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During plant-pathogen interactions, plants use intracellular proteins with nucleotide-binding site and Leu-rich repeat (NBS-LRR) domains to detect pathogens. NBS-LRR proteins represent a major class of plant disease resistance genes (R-genes). Whereas R-genes have been well characterized in angiosperms, little is known about their origin and early diversification. Here, we perform comprehensive evolutionary analyses of R-genes in plants and report the identification of R-genes in basal-branching streptophytes, including charophytes, liverworts, and mosses. Phylogenetic analyses suggest that plant R-genes originated in charophytes and R-proteins diversified into TIR-NBS-LRR proteins and non-TIR-NBS-LRR proteins in charophytes. Moreover, we show that plant R-proteins evolved in a modular fashion through frequent gain or loss of protein domains. Most of the R-genes in basal-branching streptophytes underwent adaptive evolution, indicating an ancient involvement of R-genes in plant-pathogen interactions. Our findings provide novel insights into the origin and evolution of R-genes and the mechanisms underlying colonization of terrestrial environments by plants.

The deep history and early diversification of retroviruses remains elusive, largely because few retroviruses have been characterized in vertebrates other than mammals and birds. Endogenous retroviruses (ERVs) documented past retroviral infections and thus provide 'molecular fossils' for studying the deep history of retroviruses. Here we perform a comprehensive phylogenomic analysis of ERVs within the genomes of 92 non-avian/mammalian vertebrates, including 72 fishes, 4 amphibians, and 16 reptiles. We find that ERVs are present in all the genomes of jawed vertebrates, revealing the ubiquitous presence of ERVs in jawed vertebrates. We identify a total of >8,000 ERVs and reconstruct ~450 complete or partial ERV genomes, which dramatically expands the phylogenetic diversity of retroviruses and suggests that the diversity of exogenous retroviruses might be much underestimated in non-avian/mammalian vertebrates. Phylogenetic analyses show that retroviruses cluster into five major groups with different host distributions, providing important insights into the classification and diversification of retroviruses. Moreover, we find retroviruses mainly underwent frequent host switches in non-avian/mammalian vertebrates, with exception of spumavirus-related viruses that codiverged with their ray-finned fish hosts. Interestingly, ray-finned fishes and turtles appear to serve as unappreciated hubs for the transmission of retroviruses. Finally, we find retroviruses underwent many independent water-land transmissions, indicating the water-land interface is not a strict barrier for retrovirus transmission. Our analyses provide unprecedented insights into and valuable resources for studying the diversification, key evolutionary transitions, and macroevolution of retroviruses.

In the context of increasing resource scarcity and environmental concerns, the development of green composite materials is essential for promoting sustainability in the automotive industry. However, poor interfacial compatibility between plant fibers and polypropylene (PP), as well as the performance deterioration under complex environmental aging conditions, severely limits their engineering applications. In this study, a synergistic interfacial modification strategy combining alkali treatment of hemp fibers (HFs) with polypropylene grafted maleic anhydride (PP-g-MAH) was employed to enhance fiber–matrix interaction. Hemp fiber-reinforced polypropylene composites (HFRPs) with varying fiber contents (7.5–30 wt%) were fabricated via injection molding. Accelerated aging tests were conducted on the compatibilized HFRPs for up to 2400 h under ultraviolet–thermal–moisture coupled conditions, in accordance with the SAE J2527 standard. The evolution of surface color, mechanical properties, chemical structure, and microstructure was systematically characterized. After aging, surface whitening of the composites was observed. Tensile strength and impact strength decreased by 9.57–22.12% and 38.68–46.03%, respectively, while flexural strength remained relatively stable due to the supporting effect of the fiber skeleton. The aging of compatibilized HFRPs follows an outside-in progressive degradation mechanism, characterized by a stepwise cascade of surface oxidation, crack propagation, moisture ingress, interfacial degradation, and mechanical performance deterioration. These findings offer valuable insights into the long-term durability of natural fiber-reinforced thermoplastic composites and provide theoretical and practical guidance for their structural design and application in demanding service environments.

Utilizing a recent observational dataset of particulate matter with diameters less than 2.5 µm (PM2.5) in North China, this study reveals a distinct seesaw feature of abnormally high and low PM2.5 concentrations in the adjacent two months of December 2015 and January 2016, accompanied by distinct meteorological modulations. The seesaw pattern is postulated to be linked to a super El Niño and the Arctic Oscillation (AO). During the mature phase of El Niño in December 2015, the weakened East Asian winter monsoon (EAWM) and the associated low-level southerly wind anomaly reduced planetary boundary layer (PBL) height, favoring strong haze formation. This circulation pattern was completely reversed in the following month, in part due to a sudden phase change of the AO from positive to negative and the beginning of a decay of the El Niño, which enhanced the southward shift of the upper tropospheric jet from December to January relative to climatology, leading to an enhanced EAWM and substantially lower haze formation. This sub-seasonal change in circulation is also robustly found in 1982–1983 and 1997–1998, implicative of a general physical mechanism dynamically linked to El Niño and the AO. Numerical experiments using the Weather Research and Forecasting (WRF) Community Multiscale Air Quality (CMAQ) model were used to test the modulation of the meteorological conditions on haze formation. With the same emission, simulations for three super El Niño periods (1983, 1997 and 2015) robustly show higher PM2.5  concentrations under the mature phase of the super El Niño, but substantially lower PM2.5 concentrations during the decay phase of El Niño (and the sudden AO phase change), further verifying the modulation effect of the sub-seasonal circulation anomaly on PM2.5 concentrations in North China.

A new antibody diagnostic assay with more rapid and robust properties is demanded to quantitatively evaluate anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity in a large population. Here, we developed a nanometer-scale fluorescent biosensor system consisting of CdSe-ZnS quantum dots (QDs) coupled with the highly sensitive B-cell epitopes of SARS-CoV-2 that could remarkably identify the corresponding antibody with a detection limit of 100 pM. Intriguingly, we found that fluorescence quenching of QDs was stimulated more obviously when coupled with peptides than the corresponding proteins, indicating that the energy transfer between QDs and peptides was more effective. Compared to the traditional enzyme-linked immunosorbent assay (ELISA), the B-cell-epitope-based QD-biosensor could robustly distinguish coronavirus disease 2019 (COVID-19) antibody-positive patients from uninfected individuals with a higher sensitivity (92.3–98.1% positive rates by QD-biosensor vs. 78.3–83.1% positive rates by ELISAs in 207 COVID-19 patients’ sera) in a more rapid (5 min) and labor-saving manner. Taken together, the ‘QD-peptides’ biosensor provided a novel real-time, quantitative, and high-throughput method for clinical diagnosis and home-use tests.

Retargeting the antigen-binding specificity of T cells to intracellular antigens that are degraded and presented on the tumor surface by engineering chimeric antigen receptor (CAR), also named TCR-like antibody CAR-T, remains limited. With the exception of the commercialized CD19 CAR-T for hematological malignancies and other CAR-T therapies aiming mostly at extracellular antigens achieving great success, the rareness and scarcity of TCR-like CAR-T therapies might be due to their current status and limitations. This review provides the probable optimized initiatives for improving TCR-like CAR-T reprogramming and discusses single-domain antibodies administered as an alternative to conventional scFvs and secreted by CAR-T cells, which might be of great value to the development of CAR-T immunotherapies for intracellular antigens.

Colloidal quantum dots (CQDs) are gaining increasing attention for gas sensing applications due to their large surface area and abundant active sites. However, traditional resistor-type gas sensors using CQDs to realize molecule recognition and signal transduction at the same time are associated with the trade-off between sensitivity and conductivity. This limitation has restricted their range of practical applications. In this study, we propose and demonstrate a monolithically integrated field-effect transistor (FET) gas sensor. This novel FET-type gas sensor utilizes the capacitance coupling effect of the CQD sensing film based on a floating gate, and the quantum capacitance plays a role in the capacitance response of the CQD sensing film. By effectively separating the gate sensing film from the two-dimensional electron gas (2DEG) conduction channel, the lead sulfide (PbS) CQD gate-sensitized FET gas sensor offers high sensitivity, a high signal-to-noise ratio, and a wide range, with a real-time response of sub-ppb NO2. This work highlights the potential of quantum dot-sensitized FET gas sensors as a practical solution for integrated gas sensor chip applications using CQDs.

Background Patients with cardiovascular comorbidities are at high risk of poor outcome from COVID-19. However, how the burden (number) of vascular risk factors influences the risk of severe COVID-19 disease remains unresolved. Our aim was to investigate the association of severe COVID-19 illness with vascular risk factor burden. Methods We included 164 (61.8 ± 13.6 years) patients with COVID-19 in this retrospective study. We compared the difference in clinical characteristics, laboratory findings and chest computed tomography (CT) findings between patients with severe and non-severe COVID-19 illness. We evaluated the association between the number of vascular risk factors and the development of severe COVID-19 disease, using a Cox regression model. Results Sixteen (9.8%) patients had no vascular risk factors; 38 (23.2%) had 1; 58 (35.4%) had 2; 34 (20.7%) had 3; and 18 (10.9%) had ≥4 risk factors. Twenty-nine patients (17.7%) experienced severe COVID-19 disease with a median (14 [7–27] days) duration between onset to developing severe COVID-19 disease, an event rate of 4.47 per 1000-patient days (95%CI 3.10–6.43). Kaplan-Meier curves showed a gradual increase in the risk of severe COVID-19 illness (log-rank P  < 0.001) stratified by the number of vascular risk factors. After adjustment for age, sex, and comorbidities as potential confounders, vascular risk factor burden remained associated with an increasing risk of severe COVID-19 illness. Conclusions Patients with increasing vascular risk factor burden have an increasing risk of severe COVID-19 disease, and this population might benefit from specific COVID-19 prevention (e.g., self-isolation) and early hospital treatment measures.

Colloidal quantum dots (CQDs) are gaining increasing attention for gas sensing applications due to their large surface area and abundant active sites. However, traditional resistor-type gas sensors using CQDs to realize molecule recognition and signal transduction at the same time are associated with the trade-off between sensitivity and conductivity. This limitation has restricted their range of practical applications. In this study, we propose and demonstrate a monolithically integrated field-effect transistor (FET) gas sensor. This novel FET-type gas sensor utilizes the capacitance coupling effect of the CQD sensing film based on a floating gate, and the quantum capacitance plays a role in the capacitance response of the CQD sensing film. By effectively separating the gate sensing film from the two-dimensional electron gas (2DEG) conduction channel, the lead sulfide (PbS) CQD gate-sensitized FET gas sensor offers high sensitivity, a high signal-to-noise ratio, and a wide range, with a real-time response of sub-ppb NO[sub.2] . This work highlights the potential of quantum dot-sensitized FET gas sensors as a practical solution for integrated gas sensor chip applications using CQDs.

A fault diagnosis based on bond graph model is proposed for hydraulic variable pitch system. Because the knowledge representation of bond graph model can provide information of cause and effect between components, a bond graph model of hydraulic variable pitch system is given above rated wind speed. A fault tree, using cause and effect analysis by back propagation, is developed. Qualitative value of parameters is assigned and the fault source is detected by analyzing boundary parameters of fault tree. Comparing with quantitative fault diagnosis based on model, the bond graph fault diagnosis is more flexible and has good completeness.