摘要：
Due to the low storage cost and high computation efficiency of hashing, cross-modal hashing has been attracting widespread attention in recent years. In this paper, we investigate how supervised cross-modal hashing (CMH) benefits from multi-label and contrastive learning (CL) by overcoming the following two challenges: (i) how to combine multi-label and supervised contrastive learning to consider diverse relationships among cross-modal instances, and (ii) how to reduce the sparsity of multi-label representation so as to improve the similarity measurement accuracy. To this end, we propose a novel cross-modal hashing framework, dubbed Multi-Label Weighted Contrastive Hashing (MLWCH). This framework involves compact consistent similarity representation, a new designed multi-label similarity calculation method that efficiently reduces the sparsity of multi-label by reducing redundant zero elements. Furthermore, a novel multi-label weighted contrastive learning strategy is developed to significantly improve hashing learning by assigning similarity weight to positive samples under both linear and non-linear similarities. Extensive experiments and ablation analysis over three benchmark datasets validate the superiority of our MLWCH method, especially over several outstanding baselines.
摘要：
Ampelopsis grossedentata, commonly known as "Vine Tea" and well-recognized for its rich flavonoid content, is mainly distributed in the southern regions of the Yangtze River basin in China. These regions include Hunan, Hubei, Jiangxi, and Guizhou provinces. Vine Tea is mainly consumed as an herbal tea and has garnered attention for its reported health benefits, including antioxidant, anti-inflammatory, anti-tumor, anti-diabetic, and neuroprotective properties. It has been used to alleviate coughs and sore throats (Zhang et al., 2021; Wang et al., 2017; Gao et al., 2009). In the Zhangjiajie region of Hunan province alone, the Vine Tea planting area reached 7,670.5 hectares and produced commercial goods worth 1.417 billion RMB in 2022. In May 2021, leaf margins and veins fading to yellowing mottling, and crumpling of leaf blades in the shape of a boat symptoms were found in ~16% of Vine Tea plants in the Sanjiakuan Township, Yongding District, Zhangjiajie region (29°15'E, 110°30' N) (Figure 1a, b, c). (Figure 1a, b, c). Phytoplasma-like microbial cells (small oval shaped bacterial cells, around 1000 nm in size) were observed in sieve tube cells in the phloem of diseased leaves using transmission electron microscopy. No such cell was observed in the phloem of healthy leaves (Figure 2a, b). To investigate the potential association between phytoplasma and the observed symptoms of the diseased plants, total DNA was isolated from ten diseasedeaves and compared with ten healthy leaves from the same field using SteadyPure Plant Genomic DNA Extraction Kit. The isolated DNAs were analyzed first in a direct PCR using universal phytoplasma primer pair R16mF2/R16mR1 targeting the 16S rRNA gene (Gundersen and Lee 1996) and specific pair rpF1/rpR1 (Lee et al. 1998) targeting the DNA fragment encoding partial ribosomal proteins (rp) L22 (complete) and S3 and S19 (partial). The initial amplified products were used as templates and further amplified by nested PCR respectively with primer pair R16F2n/R16R2 for the 16S rRNA gene (Lee et al. 1998) and the rpF2/rpR2 primer pair for the rp gene (Martini et al. 2007). No amplification was obtained with DNA from healthy leaf samples using any of the four primer pairs. The amplified fragments from diseased leaves by nested PCR were cloned and sequenced (Qingke Biotech, China). The obtained sequences have been deposited in GenBank with accession numbers OR282806 for the 16S rRNA gene and GenBank OR353012 for the rp gene. BLASTn analysis revealed that the partial 16S rRNA gene sequence in our sample shared 99.4% nucleotide sequence identity with 'Candidatus Phytoplasma sp.' (MW364378) and 'Peony yellows phytoplasma' (KY814723) of the 16SrI group. Similarly, our rp gene sequence shared 99.6% nucleotide identity with the rpI group of phytoplasma such as the 'Balsamine virescence phytoplasma' (JN572890) and 'Paulownia witches'-broom phytoplasma' (HM146079). Phylogenetic analysis of the 16S rRNA and rp sequences using MEGA version 7.0 revealed that the phytoplasma strain associated with A. grossedentata yellow leaf syndrome in our study site belonged to the 16SrI (Candidatus Phytoplasma asteris) group of phytoplasma (Figure 3a, b). Using the interactive online phytoplasma classification tool iPhyClassifier (Zhao et al., 2009), virtual restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene sequences showed our strain having a distinct RFLP map but was closest to that of the onion yellow phytoplasma 16SrI-B subgroup (GenBank accession number: AP006628), with a similarity coefficient of 0.94 (Figure 4a, b). To confirm phytoplasma transmission, healthy plants were inoculated with three scions of infected plants of A. grossedentata. After 16 days, the new leaves of the inoculated A. grossedentata showed yellow leaf symptoms (Figure 5a, b, c), akin to the symptoms originally observed in the field, and the outer contour of the leaf margin appeared chlorotic. After 26 days, primer pairs R16mF2/R16R1 and R16F2n/R16R2 were used for nested PCR detection of phytoplasma in symptomatic A. grossedentata leaves. Phytoplasma was detected in the first and second leaves of symptomatic branches and leaves while negative control showed no amplification. Sequencing of the amplified fragments showed 100% nucleotide identity to the strain from the grafting source. Our results indicated that the pathogen and the disease can be transmitted by tissue grafting, consistent with the biological characteristics of phytoplasma, and further confirmed that the phytoplasma was the pathogen of yellow leaf syndrome of A. grossedentata. Toour knowledge, this is the first report of phytoplasma of group 16SrI affecting A. grossedentata.
摘要：
Simple Summary: The intestinal health problems of weaned piglets cause serious economic losses. Historically, antibiotics have been used to prevent and treat intestinal problems in weaned piglets. However, the prohibition of antibiotics makes us need to find a safer and effective solution strategy. A large number of studies have shown that the endocannabinoid system, as a lipid mediator signaling system widely distributed in the gastrointestinal tract, interacts with the intestinal microbiota and maintains intestinal homeostasis. In this study, we found that the endocannabinoid system is closely related to the abundance of Lactobacillus johnsonii through a piglet antibiotic model. It was further found that Lactobacillus johnsonii could improve intestinal health problems and alleviate piglet diarrhea. At the same time, its ability to regulate the endocannabinoid system was verified, and the correlation analysis found that its benefits are partly achieved through the participation of the endocannabinoid system. Probiotic intervention is a well-established approach for replacing antibiotics in the management of weaning piglet diarrhea, which involves a large number of complex systems interacting with the gut microbiota, including the endocannabinoid system; nevertheless, the specific role of the endocannabinoid system mediated by probiotics in the piglet intestine has rarely been studied. In this study, we used antibiotics (ampicillin) to perturb the intestinal microbiota of piglets. This resulted in that the gene expression of the intestinal endocannabinoid system was reprogrammed and the abundance of probiotic Lactobacillus johnsonii in the colon was lowered. Moreover, the abundance of Lactobacillus johnsonii was positively correlated with colonic endocannabinoid system components (chiefly diacylglycerol lipase beta) via correlation analysis. Subsequently, we administered another batch of piglets with Lactobacillus johnsonii. Interestingly, dietary Lactobacillus johnsonii effectively alleviated the diarrhea ratio in weaning piglets, accompanied by improvements in intestinal development and motility. Notably, Lactobacillus johnsonii administration enhanced the intestinal barrier function of piglets as evidenced by a higher expression of tight junction protein ZO-1, which might be associated with the increased level in colonic diacylglycerol lipase beta. Taken together, the dietary Lactobacillus johnsonii-mediated reprogramming of the endocannabinoid system might function as a promising target for improving the intestinal health of piglets.
摘要：
Pre-parasitic second-stage juveniles (pre-J2s) of Meloidogyne graminicola are non-feeding in soil, and their migration, localization and successful invasion of host roots are essential for survival. Chemotaxis is thought to play a central role in host localization, but the mechanisms of chemotaxis are poorly understood. In this study, we cloned and evaluated the molecular characteristics and functions of four chemosensory genes, including Mg-odr-3, Mg-odr-1, Mg-tax-4, and Mg-osm-9. Quantitative real-time PCR (qRT-PCR) analysis revealed that Mg-odr-3 and Mg-osm-9 tended to be expressed in pre-J2s and parasitic J2s (par-J2s), while Mg-odr-1 and Mg-tax-4 were expressed in par-J2s, consistent with their functions during the host-seeking period and establishment of suitable feeding sites in root tips. Root signals from eight plant root extracts, namely, rice, barnyard grass (Echinochloa crus-galli), wheat, soybean, pepper, tomato, eggplant, and marigold, were repulsive to J2s of M. graminicola. Moreover, RNAi silencing of Mg-odr-3, Mg-odr-1, Mg-tax-4, and Mg-osm-9 in J2s attenuated their repulsion to the rice root extract. Furthermore, we found that the response of J2s to root exudates was concentration-dependent, with high concentrations of root exudates repelling J2s. Silenced J2s also showed reduced repulsion in response to high concentrations of rice root exudates. Conversely, M. graminicola J2s were attracted to the root tips of the eight plants, while RNAi-J2s showed defective attraction to root tips. In conclusion, our results showed that chemosensory genes are crucial for the chemotactic host-seeking behaviour of M. graminicola.
摘要：
Background: Selenium is an essential trace element for human health and its deficiency leads to increased risk of many diseases worldwide. Tea (Camellia sinensis (L.) O. Kuntze) is a plant with selenium accumulation ability. Selenium-enriched tea combines the flavor and health benefits of tea with the additional wellness advantages of selenium, holding promising market potential. Scope and approach: This article reviews the latest research advances on selenium-enriched tea. The ability and mechanism of selenium accumulation in tea plants, as well as the existence forms of selenium in tea leaves, have been summarized. In addition, we examined the effects of selenium on tea physiological activities, including metabolic and quality regulation, and provided a summary of the associated health benefits. Key findings and conclusions: Tea plants possess a strong ability to accumulate selenium in selenium-rich area or under selenium fertilizer application. Over 80% of the selenium in selenium-enriched tea leaves exists in organic forms, including selenoamino acids, selenoproteins, selenium-polysaccharides, and selenium-polyphenols. Selenium can promote tea growth and optimize the proportion of quality compounds (e.g., polyphenols, amino acids, and alkaloids). The levels of stress-related antioxidant enzymes and phytohormones are increased to promote environmental stress resistance and selenium tolerance. Selenium-enriched tea demonstrates superior health benefits compared to regular tea due to the synergistic effects of tea active ingredients and selenium element. This review aims to inspire innovative ideas for the development of selenium-enriched tea with thriving growth conditions, high selenium bioaccessibility, delightful flavor, and broad applications in the food and health industries.
摘要：
The phenylalanine ammonia-lyase (PAL) enzyme catalyses the conversion of l-phenylalanine to trans-cinnamic acid. This conversion is the first step in phenylpropanoid biosynthesis in plants. The phenylpropanoid pathway produces diverse plant metabolites that play essential roles in various processes, including structural support and defence. Previous studies have shown that mutation of the PAL genes enhances disease susceptibility. Here, we investigated the functions of the rice PAL genes using 2-aminoindan-2-phosphonic acid (AIP), a strong competitive inhibitor of PAL enzymes. We show that the application of AIP can significantly reduce the PAL activity of rice crude protein extracts in vitro. However, when AIP was applied to intact rice plants, it reduced infection of the root-knot nematode Meloidogyne graminicola. RNA-seq showed that AIP treatment resulted in a rapid but transient upregulation of defence-related genes in roots. Moreover, targeted metabolomics demonstrated higher levels of jasmonates and antimicrobial flavonoids and diterpenoids accumulating after AIP treatment. Furthermore, chemical inhibition of the jasmonate pathway abolished the effect of AIP on nematode infection. Our results show that disturbance of the phenylpropanoid pathway by the PAL inhibitor AIP induces defence in rice against M. graminicola by activating jasmonate-mediated defence.
摘要：
The quality of pasteurized milk is commonly assessed through microbiological analysis, with variations in storage conditions significantly impacting the suppression of bacterial growth throughout the milk's shelf life. This study investigated the dynamics of total bacterial counts (TBCs) and bacterial community shifts in milk that underwent pasteurization at 80 °C for 15 s. The milk was subsequently stored at 4 °C for varying intervals of 1, 4, 7, 10, 13, and 16 days. Culture-based testing revealed a significant TBC increase during the storage period spanning 1 to 16 days (up to -log10 4.2 CFU/mL at day 16). The TBC in pasteurized milk exhibited accelerated microbial growth from day 13 onwards, ultimately peaking on day 16. Bacillus was detected through 16S rRNA identification. Principal component analysis demonstrated a significant impact of storage time on bacterial communities in pasteurized milk. Analysis of bacterial diversity revealed a negative correlation between the Shannon index and the duration of pasteurized milk storage. Using high-throughput sequencing, Streptococcus and Acinetobacter were detected as prevalent bacterial genera, with Streptococcus dysgalactiae and Streptococcus uberis showing as dominant taxa. The presence of Streptococcus dysgalactiae and Streptococcus uberis in pasteurized milk might be attributed to the initial contamination from raw milk with mastitis. This study offers new evidence of the prevalence of bacterial community in pasteurized milk, thereby adding value to the enhancement of quality control and the development of strategies for reducing microbial risks.
摘要：
Fu brick tea (FBT) has unique "fungal flower" aroma traits, but its source of crucial aroma compounds is still controversial. Aspergillus cristatus is the dominant fungus that participated in the fermentation of FBT. In this study, volatiles of Aspergillus cristatus and corresponding fermented FBT were examined using GC×GC-Q-TOFMS. A total of 59 volatiles were shared by three strains of Aspergillus cristatus isolated from representative FBT. Among them, 1-octen-3-ol and 3-octanone were the most abundant. A total of 133 volatiles were screened as typical FBT volatiles from three FBTs fermented by the corresponding fungi. Aspergillus cristatus and FBT had only 29 coexisting volatiles, indicating that the volatiles of Aspergillus cristatus could not directly contribute to the aroma of FBT. The results of no significant correlation between volatile content in FBT and volatile content in Aspergillus cristatus suggested that intracellular metabolism of Aspergillus cristatus was not a direct driver of FBT aroma formation. Metabolic pathway analysis and proteomic analysis showed that the aroma in FBT was mainly formed by the enzymatic reaction of extracellular enzymes from Aspergillus cristatus. This study enriched our understanding of Aspergillus cristatus in the aroma formation process of FBT.
摘要：
In order to explore the effect of fertilization patterns on the growth of rapeseed seedlings under waterlogging stress, three fertilization patterns (conventional fertilization, supplemental organic fertilization, and supplemental microbial fertilization) were set up using the variety Xiangyou 708 as the material, and waterlogging treatment was carried out during the seedling stage of rapeseed. The effects of fertilization patterns on the growth of rapeseed seedlings and rhizosphere microorganisms under waterlogging stress were investigated. The results showed that all three fertilization patterns exhibited that waterlogging stress inhibited the growth of rapeseed seedlings, inhibited root activity, and changed the structure of rhizosphere bacterial community structure. However, supplemental organic and microbial fertilization better promoted the growth of rapeseed seedlings, reduced the impact of waterlogging stress on the growth of rapeseed seedlings, and accelerated the recovery of rapeseed seedlings after waterlogging stress. Under normal water supply, supplemental organic fertilization enriched P_Bacteroidota, P_Actinobacteriota, P_Chloroflexi, and G_Flavisolibacter in the rhizosphere soil of rapeseed, while supplemental microbial fertilization enriched P_Bacteroidota and G_Flavisolibacter in the rhizosphere soil of rapeseed. After 7 days of waterlogging treatment, supplemental organic fertilization enriched P_Verrucomicrobiota in the rhizosphere soil of rapeseed, while supplemental microbial fertilization enriched P_Actinobacteriota, G_SC-I-84, and G_Ellin6067 in the rhizosphere soil of rapeseed. The enrichment of these bacteria may be related to the growth promotion and waterlogging tolerance of rapeseed. This study provides evidence that microbial and organic fertilizer can promote the growth of rapeseed and enhance its waterlogging tolerance, as well as evidence that some rhizosphere microorganisms have a potential role in promoting the growth and waterlogging tolerance of rapeseed.
摘要：
High-density intensive farming accelerates the incidence and transmission risk of various infectious diseases in poultry. The development and application of medicinal herbs, probiotics, and other feed additives have gathered a lot of attention in the context of the total ban on antibiotic feed additives and healthy breeding. This study investigated the effects of dietary Terminalia chebula extract (TCE), a plant extract, on growth performance, immune function, antioxidant capacity, and intestinal health in yellow-feathered broilers. Our findings demonstrated that TCE could improve broilers' immune function, antioxidant capacity, intestinal health, and growth performance. The mechanism for the beneficial effect of TCE supplementation was not limited to the enhancement of the immune response and antioxidant capacity, as there was also an improvement in intestinal health due to TCE enhancing beneficial bacteria, promoting intestinal short-chain fatty acid secretion, and improving intestinal morphology. This improvement in intestinal health ultimately resulted in the improved health status of the yellow-feathered broilers. These findings provide a basis and reference for Terminalia chebula extract as an effective feed additive in broiler breeding. Terminalia chebula extract (TCE) has many physiological functions and is potentially helpful in maintaining poultry health, but its specific effect on the growth of broilers is not yet known. This research investigated the effects of dietary Terminalia chebula extract (TCE) supplementation on growth performance, immune function, antioxidant capacity, and intestinal health in yellow-feathered broilers. A total of 288 one-day-old yellow-feathered broilers were divided into four treatment groups (72 broilers/group), each with six replicates of 12 broilers. The broilers were given a basal diet of corn-soybean meal supplemented with 0 (control), 200, 400, and 600 mg/kg TCE for 56 d. The results demonstrated that, compared with the basal diet, the addition of TCE significantly increased (linear and quadratic, p < 0.05) the final body weight and overall weight gain and performance and decreased (linear and quadratic, p < 0.05) the feed-to-gain ratio in the overall period. Dietary TCE increased (linear, p < 0.05) the levels of IgM, IL-4, and IL-10 and decreased (linear and quadratic, p < 0.05) the level of IL-6 in the serum. Dietary TCE increased (linear and quadratic, p < 0.05) the levels of IL-2 and IL-4, decreased (linear and quadratic, p < 0.05) the level of IL-1 beta, and decreased (linear, p < 0.05) the level of IL-6 in the liver. Dietary TCE increased (linear and quadratic, p < 0.05) the level of IgM and IL-10, increased (linear, p < 0.05) the level of IgG, and decreased (linear and quadratic, p < 0.05) the levels of IL-1 beta and IL-6 in the spleen. Supplementation with TCE linearly and quadratically increased (p < 0.05) the catalase, superoxide dismutase, glutathione peroxidase, and total antioxidant capacity activities while decreasing (p < 0.05) the malonic dialdehyde concentrations in the serum, liver, and spleen. TCE-containing diets for broilers resulted in a higher (linear and quadratic, p < 0.05) villus height, a higher (linear and quadratic, p < 0.05) ratio of villus height to crypt depth, and a lower (linear and quadratic, p < 0.05) crypt depth compared with the basal diet. TCE significantly increased (linear, p < 0.05) the acetic and butyric acid concentrations and decreased (quadratic, p < 0.05) the isovaleric acid concentration. Bacteroidaceae and Bacteroides, which regulate the richness and diversity of microorganisms, were more abundant and contained when TCE was added to the diet. In conclusion, these findings demonstrate that supplementing broilers with TCE could boost their immune function, antioxidant capacity, and gut health, improving their growth performance; they could also provide a reference for future research on TCE.
期刊：
Environment, Development and Sustainability,2024年 ISSN：1387-585X
通讯作者：
Chen, JY
作者机构：
[Dong, Xuesong] Hunan Agr Univ, Sch Business, Changsha 410083, Peoples R China.;[Chen, Jinyu; Huang, Jianbai] Cent South Univ, Sch Business, Changsha 410083, Peoples R China.;[Chen, Jinyu; Dong, Xuesong; Huang, Jianbai] Cent South Univ, Inst Met Resources Strategy, Changsha 410083, Peoples R China.
通讯机构：
[Chen, JY ] C;Cent South Univ, Sch Business, Changsha 410083, Peoples R China.;Cent South Univ, Inst Met Resources Strategy, Changsha 410083, Peoples R China.
关键词：
Metal consumption;Input-output analysis;Structural path analysis;Structural decomposition analysis
摘要：
The dependence of economic development on the metal resource is one of the challenges for developing countries. Given the enormous pressure of resource shortage in China, exploring the flow of metals between sectors is critical to achieve the Sustainable Development Goals. Based on the Chinese environmentally extended input-output (CEEIO) database from 1997 to 2017, the structural decomposition analysis (SDA) and the structural path analysis (SPA) models were combined to analyze the main driving factors and key paths of metal consumption in China. The results show that from 1997 to 2017, China's economic development and metal consumption presented states of weak decoupling and expansion coupling. Capital formation, consumption expansion, and export expansion were main drivers of metal consumption. Sectors such as metal smelting, construction, and other manufacturing products consumed a large amount of metal directly or provide intermediate products for other sectors. In the future, the upstream and downstream links of the industrial chain should be managed according to the key path, so as to optimize the structure of intermediate products and final demand and realize metal resources conservation from production to consumption.
摘要：
Being a destructive pest worldwide, the whitefly Bemisia tabaci has evolved resistance to neonicotinoid insecticides. The third-generation neonicotinoid dinotefuran has commonly been applied to the control of the whitefly, but its underlying mechanism is currently unknown. On the base of our transcriptome data, here we aim to investigate whether the cytochrome P450 CYP6EM1 underlies dinotefuran resistance in the whitefly. Compared to the susceptible strain, the CYP6EM1 gene was found to be highly expressed in both laboratory and field dinotefuran-resistant populations. Upon exposure to dinotefuran, the mRNA levels of CYP6EM1 were increased. These results demonstrate the involvement of this gene in dinotefuran resistance. Loss and gain of functional studies in vivo were conducted through RNAi and transgenic Drosophila melanogaster assays, confirming the role of CYP6EM1 in conferring such resistance. In a metabolism assay in vitro, the CYP6EM1 protein could metabolize 28.11% of dinotefuran with a possible dinotefuran-dm-NNO metabolite via UPLC-QTOF/MS. Docking of dinotefuran to the CYP6EM1 protein showed a good binding affinity, with an energy of less than -6.0 kcal/mol. Overall, these results provide compelling evidence that CYP6EM1 plays a crucial role in the metabolic resistance of B. tabaci to dinotefuran. Our work provides new insights into the mechanism underlying neonicotinoid resistance and applied knowledge that can contribute to sustainable control of a global pest such as whitefly.
作者机构：
[Xiao, Xiao; Lu, Bingyi; Wang, Boran; Mao, Rui; Liu, Yingqi; Zhou, Guangmin; Lu, Gongxun; Song, Yanze] Tsinghua Univ, Tsinghua Berkeley Shenzhen Inst, Shenzhen 518055, Peoples R China.;[Xiao, Xiao; Lu, Bingyi; Wang, Boran; Mao, Rui; Liu, Yingqi; Zhou, Guangmin; Lu, Gongxun; Song, Yanze] Tsinghua Univ, Tsinghua Shenzhen Int Grad Sch, Shenzhen 518055, Peoples R China.;[Yang, JL; Lu, Bingyi; Yang, Jinlong] Shenzhen Univ, Coll Mat Sci & Engn, Guangdong Res Ctr Interfacial Engn Funct Mat, Shenzhen Key Lab Energy Electrocatalyt Mat, Shenzhen 518060, Peoples R China.;[Min, Zhiwen; Sun, YM; Sun, Yuanmiao] Chinese Acad Sci, Fac Mat Sci & Energy Engn, Shenzhen Inst Adv Technol, Inst Technol Carbon Neutral, Shenzhen 518055, Peoples R China.;[Chen, Biao] Tianjin Univ, Sch Mat Sci & Engn, Tianjin 300350, Peoples R China.
通讯机构：
[Yang, JL ] S;[Sun, YM ] C;[Zhou, GM ] T;Tsinghua Univ, Tsinghua Berkeley Shenzhen Inst, Shenzhen 518055, Peoples R China.;Tsinghua Univ, Tsinghua Shenzhen Int Grad Sch, Shenzhen 518055, Peoples R China.
关键词：
bidirectional catalysts;in-built electric fields;Li-CO2 batteries;overpotential;spent lithium-ion batteries
摘要：
Lithium-carbon dioxide (Li-CO2) batteries are regarded as a prospective technology to relieve the pressure of greenhouse emissions but are confronted with sluggish CO2 redox kinetics and low energy efficiency. Developing highly efficient and low-cost catalysts to boost bidirectional activities is craved but remains a huge challenge. Herein, derived from the spent lithium-ion batteries, a tandem catalyst is subtly synthesized and significantly accelerates the CO2 reduction and evolution reactions (CO2RR and CO2ER) kinetics with an in-built electric field (BEF). Combining with the theoretical calculations and advanced characterization techniques, this work reveals that the designed interface-induced BEF regulates the adsorption/decomposition of the intermediates during CO2RR and CO2ER, endowing the recycled tandem catalyst with excellent bidirectional activities. As a result, the spent electronics-derived tandem catalyst exhibits remarkable bidirectional catalytic performance, such as an ultralow voltage gap of 0.26 V and an ultrahigh energy efficiency of 92.4%. Profoundly, this work affords new opportunities to fabricate low-cost electrocatalysts from recycled spent electronics and inspires fresh perceptions of interfacial regulation including but not limited to BEF to engineer better Li-CO2 batteries.
摘要：
The cadmium (Cd) accumulates in birnessite as it forms on the surface of paddy crusts (PC). The stability of Cd-containing birnessite is influenced by environmental factors, and destabilized birnessite releases dissolved Cd. We report the effects of pH, oxalic acid, and light on the dissolution of Cd-containing birnessite. We found that at pH 4.0, with light and 0.20 mol/L oxalic acid, the ratio of dissolved Cd and manganese (Mn) peaked after 24 h at 2978.0 mu g/g and 326.8 mg/g, respectively. The three environmental factors affected the dissolution of Cd-containing birnessite in the following order: pH > oxalic acid > light. During dissolution process, Cd and Mn did not dissolve simultaneously, and the dissolved Cd/Mn ratio in the solution was significantly lower than that of the pristine mineral (33.5 x 10(-3)). Compared with Mn, Cd dissolution was inhibited by strong acidity (pH 4.0-5.0), and the dissolved Cd/Mn ratio was 5-10 x 10(-3). Mild acidity (pH 6.0) was weakly inhibitory, with a Cd/Mn ratio of 6-15 x 10(-3). In an alkaline (pH 8.0) oxalate environment, light illumination inhibited Cd dissolution, and the Cd/Mn ratio decreased over time due to the stability of the products formed by oxalate and carbonate, with Cd being more stable than those formed by Mn. Our findings would provide insights into the migration and transformation of PC-associated Cd in paddy fields.
摘要：
Lilium growth is severely impeded by continuous cropping, and crop rotation is essential to reducing the detrimental effects of monocultures. Soil (0-20 cm) was collected in three Lilium cropping patterns in Longshan County, Hunan Province, including continuous Lilium cropping (Lilium), corn upland rotation with Lilium (Corn), and paddy rotation with Lilium (Rice). Using Illumina high-throughput sequencing technology, the fungal ribosomal DNA internal-transcribed spacer 1 (ITS1) was examined to evaluate the features of soil fungi communities among three cropping patterns. Crop rotation has an impact on soil properties and the microbial community. Rice soil has a significantly higher pH than Lilium and corn soil, while corn and rice soil have a greater total nitrogen and total phosphorus content than Lilium soil. Rotation cropping clearly shifted the fungi community diversity based on the results of principal coordinate analysis (PCoA) and nonmetric multidimensional scaling (NMDS). Ascomycota was the most prevalent phylum, with the highest levels in Lilium soil. Genetic analysis revealed that paddy rotation led to a clear reduction in or non-detection of eight potentially pathogenic fungal genera and a noticeable accumulation of eight beneficial fungal genera compared to Lilium continuous cropping. Fungi communities and their abundant taxa were correlated with soil pH and nutrients. Altogether, we propose that rice rotation, with its ability to mitigate soil acidification, reducing pathogenic and accumulating beneficial communities, may be an effective strategy for alleviating the continuous cropping barrier.
关键词：
Paddy soil;Type I and II methanotrophs;Methane oxidation rate;Carbon conversion efficiency;PLFA-SIP;Climate zones;Soil pH
摘要：
Conventional aerobic methanotrophs oxidize methane (CH4) and covert CH4-derived carbon (C) into biomass at the oxic-anoxic interface of inundated rice paddy fields, playing indispensable role in mitigating greenhouse gas emissions and loss of organic C from methanogenesis. Two phylogenetically distinct groups of methanotrophs, type I (gamma-proteobacteria) and type II (alpha-proteobacteria) methanotrophs, often co-exist in rice paddy soil and compete for CH4 biotransformation. Since these two methanotrophic groups also possess differential kinetics of CH4 oxidation and pathways of C assimilation, the consequence of their niche differentiation and metabolic differences in soil is expected to affect the CH4 oxidation rate and C conversion efficiency. Here, we examined the microbiology, chemistry, and CH4 metabolism in 24 geographically different paddy soils, covering four climate zones of eastern China. High-throughput sequencing of pmoA gene displayed a clear separation of in situ methanotrophic compositions between temperate (warm and mid-temperate) and warmer (subtropics and tropics) climate zones, likely driven by soil pH. Both methanotrophic groups were detected in soils but proportions of type I methanotrophs increased in temperate soils of higher pH (accounting for 76.1 +/- 12.4% and 44.1 +/- 14.8% in warm temperate and mid-temperate, respectively). Type II methanotrophs prevailed in warmer zones (accounting for 66.2 +/- 21.6% and 70.5 +/- 12.1% in tropics and subtropics, respectively) where soils were more acidic. Higher incorporation of 13C for synthesis in C14+C16 PLFAs (63.1-93.4% of total production of 13C-PLFAs) was found based on microcosm incubation, reflecting type I methanotrophs dominated the CH4 assimilation in paddy soils. Particularly, temperate soils with increased proportions of type I methanotrophs showed higher CH4 oxidation rate and C conversion efficiency. Collectively, this study depicts a continental-scale disparity of methanotrophic dynamics that tightly associates with consequence of niche differentiation of different types of methanotrophs and highlights the importance of microbiological control to maximize the rate and efficiency of methanotrophy.
摘要：
Understanding the yield attributes of the popular rice (Oryza sativa L.) hybrids can provide useful information for developing new hybrid rice varieties. Field experiments were conducted at two subtropical sites (Hengyang and Xingyi) in two years (2021 and 2022) to compare grain yield and yield attributes of three currently popular hybrid rice varieties (Jingliangyouhuazhan, Jingliangyou 534, and Longliangyouhuazhan) with three representative super hybrid rice varieties (Y-liangyou 1, Y-liangyou 2, and Y-liangyou 900). No significant differences in grain yield were observed between the group of popular hybrids and the group of super hybrids at Hengyang and Xingyi in 2021 or at Xingyi in 2022, but at Hengyang in 2022, the group of popular hybrids produced a 15% higher grain yield. The grain yield at Hengyang in 2022 was lower than that at Hengyang and Xingyi in 2021 and at Xingyi in 2022. At Hengyang in 2022, the group of popular hybrids had 9-15% higher panicles per m2, spikelet filling percentage, and harvest index but similar spikelets per panicle and total biomass production and 12% lower grain weight compared to the group of super hybrids. Correlation plot analysis showed that grain yield was significantly related to panicles per m2 but not other yield attributes across six varieties at Hengyang in 2022. These results indicated that the currently popular hybrid rice varieties had higher yield performance than the representative super hybrid rice varieties under the condition of relatively lower productivity, and the key factor for this higher yield performance in the popular hybrids was the higher panicles per m2. This finding highlights that more attention should focus on the yield performance under medium- and low-productivity conditions in hybrid rice breeding programs, and an effective breeding strategy is to select the varieties with high panicle numbers.
关键词：
RNA barcode segments;SARS-CoV-2 variants and related lineages;HCoVs;Genetic tests;Complete genome sequences
摘要：
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen responsible for coronavirus disease 2019 (COVID-19), continues to evolve, giving rise to more variants and global reinfections. Previous research has demonstrated that barcode segments can effectively and cost-efficiently identify specific species within closely related populations. In this study, we designed and tested RNA barcode segments based on genetic evolutionary relationships to facilitate the efficient and accurate identification of SARS-CoV-2 from extensive virus samples, including human coronaviruses (HCoVs) and SARSr-CoV-2 lineages. Nucleotide sequences sourced from NCBI and GISAID were meticulously selected and curated to construct training sets, encompassing 1733 complete genome sequences of HCoVs and SARSr-CoV-2 lineages. Through genetic-level species testing, we validated the accuracy and reliability of the barcode segments for identifying SARS-CoV-2. Subsequently, 75 main and subordinate species-specific barcode segments for SARS-CoV-2, located in ORF1ab, S, E, ORF7a, and N coding sequences, were intercepted and screened based on single-nucleotide polymorphism sites and weighted scores. Post-testing, these segments exhibited high recall rates (nearly 100%), specificity (almost 30% at the nucleotide level), and precision (100%) performance on identification. They were eventually visualized using one and two-dimensional combined barcodes and deposited in an online database (http://virusbarcodedatabase.top/). The successful integration of barcoding technology in SARS-CoV-2 identification provides valuable insights for future studies involving complete genome sequence polymorphism analysis. Moreover, this cost-effective and efficient identification approach also provides valuable reference for future research endeavors related to virus surveillance.
摘要：
This study aimed to develop a systematic method for assessing the cold tolerance of broccoli seedlings, which is helpful to evaluating the cold tolerance of broccoli cultivars. We selected 14 classical broccoli cultivars and evaluated their cold tolerance by examining physiological indicators including the levels of cold resistance, electrical conductivity, malondialdehyde (MDA), soluble sugar, and hydrogen peroxide (H2O2). The results showed that there were significant differences in detected characteristics in all cultivars after cold stress during the seedling stage (p < 0.05). Among them, Meiqing had the strongest cold tolerance, followed by King 11, Zhongqing 15, Meiao 7172, Zhongqing 318, Zheqing 80, Zhongqing 16, Zhongqing 319, and Lvxiong 90. However, Zhongqing 11, Yanxiu, Qianghan, and Feicui 5, showed the worst cold tolerance (all died). Pearson correlation analysis indicated that there was a significantly negative correlation between the cold tolerance and the electrical conductivity during broccoli seedling stage, with a correlation coefficient of -0.586 (p < 0.05). At the same time, we found that the electrical conductivity of all broccoli cultivars showed a positive correlation with the MDA and soluble sugar levels, with the correlation coefficients 0.650 and 0.573, respectively (p < 0.05). This study not only firstly provides a fundamental method for evaluating the cold tolerance in different broccoli genotypes and the other cruciferous vegetables, but also offers a scientific evidence explaining the cold tolerance of the Meiqing, King 11, and Zhongqing 15 cultivars widely cultivated in China.
