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1.
Small ; 20(27): e2309600, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38403846

RESUMO

Constructing a stable and robust solid electrolyte interphase (SEI) has a decisive influence on the charge/discharge kinetics of lithium-ion batteries (LIBs), especially for silicon-based anodes which generate repeated destruction and regeneration of unstable SEI films. Herein, a facile way is proposed to fabricate an artificial SEI layer composed of lithiophilic chitosan on the surface of two-dimensional siloxene, which has aroused wide attention as an advanced anode for LIBs due to its special characteristics. The optimized chitosan-modified siloxene anode exhibits an excellent reversible cyclic stability of about 672.6 mAh g-1 at a current density of 1000 mA g-1 after 200 cycles and 139.9 mAh g-1 at 6000 mA g-1 for 1200 cycles. Further investigation shows that a stable and LiF-rich SEI film is formed and can effectively adhere to the surface during cycling, redistribute lithium-ion flux, and enable a relatively homogenous lithium-ion diffusion. This work provides constructive guidance for interface engineering strategy of nano-structured silicon anodes.

2.
Small ; 20(8): e2306997, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37823688

RESUMO

MXenes have demonstrated significant potential in electrochemical energy storage, particularly in supercapacitors, owing to their exceptional properties. The surface terminal groups of MXene play a pivotal role in pseudocapacitive mechanism. Considering the hindered electrolyte ion transport caused by -F terminal groups and the limited ion binding sites associated with -O terminal groups, this study proposes a novel strategy of replacing -F with -N terminal groups. The modulated MXene-N electrode, featuring a substantial number of -N terminal groups, demonstrates an exceptionally high gravimetric capacitance of 566 F g-1 (at a scan rate of 2 mV s-1 ) or 588 F g-1 (at a discharge rate of 1 A g-1 ) in 1 м H2 SO4 electrolyte, and the potential window is significantly increased. Furthermore, subsequent spectra analysis and density functional theory calculations are employed to investigate the mechanism associated with -N terminal groups. This work exemplifies the significance of terminal modulation in the context of electrochemical energy storage.

3.
J Cell Physiol ; 238(5): 1046-1062, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36924049

RESUMO

Hyperinsulinemia is a critical risk factor for the pathogenesis of insulin resistance (IR) in metabolic tissues, including the liver. Ethanolamine phosphate phospholyase (ETNPPL), a newly discovered metabolic enzyme that converts phosphoethanolamine (PEA) to ammonia, inorganic phosphate, and acetaldehyde, is abundantly expressed in liver tissue. Whether it plays a role in the regulation of hyperinsulinemia-induced IR in hepatocytes remains elusive. Here, we established an in vitro hyperinsulinemia-induced IR model in the HepG2 human liver cancer cell line and primary mouse hepatocyte via a high dose of insulin treatment. Next, we overexpressed ETNPPL by using lentivirus-mediated ectopic to investigate the effects of ETNPPL per se on IR without insulin stimulation. To explore the underlying mechanism of ETNPPL mediating hyperinsulinemia-induced IR in HepG2, we performed genome-wide transcriptional analysis using RNA sequencing (RNA-seq) to identify the downstream target gene of ETNPPL. The results showed that ETNPPL expression levels in both mRNA and protein were significantly upregulated in hyperinsulinemia-induced IR in HepG2 and primary mouse hepatocytes. Upon silencing ETNPPL, hyperinsulinemia-induced IR was ameliorated. Under normal conditions without IR in hepatocytes, overexpressing ETNPPL promotes IR, reactive oxygen species (ROS) generation, and AKT inactivation. Transcriptome analysis revealed that salt-inducible kinase 1 (SIK1) is markedly downregulated in the ETNPPL knockdown HepG2 cells. Moreover, disrupting SIK1 prevents ETNPPL-induced ROS accumulation, damage to the PI3K/AKT pathway and IR. Our study reveals that ETNPPL mediates hyperinsulinemia-induced IR through the SIK1/ROS-mediated inactivation of the PI3K/AKT signaling pathway in hepatocyte cells. Targeting ETNPPL may present a potential strategy for hyperinsulinemia-associated metabolic disorders such as type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperinsulinismo , Resistência à Insulina , Animais , Humanos , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Hepatócitos/metabolismo , Hiperinsulinismo/genética , Hiperinsulinismo/metabolismo , Insulina/metabolismo , Resistência à Insulina/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
4.
Inorg Chem ; 62(3): 1113-1121, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36351259

RESUMO

Atomically dispersed organometallic clusters can provide well-defined nuclearity of active sites for both fundamental studies as well as new regimes of activity and selectivity in chemical transformations. More recently, dinuclear clusters adsorbed onto solid surfaces have shown novel catalytic properties resulting from the synergistic effect of two metal centers to anchor different reactant species. Difficulty in synthesizing, stabilizing, and characterizing isolated atoms and clusters without agglomeration challenges allocating catalytic performance to atomic structure. Here, we explore the stability of dinuclear rhodium and iridium clusters adsorbed onto layered titanate and niobate supports using molecular precursors. Both systems maintain their nuclearity when characterized using aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Statistical analysis of HAADF-STEM images revealed that rhodium and iridium dimers had mean cluster-to-cluster distances very similar to what is expected from a random distribution of atoms over a large area, indicating that they are dispersed without aggregation. The stability of dinuclear rhodium clusters supported on titanate nanosheets was also investigated by X-ray absorption fine structure (EXAFS), DRIFTS, and first-principles calculations. Both X-ray absorption spectroscopy and HAADF-STEM simulations, guided by density functional theory (DFT)-optimized structure models, suggested that rhodium dimers adsorb onto the nanosheets in an end-on binding mode that is stable up to 100 °C under reducing conditions. This study highlights that crystalline nanosheets derived from layered metal oxides can be used as model supports to selectively stabilize dinuclear clusters, which could have implications for heterogeneous catalysis.


Assuntos
Ródio , Ródio/química , Irídio/química , Óxidos/química , Catálise
5.
Plant Cell Rep ; 42(1): 107-121, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36284021

RESUMO

KEY MESSAGE: Identification, characterization and osmotic stress responsive expression of growth-regulating factor genes in grape. The growth and fruit production of grape vine are severely affected by adverse environmental conditions. Growth-regulating factors (GRFs) play a vital role in the regulation of plant growth, reproduction and stress tolerance. However, their biological functions in fruit vine crops are still largely unknown. In the present study, a total number of nine VvGRFs were identified in the grape genome. Phylogenetic and collinear relationship analysis revealed that they formed seven subfamilies, and have gone through three segmental duplication events. All VvGRFs were predicted to be nucleic localized and contained both the conserved QLQ and WRC domains at their N-terminals, one of the typical structural features of GRF proteins. Quantitative real-time PCR analyses demonstrated that all VvGRFs, with a predominant expression of VvGRF7, were constitutively expressed in roots, leaves and stems of grape plants, and showed responsive expression to osmotic stress. Further growth phenotypic analysis demonstrated that ectopic expression of VvGRF7 promoted the growth and sensitivity of transgenic Arabidopsis plants to osmotic stress. Our findings provide important information for the future study of VvGRF gene functions, and potential gene resources for the genetic breeding of new fruit vine varieties with improved fruit yield and stress tolerance.


Assuntos
Arabidopsis , Vitis , Vitis/genética , Filogenia , Pressão Osmótica , Melhoramento Vegetal , Frutas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
BMC Biol ; 20(1): 214, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36175945

RESUMO

BACKGROUND: Odorant receptors (ORs) as odorant-gated ion channels play a crucial role in insect olfaction. They are formed by a heteromultimeric complex of the odorant receptor co-receptor (Orco) and a ligand-selective Or. Other types of olfactory receptor proteins, such as ionotropic receptors (IRs) and some gustatory receptors (GRs), are also involved in the olfactory system of insects. Orco as an obligatory subunit of ORs is highly conserved, providing an opportunity to systematically evaluate OR-dependent olfactory responses. RESULTS: Herein, we successfully established a homozygous mutant (Orco-/-) of Helicoverpa armigera, a notorious crop pest, using the CRISPR/Cas9 gene editing technique. We then compared the olfactory response characteristics of wild type (WT) and Orco-/- adults and larvae. Orco-/- males were infertile, while Orco-/- females were fertile. The lifespan of Orco-/- females was longer than that of WT females. The expressions of most Ors, Irs, and other olfaction-related genes in adult antennae of Orco-/- moths were not obviously affected, but some of them were up- or down-regulated. In addition, there was no change in the neuroanatomical phenotype of Orco-/- moths at the level of the antennal lobe (including the macroglomerular complex region of the male). Using EAG and SSR techniques, we discovered that electrophysiological responses of Orco-/- moths to sex pheromone components and many host plant odorants were absent. The upwind flight behaviors toward sex pheromones of Orco-/- males were severely reduced in a wind tunnel experiment. The oviposition selectivity of Orco-/- females to the host plant (green pepper) has completely disappeared, and the chemotaxis toward green pepper was also lost in Orco-/- larvae. CONCLUSIONS: Our study indicates that OR-mediated olfaction is essential for pheromone communication, oviposition selection, and larval chemotaxis of H. armigera, suggesting a strategy in which mate searching and host-seeking behaviors of moth pests could be disrupted by inhibiting or silencing Orco expression.


Assuntos
Mariposas , Receptores Odorantes , Atrativos Sexuais , Animais , Feminino , Masculino , Eletrólitos , Proteínas de Insetos/metabolismo , Canais Iônicos , Larva/genética , Larva/metabolismo , Ligantes , Mariposas/genética , Mutagênese , Feromônios , Receptores Odorantes/metabolismo , Olfato
7.
Small ; 18(4): e2105696, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34837326

RESUMO

The oxygen evolution reaction (OER) plays a key role in many electrochemical energy conversion systems, but it is a kinetically sluggish reaction and requires a large overpotential to deliver appreciable current, especially for the non-noble metal electrocatalysts. In this study, the authors report a surface phase engineering strategy to improve the OER performance of transition metal nitrides (TMNs). The iron-nickel nitrides/alloy nanospheres (FeNi3 -N) wrapped in carbon are synthesized, and the optimized FeNi3 -N catalyst displays dual-phase nitrides on the surface induced by atom migration phenomenon, resulting from the different migration rates of metal atoms during the nitridation process. It shows excellent OER performance in alkaline media with an overpotential of 222 mV at 10 mA cm-2 , a small Tafel slope of 41.53 mV dec-1 , and long-term durability under high current density (>0.5 A cm-2 ) for at least 36 h. Density functional theory (DFT) calculations further reveal that the dual-phase nitrides are favorable to decrease the energy barrier, modulate the d-band center to balance the absorption and desorption of the intermediates, and thus promote the OER electrochemical performance. This strategy may shed light on designing OER and other catalysts based on surface phase engineering.

8.
Small ; 17(13): e2007858, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33690975

RESUMO

Transition metal phosphides (TMPs), especially the dual-metal TMPs, are highly active non-precious metal oxygen evolution reaction (OER) electrocatalysts. Herein, an interesting atom migration phenomenon induced by Kirkendall effect is reported for the preparation of cobalt-iron (Co-Fe) phosphides by the direct phosphorization of Co-Fe alloys. The compositions and distributions of the Co and Fe phosphides phases on the surfaces of the electrocatalysts can be readily controlled by Cox Fey alloys precursors and the phosphorization process with interesting atom migration phenomenon. The optimized Co7 Fe3 phosphides exhibit a low overpotential of 225 mV at 10 mA cm-2 in 1 m KOH alkaline media, with a small Tafel slope of 37.88 mV dec-1 and excellent durability. It only requires a voltage of 1.56 V to drive the current density of 10 mA cm-2 when used as both anode and cathode for overall water splitting. This work opens a new strategy to controllable preparation of dual-metal TMPs with designed phosphides active sites for enhanced OER and overall water splitting.

9.
Proc Natl Acad Sci U S A ; 115(1): 180-185, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29255036

RESUMO

Aberrant expression of microRNAs (miRNAs) underlies a spectrum of human diseases including organ fibrosis, and hepatic stellate cells (HSCs) are the main effectors of hepatic fibrosis. Here, we showed that the expression of host miR-351 in HSCs was markedly reduced during the early stage of Schistosoma infection. However, this expression was significantly increased during the later stage of infection (after 52 d of infection). The elevated levels of miR-351 promoted hepatic fibrosis by targeting the vitamin D receptor (VDR), which is an antagonist of SMAD signaling. Importantly, efficient and sustained inhibition of miR-351 in liver tissues using the highly hepatotropic recombinant adeno-associated virus serotype 8 (rAAV8), alleviated the hepatic fibrosis, partially protecting the host from lethal schistosomiasis. In addition, we found that miR-351 is negatively regulated by IFN-γ in HSCs during infection. At the early stage of infection, the elevated levels of IFN-γ inhibited the expression of miR-351 in HSCs through activation of signal transducer and activator of transcription 1 and induction of IFN regulatory factor 2, which binds the promotor of pre-miR-351 Our study provides insights into the mechanisms by which miR-351 regulates schistosomiasis hepatic fibrosis and highlights the potential of rAAV8-mediated miR-351 inhibition as a therapeutic intervention for fibrotic diseases.


Assuntos
Células Estreladas do Fígado/imunologia , Cirrose Hepática/imunologia , Fígado/imunologia , MicroRNAs/imunologia , Receptores de Calcitriol/imunologia , Schistosoma/imunologia , Esquistossomose/imunologia , Animais , Células Estreladas do Fígado/patologia , Interferon gama/imunologia , Fígado/parasitologia , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Esquistossomose/patologia , Esquistossomose/terapia
10.
J Hepatol ; 72(3): 519-527, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31738999

RESUMO

BACKGROUND & AIMS: MicroRNAs (MiRNAs) derived from parasites, and even from plants, have been detected in body fluids and are known to modulate host genes. In this study, we aimed to investigate if the schistosome miRNAs are involved in the occurrence and progression of hepatic fibrosis during Schistosoma japonicum (S. japonicum) infection. METHODS: The presence of miRNAs from S. japonicum (sja-miRNAs) in hepatic stellate cells (HSCs) was detected by RNA sequencing. sja-miRNAs were screened by transfecting HSCs with sja-miRNA mimics. The role of sja-miR-2162 in hepatic fibrosis was evaluated by either elevating its expression in naïve mice or by inhibiting its activity in infected mice, through administration of recombinant adeno-associated virus serotype 8 vectors expressing sja-miR-2162 or miRNA sponges, respectively. RESULTS: We identified a miRNA of S. japonicum, sja-miR-2162, that was consistently present in the HSCs of infected mice. Transfection of sja-miR-2162 mimics led to activation of HSC cells in vitro, characterized by elevation of collagens and α-SMA. The rAAV8-mediated delivery of sja-miR-2162 to naïve mice induced hepatic fibrosis, while sustained inhibition of sja-miR-2162 in infected mice attenuated hepatic fibrosis. The transforming growth factor beta receptor III (TGFBR3), a negative regulator of TGF-ß signaling, was a direct target of sja-miR-2162 in HSCs. CONCLUSIONS: This study demonstrated that pathogen-derived miRNAs directly promote hepatic fibrogenesis in a cross-species manner, and their efficient and sustained inhibition might present a promising therapeutic intervention for infectious diseases. LAY SUMMARY: A schistosome-specific microRNA, sja-miR-2162, is consistently present in the hepatic stellate cells of mice infected with S. japonicum, where it promotes hepatic fibrosis in the host through cross-species regulation of host fibrosis-related genes. The efficient and sustained inhibition of pathogen-derived micRNAs may represent a novel therapeutic intervention for infectious diseases.


Assuntos
Interações Hospedeiro-Parasita/genética , Cirrose Hepática/genética , Cirrose Hepática/parasitologia , MicroRNAs/genética , Proteoglicanas/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Schistosoma japonicum/genética , Esquistossomose Japônica/complicações , Actinas/biossíntese , Animais , Linhagem Celular , Colágeno/biossíntese , Dependovirus/genética , Vetores Genéticos , Células Estreladas do Fígado/parasitologia , Humanos , Masculino , Camundongos , Ratos , Esquistossomose Japônica/parasitologia , Análise de Sequência de RNA , Transdução de Sinais/genética , Transfecção
11.
PLoS Pathog ; 14(3): e1006957, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29554131

RESUMO

The type 2 immune response is the central mechanism of disease progression in schistosomiasis, but the signals that induce it after infection remain elusive. Aberrant microRNA (miRNA) expression is a hallmark of human diseases including schistosomiasis, and targeting the deregulated miRNA can mitigate disease outcomes. Here, we demonstrate that efficient and sustained elevation of miR-203-3p in liver tissues, using the highly hepatotropic recombinant adeno-associated virus serotype 8 (rAAV8), protects mice against lethal schistosome infection by alleviating hepatic fibrosis. We show that miR-203-3p targets interleukin-33 (IL-33), an inducer of type 2 immunity, in hepatic stellate cells to regulate the expansion and IL-13 production of hepatic group 2 innate lymphoid cells during infection. Our study highlights the potential of rAAV8-mediated miR-203-3p elevation as a therapeutic intervention for fibrotic diseases.


Assuntos
Células Estreladas do Fígado/patologia , Interleucina-33/metabolismo , Fígado/patologia , MicroRNAs/genética , Schistosoma/patogenicidade , Esquistossomose/patologia , Animais , Células Cultivadas , Regulação para Baixo , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/parasitologia , Interleucina-33/genética , Fígado/metabolismo , Fígado/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Esquistossomose/genética , Esquistossomose/metabolismo , Esquistossomose/parasitologia
12.
Langmuir ; 36(48): 14710-14716, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33227197

RESUMO

Hydrodeoxygenation (HDO) of bio-oil is a crucial step for improving the bio-fuel quality, but developing highly dispersed Pt-based catalysts with high selectivity for target alkanes remains a great challenge. This study presents a fast surfactant-free method to prepare the MoS2-supported Pt catalyst for HDO. Ultrafine Pt nanoparticles with sizes of <5 nm can be readily grown on chemically exfoliated MoS2 nanosheets (NSs) via the direct microwave-assisted thermal reduction. The obtained Pt NPs/MoS2 composites show excellent catalytic performance in the conversion of palmitic acid, and the best selectivity (also the yield) of hexadecane and pentadecane is 80.56 and 19.43%, respectively.

13.
Small ; 14(2)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29149471

RESUMO

The development of highly efficient and durable non-noble metal electrocatalysts for the hydrogen evolution reaction (HER) is significant for clean and renewable energy research. This work reports the synthesis of N-doped graphene nanosheets supported N-doped carbon coated cobalt phosphide (CoP) nanoparticles via a pyrolysis and a subsequent phosphating process by using polyaniline. The obtained electrocatalyst exhibits excellent electrochemical activity for HER with a small overpotential of -135 mV at 10 mA cm-2 and a low Tafel slope of 59.3 mV dec-1 in 0.5 m H2 SO4 . Additionally, the encapsulation of N-doped carbon shell prevents CoP nanoparticles from corrosion, exhibiting good stability after 14 h operation. Moreover, the as-prepared electrocatalyst also shows outstanding activity and stability in basic and neutral electrolytes.

14.
Nanotechnology ; 29(50): 505603, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30272574

RESUMO

A Cu2O based multi-layered photocathode was fabricated with a layer-by-layer assembly method for enhanced photoelectrochemical (PEC) hydrogen evolution. Au was first electrodeposited on the fluorine-doped tin oxide glass to decrease the electrochemical impedance of the Cu2O photocathode. A layer of TiO2 was then coated to increase the light-to-electricity energy conversion efficiency and the chemical stability by forming a p-n junction with Cu2O. Exfoliated WS2 nanosheets obtained from lithium insertion were then coated as the electron acceptor to facilitate the hydrogen evolution. This photocathode is effective for PEC hydrogen evolution, and a photocurrent of -10 mA cm-2 can be obtained at -0.33 V versus RHE in a phosphorus buffer (pH = 6.0) under visible light (λ ≥ 420 nm, 100 mW cm-2) on the optimized photocathode.

15.
Gynecol Endocrinol ; 34(1): 36-39, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28649890

RESUMO

Ghrelin, an endoggenous for the growth hormone secretagogue receptor, has been shown to participate in the regulation of energy homeostasis and pituitary hormone secretion. Obestatin, encoded by the same gene as ghrelin, is described as a physiological opponent of ghrelin. Ghrelin and obestatin are altered in polycystic ovary syndrome (PCOS), which is characterized by insulin resistance and pituitary hormone secretion disorder. The aim of this study was to evaluate ghrelin/obestatin imbalance in relation to insulin resistance and pituitary hormone in adolescence with PCOS. This restrospective case-control study included 33 adolescence with PCOS and 38 control adolescence. Ghrelin and obestatin concentrations in serum were determined by RIA, and the serum fasting glucose and Insulin were determined by the glucose oxidase color method and INS-EASIA. The serum LH and FSH were measured by highly specific hemiluminescence immunoassays. We found that the serum ghrelin levels and ghrelin/obestatin ratio were significant lower in PCOS group than in control group, and the serum obestatin levels were significant higher in PCOS group than in control group. The ghrelin/obestatin ratios were negatively correlation with LH/FSH ratio and insulin resistant index in PCOS group. The findings of this study suggest that ghrelin/obestatin imbalance may play a role in pathogenesis of adolescent PCOS.


Assuntos
Grelina/sangue , Síndrome do Ovário Policístico/sangue , Anormalidades Múltiplas , Adolescente , Glicemia/análise , Estudos de Casos e Controles , Metabolismo Energético , Fácies , Jejum , Feminino , Hormônio Foliculoestimulante/sangue , Homeostase , Humanos , Hipotireoidismo , Insulina/sangue , Resistência à Insulina , Hormônio Luteinizante/sangue , Hormônios Adeno-Hipofisários/deficiência , Hormônios Adeno-Hipofisários/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Estudos Retrospectivos , Fator de Transcrição Pit-1/deficiência , Fator de Transcrição Pit-1/metabolismo
16.
Proteomics ; 17(21)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28941069

RESUMO

Chitin synthases are very important enzymes for chitin synthesis in various species, which makes them a specific target of insecticides. In the present study, the function of the chitin synthase A (CHSA) gene isolated from Mythimna separate is investigated. The majority of dsMysCHSA treated larvae (89.50%) exhibit lethal phenotypes, including three phenotypes with severe cuticle deformations. The dsMysCHSA treatment in adult females affects oogenesis, and significantly reduce the ovary size and the oviposition number compared with controls. To determine how MysCHSA affects female fecundity, combined analyses of RNA-sequencing (RNA-Seq) transcriptome and TMT proteome (tandem mass tags) data in M. separata after treatment with MysCHSA-RNAi is performed. The differentially expressed proteins and genes affect fecundity-related proteins, energy metabolism, fatty acid metabolism, amino sugars, and nucleotide sugar metabolism pathways. Taken together, these results suggest that MysCHSA acts on M. separata ecdysis and fecundity, and has the potential as a target gene for pest control.


Assuntos
Quitina Sintase/análise , Lepidópteros/enzimologia , Lepidópteros/fisiologia , Animais , Quitina Sintase/genética , Quitina Sintase/metabolismo , Feminino , Fertilidade , Proteoma/análise , Transcriptoma
17.
J Am Chem Soc ; 138(15): 5143-9, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27031870

RESUMO

The controlled exfoliation of transition metal dichalcogenides (TMDs) into pristine single- or few-layer nanosheets remains a significant barrier to fundamental studies and device applications of TMDs. Here we report a novel strategy for exfoliating crystalline MoS2 into suspensions of nanosheets with retention of the semiconducting 2H phase. The controlled reaction of MoS2 with substoichiometric amounts n-butyllithium results in intercalation of the edges of the crystals, which are then readily exfoliated in a 45 vol % ethanol-water solution. Surprisingly, the resulting colloidal suspension of nanosheets was found (by electron microscopy and atomic force microscopy) to consist mostly of trilayers. The efficiency of exfoliation of the pre-intercalated sample is increased by at least 1 order of magnitude relative to the starting MoS2 microcrystals, with a mass yield of the dispersed nanosheets of 11-15%.

18.
Nanotechnology ; 27(38): 385604, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27528593

RESUMO

Exfoliated molybdenum disulfide (MoS2) has unique 2H phase and semiconductor properties and potential applications across a wide range of fields. However, the chemically exfoliated MoS2 nanosheets from Li x MoS2 have a 1T phase, and searching for a fast route to get processable 2H-MoS2 nanosheets and its nanocomposites is still an urgent task. This study reports on a simple, fast and efficient microwave strategy to achieve the 1T to 2H phase conversion of MoS2 and the successful preparation of processable 2H-MoS2 nanosheets and their nanocomposites. The method here may be easily changed to achieve the phase change of other exfoliated TMDs.

19.
Chem Soc Rev ; 44(10): 3023-35, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25777748

RESUMO

Scientific interest in graphene as a catalyst and as a catalyst support in heterogeneous catalytic reactions has grown dramatically over the past several years. The present critical review summarizes the multiple roles of graphene in heterogeneous catalysis and highlights the influence of defects, heteroatom-containing functionalities, and graphene's two-dimensional structure on catalytic performance. We first discuss the role and advantages of graphene as a catalyst support, with emphasis on its interactions with the catalytic phases and the influence of mass transfer processes. We then clarify the origin of the intrinsic catalytic activity of graphene in heterogeneous catalytic reactions. Finally we suggest challenges and potential practical applications for graphene in industrial processes.


Assuntos
Engenharia Química/métodos , Grafite , Catálise , Nanopartículas
20.
Nano Lett ; 15(9): 5956-60, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26288218

RESUMO

Exfoliated 2H molybdenum disulfide (MoS2) has unique properties and potential applications in a wide range of fields, but corresponding studies have been hampered by the lack of effective routes to it in bulk quantities. This study presents a rapid and efficient route to obtain exfoliated 2H MoS2, which combines fast sonication-assisted lithium intercalation and infrared (IR) laser-induced phase reversion. We found that the complete lithium intercalation of MoS2 with butyllithium could be effected within 1.5 h with the aid of sonication. The 2H to 1T phase transition that occurs during the lithium intercalation could be also reversed by IR laser irradiation with a DVD optical drive.

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