Scaling up of a Self-Confined Catalytic Hybridization Circuit for Robust microRNA Imaging.

The precise regulation of cellular behaviors within a confined, crowded intracellular environment is highly amenable in diagnostics and therapeutics. While synthetic circuitry system through a concatenated chemical reaction network has rarely been reported to mimic dynamic self-assembly system. Herein, a catalytic self-defined circuit (CSC) for the hierarchically concatenated assembly of DNA domino nanostructures is engineered. By incorporating pre-sealed symmetrical fragments into the preying hairpin reactants, the CSC system allows the hierarchical DNA self-assembly via a microRNA (miRNA)-powered self-sorting catalytic hybridization reaction. With minimal strand complexity, this self-sustainable CSC system streamlined the circuit component and achieved localization-intensified cascaded signal amplification. Profiting from the self-adaptively concatenated hybridization reaction, a reliable and robust method has been achieved for discriminating carcinoma tissues from the corresponding para-carcinoma tissues. The CSC-sustained self-assembly strategy provides a comprehensive and smart toolbox for organizing various hierarchical DNA nanostructures, which may facilitate more insights for clinical diagnosis and therapeutic assessment.

Compensation Method for Missing and Misidentified Skeletons in Nursing Care Action Assessment by Improving Spatial Temporal Graph Convolutional Networks.

With the increasing aging population, nursing care providers have been facing a substantial risk of work-related musculoskeletal disorders (WMSDs). Visual-based pose estimation methods, like OpenPose, are commonly used for ergonomic posture risk assessment. However, these methods face difficulty when identifying overlapping and interactive nursing tasks, resulting in missing and misidentified skeletons. To address this, we propose a skeleton compensation method using improved spatial temporal graph convolutional networks (ST-GCN), which integrates kinematic chain and action features to assess skeleton integrity and compensate for it. The results verified the effectiveness of our approach in optimizing skeletal loss and misidentification in nursing care tasks, leading to improved accuracy in calculating both skeleton joint angles and REBA scores. Moreover, comparative analysis against other skeleton compensation methods demonstrated the superior performance of our approach, achieving an 87.34% REBA accuracy score. Collectively, our method might hold promising potential for optimizing the skeleton loss and misidentification in nursing care tasks.

Engineering of a Self-Regulatory Bidirectional DNA Assembly Circuit for Amplified MicroRNA Imaging.

The engineering of catalytic hybridization DNA circuits represents versatile ways to orchestrate a complex flux of molecular information at the nanoscale, with potential applications in DNA-encoded biosensing, drug discovery, and therapeutics. However, the diffusive escape of intermediates and unintentional binding interactions remain an unsolved challenge. Herein, we developed a compact, yet efficient, self-regulatory assembly circuit (SAC) for achieving robust microRNA (miRNA) imaging in live cells through DNA-templated guaranteed catalytic hybridization. By integrating the toehold strand with a preblocked palindromic fragment in the stem domain, the proposed miniature SAC system allows the reactant-to-template-controlled proximal hybridization, thus facilitating the bidirectional-sustained assembly and the localization-intensified signal amplification without undesired crosstalk. With condensed components and low reactant complexity, the SAC amplifier realized high-contrast intracellular miRNA imaging. We anticipate that this simple and template-controlled design can enrich the clinical diagnosis and prognosis toolbox.

Monitoring of Sleep Breathing States Based on Audio Sensor Utilizing Mel-Scale Features in Home Healthcare.

Sleep-related breathing disorders (SBDs) will lead to poor sleep quality and increase the risk of cardiovascular and cerebrovascular diseases which may cause death in serious cases. This paper aims to detect breathing states related to SBDs by breathing sound signals. A moment waveform analysis is applied to locate and segment the breathing cycles. As the core of our study, a set of useful features of breathing signal is proposed based on Mel frequency cepstrum analysis. Finally, the normal and abnormal sleep breathing states can be distinguished by the extracted Mel-scale indexes. Young healthy testers and patients who suffered from obstructive sleep apnea are tested utilizing the proposed method. The average accuracy for detecting abnormal breathing states can reach 93.1%. It will be helpful to prevent SBDs and improve the sleep quality of home healthcare.

Tidal Volume Level Estimation Using Respiratory Sounds.

Respiratory sounds have been used as a noninvasive and convenient method to estimate respiratory flow and tidal volume. However, current methods need calibration, making them difficult to use in a home environment. A respiratory sound analysis method is proposed to estimate tidal volume levels during sleep qualitatively. Respiratory sounds are filtered and segmented into one-minute clips, all clips are clustered into three categories: normal breathing/snoring/uncertain with agglomerative hierarchical clustering (AHC). Formant parameters are extracted to classify snoring clips into simple snoring and obstructive snoring with the K-means algorithm. For simple snoring clips, the tidal volume level is calculated based on snoring last time. For obstructive snoring clips, the tidal volume level is calculated by the maximum breathing pause interval. The performance of the proposed method is evaluated on an open dataset, PSG-Audio, in which full-night polysomnography (PSG) and tracheal sound were recorded simultaneously. The calculated tidal volume levels are compared with the corresponding lowest nocturnal oxygen saturation (LoO2) data. Experiments show that the proposed method calculates tidal volume levels with high accuracy and robustness.

Comparison of the Efficacy of Different Surgical Approaches for Complicated Impacted Proximal Ureteral Calculi Based on a New Scoring Standard: A Matched-Pair Analysis.

Objective: To compare the clinical efficacy of ureteroscopic lithotripsy (URSL) and percutaneous nephrolithotomy (PCNL) in the treatment of complicated impacted proximal ureteral calculi using a new scoring standard. Methods: The data of 45 patients with complicated impacted proximal ureteral calculi (score ≥3 points) who underwent URSL were collected in this retrospective study between January 2015 and April 2021. The definition and scoring standards for preoperative high-risk factors associated with stones included whether the diameter of the stone was >2 cm, stone density was >1000 HU, there was a history of lithotripsy, the degree of hydronephrosis was greater than moderate, and there was an infection. Scores for stones were then assigned (yes = 1, no = 0), and the complicated stone case was defined as a total stone score ≥3 points. During the same period, PCNL was used in 171 patients with complicated impacted proximal ureteral calculi. Forty-five patients were selected as the control group and matched at a 1:1 ratio to index URSL cases regarding age, sex, and body mass index. Perioperative data were compared between the two groups. Results: All 90 operations were completed effectively. Compared to the URSL group, the surgical duration of the PCNL group was significantly shorter (53.69 ± 25.07 vs 73.46 ± 27.12 minutes, p < 0.05), stone-free rate (SFR) was significantly higher (93.3% vs 68.9%, p < 0.05), and total treatment cost was lower (US $1678.61 ± 714.86 vs US $3901.45 ± 1069.46, p < 0.05). Conversely, the URSL group had a shorter hospital stay (3.68 ± 2.70 vs 6.39 ± 3.34 days, p < 0.05). There was a significant difference in complication rate between the two groups regarding Clavien grade I, II, or III complications (20.0% in URSL group vs 8.9% in PCNL group, p = 0.037). Conclusion: PCNL had a better SFR and higher surgical efficacy, whereas URSL had a shorter perioperative period, but a lower initial SFR. PCNL is often more advantageous for complicated impacted proximal ureteral calculi.

Dark-Field Imaging Monitoring of Adenosine Triphosphate in Live Cells by Au NBPs@ZIF-8 Nanoprobes.

Monitoring the fluctuation of adenosine triphosphate (ATP) level in living cells could promote the understanding of metabolic pathways and cell biology. Here, we proposed a highly sensitive, selective, and biocompatible nanoprobe with core-shell structure, namely Au NBPs@ZIF-8 composed by gold nanobipyramids (Au NBPs) and zeolitic imidazolate framework-8 (ZIF-8), for monitoring intracellular ATP level fluctuation in living cells. Because the coordination between ATP and Zn2+ (the metal node of ZIF-8) was much stronger than that between 2-methylimidazole and Zn2+, which caused the decomposition of the ZIF-8 shell and the exposure of Au NBPs in the presence of ATP, it led to the change of the localized surface plasmon resonance scattering properties of nanoprobes under dark-field microscopy. Tricolor (RGB) analysis showed that R/G value had a good linear relationship with the ATP concentrations in the range of 10 µM to 4 mM (R2 = 0.999) with a detection limit of 5.28 µM. This ATP sensing platform also exhibited excellent selectivity in complex intracellular interfering substances. Besides, we realized intracellular ATP real-time imaging in HeLa cells and observed the ATP level fluctuation under dark-field microscopy. The method mentioned here could be further applied for delivery of therapeutics for biomedical applications.

Enhanced Peroxidase-like Activity of CuS Hollow Nanocages by Plasmon-Induced Hot Carriers and Photothermal Effect for the Dual-Mode Detection of Tannic Acid.

High catalytic activity is one of the necessary parameters for nanozymes to substitute for natural enzymes. It remains a great challenge to improve the specific enzyme-like activity of nanozymes as much as possible using the characteristics of nanomaterials for avoiding complexity and introducing additional uncertainties. Here, by combining the peroxidase (POD)-like activity and plasmon properties of CuS hollow nanocages (CuS HNCs), we demonstrate the feasibility of modulating the catalytic activity of nanozymes by the localized surface plasmon resonance (LSPR) effect. Rough surfaces and hollow-cage structures endow CuS HNCs with abundant hot spots to produce strong LSPR in the near-infrared (NIR) region, which makes the CuS HNCs simultaneously generate plentiful high-energy hot carriers and thermal effect to mediate H2O2 cleavage to yield the reactive oxide species (ROS) as well as speed up the reaction, leading to a dramatically enhanced POD-like activity. Based on the light-enhanced catalytic activity and high photothermal efficiency of the reaction system, a dual-mode strategy for detecting tannic acid (TA) is developed and successfully applied to determine the content of TA in different kinds of teas. This work not only provides a novel path for tuning the specific enzyme-like activity of nanomaterials but also shows a perspective for dual-mode sensing based on a photoinduced plasmon-enhanced effect.

Efficient and Sustainable in†situ Photo-Fenton Reaction to Remove Phenolic Pollutants by NH2 -MIL-101(Fe)/Ti3 C2 Tx Schottky-Heterojunctions.

Metal-organic frameworks (MOFs) with abundant active sites, a class of materials composed of metal nodes and organic ligands, is widely used for photocatalytic degradation of pollutants. However, the rapid recombination of photoinduced carriers of MOFs limits its photocatalytic degradation performance. Herein, Ti3 C2 Tx nanosheets-based NH2 -MIL-101(Fe) hybrids with Schottky-heterojunctions were fabricated by in situ hydrothermal assembly for improved photocatalytic activity. The photodegradation efficiencies of the NH2 -MIL-101(Fe)/Ti3 C2 Tx (N-M/T) hybrids for phenol and chlorophenol were 96.36 % and 99.83 % within 60 minutes, respectively. The N-M/T Schottky-heterojunction duly transferred electrons to the Ti3 C2 Tx nanosheets surface via built-in electric fields, effectively suppressing the recombination of photogenerated carriers, thereby improving the photocatalytic performance of NH2 -MIL-101(Fe). Moreover, the Fe-mixed-valence in the N-M/T led to improvement in the efficiency of the in situ generated photo-Fenton reactions, further enhancing the photocatalytic activity with more generated reactive oxygen species (ROS). The study proposes a highly effective removal of phenolic pollutants in wastewater.

Facile synthesis of binary two-dimensional lanthanide metal-organic framework nanosheets for ratiometric fluorescence detection of mercury ions.

Three boric acid-functionalized two-dimensional metal-organic frameworks (2D MOFs) nanosheets, namely, 2D Tb-bop, Eu-bop and Tb/Eu-bop nanosheets, were synthesized through simple mixing of a reaction mixture of Tb/Eu salts and 5-boronoisophthalic acid (5-bop) in the presence of triethylamine (TEA) at room temperature. The product had excellent mercury ions (Hg2+) sensing properties. The highly exposed boric acid sites on the surface of the 2D structure can undergo a transmetalation reaction with Hg2+ to promote the energy transfer between the ligand and the lanthanide ions, thus enhancing the emission of 2D Tb-bop and Eu-bop nanosheets and resulting in high sensitivity for Hg2+ sensing. Significantly, the Hg2+-induced transmetalation reaction in 2D binary Tb/Eu-bop nanosheets also enhanced the energy transfer between Tb3+ and Eu3+ nodes, showing a ratiometric fluorescence response toward Hg2+, and further improving the sensitivity. This novel 2D ratiometric fluorescence probe showed good linearity from 0.1 to 40 µM for Hg2+ with a detection limit of 4.83 nM. This work not only provided a simple and efficient strategy for synthesizing 2D MOFs but also yielded new insights for designing fluorescence probes with excellent sensing properties.

One-component nano-metal-organic frameworks with superior multienzyme-mimic activities for 1,4-dihydropyridine metabolism.

Although a number of nanozymes have been developed, it is still difficult to develop single-component nanozyme with overall high multienzyme-like activities. In this study, the nanosized metal-organic frameworks (nano-MOFs) FePCN (PCN stands for porous coordination network) was synthesized by integrating zirconium and iron ions with different catalytic property on single-component MOFs and exhibited superior intrinsic multienzyme-like activities, namely oxidase-, peroxidase- and phosphatase-mimicking activity. The catalytic active sites of oxidase- and peroxidase-, and phosphatase-like activity of FePCN were Fe-centers and Zr-O clusters, respectively. Based on the intrinsic oxidase-like activity and the similarity of molecular structures between cytochrome P450 oxidase (CYP) cofactors and the organic linker in FePCN, FePCN exhibited high CYP-like activity to catalyze the oxidation of hypotensive drug 1,4-dihydropyridine (1,4-DHP) into diethyl 2,6-dimethylpyridine-3,5-dicarboxylate (DDPD) and the yield of DDPD reached over 80%. Moreover, as peroxidase- and phosphatase-mimics, FePCN was successfully applied to detecting H2O2 under neutral condition and catalyzing the dephosphorylation of adenosine triphosphate (ATP), respectively. This study provides a feasible way for rational design one-component nanomaterials as multienzyme-mimics.

Advances in Endovascular Intervention Using Biomaterials: Study on Heat Efficiency of Scissor-Type Ultrasonic Catheter Device.

To improve the performance of the ultrasonic device during the endovascular operation, a scissor-type ultrasonic catheter device with compound vibration was developed. The heat generated by friction between the target and the device affects its coagulation mechanism while the actuator contacts the tissue. The scissor-type ultrasonic catheter device proposed in this study is expected to improve heat generation performance because it has the action of rubbing the object when it is pushed by combined vibration. In addition, since it is constructed by simple notch processing, it can be miniaturized and can be expected to be introduced into catheters. However, the observation of ultrasonic vibration during frictional heating is difficult, which is an issue for device design. In this paper, a thermal-structure coupling analysis was done using the finite element method to calculate the heat generation efficiency and evaluate its coagulation performance.

Lattice expansion and oxygen vacancy of α-Fe2O3 during gas sensing.

Identifying the nature of gas-sensing material under the real-time operating condition is very critical for the research and development of gas sensors. In this work, we implement in situ Raman and XRD to investigate the gas-sensing nature of α-Fe2O3 sensing material, which derived from Fe-based metal-organic gel (MOG). The active mode of α-Fe2O3 as gas-sensing material originate from the thermally induced lattice expansion and the changes of surface oxygen vacancy of α-Fe2O3 could be reflected from the further monitored Raman scattering signals during acetone gas sensing. Meanwhile, the prepared α-Fe2O3 gas sensor exhibits excellent gas-sensing performance with high response value (Ra/Rg = 27), rapid response/recovery time (1 s/80 s) for 100 ppm acetone gas, and broad response range (5 - 900 ppm) at 183 °C. Strategies described herein could provide a promising approach to obtain gas-sensing materials with excellent performance and unveil the gas-sensing nature for other metal-oxide-based chemiresistors.

Metal-Organic Gel-Derived Multimetal Oxides as Effective Electrocatalysts for the Oxygen Evolution Reaction.

Exploring efficient and durable catalysts derived from earth-abundant and cost-effective materials is a highly desirable route to overcome the sluggish anodic oxygen evolution reaction (OER). A series of multinary metal-organic gels (MOGs) with various and alterable metal element compositions are prepared by straightforward mixing of metal ions with ligand 4,4',4''-[(1,3,5-triazine-2,4,6-triyl)tris(azanediyl)]tribenzoic acid (H3 TATAB) in solution at room temperature. Spinel-type metal oxides with excellent electrocatalytic OER performance were then obtained through calcination of the as-synthesized MOGs. In electrochemical testing, the trimetallic oxide CoFeNi-O-1 (derived from the MOG with a Co/Fe/Ni molar ratio of 5:1:4) exhibits remarkable catalytic activity with a low overpotential of 244 mV at a current density of 10 mA cm-2 and a small Tafel slope of 55.4 mV dec-1 in alkaline electrolyte, outperforming most recently reported electrocatalysts. This work not only provides a promising OER catalyst and enriches the application of MOGs in the catalytic field, but also offers a facile new route to acquiring multicomponent metal oxides with high electrocatalytic activity.

Integrated System for Monitoring Muscular States during Elbow Flexor Resistance Training in Bedridden Patients.

To improve or maintain the physical function of bedridden patients, appropriate and effective exercises are required during the patient's bed rest. Resistance training (RT) is an effective exercise for improving the physical function of bedridden patients, and the improvement of the physical function is caused by mechanical stimuli associated with RT. Currently, the measured mechanical stimuli are external variables which represent the synthetic effect of multiple muscles and body movements. Important features of stimuli experienced by muscles are of crucial importance in explaining muscular strength and power adaptation. This study describes an integrated system for assessing muscular states during elbow flexor resistance training in bedridden patients, and some experiments were carried out to test and evaluate this system. The integrated system incorporates an elbow joint angle estimation model (EJAEM), a musculoskeletal model (MSM), and a muscle-tendon model. The EJAEM enables real-time interaction between patient and MSM. The MSM is a three-dimensional model of the upper extremity, including major muscles that make up the elbow flexor and extensor, and was built based on public data. One set of concentric and eccentric contraction was performed by a healthy subject, and the results of the calculations were analyzed to show important features of mechanical stimuli experienced by muscles during the training. The integrated system provides a considerable method to monitor the body-level and muscle-level mechanical stimuli during elbow flexor resistance training in bedridden patients.

Enabling user mobility for optical camera communication using mobile phone.

We propose and experimentally demonstrate an optical camera communication (OCC) supporting user mobility. A mobile test platform is designed to emulate user mobility. In the mobile scenario, dynamic column matrix selection algorithm is proposed to select an appropriate column matrix with high extinction-ratio (ER) while avoiding the blooming effect. The mobile phone is placed on the moving track to receive the visible light at a vertical distance of 60 cm. By varying the moving speed at 20, 40, 60, 80, and 100 cm/s and lateral distance at 50 and 70 cm respectively, the system performance using the proposed algorithm is investigated. The experimental results show that with the increase of lateral distance (far from the light source) and user moving speed, the system performance gets degraded. Moreover, it demonstrates that the mobile system can achieve a throughput of 4.08 kbps under a low illuminance of 275 lx.

Genome-Wide Screening for Novel Candidate Virulence Related Response Regulator Genes in Xanthomonas oryzae pv. oryzicola.

Two-component regulatory system (TCS), a major type of cellular signal transduction system, is widely used by bacteria to adapt to different conditions and to colonize certain ecological niches in response to environmental stimuli. TCSs are of distinct functional diversity, genetic diversity, and species specificity (pathovar specificity, even strain specificity) across bacterial groups. Although TCSs have been demonstrated to be crucial to the virulence of Xanthomonas, only a few researches have been reported about the studies of TCSs in Xanthomonas oryzae pathovar oryzicola (hereafter Xoc), the pathogen of rice bacterial streak disease. In the genome of Xoc strain GX01, it has been annotated 110 TCSs genes encoding 54 response regulators (RRs), 36 orthodox histidine kinase (HKs) and 20 hybrid histidine kinase (HyHKs). To evaluate the involvement of TCSs in the stress adaptation and virulence of Xoc, we mutated 50 annotated RR genes in Xoc GX01 by homologous vector integration mutagenesis and assessed their phenotypes in given conditions and tested their virulence on host rice. 17 RR genes were identified to be likely involved in virulence of Xoc, of which 10 RR genes are novel virulence genes in Xanthomonas, including three novel virulence genes for bacteria. Of the novel candidate virulence genes, some of which may be involved in the general stress adaptation, exopolysaccharide production, extracellular protease secretion and swarming motility of Xoc. Our results will facilitate further studies on revealing the biological functions of TCS genes in this phytopathogenic bacterium.

A Novel Sleep Respiratory Rate Detection Method for Obstructive Sleep Apnea Based on Characteristic Moment Waveform.

Obstructive sleep apnea (OSA) affecting human's health is a kind of major breathing-related sleep disorders and sometimes leads to nocturnal death. Respiratory rate (RR) of a sleep breathing sound signal is an important human vital sign for OSA monitoring during whole-night sleeping. A novel sleep respiratory rate detection with high computational speed based on characteristic moment waveform (CMW) method is proposed in this paper. A portable and wearable sound device is used to acquire the breathing sound signal. And the amplitude contrast decreasing has been done first. Then, the CMW is extracted with suitable time scale parameters, and the sleep RR value is calculated by the extreme points of CMW. Experiments of one OSA case and five healthy cases are tested to validate the efficiency of the proposed sleep RR detection method. According to manual counting, sleep RR can be detected accurately by the proposed method. In addition, the apnea sections can be detected by the sleep RR values with a given threshold, and the time duration of the segmentation of the breath can be calculated for detailed evaluation of the state of OSA. The proposed method is meaningful for continued research on the sleep breathing sound signal.

Simple preparation of magnetic metal-organic frameworks composite as a "bait" for phosphoproteome research.

Phosphospecific enrichment techniques and mass spectrometry (MS) are primary tools for comprehending the cellular phosphoproteome. In this work, a rational and extremely facile route to synthesize the magnetic metal-organic frameworks (mMOFs) was employed and the prepared composite was first utilized as a "bait" for selective enrichment of phosphopeptides. Typically, the mMOFs was synthesized via electrostatic self-assembly between the negatively charged Fe3O4 magnetic nanoparticles (MNPs) and positively charged MIL-101(Fe). The obtained Fe3O4/MIL-101(Fe) composite possessed well-defined structures, rough surface, highly specific surface area and excellent magnetic property. To demonstrate their ability for enrichment of phosphopeptides, we applied Fe3O4/MIL-101(Fe) as a "bait" to capture the phosphopeptides from standard protein digestion and practical samples. The enriched phosphopeptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The MS results show that the Fe3O4/MIL-101(Fe) exhibits superior enrichment performance for phosphopeptides with low detectable concentration assessed to be 8 fmol, selectivity investigated to be 1:1000 using ß-casein/bovine serum albumin mixture and enrichment recovery evaluated to be 89.8%. Based on these excellent properties, the prepared composite was used to enrich the phosphopeptides from tilapia eggs biological samples for the first time. A total number of 51 phosphorylation sites were identified from the digest of tilapia eggs proteins, suggesting the excellent potential of Fe3O4/MIL-101(Fe) composite in the practical application.

MIL-101(Cr) as matrix for sensitive detection of quercetin by matrix-assisted laser desorption/ionization mass spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has been proven as a useful and advanced technique in the identification of polymers and proteins. However, MALDI-TOF-MS still has the unavoidable drawback of self-signal interference with traditional organic matrices, which could suppress and overlap with the analyte signals in the low-mass region. In this work, MIL-101(Cr), a kind of metal-organic frameworks which possess high molecular weight, π-conjugated 3-D structure, coordinately unsaturated chromium sites (CUS) and strong absorption in the UV range, was employed to replace traditional organic matrices, and it was found that MIL-101(Cr) can dramatically eliminate the background peaks, showing high signal-to-noise level in the analysis of small molecules. As proof-of-concept, quercetin, daidzein, genistein and naringenin, members of flavonol family which widely exists in food and natural products, were successfully determined by utilizing MIL-101(Cr) as the surface-assisted matrix, and the detection of quercetin was sensitive with good salt tolerance and reproducibility. Under optimal conditions, the mass peak intensity exhibited good linear relationships in the range from 0.25µg/mL-7.00µg/mL for quercetin (R2=0.996) with detection limit 2.11ng/mL (3σ/k), making the identification of quercetin in sophora japonica successfully. With this strategy we have demonstrated the potentiality of MIL-101(Cr) nanomaterials as MALDI-MS matrix for the detection of small molecules.