Oxophilic Ce single atoms-triggered active sites reverse for superior alkaline hydrogen evolution.

The state-of-the-art alkaline hydrogen evolution catalyst of united ruthenium single atoms and small ruthenium nanoparticles has sparked considerable research interest. However, it remains a serious problem that hydrogen evolution primarily proceeds on the less active ruthenium single atoms instead of the more efficient small ruthenium nanoparticles in the catalyst, hence largely falling short of its full activity potential. Here, we report that by combining highly oxophilic cerium single atoms and fully-exposed ruthenium nanoclusters on a nitrogen functionalized carbon support, the alkaline hydrogen evolution centers are facilely reversed to the more active ruthenium nanoclusters driven by the strong oxophilicity of cerium, which significantly improves the hydrogen evolution activity of the catalyst with its mass activity up to -10.1 A mg-1 at -0.05 V. This finding is expected to shed new light on developing more efficient alkaline hydrogen evolution catalyst by rational regulation of the active centers for hydrogen evolution.

Recent development of piezoelectric biosensors for physiological signal detection and machine learning assisted cardiovascular disease diagnosis.

As cardiovascular disease stands as a global primary cause of mortality, there has been an urgent need for continuous and real-time heart monitoring to effectively identify irregular heart rhythms and to offer timely patient alerts. However, conventional cardiac monitoring systems encounter challenges due to inflexible interfaces and discomfort during prolonged monitoring. In this review article, we address these issues by emphasizing the recent development of the flexible, wearable, and comfortable piezoelectric passive sensor assisted by machine learning technology for diagnosis. This innovative device not only harmonizes with the dynamic mechanical properties of human skin but also facilitates continuous and real-time collection of physiological signals. Addressing identified challenges and constraints, this review provides insights into recent advances in piezoelectric cardiac sensors, from devices to circuit systems. Furthermore, this review delves into the integration of machine learning technologies, showcasing their pivotal role in facilitating continuous and real-time assessment of cardiac status. The synergistic combination of flexible piezoelectric sensor design and machine learning holds substantial potential in automating the detection of cardiac irregularities with minimal human intervention. This transformative approach has the power to revolutionize patient care paradigms.

2D Material and Perovskite Heterostructure for Optoelectronic Applications.

Optoelectronic devices are key building blocks for sustainable energy, imaging applications, and optical communications in modern society. Two-dimensional materials and perovskites have been considered promising candidates in this research area due to their fascinating material properties. Despite the significant progress achieved in the past decades, challenges still remain to further improve the performance of devices based on 2D materials or perovskites and to solve stability issues for their reliability. Recently, a novel concept of 2D material/perovskite heterostructure has demonstrated remarkable achievements by taking advantage of both materials. The diverse fabrication techniques and large families of 2D materials and perovskites open up great opportunities for structure modification, interface engineering, and composition tuning in state-of-the-art optoelectronics. In this review, we present comprehensive information on the synthesis methods, material properties of 2D materials and perovskites, and the research progress of optoelectronic devices, particularly solar cells and photodetectors which are based on 2D materials, perovskites, and 2D material/perovskite heterostructures with future perspectives.

Functional analysis of the SlERF01 gene in disease resistance to S. lycopersici.

BACKGROUND: Tomato gray leaf spot caused by Stemphylium lycopersici (S. lycopersici) is a serious disease that can severely hinder tomato production. To date, only Sm has been reported to provide resistance against this disease, and the molecular mechanism underlying resistance to this disease in tomato remains unclear. To better understand the mechanism of tomato resistance to S. lycopersici, real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR)-based analysis, physiological indexes, microscopy observations and transgenic technology were used in this study. RESULTS: Our results showed that the expression of SlERF01 was strongly induced by S. lycopersici and by exogenous applications of the hormones salicylic acid (SA) and jasmonic acid (JA). Furthermore, overexpression of SlERF01 enhanced the hypersensitive response (HR) to S. lycopersici and elevated the expression of defense genes in tomato. Furthermore, the accumulation of lignin, callose and hydrogen peroxide (H2O2) increased in the transgenic lines after inoculation with S. lycopersici. Taken together, our results showed that SlERF01 played an indispensable role in multiple SA, JA and reactive oxygen species (ROS) signaling pathways to provide resistance to S. lycopersici invasion. Our findings also indicated that SlERF01 could activate the expression of the PR1 gene and enhance resistance to S. lycopersici. CONCLUSIONS: We identified the SlERF01 gene, which encodes a novel tomato AP2/ERF transcription factor (TF). Functional analysis revealed that SlERF01 positively regulates tomato resistance to S. lycopersici. Our findings indicate that SlERF01 plays a key role in multiple SA, JA and ROS signaling pathways to provide resistance to invasion by S. lycopersici. The findings of this study not only help to better understand the mechanisms of response to pathogens but also enable targeted breeding strategies for tomato resistance to S. lycopersici.

Lung Nodule Detection in CT Images Using a Raw Patch-Based Convolutional Neural Network.

Remarkable progress has been made in image classification and segmentation, due to the recent study of deep convolutional neural networks (CNNs). To solve the similar problem of diagnostic lung nodule detection in low-dose computed tomography (CT) scans, we propose a new Computer-Aided Detection (CAD) system using CNNs and CT image segmentation techniques. Unlike former studies focusing on the classification of malignant nodule types or relying on prior image processing, in this work, we put raw CT image patches directly in CNNs to reduce the complexity of the system. Specifically, we split each CT image into several patches, which are divided into 6 types consisting of 3 nodule types and 3 non-nodule types. We compare the performance of ResNet with different CNNs architectures on CT images from a publicly available dataset named the Lung Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI). Results show that our best model reaches a high detection sensitivity of 92.8% with 8 false positives per scan (FPs/scan). Compared with related work, our work obtains a state-of-the-art effect.

Fluorescent methionine-capped gold nanoclusters for ultra-sensitive determination of copper(II) and cobalt(II), and their use in a test strip.

A fluorometric assay was constructed for supersensitive determination of Cu2+ and Co2+ based on their quenching effect on the orange fluorescence of methionine-capped gold nanoclusters (Met-AuNCs). A simple one-step method was developed for the preparation of the Met-AuNCs, employing L-methionine as both a reducing and protecting reagent. Within 10 min, water soluble Met-AuNCs were obtained with an average size of 2.4 nm. Under photoexcitation at 370 nm, the Met-AuNCs possess a maximum emission at 580 nm and a quantum yield of 2.3%. The response is fast (1 min), and the selectivity for Cu2+ and Co2+ is high over other metal ions. The detection limits for Cu2+ and Co2+ are around 47 and 420 pM, respectively. The effects were used to design a test paper for visual detection of Cu2+ and Co2+. Using this test paper, 1 µM of Cu2+/Co2+ can be detect under the UV lamp (365 nm excitation). It is perceived to be a promising tool for the rapid on-site determination of Cu2+ and Co2+ in real water samples. Graphical abstract Schematic presentation of gold nanoclusters (AuNCs) synthesis with methionine as both reducing and protecting reagent, Cu2+/Co2+ detection based on the quenching of the fluorescence of AuNCs, and visual detection of Cu2+/Co2+ based on a respective test strip.

Repair of the musculocutaneous nerve using the vagus nerve as donor by helicoid end-to-side technique: an experimental study in rats.

Although several donor nerves can be chosen to repair avulsed brachial plexus nerve injury, available nerves are still limited. The purpose of this study is to validate whether the vagus nerve (VN) can be used as a donor. Eighteen Sprague-Dawley male rats were divided into three groups (n = 6). The right musculocutaneous nerve (McN) was transected with differing subsequent repair. (1) HS-VN group: a saphenous nerve (SN) graft-end was helicoidally wrapped round the VN side (epi-and perineurium was opened) with a 30 ° angle, distal SN end was coapted to the McN with end-to-end repair. (2) EE-PN group: a SN was interpositionally grafted between the transected phrenic nerve (PN) and the McN by end-to-end coaptation. (3) Sham control group: McN was transected and not repaired and postoperative vital signs were checked daily. At three months, electrophysiology, tetanic force, wet biceps muscle weight, and histology were evaluated. Every tested mean value in HS-VN group was significantly greater than the EE-PN or the sham control groups (p < 0.05 or p < 0.005). The mean recovery ratio of regenerated nerve fibers was 96% and, in HS-VN group, the mean recovery ratio of CMAP was 79%. No vital signs changed in any group. There was no statistical difference (p > 0.5) between the mean VN nerve-fiber numbers of the segments proximal (2237 ± 134) and distal (2150 ± 156) to the VN graft-attachment site. Histological analysis revealed no axon injury or intraneural scarring at any point along the VN. This study demonstrated that VN is a practical and reliable donor nerve for end-to-side nerve transfer. © 2017 Wiley Periodicals, Inc.

Best time window for the use of calcium-modulating agents to improve functional recovery in injured peripheral nerves-An experiment in rats.

Peripheral nerve injury can have a devastating effect on daily life. Calcium concentrations in nerve fibers drastically increase after nerve injury, and this activates downstream processes leading to neuron death. Our previous studies showed that calcium-modulating agents decrease calcium accumulation, which aids in regeneration of injured peripheral nerves; however, the optimal therapeutic window for this application has not yet been identified. In this study, we show that calcium clearance after nerve injury is positively correlated with functional recovery in rats suffering from a crushed sciatic nerve injury. After the nerve injury, calcium accumulation increased. Peak volume is from 2 to 8 weeks post injury; calcium accumulation then gradually decreased over the following 24-week period. The compound muscle action potential (CMAP) measurement from the extensor digitorum longus muscle recovered to nearly normal levels in 24 weeks. Simultaneously, real-time polymerase chain reaction results showed that upregulation of calcium-ATPase (a membrane protein that transports calcium out of nerve fibers) mRNA peaked at 12 weeks. These results suggest that without intervention, the peak in calcium-ATPase mRNA expression in the injured nerve occurs after the peak in calcium accumulation, and CMAP recovery continues beyond 24 weeks. Immediately using calcium-modulating agents after crushed nerve injury improved functional recovery. These studies suggest that a crucial time frame in which to initiate effective clinical approaches to accelerate calcium clearance and nerve regeneration would be prior to 2 weeks post injury. © 2017 Wiley Periodicals, Inc.

Effect of calcitonin on cultured schwann cells.

INTRODUCTION: After nerve injury, calcium concentrations in intranerve fibers quickly increase. We have shown that functional recovery of injured nerves correlates with calcium absorption. A slight increase in calcium reduces the number of Schwann cells present. Calcitonin therapy greatly improves regeneration by accelerating calcium absorption. We examined the effect of adding calcitonin to higher concentration calcium media on cultured Schwann cells. METHODS: The cells, isolated from intact sciatic nerves, were cultured with normal or higher concentration calcium media with or without calcitonin. Schwann cells were incubated with anti-S-100, goat-anti-mouse, and propidium iodide and then viewed through fluorescent light and phase-contrast microscopy for observation and analysis. RESULTS: The cells in each calcitonin-containing medium showed many Schwann cells, however, the cells in the higher concentration calcium media showed fewer and more defective Schwann cells. CONCLUSION: These results show that calcitonin protects against the harmful effects of excessive calcium encountered in peripheral nerve injury. Muscle Nerve 56: 768-772, 2017.