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1.
Acta Physiol (Oxf) ; : e13784, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34995420

RESUMO

AIM: Galectin-3 (Gal-3) is a biomarker of atrial fibrillation (AF) that mediates atrial inflammation. CD98 is the membrane surface receptor for Gal-3. Nevertheless, the role of the Gal-3/CD98 axis in atrial arrhythmogenesis is unclear. In this study, we investigated the effects of Gal-3/CD98 signalling on atrial pathogenesis. METHODS: Whole cell patch clamp and western blotting were used to analyse calcium/potassium homeostasis and calcium-related signalling in Gal-3-administrated HL-1 atrial cardiomyocytes with/without CD98 neutralized antibodies. Telemetry electrocardiographic recording, Masson's trichrome staining and immunohistochemistry staining of atrium were obtained from mice having received tail-vein injections with Gal-3. RESULTS: Gal-3-treated HL-1 myocytes had a shorter action potential duration, smaller L-type calcium current, increased sarcoplasmic reticulum (SR) calcium content, Na+ /Ca2+ exchanger (NCX) current, transient outward potassium current, and ultrarapid delayed rectifier potassium current than control cells had. Gal-3-treated HL-1 myocytes had greater levels of SR Ca2+ ATPase, NCX, Nav1.5, and NLR family pyrin domain containing 3 (NLRP3) expression and increased calcium/calmodulin-dependent protein kinase II (CaMKII), ryanodine receptor 2 (RyR2), and nuclear factor kappa B (NF-κB) phosphorylation than control cells had. Gal-3-mediated activation of CaMKII/RyR2 pathway was diminished in the cotreatment of anti-CD98 antibodies. Mice that were injected with Gal-3 had more atrial ectopic beats, increased atrial fibrosis, and activated NF-κB/NLRP3 signalling than did control mice (nonspecific immunoglobulin) or mice treated with Gal-3 and anti-CD98 antibodies. CONCLUSION: Gal-3 recombinant protein administration increases atrial fibrosis and arrhythmogenesis through CD98 signalling. Targeting Gal-3/CD98 axis might be a novel therapeutic strategy for patients with AF and high Gal-3 levels.

2.
Sci Rep ; 12(1): 112, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997104

RESUMO

Device quantization of in-memory computing (IMC) that considers the non-negligible variation and finite dynamic range of practical memory technology is investigated, aiming for quantitatively co-optimizing system performance on accuracy, power, and area. Architecture- and algorithm-level solutions are taken into consideration. Weight-separate mapping, VGG-like algorithm, multiple cells per weight, and fine-tuning of the classifier layer are effective for suppressing inference accuracy loss due to variation and allow for the lowest possible weight precision to improve area and energy efficiency. Higher priority should be given to developing low-conductance and low-variability memory devices that are essential for energy and area-efficiency IMC whereas low bit precision (< 3b) and memory window (< 10) are less concerned.

3.
Huan Jing Ke Xue ; 43(1): 424-431, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989527

RESUMO

In order to realize the rapid recovery of ANAMMOX sludge bacterial activity after long-term room temperature storage, three groups of reactors were added to ANAMMOX sludge that had been stored without substrate at room temperature (15-30℃) for 9 months. Among the three groups of reactors, comet fiber carrier and K3 carrier were added to R2 and R3 reactors, respectively, as biological carriers. The effects of different carriers on the recovery rate of ANAMMOX sludge bacterial activity were investigated. The results showed that ANAMMOX reactions in the R2 and R3 reactors began taking place on the 8th and 10th day, respectively, with respective TIN removal rates of 82.25% and 80.92%, which were significantly improved compared with that in the R1 reactor, in which no carrier was added (ANAMMOX reaction started occurring on the 15th day with a TIN removal rate of 80.26%). After 42 days with influent, ρ(NH4+-N) and ρ(NO2--N) respectively increased to 300 mg·L-1 and 396 mg·L-1, and the TIN removal rates of the three groups of reactors were respectively 78.96%, 84.92%, and 84.66%. Microbial community structure analysis showed that the relative abundances of ANAMMOX bacteria in the R2 and R3 reactor were respectively 6.85% and 6.06%, two to four times that in the R1 reactor. The predominant ANAMMOX bacteria in the sludge was Candidatus Jettenia, whose relative abundances in the three groups of reactors were respectively 1.62%, 5.74%, and 5.21%. The results show that ANAMMOX biofilm-granular sludge complex systems constructed by adding carriers can considerably shorten the time for recovering ANAMMOX sludge bacterial activity after long-term room temperature storage without substrate. The carriers effectively promoted the relative abundances of ANAMMOX bacteria in the reactors, whereas the promoting effect of comet fiber carrier was slightly more significant than that of the K3 carrier.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Nitrogênio , Oxirredução
4.
Acta Crystallogr C Struct Chem ; 78(Pt 1): 23-29, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34982046

RESUMO

Two new isostructural complexes, namely, poly[aqua[µ3-2-(4-carboxyphenoxy)terephthalato-κ3O1:O4:O4'](1,10-phenanthroline-κ2N,N')cobalt(II)], [Co(C15H8O7)(C12H8N2)(H2O)]n or [Co(µ3-Hcpota)(phen)(H2O)]n, I, and poly[aqua[µ3-2-(4-carboxyphenoxy)terephthalato-κ3O1:O4:O4'](1,10-phenanthroline-κ2N,N')nickel(II)], [Ni(C15H8O7)(C12H8N2)(H2O)]n or [Ni(µ3-Hcpota)(phen)(H2O)]n, II, have been synthesized by solvothermal reactions. Complexes I and II were fully characterized by IR spectroscopy, elemental analyses, thermogravimetric analyses, and powder and single-crystal X-ray diffraction. They both present two-dimensional structures based on [M2(µ-COO)2]2+ (M = CoII or NiII) dinuclear metal units with a fes topology and a vertex symbol (4·82). Interestingly, the positions of the two dimeric metal motifs and the two partially deprotonated Hcpota2- ligands reproduce regular flying butterfly arrangements flipped upside down and sharing wings in the ab plane. Magnetic studies indicate antiferromagnetic interactions (J = -5.21 cm-1 for I and -11.53 cm-1 for II) in the dimeric units, with Co...Co and Ni...Ni distances of 4.397 (1) and 4.358 (1) Å, respectively, that are related to double syn-anti carboxylate bridges.

5.
Exp Gerontol ; 159: 111683, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34995725

RESUMO

Histidine triad nucleotide-binding protein 1 (HINT1) is regarded as a haplo-insufficient tumour suppressor and is closely associated with many neuropsychiatric disorders, including major depressive disorders. In addition, HINT1 knockout (KO) mice exhibit anxiolytic-like behaviour, antidepression-like behaviour, and enhanced cognitive performance in several studies. However, it is still unclear whether aging contributes to these changes in the emotion and cognition of HINT1 KO mice. This study examined the role of aging in anxiety-like and depression-like behaviours and cognition behaviours in aged HINT1 KO mice compared with young HINT1 KO mice and their wild-type littermates, along with a number of molecular biological methods. In a battery of behavioural tests, aged wild-type mice showed increased anxiety-like and depression-like behaviours and decreased cognitive performance, along with lower expression levels of glutathione peroxidase, enhanced amount of malondialdehyde, and decreased expression levels of brain-derived neurotrophic factor and tyrosine kinase B in the hippocampus and PFC compared to young wild-type mice. HINT1 KO mice showed reduced anxiety-like and depression-like behaviours and enhanced cognitive performance compared to age-matched wild-type mice. In addition, HINT1 KO mice also showed increased GSH-Px and superoxide dismutase, and decreased malondialdehyde, together with enhanced BDNF and Trk-B expression in the hippocampus and PFC. However, when compared with young HINT1 KO mice, aged HINT1 KO mice did not show increased anxiety-like and depression-like behaviours. And there are no differences in the expression level of superoxide dismutase, malondialdehyde, BDNF, and Trk-B between aged and young HINT1 KO mice. In summary, HINT1 deficiency can counteract age-related emotion and cognition dysfunction.

7.
Sci Total Environ ; 806(Pt 3): 150736, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34600985

RESUMO

Humic-reducing microorganisms (HRMs) can utilize humic substance as terminal electron mediator promoting the bioremediation of contaminate, which is ubiquitous in composts. However, the impacts of HRMs on antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in composts and different HRMs community composition following the types of biowastes effected the spread of ARGs have not been investigated. Herein, the dynamics and mobility of ARGs and HRMs during protein-, lignocellulose- and lignin-rich composting were investigated. Result show that ARGs change significantly at the thermophilic phase, and the relative abundance of most ARGs increase during composting. Seven groups of HRMs communities are classified as primary host HRMs of ARGs, and most host HRMs groups from protein-rich composts. Conclusively, regulating methods for inhibiting ARGs spread for different composts are proposed. HRMs show a higher ARGs dissemination capacity in protein-rich composts than lignocellulose- and lignin-rich composts, but the spread of ARGs can be inhibited by regulate physicochemical parameters in protein-rich composts. In contrary, most HRMs have inhibitory effects on ARGs spread in lignocellulose- and lignin-rich composts, and those HRMs can be used as a new agent that inhibits the spread of ARGs. Our results can help in understanding the potential risk spread of ARGs by inoculating functional bacteria derived from different biowastes composts for environmental remediation, given their expected importance to developing a classification-oriented approach for composting different biowastes.


Assuntos
Compostagem , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Substâncias Húmicas , Esterco
8.
Phytomedicine ; 95: 153837, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34883416

RESUMO

BACKGROUND: Moluodan (MLD) is a traditional Chinese patent medicine for the treatment of chronic atrophic gastritis (CAG). However, the mechanism of action (MoA) of MLD for treating CAG still remain unclear. PURPOSE: Elucidate the MoA of MLD for treating CAG based on network pharmacology. STUDY DESIGN: Integrate computational prediction and experimental validation based on network pharmacology. METHODS: Computationally, compounds of MLD were scanned by LC-MS/MS and the target profiles of compounds were identified based on network-based target prediction method. Compounds in MLD were compared with western drugs used for gastritis by hierarchical clustering of target profile. Key biological functional modules of MLD were analyzed, and herb-biological functional module network was constructed to elucidate combinatorial rules of MLD herbs for CAG. Experimentally, MLD's effect on different biological functional modules were validated from both phenotypic level and molecular level in 1- Methyl-3-nitro-1-nitrosoguanidine (MNNG)-induced GES-1 cells. RESULTS: Computational results show that the target profiles of compounds in MLD can cover most of the biomolecules reported in literature. The MoA of MLD can cover most types of MoA of western drugs for CAG. The treatment of CAG by MLD involved the regulation of various biological functional modules, e.g., inflammation/immune, cell proliferation, cell apoptosis, cell differentiation, digestion and metabolism. Experimental results show that MLD can inhibit cell proliferation, promote cell apoptosis and differentiation, reduce the inflammation level and promote lipid droplet accumulation in MNNG-induced GES-1 cells. CONCLUSION: The network pharmacology framework integrating computational prediction and experimental validation provides a novel way for exploring the MoA of MLD.

10.
J Clin Oncol ; : JCO2101963, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34905388

RESUMO

PURPOSE: Interventional hepatic arterial infusion chemotherapy of infusional fluorouracil, leucovorin, and oxaliplatin (HAIC-FO) displayed an encouraging safety profile and antitumor activity in a previous phase II trial and a propensity-score-matching study involving patients with locally advanced hepatocellular carcinoma (HCC). METHODS: In this open-label, phase III trial, patients with advanced HCC, previously untreated with systemic therapy, were randomly assigned in a 1:1 ratio to receive HAIC-FO or sorafenib. The primary end point was overall survival (OS) in the intention-to-treat population. An exploratory model for predicting the efficacy of HAIC-FO on the basis of genomic sequencing was developed. RESULTS: Between May 2017 and May 2020, 262 patients were randomly assigned. The median tumor size was 11.2 cm (interquartile range, 8.5-13.7 cm). Macrovascular invasion was present in 65.6%, and the percentage of patients with > 50% tumor volume involvement of the liver and/or Vp-4 portal vein tumor thrombosis was 49.2%. At data cutoff (October 31, 2020), median OS was 13.9 months for HAIC-FO and 8.2 for sorafenib (hazard ratio [HR] 0.408; 95% CI, 0.301 to 0.552; P < .001). Tumor downstaging occurred in 16 (12.3% of 130) patients receiving HAIC-FO, including 15 receiving curative surgery or ablation, and finally achieving a median OS of 20.8 months, with a 1-year OS rate of 93.8%. In high-risk subpopulations, OS was significantly longer with HAIC-FO than with sorafenib (10.8 months v 5.7 months; HR 0.343; 95% CI, 0.219 to 0.538; P < .001). A newly developed 15-mutant-gene prediction model identified 83% of patients with response to HAIC-FO. HAIC-FO responders had longer OS than HAIC-FO nonresponders (19.3 months v 10.6 months; HR 0.323; 95% CI, 0.186 to 0.560; P = .002). CONCLUSION: HAIC-FO achieved better survival outcomes than sorafenib in advanced HCC, even in association with a high intrahepatic disease burden.

12.
Nature ; 600(7889): 456-461, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34912090

RESUMO

Commercial chemicals are used extensively across urban centres worldwide1, posing a potential exposure risk to 4.2 billion people2. Harmful chemicals are often assessed on the basis of their environmental persistence, accumulation in biological organisms and toxic properties, under international and national initiatives such as the Stockholm Convention3. However, existing regulatory frameworks rely largely upon knowledge of the properties of the parent chemicals, with minimal consideration given to the products of their transformation in the atmosphere. This is mainly due to a dearth of experimental data, as identifying transformation products in complex mixtures of airborne chemicals is an immense analytical challenge4. Here we develop a new framework-combining laboratory and field experiments, advanced techniques for screening suspect chemicals, and in silico modelling-to assess the risks of airborne chemicals, while accounting for atmospheric chemical reactions. By applying this framework to organophosphate flame retardants, as representative chemicals of emerging concern5, we find that their transformation products are globally distributed across 18 megacities, representing a previously unrecognized exposure risk for the world's urban populations. More importantly, individual transformation products can be more toxic and up to an order-of-magnitude more persistent than the parent chemicals, such that the overall risks associated with the mixture of transformation products are also higher than those of the parent flame retardants. Together our results highlight the need to consider atmospheric transformations when assessing the risks of commercial chemicals.

13.
BMC Cancer ; 21(1): 1347, 2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34923955

RESUMO

BACKGROUND: The accuracy of existing biomarkers for predicting the prognosis of hepatocellular carcinoma (HCC) is not satisfactory. It is necessary to explore biomarkers that can accurately predict the prognosis of HCC. METHODS: In this study, original transcriptome data were downloaded from The Cancer Genome Atlas (TCGA) database. Immune-related long noncoding ribonucleic acids (irlncRNAs) were identified by coexpression analysis, and differentially expressed irlncRNA (DEirlncRNA) pairs were distinguished by univariate analysis. In addition, the least absolute shrinkage and selection operator (LASSO) penalized regression was modified. Next, the cutoff point was determined based on the area under the curve (AUC) and Akaike information criterion (AIC) values of the 5-year receiver operating characteristic (ROC) curve to establish an optimal model for identifying high-risk and low-risk groups of HCC patients. The model was then reassessed in terms of clinicopathological features, survival rate, tumor-infiltrating immune cells, immunosuppressive markers, and chemotherapy efficacy. RESULTS: A total of 1009 pairs of DEirlncRNAs were recognized in this study, 30 of these pairs were included in the Cox regression model for subsequent analysis. After regrouping according to the cutoff point, we could more effectively identify factors such as aggressive clinicopathological features, poor survival outcomes, specific immune cell infiltration status of tumors, high expression level of immunosuppressive biomarkers, and low sensitivity to chemotherapy drugs in HCC patients. CONCLUSIONS: The nonspecific expression level signature involved with irlncRNAs shows promising clinical value in predicting the prognosis of HCC patients.

14.
Zhongguo Zhong Yao Za Zhi ; 46(22): 5773-5780, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34951164

RESUMO

With the widespread application of next-generation sequencing(NGS), especially 16 S rRNA and shotgun sequencing, researchers are no longer troubled with massive data on the gut microbiota, and the correlation between the gut microbiota and the brain(central nervous system) has been gradually revealed. Research on the microbiota-gut-brain axis(MGBA) based on the gut microbiota have provided insights into the exploration of the pathogenesis and risk factors of ischemic stroke(IS), a cerebrovascular disease with high disability and mortality rates, and also facilitate the selection of therapeutic targets of this class of drugs. This study reviewed the application of NGS in the study of gut microbiota and the research progress of MGBA in recent years and systematically collated the research papers on the correlation between IS and gut microbiota. Furthermore, from the bi-directional regulation of MGBA, this study also discussed the high-risk factors of IS under the dysregulation of gut microbiota and the pathophysiological changes of gut microbiota after the occurrence of IS and summarized the related targets to provide a reliable reference for the therapeutic research of IS from the gut microbiota.


Assuntos
Microbioma Gastrointestinal , AVC Isquêmico , Acidente Vascular Cerebral , Encéfalo , Humanos , Acidente Vascular Cerebral/genética
15.
Ecol Lett ; 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-34972253

RESUMO

Elton's biotic resistance hypothesis, which posits that diverse communities should be more resistant to biological invasions, has received considerable experimental support. However, it remains unclear whether such a negative diversity-invasibility relationship would persist under anthropogenic environmental change. By using the common ragweed (Ambrosia artemisiifolia) as a model invader, our 4-year grassland experiment demonstrated consistently negative relationships between resident species diversity and community invasibility, irrespective of nitrogen addition, a result further supported by a meta-analysis. Importantly, our experiment showed that plant diversity consistently resisted invasion simultaneously through increased resident biomass, increased trait dissimilarity among residents, and increased community-weighted means of resource-conservative traits that strongly resist invasion, pointing to the importance of both trait complementarity and sampling effects for invasion resistance even under resource enrichment. Our study provides unique evidence that considering species' functional traits can help further our understanding of biotic resistance to biological invasions in a changing environment.

16.
Nat Mater ; 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34916657

RESUMO

Nanoscale periodic moiré patterns, for example those formed at the interface of a twisted bilayer of two-dimensional materials, provide opportunities for engineering the electronic properties of van der Waals heterostructures1-11. In this work, we synthesized the epitaxial heterostructure of 1T-TiTe2/1T-TiSe2 with various twist angles using molecular beam epitaxy and investigated the moiré pattern induced/enhanced charge density wave (CDW) states with scanning tunnelling microscopy. When the twist angle is near zero degrees, 2 × 2 CDW domains are formed in 1T-TiTe2, separated by 1 × 1 normal state domains, and trapped in the moiré pattern. The formation of the moiré-trapped CDW state is ascribed to the local strain variation due to atomic reconstruction. Furthermore, this CDW state persists at room temperature, suggesting its potential for future CDW-based applications. Such moiré-trapped CDW patterns were not observed at larger twist angles. Our study paves the way for constructing metallic twist van der Waals bilayers and tuning many-body effects via moiré engineering.

17.
J Neuroinflammation ; 18(1): 291, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34920740

RESUMO

BACKGROUND: Stress-induced neuroinflammation was considered to play a critical role in the pathogenesis of depression. Transcutaneous auricular vagus nerve stimulation (taVNS) is a relatively non-invasive alternative treatment for patients suffering from major depressive disorder. The anti-inflammatory signal of vagus nerve is mediated by α7 nicotinic acetylcholine receptor (α7nAchR), and the hippocampus, the region with the most distribution of α7nAchR, regulates emotions. Here, we investigated the role of α7nAchR mediating hippocampal neuroinflammation in taVNS antidepressant effect though homozygous α7nAChR (-/-) gene knockout and α7nAchR antagonist (methyllycaconitine, MLA). METHODS: There were control, model, taVNS, α7nAChR(-/-) + taVNS, hippocampus (Hi) MLA + taVNS and Hi saline + taVNS groups. We used the chronic unpredicted mild stress (CUMS) method to establish depressive model rats for 42 days, excepting control group. After the successful modeling, except the control and model, the rats in the other groups were given taVNS, which was applied through an electroacupuncture apparatus at the auricular concha (2/15 Hz, 2 mA, 30 min/days) for 21 days. Behavioral tests were conducted at baseline, after modeling and after taVNS intervention, including sucrose preference test (SPT), open field test (OFT) and forced swimming test (FST). These tests are widely used to evaluate depression-like behavior in rats. The samples were taken after experiment, the expressions of α7nAchR, NF-κB p65, IL-1ß and the morphology of microglia were detected. RESULTS: Depression-like behavior and hippocampal neuroinflammation in CUMS model rats were manifested by down-regulated expression of α7nAchR, up-regulated expression of NF-κB p65 and IL-1ß, and the morphology of microglia was in amoebic-like activated state. TaVNS could significantly reverse the above-mentioned phenomena, but had rare improvement effect for α7nAChR(-/-) rats and Hi MLA rats. CONCLUSION: The antidepressant effect of taVNS is related to hippocampal α7nAchR/NF-κB signal pathway.

18.
Am Surg ; : 31348211054532, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34743609

RESUMO

Image-guided local thermal ablation (LTA) plays an important role in the treatment of hepatocellular carcinoma (HCC), especially in patients with HCC who are not suitable for hepatectomy. Radiofrequency ablation (RFA) and microwave ablation (MWA) are the most widely used LTA clinically. Radiofrequency ablation can achieve the best result; that is, a similar therapeutic effect as hepatectomy if the tumor ≤3 cm, while MWA can effectively ablate tumors ≤5 cm. Local thermal ablation has an advantage over liver resection in terms of minimally invasive surgery and can achieve a comparable prognosis and efficacy to liver resection. For borderline liver function, selecting LTA as the first-line therapy may bring more benefits to patients with cirrhosis background. In addition, a combination of multiple therapies for HCC is a good choice, such as LTA combined with transcatheter arterial chemoembolization (TACE), which can achieve a better prognosis than single therapy for larger tumors. For patients who are awaiting liver transplantation, LTA is a good choice. The main problem of LTA needed to be solved is to prevent the local tumor recurrence after ablation in patients with HCC.

19.
Nanotechnology ; 33(8)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34731847

RESUMO

2D van der Waals materials are crystals composed of atomic layers, which have atomic thickness scale layers and rich distinct properties, including ultrafast optical response, surface effects, light-mater interaction, small size effects, quantum effects and macro quantum tunnel effects. With the exploration of saturable absorption characteristic of 2D van der Waals materials, a series of potential applications of 2D van der Waals materials as high threshold, broadband and fast response saturable absorbers (SAs) in ultrafast photonics have been proposed and confirmed. Herein, the photoelectric characteristics, nonlinear characteristic measurement technique of 2D van der Waals materials and the preparation technology of SAs are systematically described. Furthermore, the ultrafast pulsed fiber lasers based on classical 2D van der Waals materials including graphene, transition metal chalcogenides, topological insulators and black phosphorus have been fully summarized and analyzed. On this basis, opportunities and directions in this field, as well as the research results of ultrafast pulsed fiber lasers based on the latest 2D van der Waals materials (such as PbO, FePSe3, graphdiyne, bismuthene, Ag2S and MXene etc), are reviewed and summarized.

20.
Adv Mater ; : e2107799, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34818689

RESUMO

Superconducting proximity effect (SPE) induces superconductivity transition in the otherwise non superconducting thin-film in proximity with a superconductor. The SPE usually occurs in real space and decays exponentially with the film thickness. Herein, we unveiled an abnormal SPE in a topological insulator (TI)/superconductor heterostructure, which is attributed to the topologically protected surface state. Surprisingly, such abnormal SPE occurs in momentum space regardless the TI film thickness, as long as the topological surface states are robust and form a continuous conduction loop. Combining transport measurements and scanning tunneling microscopy/spectroscopy techniques, we explored the SPE in Bi2 Se3 /FeSe0.5 Te0.5 heterostructures, where Bi2 Se3 is an ideal three-dimensional topological insulator and FeSe0.5 Te0.5 a typical iron-based superconductor. As the thickness of the Bi2 Se3 thin-film exceeds 400 nanometers, there still exits SPE-induced superconductivity on the surface of Bi2 Se3 thin-film with a transition temperature Tc not less than 10 K. Such an extraordinary behavior is induced by the unique properties of topologically protected surface states of Bi2 Se3 . This research will deepen the understanding of important role of topologically protected surface states in the SPE. This article is protected by copyright. All rights reserved.

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