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Olivine LiFePO4 covered flocculent carbon layers wrapped with carbon nanotubes (CNTs) prepared by sol-gel method and calcination is used as the cathode material for aqueous rechargeable lithium-ion batteries (ARLBs). The phase structures and morphologies of the composite material are characterized by X-ray diffraction (XRD), selected area electron diffraction (SAED), and transmission electron microscopy (TEM). The mechanism and method through which CNTs and flocculent carbon improve the electrochemical performance are investigated in an aqueous lithium-ion battery by setting up a comparative experiment. The ARLB system is assembled using a LiFePO4/C/CNTs cathode and a zinc anode in 1 mol L-1 ZnSO4·7H2O and saturated LiNO3 aqueous solution (pH = 6), which can deliver a capacity of 158 mA h g-1 at a rate of 1C. Even at a rate of 50C, it still has a capacity of 110 mA h g-1 after 250 cycles with fantastic capacity retention (95.7%). The lithium-ion diffusion coefficient increases by an order of magnitude due to the addition of CNTs together with flocculent carbon. Four LEDs are successfully powered by the ARLBs for more than one minute to demonstrate the practical application. The excellent rate capabilities and thrilling discharge capacity at a high rate indicate that this cathode material possesses excellent electrochemical performance, and this ARLB system exhibits excellent potential as a power source for environmental applications.
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BACKGROUND: Tbx2 plays a critical role in determining fates of cardiomyocytes. Little is known about the contribution of TBX2 3' untranslated region (UTR) variants to the risk of congenital heart defect (CHD). Thus, we aimed to determine the association of single-nucleotide polymorphisms (SNPs) in TBX2 3' UTR with CHD susceptibility. METHODS: We recruited 1285 controls and 1241 CHD children from China. SNPs identification and genotyping were detected using Sanger Sequencing and SNaPshot. Stratified analysis was conducted to explore the association between rs59382073 polymorphism and CHD subtypes. Functional analyses were performed by luciferase assays in HEK-293T and H9c2 cells. RESULTS: Among five TBX2 3'UTR variants identified, rs59382073 minor allele T carriers had a 1.89-fold increased CHD risk compared to GG genotype (95% CI = 1.48-2.46, P = 4.48 × 10-7). The most probable subtypes were right ventricular outflow tract obstruction, conotruncal, and septal defect. G to T variation decreased luciferase activity in cells. This discrepancy was exaggerated by miR-3940 and miR-708, while their corresponding inhibitors eliminated it. CONCLUSION: T allele of rs59382073 in TBX2 3'UTR contributed to greater CHD risk in the Han Chinese population. G to T variation created binding sites for miR-3940 and miR-708 to inhibit gene expression.
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Predisposição Genética para Doença , Cardiopatias Congênitas/genética , Polimorfismo de Nucleotídeo Único , Proteínas com Domínio T/genética , Regiões 3' não Traduzidas , Alelos , Animais , Povo Asiático , Sítios de Ligação , Estudos de Casos e Controles , Criança , China/etnologia , Ecocardiografia , Feminino , Regulação da Expressão Gênica , Genótipo , Células HEK293 , Cardiopatias Congênitas/etnologia , Ventrículos do Coração , Humanos , Masculino , MicroRNAs/genética , Fenótipo , Plasmídeos/metabolismo , Ratos , Medição de RiscoRESUMO
BACKGROUND: Folate deficiency is an independent risk factor for congenital heart disease (CHD); however, the maternal plasma folate level is paradoxically not a good diagnostic marker. Genome-wide surveys have identified variants of nonfolate metabolic genes associated with the plasma folate level, suggesting that these genetic polymorphisms are potential risk factors for CHD. METHODS: To examine the effects of folate concentration-related variations on CHD risk in the Han Chinese population, we performed 3 independent case-control studies including a total of 1489 patients with CHD and 1745 control subjects. The expression of the Fidgetin (FIGN) was detected in human cardiovascular and decidua tissue specimens with quantitative real-time polymerase chain reaction and Western blotting. The molecular mechanisms were investigated by luciferase reporter assays, surface plasmon resonance, and chromatin immunoprecipitation. FIGN-interacting proteins were confirmed by tandem affinity purification and coimmunoprecipitation. Proteasome activity and metabolite concentrations in the folate pathway were quantified with a commercial proteasome activity assay and immunoassays, respectively. RESULTS: The +94762G>C (rs2119289) variant in intron 4 of the FIGN gene was associated with significant reduction in CHD susceptibility (P=5.1×10-14 for the allele, P=8.5×10--13 for the genotype). Analysis of combined samples indicated that CHD risks in individuals carrying heterozygous (GC) or homozygous (CC) genotypes were reduced by 44% (odds ratio [OR]=0.56; 95% confidence interval [CI]=0.47-0.67) and 66% (OR=0.34; 95% CI=0.23-0.50), respectively, compared with those with the major GG genotype. Minor C allele carriers who had decreased plasma folate levels exhibited significantly increased FIGN expression because the transcription suppressor CREB1 did not bind the alternative promoter of FIGN isoform X3. Mechanistically, increased FIGN expression led to the accumulation of both reduced folate carrier 1 and dihydrofolate reductase via inhibition of their proteasomal degradation, which promoted folate absorption and metabolism. CONCLUSIONS: We report a previously undocumented finding that decreased circulating folate levels induced by increased folate transmembrane transport and utilization, as determined by the FIGN intronic variant, serves as a protective mechanism against CHD. Our results may explain why circulating folate levels do not have a good diagnostic value.
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Adenosina Trifosfatases/genética , Povo Asiático/genética , Ácido Fólico/sangue , Cardiopatias Congênitas/prevenção & controle , Íntrons , Polimorfismo de Nucleotídeo Único , ATPases Associadas a Diversas Atividades Celulares , Adenosina Trifosfatases/metabolismo , Animais , Biomarcadores/sangue , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Pré-Escolar , China/epidemiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação para Baixo , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Células HEK293 , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/etnologia , Cardiopatias Congênitas/genética , Heterozigoto , Homozigoto , Humanos , Modelos Logísticos , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas aos Microtúbulos , Razão de Chances , Fenótipo , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Proteção , Proteólise , Interferência de RNA , Ratos , Medição de Risco , Fatores de Risco , Tetra-Hidrofolato Desidrogenase/metabolismo , Transcrição Gênica , TransfecçãoRESUMO
OBJECTIVE: To detect VHL gene mutation in a pedigree affected with von Hippel-Lindau syndrome (VHL). METHODS: Clinical data of the pedigree was reviewed. Patients were subjected to Sanger sequencing to detect mutation of the VHL gene. Structure of pVHL was predicted by 3D modeling using the swiss-model. RESULTS: A novel c.426delT(p.V142fs) [NM_000551] mutation was found in exon 2 of the VHL gene. 3D modeling suggested that the alpha-structure of pVHL is completely absent. CONCLUSION: The novel c.426delT(p.V142fs) mutation probably underlies the VHL in this pedigree.
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Proteína Supressora de Tumor Von Hippel-Lindau/genética , Doença de von Hippel-Lindau/genética , Análise Mutacional de DNA , Éxons , Humanos , Mutação , LinhagemRESUMO
AIMS: Elevated homocysteine levels are known to be a risk factor for congenital heart disease (CHD), but the mechanism underlying this effect is unknown. During early embryonic development, homocysteine removal is dictated exclusively by the MTR activity. To examine the role of MTR in CHD risk, we identified genetic variants in MTR and investigated the mechanisms that affect its expression levels and that increase the risk of CHD in Chinese populations. METHODS AND RESULTS: The association between regulatory variants of the MTR gene and CHD was examined in three independent case-control studies in a total of 2340 patients with CHD and 2270 controls. The functional consequences of these variants were demonstrated using dual-luciferase assays, real-time polymerase chain reaction (PCR), electrophoretic mobility shift assays, surface plasma resonance, chromatin immunoprecipitation, and bisulfite sequencing, as well as by a group of predicted microRNAs using a gene reporter system. Two regulatory variants of MTR, -186T>G and +905G>A, were associated with an increased risk of CHD in both the separate and combined case-control studies (-186GG P = 1.32 × 10(-9); +905AA P = 6.35 × 10(-14)). Compared with the major allele, the -186G allele exhibited significantly lower promoter activity, decreased hnRNA and mRNA levels, reduced transcription factor binding affinity, and a more highly methylated promoter. The +905A allele exhibited a statistically stronger binding affinity to functional microRNAs that down regulate MTR expression at the translational level. Both of the minor alleles were correlated with elevated plasma homocysteine concentrations, indicating a genetic component for hyperhomocysteinaemia. CONCLUSIONS: Regulatory variants of the MTR gene increase CHD risk by reducing MTR expression and inducing the homocysteine accumulation and elevation.
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5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Cardiopatias Congênitas/genética , Povo Asiático/genética , Estudos de Casos e Controles , Metilação de DNA/genética , Ferredoxina-NADP Redutase/genética , Expressão Gênica/genética , Predisposição Genética para Doença/genética , Genótipo , Homocisteína/metabolismo , Humanos , Hiper-Homocisteinemia/genética , MicroRNAs/genética , Fatores de Risco , Transcrição Gênica/genéticaRESUMO
To assess the effect of the NFKB1 -94ins/del polymorphism on cancer, we conducted a meta-analysis based on 25 studies including 8,750 cases and 9,170 controls. Overall, the -94ins/del polymorphism was associated with cancer risk in the pooled analysis and in Asian population, whereas no association was observed in Caucasian population. Stratified analysis by subtypes of cancer showed that the -94ins/del polymorphism was associated with oral squamous cell carcinoma and ovarian cancer risk, but had no association with colorectal cancer, bladder cancer, and renal cell cancer. Our meta-analysis suggests the NFKB1 -94ins/del polymorphism affects cancer susceptibility, and the association is ethnic-specific.
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Predisposição Genética para Doença , Mutação INDEL/genética , Subunidade p50 de NF-kappa B/genética , Neoplasias/genética , Neoplasias Ovarianas/genética , Povo Asiático/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Escamosas/genética , Neoplasias Colorretais/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Neoplasias Renais/genética , Neoplasias Bucais/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Risco , Neoplasias da Bexiga Urinária/genética , População Branca/genéticaRESUMO
As a well-known transcription factor, TBX5 is involved in embryonic cardiac development. Although TBX5 functions in a dose-dependent manner, the posttranscriptional regulation of human TBX5 is poorly understood. Thus, this study aimed to identify microRNAs that modulate TBX5 expression. Luciferase assays were used to screen miRNAs predicted to modulate TBX5 expression. Using quantitative reverse transcriptase-polymerase chain reaction and Western blot analysis, the authors found that miR-10a and miR-10b significantly repressed TBX5 expression and decreased TBX5 protein levels by targeting the TBX5 3'-untranslated region. In addition, miR-10a and miR-10b expression levels were respectively 2.77 and 3.51 times higher in the heart tissues of congenital heart disease patients than in healthy control subjects, suggesting that they are potential diagnostic biomarkers. In conclusion, the study results indicate that miR-10a and miR-10b inhibit TBX5 expression at the level of translation. Higher levels of miR-10a and miR-10b expression are associated with a higher risk of congenital heart defects.
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Cardiopatias Congênitas/genética , MicroRNAs/genética , Proteínas com Domínio T , Regiões 3' não Traduzidas , China , Feminino , Regulação da Expressão Gênica , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Masculino , Processamento de Proteína Pós-Traducional , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismoRESUMO
INTRODUCTION: Hepatolenticular degeneration (Wilson disease) is an autosomal recessive monogenic disorder caused by mutations in the ATPase copper transporting beta (ATP7B) gene located on human chromosome 13. This gene encodes a copper-transporting P-type ATPase (ATP7B). Recent studies have revealed that the ATP7B gene is predominantly affected by a few hotspot mutations, with the His1069Gln mutation in exon 14 accounting for 50 to 80% of cases. In China, the Arg778Leu mutation in exon 8 is the most prevalent. However, the discovery of novel mutant genes persists. CASE PRESENTATION: A 56-year-old Chinese female was referred to our hospital with a liver injury and cirrhosis. Her parents, 2 younger brothers, and children exhibited no signs of liver function impairment. Whole-exome sequencing was conducted on the proband's genomic DNA, and Sanger sequencing was performed on 6 family members for first-generation verification. CONCLUSIONS: We identified a novel c.3715Gâ >â T (p.Val1239Phe) variant mutation in the ATP7B gene in the patient. The ATP7B c.3715Gâ >â T (p.Val1239Phe) variant is predicted to impact the copper transport P-type ATPase. When combined with another mutant gene to form a compound heterozygous mutation, it can lead to hepatolenticular degeneration. This discovery broadens the range of pathogenic genes in the ATP7B gene.
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ATPases Transportadoras de Cobre , Degeneração Hepatolenticular , Humanos , Degeneração Hepatolenticular/genética , ATPases Transportadoras de Cobre/genética , Feminino , Pessoa de Meia-Idade , Mutação , China , Linhagem , População do Leste AsiáticoRESUMO
Inositol 1,4,5-Trisphosphate Receptor-Interacting Protein-Like 1 (ITPRIPL1), a single-pass type I membrane protein located in the membrane, functions as an inhibitory ligand of CD3ε. Recent studies have shown that its expression suppresses T cells activation and promote tumor immune evasion. Despite increasing evidence suggesting that ITPRIPL1 plays a significant role in tumor growth, no systematic pan-cancer analysis of ITPRIPL1 has been conducted to date. This study utilized datasets curated from The Cancer Genome Atlas, Genotype Tissue-Expression, and Human Protein Atlas to investigate the relationship between ITPRIPL1 expression and clinical outcomes, immune infiltration, and drug sensitivity across 33 cancer types. We employed multiple methods to assess its prognostic value in pan-cancer, such as univariate Cox regression, survival analysis, and ROC curve analysis and explored the relationship between ITPRIPL1 and tumor mutation burden (TMB), tumor microsatellite instability (MSI), CNV, DNA methylation, immune-related genes, immune cell infiltration, and drug sensitivity to reveal its immunological role. The mRNA expression levels of the ITPRIPL1 gene vary significantly across multiple types of cancer and significantly reduced in breast cancer. Conversely, high ITPRIPL1 expression was associated with a better prognosis in BRCA. Furthermore, the expression of ITPRIPL1 highly correlates with the presence of tumor-infiltrating immune cells and immune checkpoint genes across various types of cancers. Additionally, ITPRIPL1 expression was associated with TMB in 6 cancer types and with MSI in 13 cancer types. High expression of ITPRIPL1 serves as a protective factor in certain cancer types, correlating with longer overall survival in BRCA. Our study further confirms that ITPRIPL1 participates in regulating immune infiltration and affecting the prognosis of patients in pan-cancer. These findings underscore the promising potential of ITPRIPL1 as a therapeutic target for human cancer.
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BACKGROUND: Homocysteine is known to be an independent risk factor for congenital heart disease (CHD). Methionine synthase reductase (MTRR) is essential for the adequate remethylation of homocysteine, which is the dominant pathway for homocysteine removal during early embryonic development. METHODS AND RESULTS: Here, we report that the c.56+781 A>C (rs326119) variant of intron-1 of MTRR significantly increases the risk of CHD in the Han Chinese population. In 3 independent case-control studies involving a total of 2340 CHD patients and 2270 healthy control participants from different geographic areas, we observed that patients carrying the heterozygous AC and homozygous CC genotype had a 1.40-fold (odds ratio=1.40; P=2.32×10(-7)) and 1.84-fold (odds ratio=1.84; P=2.3×10(-11)) increased risk, respectively, of developing CHD than those carrying the wild-type AA genotype. Both in vivo quantitative real-time polymerase chain reaction analysis of MTRR mRNA in cardiac tissue samples from CHD patients and in vitro luciferase assays in transfected cells demonstrated that the c.56+781 C allele profoundly decreased MTRR transcription. Further analysis demonstrated that the c.56+781 C allele manifested reduced CCAAT/enhancer binding protein-α binding affinity. In addition, healthy individuals with the homozygous CC genotype had significantly elevated levels of plasma homocysteine compared with the wild-type AA carriers. CONCLUSIONS: We have demonstrated that the MTRR c.56+781 A>C variant is an important genetic marker for increased CHD risk because this variant results in functionally reduced MTRR expression at the transcriptional level. Our results accentuate the significance of functional single-nucleotide polymorphisms in noncoding regions of the homocysteine/folate metabolism pathway core genes for their potential contributions to the origin of CHD.
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Povo Asiático/genética , Povo Asiático/estatística & dados numéricos , Ferredoxina-NADP Redutase/genética , Defeitos dos Septos Cardíacos/etnologia , Defeitos dos Septos Cardíacos/genética , Adulto , Animais , Estudos de Casos e Controles , Células Cultivadas , Criança , China/epidemiologia , Ferredoxina-NADP Redutase/metabolismo , Variação Genética , Genótipo , Células HEK293 , Defeitos dos Septos Cardíacos/metabolismo , Homocisteína/sangue , Humanos , Íntrons/genética , Miócitos Cardíacos/citologia , Polimorfismo de Nucleotídeo Único/genética , Ratos , Fatores de Risco , Ativação Transcricional/genéticaRESUMO
Photocatalytic reactions convert solar energy into chemical energy through a clean and green reaction process. Photocatalytic technology based on semiconductor materials provides us with a new idea in energy utilization and environmental governance. It was found that vanadium pentoxide (V2O5) has a narrow band gap, wide response range in the visible region, high oxygen density in the V2O5 lattice, high oxidation state of V5+, small energy requirement, and superior catalytic activity in partial oxidation. Therefore, the utilization rate of sunlight and photocatalytic oxidation can be greatly improved using V2O5 materials. However, the narrow band gap of V2O5 also makes it easier for the photogenerated electrons and holes to recombine in the excited state, and the stored energy is instantly consumed by carrier recombination. Therefore, how to promote the carrier separation of V2O5 and improve the photocatalytic efficiency are the key problems to be solved. Herein, several methods to improve the photocatalytic performance of V2O5 are reviewed, including metallic ion doping, non-metallic ion doping, semiconductor recombination, and noble metal deposition. Finally, it is suggested that future research directions should focus on a variety of modification methods simultaneously to promote photocatalytic efficiency and lower the cost, which will enable V2O5 to have a broad development prospect in the field of photocatalysis.
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The energy crisis is a the worldwide problem which needs humans to solve immediately. To solve this problem, it is necessary to develop energy storage batteries. It is worth mentioning the aqueous rechargeable zinc ion batteries (ARZBs) which have some advantages, such as low cost, good safety and no need for an organic electrolyte as in the traditional lithium-ion batteries. However, it is still a challenge to find suitable and reliable electrode materials. In this work, as-prepared H2V3O8 nanorods and MXene composites are used as cathode materials in ARZBs which were designed well using a hydrothermal method after optimizing the reaction time. The results showed that H2V3O8/MXene ARZBs could provide a good transport path for zinc ions, which were based on special 1D H2V3O8 nanorods and 2D multi-layered MXene materials, which exhibited an outstanding initial specific discharge capacity of 373 mA h g-1 at 200 mA g-1, good rate capability and a long lifecycle with only 15.8% capacity decay at 500 mA g-1 after 5000 cycles. The H2V3O8/MXene composites with a good electrochemical performance bring insight into their promising applications for energy storage batteries. They provided enhanced rate performance and excellent cycling stability, which was ascribed to the multi-step and multi-mode zinc ion insertion/extraction process. This was confirmed by the use of the 1D/2D integrated structure of the H2V3O8/MXene composites, which was conductive to zinc ion diffusion.
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Nanorod-supported (Pt-Pd)/CeO2 catalysts were synthesized by a simple method of dealloying Al91.7Ce8 Pt X Pd0.3-X (X = 0, 0.075, 0.1, 0.15, 0.2, 0.3) alloy ribbons. SEM and TEM characterization implied that after calcination treatment, the achieved resultants exhibited interspersed nanorod structures with a rich distribution of nanopores. Catalytic tests showed that the (Pt0.1-Pd0.2)/CeO2 catalyst calcined at 300 °C exhibited the highest catalyst activity for CO oxidation when compared with other catalysts prepared at different noble metal ratios or calcined at other temperatures, whose complete reaction temperature was as low as 100 °C. The outstanding catalytic performance is ascribed to the stable framework structure, rich gas pathways and collaborative effect between the noble Pt and Pd bimetals.
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[This corrects the article DOI: 10.1039/D3RA04143C.].
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Electrodes that offer quick ion transport, a large surface area, and excellent electrical conductivity support high performance aqueous rechargeable lithium batteries. LiFePO4 (LFP) nanoparticles have been successfully coated with carbon by a chemical sol-gel route, and assembled on graphite by an ultrasonication method to acquire LFP/C/graphite. This LFP/C/graphite composite exhibits exceptional electrochemical performance at various current densities (1C to 20C). LFP/C/graphite delivers better capacity that is higher than that of LFP/C particles and high stability after 60 cycles at a current density of 1C for aqueous rechargeable lithium batteries as a cathode material. The graphite serves as a good volume buffer in improving the lithium performance of LFP/C/graphite during the charge/discharge process. The LFP/C/graphite composite shows high rate capability at 20C that returned to the initial capacity at 1C after 25 cycles with coulombic efficiency of 97%. Therefore, this effort presents a super low-cost route to fabricate high performance cathode materials in aqueous rechargeable lithium batteries and other energy storage appliances.
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Two new species of the genus Smaragdina Chevrolat from China are reported: S.hejingensis Duan, Wang & Zhou sp. nov. from Xinjiang, and S.magnipunctata Duan, Wang and Zhou sp. nov. from Yunnan. Six species, S.divisa (Jacoby), S.insulana Medvedev, S.kimotoi Lopatin, S.laboissierei (Pic), S.laosensis Kimoto & Gressitt, and S.oculata Medvedev are new country records for China. Color illustrations and line drawings of general habitus and morphological details are given. All types of two new species are deposited in the collection of Institute of Zoology, Chinese Academy of Sciences (IZ-CAS).
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The mainland Chinese fauna of the leaf beetle genus Adiscus Gistel, 1857 is revised and three new species described: Adiscus daofuensis Duan Zhou, new species from Sichuan, Gansu and Henan, A. ningshanensis Duan Zhou, new species from Shaanxi, and A. tanae Duan Zhou, new species from Tibet. One species is newly recorded from China: A. pubiventris Medvedev, 2008. The mainland Chinese fauna of Adiscus is 35 species, almost all of which are redescribed. Color illustrations and line drawings are provided and a key to all 35 Chinese mainland species. Types of the new species are deposited in the Institute of Zoology, Chinese Academy of Sciences.
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Besouros , Distribuição Animal , Estruturas Animais , Animais , ChinaRESUMO
Seasonal H3N2 influenza evolves rapidly, leading to an extremely poor vaccine efficacy. Substitutions employed during vaccine production using embryonated eggs (i.e., egg passage adaptation) contribute to the poor vaccine efficacy (VE), but the evolutionary mechanism remains elusive. Using an unprecedented number of hemagglutinin sequences (n = 89,853), we found that the fitness landscape of passage adaptation is dominated by pervasive epistasis between two leading residues (186 and 194) and multiple other positions. Convergent evolutionary paths driven by strong epistasis explain most of the variation in VE, which has resulted in extremely poor vaccines for the past decade. Leveraging the unique fitness landscape, we developed a novel machine learning model that can predict egg passage substitutions for any candidate vaccine strain before the passage experiment, providing a unique opportunity for the selection of optimal vaccine viruses. Our study presents one of the most comprehensive characterizations of the fitness landscape of a virus and demonstrates that evolutionary trajectories can be harnessed for improved influenza vaccines.
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Vacinas contra Influenza , Influenza Humana , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hemaglutininas , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/genéticaRESUMO
K0.25V2O5 (KVO) and K0.25V2O5/graphene oxide (KVO/GO) have been successfully synthesized by a chemical coprecipitation method and a subsequent calcination process. The structure and morphology of KVO and KVO/GO were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The as-obtained vanadate and vanadate modified by GO materials were used as anodes with LiMn2O4 as a cathode and saturated LiNO3 as an electrolyte to assemble an aqueous rechargeable lithium-ion battery (ARLB). The cyclic voltammogram curves of both KVO and KVO/GO electrodes exhibited three pairs of redox peaks corresponding to charge/discharge platforms. We found that a small amount of graphene oxide added improved the electrochemical performance more significantly than excess graphene oxide. The as-prepared KVO/GO//LiMn2O4 could not only improve the initial discharge capacity but could also reduce the attenuation at a high current density. Furthermore, the ARLB with a KVO/GO anode exhibited an excellent rate performance and super long cycle life. These good electrochemical properties of this new ARLB system actually provided feasibility for application in large-scale power sources and energy storage devices.
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Aqueous rechargeable lithium-ion batteries (ARLBs) are regarded as a competitive challenger for large-scale energy storage systems because of their high safety, modest cost, and green nature. A kind of modified composite material composed of H2V3O8 nanorods and graphene sheets (HVO/G) has been effectively made by a one-step hydrothermal method and following calcination at 523 K. XRD, SEM, TEM, and TG are used to determine the phase structures and morphologies of the composite materials. Owing to the advantage of the layered structure of H2V3O8 nanorods, the excellent conductivity of the graphene sheets, and the 3D network structure of the modified composite, the ARLBs with HVO/G can deliver an adequate specific capacity of 271 mA h g-1 at 200 mA g-1 and have a retention rate of 73.4% after 50 cycles. The average discharge capacity of ARLB with HVO/G as anode has a considerable improvement over that of HVO/CNTs and HVO, whatever the current rate used. Moreover, we find that the diffusion coefficient of lithium-ion increases by an order of magnitude through the theoretical calculation for HVO/G ARLB. The new ARLB with HVO/G electrode is a potential energy storage system with great advantages, such as simple preparation, easy assembly process, excellent safety and low-cost environmental protection.