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1.
Nat Commun ; 15(1): 8281, 2024 Sep 27.
Article de Anglais | MEDLINE | ID: mdl-39333612

RÉSUMÉ

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), reduces wheat yields and grain quality, thus posing a significant threat to global food security. Wild relatives of wheat serve as valuable resources for resistance to powdery mildew. Here, the powdery mildew resistance gene Pm6Sl is cloned from the wild wheat species Aegilops longissima. It encodes a nucleotide-binding leucine-rich repeat (NLR) protein featuring a CC-BED module formed by a zinc finger BED (Znf-BED) domain integrated into the coiled-coil (CC) domain. The function of Pm6Sl is validated via mutagenesis, gene silencing, and transgenic assays. In addition, we develop a resistant germplasm harbouring Pm6Sl in a very small segment with no linkage drag along with the diagnostic gene marker pm6sl-1 to facilitate Pm6Sl deployment in wheat breeding programs. The cloning of Pm6Sl, a resistance gene with BED-NLR architecture, will increase our understanding of the molecular mechanisms underlying BED-NLR-mediated resistance to various pathogens.


Sujet(s)
Aegilops , Ascomycota , Résistance à la maladie , Protéines NLR , Maladies des plantes , Protéines végétales , Triticum , Triticum/microbiologie , Triticum/génétique , Triticum/immunologie , Maladies des plantes/microbiologie , Maladies des plantes/génétique , Maladies des plantes/immunologie , Ascomycota/pathogénicité , Résistance à la maladie/génétique , Protéines végétales/génétique , Protéines végétales/métabolisme , Protéines NLR/génétique , Protéines NLR/métabolisme , Aegilops/génétique , Aegilops/microbiologie , Végétaux génétiquement modifiés , Régulation de l'expression des gènes végétaux , Amélioration des plantes , Clonage moléculaire , Gènes de plante
2.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(8): 848-852, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39238409

RÉSUMÉ

OBJECTIVE: To study the biological role and related mechanism of autophagy in acute lung injury (ALI) of hemorrhagic shock mice. METHODS: According to random number table method, wild-type male C57BL/6 mice were divided into control group, ALI group, rapamycin group and 3-methyladenine (3-MA) group, with 8 mice in each group. Light chain 3 (LC3) gene knockout mice with C57BL/6 background were divided into LC3 knockout group and LC3 knockout+ALI group, with 8 mice in each group. Control group, ALI group, LC3 knockout group, LC3 knockout+ALI group were intraperitoneally injected with 2 mL/kg normal saline, rapamycin group was intraperitoneally injected with 3 mg/kg autophagy activator rapamycin, 3-MA group was intraperitoneally injected with 15 mg/kg autophagy inhibitor 3-MA, all of which were given for 3 consecutive days. 2 hours after the last administration, the hemorrhagic shock induced ALI model was established. 24 hours after modeling, the lung index was calculated. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of lung tissue and lung injury score was performed. The expressions of autophagy genes LC3- II/LC3- I and Beclin-1 in lung tissue were detected by Western blotting. The contents of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and malondialdehyde (MDA) in lung tissue were detected according to the steps of the kit. RESULTS: Compared with the control group, the lung tissue structure was destroyed and exudation increased, lung index, lung injury score, the expressions of LC3- II/LC3- I, Beclin-1, and the contents of TNF-α, IL-6 and MDA in lung tissue significantly increased in the ALI group. Compared with the ALI group, the structural damage and exudation of lung tissue were reduced in the rapamycin group, lung index, lung injury score and the contents of TNF-α, IL-6 and MDA in lung tissue decreased, while the expressions of LC3- II/LC3- I and Beclin-1 in lung tissue increased [lung index: (7.56±0.39)% vs. (9.12±0.59)%, lung injury score: 3.04±0.58 vs. 9.32±2.14, TNF-α (ng/mg): 1.85±0.32 vs. 3.51±0.62, IL-6 (ng/mg): 1.61±0.32 vs. 2.52±0.44, MDA (nmol/mg): 1.03±0.16 vs. 1.88±0.24, LC3- II/LC3- I: 1.21±0.12 vs. 0.39±0.05, Beclin-1/ß-actin: 1.10±0.12 vs. 0.58±0.06, all P < 0.05], while lung tissue structure damage was aggravated and exudation was further increased in the 3-MA group, lung index, lung injury score and the contents of TNF-α, IL-6 and MDA in lung tissue increased, the expressions of LC3- II/LC3- I and Beclin-1 in lung tissue decreased [lung index: (10.44±0.62)% vs. (9.12±0.59)%, lung injury score: 11.59±2.28 vs. 9.32±2.14, TNF-α (ng/mg): 4.77±0.71 vs. 3.51±0.62, IL-6 (ng/mg): 3.44±0.52 vs. 2.52±0.44, MDA (nmol/mg): 2.71±0.42 vs. 1.88±0.24, LC3- II/LC3- I: 0.25±0.04 vs. 0.39±0.05, Beclin-1/ß-actin: 0.21±0.03 vs. 0.58±0.06, all P < 0.05]. Lung index, lung injury score and the contents of TNF-α, IL-6 and MDA in lung tissue of LC3 knockout ALI mice were higher than those of wild-type ALI mice [lung index: (10.44±0.75)% vs. (9.12±0.59)%, lung injury score: 12.41±2.86 vs. 9.32±2.14, TNF-α (ng/mg): 4.85±0.72 vs. 3.51±0.62, IL-6 (ng/mg): 3.28±0.51 vs. 2.52±0.44, MDA (nmol/mg): 2.75±0.41 vs. 1.88±0.24, all P < 0.05]. CONCLUSIONS: Autophagy plays a protective role in ALI of hemorrhagic shock mice, and the related molecular mechanism is the inhibition of inflammatory response and oxidative stress response.


Sujet(s)
Lésion pulmonaire aigüe , Autophagie , Interleukine-6 , Souris de lignée C57BL , Souris knockout , Choc hémorragique , Facteur de nécrose tumorale alpha , Animaux , Lésion pulmonaire aigüe/métabolisme , Mâle , Choc hémorragique/métabolisme , Choc hémorragique/complications , Souris , Interleukine-6/métabolisme , Facteur de nécrose tumorale alpha/métabolisme , Modèles animaux de maladie humaine , Poumon/métabolisme , Poumon/anatomopathologie , Protéines associées aux microtubules/métabolisme
3.
Sci China Life Sci ; 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39235557

RÉSUMÉ

Understanding the emergence and spread of antibiotic resistance genes (ARGs) in wildlife is critical for the health of humans and animals from a "One Health" perspective. The gut microbiota serve as a reservoir for ARGs; however, it remains poorly understood how environmental and host genetic factors influence ARGs by affecting the gut microbiota. To elucidate this, we analyzed whole-genome resequencing data from 79 individuals of Brandt's vole in two geographic locations with different antibiotics usage, together with metabolomic data and shotgun sequencing data. A high diversity of ARGs (851 subtypes) was observed in vole's gut, with a large variation in ARG composition between individuals from Xilingol and Hulunbuir in China. The diversity and composition of ARGs were strongly correlated with variations in gut microbiota community structure. Genome-wide association studies revealed that 803 loci were significantly associated (P<5.05×10-9) with 31 bacterial species, and bipartite networks identified 906 bacterial species-ARGs associations. Structural equation modeling analysis showed that host genetic factors, air temperature, and presence of pollutants (Bisphenol A) significantly affected gut microbiota community structure, which eventually regulated the diversity of ARGs. The present study advances our understanding of the complex host-environment interactions that underlie the spread of ARGs in the natural environments.

4.
ACS Appl Mater Interfaces ; 16(37): 49227-49235, 2024 Sep 18.
Article de Anglais | MEDLINE | ID: mdl-39235950

RÉSUMÉ

High-nickel (Ni ≥ 90%) cathodes which have a high specific capacity hold great potential for next-generation lithium-ion batteries (LIBs). However, their practical application is restricted by their high interfacial reactivity because of the presence of residual lithium (Li) compounds on the surface. Herein, the LiNi0.9Co0.06Mn0.04O2 (NCM90) cathode is surface-modified with sulfur (S) via a simple and feasible dry mixing and low-temperature heat treatment, converting the residual lithium compound on the surface into inactive lithium sulfate (Li2SO4). This induces the formation of a stable inorganic enriched electrode-electrolyte interface on the cathode surface and inhibits the occurrence of side reactions, ultimately inhibiting lattice collapse and the dissolution of transition metal ions. After modifying, the capacity retention rates of NCM90/Li and NCM90/graphite cells are both greatly enhanced after long cycling. This work provides a new idea for the rational design of the electrode-electrolyte interface of high-nickel cathodes.

5.
Int J Mol Sci ; 25(18)2024 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-39337596

RÉSUMÉ

Perylenequinones (PQs) are important natural compounds that have been extensively utilized in recent years as agents for antimicrobial, anticancer, and antiviral photodynamic therapies. In this study, we investigated the molecular mechanisms regulating PQ biosynthesis by comparing Shiraia sp. Slf14 with its low PQ titer mutant, Slf14(w). The results indicated that the strain Slf14 exhibited a higher PQ yield, a more vigorous energy metabolism, and a more pronounced oxidation state compared to Slf14(w). Transcriptome analysis consistently revealed that the differences in gene expression between Slf14 and Slf14(w) are primarily associated with genes involved in redox processes and energy metabolism. Additionally, reactive oxygen species (ROS) were shown to play a crucial role in promoting PQ synthesis, as evidenced by the application of ROS-related inhibitors and promoters. Further results demonstrated that mitochondria are significant sources of ROS, which effectively regulate PQ biosynthesis in Shiraia sp. Slf14. In summary, this research revealed a noteworthy finding: the higher energy metabolism of the strain Slf14 is associated with increased intracellular ROS accumulation, which in turn triggers the activation and expression of gene clusters responsible for PQ synthesis.


Sujet(s)
Métabolisme énergétique , Mitochondries , Pérylène , Espèces réactives de l'oxygène , Espèces réactives de l'oxygène/métabolisme , Pérylène/analogues et dérivés , Pérylène/métabolisme , Mitochondries/métabolisme , Quinones/métabolisme , Ascomycota/métabolisme , Ascomycota/génétique , Régulation de l'expression des gènes fongiques , Analyse de profil d'expression de gènes
6.
J Control Release ; 374: 127-139, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39122216

RÉSUMÉ

The immunosuppressive tumor microenvironment (TME) in solid tumors often impedes the efficacy of immunotherapy. Bacterial outer membrane vesicles (OMVs), as a promising cancer vaccine that can potently stimulate immune responses, have garnered interest as a potential platform for cancer therapy. However, the low yield of OMVs limits their utilization. To address this limitation, we developed a novel approach to synthesize OMV-like multifunctional synthetic bacterial vesicles (SBVs) by pretreating bacteria with ampicillin and lysing them through sonication. Compared to OMVs, the yield of SBVs increased by 40 times. Additionally, the unique synthesis process of SBVs allows for the encapsulation of bacterial intracellular contents, endowing SBVs with the capability of delivering catalase (CAT) for tumor hypoxia relief and activating the host cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) signaling pathway. To overcome the toxicity of lipopolysaccharide (LPS) on the SBVs surface, we decorated SBVs with a biocompatible polydopamine (PDA) shell, which allowed TME reprogramming using SBVs to be conducted without adverse side effects. Additionally, the photosensitizer indocyanine green (ICG) was loaded into the PDA shell to induce immunogenic cell death and further improve the efficacy of immunotherapy. In summary, the SBVs-based therapeutic platform SBV@PDA/ICG (SBV@P/I) can synergistically elicit safe and potent tumor-specific antitumor responses through combined immunotherapy and phototherapy.


Sujet(s)
Immunothérapie , Vert indocyanine , Microenvironnement tumoral , Immunothérapie/méthodes , Animaux , Vert indocyanine/administration et posologie , Membrane bactérienne externe , Lignée cellulaire tumorale , Souris de lignée C57BL , Photosensibilisants/administration et posologie , Femelle , Tumeurs/thérapie , Tumeurs/immunologie , Souris , Humains , Catalase/administration et posologie
7.
Inorg Chem ; 63(35): 16233-16242, 2024 Sep 02.
Article de Anglais | MEDLINE | ID: mdl-39161979

RÉSUMÉ

Piezoelectric catalysis could convert mechanical energy into chemical energy, which can combine with solar energy for a high-efficiency piezo-photocatalysis reaction. In this work, NiTiO3 nanorods were synthesized via the sol-gel method and initially employed for the removal of U(VI) from radioactive-contaminated water. The NiTiO3 nanorods will generate an internal electric field in an ultrasonic environment, which could greatly improve the performance of piezo-photocatalysis in reducing U(VI) by promoting the generation of photoexcited electrons and reactive oxygen species (ROS). After exposure to visible light and ultrasound for 3 h, the NTO-R-1 exhibited superb U(VI) degradation efficiency of 93.91%, which was 2.58, 6.15, and 6.68 times greater than those of visible light, ultrasonic irradiation, and dark, respectively. Moreover, photoexcited electrons and oxygen-active species play a decisive role in the piezo-photocatalysis process. Therefore, NiTiO3 with excellent piezo-photocatalysis properties exhibits good potential for the development of efficient wastewater purification catalysts and also helps to probe the possible mechanism of piezo-photocatalysis removal of U(VI) in wastewater.

8.
Poult Sci ; 103(11): 104149, 2024 Nov.
Article de Anglais | MEDLINE | ID: mdl-39154608

RÉSUMÉ

Gyrovirus galga1 (GyVg1), formerly known as AGV2, was initially identified in chickens in southern Brazil. The prevalence of GyVg1 from 2021 to 2024 in 28 out of the 63 poultry farms located in Jiangsu, Anhui, Henan, Hunan, Shandong, and Hubei provinces in eastern and central China was detected via PCR. The complete genomes of the 28 strains were sequenced and exhibited a full length of 2,376 bp. Similarity analysis of these strains did not suggest definite correlation with evolutionary branching and geographical distribution. Compared with the reference GyVg1 strains, HN2202 shared the highest similarity of 99.71% with HLJ1511 (chicken-originated) from northeastern China in 2015 to 2016. Recombination analysis revealed that AH2102 was a potential recombinant of peafowl-originated HN2019-PF1 and chicken-originated HLJ1506-2, whereas HN2304 was a recombinant of peafowl-originated HN2019-PF1 and the Hungarian ferret strain G13. Mutation site analysis of the capsid protein revealed that highly mutated regions occurred between sites 288 to 316 and 383 to 419. These results indicate that GyVg1 may have undergone an interspecies transmission, which involved complex mutations and recombination. This study may provide a reference for subsequent investigations targeting the molecular epidemiology and viral evolution of GyVg1.


Sujet(s)
Poulets , Infections à Circoviridae , Gyrovirus , Maladies de la volaille , Recombinaison génétique , Animaux , Chine/épidémiologie , Maladies de la volaille/virologie , Maladies de la volaille/épidémiologie , Infections à Circoviridae/médecine vétérinaire , Infections à Circoviridae/virologie , Infections à Circoviridae/épidémiologie , Gyrovirus/génétique , Hétérogénéité génétique , Génome viral , Phylogenèse
9.
Nat Immunol ; 25(10): 1858-1870, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39169233

RÉSUMÉ

Cancer cells edit gene expression to evade immunosurveillance. However, genome-wide studies of gene editing during early tumorigenesis are lacking. Here we used single-cell RNA sequencing in a breast cancer genetically engineered mouse model (GEMM) to identify edited genes without bias. Late tumors repressed antitumor immunity genes, reducing infiltrating immune cells and tumor-immune cell communications. Innate immune genes, especially interferon-stimulated genes, dominated the list of downregulated tumor genes, while genes that regulate cell-intrinsic malignancy were mostly unedited. Naive and activated CD8+ T cells in early tumors were replaced with exhausted or precursor-exhausted cells in late tumors. Repression of immune genes was reversed by inhibiting DNA methylation using low-dose decitabine, which suppressed tumor growth and restored immune control, increasing the number, functionality and memory of tumor-infiltrating lymphocytes and reducing the number of myeloid suppressor cells. Decitabine induced important interferon, pyroptosis and necroptosis genes, inflammatory cell death and immune control in GEMM and implanted breast and melanoma tumors.


Sujet(s)
Immunité acquise , Méthylation de l'ADN , Édition de gène , Immunité innée , Animaux , Souris , Femelle , Humains , Décitabine/pharmacologie , Tumeurs du sein/immunologie , Tumeurs du sein/génétique , Lymphocytes T CD8+/immunologie , Régulation de l'expression des gènes tumoraux , Souris de lignée C57BL , Lymphocytes TIL/immunologie , Lymphocytes TIL/métabolisme , Lignée cellulaire tumorale , Souris transgéniques
10.
J Hazard Mater ; 477: 135408, 2024 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-39096641

RÉSUMÉ

This study investigates the spatial and temporal dynamics of air quality in Shandong Province from 2016 to 2022. The Air Quality Index (AQI) showed a seasonal pattern, with higher values in winter due to temperature inversions and heating emissions, and lower values in summer aided by favorable dispersion conditions. The AQI improved significantly, decreasing by approximately 39.4 % from 6.44 to 3.90. Coastal cities exhibited better air quality than inland areas, influenced by industrial activities and geographical features. For instance, Zibo's geography restricts pollutant dispersion, resulting in poor air quality. CO levels remained stable, while O3 increased seasonally due to photochemical reactions in summer, with correlation coefficients indicating a strong positive correlation with temperature (r = 0.65). Winter saw elevated NO2 levels linked to heating and vehicular emissions, with an observed increase in correlation with AQI (r = 0.78). PM2.5 and PM10 concentrations were higher in colder months due to heating and atmospheric dust, showing a significant decrease of 45 % and 40 %, respectively, over the study period. Predictive modeling forecasts continued air quality improvements, contingent on sustained policy enforcement and technological advancements. This approach provides a comprehensive framework for future air quality management and improvement.

11.
ACS Appl Mater Interfaces ; 16(31): 40499-40514, 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-39051468

RÉSUMÉ

Crohn's disease (CD) is a refractory chronic inflammatory bowel disease (IBD) with unknown etiology. Transmural inflammation, involving the intestine and mesentery, represents a characteristic pathological feature of CD and serves as a critical contributor to its intractability. Here, this study describes an oral pyroptosis nanoinhibitor loaded with tumor necrosis factor-α (TNF-α) deoxyribozymes (DNAzymes) (DNAzymes@degradable silicon nanoparticles@Mannose, Dz@MDSN), which can target macrophages at the site of inflammation and respond to reactive oxygen species (ROS) to release drugs. Dz@MDSN can not only break the inflammatory cycle in macrophages by degrading TNF-α mRNA but also reduce the production of ROS mainly from macrophages. Moreover, Dz@MDSN inhibits excessive pyroptosis in epithelial cells through ROS clearance, thereby repairing the intestinal barrier and reducing the translocation of intestinal bacteria to the mesentery. Consequently, these combined actions synergistically contribute to the suppression of inflammation within both the intestine and the mesentery. This study likely represents the first successful attempt in the field of utilizing nanomaterials to achieve transmural healing for CD, which also provides a promising treatment strategy for CD patients.


Sujet(s)
Maladie de Crohn , ADN catalytique , Pyroptose , Facteur de nécrose tumorale alpha , Maladie de Crohn/traitement médicamenteux , Maladie de Crohn/anatomopathologie , Maladie de Crohn/métabolisme , Pyroptose/effets des médicaments et des substances chimiques , Facteur de nécrose tumorale alpha/métabolisme , Humains , Animaux , Administration par voie orale , Souris , ADN catalytique/composition chimique , ADN catalytique/métabolisme , ADN catalytique/pharmacologie , Nanoparticules/composition chimique , Espèces réactives de l'oxygène/métabolisme , Inflammation/traitement médicamenteux , Inflammation/métabolisme , Inflammation/anatomopathologie , Macrophages/effets des médicaments et des substances chimiques , Macrophages/métabolisme , Silicium/composition chimique , Silicium/pharmacologie , Mannose/composition chimique , Mannose/pharmacologie , Cellules RAW 264.7 , Mâle
13.
Ecol Evol ; 14(7): e11500, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39026954

RÉSUMÉ

Many tree species adopt fast seed germination to escape the predation risk by rodents. Physical seed damage and the saliva of rodents on partially consumed seeds may act as cues for seeds to accelerate germination process. However, the impacts of these factors on seed germination rate and speed remain unclear. In this study, we investigated such impacts on the germination rate and speed (reversal of germination time) of four tree species (Quercus variabilis, Q. serrata, Q. acutissima, Q. glauca) after partial consumption by four rodent species (Leopoldamys edwards, Niviventer fulvescens, N. confucianus, Apodemus draco), through a series of experiments. We also examined how seed traits may affect the seed damage degree by rodents by analyzing the relationship between the germination rate and time of rodent-damaged seed and the traits. We found that, artificially- and rodent-damaged seeds exhibited a significantly higher seed germination rate and speed, compared to intact seeds. Also, the rodent saliva on seeds showed no significant effect on seed germination rate and speed. Furthermore, we observed significant positive correlations between several seed traits (including the seed mass, coat thickness, and protein content) and the seed germination rate and speed. These correlations are likely due to their beneficial traits countering seed damage by rodents. Overall, our results highlight the significant role of physical seed damage by rodents (rather than their saliva) in facilitating seed germination of tree species, and potential mutualism between rodents and trees. Additionally, our results may have some implications in forest restoration, such that intentionally sowing or dispersing slightly damaged seeds by humans or drones may increase the likelihood of successful seed regeneration.

14.
Vet J ; 306: 106192, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38964602

RÉSUMÉ

Bufavirus (BuV) was first identified in feces from children with acute diarrhea, and a genetically related Canine bufavirus (CBuV) was first reported in Italy in 2018. In this study, through the investigation of CBuV in 622 anal swabs from dogs with diarrhea symptoms collected from various provinces in northern, central and eastern China during 2018-2022, 14 samples were detected to be positive. And 5 samples were from dogs co-infected with other canine diarrhea related viruses, which consist of CPV-2, CDV and CCoV. The complete genome sequences (4219 nt) of the fourteen strains were amplified and sequenced. Through comparative analysis with 51 reference BuV strains, six strains might recombinate from the CBuV strains (HUN/2012/22, CaBuV/9AS/2005/ITA and CaBuV/35/2016/ITA) in Hungary and Italy as the parents, and two genetic recombination events from various parents were predicted to occur on the BUV-422 strain. Combined analyzing the phylogenetic tree and sequence alignment, it was found that these CBuVs are highly conserved in the nonstructural protein NS1, but indeed various amino acid mutation sites in the capsid protein VP2, and even some amino acid sites coincide with putative protein plastic regions and potential epitopes. The BUV-422 and BUV-512 strains show sequential mutation sites identical to the divergent strains of CaBuV/9AS/2005/ITA and CaBuV/35/2016/ITA. This study would enrich the molecular data of CBuV in China and provide essential reference for the epidemiological research and vaccine development of CBuV in the future.


Sujet(s)
Diarrhée , Maladies des chiens , Infections à Parvoviridae , Phylogenèse , Recombinaison génétique , Animaux , Chiens , Maladies des chiens/virologie , Maladies des chiens/épidémiologie , Chine/épidémiologie , Diarrhée/médecine vétérinaire , Diarrhée/virologie , Diarrhée/épidémiologie , Infections à Parvoviridae/médecine vétérinaire , Infections à Parvoviridae/virologie , Infections à Parvoviridae/épidémiologie , Génome viral
15.
Nat Nanotechnol ; 19(7): 907-918, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38987649

RÉSUMÉ

The exceptional physical properties of two-dimensional (2D) van der Waals (vdW) materials have been extensively researched, driving advances in material synthesis. Epitaxial growth, a prominent synthesis strategy, enables the production of large-area, high-quality 2D films compatible with advanced integrated circuits. Typical 2D single crystals, such as graphene, transition metal dichalcogenides and hexagonal boron nitride, have been epitaxially grown at a wafer scale. A systematic summary is required to offer strategic guidance for the epitaxy of emerging 2D materials. Here we focus on the epitaxy methodologies for 2D vdW materials in two directions: the growth of in-plane single-crystal monolayers and the fabrication of out-of-plane homostructures. We first discuss nucleation control of a single domain and orientation control over multiple domains to achieve large-scale single-crystal monolayers. We analyse the defect levels and measures of crystalline quality of typical 2D vdW materials with various epitaxial growth techniques. We then outline technical routes for the growth of homogeneous multilayers and twisted homostructures. We further summarize the current strategies to guide future efforts in optimizing on-demand fabrication of 2D vdW materials, as well as subsequent device manufacturing for their industrial applications.

16.
Ecotoxicol Environ Saf ; 281: 116668, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38964058

RÉSUMÉ

The study of the fractions and distribution characteristics of organic phosphorus in the sediment of the water level fluctuating zone of Nansi Lake is conducive to revealing the transformation of phosphorus in the lake, and has important scientific significance for controlling the eutrophication of Nansi Lake. Based on the sediment of the water level fluctuation zone of Nansi Lake. The improved Hedley continuous grading extraction, ultraviolet-visible spectroscopy and three-dimensional fluorescence spectroscope were used to characterize the structural characteristics and stability of organic molecules in the sediment, and to reflect the differences in the structure and stability of organophosphate in the water level fluctuating zone. Principal component analysis (PCA), Redundancy analysis (RDA) and correlation heat map analysis were used to analyze the correlation between phosphorus and physicochemical index. The results showed that the alternation between wet-dry conditions was more favorable for the release of phosphorus from sediment, compared to continuous inundation conditions. Moreover, the higher the frequency of wet-dry alternations, the greater the release of phosphorus in different forms from the sediment. Wet-dry alternation resulted in a reduction of substituent on the aromatic rings of sediment DOM (dissolved organic matter), and the continuous drying would increase the molecular weight and humidification degree of DOM in the sediment. Correlation analysis showed that NaOH-Po content in sediment was significantly negatively correlated with TP, IP, OP and various organophosphorus forms, indicating a close transformation relationship between phosphorus forms in sediment. The results can provide a scientific basis for controlling the release of endogenous phosphorus and the risk of eutrophication in Nansi Lake.


Sujet(s)
Surveillance de l'environnement , Eutrophisation , Sédiments géologiques , Lacs , Phosphore , Polluants chimiques de l'eau , Sédiments géologiques/composition chimique , Lacs/composition chimique , Phosphore/analyse , Phosphore/composition chimique , Polluants chimiques de l'eau/analyse , Chine , Analyse en composantes principales
17.
Plant J ; 119(3): 1543-1557, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38859560

RÉSUMÉ

Aegilops longissima and Ae. sharonensis, being classified into the Sitopsis section of genus Aegilops, are distinct species both taxonomically and ecologically. Nevertheless, earlier observations indicate that the two species are not reproductively isolated to full extent and can inter-bred upon secondary contact. However, the genomic underpinnings of the morpho-ecological differentiation between the two foci species remained unexplored. Here, we resequenced 31 representative accessions of the two species and conducted in-depth comparative genomic analyses. We demonstrate recurrent and ongoing natural hybridizations between Ae. longissima and Ae. sharonensis, and depict features of genome composition of the resultant hybrids at both individual and population levels. We also delineate genomic regions and candidate genes potentially underpinning the differential morphological and edaphic adaptations of the two species. Intriguingly, a binary morphology was observed in the hybrids, suggesting existence of highly diverged genomic regions that remain uneroded by the admixtures. Together, our results provide new insights into the molding effects of interspecific hybridization on genome composition and mechanisms preventing merge of the two species.


Sujet(s)
Aegilops , Diploïdie , Génome végétal , Hybridation génétique , Génome végétal/génétique , Aegilops/génétique , Génomique , Évolution moléculaire , Phylogenèse
18.
Nat Commun ; 15(1): 4796, 2024 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-38839783

RÉSUMÉ

Powdery mildew is a devastating disease that affects wheat yield and quality. Wheat wild relatives represent valuable sources of disease resistance genes. Cloning and characterization of these genes will facilitate their incorporation into wheat breeding programs. Here, we report the cloning of Pm57, a wheat powdery mildew resistance gene from Aegilops searsii. It encodes a tandem kinase protein with putative kinase-pseudokinase domains followed by a von Willebrand factor A domain (WTK-vWA), being ortholog of Lr9 that mediates wheat leaf rust resistance. The resistance function of Pm57 is validated via independent mutants, gene silencing, and transgenic assays. Stable Pm57 transgenic wheat lines and introgression lines exhibit high levels of all-stage resistance to diverse isolates of the Bgt fungus, and no negative impacts on agronomic parameters are observed in our experimental set-up. Our findings highlight the emerging role of kinase fusion proteins in plant disease resistance and provide a valuable gene for wheat breeding.


Sujet(s)
Aegilops , Ascomycota , Résistance à la maladie , Maladies des plantes , Protéines végétales , Végétaux génétiquement modifiés , Triticum , Triticum/microbiologie , Triticum/génétique , Résistance à la maladie/génétique , Maladies des plantes/microbiologie , Maladies des plantes/génétique , Maladies des plantes/immunologie , Ascomycota/génétique , Ascomycota/pathogénicité , Protéines végétales/génétique , Protéines végétales/métabolisme , Aegilops/génétique , Aegilops/microbiologie , Amélioration des plantes , Protein kinases/génétique , Protein kinases/métabolisme , Clonage moléculaire , Régulation de l'expression des gènes végétaux
19.
Nature ; 629(8010): 74-79, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38693415

RÉSUMÉ

Within the family of two-dimensional dielectrics, rhombohedral boron nitride (rBN) is considerably promising owing to having not only the superior properties of hexagonal boron nitride1-4-including low permittivity and dissipation, strong electrical insulation, good chemical stability, high thermal conductivity and atomic flatness without dangling bonds-but also useful optical nonlinearity and interfacial ferroelectricity originating from the broken in-plane and out-of-plane centrosymmetry5-23. However, the preparation of large-sized single-crystal rBN layers remains a challenge24-26, owing to the requisite unprecedented growth controls to coordinate the lattice orientation of each layer and the sliding vector of every interface. Here we report a facile methodology using bevel-edge epitaxy to prepare centimetre-sized single-crystal rBN layers with exact interlayer ABC stacking on a vicinal nickel surface. We realized successful accurate fabrication over a single-crystal nickel substrate with bunched step edges of the terrace facet (100) at the bevel facet (110), which simultaneously guided the consistent boron-nitrogen bond orientation in each BN layer and the rhombohedral stacking of BN layers via nucleation near each bevel facet. The pure rhombohedral phase of the as-grown BN layers was verified, and consequently showed robust, homogeneous and switchable ferroelectricity with a high Curie temperature. Our work provides an effective route for accurate stacking-controlled growth of single-crystal two-dimensional layers and presents a foundation for applicable multifunctional devices based on stacked two-dimensional materials.

20.
PLoS One ; 19(5): e0301788, 2024.
Article de Anglais | MEDLINE | ID: mdl-38696421

RÉSUMÉ

With an increasing number of heterogeneous shareholders participating in corporate governance in reality, the assumption of shareholder homogeneity in agency theory is gradually relaxing in the modern field of corporate governance. The policy of mixed ownership reform in China provides empirical evidence for studying heterogeneous shareholder governance. To fully understand the governance effects of non-state shareholders, we employ the ownership proportion held by non-state shareholders among the top ten shareholders and the appointment of directors as measures for non-state shareholder governance. Using a panel fixed-effect model from the perspective of state-owned enterprises (SOEs) party organizations, we examine the impact of non-state shareholder governance on the governance level of SOEs. The study reveals that non-state shareholder governance positively affects the governance level of SOEs, with board resolutions playing a crucial role in this relationship. When party members serve as directors, the governance effect of non-state shareholders is more significant. Based on the aforementioned research findings, we recommend further refining corporate governance measures for SOEs within the context of SOE reforms. It is advisable to optimize the party organizational governance structure and leverage the synergistic effects of non-state shareholder governance and party organizational governance. Advancing reforms along the Pareto improvement path will contribute to establishing a distinctive corporate governance system for Chinese SOEs.


Sujet(s)
Conseil administration , Propriété , Chine , Conseil administration/organisation et administration , Humains , Gouvernement d'un État
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