Abstract
Recently, three-terminal synaptic devices have attracted considerable attention owing to their nondestructive weight-update behavior, which is attributed to the completely separated ...terminals for reading and writing. However, the structural limitations of these devices, such as a low array density and complex line design, are predicted to result in low processing speeds and high energy consumption of the entire system. Here, we propose a vertical three-terminal synapse featuring a remote weight update via ion gel, which is also extendable to a crossbar array structure. This synaptic device exhibits excellent synaptic characteristics, which are achieved via precise control of ion penetration onto the vertical channel through the weight-control terminal. Especially, the applicability of the developed vertical organic synapse array to neuromorphic computing is demonstrated using a simple crossbar synapse array. The proposed synaptic device technology is expected to be an important steppingstone to the development of high-performance and high-density neural networks.
This book addresses the difficulties of the optimization of complex systems. It does this via simulation models or other computation-intensive models involving possible stochastic effects and ...discrete choices.
Hepatocellular carcinoma (HCC) is the most common primary liver cancer worldwide and no pharmacological treatment is available that can achieve complete remission of HCC. Phospholysine ...phosphohistidine inorganic pyrophosphate phosphatase (LHPP) is a recently identified HCC tumor suppressor gene which plays an important role in the development of HCC and its inactivation and reactivation has been shown to result in respectively HCC tumorigenesis and suppression. Small activating RNAs (saRNAs) have been used to achieve targeted activation of therapeutic genes for the restoration of their encoded protein through the RNAa mechanism. Here we designed and validated saRNAs that could activate LHPP expression at both the mRNA and protein levels in HCC cells. Activation of LHPP by its saRNAs led to the suppression of HCC proliferation, migration and the inhibition of Akt phosphorylation. When combined with targeted anticancer drugs (e.g., regorafenib), LHPP saRNA exhibited synergistic effect in inhibiting in vitro HCC proliferation and in vivo antitumor growth in a xenograft HCC model. Findings from this study provides further evidence for a tumor suppressor role of LHPP and potential therapeutic value of restoring the expression of LHPP by saRNA for the treatment of HCC.
The accurate prediction of soybean yield is of great significance for agricultural production, monitoring and early warning. Although previous studies have used machine learning algorithms to predict ...soybean yield based on meteorological data, it is not clear how different models can be used to effectively separate soybean meteorological yield from soybean yield in various regions. In addition, comprehensively integrating the advantages of various machine learning algorithms to improve the prediction accuracy through ensemble learning algorithms has not been studied in depth. This study used and analyzed various daily meteorological data and soybean yield data from 173 county-level administrative regions and meteorological stations in two principal soybean planting areas in China (Northeast China and the Huang–Huai region), covering 34 years. Three effective machine learning algorithms (K-nearest neighbor, random forest, and support vector regression) were adopted as the base-models to establish a high-precision and highly-reliable soybean meteorological yield prediction model based on the stacking ensemble learning framework. The model’s generalizability was further improved through 5-fold cross-validation, and the model was optimized by principal component analysis and hyperparametric optimization. The accuracy of the model was evaluated by using the five-year sliding prediction and four regression indicators of the 173 counties, which showed that the stacking model has higher accuracy and stronger robustness. The 5-year sliding estimations of soybean yield based on the stacking model in 173 counties showed that the prediction effect can reflect the spatiotemporal distribution of soybean yield in detail, and the mean absolute percentage error (MAPE) was less than 5%. The stacking prediction model of soybean meteorological yield provides a new approach for accurately predicting soybean yield.
Brain‑derived neurotrophic factor (BDNF) is known as one of the members of the neurotropin family. BDNF‑induced activation of its receptor tyrosine kinase B (TrkB) is associated with anoikis ...tolerance, tumor progression and poor prognosis in many types of malignancy. However, to the best of our knowledge, there are no reports describing the contribution of the BDNF/TrkB axis to cervical cancer. BDNF and TrKB expression in cervical cancer (CC) tissues and adjacent normal tissues from 87 patients were analyzed by immunohistochemistry, western blot analysis and quantitative PCR assays and the results showed that they were significantly higher in cancer tissues than that in normal adjacent tissues, respectively. Higher expression rates of BDNF and TrKB were observed in stage IIB or higher and BDNF expression was positively associated with lymph node metastasis. Notably, a high expression of TrKB may be contributed to poor survival time, which confirmed by Kaplan‑Meier analysis. Compared to the corresponding CC cell lines, HeLa, SiHa, CASKI, C4‑1 and C‑33a, BDNF and TrKB expression was enhanced in anoikis‑like apoptotic tolerance (AAT), a cell model established from cervical cancer cell lines. AAT cells showed a higher proliferation activity compared with CC cell lines, which was confirmed by a shorter G0/G1 phase, elevated cyclin A, cyclin D1 and c‑myc, decreased caspase‑3 and Bax, and increased Bcl‑2. By contrast, the knockdown of TrKB expression reversed these changes in AAT cells, induced G0/G1 arrest and suppressed proliferation activity. The results of the present study show that PI3K/Akt signaling is involved in the BDNF/TrKB‑induced proliferation of AAT cells in cervical cancer. These findings indicate that BDNF/TrKB pathway is a potential target for the treatment of cervical cancer.
Realization of biological synapses using electronic devices is regarded as the basic building blocks for neuromorphic engineering and artificial neural network. With the advantages of ...biocompatibility, low cost, flexibility, and compatible with printing and roll-to-roll processes, the artificial synapse based on organic transistor is of great interest. In this paper, the artificial synapse simulation by ion-gel gated organic field-effect transistors (FETs) with poly(3-hexylthiophene) (P3HT) active channel is demonstrated. Key features of the synaptic behaviors, such as paired-pulse facilitation (PPF), short-term plasticity (STP), self-tuning, the spike logic operation, spatiotemporal dentritic integration, and modulation are successfully mimicked. Furthermore, the interface doping processes of electrolyte ions between the active P3HT layer and ion gels is comprehensively studied for confirming the operating processes underlying the conductivity and excitatory postsynaptic current (EPSC) variations in the organic synaptic devices. This study represents an important step toward building future artificial neuromorphic systems with newly emerged ion gel gated organic synaptic devices.
To investigate the safety, local ablation efficacy, analgesic effects, and factors influencing the survival of patients with advanced pancreatic cancer treated with high-intensity focused ultrasound ...(HIFU).
Patients with advanced pancreatic cancer who underwent HIFU for the first time at the Suining Central Hospital between January 2018 and September 2022 were enrolled. The efficacy of tumor ablation was assessed using enhanced computed tomography (CT) and magnetic resonance imaging (MRI), pain relief was assessed using the visual analog scale (VAS), and complications and survival rates were investigated. The Kaplan-Meier method and a Cox regression model were used to analyze the independent risk factors that may have affected prognosis.
Intraoperative ultrasonography showed varying degrees of grayscale changes in all cases. One month after surgery, enhanced computed tomography or magnetic resonance imaging examinations showed complete or partial responses in 85.22% of the patients. Pain relief was achieved in 98.21% of the patients. No postoperative complications of SIR-C grade or higher were observed. The overall median survival time (MST) was 12.1 months. Cox multifactorial analysis showed that the main factors affecting overall survival (OS) were clinical stage, preoperative liver function, and combination chemotherapy.
HIFU is safe and effective for pancreatic cancer treatment, and has the potential to become an important supplement for the treatment of advanced pancreatic cancer. This approach needs to be further verified by multi-center and large-sample studies.
Owing to their potential advantages such as low-temperature processing, low-cost fabrication, large-area production, and mechanical flexibility, organic electrochemical transistors (OECTs) have ...gained considerable attention for bioelectronics. In this paper, we report on the fabrication of organic poly(3-hexylthiophene) (P3HT) synaptic transistors gated by the ionic liquid/poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TrFE) hybrid electrolyte. Because the formation of electric-double-layers (EDLs) can provide strong capacitive coupling within the boundary layer of hybrid electrolyte/P3HT channel interface, these organic devices exhibit low operating voltage and large hysteresis windows. The most important is that the bio-neural functions at synaptic domain including excitatory post-synaptic current (EPSC) and long-term synaptic plasticity were demonstrated. Under high gate presynaptic spike (|Vpre| = 2.0 V), an obvious non-volatile EPSC behaviors are observed, which are mainly due to an irreversible electrochemical doping effect. The hybrid electrolyte gated organic synaptic transistors provide a potential candidate for building neuromorphic systems.
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•Organic P3HT synaptic transistors gated by the ionic liquid/P(VDF-TrFE) hybrid electrolyte were demonstrated.•Excitatory post-synaptic current (EPSC) and long-term synaptic plasticity were simulated.•An obvious non-volatile EPSC behavior is observed, which are mainly due to an irreversible electrochemical doping effect.
High‐performance organic heterojunction phototransistors are fabricated using highly ordered copper phthalocyanine (CuPc) and para‐sexiphenyl (p‐6P) thin films. The p‐6P thin film plays an important ...role on the performance of CuPc/p‐6P heterojunction phototransistors. It acts as a molecular template layer to induce the growth of highly ordered CuPc thin film, which dramatically improves the charge transport and decreases the grain boundaries. On the other hand, the p‐6P thin film can form an effective heterojunction with CuPc thin film, which is greatly helpful to enhance the light absorption and photogenerated carriers. Under 365 nm ultraviolet light irradiation, the ratio of photocurrent and dark current and photoresponsivity of CuPc/p‐6P heterojunction phototransistors reaches to about 2.2 × 104 and 4.3 × 102 A W−1, respectively, which are much larger than that of CuPc phototransistors of about 2.7 × 102 and 7.3 A W−1, respectively. A detailed study carried out with current sensing atomic force microscopy proves that the photocurrent is predominately produced inside the highly ordered CuPc/p‐6P heterojunction grains, while the photocurrent produced at the boundaries between grains can be neglected. The research provides a good method for fabricating high‐performance organic phototransistors using a combination of molecular template growth and organic heterojunction.
High‐performance organic heterojunction phototransistors are fabricated using highly ordered copper phthalocyanine (CuPc) and para‐sexiphenyl (p‐6P) thin films. The ratio of photocurrent and dark current and photoresponsivity reach to about 2.2 × 104 and 4.3 × 102 A W−1, respectively. A detailed study is carried out with current sensing atomic force microscopy.
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