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Abstract CRISPR-Cas12a system, characterized by its precise sequence recognition and cleavage activity, has emerged as a powerful and programmable tool for molecular diagnostics. However, current CRISPR-Cas12a-based nucleic acid detection methods, particularly microRNA (miRNA) detection, necessitate additional bio-engineering strategies to exert control over Cas12a activity. Herein, we propose an engineered target-responsive hairpin DNA activator (TRHDA) to mediate forward tearing protospacer activated CRISPR-Cas12a system, which enables direct miRNA detection with high specificity and sensitivity. Target miRNA specifically binding to hairpin DNA can drive forward tearing protospacer in the stem sequence of hairpin structure, facilitating the complementarity between crRNA spacer and protospacer to activate Cas12a. Upon the hairpin DNA as input-responsive activator of Cas12a, a universal biosensing method enables the multiple miRNAs (miR-21, let-7a, miR-30a) detection and also has exceptional capability in identifying single-base mismatches and distinguishing homologous let-7/miR-30 family members. Besides, TRHDA-mediated Cas12a-powered biosensing has realized the evaluation of miR-21 expression levels in diverse cellular contexts by intracellular imaging. Considering the easy programmability of hairpin DNA in responsive region, this strategy could expand for the other target molecules detection (e.g., proteins, micromolecules, peptides, exosomes), which offers significant implications for biomarkers diagnostics utilizing the CRISPR-Cas12a system toolbox. Graphical abstract

Abstract Tungsten trioxide (WO3) has been recognized as the most promising photocatalyst for highly selective oxidation of methane (CH4) to formaldehyde (HCHO), but the origin of catalytic activity and the reaction manner remain controversial. Here, we take {001} and {110} facets dominated WO3 as the model photocatalysts. Distinctly, {001} facet can readily achieve 100% selectivity of HCHO via the active site mechanism whereas {110} facet hardly guarantees a high selectivity of HCHO along with many intermediate products via the radical way. In situ diffuse reflectance infrared Fourier transform spectroscopy, electron paramagnetic resonance and theoretical calculations confirm that the competitive chemical adsorption between CH4 and H2O and the different CH4 activation routes on WO3 surface are responsible for diverse CH4 oxidation pathways. The microscopic mechanism elucidation provides the guidance for designing high performance photocatalysts for selective CH4 oxidation.

With multi-layers and multi-indexes, dam health diagnosis is an important way to diagnose the structural safety and health operation of dams. This study focuses on the measurement of diagnosis indexes in dam health diagnosis. The existing methods of constructing diagnosis indexes are mainly based on the subjective judgment of expert knowledge, and lack of consideration of the internal mapping relationship between diagnosis indexes and dam health levels. Therefore, it is necessary to introduce new theories and new methods to study the objective measurement of diagnostic indexes in combination with the characteristics of dam health diagnosis. Based on the Dempster–Shafer (D–S) evidence theory, a new concept lattices-based model for building basic probability assignments (BPAs) is proposed in this study. First, concept lattices under hesitant fuzzy linguistic term sets (HFLTSs) were established to formalize the qualitative and quantitative expression of expert knowledge. Then we defined a new distance of HFLTSs, named NWD. NWD is strict in mathematical definition and considers the non-overlapping HFLTSs. Based on NWD, the weight of the monitoring point for each health level was obtained through similarity analysis and finally transformed into the corresponding BPA. An engineering project demonstrated that the BPAs developed in this study could adequately describe the attributes of diagnosis indexes, forming reliable bases for the comprehensive diagnosis fusion. Simultaneously, the proposed method of building the BPA can significantly improve assignment efficiency, which can shed light on the development of dam operation behavior modelling.

Abstract In this work, Ti3C2Tx MXene was identified as efficient nanozyme with area-dependent electrocatalytic activity in oxidation of phenolic compounds, which originated from the strong adsorption effect between the phenolic hydroxyl group and the oxygen atom on the surface of Ti3C2Tx MXene flake. On the basis of the novel electrocatalytic activity, Ti3C2Tx MXene was combined with alkaline phosphatase to construct a novel cascading catalytic amplification strategy using 1-naphthyl phosphate (1-NPP) as substrate, thereby realizing efficient electrochemical signal amplification. Taking advantage of the novel cascading catalytic amplification strategy, an electrochemical biosensor was fabricated for BCR/ABL fusion gene detection, which achieved excellent sensitivity with linear range from 0.2 fM to 20 nM and limit of detection down to 0.05 fM. This biosensor provided a promising tool for ultrasensitive fusion gene detection in early diagnosis of chronic myelogenous leukemia and acute lymphocytic leukemia. Moreover, the manageable catalytic activity of MXene broke a path for developing nanozymes, which possessed enormous application potential in not only electrochemical analysis but also the extensive fields including organic synthesis, pollutant disposal and so on. Graphical Abstract

Vibration exercise (VE) has shown promising results for improving muscle strength and power performance when superimposed on high-level muscle contraction. However, low-level contraction may be more preferable in many rehabilitation programs due to the weakness of the patients. Unfortunately, the effects and underlying physiological mechanisms of VE superimposed on low-level contraction are unclear. This study aims to investigate the fatiguing effects and motor unit (MU) firing patterns during VE with low-level muscle contraction. Twenty-one healthy participants performed 60-s isometric contraction of the upper limb under a baseline force at ${30}\%$ maximum voluntary contraction and superimposed vibration with an amplitude of ${50}\%$ baseline and different frequencies at 0 Hz (control), 15, 25, 35, and 45 Hz. High-density surface electromyography (EMG) was recorded on the biceps brachii. The decay in muscle fiber conduction velocity, calculated in 3-s sliding windows, was employed as an indicator of myoelectric fatigue. MU firing patterns were obtained by decomposing the high-density EMG into MU spike trains. VE, particularly at 25 Hz, produces increased myoelectric fatigue as compared to the control condition. Besides, synchronized MU discharges are observed at the vibration frequency for 15- and 25-Hz VE and the sub-harmonics for 35- and 45-Hz VE. Furthermore, VE-induced increase in MU synchronization (as compared to control) seems to decrease with myoelectric fatigue. Significance: Our findings suggest that VE may be a suitable modality for rehabilitation programs, providing useful insights for subscribing appropriate VE training protocols.

IntroductionBeneficial effects have been observed for mechanical vibration stimulation (MVS), which are mainly attributed to tonic vibration reflex (TVR). TVR is reported to elicit synchronized motor unit activation during locally applied vibration. Similar effects are also observed in a novel vibration system referred to as functional force stimulation (FFS). However, the manifestation of TVR in FFS is doubted due to the use of global electromyography (EMG) features in previous analysis. Our study aims to investigate the effects of FFS on motor unit discharge patterns of the human biceps brachii by analyzing the motor unit spike trains decoded from the high-density surface EMG.MethodsEighteen healthy subjects volunteered in FFS training with different amplitudes and frequencies. One hundred and twenty-eight channel surface EMG was recorded from the biceps brachii and then decoded after motion-artifact removal. The discharge timings were extracted and the coherence between different motor unit spike trains was calculated to quantify synchronized activation.Results and discussionSignificant synchronization within the vibration cycle and/or its integer multiples is observed for all FFS trials, which increases with increased FFS amplitude. Our results reveal the basic physiological mechanism involved in FFS, providing a theoretical foundation for analyzing and introducing FFS into clinical rehabilitation programs.

Abstract Background Cyclin-dependent kinase 16 (CDK16) is an atypical PCTAIRE kinase, and its activity is dependent on the Cyclin Y (CCNY) family. Ccnys have been reported to regulate mammary stem cell activity and mammary gland development, and CCNY has been recognized as an oncoprotein in various cancers, including breast cancer. However, it remains unclear whether CDK16 has a role in breast cancer and whether it can be used as a therapeutic target for breast cancer. Methods Publicly available breast cancer datasets analyses and Kaplan-Meier survival analyses were performed to reveal the expression and clinical relevance of atypical CDKs in breast cancer. CDK16 protein expression was further examined by immunohistochemical and immunoblot analyses of clinical samples. Cell proliferation was measured by colony formation and MTT analyses. Cell cycle and apoptosis were examined by fluorescence-activated cell sorting (FACS) analysis. Wound-healing and trans-well invasion assays were conducted to test cell migration ability. The functions of CDK16 on tumorigenesis and metastasis were evaluated by cell line-derived xenograft, patient-derived organoid/xenograft, lung metastasis and systemic metastasis mouse models. Transcriptomic analysis was performed to reveal the potential molecular mechanisms involved in the function of CDK16. Pharmacological inhibition of CDK16 was achieved by the small molecular inhibitor rebastinib to further assess the anti-tumor utility of targeting CDK16. Results CDK16 is highly expressed in breast cancer, particularly in triple-negative breast cancer (TNBC). The elevated CDK16 expression is correlated with poor outcomes in breast cancer patients. CDK16 can improve the proliferation and migration ability of TNBC cells in vitro, and promote tumor growth and metastasis of TNBC in vivo. Both genetic knockdown and pharmacological inhibition of CDK16 significantly suppress the tumor progression of TNBC. Mechanistically, CDK16 exerts its function by phosphorylating protein regulator of cytokinesis 1 (PRC1) to regulate spindle formation during mitosis. Conclusion CDK16 plays a critical role in TNBC and is a novel promising therapeutic target for TNBC.

Although Ru(II)-complex-based bulk nanomaterials have received considerable attention in electrochemiluminescent (ECL) assays owing to their strong ECL signals, the ECL efficiency of these nanomaterials was quite low since the bulk nanomaterials brought about a serious inner filter effect and excess inactive emitters. Herein, hollow porous polymeric nanospheres of a self-enhanced ruthenium complex (abbreviated as Ru-HPNSs) were prepared with a polyethylenimine-ruthenium complex precursor to greatly decrease the inner filter effect and minimize inactive emitters, which significantly improved the ECL efficiency. On the basis of the novel Ru-HPNSs as efficient ECL tags and target-catalyzed hairpin hybridization as signal amplification strategy, an ultrasensitive ECL aptasensor was constructed for the detection of mucin 1 (MUC1), which showed excellent linear response to a concentration variation from 1.0 fg/mL to 100 pg/mL with the limit of detection down to 0.31 fg/mL. It is worth mentioning that this work opened a new avenue for developing high-performance ECL nanomaterials as well as ultrasensitive ECL biosensors for clinical and biochemical analysis. [ABSTRACT FROM AUTHOR]

On the basis of a novel target-cycling synchronized rolling circle amplification (RCA) as a signal amplification strategy and in situ electrochemical generation of silver nanoclusters (Ag NCs) as signal probes, an ultrasensitive and simple electrochemiluminescence (ECL) biosensor was proposed for microRNA (miRNA) detection. It was worth mentioning that the circular template was subtly designed to consist of a guanine-rich (G-rich) region and a binding region for realizing target-cycling synchronized RCA In the presence of target miR-21, the binding region hybridized with the primer and the target miR-21 to form a ternary "P" junction structure, and then the RCA was triggered from the 3'-end of the primer. Along with the proceeding of RCA the target miR-21 was released and participated into another trigger of the RCA On account of the G-rich region in the circular template, the product DNA of the target-cycling synchronized RCA possessed tandem periodic cytosine-rich (C-rich) sequences, which acted as ligands to further in situ electrochemically generate silver nanodusters (Ag NCs) as ECL signal probes. As expected, the obtained ECL intensity dependent on the amount of the Ag NCs, which was positively related to the concentration of the target miR-21. The ECL assay for miR-21 detection demonstrated excellent linear response to a concentration variation from 100 aM to 100 pM and limit of detection down to 22 aM. [ABSTRACT FROM AUTHOR]

A target induced cycling strand displacement amplification (SDA) mediated by phi29 DNA polymerase (phi29) was first investigated and applied in a signal-off electrochemiluminescence (ECL) biosensor for microRNA (miRNA) detection. Herein, the target miRNA triggered the phi29-mediated SDA which could produce amounts of single-stranded DNA (assistant probe) with accurate and comprehensive nucleotide sequence. Then, the assistant probe hybridized with the capture probe and the ferrocene-labeled probe (Fc-probe) to form a ternary "Y" structure for ECL signal quenching by ferrocene. Therefore, the ECL intensity would decrease with increasing concentration of the target miRNA, and the sensitivity of biosensor would be promoted on account of the efficient signal amplification of the target induced cycling reaction. Besides, a self-enhanced Ru(ll) ECL system was designed to obtain a stable and strong initial signal to further improve the sensitivity. The ECL assay for miRNA-21 detection is developed with excellent sensitivity of a concentration variation from 10 aM to 1.0 pM and limit of detection down to 3.3 aM. [ABSTRACT FROM AUTHOR]