Oscillatory Neural Network-Based Ising Machine Using 2D Memristors.

Neural networks are increasingly used to solve optimization problems in various fields, including operations research, design automation, and gene sequencing. However, these networks face challenges due to the nondeterministic polynomial time (NP)-hard issue, which results in exponentially increasing computational complexity as the problem size grows. Conventional digital hardware struggles with the von Neumann bottleneck, the slowdown of Moore's law, and the complexity arising from heterogeneous system design. Two-dimensional (2D) memristors offer a potential solution to these hardware challenges, with their in-memory computing, decent scalability, and rich dynamic behaviors. In this study, we explore the use of nonvolatile 2D memristors to emulate synapses in a discrete-time Hopfield neural network, enabling the network to solve continuous optimization problems, like finding the minimum value of a quadratic polynomial, and tackle combinatorial optimization problems like Max-Cut. Additionally, we coupled volatile memristor-based oscillators with nonvolatile memristor synapses to create an oscillatory neural network-based Ising machine, a continuous-time analog dynamic system capable of solving combinatorial optimization problems including Max-Cut and map coloring through phase synchronization. Our findings demonstrate that 2D memristors have the potential to significantly enhance the efficiency, compactness, and homogeneity of integrated Ising machines, which is useful for future advances in neural networks for optimization problems.

Construction of covalent organic framework nanozymes with photo-enhanced hydrolase activities for colorimetric sensing of organophosphorus nerve agents.

Construction of covalent organic frameworks (COFs)-based nanozymes is of great importance for the extensive applications in catalysis and sensing fields. In this work, a two-dimensional COF (DAFB-DCTP COF) was fabricated via Knoevenagel condensation reaction. The integration of catalytically active sites of pyridine groups into the donor-acceptor (D-A) conjugated skeleton endows DAFB-DCTP COF with both hydrolytic and photosensitive properties. The DAFB-DCTP COF can be utilized as an artificial enzyme with selective and photo-enhanced catalytic efficiency, facilitating its application in photocatalytic degradation of hydrolase substrates (p-nitrophenyl acetate, pNPA) by nucleophilic reaction and further realizing colorimetric detection of the nanozyme inhibitor of organophosphorus nerve agent (diethyl cyanophosphonate, DCNP). The distinct color changes could be distinguished by naked eyes even at a low DCNP concentration, and the versatile smartphone analysis featured with reliability and simplicity. For the first time, the COFs' intrinsic hydrolase activity depending on their structural characteristics was investigated in synergy with the photosensitive performance originating from their photoelectric features. The present contribution provides a promising direction towards construction of colorimetric sensing platform based on the regulation of COFs' non-oxidoreductase activity under visible light irradiation.

Constructing van der Waals heterostructures by dry-transfer assembly for novel optoelectronic device.

Since the first successful exfoliation of graphene, the superior physical and chemical properties of two-dimensional (2D) materials, such as atomic thickness, strong in-plane bonding energy and weak inter-layer van der Waals (vdW) force have attracted wide attention. Meanwhile, there is a surge of interest in novel physics which is absent in bulk materials. Thus, vertical stacking of 2D materials could be critical to discover such physics and develop novel optoelectronic applications. Although vdW heterostructures have been grown by chemical vapor deposition, the available choices of materials for stacking is limited and the device yield is yet to be improved. Another approach to build vdW heterostructure relies on wet/dry transfer techniques like stacking Lego bricks. Although previous reviews have surveyed various wet transfer techniques, novel dry transfer techniques have been recently been demonstrated, featuring clean and sharp interfaces, which also gets rid of contamination, wrinkles, bubbles formed during wet transfer. This review summarizes the optimized dry transfer methods, which paves the way towards high-quality 2D material heterostructures with optimized interfaces. Such transfer techniques also lead to new physical phenomena while enable novel optoelectronic applications on artificial vdW heterostructures, which are discussed in the last part of this review.

Serum CXCL10/IP-10 may be a potential biomarker for severe Mycoplasma pneumoniae pneumonia in children.

BACKGROUND: How to early distinguish the severity of Mycoplasma pneumoniae pneumonia (MPP) is a worldwide concern in clinical practice. We therefore conducted this study to assess the relationship between levels of serum inflammatory chemokines and the severity of MPP. METHODS: In this prospective study, we enrolled 39 children with MPP, whose clinical information was collected, blood samples were assayed for cytokines and chemokines by ELISA. RESULTS: The levels of serum CXCL10 in children with severe MPP were significantly higher than those in children with mild MPP (2500.0 [1580.9-2500.0] vs. 675.7 [394.7-1134.9], P < 0.001). Measurement of CXCL10 levels in serum enabled the differentiation of children with severe MPP with an area under the curve (AUC) of 0.885 (95 % CI 0.779-0.991, P < 0.001), with a sensitivity of 81.0 % and a specificity of 83.3 %. CONCLUSIONS: Serum CXCL10 level may be a potential biomarker for severe MPP in children.

miR-374b-5p is increased in deep vein thrombosis and negatively targets IL-10.

BACKGROUND: Deep venous thrombosis (DVT) is one of the most common venous thromboembolic (VTE) disorders and the third leading cardiovascular complication. Accumulating evidence has shown that decreased interleukin-10 (IL-10) was involved in DVT. However, the underlying molecular mechanisms are still largely unknown. Here, we proposed that the epigenetic modification of IL-10 at the post-transcriptional level may be a crucial trigger for IL-10 down-regulation in DVT. METHODS: miRNA expression in DVT was profiled by miRNA microarray analysis. The upstream miRNA regulators of IL-10 were predicted by in silico target prediction tools. The expression of IL-10 mRNA and miR-374b-5p were examined by quantitative real-time PCR (qRT-PCR) and the protein expression of IL-10 was detected by enzyme-linked immunoassay. Dual luciferase reporter assay was used to identify the interaction between miR-374b-5p and IL10. A murine model of DVT was developed and the localization of miR-374b-5p was visualized in vitro by fluorescence in situ hybridization. The biological effects of miR-374b-5p on IL-10 was examined both in vitro and in vivo. RESULTS: Microarray and qRT-PCR results showed that the IL-10 expression was decreased while miR-374b-5p level was increased substantially in peripheral blood mononuclear cells of DVT patients, and there was significant negative correlation between miR-374b-5p and IL-10. Experiments in vitro showed that overexpressed miR-374b-5p reduced IL-10 expression, while miR-374b-5p knockdown increased IL-10 expression. Moreover, in vivo studies revealed that DVT mice with anti-IL-10 antibody or agomiR-374b-5p delivery resulted in decreased IL-10 expression and aggravated DVT formation, whereas antagomiR-374b-5p acted inversely. Dual luciferase reporter assay identified direct binding between miR-374b-5p and IL10. CONCLUSIONS: These findings suggest that increased miR-374b-5p promotes DVT formation by downregulating IL-10 expression. miR-374b-5p may be explored as a promising diagnostic marker and therapeutic target for DVT.

Lung resided monocytic myeloid-derived suppressor cells contribute to premetastatic niche formation by enhancing MMP-9 expression.

In cancer patients, the prevalence of myeloid-derived suppressor cells (MDSCs) is correlated with the degree of malignancy. In the present study, we investigated the role of circulating M-MDSCs in premetastatic niche formation using a mouse syngeneic tumor model and found that there was an increased frequency of M-MDSCs in the peripheral blood of tumor-bearing mice. M-MDSCs tracking and lung tissue histological analyses revealed that the malignant conditions promote the residence of circulating M-MDSCs and increased tumor cell arrest in the lungs. We further found that MMP-9 expression was increased in the circulating M-MDSCs and the administration of an MMP-9 inhibitor suppressed M-MDSCs transplantation-induced tumor cell arrest in the lung. Therefore, our findings suggest that the expansion of circulating M-MDSCs during tumor progression contributes to premetastatic niche formation by increasing MMP-9 expression.

Recruited monocytic myeloid-derived suppressor cells promote the arrest of tumor cells in the premetastatic niche through an IL-1ß-mediated increase in E-selectin expression.

The tumor premetastatic niche initiated by primary tumors is constructed by multiple molecular factors and cellular components and provides permissive condition that allows circulating tumor cells to successfully metastasize. Myeloid-derived suppressor cells (MDSCs), a population of immature cells in pathological conditions, play a critical role in the formation of the premetastatic niche. However, few researches are focused on the function of monocytic MDSCs (mo-MDSCs), a subtype of MDSCs, in the construction of the niche. Here, we show that the number of mo-MDSCs is significantly increased in the premetastatic lungs of tumor-bearing mice, thus promoting tumor cell arrest and metastasis. Before the arrival of tumor cells, the lung-recruited mo-MDSCs produced IL-1ß, thereby increasing E-selectin expression and promoting tumor cell arrest on endothelial cells. Depletion of mo-MDSCs in the premetastatic lungs decreased IL-1ß production, resulting in reduced E-selectin expression. In addition, compared with alveolar macrophages and interstitial macrophages, mo-MDSCs were the major source of IL-1ß expression in the premetastatic lungs. Cytokine array analyses and transwell experiments revealed that CCL12 recruits mo-MDSCs to premetastatic lungs. CCL12 knockdown in tumor-bearing mice significantly decreased mo-MDSC infiltration into the premetastatic lungs, leading to reduced E-selectin expression. Overall, the permissive conditions produced by the infiltrated mo-MDSCs correlated with increased tumor cell arrest and metastasis. These results reveal a novel role of mo-MDSCs in constructing the premetastatic niche. Thus, inhibition of mo-MDSCs infiltration may change the premetastatic niche to normal condition and attenuate tumor metastasis.