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1.
Proc Natl Acad Sci U S A ; 120(19): e2219098120, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37126725

RESUMO

Graphene oxide (GO) membranes with nanoconfined interlayer channels theoretically enable anomalous nanofluid transport for ultrahigh filtration performance. However, it is still a significant challenge for current GO laminar membranes to achieve ultrafast water permeation and high ion rejection simultaneously, because of the contradictory effect that exists between the water-membrane hydrogen-bond interaction and the ion-membrane electrostatic interaction. Here, we report a vertically aligned reduced GO (VARGO) membrane and propose an electropolarization strategy for regulating the interfacial hydrogen-bond and electrostatic interactions to concurrently enhance water permeation and ion rejection. The membrane with an electro-assistance of 2.5 V exhibited an ultrahigh water permeance of 684.9 L m-2 h-1 bar-1, which is 1-2 orders of magnitude higher than those of reported GO-based laminar membranes. Meanwhile, the rejection rate of the membrane for NaCl was as high as 88.7%, outperforming most reported graphene-based membranes (typically 10 to 50%). Molecular dynamics simulations and density-function theory calculations revealed that the electropolarized VARGO nanochannels induced the well-ordered arrangement of nanoconfined water molecules, increasing the water transport efficiency, and thereby resulting in improved water permeation. Moreover, the electropolarization effect enhanced the surface electron density of the VARGO nanochannels and reinforced the interfacial attractive interactions between the cations in water and the oxygen groups and π-electrons on the VARGO surface, strengthening the ion-partitioning and Donnan effect for the electrostatic exclusion of ions. This finding offers an electroregulation strategy for membranes to achieve both high water permeability and high ion rejection performance.

2.
Plant Biotechnol J ; 22(11): 3085-3098, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39037027

RESUMO

As an essential macronutrient, phosphorus (P) is often a limiting nutrient because of its low availability and mobility in soils. Drought is a major environmental stress that reduces crop yield. How plants balance and combine P-starvation responses (PSRs) and drought resistance is unclear. In this study, we identified the transcription factor ZmPHR1 as a major regulator of PSRs that modulates phosphate (Pi) signaling and homeostasis. We found that maize zmphr1 mutants had reduced P concentration and were sensitive to Pi starvation, whereas ZmPHR1-OE lines displayed elevated Pi concentration and yields. In addition, 57% of PSR genes and nearly 70% of ZmPHR1-regulated PSR genes in leaves were transcriptionally responsive to drought. Under moderate and early drought conditions, the Pi concentration of maize decreased, and PSR genes were up-regulated before drought-responsive genes. The ZmPHR1-OE lines exhibited drought-resistant phenotypes and reduced stomatal apertures, whereas the opposite was true of the zmphr1 mutants. ZmPT7-OE lines and zmspx3 mutants, which had elevated Pi concentration, also exhibited drought resistance, but zmpt7 mutants were sensitive to drought. Our results suggest that ZmPHR1 plays a central role in integrating Pi and drought signals and that Pi homeostasis improves the ability of maize to combat drought.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Homeostase , Fosfatos , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/fisiologia , Fosfatos/metabolismo , Fosfatos/deficiência , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Mutação , Estresse Fisiológico/genética , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Resistência à Seca
3.
Yeast ; 40(11): 540-549, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37818980

RESUMO

Five yeast strains isolated from tree bark and rotten wood collected in central and southwestern China, together with four Brazilian strains (three from soil and rotting wood collected in an Amazonian rainforest biome and one from Bromeliad collected in Alagoas state) and one Costa Rican strain isolated from a flower beetle, represent a new species closely related with Yueomyces sinensis in Saccharomycetaceae, as revealed by the 26S ribosomal RNA gene D1/D2 domain and the internal transcribed spacer region sequence analysis. The name Yueomyces silvicola sp. nov. is proposed for this new species with the holotype China General Microbiological Culture Collection Center 2.6469 (= Japan Collection of Microorganisms 34885). The new species exhibits a whole-genome average nucleotide identity value of 77.8% with Y. sinensis. The two Yueomyces species shared unique physiological characteristics of being unable to utilize ammonium and the majority of the amino acids, including glutamate and glutamine, as sole nitrogen sources. Among the 20 amino acids tested, only leucine and tyrosine can be utilized by the Yueomyces species. Genome sequence comparison showed that GAT1, which encodes a GATA family protein participating in transcriptional activation of nitrogen-catabolic genes in Saccharomyces cerevisiae, is absent in the Yueomyces species. However, the failure of the Yueomyces species to utilize ammonium, glutamate, and glutamine, which are generally preferred nitrogen sources for microorganisms, implies that more complicated alterations in the central nitrogen metabolism pathway might occur in the genus Yueomyces.


Assuntos
Compostos de Amônio , Saccharomycetales , Saccharomyces cerevisiae/genética , Glutamina/genética , Ácido Glutâmico/genética , Filogenia , DNA Espaçador Ribossômico/genética , Análise de Sequência de DNA , Saccharomycetales/genética , Aminoácidos/genética , DNA Fúngico/genética
4.
Mol Biol Rep ; 41(8): 5247-56, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24842264

RESUMO

The NPR1 gene was an important regulator for a plant disease resistance. The cDNA of NPR1 gene was cloned from peanut cultivar Ri Hua 1 by rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The full length cDNA of Arachis hypogaea NPR1 consisted of 2,078 base pairs with a 1,446 bp open-reading frame encoding 481 amino acids. The predicted NPR1 contained the highly conserved functional domains (BTB/POZ domain from M1 to D116), protein-protein interaction domains (three ankyrin repeats from K158 to L186; N187 to L217 and R221 to D250) and one NPR1-like domain (C262 to S469). The DNA sequence of the NPR1 gene was 2,332 or 2,223 bp. Both two sequences contained three introns and four exons. The NPR1 transcripts were expressed mainly in roots and leaves, while fewer signals were detected in the stems. Amount of the NPR1 transcript was significantly increased 1 h after salicylic acid challenge and was eventually 5.3 times greater than that in the control group. Both the DNA sequence and the coding sequence were obtained from eight cultivars and nine wild species of Arachis. Maximum likelihood analyses of d N/d S ratios for 25 sequences from different species showed that different selection pressures may have acted on different branches.


Assuntos
Arachis/genética , Regulação da Expressão Gênica de Plantas , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Receptores do Fator Natriurético Atrial/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA de Plantas/genética , Éxons , Íntrons , Dados de Sequência Molecular , Filogenia , Doenças das Plantas/genética , Proteínas de Plantas/metabolismo , Domínios e Motivos de Interação entre Proteínas , Ácido Salicílico/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA
5.
IEEE Trans Image Process ; 33: 3456-3469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787666

RESUMO

Our work focuses on tackling the problem of fine-grained recognition with incomplete multi-modal data, which is overlooked by previous work in the literature. It is desirable to not only capture fine-grained patterns of objects but also alleviate the challenges of missing modalities for such a practical problem. In this paper, we propose to leverage a meta-learning strategy to learn model abilities of both fast modal adaptation and more importantly missing modality completion across a variety of incomplete multi-modality learning tasks. Based on that, we develop a meta-completion method, termed as MECOM, to perform multimodal fusion and explicit missing modality completion by our proposals of cross-modal attention and decoupling reconstruction. To further improve fine-grained recognition accuracy, an additional partial stream (as a counterpart of the main stream of MECOM, i.e., holistic) and the part-level features (corresponding to fine-grained objects' parts) selection are designed, which are tailored for fine-grained nature to capture discriminative but subtle part-level patterns. Comprehensive experiments from quantitative and qualitative aspects, as well as various ablation studies, on two fine-grained multimodal datasets and one generic multimodal dataset show our superiority over competing methods. Our code is open-source and available at https://github.com/SEU-VIPGroup/MECOM.

7.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 15(10): 628-30, 2003 Oct.
Artigo em Zh | MEDLINE | ID: mdl-14552691

RESUMO

OBJECTIVE: To determine hypotonic liquid containing colloid on hemorrhagic dogs with celiac seawater immersion wound. METHODS: Thirty-five dogs were randomly divided into five groups: control group (group A), 0.9% NaCl therapy group (group B) and 0.45% NaCl therapy group (group C), 5% glucose therapy group(group D) and hypotonic liquid containing colloid therapy group (group E). Changes of mean artery pressure (MAP), cardiac output (CO), urine volume, plasma osmotic pressure and pathologic changes of lung and brain were observed. RESULTS: hypotonic liquid containing colloid could effectively ameliorate MAP and CO, improve urine volume, decrease plasma osmotic pressure and prevent occurrence of lung and brain edema. CONCLUSION: Hypotonic liquid containing colloid can exert satisfactory therapeutic effects on hemorrhagic dogs with celiac seawater immersion wound.


Assuntos
Soluções Hipotônicas/uso terapêutico , Água do Mar/efeitos adversos , Choque Hemorrágico/terapia , Animais , Pressão Sanguínea , Débito Cardíaco , Coloides , Cães , Imersão , Pressão Osmótica , Choque Hemorrágico/patologia
8.
Bing Du Xue Bao ; 25(5): 355-61, 2009 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19954112

RESUMO

Pigeon circovrius (PiCV) is a member of circovirus, which is usually regarded as an immunosuppression agent. There were reports that pigeons infected by PiCV showed symptoms of lethargy, weight loss, vomiting, diarrhea, respiratory distress, etc. In this study, we established a PCR method for the detection of PiCV DNA. Samples from 5 different farms in Zhejiang Province were examined and samples from a farm in Hangzhou were positive. Furthermore, the genomic segments of 2 strains of PiCV were amplified, cloned and sequenced using designed primers and the complete genomes of the strains were then assembled and named as PiCV-zj1 and PiCV-zj2, respectively. The sequences were deposited in GenBank under the GenBank Accession number of DQ090945 and DQ090944, respectively. Sequence Analysis had shown that the complete genomes of 2 strains of PiCV from Zhejiang Province had 2 039 nucleotides totally in length and common characters of circovirus such as a stem-loop structure and conserved motifs for Rep protein, which were supposed to be related to the replication of the virus. Pairwise comparisons showed that the nucleotide sequence of the genome of PiCV strains from Zhejiang Province had 86%-89.1% identities to that of 11 published PiCV strains, and that the amino acid identities of the replication-associated protein (Rep) and capsid protein (Cap) displayed 92.1%-94.7% and 76.6%-81.4%, respectively. A phylogenic tree was built using PHYLIP with bootstrap support for 1 000 replicates. The result showed that 10 strains from Europe and America formed one big branch and the others from Zhejiang Province and Australia formed the other two, respectively. This was the first report on the detection and full genome sequencing of PiCV in China.


Assuntos
Infecções por Circoviridae/virologia , Circovirus/genética , Columbidae/virologia , Genoma Viral/genética , Animais , Sequência de Bases , Circovirus/classificação , Clonagem Molecular , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Proteínas Virais/genética
9.
Electron. j. biotechnol ; Electron. j. biotechnol;15(5): 1-1, Sept. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-657660

RESUMO

Background: Bacterial wilt caused by Ralstonia solanacearum is the most devastating disease in peanut. Planting resistant peanut cultivars is deemed as the sole economically viable means for effective control of the disease. To understand the molecular mechanism underlying resistance and facilitate breeding process, differences in gene expression between seeds of Rihua 1 (a Virginia type peanut variety resistant to bacterial wilt) inoculated with the bacterial pathogen suspension (10(9) cfu ml-1) and seeds of the same cultivar treated with water (control), were studied using the GenefishingTM technology. Results: A total of 25 differentially expressed genes were isolated. Expression of genes encoding cyclophilin and ADP-ribosylation factor, respectively, were further studied by real time RT-PCR, and full length cDNAs of both genes were obtained by rapid amplification of cDNA ends. Conclusions: The study provided candidate genes potentially useful for breeding peanut cultivars with both high yield and bacterial wilt resistance, although confirmation of their functions through transgenic studies is still needed.


Assuntos
Arachis/genética , Fatores de Ribosilação do ADP/genética , Ralstonia solanacearum/patogenicidade , Imunidade Inata , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência
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