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8 W m-2 that can drive wearable electronics. Besides, the Bio-TENG can work as artificial electronic skin for touch/pressure perception, and also for wirelessly controlling Internet of Things as a switch.Nitric oxide (NO) can delicately tune the cellular signaling pathway and plays crucial roles in physiological processes. It is of profound significance to engineer a smart and efficient artificial platform to detect NO, especially for the tracking of living cell released NO. Herein, a switchable nitric oxide responsive nanochannel analysis platform is constructed by introducing a reversible N-nitrosation reaction of rhodamine 6G (R6G) into the artificial nanochannels. By virtue of the distinctive design, ionic current signal can handily realize reversible switching between “on” and “off” state in the presence of NO and UV light, and the system featured high stability and reproducibility. The R6G-immobilized nanochannels exhibited high sensitivity and selectivity towards NO over other gas molecules and biomolecules by ion current rectification (ICR) test. More intriguingly, the system also showed good performances for in situ monitoring of NO released from human umbilical vein endothelial cells (HUVECs), suggesting the as-constructed nanochannels can act as a versatile NO gas valve for nanoelectronic logic devices. This work purposes a novel method for the rapid and noninvasive detection of bioactive gas and holds great promise for biomedical research, disease diagnosis and treatment.Peroxidase-like DNAzymes have been extensively used to replace horseradish peroxidase (HRP) for developing biosensors for signal amplification. However, the background activity from the cofactor (i.e., free hemin) has limited the sensitivity of such sensors. Herein, we aim to find an inhibitor for hemin to suppress the background signal, and a classic split DNAzyme-based sensor was used to detect a complementary DNA oligonucleotide. After screening a series of dyes, SYBR Green I (SG, one of the DNA stanning dyes) was selected for suppressing the background. Simply by adding 0.84 μM SG, the background from 50 nM hemin was suppressed over 30-fold. The suppression was caused by the interaction between SG and hemin. In the presence of the target DNA, the formed duplex region and G-quadruplex structure can better bind SG and hemin respectively, thus preventing the interaction between them and showing a high activity of the DNAzyme. The optimized sensor showed a detection limit of 3.8 pM for the target DNA (p53 gene). In addition, the backgrounds from chemiluminescence, colorimetric and fluorescence sensing modes can all be reduced by adding SG to the split DNAzyme system. The suppression of the background of peroxidase DNAzymes is a critical step towards practical use of related biosensors.Diabetic retinopathy (DR) is the leading global cause of blindness in the working-age population. Early diagnosis and intervention can effectively reduce the risk for blindness. However, the current diagnostic methods in clinical practice remain constrained by nonquantitative examinations and individual ophthalmologists’ experiences. Sensitive, specific and accurate detection of DR-specific biomarkers is an important approach to achieve its early and rapid diagnosis. In this study, a high-affinity aptamer APT12TM that specifically binds to the tear-derived DR biomarker lipocalin 1 was obtained. The aptamer APT12TM can be folded into a stable B-DNA structure, and its strong interaction with LCN 1, including hydrogen bonding and hydrophobic interactions, is an important factor for targeted recognition and high-affinity binding. Nintedanib A G-rich DNA fragment was further assembled at both ends of the aptamer APT12TM, and the B-DNA form was successfully converted into a parallel G-quadruplex. Most importantly, LCN 1 could induce further transformation of the G-quadruplex structure. Therefore, a fluorescent aptasensor based on G-quadruplex-assisted structural transformation was developed through the Thioflavin T mediator. The aptasensor exhibited a broad detection window from 0.25 to 1000 nM LCN 1, with a limit of detection of 0.2 nM. Furthermore, the aptasensor was applied to LCN 1 detection in artificial tear samples and displayed good reproducibility and stability. These results show that the developed aptasensor has significant potential for sensitive, specific and convenient detection of the DR-specific biomarker LCN 1.Drug abuse is a global problem, requiring an interdisciplinary approach. Discovery, production, trafficking, and consumption of illicit drugs have been constantly growing, leading to heavy consequences for environment, human health, and society in general. Therefore, an urgent need for rapid, sensitive, portable and easy-to-operate detection methods for numerous drugs of interest in diverse matrices, from police samples, biological fluids and hair to sewage water has risen. Electrochemical sensors are promising alternatives to chromatography and spectrometry. Last decades, electrochemical sensing of illegal drugs has experienced a very significant growth, driven by improved transducers and signal amplifiers helping to improve the sensitivity and selectivity. The present review summarizes recent advances (last 10 years) in electrochemical detection of the most prevailing illicit drugs (such as cocaine, heroin, and (meth)amphetamine), their precursors and derivatives in different matrices. Various electrochemical sensors making use of different transducers with their (dis)advantages were discussed, and their sensitivity and applicability were critically compared. In those cases where natural or synthetic recognition elements were included in the sensing system to increase specificity, selected recognition elements, their immobilization, working conditions, and analytical performance were discussed. Finally, an outlook is presented with suggestions and recommendations for future developments.Cholinesterases (ChEs) are important indicators of neurological disease, hepatocellular carcinoma, and organophosphate poisoning. In this work, a MnO2 switch-bridged DNA walker was developed for ultrasensitive sensing of ChEs activity. The fuel strands loaded MnO2 switch was designed to bridge the hydrolysis activity of ChEs and the running of the DNA walker. Under the action of ChE, the substrate butyrylcholine is first catalytically hydrolyzed to thiocholine, which then mediates MnO2 nanosheet reduction to Mn2+, releasing the fuel strands into solution. The fuel strands as substitute targets then trigger the continuous operation of DNA walker with the aid of Mn2+, generating detectable fluorescence responses. The detection of ChE activity is converted to DNA detection in this method. Benefited from the robust operation and amplification effect of DNA walker, a wide linear range between the BChE activity and fluorescence intensity of nearly six orders of magnitude (1000-0.005 U/mL) and a limit of detection as low as 0.0008 U/mL are achieved. This allows the direct determination of BChE activity in clinical serum samples without any pretreatments. Moreover, the proposed method has remarkable capabilities for inhibitor (organophosphorus pesticide) screening and quantification, and organophosphorus pesticide detection in real samples is also achieved. Therefore, the MnO2 switch-bridged DNA walker represents a powerful tool for ultrasensitive sensing of ChEs and organophosphorus pesticides, and has great application potential in clinical diagnosis, therapeutics, and drug screening.The rapid growth of in vitro nucleic acid replication has offered a powerful tool for clinical diagnosis, food safety detection and environmental monitorning. Successful implementation of various isothermal nucleic acid amplification methods enables rapid replication of target sequences without the participant of a thermal cycler. Point-of-need analysis possesses great superiorities in user-friendly, instant results analysis, low manufacturing, and consumable costs. To meet the great challenge of point-of-need analysis, developing simple and rapid visual methods becomes crucial. Submicro- and nanomaterials possess unique surface properties, which enables their rapid response to DNA amplicons. Their unique optical, magnetic, catalytic, and other physical/chemical properties have been frequently employed for the visual detection of in vitro nucleic acid replications. Herein, we aim to review the submicro- and nanomaterials-based visual methods for detection of nucleic acid amplification. The visual methods are classified according to the designing strategies (e.g. LSPR, bridging flocculation, luminescence, catalytic reaction, separation, etc.). The basic principles, merits and drawbacks of each strategy are described. The application in analysis of nucleic acid targets and non-nucleic acid targets are discussed. The main challenges and future research directions are also highlighted in this rapidly emerging field.Studies have linked the diffusion of medical innovations to a distinctive professional project. In this project, physician specialists embrace an innovation, work to advance its successes, link these successes to their core-skill definitions, and use this linkage in boundary work to promote their professional identities and expand their jurisdictions, largely by distinguishing themselves from others within their profession. Drawing from a case study examining the diffusion of laparoscopic sterilization procedures in American ob/gyn, this article suggests that a specific type of revitalization movement may serve as an unwitting catalyst for these innovation/professional projects. To promote a”new”specialist identity, this revitalization movement employs foil labeling in its boundary work that dishonors, not outsiders, but established clinicians within the specialty. This dishonoring motivates these clinicians, as a generational cohort, to embrace radical innovations and break established work patterns. Radical innovations may spread across medical fields, not so much through projects bonding professionals to a unified collective, but through reactive projects within highly specialized fields prone to fragment along generational lines.Women experiencing poverty and women of color disproportionately experience intimate partner violence (IPV) victimization. Economic policies targeting women at this intersection of poverty and IPV, including Temporary Assistance for Needy Families (TANF), Minimum Wage (MW), and Earned Income Tax Credits (EITCs), may be powerful violence prevention tools. Using data from waves 1 (1998-2000) through 4 (2007-2010) of the U.S.-based Fragile Families and Child Well-being (FFCW) birth cohort study, we apply a difference-in-difference (DD) study design to estimate both the overall and race-specific effects of state-level economic policies on non-physical IPV and several intermediate outcomes. In DD models analyzing the difference in violence outcomes by intervention group (i.e., TANF exposure based on women’s educational attainment, ≤high school vs >high school) and by race (African American (AA) vs White) few state-level TANF policies were associated with IPV victimization and the MW had no differential effect, but the refundable EITC was protective against IPV.