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1.
J Pharm Biomed Anal ; 177: 112843, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31509788

RESUMO

An UHPLC method was developed for the determination of 15 prenylflavonoids from aerial parts of Epimedium grandiflorum and related species (Berberidaceae). The separation was achieved using a reverse phased column and water/acetonitrile gradient as a mobile phase at a temperature of 40°C. The developed analytical method was validated for linearity, limits of detection (LOD) and limits of quantification (LOQ), stability and repeatability. The LOD and LOQ were found to be in the range from 0.1-0.5 µg/mL and 0.3-1 µg/mL, respectively. The wavelength used for quantification with the photodiode array detector was 269 nm. The total content of 15 prenylflavonoids was 9.1-20.6 mg/g for E. grandiflorum (except for sample #2899 and #20862), 5.6-35.4 mg/g for E. brevicornu and 10.8-30.5 mg/g for E. sagittatum. Twenty dietary supplements contained in the range from 0.1 to 81.7 mg/day. The developed method is simple, rapid and especially suitable for quality assessment of E. grandiflorum and dietary supplements containing E. grandiflorum. Liquid chromatography quadrupole time-of-flight-mass spectrometry (LC-QToF) is described for the identification and confirmation of compounds in plant samples and dietary supplements. This technique is also used for chemical profiling of Epimedium samples. This method involved the use of protonated ions in the positive ion mode and deprotonated ions in the negative ion mode with extracted ion chromatogram (EIC). Chemometric analytical tools for visualizing the plant and commercial samples quality were used for discriminating between Epimedium species and dietary supplements with regards to the relative content or presence of components. A HPTLC method was also developed for the fast chemical fingerprint analysis of Epimedium species.

2.
J Cell Biochem ; 121(1): 557-565, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31338903

RESUMO

Early diagnosis of gastric cancer (GC) is an effective method to improve prognosis. Increasing number of long noncoding RNAs (lncRNAs) have been reported as biomarkers for several cancers. We aim to detect the level of lncRNA B3GALT5-AS1 and its association with clinical parameters and to further explore its application value in GC. We measured serum B3GALT5-AS1 expression in 107 patients with GC, 40 polyp patients, and 87 normal controls to explore the significance of serum B3GALT5-AS1 in GC using the quantitative real-time polymerase chain reaction method. The result demonstrated that B3GALT5-AS1 level was markedly richer in GC patients than that in normal people (P < .001). B3GALT5-AS1 may be served as a diagnostic marker for distinguishing GC patients from healthy people, and the proportion under the receiver operating characteristics curve is 0.816 (95% confidence interval, 0.758-0.874; P = .03). Further exploration validated that high serum B3GALT5-AS1 level was related to TNM stage (P = .024), and lymph node metastasis (P = .023). Our study suggested that serum B3GALT5-AS1 may be employed as an ideal biomarker for early screening of GC.

3.
J Nanosci Nanotechnol ; 20(2): 731-740, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383068

RESUMO

NiO/ZnO gas-sensing nanotube materials were prepared by electrospinning. The structure and morphology of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energydispersive X-ray detection (EDX) and Brunauer-Emmett-Teller (BET) analysis. The template, PAN (peroxyacetyl nitrate) fibers, was completely removed, as evidenced by the EDX results. The final NiO/ZnO composite materials were composed of hexagonal wurtzite ZnO and cubic NiO and exhibited hollow tubular structures. In the composites, p-n heterojunctions were formed at the interface of NiO and ZnO. The results of gas sensitivity tests showed that the incorporation of NiO considerably improved the gas sensitivity of ZnO to ethanol. When the doping ratio was 0.125 mol/mol, the composites exhibited the highest sensitivity to ethanol (100.92 at 300 °C) and showed high selectivity.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31796406

RESUMO

Spatial regularization (SR) is known as an effective tool to alleviate the boundary effect of correlation filter (CF), a successful visual object tracking scheme, from which a number of state-of-the-art visual object trackers can be stemmed. Nevertheless, SR highly increases the optimization complexity of CF and its target-driven nature makes spatially-regularized CF trackers may easily lose the occluded targets or the targets surrounded by other similar objects. In this paper, we propose selective spatial regularization (SSR) for CF-tracking scheme. It can achieve not only higher accuracy and robustness, but also higher speed compared with spatially-regularized CF trackers. Specifically, rather than simply relying on foreground information, we extend the objective function of CF tracking scheme to learn the target-context-regularized filters using target-context-driven weight maps. We then formulate the online selection of these weight maps as a decision making problem by a Markov Decision Process (MDP), where the learning of weight map selection is equivalent to policy learning of the MDP that is solved by a reinforcement learning strategy. Moreover, by adding a special state, representing not-updating filters, in the MDP, we can learn when to skip unnecessary or erroneous filter updating, thus accelerating the online tracking. Finally, the proposed SSR is used to equip three popular spatially-regularized CF trackers to significantly boost their tracking accuracy, while achieving much faster online tracking speed. Besides, extensive experiments on five benchmarks validate the effectiveness of SSR.

5.
JAMA Netw Open ; 2(12): e1916591, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31800066

RESUMO

Importance: The prevalence of depressive symptoms among older adults has become an increasingly important public health priority. Elevated depressive symptoms are well documented among elderly people with cardiovascular disease (CVD), but studies conducted among Chinese adults are scarce. Objective: To estimate the association between depressive symptoms and incident CVD among middle-aged and older Chinese adults. Design, Setting, and Participants: The China Health and Retirement Longitudinal Study is an ongoing nationally representative prospective cohort study that was initiated in 2011. This cohort study included 12 417 middle-aged and older Chinese adults without heart disease and stroke at baseline. Statistical analysis was conducted from April 25, 2018, to December 13, 2018. Exposure: Depressive symptoms were assessed using the validated 10-item of Center for Epidemiologic Studies Depression Scale. Main Outcomes and Measures: Incident CVD (ie, self-reported physician-diagnosed heart disease and stroke combined) was followed-up from June 1, 2011, to June 31, 2015. The Center for Epidemiologic Studies Depression Scale total score ranges from 0 to 30, with a score of 12 or more indicating elevated depressive symptoms. Results: Of the 12 417 participants (mean [SD] age at baseline, 58.40 [9.51] years), 6113 (49.2%) were men. During the 4 years of follow-up, 1088 incident CVD cases were identified. Elevated depressive symptoms were independently associated with an increased CVD risk (adjusted hazard ratio, 1.39; 95% CI, 1.22-1.58) after adjusting for age, sex, residence, marital status, educational level, smoking status, drinking status, systolic blood pressure, and body mass index; history of diabetes, hypertension, dyslipidemia, and chronic kidney disease; and use of hypertension medications, diabetes medications, and lipid-lowering therapy. Of the 10 individual depressive symptoms measured by the Center for Epidemiologic Studies Depression Scale, only 2 symptoms, restless sleep (adjusted hazard ratio, 1.21; 95% CI, 1.06-1.39) and loneliness (adjusted hazard ratio, 1.21; 95% CI, 1.02-1.44), were significantly associated with incident CVD. Conclusions and Relevance: Elevated depressive symptoms overall and 2 individual symptoms (restless sleep and loneliness) were significantly associated with incident CVD among middle-aged and older Chinese adults.

6.
Sci Rep ; 9(1): 18018, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784655

RESUMO

Scientific management of nitrogen (N) fertilizer has a significant effect on yield while also reducing the environmental risks. In this study, we conducted field experiments over three years at two different sites (Zhengzhou and Shangshui) in Henan Province, China, using different N application rates (0, 90,180, 270, and 360 kg ha-1) to determine the relationships between soil N supply and N demand in winter wheat (Triticum aestivum L.). Optimal N input was then determined. Both sites showed the same trend. Namely, aboveground N uptake and soil nitrate N (NO3--N) increased with increasing N, while NO3--N decreased with increasing soil depth, gradually moving downwards with growth. A significant correlation (p < 0.001) between increasing aboveground N uptake and increasing NO3--N was also observed under N application, with the best relationships occurring in the 20-60 cm layer during jointing-anthesis (R2 = 0.402-0.431) and the 20-80 cm layer at maturity (R2 = 0.474). Root weight density showed the same spatial-temporal characteristics as NO3--N, following a unimodal trend with increasing N, and peaking at 90 kg ha-1. The root weight density was mainly distributed in the 0-60 cm layer (above 80%), with the 20-60 cm layer accounting for 30% of the total root system. In this layer, the root weight density was also significantly positively correlated with aboveground N uptake. Wheat yield reached saturation under high N (>270 kg ha-1), with a sharp decrease in N use efficiency (NUE) and linear increase in residual NO3--N. To balance yield and the risk of environmental pollution in the experimental area, an N application rate of 180-270 kg ha-1 is recommended under sufficient irrigation, thereby supporting a well-developed root system while ensuring balance between N supply and demand.

7.
J Bone Miner Res ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31800971

RESUMO

Duchenne Muscular Dystrophy (DMD) is the most common muscular dystrophy seen in children. In addition to skeletal muscle, DMD also has a significant impact on bone. The pathogenesis of bone abnormalities in DMD is still unknown. Recently, we have identified a novel bone-regulating cytokine, fibroblast growth factor-21 (FGF-21), which is dramatically upregulated in skeletal muscles from DMD animal models. We hypothesize that muscle-derived FGF-21 negatively affects bone homeostasis in DMD. Dystrophin/utrophin double-knockout (dKO) mice were used in this study. We found the levels of circulating FGF-21 were significantly higher in dKO mice than in age-matched WT controls. Further tests on FGF-21 expressing tissues revealed that both FGF-21 mRNA and protein expression were dramatically upregulated in dystrophic skeletal muscles, while FGF-21 mRNA expression was downregulated in liver and white adipose tissue (WAT) compared to WT controls. Neutralization of circulating FGF-21 by IP injection of anti-FGF-21 antibody significantly alleviated progressive bone loss in weight-bearing (vertebra, femur and tibia) and non-weight bearing bones (parietal bones) in dKO mice. We also found that FGF-21 directly promoted RANKL induced osteoclastogenesis from bone marrow macrophages (BMMs), as well as promoted adipogenesis while concomitantly inhibiting osteogenesis of bone marrow mesenchymal stem cells (BMMSCs). Furthermore, fibroblast growth factor receptors (FGFRs) and co-receptor ß-klotho (KLB) were expressed in bone cells (BMM derived osteoclasts and BMMSCs) and bone tissues. KLB knockdown by siRNAs significantly inhibited the effects of FGF21 on osteoclast formation of BMMSs and on adipogenic differentiation of BMMSCs, indicating that FGF-21 may directly affect dystrophic bone via FGFRs-ß-klotho complex. In conclusion, this study demonstrates that dystrophic skeletal muscles express and secrete significant levels of FGF-21, which negatively regulates bone homeostasis and represents an important pathological factor for the development of bone abnormalities in DMD. The current study highlights the importance of muscle/bone cross talk via muscle derived factors (myokines) in the pathogenesis of bone abnormalities in DMD. This article is protected by copyright. All rights reserved.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31711666

RESUMO

Water scarcity is becoming increasingly worse in the world. To address water shortages, the water supply needs to be supplemented. In arid regions, flora and fauna use fog or the moisture in air as a source of water. An important consideration in efficient water collection is transport of water droplets collected as rapidly as possible to storage/use before they are evaporated. Wettability gradient on a surface is expected to increase the rate of transportation. In this study, a bioinspired triangular surface with multistep wettability gradient was fabricated. Water condensation and transport studies were carried out on triangular surfaces with wettability gradient in ambient air. Wettability gradient is found to accelerate the water transport. The droplets can climb even if a surface is mounted on an inclined plane.

9.
Glia ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31721324

RESUMO

Schwann cell, the major glial cell in the peripheral nervous system, plays an essential role in peripheral nerve regeneration. However, the regulation of Schwann cell behavior following nerve injury is insufficiently explored. According to the development of high-throughput techniques, long noncoding RNAs (lncRNAs) have been recognized. Accumulating evidence shows that lncRNAs take part in diverse biological processes and diseases. Here, by microarray analysis, we identified an upregulated lncRNA profile following sciatic nerve injury and focused on BC088259 for further investigation. Silencing or overexpression of BC088259 could affect Schwann cell migration. Mechanistically, BC088259 might exert this regulatory role by directly binding with Vimentin. Collectively, our study not only revealed a set of upregulated lncRNAs following nerve injury but also identified a new functional lncRNA, BC088259, which was important for Schwann cell migration, providing a therapeutic avenue toward peripheral nerve injury.

10.
Can Respir J ; 2019: 7930396, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781316

RESUMO

Background: Imbalanced oxidative stress and antioxidant defense are involved in airway remodeling in asthma. It has been demonstrated that Tetrandrine has a potent role in antioxidant defense in rheumatoid arthritis and hypertension. However, the correlation between Tetrandrine and oxidative stress in asthma is utterly blurry. This study aimed to investigate the role of Tetrandrine on oxidative stress-mediated airway remolding. Materials and Methods: Chronic asthma was established by ovalbumin (OVA) administration in male Wistar rats. Histopathology was determined by HE staining. Immunofluorescence was employed to detect the expression of α-SMA and Nrf-2. Level of oxidative stress and matrix metalloproteinases were examined by ELISA kits. Cell viability and cell cycle of primary airway smooth muscle cells (ASMCs) were evaluated by CCK8 and flow cytometry, respectively. Signal molecules were detected using western blot. Results: Tetrandrine effectively impairs OVA-induced airway inflammatory and airway remodeling by inhibiting the expression of CysLT1 and CysLTR1. The increase of oxidative stress and subsequent enhancement of MMP9 and TGF-ß1 expression were rescued by the administration of Tetrandrine in the rat model of asthma. In in vitro experiments, Tetrandrine markedly suppressed TGF-ß1-evoked cell viability and cell cycle promotion of ASMCs in a dose-dependent manner. Furthermore, Tetrandrine promoted Nrf-2 nuclear transcription and activated its downstream HO-1 in vivo and in vitro. Conclusion: Tetrandrine attenuates airway inflammatory and airway remodeling in rat model of asthma and TGF-ß1-induced cell proliferation of ASMCs by regulating oxidative stress in primary ASMCs, suggesting that Tetrandrine possibly is an effective candidate therapy for asthma.

11.
Eur J Pharmacol ; : 172823, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31770525

RESUMO

Leukotriene B4 (LTB4) has been found to contribute to pulmonary arterial smooth muscle cells (PASMCs) proliferation and pulmonary arterial remodeling therefore the development of pulmonary arterial hypertension (PAH). Yet, the underlying molecular mechanisms remain poorly understood. The present study aims to address this issue. Our results demonstrate that LTB4 dose- and time-dependently induced proliferation of primary cultured rat PASMCs, this was accompanied with the activation of phosphatidylinositol-3-kinase/Akt (PI3K/Akt) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathways, and consequent inactivation of glycogen synthase kinase-3ß (GSK-3ß), up-regulation of ß-catenin and induction of cyclin D1 expression. The presence of PI3K inhibitor (LY294002) or MEK inhibitor (U0126) or prior silencing of ß-catenin with siRNA suppressed LTB4-induced cyclin D1 up-regulation and PASMCs proliferation. In addition, inactivation or lack of GSK-3ß up-regulated ß-catenin and cyclin D1 in PASMCs. Taken together, our study indicates that activation of PI3K/Akt and ERK1/2 pathways mediates LTB4-induced PASMCs proliferation by modulating GSK-3ß/ß-catenin/cyclin D1 axis and suggests that targeting this pathway might have potential value in alleviating vascular remodeling and benefit PAH.

12.
Zootaxa ; 4679(2): zootaxa.4679.2.8, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31715963

RESUMO

Two new species of the genus Pogaina Marcus, 1954 (Provorticidae), namely Pogaina sinensis n. sp. and Pogaina shenzhenensis n. sp. are described from brackish water in the intertidal zone of Shenzhen Bay. For P. sinensis n. sp., the tubular stylet is slightly curved at the distal end and a fusiform structure with a flange is present at 66% of the stylet. The flange encircles the stylet, with its ends attached to the midpoint and the distal end of the stylet. For P. shenzhenensis n. sp., the stylet has a N-shaped overall morphology. A band provided with dense needle-like structures is present at the distal end of the stylet. Both the morphological (stylet) and phylogenetic (18S rDNA and 28S rDNA) analyses support the establishment of these two new species.


Assuntos
Platelmintos , Animais , China , DNA Ribossômico , Filogenia , Águas Salinas
13.
Cell Death Dis ; 10(11): 829, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685807

RESUMO

Metastasis is a well-known poor prognostic factor in cancer. However, the mechanisms how long non-coding RNAs (lncRNAs) regulate metastasis in colorectal cancer (CRC) remain largely unknown. Besides, tumor-associated macrophages (TAMs) play an important role in tumor progression, yet the contribution of lncRNA-mediated crosstalk between TAMs and CRC cells to tumor progression is not well understood. In this study, we report that lncRNA RPPH1 was significantly upregulated in CRC tissues, and the RPPH1 overexpression was associated with advanced TNM stages and poor prognosis. RPPH1 was found to promote CRC metastasis in vitro and in vivo. Mechanistically, RPPH1 induced epithelial-mesenchymal transition (EMT) of CRC cells via interacting with ß-III tubulin (TUBB3) to prevent its ubiquitination. Furthermore, CRC cell-derived exosomes transported RPPH1 into macrophages which mediate macrophage M2 polarization, thereby in turn promoting metastasis and proliferation of CRC cells. In addition, exosomal RPPH1 levels in blood plasma turned out to be higher in treatment-naive CRC patients but lower after tumor resection. Compared to CEA and CA199, exosomal RPPH1 in CRC plasma displayed a better diagnostic value (AUC = 0.86). Collectively, RPPH1 serves as a potential therapeutic and diagnostic target in CRC.

14.
Nat Prod Res ; : 1-8, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746227

RESUMO

Two new phenylpropanoids, named (2'R*,3'R*)-2',3'-dihydroxy-4'-methoxy-caffeoyl butyrate (1), 9-acetoxy syringin (2), and a new dihydrostilbene, named (8'R)-4',5-dihydroxy-4,8'-dimethoxy-2-hydroxyethyl diphenylethane (3), together with five analogues (4-8), were isolated from the flower buds of Magnolia biondii Pamp. Their structures were elucidated by extensive spectroscopic analyses and comparison with literature data. The absolute configurations were deduced by comparison of experimental and calculated gauge-independent atomic orbital (GIAO) 1 D NMR data. Moreover, the isolated compounds (1-8) were evaluated in vitro for their acetylcholinesterase (AChE) inhibitory activities.

15.
Zootaxa ; 4695(4): zootaxa.4695.4.3, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31719341

RESUMO

Two new species of Rhabdocoela, namely Alcha sinensis n. sp. (Polycystididae) and Trigonostomum sinensis n. sp. (Trigonostomidae), were discovered from the intertidal zone of eastern Shenzhen City, China. For A. sinensis n. sp., the stylet consists of two symmetrical triangular plates and one lamellar plate. All three plates are jagged at their posterior ends. The anterior end of the stylet connects to a thick muscular layer, which causes its movement. For T. sinensis n. sp., the copulatory organ consists of a long-tubular stylet and two "T"-shaped plates (plate I and plate II). The stylet bends 120° at 25% of its length from the base and extends straight distally. Two "T" plates are connected to each other and surround the stylet. Plate I is hook-shaped at its distal end, and plate II has a similar length but only half the width of plate I. The phylogenetic (18S rDNA and 28S rDNA) results also support the establishment of these two new species. On the basis of the molecular phylogeny and morphology of the copulatory organ and bursa appendage, we propose a new categorization of the species of Trigonostomum.


Assuntos
Besouros , Platelmintos , Animais , China , DNA Ribossômico , Filogenia
16.
Food Chem ; : 125695, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31704070

RESUMO

Developing food structures that combine material properties from two or three components is intriguing as well as challenging. This study reports a simple technique for co-solvation of two hydrophobic biopolymers in a neutral aqueous solution. The process suspended rice proteins (RPs) and shellac at pH 12 with a one-step adjustment to pH 7. Results from scanning electron microscopy, polyacrylamide gel electrophoresis, and fluorescence studies showed that shellac-RP complexes (SRPs) nucleated through hydrophobic attractions between the two biopolymers. As a result, the refolding of the backbones of RPs was resisted, leading to formation of spherical SRPs with less compactness and larger sizes than untreated RPs. The nanoscale spheres were induced with Ca2+ to structural transition to ribbons or networks. The tunable structures were used to entrap and deliver apigenin for improved, controllable cellular uptake in a HepG-2 cell model compared with free apigenin.

17.
IEEE Trans Pattern Anal Mach Intell ; 41(12): 2791-2806, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31689178

RESUMO

This paper studies active relocalization of 6D camera pose from a single reference image, a new and challenging problem in computer vision and robotics. Straightforward active camera relocalization (ACR) is a tricky and expensive task that requires elaborate hand-eye calibration on precision robotic platforms. In this paper, we show that high-quality camera relocalization can be achieved in an active and much easier way. We propose a hand-eye calibration free approach to actively relocating the camera to the same 6D pose that produces the input reference image. We theoretically prove that, given bounded unknown hand-eye pose displacement, this approach is able to rapidly reduce both 3D relative rotational and translational pose between current camera and the reference one to an identical matrix and a zero vector, respectively. Based on these findings, we develop an effective ACR algorithm with fast convergence rate, reliable accuracy and robustness. Extensive experiments validate the effectiveness and feasibility of our approach on both laboratory tests and challenging real-world applications in fine-grained change monitoring of cultural heritages.

18.
Nat Prod Res ; : 1-8, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674834

RESUMO

Investigation into the chemical diversity of Artemisia argyi led to the discovery of two new (1, 4) and four known (2-3, 5-6) sesquiterpenoids. The new structures were determined via extensive spectroscopic data, including IR, UV, MS, and NMR, and the absolute configurations of these compounds were elucidated by calculated ECD method. All isolates were tested for their inhibitory activity against NO production in RAW 264.7 macrophages, and the isolated sesquiterpenoids exhibited NO production inhibitory activity with IC50 values ranging from 1.91 to 36.52 µM.

19.
Nat Prod Res ; : 1-8, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31680553

RESUMO

Two new norsesquiterpenoids, dioscopposin A (1) and dioscopposin B (2), as well as 21 known compounds (3-23) were isolated from the stems and leaves of Dioscorea oppositifolia L. Their structures were elucidated by detailed analysis of comprehensive spectroscopic data. The absolute configurations were deduced by the comparison of experimental and calculated electronic circular dichroism spectra. Estrogenic activity of all the isolated compounds were evaluated using MCF-7 cells proliferation assay and compounds 2, 3, 7, 13, 15, 16, 18 and 21 exhibited proliferation activity.

20.
Nanotechnology ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31770747

RESUMO

Multilayer Te nanosheets have attracted increasing attention due to its high-performance electronic transport properties and good air-stability. Theoretical simulation suggests that electronic properties of multilayer Te nanosheets could be effectively modulated by contact engineering, but most studies have reported p-type multilayer Te devices. Here, for the first time, we report a high performance ambipolar multilayer Te filed-effect-transistors (FETs) with low work function scandium (Sc, 3.58 eV), demonstrating high mobilities of 489 and 648 cm2V-1s-1 for electron and hole transport, respectively. Multilayer Te FETs with large work function metals, such as chromium (Cr, 4.5 eV), show a typical p-type transport behavior. The band structure of multilayer Te with a small bandgap and low work function Sc result in small contact resistance (Rc) for both of electron and hole transport, which leads to the ambipolar behavior of multilayer Te nanosheets. The ambipolar behavior of multilayer Te FETs indicates that contact engineering is a valid tool to tune the electrical properties of multilayer Te and raises a possibility for designing digital circuits based on multilayer Te.

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