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Organic electrochemical transistors (OECTs) possess low operating voltage and excellent amplification capability and show promising applications in biosensors and flexible electronics. However, the active layers of OECTs are usually dense films, which show limited ion penetration/transport, resulting in limited performances of OECTs. Here, unprecedented high‐performance flexible multifunctional OECTs based on nanoporous (mainly 2–60 nm), high‐specific‐surface‐area (255–281 m2 g−1), and flexible conjugated polymer aerogel films are developed. The nanoporous structures effectively facilitate ion penetration/transport, leading to significantly enhanced transconductance (48.5–53.5 mS) and on/off ratio (6.4 × 104) of the OECTs compared with those of dense devices. The resulting OECT‐based glucose sensors exhibit an ultralow detection limit of 1 pm, approximately two to three orders of magnitude lower than those of the previously reported OECT glucose sensors, and an ultrabroad detection range of 1 pm–5 m. They can detect trace amounts of glucose in sweat, serum, saliva, and urine in real time. Moreover, the OECTs can be used for high‐performance flexible artificial synapses and electrocardiogram monitoring. This work provides a powerful strategy toward highly sensitive biosensors, artificial synapses, and electrophysiological signal monitoring. [ABSTRACT FROM AUTHOR]

Simple Summary: In this experiment, porcine embryos were used as research subjects, and the effects of caffeic acid phenethyl ester on the embryos' quality and the mitochondrial function were evaluated by examining the quality and developmental ability of blastocysts, the antioxidant properties of embryos, and the mitochondrial function, endoplasmic reticulum stress level, autophagy, and apoptosis. Caffeic acid phenethyl ester (CAPE) is one of the main active components of the natural medicine propolis, which has antioxidant, anti-tumor, and immunomodulatory activities. This study aimed to analyze the effects and underlying mechanisms of CAPE added to the medium of in vitro cultures on the developmental competence, mitochondria, and endoplasmic reticulum of porcine embryos. The results demonstrated that 1 nM of CAPE significantly improved the quality of porcine embryos, increased the rate of blastocyst formation, and enhanced the proliferation ability. It also enhanced mitochondrial function by increasing the level of mitochondrial membrane potential and expression of the mitochondrial biogenesis-related protein PPARgamma coactivator 1 alpha and beta (PGC1 alpha and beta), regulating mitochondrial biogenesis, and increasing adenosine triphosphate (ATP) content. In addition, CAPE alleviated oxidative and endoplasmic reticulum (ER) stress in embryos by decreasing ROS accumulation and increasing glutathione content, as well as elevating Nrf2 and reducing GRP78 (ER stress marker) expression levels. Moreover, CAPE reduced the levels of apoptosis and autophagy in the cultivated embryos. These results indicate that CAPE improves the quality and enhances the mitochondrial function of in vitro-produced porcine embryos by alleviating oxidative and ER stress. [ABSTRACT FROM AUTHOR]

As an important instrument for olfactory detection in non-destructive testing (NDT), the electronic nose plays an important role in simulating olfactory detection. However, its performance is often affected by drift phenomena, including changes in sensor performance caused by environmental factors and olfactory fatigue due to long-term use. Although the effect of drift on the performance of electronic noses is widely recognized, there is still a relative lack of research on how drift affects feature optimization. This study presents a novel idea that drift factors not only affect the direct readings of the sensor but may also have a profound effect on the feature optimization process and hence the compensation of the electronic nose. To explore this concept, we chose temperature and humidity, the two most common environmental drift factors, for our experimental study. In our study, we verified the impact of drift factors on feature optimization and found a positive correlation between the concentration of sensor scores and the correct classification rate. Moreover, we adopted an innovative quadratic feature optimization method, which aims to reduce the influence of the drift factor on the feature optimization process and thus improve the drift resistance of the electronic nose. In our experiments, we found that the unweighted quadratic feature optimization method performs best in reducing the drift effect. After the optimization process, the recognition rate reaches 100% in the training set and 96% in the test set, which indicates that the electronic nose has improved significantly in terms of drift resistance. In summary, this study explores the effect of drift factors on feature optimization and proposes an effective treatment method, which provides a reference direction for the development and optimization of electronic nose technology. [ABSTRACT FROM AUTHOR]

With the increasing demands for artificial intelligence, robotics, electronic skin, healthcare, and energy storage/conversion, the research focus on flexible electronics has started to shift from being merely bendable and rollable to being stretchable. In recent years, stretchable aerogels and foams have drawn significant attention in the field of flexible electronics due to their unique porous structures, low density, high porosity, and high flexibility. This work provides a comprehensive review of the state‐of‐the‐art developments in stretchable aerogels and foams, encompassing their preparation, structures, properties, and applications. The preparation methods, typical structures of stretchable aerogels and foams, stretching principle, and the relationship between their structures, stretchability, and other properties are investigated. Their latest applications in stretchable strain/pressure sensors, electrodes and conductors, chemical sensors and biosensors, supercapacitors, batteries, triboelectric nanogenerators, electromagnetic shielding, microwave absorption, thermal management, adsorption, separation/filtration, and shape memory are introduced. Furthermore, the challenges and opportunities of stretchable aerogels and foams are summarized. This work provides a guideline for the development of stretchable aerogels and foams and next‐generation high‐performance flexible electronics based on stretchable porous materials. [ABSTRACT FROM AUTHOR]

Enhancing the efficiency of charge carrier separation is crucial for improving the performance of photocatalysts, thereby offering more effective solutions to energy and environmental pollution challenges. In this study, a carbon‐deficient ultra‐thin porous g‐C3N4 (Vc‐UPCN) was synthesized and subsequently was integrated with Bi2Fe4O9 (BFO) using a sonochemical self‐assembly technique, a Bi2Fe4O9/Vc‐UPCN (BC) photocatalyst featuring a Z‐scheme heterojunction. The BC catalyst was subjected to corona poling treatment to obtain BCp, which possesses an intrinsic electric field. Compared with pure BFO and Vc‐UPCN, the BC heterojunction exhibited higher photo‐generated electron–hole separation efficiency and photodegradation ability. Upon introduction of corona polarization, the photocatalytic performance of BC was further enhanced. Specifically, BCp‐15 (BFO/BC mass fraction = 15) achieved complete degradation of methylene blue (MB) within 30 min. BCp‐15 demonstrated that its degradation efficiency for MB was 1.28 times higher than that of BC‐15, 1.85 times higher than that of Vc‐UPCN, and impressive 7.69 times higher than that of pure BFO. The coupling effect of the heterojunction and ferroelectric polarization significantly improved the separation efficiency of photo‐generated carriers in BCp. This study is expected to provide a reference for the synergistic application of heterojunction and ferroelectric polarization in traditional semiconductor photocatalysis. [ABSTRACT FROM AUTHOR]

In-depth understanding of the layer-by-layer process is critical for the quality control of additive manufactured (AM) components. Besides the development of experimental techniques, computational modelling is another important way to study the AM mechanisms in detail. However, currently there is still lack of a modelling platform that integrates all the necessary physics involved in the AM process. In the present study, we develop a modelling framework that integrates a phase field method for microstructure evolution, a lattice Boltzmann method for melt pool dynamics, a modified ray-tracing method for laser-material interaction, and a minimum gravity energy algorithm for powder bed generation to simulate the single-track, powder bed fusion (PBF) process of NiTi shape memory alloy. Our simulation shows that different from keyhole depth, melt pool size does not obey the scaling law with line energy density, the keyhole depth and the overlapping ratio of laser spot vs. keyhole opening together determine the laser absorptivity. Based on the simulation finding, we also develop a self-consistent analytical model to predict the keyhole depth and the absorptivity for given scanning parameters. The present work lays a solid foundation towards quantitative understanding of multi-layer AM process.

ABSTRACT The banning of colistin as a feed additive for food-producing animals in mainland China in 2017 caused the decline in the prevalence of Escherichia coli-mobilized colistin resistance (mcr-1) in China. Salmonella Typhimurium and its monophasic 1,4,[5],12:i:- variants are also the main species associated with the spread of mcr-1; however, the evidence of the prevalence and transmission of mcr-1 among Salmonella is lacking. Herein, the 5,354 Salmonella isolates recovered from fecal samples of diarrheal patients in Guangdong, Southern China, from 2009 to 2019 were screened for colistin resistance and mcr-1, and mcr-1-positive isolates were characterized based on whole-genome sequencing (WGS) data. Relatively high prevalence rates of colistin resistance and mcr-1 (4.05%/4.50%) were identified, and more importantly, the prevalence trends of colistin-resistant and mcr-1-positive Salmonella isolates had a similar dynamic profile, i.e., both were first detected in 2012 and rapidly increased during 2013 to 2016, followed by a sharp decrease since 2017. WGS and phylogenetic analysis indicate that, whether before or after the ban, the persistence and cross-hospital transmission of mcr-1 are primarily determined by IncHI2 plasmids with similar backbones and sequence type 34 (ST34) Salmonella in specific clades that are associated with a high prevalence of IncHI2 plasmids and clinically important antimicrobial resistance genes, including blaCTX-M-14-fosA3-oqxAB-floR genotypes. Our work reveals the difference in the prevalence rate of mcr-1 in clinical Salmonella before and after the Chinese colistin ban, whereas mcr-1 transmission was closely linked to multidrug-resistant IncHI2 plasmid and ST34 Salmonella across diverse hospitals over 10 years. Continued surveillance is required to explore the factors related to a sharp decrease in mcr-1 after the recent ban and determine whether the ban has affected the carriage of mcr-1 in Salmonella circulating in the health care system. IMPORTANCE Colistin is one of the last-line antibiotics for the clinical treatment of Enterobacteriaceae. However, the emergence of the mobilized colistin resistance (mcr-1) gene has spread throughout the entire human health system and largely threatens the usage of colistin in the clinical setting. In this study, we investigated the existence of mcr-1 in clinical Salmonella from a 10-year continuous surveillance and genomic study. Overall, the colistin resistance rate and mcr-1 carriage of Salmonella in tertiary hospitals in Guangdong (2009 to 2019) were relatively high and, importantly, rapidly increased from 2013 to 2016 and significantly decreased after the Chinese colistin withdrawal. However, before or after the ban, the MDR IncHI2 plasmid with a similar backbone and ST34 Salmonella were the main vectors involved in the spread of mcr-1. Interestingly, these Chinese mcr-1-carrying Salmonella obtain phylogenetically and phylogeographically distinct patterns compared with those from other continents and are frequently associated with clinically important ARGs including the extended-spectrum β-lactamases. Our data confirmed that the national stewardship intervention seems to be successful in blocking antibiotic resistance determinants and that continued surveillance of colistin resistance in clinical settings, farm animals, and related products is necessary.

Synaptic vesicle and active zone proteins are required for synaptogenesis. The molecular mechanisms for coordinated synthesis of these proteins are not understood. Using forward genetic screens, we identified the conserved THO nuclear export complex (THOC) as an important regulator of presynapse development in C. elegans dopaminergic neurons. In THOC mutants, synaptic messenger RNAs are retained in the nucleus, resulting in dramatic decrease of synaptic protein expression, near complete loss of synapses, and compromised dopamine function. CRE binding protein (CREB) interacts with THOC to mark synaptic transcripts for efficient nuclear export. Deletion of Thoc5, a THOC subunit, in mouse dopaminergic neurons causes severe defects in synapse maintenance and subsequent neuronal death in the substantia nigra compacta. These cellular defects lead to abrogated dopamine release, ataxia, and animal death. Together, our results argue that nuclear export mechanisms can select specific mRNAs and be a rate-limiting step for neuronal differentiation and survival.

Proper morphogenesis of dendrites plays a fundamental role in the establishment of neural circuits. The molecular mechanism by which dendrites grow highly complex branches is not well understood. Here, using the Caenorhabditis elegans PVD neuron, we demonstrate that high-order dendritic branching requires actin polymerization driven by coordinated interactions between two membrane proteins, DMA-1 and HPO-30, with their cytoplasmic interactors, the RacGEF TIAM-1 and the actin nucleation promotion factor WAVE regulatory complex (WRC). The dendrite branching receptor DMA-1 directly binds to the PDZ domain of TIAM-1, while the claudin-like protein HPO-30 directly interacts with the WRC. On dendrites, DMA-1 and HPO-30 form a receptor-associated signaling complex to bring TIAM-1 and the WRC to close proximity, leading to elevated assembly of F-actin needed to drive high-order dendrite branching. The synergistic activation of F-actin assembly by scaffolding distinct actin regulators might represent a general mechanism in promoting complex dendrite arborization.

Abstract Background Ferroptosis is a recently recognised new type of cell death which may be a potential target for cancer therapy. In the present study, we aimed to screen ferroptosis-related differentially expressed long non-coding RNAs as biomarkers to predict the outcome of kidney renal clear cell carcinoma. Methods RNAseq count data and corresponding clinical information were obtained from the Cancer Genome Atlas database. Lists of ferroptosis-related genes and long non-coding RNAs were obtained from the FerrDb and GENCODE databases, respectively. The candidate prognostic signatures were screened by Cox regression analyses and least absolute shrinkage and selection operator analyses. Results Three ferroptosis-related long non-coding RNAs (DUXAP8, LINC02609, and LUCAT1) were significantly correlated with the overall survival of kidney renal clear cell carcinoma independently. Kidney renal clear cell carcinoma patients with high-risk values displayed worse OS. Meanwhile, the expression of these three ferroptosis-related long non-coding RNAs and their risk scores were significantly correlated with clinicopathological features. Principal component analyses showed that patients with kidney renal clear cell carcinoma have differential risk values were well distinguished by the three ferroptosis-related long non-coding RNAs. Conclusions The present study suggests that the risk assessment model constructed by these three ferroptosis-related long non-coding RNAs could accurately predict the outcome of kidney renal clear cell carcinoma. We also provide a novel perspective for cancer prognosis screening.