Lateral flow strip assay of a gene segment in the COVID-19 virus with combined dual readout mode and preliminary multisite hybrid chain reaction amplification.

The past and present scenario of COVID-19 has revealed the necessity of simple point-of-care tests. When combined with the great advantages of amplification, lateral flow assay nucleic acid analysis represents a more sensitive molecular diagnostic technique compared to universal protein analysis. Room temperature operation, an enzyme-free nature, and in situ elongation make hybrid chain reaction amplification (HCR) a good candidate for amplified combined lateral flow assays (LFAs). Since dual modes of detection can not only satisfy different application scenarios, but also reduce the false-negative rate, in this paper, visual and fluorescent detection based on labelling with colloidal gold nanoparticles and fluorescence labelling were incorporated into a HCR integrated with a LFA. The detection assay was finished in 30 minutes. The linear relationship between the signal and the concentration of the characteristic segment in the COVID-19 ORF gene was demonstrated. The obtained detection limits of as low as 10 fM (6.02 × 103 copies per mL) and 1 fM (6.02 × 102 copies per mL), respectively, were comparable with those in the literature. The multi-site HCR amplification integrated with LFA of a 1053 bp nucleic acid chain was also preliminarily studied, and tri-site amplification was found to exhibit higher signal intensity than single-site amplification. This study provides a promising strategy for simple, sensitive, and wide-ranging detection of pathogenic bacteria.

Effect of bladder emptying status on the ureteral access sheath insertion resistance and following ureteral injury in RIRS: a prospective randomized controlled trial in academic hospital.

PURPOSE: To evaluate the effect of bladder emptying status on the ureteral access sheath (UAS) insertion resistance and following ureteral injury. METHODS: Eighty patients were enrolled and randomly divided into bladder emptying group and control group before UAS placement. A digital force gauge (Imada Z2-50N) was used to measure the resistance during the UAS insertion. The ureteral injury was evaluated and graded with Post-Ureteroscopic Lesion Scale (PULS) system at the end of procedure. The mean resistance, maximum resistance in different ureteral segments, and ureteral injury were compared between the two groups. RESULTS: The mean resistance (3.12 ± 0.49 vs. 4.28 ± 0.52 N, P < 0.001), maximum resistance in the whole procedure (5.17 ± 0.72 vs. 6.39 ± 0.96 N, P < 0.001) and distal ureter (3.07 ± 0.75 vs. 6.18 ± 1.17 N, P < 0.001) in the bladder emptying group were significantly lower when compared to the control group. In subgroup analysis, the similar result was also noted in patients with BMI ≥ 25 when compared to patients with BMI < 25, while there was no significant difference between men and women, age ≥ 50 years versus age < 50 years. The incidence of PULS 1-2 ureteral injury in the bladder emptying group was lower than the control group (35% vs. 55%, P = 0.045). The ureteral injury in distal ureteral was less frequently noted in bladder emptying group than the control group (22.5% vs. 55%, P = 0.006); however, there was no significant difference in middle and upper ureter (P > 0.05). CONCLUSION: Emptying the bladder before UAS insertion can effectively reduce the UAS insertion resistance and the risk of distal ureteral injury in RIRS.

Wearable Continuous Blood Pressure Monitoring Devices Based on Pulse Wave Transit Time and Pulse Arrival Time: A Review.

Continuous blood pressure (BP) monitoring is of great significance for the real-time monitoring and early prevention of cardiovascular diseases. Recently, wearable BP monitoring devices have made great progress in the development of daily BP monitoring because they adapt to long-term and high-comfort wear requirements. However, the research and development of wearable continuous BP monitoring devices still face great challenges such as obvious motion noise and slow dynamic response speeds. The pulse wave transit time method which is combined with photoplethysmography (PPG) waves and electrocardiogram (ECG) waves for continuous BP monitoring has received wide attention due to its advantages in terms of excellent dynamic response characteristics and high accuracy. Here, we review the recent state-of-art wearable continuous BP monitoring devices and related technology based on the pulse wave transit time; their measuring principles, design methods, preparation processes, and properties are analyzed in detail. In addition, the potential development directions and challenges of wearable continuous BP monitoring devices based on the pulse wave transit time method are discussed.

Recent Progress in Long-Term Sleep Monitoring Technology.

Sleep is an essential physiological activity, accounting for about one-third of our lives, which significantly impacts our memory, mood, health, and children's growth. Especially after the COVID-19 epidemic, sleep health issues have attracted more attention. In recent years, with the development of wearable electronic devices, there have been more and more studies, products, or solutions related to sleep monitoring. Many mature technologies, such as polysomnography, have been applied to clinical practice. However, it is urgent to develop wearable or non-contacting electronic devices suitable for household continuous sleep monitoring. This paper first introduces the basic knowledge of sleep and the significance of sleep monitoring. Then, according to the types of physiological signals monitored, this paper describes the research progress of bioelectrical signals, biomechanical signals, and biochemical signals used for sleep monitoring. However, it is not ideal to monitor the sleep quality for the whole night based on only one signal. Therefore, this paper reviews the research on multi-signal monitoring and introduces systematic sleep monitoring schemes. Finally, a conclusion and discussion of sleep monitoring are presented to propose potential future directions and prospects for sleep monitoring.

Recent Progress of Tactile and Force Sensors for Human-Machine Interaction.

Human-Machine Interface (HMI) plays a key role in the interaction between people and machines, which allows people to easily and intuitively control the machine and immersively experience the virtual world of the meta-universe by virtual reality/augmented reality (VR/AR) technology. Currently, wearable skin-integrated tactile and force sensors are widely used in immersive human-machine interactions due to their ultra-thin, ultra-soft, conformal characteristics. In this paper, the recent progress of tactile and force sensors used in HMI are reviewed, including piezoresistive, capacitive, piezoelectric, triboelectric, and other sensors. Then, this paper discusses how to improve the performance of tactile and force sensors for HMI. Next, this paper summarizes the HMI for dexterous robotic manipulation and VR/AR applications. Finally, this paper summarizes and proposes the future development trend of HMI.

Development and internal validation of a prediction model to evaluate the risk of severe hemorrhage following mini-percutaneous nephrolithotomy.

PURPOSE: To develop a new prediction model for assessing the severe hemorrhage events in post mini-percutaneous nephrolithotomy (mini-PCNL) patients and internally validate it, thus to guide decision making in clinical practice. METHODS: The patients who underwent mini-PCNL were retrospectively reviewed. Potential risk factors were included as prediction variables for multivariate logistic regression analysis to identify independent risk factors, and prediction model was constructed. The predictive ability of the model was evaluated using the Concordance index (C-index) and Brier score. Bootstrapping resampling technique was used to perform internal validation. The related packages in R were used to generate the web application based on the prediction model. RESULTS: Multiple-tract was the strongest predictor of severe hemorrhage following mini-PCNL. Other risk factors were none or mild hydronephrosis, congenital anomalies of urinary system, urinary tract infection, operation time and stone peak Hounsfield unit. A prediction model was constructed to assess the probability of severe hemorrhage after mini-PCNL. The C-index and Brier score were 0.731 and 0.093, respectively after correcting for optimism, which signified the excellent discrimination and calibration. CONCLUSION: A new prediction model was developed to estimate risk of severe hemorrhage after mini-PCNL. It had been internally validated with good discrimination and calibration. The prediction model might be beneficial for endourologists in surgical decision-making and risk aversion.

Translation and validation of the Chinese version of Wisconsin Stone Quality of Life questionnaire in patients with kidney stones.

BACKGROUND: Wisconsin Stone Quality of Life (WISQOL) has been designed specifically for patients with kidney stones. The present study aimed to develop the Chinese version of WISQOL and reach its validation. METHODS: The WISQOL was translated into Chinese following a standard procedure. Kidney stone patients admitted for surgical treatment were enrolled and fulfilled both WISQOL and SF-36 on the admission day and at one month postoperatively. The internal consistency, inter-domain correlation and convergent validity were analyzed. RESULTS: One hundred twenty-four 124 males and 76 females were enrolled. The total WISQOL Score and SF-36 had significant correlation both preoperatively (r=0.772, P<0.01) and postoperatively (r=0.639, P<0.01). The internal consistency of the Chinese version WISQOL's different domains ranged from 0.766 to 0.959. The value of Spearman rank correlation to assess the convergent validity of different domains ranged from 0.444 to 0.687. The postoperative WISQOL raised about 20% showing a better quality of life. CONCLUSIONS: The Chinese version of WISQOL questionnaire was a reliable tool to evaluate the health quality of life in Chinese-speaker patients with kidney stones. To evaluate its test-retest reliability, reliability and validity in a longer term, further studies are required.

Electrooculography and Tactile Perception Collaborative Interface for 3D Human-Machine Interaction.

The human-machine interface (HMI) previously relied on a single perception interface that cannot realize three-dimensional (3D) interaction and convenient and accurate interaction in multiple scenes. Here, we propose a collaborative interface including electrooculography (EOG) and tactile perception for fast and accurate 3D human-machine interaction. The EOG signals are mainly used for fast, convenient, and contactless 2D (XY-axis) interaction, and the tactile sensing interface is mainly utilized for complex 2D movement control and Z-axis control in the 3D interaction. The honeycomb graphene electrodes for the EOG signal acquisition and tactile sensing array are prepared by a laser-induced process. Two pairs of ultrathin and breathable honeycomb graphene electrodes are attached around the eyes for monitoring nine different eye movements. A machine learning algorithm is designed to train and classify the nine different eye movements with an average prediction accuracy of 92.6%. Furthermore, an ultrathin (90 µm), stretchable (∼1000%), and flexible tactile sensing interface assembled by a pair of 4 × 4 planar electrode arrays is attached to the arm for 2D movement control and Z-axis interaction, which can realize single-point, multipoint and sliding touch functions. Consequently, the tactile sensing interface can achieve eight directions control and even more complex movement trajectory control. Meanwhile, the flexible and ultrathin tactile sensor exhibits an ultrahigh sensitivity of 1.428 kPa-1 in the pressure range 0-300 Pa with long-term response stability and repeatability. Therefore, the collaboration between EOG and the tactile perception interface will play an important role in rapid and accurate 3D human-machine interaction.

Two-stage amplification of an ultrasensitive MXene-based intelligent artificial eardrum.

We report an artificial eardrum using an acoustic sensor based on two-dimensional MXene (Ti3C2Tx), which mimics the function of a human eardrum for realizing voice detection and recognition. Using MXene with a large interlayer distance and micropyramid polydimethylsiloxane arrays can enable a two-stage amplification of pressure and acoustic sensing. The MXene artificial eardrum shows an extremely high sensitivity of 62 kPa-1 and a very low detection limit of 0.1 Pa. Notably, benefiting from the ultrasensitive MXene eardrum, the machine-learning algorithm for real-time voice classification can be realized with high accuracy. The 280 voice signals are successfully classified for seven categories, and a high accuracy of 96.4 and 95% can be achieved by the training dataset and the test dataset, respectively. The current results indicate that the MXene artificial intelligent eardrum shows great potential for applications in wearable acoustical health care devices.

Development of high-resolution multidimensional native protein microfluidic chip electrophoresis fingerprinting and its application in the quick analysis of unknown microorganisms.

The unascertained, constant mutation and emergence of new types of microorganisms present significant challenges to their detection. Differing from the focus on the limited local 16S rRNA gene or protein markers, characteristic whole fingerprint technologies at the omic level are particularly suitable for unknown analytes since accurate knowledge about the constituents is not necessarily required. Herein, through a combination of several innovative strategies, including pure water isotachophoresis integrated (2 + 1)D electrophoresis, inversion-funnel peak stacking channel geometry and COMSOL computer-aided fluid simulation, high-resolution whole protein 2D native microfluidic chip electrophoresis was achieved within less than 1 min. The highest ever reported peak capacity for native 2D chip electrophoresis was obtained. Furthermore, taking Escherichia coli, Staphylococcus aureus, and Bacillus subtilis as model analytes without protein biomarker information, the feasibility of the identification and semiqualification of unknown microbes in pure or mixed samples was explored with the utilisation of original algorithms, including SIFT feature abstraction and a global information entropy combined support vector machine. As such, the multidisciplinary cooperation in the present study demonstrates monstrated promising prospects for microfluidic chip electropherogram fingerprint-based quick microorganism assays, biointeraction studies, and drug screenings, even if the analytes are not fully ascertained.

Retrograde intrarenal surgery in lateral position for lower pole stone: an initial experience from Single Academic Hospital.

Retrograde intrarenal surgery (RIRS) was generally challenging in management of lower pole stone (LPS) since the unfavorable anatomy. Theoretically, LPS was prone to fall out and down to renal pelvis when patients turned to lateral position, thus to facilitate lithotripsy. The aim of the present study was to report our initial experience of RIRS in lateral position for LPS. From January 2020 to February 2021, 21 patients with LPS received RIRS in lateral position. The intraoperative finding, operation time, complications and stone-free rate (SFR) were recorded and analyzed. The mean stone size was 16.7 ± 2.4 mm, multiple stones in lower pole were noted in 38.1% (8/21) cases. The mean infundibular-pelvic angle (IPA) was 35.2 ± 6.9°, IPA less than 30° was noted in six cases (28.6%, 6/21). Mean operation time was 43.5 ± 6.3 min. Obvious stone fragments dropping from the lower calyx to renal pelvis during the lithotripsy were noted in 17 cases (81.0%). Only one case (4.8%) suffered postoperative fever (Clavien I), no severe complication (> Clavien II) was noted. Hospital stay was 1.1 ± 0.3 days, the SFR in postoperative 1 month was 85.7%. LPS was prone to fall out and down to renal pelvis when patients in lateral position, thus to facilitate the lithotripsy. RIRS in lateral position was feasible for the management of LPS; however, RCT with large sample was required to certify our initial finding.

Microfluidic chip-based long-term preservation and culture of engineering bacteria for DNA damage evaluation.

Understanding the effects of long-term exposure to space environment is paramount to maintaining the safety, health of astronauts. The physical dosimeters currently used on the space station cannot be used to assess the physiological effects of radiation. Moreover, some developed biological methods are time-consuming and passive and cannot be used for active and real-time detection of the physiological effects of radiation in space environment. Here, the SOS promoter: recA-eGFP genetic engineering bacteria was constructed and characterized, and DNA damage effects of some chemical reagents and radiation were evaluated. The results indicated the constructed engineering bacteria can distinguish DNA damage reagents from non-damage reagents and have a good dose-fluorescence effect against Co-60 radiation with the detection limit of 0.64 Gy; in order to overcome the restriction of long-term preservation of bacteria in space environment, the bacteria were freeze-dried, and the protectants were optimized, the storage time of bacteria under dry conditions was explored by accelerated storage experiment. Finally, a microfluidic chip was designed and fabricated for freeze-drying genetic engineering bacteria recovery, culture, and analysis in space environment. This study can provide support for the establishment of on-orbit radiation damage risk monitoring and early warning and can provide basic data for maintaining the health and performance of astronauts on long-term space flight missions. Moreover, the technique developed herein has a great potential to be used as a powerful tool for efficiently screening various radioactive substance, toxic chemicals, drugs, etc. KEY POINTS: • The SOS promoter: recA-eGFP genetic engineering bacteria was successfully constructed, which can distinguish DNA damage reagents from non-damage reagents and possess a good dose-effect relationship against Co-60 radiation. • The bacteria were freeze-dried to overcome the restriction of long-term preservation of bacteria in space environment, and protectants were optimized, and the survival rate of freeze-dried engineering bacteria can be predicted based on the results of accelerated storage experiment. • Microfluidic chip-based culture platform was successfully designed, fabricated, and used for freeze-drying genetic engineering bacteria recovery, culture, and analysis.

An Ultra-Sensitive and Multifunctional Electronic Skin with Synergetic Network of Graphene and CNT.

Electronic skin (e-skin) has attracted tremendous interest due to its diverse potential applications, including in physiological signal detection, health monitoring, and artificial throats. However, the major drawbacks of traditional e-skin are the weak adhesion of substrates, incompatibility between sensitivity and stretchability, and its single function. These shortcomings limit the application of e-skin and increase the complexity of its multifunctional integration. Herein, the synergistic network of crosslinked SWCNTs within and between multilayered graphene layers was directly drip coated onto the PU thin film with self-adhesion to fabricate versatile e-skin. The excellent mechanical properties of prepared e-skin arise from the sufficient conductive paths guaranteed by SWCNTs in small and large deformation under various strains. The prepared e-skin exhibits a low detection limit, as small as 0.5% strain, and compatibility between sensitivity and stretchability with a gauge factor (GF) of 964 at a strain of 0-30%, and 2743 at a strain of 30-60%. In physiological signals detection application, the e-skin demonstrates the detection of subtle motions, such as artery pulse and blinking, as well as large body motions, such as knee joint bending, elbow movement, and neck movement. In artificial throat application, the e-skin integrates sound recognition and sound emitting and shows clear and distinct responses between different throat muscle movements and different words for sound signal acquisition and recognition, in conjunction with superior sound emission performance with a sound spectrum response of 71 dB (f = 12.5 kHz). Overall, the presented comprehensive study of novel materials, structures, properties, and mechanisms offers promising potential in physiological signals detection and artificial throat applications.

Programmable Sensitivity Screening of Strain Sensors by Local Electrical and Mechanical Properties Coupling.

Owing to the canonical trade-off between the gauge factor and the working range, there is an emergent need for strain sensors with customizable sensitivity for various applications of different deformation ranges. However, current optimization strategies typically allow possessing either, not both, high-sensing performance or customizable sensing performance. Here, a laser-programmed heterogeneous strain sensor featured locally coupled electrical and mechanical properties (named an LCoup sensor) is developed to access customized sensor performance. Coupled electromechanical properties enable the applied strain to be mainly experienced by the higher sensitivity regions when stretched. By optimizing the parameters of laser processes, the gauge factor can systematically screen within 2 orders of magnitude (from 7.8 to 266.6) while maintaining good stretchability (50%). To prove the potential in human-machine interaction, the real-time monitoring and recognition of set hand gestures (left-click, right-click, and double-click) are demonstrated, representing the traditional input patterns of the computer mouse. Multiscale programming of material properties can further achieve excellent and tailored device performances, offering more opportunities for the design of a broad range of flexible electronics.

A Low-Cost, Portable, and Wireless In-Shoe System Based on a Flexible Porous Graphene Pressure Sensor.

Monitoring gait patterns in daily life will provide a lot of biological information related to human health. At present, common gait pressure analysis systems, such as pressure platforms and in-shoe systems, adopt rigid sensors and are wired and uncomfortable. In this paper, a biomimetic porous graphene-SBR (styrene-butadiene rubber) pressure sensor (PGSPS) with high flexibility, sensitivity (1.05 kPa-1), and a wide measuring range (0-150 kPa) is designed and integrated into an insole system to collect, process, transmit, and display plantar pressure data for gait analysis in real-time via a smartphone. The system consists of 16 PGSPSs that were used to analyze different gait signals, including walking, running, and jumping, to verify its daily application range. After comparing the test results with a high-precision digital multimeter, the system is proven to be more portable and suitable for daily use, and the accuracy of the waveform meets the judgment requirements. The system can play an important role in monitoring the safety of the elderly, which is very helpful in today's society with an increasingly aging population. Furthermore, an intelligent gait diagnosis algorithm can be added to realize a smart gait monitoring system.

Multifunctional Graphene Microstructures Inspired by Honeycomb for Ultrahigh Performance Electromagnetic Interference Shielding and Wearable Applications.

High-performance electromagnetic interference (EMI) shielding materials with ultralow density, excellent flexibility, and good mechanical properties are highly desirable for aerospace and wearable electronics. Herein, honeycomb porous graphene (HPG) fabricated by laser scribing technology is reported for EMI shielding and wearable applications. Due to the honeycomb structure, the HPG exhibits an EMI shielding effectiveness (SE) up to 45 dB at a thickness of 48.3 µm. The single-piece HPG exhibits an ultrahigh absolute shielding effectiveness (SSE/t) of 240 123 dB cm2/g with an ultralow density of 0.0388 g/cm3, which is significantly superior to the reported materials such as carbon-based, MXene, and metal materials. Furthermore, MXene and AgNWs are employed to cover the honeycomb holes of the HPG to enhance surface reflection; thus, the SSE/t of the HPG/AgNWs composite membrane can reach up to 292 754 dB cm2/g. More importantly, the HPG exhibits excellent mechanical stability and durability in cyclic stretching and bending, which can be used to monitor weak physiological signals such as pulse, respiration, and laryngeal movement of humans. Therefore, the lightweight and flexible HPG exhibits excellent EMI shielding performance and mechanical properties, along with its low cost and ease of mass production, which is promising for practical applications in EMI shielding and wearable electronics.