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Spin injection, transport, and detection across the interface between a ferromagnet and a spin-carrying channel are crucial for energy-efficient spin logic devices. However, interfacial conductance mismatch, spin dephasing, and inefficient spin-to-charge conversion significantly reduce the efficiency of these processes. In this study, it is demonstrated that an all van der Waals heterostructure consisting of a ferromagnet (Fe3GeTe2) and Weyl semimetal enables a large spin readout efficiency. Specifically, a nonlocal spin readout signal of 150 mΩ and a local spin readout signal of 7.8 Ω is achieved, which reach the signal level useful for practical spintronic devices. The remarkable spin readout signal is attributed to suppressed spin dephasing channels at the vdW interfaces, long spin diffusion, and efficient charge-spin interconversion in Td-MoTe2. These findings highlight the potential of vdW heterostructures for spin Hall effect-enabled spin detection with high efficiency, opening up new possibilities for spin-orbit logic devices using vdW interfaces.
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A Citrus sinensis R2R3 MYB transcription factor (CsMYB96) has previously been shown to be strongly associated with the expression of many genes related to wax biosynthesis in the fruit. In this study, CsMYB96 was found to alleviate water loss by simultaneously regulating the expression of genes encoding plasma membrane intrinsic proteins (CsPIPs) and wax-related genes. Expression profiling indicated that CsPIP1;1 and CsPIP2;4 had high expression that was representative of other aquaporins, and they were down-regulated in the peel of post-harvest citrus fruit. CsPIP2;4 was further characterized as the predominant CsPIP, with high expression and high-water channel activity. Transient overexpression of CsPIP2;4 accelerated water loss in citrus fruit. In silico analysis further indicated that the expression of CsMYB96 had a significant negative correlation with that of CsPIPs. In vivo and in vitro experiments confirmed that CsMYB96 was able to directly repress the expression of CsPIPs. In addition, CsMYB96 was able to activate wax-related genes and promote wax biosynthesis for defense against water loss. Transient and stable overexpression of CsMYB96 reduced water loss from both citrus fruit and Arabidopsis.
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Citrus sinensis , Proteínas de Plantas , Fatores de Transcrição , Perda Insensível de Água , Ceras , Aquaporinas/metabolismo , Citrus sinensis/genética , Citrus sinensis/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Água/metabolismo , Perda Insensível de Água/genética , Ceras/metabolismoRESUMO
KEY MESSAGE: CitWRKY28 and CitNAC029 are involved in cuticular wax synthesis as indicated by the comparative analysis of fruit aliphatic wax content between Citrus reticulata and Citrus trifoliata and gene co-expression analysis. Cuticular wax covers the fruit surface, playing important roles in reduction of fruit water loss and resistance to pathogen invasion. However, there is limited research on the synthesis and transcriptional regulation of cuticular wax in citrus fruit. In this study, we characterized the variations of aliphatic wax in HJ (Citrus reticulata) and ZK (Citrus trifoliata) from young fruit to mature fruit, as well as performed transcriptome sequencing on 27 samples at different fruit developmental stages. The results revealed that the ZK fruit always had a higher aliphatic wax content than the HJ fruit during development. qRT-PCR analysis demonstrated that two KCS genes, CitKCS1 and CitKCS12, had the most significant difference in expression between HJ and ZK. Furthermore, a heterologous expression assay in Arabidopsis indicated that CitKCS1 and CitKCS12 are involved in cuticular wax synthesis. Subsequently, gene co-expression network analysis screened CitWRKY28 and CitNAC029. Dual luciferase and EMSA assays indicated that CitWRKY28 might bind to the promoter of CitKCS1 and CitKCS12 and CitNAC029 might bind to that of CitKCS1 to activate their expression. Moreover, CitWRKY28 and CitNAC029 could promote the accumulation of cuticular wax in Arabidopsis leaves. Our findings provide new insights into the synthesis and regulation of cuticular wax and valuable information for further mining of wax-related genes in citrus fruit.
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Arabidopsis , Citrus , Arabidopsis/genética , Arabidopsis/metabolismo , Citrus/genética , Citrus/metabolismo , Frutas/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ceras/metabolismoRESUMO
Architectural design of hollow carbon spheres (HCSs) plays a vital role in improving their performance and expanding applications. The tailorable synthesis of bumpy or asymmetric HCSs with a refined structure remains a challenge. Herein, bumpy HCSs (BHCSs) and bumpy concave HCSs (BCHCSs) have been engineered. The synthesis involves the formation of a core/shell precursor via the surface polymerization of pyrrole monomers on polystyrene nanoparticles, followed by the controlled pyrolysis process under different conditions. In comparison with HCSs, the concave hollow structure can reduce the excessive interior cavity and maintain prevalent merits of hollow structures; the bumpy shell can improve the surface area and number of active sites, thus improving the kinetics as energy storage devices. As a result, among BCHCSs, BHCSs, and HCSs, BCHCSs exhibit optimal electrochemical performance. The lithium-ion hybrid capacitors employing BCHCSs as an anode can deliver an energy density of 0.2182 kW h kg-1 at a power density of 0.2235 kW kg-1. Overall, this study provides an innovative design and strategy for constructing unique carbon nano-architectures for energy storage.
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All inorganic perovskite nanocrystals CsPbX3(X = Cl, Br, I) are the great potential candidates for the application of high-performance light emitting diodes (LED) due to their high Photoluminescence Quantum Yield (PLQY), high defect tolerance, narrow full-width half-maximum and tunable wavelength of 410-700 nm. However, the application of red-emitting (630-650 nm) CsPbBrxI3-xnanocrystals are perplexed by phase segregation due to the composition of mixed halides and the difference in halide ion mobility. Herein, we provide an effective strategy to suppressing the migration of Br/I ions through Ni2+doping via a facile Hot-Injection method and the PLQY was improved as well. DFT calculations show that the introduction of Ni2+causes a slight contraction of the host crystal structure, which improves the bond energy between Pb and halides and reduces the level of surface defects. Therefore, the phase stability is improved by Ni2+doping because the phase segregation caused by ion migration in the mixed phase is effectively inhibited. Meanwhile, the non-radiative recombination in the exciton transition process is reduced and the PLQY is improved. What's more, benefiting from the suppressed ion migration and enhanced PLQY, we combine the Ni2+-doped CsPbBrxI3-xnanocrystals with different Br/I ratios and YAG: Ce3+phosphors as color conversion layers to fabricate high efficiency WLED. When the ratio of Br/I is 9:11, WLED has a color coordinate of (0.3621, 0.3458), the color temperature of 4336 K and presents a high luminous efficiency of 113.20 lm W-1, color rendering index of 94.9 under the driving current of 20 mA and exhibits excellent stability, which shows great potential in the application of LED.
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BACKGROUND: It's necessary to analyze the role of VEGF, apelin, and HO-1 in patients with type 2 diabetes (T2DM), and to evaluate its relevance to diabetic retinopathy (DR). METHODS: T2DM patients who were treated in our hospital from December 1, 2018 to November 30, 2019 were included. T2DM patients were divided into non-DR (NDR) group, non-proliferative DR (NPDR) group, and proliferative DR (PDR) group. and healthy participants were selected as the control group. The value of VEGF, apelin, and HO1 in predicting PDR were analyzed by receiver operating characteristic (ROC) curve, and the relations of VEGF, apelin, HO-1 and clinical factors in PDR patients were analyzed by Pearson correlation analysis. RESULTS: A total of 295 participants were included. The level of FPG and HbAlc in PDR group were significantly higher than that of other groups (all p < 0.05); the level of VEGF and apelin in PDR group were significantly higher than that of other groups (all p < 0.05), but the level of HO-1 in PDR group were significantly less than that of other groups(p = 0.017); the AUC of VEGF, apelin, HO-1 and combined use was 0.806(95%CI: 0.779-0.861), 0.819(95%CI: 0.765-0.878), 0.808(95%CI: 0.733-0.869) and 0.902(95%CI: 0.822-0.958) respectively, the AUC, sensitivity, specificity of the three combined use was significantly higher than that of single VEGF, apelin, HO-1 use(all p < 0.05). The cutoff values of serum VEGF, apelin, and HO-1 levels for predicting PDR were 163.85 pg/ml, 8.27 ng/ml, and 26.06 mmol/L respectively. Serum VEGF, apelin, and HO-1 in patients with PDR was related to the time course of DM, FPG and HbAlc (all p < 0.05). CONCLUSIONS: VEGF, apelin and HO-1 are related to the progress of DR, and the combined use of VEGF, apelin and HO-1 is beneficial to the diagnosis and treatment of PDR.
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Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Apelina , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/diagnóstico , Heme Oxigenase-1 , Humanos , Curva ROC , Fator A de Crescimento do Endotélio VascularRESUMO
AIM: Gitelman syndrome (GS) is a rare inherited salt-losing renal tubulopathy. Data on clinical features and the pregnancy outcome for female GS patients in a large cohort are lacking. The study was aimed to explore the phenotype and pregnant issue for female GS patients. METHODS: GS cases from the National Rare Diseases Registry System of China (NRSC) were collected, and detailed clinical, laboratory and genetic data were analysed. Articles on pregnancy in GS were also systemically reviewed. RESULTS: A total of 101 GS patients were included; among them, 42.6% were female and 79.2% showed hypomagnesaemia. A lower proportion of female patients presented before 18 years of age, with less frequently reported polyuria, higher serum potassium and less urine sodium and chloride excretions. There was no gender difference in the sodium-chloride cotransporter (NCC) dysfunction evaluated by hydrochlorothiazide test. Twelve of the 43 female GS patients delivered after disease symptom onset, and their pregnancies were generally uneventful. As a group, pregnant GS patients had lower potassium levels in the first-trimester (P = .002) requiring higher potassium supplementation. After delivery, serum potassium (P = .02) and magnesium (P = .03) increased significantly. Both caesarean section and vaginal delivery were safe. CONCLUSION: Female GS patients may have a less severe phenotype with generally favourable outcomes of pregnancy. Intensive monitoring and increased potassium supplementation are necessary during pregnancy, especially in the first-trimester.
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Parto Obstétrico , Síndrome de Gitelman , Potássio , Complicações na Gravidez , Membro 3 da Família 12 de Carreador de Soluto/genética , Desequilíbrio Hidroeletrolítico , Adulto , China/epidemiologia , Cloretos/urina , Parto Obstétrico/métodos , Parto Obstétrico/estatística & dados numéricos , Feminino , Síndrome de Gitelman/epidemiologia , Síndrome de Gitelman/genética , Síndrome de Gitelman/fisiopatologia , Síndrome de Gitelman/terapia , Humanos , Recém-Nascido , Magnésio/sangue , Masculino , Mutação , Poliúria/diagnóstico , Poliúria/etiologia , Potássio/sangue , Potássio/uso terapêutico , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/etiologia , Complicações na Gravidez/fisiopatologia , Complicações na Gravidez/terapia , Resultado da Gravidez/epidemiologia , Eliminação Renal/genética , Sódio/urina , Membro 3 da Família 12 de Carreador de Soluto/metabolismo , Desequilíbrio Hidroeletrolítico/sangue , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/terapia , Desequilíbrio Hidroeletrolítico/urinaRESUMO
WHAT IS KNOWN AND OBJECTIVES: Caffeine citrate is a commonly used methylxanthine for pharmacologic treatment of apnea of prematurity. The aim of this study was to develop and verify a population pharmacokinetic (PPK) model, which can provide a reference for individualized caffeine citrate treatment of apnea in Chinese premature infants. METHODS: A total of 88 serum concentration measurements from 46 preterm patients (median gestational age 29 weeks) were retrospectively collected and the relevant clinical data of patients were recorded. The PPK analysis was performed by non-linear mixed-effect modelling method using NONMEM. Allometric scaling was applied in the PPK analysis, and the final model was evaluated by graphic and statistical methods, including goodness-of-fit plots, normalized prediction distribution errors plots and bootstrap procedures. RESULTS: A one-compartment model with first-order elimination was successfully fitted to the data. The typical scaled values for the parameters clearance and volume of distribution (V) were 0.268 L/h and 109 L per 70 kg, respectively. The weight at the time of blood collection (CW) and post-natal age were identified as important predictors for pharmacokinetic parameters of caffeine. The evaluation process showed good stability and predictability of the final PPK model. WHAT IS NEW AND CONCLUSION: This is a complete PPK study of caffeine citrate in Chinese premature infants with apnea, which complements caffeine pharmacokinetic data of the premature from China. A final PPK model was developed which may serve as a beneficial tool for the use of caffeine citrate in the treatment of apnea in Chinese preterm infants.
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Apneia/tratamento farmacológico , Cafeína/farmacocinética , Estimulantes do Sistema Nervoso Central/farmacocinética , Citratos/farmacocinética , Modelos Biológicos , Povo Asiático , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Citratos/administração & dosagem , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/tratamento farmacológico , Masculino , Dinâmica não Linear , Estudos RetrospectivosRESUMO
Equivalence ratio is one of the most significant parameters in combustion flow fields. In this paper, femtosecond laser-induced plasma spectroscopy (FLIPS) technique for instantaneous one-dimensional local equivalence ratio measurements were performed. By measuring the spatially resolved spectra of FLIPS, we found that the spectral peak area ratios of CH (431 nm)/N2 (337 nm), CH (431 nm)/N2 (357 nm), and CH (431 nm)/O (777 nm) can be utilized to achieve one-dimensional local equivalence ratio measurements. Among them, the CH peak at ~431 nm and the O peak at ~777 nm are strong enough to be used to achieve single-shot measurements, which is important to turbulent flow fields. Furthermore, systematic experiments were performed by using FLIPS in both laminar and turbulent flow fields. The FLIPS technique features the abilities of instantaneous one-dimensional quantitative measurements, high spatial resolution, and no Bremsstrahlung interference.
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We demonstrate the enhancement of femtosecond (fs) laser-induced filaments in air and nitrogen flow fields using a nanosecond (ns) laser. With the ns laser being imposed on the filaments, the length and the emission intensity of the filaments were largely increased. Temporally resolved spectra of the enhanced filaments were obtained. The results show that the ns laser enhanced the short-lifetime fluorescence of nitrogen, which comes from the transition processes of N2 +(B2Σu + - X2Σg +), N2(B3Ðg - A3Σu +) and N2(C3Ðu - B3Ðg). However, it had little effect on the long-lifetime chemiluminescence, which mainly comes from reactions such as N2(A3Σu +) + N2(A3Σu +) â N2(X1Σg +, v = 0) + N2(B3Ðg). A possible explanation of this phenomenon is given, and this phenomenon might have potential applications in instantaneous one-dimensional measurements of various species in gas flow fields.
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There is now the opportunity for nanomaterials to be utilized in bioapplications with low toxicity, good stability and fine dissolvability. Herein, we present a pulsed laser assisted carbon coating method for nanocrystals, and gadolinium carbide/carbon shell (GC/CS) dots with a face-centered cubic structured gadolinium carbide core that have been synthesized in toluene. Good stability of the GC/CS dots was observed, not only in ethanol but also in the immunoconjugates. The MTT assay revealed immunoconjugates with non/low cytotoxicities. As a type of paramagnetic species, the GC/CS dots revealed excellent enhancement in magnetic resonance imaging at a high magnetic field of 14.1 T at ultra-low concentrations. In terms of the relaxivity values of the 1-3 nm GC/CS sample, both [Formula: see text] and [Formula: see text] have been dramatically increased to 86.5 mM-1 s-1 and 107.3 mM-1 s-1, respectively, thereby demonstrating the great potential for GC/CS dots to be utilized as advanced magnetic resonance agents for the diagnosis of cancers.
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Carbonaceous nanotubes (CTs) represent one of the most popular and effective carbon electrode materials for supercapacitors, but the electrochemistry performance of CTs is largely limited by their relatively low specific surface area, insufficient usage of intratube cavity, low content of heteroatom, and poor porosity. An emerging strategy for circumventing these issues is to design novel porous CT-based nanostructures. Herein, a spheres-in-tube nanostructure with hierarchical porosity is successfully engineered, by encapsulating heteroatom-doping hollow carbon spheres into one carbonaceous nanotube (HCSs@CT). This intriguing nanoarchitecture integrates the merits of large specific surface area, good porosity, and high content of heteroatoms, which synergistically facilitates the transportation and exchange of ions and electrons. Accordingly, the as-prepared HCSs@CTs possess outstanding performances as electrode materials of supercapacitors, including superior capacitance to that of CTs, HCSs, and their mixtures, coupled with excellent cycling life, demonstrating great potential for applications in energy storage.
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Inorganic perovskites with special semiconducting properties and structures have attracted great attention and are regarded as next generation candidates for optoelectronic devices. Herein, using a physical vapor deposition process with a controlled excess of PbBr2 , dual-phase all-inorganic perovskite composite CsPbBr3 -CsPb2 Br5 thin films are prepared as light-harvesting layers and incorporated in a photodetector (PD). The PD has a high responsivity and detectivity of 0.375 A W-1 and 1011 Jones, respectively, and a fast response time (from 10% to 90% of the maximum photocurrent) of ≈280 µs/640 µs. The device also shows an excellent stability in air for more than 65 d without encapsulation. Tetragonal CsPb2 Br5 provides satisfactory passivation to reduce the recombination of the charge carriers, and with its lower free energy, it enhances the stability of the inorganic perovskite devices. Remarkably, the same inorganic perovskite photodetector is also highly flexible and exhibits an exceptional bending performance (>1000 cycles). These results highlight the great potential of dual-phase inorganic perovskite films in the development of optoelectronic devices, especially for flexible device applications.
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We demonstrate a non-contact spatiotemporally resolved comprehensive method for gas flow velocity field measurement: Filamentary Anemometry using femtosecond Laser-extended Electric Discharge (FALED). A faint thin plasma channel was generated in ambient air by focusing an 800-nm laser beam of 45 fs, which was used to ignite a pulsed electric discharge between two electrodes separated over 10 mm. The power supplier provided a maximum voltage up to 5 kV and was operated at a burst mode with a current duration of less than 20 ns and a pulse-to-pulse separation of 40 µs. The laser-guided thin filamentary discharge plasma column was blowing up perpendicularly by an air jet placed beneath in-between the two electrodes. Although the discharge pulse was short, the conductivity of the plasma channel was observed to sustain much longer, so that a sequence of discharge filaments was generated as the plasma channel being blown up by the jet flow. The sequential bright thin discharge filaments can be photographed using a household camera to calculate the flow velocity distribution of the jet flow. For a direct comparison, a flow field measurement using FLEET [Appl. Opt. 50, 5158 (2011)] was also performed. The results indicate that the FALED technique can provide instantaneous nonintrusive flow field velocity measurement with good accuracy.
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Epithelial-mesenchymal transition (EMT) plays a pivotal role in the development of cancer. Has-miR-200b-3p is generally recognized as one of the fundamental regulators of EMT. In this study, we found that the expression of miR-200b-3p was downregulated in glioma tissues and human glioma cells U87 and U251. Meanwhile, Up-regulating miR-200b-3p enhanced E-cadherin, reduced mesenchymal markers, and decreased cell proliferation, migration, and invasion in vitro. In vivo, the xenograft mouse model also unveiled the suppressive effects of miR-200b-3p on tumor growth. Additionally, The extracellular-regulated protein kinase 5 (ERK5) was confirmed as a direct target gene of miR-200b-3p. The direct suppression of ERK5 expressions by miR-200b-3p was revealed by luciferase reporter assay, quantitative RT-PCR analysis, and western blot. Moreover, we observed an inverse correlation between miR-200b-3p and ERK5 in human glioma tissues. In summary, our ï¬ndings demonstrated that miR-200b-3p suppresses glioma tumor growth, invasion, and reverses EMT through downregulated its target ERK5.
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Neoplasias Encefálicas/patologia , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Glioma/patologia , MicroRNAs/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/genética , Animais , Sequência de Bases , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Células HEK293 , Humanos , Camundongos SCID , MicroRNAs/genética , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Invasividade NeoplásicaRESUMO
c2D transition metal dichalcogenides (TMDCs)-based heterostructures have been demonstrated to achieve superior light absorption and photovoltaic effects theoretically and experimentally, making them extremely attractive for realizing optoelectronic devices. In this work, a vertical multilayered n-MoS2/n-silicon homotype heterojunction is fabricated, which takes advantage of multilayered MoS2 grown in situ directly on plane silicon. Electrical characterization reveals that the resultant device exhibits high sensitivity to visible-near-infrared light with responsivity up to 11.9 A W(-1). Notably, the photodetector shows high-speed response time of ≈ 30.5 µs/71.6 µs and capability to work under higher pulsed light irradiation approaching 100 kHz. The high response speed could be attributed to a good quality of the multilayer MoS2 , as well as in situ device fabrication process. These findings suggest that the multilayered MoS2 /Si homotype heterojunction have great potential application in the field of visible-near-infrared detection and might be used as elements for construction of high-speed integrated optoelectronic sensor circuitry.
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A novel type of aqueous fluorescent carbon dot (CD) was synthesized using citric acid as the only carbon source via an ammonium hydroxide modulated method, providing a blue color gamut. The amino group is considered to be the key factor in the high fluorescence of CDs and a model is established to investigate the mechanism of fluorescence. In addition, white light-emitting diodes (WLEDs) are fabricated by utilizing the prepared CDs and rare earth luminescent materials (SrSi2O2N2:Eu and Sr2Si5N8:Eu) as color conversion layers and UV-LED chips as the excitation light source. The WLEDs produce bright white light with attractive color rendering properties including a color rendering index of up to 95.1, a CIE coordinate of (0.33, 0.37), and a T c of 5447 K under a 100 mA driven current, indicating that the CDs are promising in the field of optoelectronic devices.
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The aim of the present study was to investigate the effect of HIF1α on Foxp3 expression in CD4(+) CD25(-) T lymphocytes. CD4(+) CD25(-) T lymphocytes were sorted from PBMC using a CD4(+) CD25(+) regulatory T cell isolation kit. Lentivirus containing lentiviral vector that overexpressed HIF1α (HIF-lenti) and those containing empty expression vector (control-lenti) were produced. Meanwhile, lentivirus that contained lentiviral vector that suppressed HIF1α expression (siHIF-lenti) and those containing control vector (sicontrol-lenti) were also generated. The sorted CD4(+) CD25(-) T lymphocytes were infected with HIF-lenti, control-lenti, siHIF-lenti, and sicontrol-lenti, respectively. Approximately 72 hr after transduction, real-time PCR and Western blot were carried out to analyze the RNA and protein expression level of HIF1α and Foxp3. CD4(+) CD25(-) T lymphocytes cultured under 21% O2 , 5% CO2 (normoxia) and 1% O2 , 5% CO2 (hypoxia) were used as control. Our results showed that overexpression of HIF1α increased both mRNA and protein expression of Foxp3 and, meanwhile, suppression of HIF1α expression by RNAi could reverse high Foxp3 expression in CD4(+) CD25(-) T lymphocytes caused by hypoxic culture. These results suggested that hypoxia could stimulate Foxp3 expression by increasing HIF1α expression in CD4(+) T lymphocytes which may promote CD4(+) T lymphocytes to convert to Treg.
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Linfócitos T CD4-Positivos/metabolismo , Fatores de Transcrição Forkhead/genética , Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subpopulações de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular , Fatores de Transcrição Forkhead/metabolismo , Humanos , Hipóxia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismoRESUMO
p-type ZnSe nanowires (NWs) with tunable electrical conductivity were fabricated on a large scale by evaporating a mixed powder composed of ZnSe and Sb in different ratios. According to the structural characterization, the Sb-doped ZnSe NWs are of single crystalline form and grow along the [001] direction. The presence of Sb in the ZnSe NWs was confirmed by XPS spectra. Electrical measurement of a single ZnSe:Sb NW based back-gate metal-oxide field-effect-transistor reveals that all the doped NWs exhibit typical p-type conduction characteristics, and the conductivity can be tuned over eight orders of magnitude, from 6.36 × 10(-7) S cm(-1) for the undoped sample to â¼37.33 S cm(-1) for the heavily doped sample. A crossed p-n nano-heterojunction photodetector made from the as-doped nanostructures displays pronounced rectification behavior, with a rectification ratio as high as 10(3) at ±5 V. Remarkably, it exhibits high sensitivity to ultraviolet light illumination with good reproducibility and quick photoresponse. Finally, the work mechanism of such a p-n junction based photodetector was elucidated. The generality of the above result suggests that the as-doped p-type ZnSe NWs will find wide application in future optoelectronics devices.
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The writing performance of the easy-cone magnetic tunnel junction (MTJ) and perpendicularly magnetized MTJ (pMTJ) under various temperatures was investigated based on the macrospin model. When the temperature is changed from 273 K to 373 K, the switching current density of the pMTJ changes by 56%, whereas this value is only 8% in the easy-cone MTJ. Similarly, the temperature-induced variation of the switching delay is more significant in the pMTJ. This indicates that the easy-cone MTJ has a more stable writing performance under temperature variations, resulting in a wider operating temperature range. In addition, these two types of MTJs exhibit opposite temperature dependence in the current overdrive and write error rate. In the easy cone MTJ, these two performance metrics will reduce as temperature is increased. The results shown in this work demonstrate that the easy-cone MTJ is more suitable to work at high temperatures compared with the pMTJ. Our work provides a guidance for the design of STT-MRAM that is required to operate at high temperatures.