiR1360(-) targets host hawthorn CpLRR-RLK1 gene. • CpLRR-RLK1 is a novel receptor protein of the LRRII-RLK subfamily. • CpLRR-RLK1 can enhance the resistance of Arabidopsis to bacteria disease Pst DC3000. Virus-derived small interfering RNAs (vsiRNAs) can target not only viruses but also plant genes. Apple chlorotic leaf spot virus (ACLSV) is an RNA virus that infects Rosaceae plants extensively, including apple, pear and hawthorn. Here, we report an ACLSV-derived vsiRNA [vsiR1360(-)] that targets and down-regulates the leucine-rich repeat receptor-like kinase 1 (LRR-RLK1) gene of hawthorn (Crataegus pinnatifida). The targeting and cleavage of the CpLRR-RLK1 gene by vsiR1360(-) were validated by RNA ligase-mediated 5' rapid amplification of cDNA ends and tobacco transient transformation assays. And the CpLRR-RLK1 protein fused to green fluorescent protein localized to the cell membrane. Conserved domain and phylogenetic tree analyses showed that CpLRR-RLK1 is closely related to the proteins of the LRRII-RLK subfamily. The biological function of CpLRR-RLK1 was explored by heterologous overexpression of CpLRR-RLK1 gene in Arabidopsis. The results of inoculation of Pst DC3000 in Arabidopsis leaves showed that the symptoms of CpLRR-RLK1 overexpression plants infected with Pst DC3000 were significantly reduced compared with the wild type. In addition, the detection of reactive oxygen species and callose deposition and the expression analysis of defense-related genes showed that the CpLRR-RLK1 gene can indeed enhance the resistance of Arabidopsis to bacteria disease. [ABSTRACT FROM AUTHOR]