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1.
J Phys Chem Lett ; 13(46): 10811-10815, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36378687

RESUMO

van der Waals (vdW) Josephson junctions can possibly accelerate the development of an advanced superconducting device that utilizes the unique properties of two-dimensional (2D) transition metal dichalcogenide (TMD) superconductors such as spin-orbit coupling and spin-valley locking. Here, we fabricate vertically stacked NbS2/NbS2 Josephson junctions using a modified all-dry transfer technique and characterize the device performance via systematic low-temperature transport measurements. The experimental results show that the superconducting transition temperature of the NbS2/NbS2 Josephson junction is 5.84 K, and the critical current density reaches 3975 A/cm2 at 2 K. Moreover, we extract a superconducting energy gap Δ = 0.58 meV, which is considerably smaller than that expected from the single band s-wave Bardeen-Cooper-Schrieffer (BCS) model (Δ = 0.89 meV).

2.
Cytotechnology ; 74(4): 491-502, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36110152

RESUMO

Proteasome 20S Subunit Beta 2 (PSMB2) has been suggested to play several roles in cancer. However, the role of PSMB2 and its underlying mechanisms in gastric cancer have not been studied. In this study, qRT-PCR was employed to detect the expression of genes that encode for 26 s proteasome subunit proteins. PSMB2 expression and its prognostic ability were assessed by collecting patient tissue samples and reviewing the TCGA and Kaplan-Meier Plotter databases. Immunofluorescence and western blotting experiments were performed to evaluate the expression of PSMB2 in human gastric cancer cells and normal gastric epithelial cells. Subsequently, PSMB2 was knocked down in HGC-27 and SNU-1 cells and overexpressed in N-87 and AGS cells. Proteasome activity assays, 5-Ethynyl-2'-deoxyuridine staining, and TUNEL assays were used to assess proteasome activity, cell proliferation, and apoptosis. Tumor xenograft assays were conducted to evaluate PSMB2 function in vivo. Our results showed that a total of 8 genes encoding for the 26 s proteasome subunit protein were highly expressed in a variety of gastric cancer cells. Next, PSMB2 was selected as the focus of subsequent studies which showed that PSMB2 was highly expressed in samples of gastric cancer tissue. Furthermore, a review of the TCGA database revealed that a high level of PSMB2 expression was associated with a poor clinical prognosis. Our results indicated that PSMB2 overexpression promoted proteasome activity, cell proliferation, and suppressed the apoptosis of gastric cancer cells, while those effects were reversed by treatment with a proteasome inhibitor (MG132). In contrast, PSMB2 knockdown produced the opposite effects and also blocked NRF1 activation. Moreover, PSMB2 knockdown inhibited tumor growth in vivo, decreased PSMB2 expression and cell proliferation, and promoted apoptosis in tumor tissues. Our findings revealed the role played by PSMB2 in gastric cancer and suggest PSMB2 as a new target molecule for use in diagnosing and treating gastric cancer.

3.
Sci Total Environ ; 851(Pt 1): 158357, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36041598

RESUMO

Calcium looping (CaL) belongs to a promising high-temperature CO2 capture technology because of adopting cheap and extensive source CaO-based sorbents. However, CaO-based sorbents are prone to occur the issues of sintering and elutriation in the fluidized-bed reactors. To further enhance the practicability, the Zr-supported, CaO-based sorbent pellets were produced using the graphite-moulding method. Different synthesis modes (i.e., sol-gel, hydration-mixing, and wet-mixing) were compared for preparing CaO-based composite slurry before pelletization. Sol-gel is the promising synthesis mode to prepare Zr-supported, CaO-based pellets with outstanding CO2 capture performance due to achieving a more uniform distribution of inert CaZrO3 spacer. Moreover, the Zr-based stabilizer content within sorbent pellets produced by the combined method of sol-gel and graphite-moulding was further studied. The higher content of Zr-based stabilizer promotes the enhancement of cyclic stability and mechanical strength of Zr-supported, CaO-based pellets. After 17 cycles, the sorbent pellets containing 20 wt% of Zr-based stabilizer display a high CaO carbonation conversion of 74.1 %. Moreover, CaO-based pellets with 20 wt% of Zr-based stabilizer possess a higher compression strength of 4.84 ± 1.08 MPa, which is as high as 1.8 times that of the pellets with 5 wt% of Zr-based stabilizer.


Assuntos
Compostos de Cálcio , Grafite , Adsorção , Cálcio , Dióxido de Carbono , Óxidos
4.
Nanotechnology ; 33(35)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35609501

RESUMO

Large-area high-quality graphene enabled by chemical vapor deposition (CVD) can possibly pave the path for advanced flexible electronics and spintronics. CVD-grown method utilizing liquid carbon precursor has recently been demonstrated as an appealing choice for mass graphene production, thanks to its low cost and safe operation. However, the quality of the graphene film has been the major obstacle for the implementation of the liquid-precursor-based CVD method. Here we report the growth of centimeter-scale easily-transferable single-layer graphene (SLG) using acetone as a liquid carbon precursor. The dry-transfer technique was used to prepare the graphene device. The typical mobility of the dry-transferred SLG device is as high as 12 500 cm2V-1s-1at room temperature. Thanks to the high quality of the device, the robust quantum Hall effect can survive up to room temperature. The excellent device quality also enables us to observe the Shubnikov-de Haas oscillation in the low magnetic field regime and systemically study the leading scattering mechanism. We extracted both the transport scattering timeτtand the quantum scattering timeτqover a wide range of carrier density. The ratio of the scattering times suggests that the charged-impurity resided near the surface of the graphene restricted the device performance.

5.
Future Med Chem ; 14(6): 407-419, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35192400

RESUMO

Background: Colorectal cancer (CRC) is a malignancy with high mortality. TSPYL2 participates in tumor suppression but its role in CRC remains unknown. Methodology & results: TSPYL2 was downregulated and SIRT1 was upregulated in gefitinib drug-resistant (GEF-DR) tissues of patients with CRC. The GEF-resistant cells, HCT116 and HCT-15, were successfully established. The knockdown of TSPYL2 promoted resistance to GEF in CRC cells. Interestingly, immunofluorescence and western blot assays demonstrated that TSPYL2 inhibited DNA damage repair in HCT-15 and HCT116 GEF-resistant cells. Mechanically, TSPYL2 reduced the resistance to GEF and inhibited DNA damage repair via suppressing SIRT1-mediated FOXO3 deacetylation. TSPYL2 consistently inhibited tumor growth and decreased resistance to GEF in vivo. Conclusion: TSPYL2 reduced resistance to GEF and suppressed DNA damage through downregulating SIRT1-mediated FOXO3 deacetylation, indicating that TSPYL2 might be a novel therapeutic target in CRC.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Sirtuína 1 , Dano ao DNA , Proteína Forkhead Box O3 , Gefitinibe/farmacologia , Células HCT116 , Humanos
6.
ACS Appl Mater Interfaces ; 13(33): 39165-39177, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34382393

RESUMO

Electrochemical CO2 reduction enables the conversion of intermittent renewable energy to value-added chemicals and fuel, presenting a promising strategy to relieve CO2 emission and achieve clean energy storage. In this work, we developed nanosized Cu2O catalysts using the hydrothermal method for electrochemical CO2 reduction to alcohols. Cu2O nanoparticles (NPs) of various morphologies that were enclosed with different crystal facets, named as Cu2O-c (cubic structure with (100) facets), Cu2O-o (octahedron structure with (111) facets), Cu2O-t (truncated octahedron structure with both (100) and (111) facets), and Cu2O-u (urchin-like structure with (100), (220), and (222) facets), were prepared by regulating the content of a polyvinyl pyrrolidone (PVP) template. The electrochemical CO2 reduction performance of the different Cu2O NPs was evaluated in the CO2-saturated 0.5 M KHCO3 electrolyte. The as-synthesized Cu2O nanostructures were capable of reducing CO2 to produce alcohols including methanol, ethanol, and isopropanol. The alcohol selectivity of the different Cu2O NPs followed the order of Cu2O-t < Cu2O-u < Cu2O-c < Cu2O-o (with the total Faradaic efficiencies of alcohol products of 10.7, 25.0, 26.2, and 35.4%). The facet-dependent effects were associated with the varied concentrations of oxygen-vacancy defects, different energy barriers of CO2 reduction, and distinct Cu-O bond lengths over the different crystal facets. The desired Cu2O-o catalyst exhibited good reduction activity with the highest partial current density of 0.51 mA/cm2 for alcohols. The Faradaic efficiencies of alcohol products were 4.9% for methanol, 17.9% for ethanol, and 12.6% for isopropanol. The good electrochemical CO2 reduction performance was also associated with the surface reconstruction of Cu2O, which endowed the catalyst with abundant Cu0 and Cu+ sites for promoted CO2 activation and stabilized CO* adsorption for enhanced C-C coupling. This work will provide a new route for enhancing the alcohol selectivity of nanostructured Cu2O catalysts by crystal facet engineering.

7.
Front Psychol ; 11: 1589, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903428

RESUMO

This study aimed to explore relationships between personality type variables and dream structure variables. In the questionnaire experiment (N = 410), we investigated associations between different personality variables in the Myers-Briggs Type Indicator questionnaire (MBTI) and various aspects of dreams in the Mannheim Dream questionnaire (MADRE). The MBTI has four dimensions. In the Extroversion/Introversion (E/I) dimension, I types dreamt more of emotional intensity and passive emotions than E types. In addition, I types may become more distressed in nightmares than E types. E types more frequently shared their dreams with others. In the Sensation/Intuition (S/N) dimension, N types had a more positive attitude toward dreams and can get more novel ideas and help from their dreams than S types. In the dream diary experiment (N = 47), we investigated whether the S/N dimension may influence waking events' incorporation into dreams. External judges decoded paired waking events and dream reports. N types had more metaphorical incorporation than S types. More specifically, N types had more metaphorical expressions in their dreams than S types. This result may be due to the different characteristics between S types and N types. It may provide support for the dream continuity hypothesis.

8.
Exp Cell Res ; 395(2): 112220, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32777225

RESUMO

Capn4, a small regulatory subunit of the calpain proteolytic system, functions as a potential tumor promoter in several cancers. However, the biological functions and molecular mechanisms of Capn4 in gastric cancer (GC) remain poorly understood. In the current study, we found that upregulation of Capn4 was detected frequently in GC tissues, and was associated with significantly worse survival among the GC patients. Multivariate analyses revealed that abundance of Capn4 was an independent predictive marker for the poor prognosis of GC. Further, Capn4 knockdown notably suppressed GC invasion and metastasis in vitro. Consistently, a xenograft assay showed that silencing of Capn4 in GC cells suppressed their dissemination to lung tissue in vivo. Moreover, our results indicated that Capn4 promotes gastric cancer metastasis by increasing MMP9 expression, and demonstrated that MMP9 is crucial for the pro-metastasis role of Capn4 in GC cells. Further investigation revealed that Capn4 regulated MMP9 expression via activation of Wnt/ß-catenin signaling pathway. Mechanistically, we found that Capn4 can decreased ß-catenin ubiquitination to enhance the protein stability of ß-catenin in GC cells. Collectively, Capn4 has a central role in gastric cancer metastasis, which could be a potential diagnostic and therapeutic target for GC.


Assuntos
Calpaína/metabolismo , Metástase Neoplásica/patologia , Neoplasias Gástricas/patologia , Via de Sinalização Wnt/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias Gástricas/metabolismo , Regulação para Cima
9.
Artigo em Inglês | MEDLINE | ID: mdl-30274377

RESUMO

Kaolinite can be used as in-furnace adsorbent to capture gaseous semi-volatile metals during combustion, incineration, or gasification processes for the purposes of toxic metals emission control, ash deposition/slagging/corrosion inhibition, ultrafine particulate matter emission control, and so on. In this work, the adsorptions of typical heavy metals (Pb and Cd) and typical alkali metals (Na and K) by meta-kaolinite were investigated by the DFT calculation. The adsorption energies followed the sequence of NaOH-Si surface > KOH-Si surface > PbO-Al surface ≈ CdO-Al surface ≈ NaOH-Al surface > KOH-Al surface > NaCl-Al surface ≈ Na-Si surface > Na-Al surface > KCl-Al surface > Pb-Al surface > PbCl2-Al surface > CdCl2-Al surface ≈ K-Si surface ≈ PbCl-Al surface > K-Al surface > CdCl-Al surface > NaCl-Si surface > KCl-Si surface > Cd-Al surface. Si surface was found available to the adsorptions of Na, K, and their compounds, although it was invalid to the adsorptions of Pb, Cd, and their compounds. The interactions between adsorbates and surfaces were revealed. Furthermore, the discussion of combining with the experimental data was applied to the subject validity of calculation results and the effect of chlorine on adsorption and the effect of reducing atmosphere on adsorption.


Assuntos
Poluentes Atmosféricos/química , Cádmio/química , Incineração , Caulim/química , Chumbo/química , Metaloides/química , Adsorção , Cloro , Gases , Material Particulado
10.
J Sleep Res ; 27(3): e12652, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29322673

RESUMO

Many studies have used behavioural experiments to show an attentional bias towards sleep-related stimuli in people with insomnia disorder. A measurement of event-related potential is needed to investigate the cognitive processing mechanism of the attentional process. The present study used the emotional Stroop paradigm and event-related potentials to measure attentional bias towards sleep-negative, sleep-positive and sleep-unrelated neutral words. The study comprised 16 participants with insomnia disorder and 15 participants who were good sleepers. Behavioural data indicated that there was a significant interference effect of sleep-positive words between the insomnia group and the good sleepers, and a marginally significant interference effect from sleep-negative words between groups. In the insomnia group, event-related potential data showed that sleep-negative words elicited higher amplitudes of P1 and N1 components than did sleep-positive and sleep-unrelated words. Our results provide evidence for the early cognitive processing of sleep-negative stimuli, which suggests that the psychological treatment of insomnia could benefit from addressing early hypervigilance towards these stimuli.


Assuntos
Viés de Atenção/fisiologia , Potenciais Evocados/fisiologia , Tempo de Reação/fisiologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Adulto , Ansiedade/diagnóstico , Ansiedade/fisiopatologia , Ansiedade/psicologia , Atenção/fisiologia , Emoções/fisiologia , Feminino , Humanos , Masculino , Sono/fisiologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Teste de Stroop , Adulto Jovem
11.
Chemosphere ; 75(10): 1401-4, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19349064

RESUMO

SEM and N(2) adsorption tests show that the surface area is 3.0 m(2)g(-1) for K(2)CO(3) with structure of monoclinic crystal (PC#1) while that of K(2)CO(3) with structure of hexagonal crystal (PC#2) is 0.95 m(2)g(-1), and the pore volume of PC#1 and PC#2 are 8.0 x 10(-3) and 2.8 x 10(-3)cm(3)g(-1), respectively. Their pore size distribution curves show almost the same trends. Compared with PC#2, the particle morphology of PC#1 is better for the carbonation reaction. However, the carbonation reaction activity of PC#2 is better than that of PC#1. In order to find out the reason, the crystal structure characteristics of these sorbents are investigated with XRD and Inorganic Crystal Structure Database searching. It is shown that the difference in crystal structure causes the difference of carbonation reactivity between PC#1 and PC#2. The present work provides basic data for the technology of CO(2) capture from flue gas using dry potassium-based sorbents.


Assuntos
Dióxido de Carbono/metabolismo , Carbonatos/química , Potássio/química , Adsorção , Cristalografia por Raios X , Recuperação e Remediação Ambiental , Microscopia Eletrônica de Varredura , Nitrogênio/metabolismo , Difração de Raios X
12.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 9): o1665, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21201658

RESUMO

The asymmetric unit of the title compound, C(23)H(18)Br(2)O(2), contains two independent mol-ecules with slightly different conformations. In the absence of classical inter-molecular inter-actions, the crystal packing is stabilized by van der Waals forces.

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