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The detection of human body temperature is one of the important indicators to reflect the physical condition. In order to accurately judge the state of the human body, a high-performance temperature sensor with fast response, high sensitivity, and good linearity characteristics is urgently needed. In this paper, the positive temperature characteristics of graphene–polydimethylsiloxane (PDMS) composite with high sensitivity were studied. Besides, doping polyaniline (PANI) with special negative temperature characteristics as the temperature compensation of the composite finally creatively solved the problem of sensor nonlinearity from the material level. Thus, the PANI:graphene and PDMS hybrid temperature sensor with extraordinary linearity and high sensitivity is realized by establishing the space-gap model and mathematical theoretical analysis. The prepared sensor exhibits high sensitivity (1.60%/°C), linearity (R2= 0.99), accuracy (0.3 °C), and time response (0.7 s) in the temperature sensing range of 25–40 °C. Based on this, the fabricated temperature sensor can combine with the read-out circuit and filter circuit with a high-precision analog digital converter (ADC) to monitor real-time skin temperature, ambient temperature, and respiratory rate, et al. This high-performance temperature sensor reveals its great potential in electronic skin, disease diagnosis, medical monitoring, and other fields.

Objective: This study aimed to identify microRNAs (miRNAs) involved in the development of perioperative neurocognitive disorders (PND). Methods: Plasma exosomal miRNA expression was examined in patients before and after cardiopulmonary bypass (CPB) using microarray and qRT-PCR and these patients were diagnosed as PND later. Elderly rats were subjected to CPB, and the cognitive functions were examined. Bioinformatics analysis was conducted to predict the targets of miR-214-3p. Rats were administered rno-miR-214-3p agomir before or after CPB to investigate the role of miR-214-3p in PND development. Results: We identified 76 differentially expressed plasma exosomal miRNAs in PND patients after surgery (P<0.05, ∣log2FC∣>0.58), including the upregulated hsa-miR-214-3p (P=0.002399392). Prostaglandin-endoperoxide synthase 2 (PTGS2) was predicted as a miR-214-3p target. In rats, CPB reduced the platform crossing numbers and target quadrant stay time, accompanied with hippocampal neuronal necrosis. The rno-miR-214-3p level was significantly increased in plasma exosomes but decreased in rat hippocampus after surgery, exhibiting a negative correlation (P<0.001, r=−0.762). A negative correlation between miR-214-3p and PTGS2 protein expression was also observed in the hippocampus after surgery. Importantly, rno-miR-214-3p agomir treatment, before or after surgery, significantly increased the platform crossing numbers (P=0.035) and target quadrant stay time (P=0.029) compared with negative control. Hippocampal PTGS2 protein level was increased in the untreated surgery group and decreased in response to rno-miR-214-3p agomir treatment before or after surgery (both P<0.05 vs.negative control). Conclusion: These data suggest that miR-214-3p/PTGS2 signaling contributes to the development of PND, serving as a potential therapeutic target for PND.

With the aim of developing novel annulations via ketene intermediates, allenyl imide and alkynoates bearing good leaving groups are used for their function in a tandem conjugate addition–elimination reaction (SN2′ type) promoted by nucleophilic phosphine catalysts. By utilizing thioamides as 1S,3N-bis-nucleophiles, [3+3] and [3+2] annulations have been established to allow rapid access to 1,3-thiazin-4-ones and 5-alkenyl thiazolones in high yields, respectively. Furthermore, the possible reaction mechanisms are proposed on the basis of deuterium labeling experiments and density functional theory calculations.

One-pot sequential reactions of aryldiazonium salts with amidines followed by the treatment of I2/KI under basic conditions provide 2,5-disubstituted tetrazoles in moderate to excellent yields. This one-pot synthesis has several advantages such as mild reaction conditions, short reaction time, convenient workup, and high yields, making this methodology practical.

The trivalent phosphine-catalyzed [4+1] spiro-annulation reaction of allenyl imide and activated methylene cyclocompounds has been developed for the construction of various spiro-2-cyclopenten-1-ones. Oxindoles, 3-isochromanones, and 2-indanones are selected as 1C synthons to capture the in situ-generated bis-electrophilic α,β-unsaturated ketenyl phosphonium intermediate, affording the corresponding monospiro- and bispiro-cyclopentenones in good to excellent yields (≤91%) under mild conditions. The primary attempt at asymmetric catalysis using monophosphine (R)-SITCP provides promising enantioselectivity (45% ee). A plausible reaction mechanism is also proposed.

Friction stir processing (FSP) was used to modify the microstructure and improve the mechanical properties and corrosion resistance of an Mg–Al–Ca alloy. The results demonstrated that, after FSP, the grain size of the Mg–Al–Ca alloy was decreased from 13.3 to 6.7 μm. Meanwhile, the Al8Mn5phase was broken and dispersed, and its amount was increased. The yield strength and ultimate tensile strength of the Mg–Al–Ca alloy were increased by 17.0% and 10.1%, respectively, due to the combination of fine grain, second phase, and orientation strengthening, while the elongation was slightly decreased. The immersion and electrochemical corrosion rates in 3.5 wt% NaCl solution decreased by 18.4% and 37.5%, respectively, which contributed to grain refinement. However, the stress corrosion cracking (SCC) resistance of the modified Mg–Al–Ca alloy decreased significantly, which was mainly due to the filiform corrosion induced by the Al8Mn5phase. SCC was mainly controlled by anodic dissolution, while the cathodic hydrogen evolution accelerated the SCC process.

Objective: We aim to investigate the anticancer effects and mechanisms of icaritin against breast cancer. Materials and Methods: Both estrogen receptor (ER) positive breast cancer cells MCF- 7 and ER-negative MDA-MB-231 cells were employed. We examined the effects of icaritin on the proliferation and migration by wound healing assay and transwell assay. Cell apoptosis and cell cycle of MCF-7 and MDA-MB-231 cells were analyzed using Flow cytometry. Cell autophagy of MCF-7 and MDA-MB-231 cells was assessed by western blotting, acridine orange staining and confocal microscopy. We also detected the expression of apoptosis-related genes by western blotting. In addition, an autophagy inhibitor was used to investigate whether cytoprotective autophagy was induced. Meanwhile, an ER inhibitor was utilized to explore whether ER was involved in autophagy. Results: Icaritin inhibited the proliferation and migration, and induced cell cycle arrest of both MDA-MB-231 and MCF-7 cells. Icaritin significantly induced apoptosis of MDA-MB- 231 cells by activating caspase-3. And icaritin stimulated autophagy in MCF-7 cells, as evidenced by increased LC3II/LC3I, enhanced p62 degradation, the accumulation of endogenous LC3 puncta formation, and the increased autophagy flux. Icaritin induced autophagy through upregulating the phosphorylation of AMPK and ULK1. Chloroquine, an autophagy inhibitor, increased icaritin-induced apoptosis and proliferation inhibition of MCF-7 cells. Meanwhile, tamoxifen, an ER inhibitor, reversed icaritin-induced autophagy and proliferation inhibition of MCF-7 cells. Conclusion: Our study demonstrated that the antitumor effects of icaritin against breast cancer are related to ER, which suggested that the status of ER should be considered in the clinical application of icaritin.

Exploring the state-of-the-art heterogeneous catalysts has been a general concern for sustainable and clean energy. Here, Pt-embedded CuOx–CeO2multicore–shell (Pt/CuOx–CeO2MS) composites are fabricated at room temperature via a one-pot and template-free procedure for catalyzing CO oxidation, a classical probe reaction, showing a volcano-shaped relationship between the composition and catalytic activity. We experimentally unravel that the Pt/CuOx–CeO2MS composites are derived from an interfacial autoredox process, where Pt nanoparticles (NPs) are in situ encapsulated by self-assembled ceria nanospheres with CuOxclusters adhered through deposition/precipitation–calcination process. Only Cu–O and Pt–Pt coordination structures are determined for CuOxclusters and Pt NPs in Pt/CuOx–CeO2MS, respectively. Importantly, the close vicinity between Pt and CeO2benefits to more oxygen vacancies in CeO2counterparts and results in thin oxide layers on Pt NPs. Meanwhile, the introduction of CuOxclusters is crucial for triggering synergistic catalysis, which leads to high resistance to aggregation of Pt NPs and improvement of catalytic performance. In CO oxidation reaction, both Ptδ+–CO and Cu+–CO can act as active sites during CO adsorption and activation. Nonetheless, redundant content of Pt or Cu will induce a strongly bound Pt–O–Ce or Cu–[Ox]–Ce structures in air-calcinated Pt/CuOx–CeO2MS composites, respectively, which are both deleterious to catalytic reactivity. As a result, the composition-dependent catalytic activity and superior durability of Pt/CuOx–CeO2MS composites toward CO oxidation reaction are achieved. This work should be instructive for fabricating desirable multicomponent catalysts composed of noble metal and bimetallic oxide composites for diverse heterogeneous catalysis.

Cardiovascular complications represent a leading cause of mortality in patients with type 2 diabetes mellitus (T2DM). During such complicated progression, subtle variations in the cardiovascular risk (CVR)-related biomarkers have been used to identify cardiovascular disease at the incipient stage. In this study we attempt to integrally characterize the progression of cardiovascular complications and to assess the beneficial effects of metformin combined with salvianolic acid A (Sal A), in Goto-Kakizaki (GK) rats with spontaneous T2DM. The rats were treated with metformin (200 mg·kg−1·d−1, ig) alone or in combination with Sal A (1 mg·kg−1·d−1, ip) at ages from 8 to 22 weeks. During the treatment, the levels of asymmetric dimethylarginine, L-arginine, superoxide dismutase, malondialdehyde, glucose, high density lipoprotein and low density lipoprotein were assessed. Based on alterations in these biomarkers, a mini-network balance model was established using matrixes and vectors. Radar charts were created to visually depict the disruption of CVR-related modules (endothelial function, oxidative stress, glycation and lipid profiles). The description for the progression of cardiovascular disorder was quantitatively represented by u, the dynamic parameter of the model. The modeling results suggested that untreated GK rats tended to have more severe cardiovascular complications than the treatment groups. Metformin monotherapy retarded disease deterioration, whereas the combination treatment ameliorated the disease progression via restoring the balance. The current study, which focused on the balance of the mini-network and interactions among CVR-related modules, proposes a novel method for evaluating the progression of cardiovascular complications in T2DM as well as a more beneficial intervention strategy.

The spiking neural network (SNN), closely inspired by the human brain, is one of the most powerful platforms to enable highly efficient, low cost, and robust neuromorphic computations in hardware using traditional or emerging electron devices within an integrated system. In the hardware implementation, the building of artificial spiking neurons is fundamental for constructing the whole system. However, with the slowing down of Moore's Law, the traditional complementary metal-oxide-semiconductor (CMOS) technology is gradually fading and is unable to meet the growing needs of neuromorphic computing. Besides, the existing artificial neuron circuits are complex owing to the limited bio-plausibility of CMOS devices. Memristors with volatile threshold switching (TS) behaviors and rich dynamics are promising candidates to emulate the biological spiking neurons beyond the CMOS technology and build high-efficient neuromorphic systems. Herein, the state-of-the-art about the fundamental knowledge of SNNs is reviewed. Moreover, we review the implementation of TS memristor-based neurons, and their systems, and point out the challenges that should be further considered from devices to circuits in the system demonstrations. We hope that this review could provide clues and be helpful for the future development of neuromorphic computing with memristors.

Various CuO-ZnO-ZrO2(CZZ) catalysts for methanol synthesis from CO2 hydrogenation were prepared by co-precipitation method. Small amount of silica was incorporated into CZZ catalyst to produce these modified ternary CZZ catalysts. The effects of silica on physicochemical and catalytic properties were studied by TG-DTG,XRD,BET,N2O chemisorption,H2-TPR,NH3-TPD and CO2-TPD techniques. The results show that the properties of catalysts were strongly influenced by the content of SiO2 used as promoter. The catalytic performance for methanol synthesis from CO2 hydrogenation was evaluated. The test results show that the CZZ catalyst modified with 4 wt.% SiO2 exhibits an optimum catalytic activity. The silica improves the dispersion of CuO and its modified CZZ catalysts exhibits higher specific surface area, which were confirmed to be responsible for excellent performance of the catalysts for methanol synthesis from CO2 hydrogenation.