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With advances in technology, diagnostic techniques have become more sophisticated and efficient at detecting biomarkers rapidly. Biomarkers such as microRNA (miRNA), which exhibit exceptional specificity and sensitivity compared with other biomarkers, have garnered particular interest. Composed of 21–24 nucleotides, miRNAs constitute a noncoding RNA group that regulates gene expression, immune system activation, apoptosis, and other cellular processes; hence, they are frequently used as biomarkers for various diseases. This has sparked significant interest regarding the identification of the specific miRNAs implicated in many diseases. Presently, miRNA detection methods include northern blots, reverse transcription-quantitative polymerase chain reaction, and next-generation sequencing. While these methods are all sensitive, they are time-consuming, complex, and expensive, which renders them unsuitable for on-site detection. Surface-enhanced Raman scattering (SERS) can overcome these limitations to enable the sensitive and rapid detection of miRNA. This technique amplifies Raman signals, with signal enhancement levels changing sensitively depending on the distance between the target molecule and substrate. Therefore, this review covers the principle of SERS as a method for detecting miRNAs using nanomaterials, along with examples of nanomaterials and SERS applications. Based on the available literature, SERS is anticipated to enable the convenient, early diagnosis of various diseases, potentially lowering mortality rates. This review could therefore contribute significantly to the advancement of medical and diagnostic technologies. [ABSTRACT FROM AUTHOR]

Biohybrid robots have been developed for biomedical applications and industrial robotics. However, the biohybrid robots have limitations to be applied in neurodegenerative disease research due to the absence of a central nervous system. In addition, the organoids‐on‐a‐chip has not yet been able to replicate the physiological function of muscle movement in the human motor system, which is essential for evaluating the accuracy of the drugs used for treating neurodegenerative diseases. Here, a human motor system‐based biohybrid robot‐on‐a‐chip composed of a brain organoid, multi‐motor neuron spheroids, and muscle bundle on solid substrateis proposed to evaluate the drug effect on neurodegenerative diseases for the first time. The electrophysiological signals from the cerebral organoid induced the muscle bundle movement through motor neuron spheroids. To evaluate the drug effect on Parkinson's disease (PD), a patient‐derived midbrain organoid is generated and incorporated into a biohybrid robot‐on‐a‐chip. The drug effect on PD is successfully evaluated by measuring muscle bundle movement. The muscle bundle movement of PD patient‐derived midbrain organoid‐based biohybrid robot‐on‐a‐chip is increased from 4.5 ± 0.99 µm to 18.67 ± 2.25 µm in response to levodopa. The proposed human motor system‐based biohybrid robot‐on‐a‐chip can serve as a standard biohybrid robot model for drug evaluation. [ABSTRACT FROM AUTHOR]

In the context of virus outbreaks, the need for early and accurate diagnosis has become increasingly urgent. In addition to being crucial for effective disease control, timely and precise detection of viral infections is also necessary for the implementation of essential public health measures, especially during pandemics. Among these measures, point-of-care testing (POCT) stands out as a powerful approach with the potential to revolutionize the landscape of viral diagnosis. In this study, we developed a one-pot clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a-based viral DNA detection system tailored for POCT; this method utilizes multi-enzyme-modified Au@Fe3O4 nanoparticles. As an alternative to nucleic acid amplification, our method uses single-stranded DNA elongation to facilitate multi-enzyme modification; this guarantees heightened sensitivity and expedites the diagnostic process. We achieved a satisfactory limit of detection of 0.25 nM, demonstrating the remarkable sensitivity of the method without the need for sophisticated equipment. The incorporation of Au@Fe3O4 magnetic nanoparticles facilitates sample separation, further streamlining the workflow and reinforcing the simplicity of our method. This integrated approach offers a practical solution for sensitive viral DNA detection in POCT scenarios, advancing the field of rapid and accurate diagnostics. [ABSTRACT FROM AUTHOR]

A high-performance single-phase online uninterruptible power supply (UPS) is proposed. The UPS is composed of a three-leg-type converter which operates as a battery charger and an inverter. The first leg is controlled to charge the battery, and the third leg is controlled to make the output voltage. The common leg is controlled in line frequency. The charger and the inverter are controlled independently. The charger has the capability of power-factor correction while charging a battery. The inverter regulates output voltage and limits output current under an impulsive load. The three-leg-type converter reduces the number of switching devices. As a result, the system has less power loss and a low-cost structure. In the determination of the charger voltage, the nominal voltage is derived using the feedback linearization concept and then a perturbed voltage is determined for the reactive power control. The disturbance of input voltage is detected using a fast sensing technique of the input voltage. Experimental results obtained with a 3-VA prototype show a normal efficiency of over 87% and an input power factor of over 99%. Index Terms--Battery charger, power-factor correction (PFC), uninterruptible power supply (UPS).