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1.
Small ; : e2403310, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773872

RESUMEN

Understanding the structure-activity correlation is an important prerequisite for the rational design of high-efficiency electrocatalysts at the atomic level. However, the effect of coordination environment on electrocatalytic oxygen evolution reaction (OER) remains enigmatic. In this work, the regulation of proton transfer involved in water oxidation by coordination engineering based on Co3(PO4)2 and CoHPO4 is reported. The HPO4 2- anion has intermediate pKa value between Co(II)-H2O and Co(III)-H2O to be served as an appealing proton-coupled electron transfer (PCET) induction group. From theoretical calculations, the pH-dependent OER properties, deuterium kinetic isotope effects, operando electrochemical impedance spectroscopy (EIS) and Raman studies, the CoHPO4 catalyst beneficially reduces the energy barrier of proton hopping and modulates the formation energy of high-valent Co species, thereby enhancing OER activity. This work demonstrates a promising strategy that involves tuning the local coordination environment to optimize PCET steps and electrocatalytic activities for electrochemical applications. In addition, the designed system offers a motif to understand the structure-efficiency relationship from those amino-acid residue with proton buffer ability in natural photosynthesis.

2.
Exp Cell Res ; 432(2): 113764, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659467

RESUMEN

Pancreatic cancer (PC) cell immune escape is a crucial element in PC malignant development. Some previous studies have reported that LncRNA NNT-AS1 played a carcinogenic role in various tumors. However, the effect of lncRNA NNT-AS1 in PC cell immune escape remains unclear. To evaluate PC cell immune escape, PC cells were co-cultured with CD8+ T cells under a hypoxic condition. PC cell proliferation and migration were evaluated using the colony formation assay and transwell assay. CD8+ T cell proliferation and aoptosis were measured using the carboxy fluorescein diacetate succinimidyl ester (CFSE) assay and flow cytometry. The secretion of antitumor cytokines was assessed using enzyme-linked immunosorbent assay (ELISA). The molecular interactions were analyzed using chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP), or dual-luciferase reporter gene assays. A tumor xenograft model was established to evaluate the effects of lncRNA NNT-AS1 on PC in vivo. It was found that lncRNA NNT-AS1 was highly expressed in PC, and its silencing inhibited hypoxia-induced PC cell growth and immune escape in vivo and in vitro. Mechanically, HIF-1α transcriptionally activated NNT-AS1 expression and NNT-AS1 increased ITGB1 stability and expression in a METTL3-HuR dependent manner. ITGB1 overexpression reversed the inhibitory effects of NNT-AS1 knockdown on hypoxia-induced PC cell immune escape. In conclusion, Hypoxia promoted PC cell immune escape through lncRNA NNT-AS1/METTL3-HuR-mediated m6A modification to increase ITGB1 expression, which provided a theoretical foundation and a potential therapeutic target for PC.

3.
J Assist Reprod Genet ; 40(5): 1147-1161, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36930359

RESUMEN

PURPOSE: The objective of this study was to investigate the key glycolysis-related genes linked to immune cell infiltration in endometriosis and to develop a new endometriosis (EMS) predictive model. METHODS: A training set and a test set were created from the Gene Expression Omnibus (GEO) public database. We identified five glycolysis-related genes using least absolute shrinkage and selection operator (LASSO) regression and the random forest method. Then, we developed and tested a prediction model for EMS diagnosis. The CIBERSORT method was used to compare the infiltration of 22 different immune cells. We examined the relationship between key glycolysis-related genes and immune factors in the eutopic endometrium of women with endometriosis. In addition, Gene Ontology (GO)-based semantic similarity and logistic regression model analyses were used to investigate core genes. Reverse real-time quantitative PCR (RT-qPCR) of 5 target genes was analysed. RESULTS: The five glycolysis-related hub genes (CHPF, CITED2, GPC3, PDK3, ADH6) were used to establish a predictive model for EMS. In the training and test sets, the area under the curve (AUC) of the receiver operating characteristic curve (ROC) prediction model was 0.777, 0.824, and 0.774. Additionally, there was a remarkable difference in the immune environment between the EMS and control groups. Eventually, the five target genes were verified by RT-qPCR. CONCLUSION: The glycolysis-immune-based predictive model was established to forecast EMS patients' diagnosis, and a detailed comprehension of the interactions between endometriosis, glycolysis, and the immune system may be vital for the recognition of potential novel therapeutic approaches and targets for EMS patients.


Asunto(s)
Endometriosis , Humanos , Femenino , Endometriosis/diagnóstico , Endometriosis/genética , Aprendizaje Automático , Área Bajo la Curva , Grupos Control , Glucólisis/genética , Glipicanos , Proteínas Represoras , Transactivadores
4.
Mikrochim Acta ; 188(5): 156, 2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33825037

RESUMEN

A MnO2 nanosheet-assisted ratiometric fluorescence probe based on carbon quantum dots (CQDs) and o-phenylenediamine (OPD) has been developed for the detection of the anticancer drug 6-mercaptopurine (6-MP). CQDs with strong fluorescence are synthesized via the one-step hydrothermal method. MnO2 nanosheets as an oxidase-mimicking nanomaterial directly oxidize OPD into 2,3-diaminophenazine (DAP) which has a fluorescence emission at 570 nm, whereas the fluorescence of CQDs at 445 nm is then reduced by the DAP through the inner filter effect (IFE) under a single excitation wavelength (370 nm). After adding 6-MP, MnO2 nanosheets can be reduced to Mn2+ and lose their oxidase-like property, blocking the IFE with the fluorescence decrease of DAP and fluorescence increase of CQDs. The novel ratiometric fluorescence probe exhibits considerable sensitivity toward 6-MP and linear response is in the 0.46-100.0 µmol L-1 concentration range with the detection limit of 0.14 µmol L-1. Furthermore, the probe shows good selectivity when exposed to a series of interfering other organic and inorganic compounds, and biomolecules and can be applied to the detection for 6-MP in human serum samples and pharmaceutical tablets. Satisfactory recoveries of 6-MP in human serum samples are in the range 96.1-110.9% with the RSD of 1.4 to 3.2%. The amount of 6-MP is successfully estimated as 49.3 mg in pharmaceutical tablet with the RSD of about  2.2%.


Asunto(s)
Antineoplásicos/sangre , Colorantes Fluorescentes/química , Compuestos de Manganeso/química , Mercaptopurina/sangre , Óxidos/química , Fenilendiaminas/química , Puntos Cuánticos/química , Carbono/química , Humanos , Límite de Detección , Oxidación-Reducción , Espectrometría de Fluorescencia
5.
Nanotechnology ; 31(6): 065201, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31645022

RESUMEN

The artificial neural system has attracted tremendous attention in the field of artificial intelligence due to operate mode of parallel computation which is superior to traditional Von Neumann computers in processing complex sensory data and real-time situations with extremely low power dissipation. Remarkable progress has been made in the hardware-based electric-double-layer synaptic transistors as its modulation by ion movement is similar to biological synapse for the past few years. Unfortunately, long-term potentiation (LTP) timescale is still a big challenge in hardware-based electric-double-layer synaptic transistors which is essential to processing capacity and memory formation. Meanwhile, the effect of ion concentration on the synaptic plasticity has rarely been reported. Here, a solid state electrolyte-gated transistor using Ta2O5 as dielectric layer with unique ionic composition was demonstrated and the regulation of synaptic weight was realized by changing ion concentration. Both the potentiation and depression of synaptic weight such as excitatory post-synaptic current, inhibitory response (IPSC), paired pulse facilitation as well as LTP were successfully simulated. More importantly, oxygen vacancy content was tuned for the first time to modulate synaptic plasticity by varying film thickness and gas ratio, through which the intensity and duration of memory were enhanced with appropriate vacancy concentration. It indicated that appropriate vacancy concentration avoided the effects of internal electric field induced by ion excess, leading to a long-term memory. These results reveal a promising path to improve memory capacity of artificial synapse via ion modulation.


Asunto(s)
Plasticidad Neuronal , Óxidos/química , Tantalio/química , Compuestos de Estaño/química , Inteligencia Artificial , Redes Neurales de la Computación , Transistores Electrónicos
6.
BMC Genomics ; 19(1): 174, 2018 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-29499648

RESUMEN

BACKGROUND: Members of the MtN3/saliva/SWEET gene family are present in various organisms and are highly conserved. Their precise biochemical functions remain unclear, especially in Chinese cabbage. Based on the whole genome sequence, this study aims to identify the MtN3/saliva/SWEETs family members in Chinese cabbage and to analyze their classification, gene structure, chromosome distribution, phylogenetic relationship, expression pattern, and biological functions. RESULTS: We identified 34 SWEET genes in Chinese cabbage and analyzed their localization on chromosomes and transmembrane regions of their corresponding proteins. Analysis of a phylogenetic tree indicated that there were at least 17 supposed ancestor genes before the separation in Brassica rapa and Arabidopsis. The expression patterns of these genes in different tissues and flower developmental stages of Chinese cabbage showed that they are mainly involved in reproductive development. The Ka/Ks ratio between paralogous SWEET gene pairs of B. rapa were far less than 1. In our previous study, At2g39060 homologous gene Bra000116 (BraSWEET9, also named BcNS, Brassica Nectary and Stamen) played an important role during flower development in Chinese cabbage. Instantaneous expression experiments in onion epidermal cells showed that the gene encoding this protein is localized to the plasma membrane. A basal nectary split is the phenotype of transgenic plants transformed with the antisense expression vector. CONCLUSION: This study is the first to perform a sequence analysis, structures analysis, physiological and biochemical characteristics analysis of the MtN3/saliva/SWEETs gene in Chinese cabbage and to verify the function of BcNS. A total of 34 SWEET genes were identified and they are distributed among ten chromosomes and one scaffold. The Ka/Ks ratio implies that the duplication genes suffered strong purifying selection for retention. These genes were differentially expressed in different floral organs. The phenotypes of the transgenic plants indicated that BcNs participates in the development of the floral nectary. This study provides a basis for further functional analysis of the MtN3/saliva/SWEETs gene family.


Asunto(s)
Brassica rapa/metabolismo , Evolución Molecular , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Proteínas de Plantas/metabolismo , Brassica rapa/genética , Brassica rapa/crecimiento & desarrollo , Mapeo Cromosómico/métodos , Cromosomas de las Plantas , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Filogenia , Proteínas de Plantas/genética , Secuenciación Completa del Genoma/métodos
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 640-4, 2015 Mar.
Artículo en Zh | MEDLINE | ID: mdl-26117871

RESUMEN

Fluorescence interference is one of common interference factors during detection of Raman spectroscopy, while shifted-excitation Raman difference spectroscopy (SERDS) is an effective detection means to reject it. SERDS excites the test substance by two laser with different wavelengths, then difference the obtained Raman spectroscopies. SERDS can eliminate the fluorescence interference effectively, because the fluorescence backgrounds of the two spectroscopies are the same while the Raman peaks are translated. The key factor of SERDS is the stability of the two excitation light wavelengths, the instability of wavelength difference would seriously affect the characteristics of the Raman peak reproduction. In this paper, the Raman spectroscopy measurement system is presented, where dual wavelength laser module can stably produce two bunch of excitation light (respectively 784.7 and 785.8 nm), which satisfies the requirements of SERDS detection. The major factors influencing wavelength of the laser are laser power and temperature. The system monitors them in real time to guarantee the stability of exciting light's wavelength. The hardware framework of this measurement system is mainly composed of ARM, dual wavelength laser module as well as its driving circuit, temperature control circuit, a digital optical switch, a spectrometer; the software of this system can achieve the Raman spectrogram automatically and then carry on the subsequent processing. The stability tests of this system for drive current and laser temperature are done. The experimental results demonstrate that the range of current proves to be less than 0.01 mA, the range of temperature less than 0.004 degrees C. The system can guarantee the stability of excitation wavelength effectively. Finally, perform the Raman spectroscopy detection to sesame oil of some brand and get good results.

8.
Reprod Sci ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561472

RESUMEN

Endometriosis (EMT) -related infertility has been a challenge for clinical research. Many studies have confirmed that abnormal alterations in the immune microenvironment and glycolysis are instrumental in causing EMT-related infertility. Recently, our research team identified several key glycolysis-immune-related genes in the endometrial cells of EMT patients. This study aimed to further investigate the expression patterns of pyruvate dehydrogenase kinase 3 (PDK3), glypican-3 (GPC3), and alcohol dehydrogenase 6 (ADH6), which are related to glycolysis and immunity, in the follicular microenvironment of infertile patients with EMT using enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR) assays. According to the results, compared to the patients with tubal factor infertility, the concentrations of PDK3 and GPC3 were considerably increased in the follicular environment of EMT patients, while ADH6 expression was significantly reduced. The number of oocytes retrieved, the transferable embryo rate, and the cumulative clinical pregnancy rate of EMT patients were significantly reduced, and there was a correlation with the level of PDK3, GPC3, and ADH6 in Follicular Fluid (FF). The area under the receiver operating characteristic (ROC) curve for predicting clinical pregnancy in infertile patients with EMT for PDK3, GPC3, ADH6, and their combination was 0.732, 0.705, 0.855, and 0.879, respectively (P < 0.05). In conclusion, our research indicates that glycolysis-immune-related genes may contribute to infertility in EMT patients through immune infiltration, and disruption of mitochondrial and oocyte functions. The combined detection of PDK3, GPC3, and ADH6 in FF helps to predict clinical pregnancy outcomes in infertile patients with EMT.

9.
Nanomaterials (Basel) ; 14(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38668184

RESUMEN

It is usually difficult to realize high mobility together with a low threshold voltage and good stability for amorphous oxide thin-film transistors (TFTs). In addition, a low fabrication temperature is preferred in terms of enhancing compatibility with the back end of line of the device. In this study, α-IGZO TFTs were prepared by high-power impulse magnetron sputtering (HiPIMS) at room temperature. The channel was prepared under a two-step deposition pressure process to modulate its electrical properties. X-ray photoelectron spectra revealed that the front-channel has a lower Ga content and a higher oxygen vacancy concentration than the back-channel. This process has the advantage of balancing high mobility and a low threshold voltage of the TFT when compared with a conventional homogeneous channel. It also has a simpler fabrication process than that of a dual active layer comprising heterogeneous materials. The HiPIMS process has the advantage of being a low temperature process for oxide TFTs.

10.
Nat Commun ; 14(1): 1579, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36949063

RESUMEN

Limited by the inherent energy loss (Eloss) in carrier transport process, the device efficiency of organic solar cells shows inferior to traditional inorganic photovoltaic devices. Generally, molecular design, morphology optimization and interfacial engineering are usually required to alleviate Eloss. Here, vertical field-effect organic photovoltaic (VFEOPV) by integrating an bulk-heterojunction (BHJ) organic photovoltaic (OPV) with vertical field effect transistor (VFET) is invented, in which VFET generates a large, uneven, internal electric field, eliminating the requirement for driving force to dissociate excitons and prevents non-radiative recombination in OPV. In this way, the performance of solar cell can be well controlled by the gate voltage of VFET and the Eloss of VFEOPVs based on J71: ITIC system is dramatically reduced below 0.2 eV, significantly improving power conversion efficiency (PCE) from 10% to 18% under gate voltage of 0.9 V, which only causes negligible additional power consumption (~10-4mJ/cm2). Besides, the device also exhibits multi-functionality including transistor and phototransistors with excellent photodector performance. This work provides a new and general strategy to improve the OPV performance which is compatible with present optimization methods, and can be applied to improve PCE of other types of solar cells such as Perovskite and inorganic solar cells.

11.
Nat Commun ; 14(1): 2648, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37156788

RESUMEN

Realizing multi-modal information recognition tasks which can process external information efficiently and comprehensively is an urgent requirement in the field of artificial intelligence. However, it remains a challenge to achieve simple structure and high-performance multi-modal recognition demonstrations owing to the complex execution module and separation of memory processing based on the traditional complementary metal oxide semiconductor (CMOS) architecture. Here, we propose an efficient sensory memory processing system (SMPS), which can process sensory information and generate synapse-like and multi-wavelength light-emitting output, realizing diversified utilization of light in information processing and multi-modal information recognition. The SMPS exhibits strong robustness in information encoding/transmission and the capability of visible information display through the multi-level color responses, which can implement the multi-level pain warning process of organisms intuitively. Furthermore, different from the conventional multi-modal information processing system that requires independent and complex circuit modules, the proposed SMPS with unique optical multi-information parallel output can realize efficient multi-modal information recognition of dynamic step frequency and spatial positioning simultaneously with the accuracy of 99.5% and 98.2%, respectively. Therefore, the SMPS proposed in this work with simple component, flexible operation, strong robustness, and highly efficiency is promising for future sensory-neuromorphic photonic systems and interactive artificial intelligence.

12.
Reprod Sci ; 30(7): 2263-2274, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36690916

RESUMEN

The present study aimed to determine the clinical predictive significance of HIF-1α in follicular development and assisted reproductive technology (ART). We collected follicular fluid (FF) and granulosa cells (GCs) from PCOS (polycystic ovary syndrome) patients (experimental group) and other patients who were infertile due to tubal factors or male factors (control group) with IVF/ICSI-ET. The localization and expression of HIF-1α in GCs were determined by immunofluorescence staining. HIF-1α protein and mRNA expression were detected by enzyme-linked immunosorbent assay and quantitative real-time PCR, respectively. To clarify the regulation of HIF-1α by TGF-ß1, we added the HIF-1α-specific blocker YC-1 to GCs. The serum AMH, LH, LH/FSH, testosterone, BMI and the number of oocytes retrieved in the PCOS group were significantly higher, while the cleavage rate was significantly lower, than those in the control group. HIF-1α protein was expressed in the cytoplasm of GCs. The expression of HIF-1α protein in the FF of the PCOS group was significantly lower than that in the control group. However, the expression of HIF-1α protein in GCs between the two groups was not significantly different. HIF-1α protein was highly expressed in large FF (follicular diameter ≥ 14 mm). Compared with the control group, the expression of HIF-1α mRNA in GCs of the PCOS group was significantly lower. The results showed a significant positive correlation between HIF-1α and TGF-ß1 expression. We found that both HIF-1α and TGF-ß1 were involved in the development of PCOS follicular development. The mutual regulation of HIF-1α and TGF-ß1 may be one of the important mechanisms of the occurrence and development of PCOS.


Asunto(s)
Infertilidad , Síndrome del Ovario Poliquístico , Masculino , Femenino , Humanos , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Líquido Folicular/metabolismo , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Relevancia Clínica , Células de la Granulosa/metabolismo , Infertilidad/metabolismo , ARN Mensajero/metabolismo
13.
Front Plant Sci ; 13: 1064399, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36684756

RESUMEN

Visual Question Answering (VQA) about diseases is an essential feature of intelligent management in smart agriculture. Currently, research on fruit tree diseases using deep learning mainly uses single-source data information, such as visible images or spectral data, yielding classification and identification results that cannot be directly used in practical agricultural decision-making. In this study, a VQA model for fruit tree diseases based on multimodal feature fusion was designed. Fusing images and Q&A knowledge of disease management, the model obtains the decision-making answer by querying questions about fruit tree disease images to find relevant disease image regions. The main contributions of this study were as follows: (1) a multimodal bilinear factorized pooling model using Tucker decomposition was proposed to fuse the image features with question features: (2) a deep modular co-attention architecture was explored to simultaneously learn the image and question attention to obtain richer graphical features and interactivity. The experiments showed that the proposed unified model combining the bilinear model and co-attentive learning in a new network architecture obtained 86.36% accuracy in decision-making under the condition of limited data (8,450 images and 4,560k Q&A pairs of data), outperforming existing multimodal methods. The data augmentation is adopted on the training set to avoid overfitting. Ten runs of 10-fold cross-validation are used to report the unbiased performance. The proposed multimodal fusion model achieved friendly interaction and fine-grained identification and decision-making performance. Thus, the model can be widely deployed in intelligent agriculture.

14.
J Tissue Eng ; 13: 20417314221122123, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36093432

RESUMEN

To study the biological functions and applications of human amniotic epithelial cell-derived extracellular vesicles (hAEC-EVs), the cargos of hAEC-EVs were analyzed using miRNA sequencing and proteomics analysis. The hAECs and hAEC-EVs in this study had specific characteristics. Multi-omics analyses showed that extracellular matrix (ECM) reorganization, inhibition of excessive myofibroblasts, and promotion of target cell adhesion to the ECM were their primary functions. We evaluated the application of hAEC-EVs for corneal alkali burn healing in rabbits and elucidated the fundamental mechanisms. Slit-lamp images revealed that corneal alkali burns induced central epithelial loss, stromal haze, iris, and pupil obscurity in rabbits. Slit-lamp examination and histological findings indicated that hAEC-EVs facilitated re-epithelialization of the cornea after alkali burns, reduced scar formation and promoted the restoration of corneal tissue transparency. Significantly fewer α-SMA-positive myofibroblasts were observed in the hAEC-EV-treated group than the PBS group. HAEC-EVs effectively promoted the proliferation and migration of hCECs and hCSCs in vitro and activated the focal adhesion signaling pathway. We demonstrated that hAEC-EVs were excellent cell-free candidates for the treatment of ECM lesion-based diseases, including corneal alkali burns. HAEC-EVs promoted ECM reorganization and cell adhesion of target tissues or cells via orderly activation of the focal adhesion signaling pathway.

15.
ACS Appl Mater Interfaces ; 13(1): 1035-1042, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33378165

RESUMEN

Organic phototransistors with high sensitivity and responsivity to light irradiance have great potential applications in national defense, meteorology, industrial manufacturing, and medical security. However, undesired dark current and photoresponsivity limit their practical applications. Here, a novel vertical organic phototransistor combined with ferroelectric materials is developed. The device structure has nanometer channel length, which can effectively separate photogenerated carriers and reduce the probability of carrier recombination and defect scattering, thus improving the device performance of phototransistors. Moreover, by inserting the poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) ferroelectric layer, the Schottky barrier at the interface between the semiconductor and source can be adjusted by the polarization of the external electric field, which can effectively reduce the dark current of the phototransistor to further improve the device performance. Therefore, our phototransistors exhibit a high photoresponsivity of more than 5.7 × 105A/W, an outstanding detectivity of 1.15 × 1018 Jones, and an excellent photosensitivity of 5 × 107 under 760 nm light illumination, which are better than those of conventional lateral organic phototransistors. This work provides a new approach for the development of high-performance phototransistors, which opens a new pathway for organic phototransistors in practical application.

16.
ACS Appl Mater Interfaces ; 13(6): 7498-7509, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33533254

RESUMEN

Organic phototransistors (OPTs) have attracted enormous attention because of their promising applications in sensing, communication, and imaging. Currently, most OPTs reported utilize field-effect transistors (FETs) with relative long channel length which usually has undesired amplification because of their inherent low transconductance originated from their low channel capacitance, limiting the further improvement of performance. Herein, a vertical channel hybrid electrochemical phototransistor with a nanoscale channel and large transconductance (VECPT) is invented for the first time to achieve ultrahigh photoresponsivity along with a fast response speed. Benefiting from the nanoscale channel length and large transconductance, the photo-generated carriers in channel can be efficiently dissociated, transported, and amplified into the enlarged photocurrent output. Therefore, the devices deliver substantially improved optoelectronic performances with a photoresponsivity as high as ≈2.99 × 107 A/W, detectivity of ≈1.49 × 1013 Jones, and fast-speed response of ≈73 µs under a low voltage of 1 V, which are superior to those of the reported OPTs based on FETs. Moreover, the in situ Kelvin probe microscopy is performed to characterize the surface potential of device systems for better elucidating the photosensing mechanism. Furthermore, taking advantage of its excellent optoelectronic performance, an ultraviolet light monitoring system is constructed by integrating VECPT with a light-emitting diode, which also shows the real-time, high-sensitive, and controllable photoresponse threshold properties. All these results demonstrate the great potential of these electrochemical phototransistors and provide valuable insights into the design of the nanoscale channel length device system for high-performance photodetection.

17.
ACS Appl Mater Interfaces ; 13(7): 8672-8681, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33565852

RESUMEN

In recent years, much attention has been focused on two-dimensional (2D) material-based synaptic transistor devices because of their inherent advantages of low dimension, simultaneous read-write operation and high efficiency. However, process compatibility and repeatability of these materials are still a big challenge, as well as other issues such as complex transfer process and material selectivity. In this work, synaptic transistors with an ultrathin organic semiconductor layer (down to 7 nm) were obtained by the simple dip-coating process, which exhibited a high current switch ratio up to 106, well off state as low as nearly 10-12 A, and low operation voltage of -3 V. Moreover, various synaptic behaviors were successfully simulated including excitatory postsynaptic current, paired pulse facilitation, long-term potentiation, and long-term depression. More importantly, under ultrathin conditions, excellent memory preservation, and linearity of weight update were obtained because of the enhanced effect of defects and improved controllability of the gate voltage on the ultrathin active layer, which led to a pattern recognition rate up to 85%. This is the first work to demonstrate that the pattern recognition rate, a crucial parameter for neuromorphic computing can be significantly improved by reducing the thickness of the channel layer. Hence, these results not only reveal a simple and effective way to improve plasticity and memory retention of the artificial synapse via thickness modulation but also expand the material selection for the 2D artificial synaptic devices.

18.
ACS Appl Mater Interfaces ; 13(24): 28564-28573, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34100580

RESUMEN

Enormous synaptic devices are required to build a parallel, precise, and efficient neural computing system. To further improve the energy efficiency of neuromorphic computing, a single high-density synaptic (HDS) device with multiple nonvolatile synaptic states is suggested to reduce the number of synaptic devices in the neural network, although such a powerful synaptic device is rarely demonstrated. Here, a photoisomerism material, namely, diarylethene, whose energy level varies with the wavelength of illumination is first introduced to construct a powerful HDS device. The multiple synaptic states of the HDS device are intrinsically converted under UV-vis regulation and remain nonvolatile after the removal of illumination. More importantly, the conversion is reconfigurable and reversible under different light conditions, and the synaptic characteristics are comprehensively mimicked in each state. Finally, compared with a two-layer multilayer perceptron (MLP) architecture based on static synaptic devices, the HDS device-based architecture reduces the device number by 16 times to achieve a minimalist neural computing structure. The invention of the HDS device opens up a revolutionary paradigm for the establishment of a brain-like network.

19.
Analyst ; 135(5): 1124-30, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20419265

RESUMEN

A heated copper microdisk electrode (HCME) was fabricated and successfully applied to capillary electrophoresis (CE) and CE-Chip as an electrochemical detector (ECD) for the detection of three carbohydrates and shikimic acid (SA) in Illicium verum Hook F., respectively. The temperature of HCME was heated by twin-wire-wound coil with direct current to reduce the magnetic interference. Coupled with CE and CE-chip, this detector exhibits both extremely stable and sensitive performance at elevated temperature compared with that at room temperature. In successive detection of three carbohydrates and shikimic acid (SA), the HCME exhibits very stable response with RSD of ca. 2% with elevated temperature without renewing the electrode, while at room temperature, RSD of ca. 20% is obtained. This is very important in practical applications that tedious works, such as polishing and re-fixing the electrode at each detection, can be therefore avoided. In addition, the sensitivity is about 2-6 time increased, and the linear range is about an order wider at elevated temperature (ca. 60 degrees C) than that at room temperature (ca. 25 degrees C).

20.
Cancer Med ; 9(7): 2491-2499, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32023009

RESUMEN

Ovarian cancer (OVA) is a fatal and common malignancy in women worldwide. Circular RNAs (circRNAs) consist of a family of circular endogenous RNAs generated by selective splicing, and they are involved in many diseases. Previous studies reported that hsa_circ_0007874 is aberrantly expressed in cancer and functions in tumorigenesis. While the hsa_circ_0007874 role in OVA is unclear. Here, we detected the hsa_circ_0007874 expression in OVA cell lines using Rt-qPCR. Hsa_circ_0007874 subcellular localization was confirmed by fluorescence in situ hybridization. The relationship between hsa_circ_0007874, microRNAs (miRNAs), and relative protein levels was assessed using the luciferase reporter assays. Results verified that hsa_circ_0007874 is downregulated in OVA cell lines. hsa_circ_0007874 overexpression decreased the OVA cell migration and proliferation in vitro and in vivo. Bioinformatics and luciferase reporter assays confirmed that miR-760 and SOCS3 are the downstream targets of hsa_circ_0007874. Downregulation of SOCS3 or miR-760 overexpression restored the migration and proliferation ability of SKOV3 or A2780 cells overexpressing hsa_circ_0007874. Downregulation of SOCS3 restored the proliferation and migration in miR-760 knockdown SKOV3 and A2780 cells. In summary, the data suggest that hsa_circ_0007874 acts as a tumor suppressor by regulating the miR-760/SOCS3 axis, highlighting its potential as an effective therapeutic target for OVA.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Ováricas/patología , ARN Circular/genética , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Animales , Apoptosis , Biomarcadores de Tumor/genética , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
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