The objective of this study was to investigate the recovery ability of polymerized porcine hemoglobin (pPolyHb) in a rat model of acute anemia caused by normovolemic hemodilution (ANH). After the ANH procedure, rats were infused with either pPolyHb or red blood cells. The results showed pPolyHb could carry a sufficient amount of oxygen to the tissues to maintain normal aerobic metabolism and hemodynamic stability, without any significant toxic effects on renal and liver function according to pathological, and biochemical analysis. The data suggest pPolyHb may be a good candidate for the treatment of acute anemia in future clinical trials.
Abstract It is of great significance to reveal the detailed mechanism of neighboring effects between monomers, as they could not only affect the intermediate bonding but also change the reaction pathway. This paper describes the electronic effect between neighboring Zn/Co monomers effectively promoting CO 2 electroreduction to CO. Zn and Co atoms coordinated on N doped carbon (ZnCoNC) show a CO faradaic efficiency of 93.2 % at −0.5 V versus RHE during a 30‐hours test. Extended X‐ray absorption fine structure measurements (EXAFS) indicated no direct metal–metal bonding and X‐ray absorption near‐edge structure (XANES) showed the electronic effect between Zn/Co monomers. In situ attenuated total reflection‐infrared spectroscopy (ATR‐IR) and density functional theory (DFT) calculations further revealed that the electronic effect between Zn/Co enhanced the *COOH intermediate bonding on Zn sites and thus promoted CO production. This work could act as a promising way to reveal the mechanism of neighboring monomers and to influence catalysis.
Cisplatin (DDP) resistance is one of the main causes of treatment failure in patients with colon cancer (CC). Autophagy is a key mechanism of resistance to chemotherapy. Since autophagy‑related 7 (ATG7) has been reported to be involved in the regulation of autophagy and DDP resistance for lung and esophageal cancer, the present study aimed to explore the functions of microRNA (miR)‑4486 in the autophagy‑mediated DDP resistance of CC. The expression level of miR‑4486 in HCT116, DDP‑resistant HCT116 cells (HCT116/DDP), SW480 and DDP‑resistant SW480 cells (SW480/DDP) was quantified by reverse transcription‑quantitative PCR. Western blotting was utilized to analyze the expression of ATG7, autophagy‑related proteins Beclin 1 and LC3‑I/II, as well as apoptosis‑related proteins Bcl‑2, Bax and cleaved‑caspase 3 in HCT116/DDP and SW480/DDP cells. The half maximal inhibitory concentration of DDP on all cell lines and the cell viability of HCT116/DDP and SW480/DDP cells were measured using Cell Counting Kit 8 assay. Luciferase assay was used to examine the potential targets of miR‑4486 and ATG7. The effects of upregulating mimic miR‑4486 expression on the apoptosis and autophagy of HCT116/DDP and SW480/DDP cells were determined by flow cytometry and electron microscopy, respectively. It was found that miR‑4486 expression was significantly decreased in HCT116/DDP and SW480/DDP cells compared with that in HCT116 and SW480 cells. Overexpression of miR‑4486 could increase the sensitivity of HCT116/DDP and SW480/DDP cells to DDP by reducing cell viability, promoting apoptosis and inhibiting autophagy through downregulating Beclin 1 expression and the LC3‑II/LC3‑I ratio. Additionally, ATG7 was identified to be a target gene of miR‑4486, where ATG7 overexpression could partially reverse the effects of miR‑4486 on cell viability and apoptosis by promoting the formation of autophagosomes. In conclusion, the present results demonstrated that miR‑4486 could reverse DDP resistance in HCT116/DDP and SW480/DDP cells by targeting ATG7 to inhibit autophagy.
In response to the problem that the degradation state of rolling bearings is difficult to identify effectively, this paper proposes a degradation identification scheme of rolling bearing based on the combination of Variational Mode Decomposition (VMD) and Support Vector Machine (SVM). The method is composed of two steps: a) decompose the original data by VMD; b) use the decomposed data as input of SVM for training and testing for classification. By numerical experiments among combinations of different features, the best combination of features based on the data of University of Cincinnati is determined. The performance of the scheme is verified by comparison of numerical experiments with other models. The numerical experiments show that the proposed method can identify the degraded state of rolling bearings more accurately and facilitate advanced maintenance planning, which plays an important role in improving the overall reliability of mechanical equipment operation.
Abstract Cu‐based electrocatalysts facilitate CO 2 electrochemical reduction (CO 2 ER) to produce multi‐carbon products. However, the roles of Cu 0 and Cu + and the mechanistic understanding remain elusive. This paper describes the controllable construction of Cu 0 ‐Cu + sites derived from the well‐dispersed cupric oxide particles supported on copper phyllosilicate lamella to enhance CO 2 ER performance. 20 % Cu/CuSiO 3 shows the superior CO 2 ER performance with 51.8 % C 2 H 4 Faraday efficiency at −1.1 V vs reversible hydrogen electrode during the 6 hour test. In situ attenuated total reflection infrared spectra and density functional theory (DFT) calculations were employed to elucidate the reaction mechanism. The enhancement in CO 2 ER activity is mainly attributed to the synergism of Cu 0 ‐Cu + pairs: Cu 0 activates CO 2 and facilitates the following electron transfers; Cu + strengthens *CO adsorption to further boost C−C coupling. We provide a strategy to rationally design Cu‐based catalysts with viable valence states to boost CO 2 ER.
For the park (system of systems) consisting of a set of identical systems, the mission of each time unit is shared by all the survival systems which could be overexploited to achieve the global park objective. This overexploitation is stressful for each individual system and increases its respective degradation. This leads to increase the probability of failure of the system before the next planned maintenance. Otherwise, the system can be subject to operational constraints such as the reduction of exploitation because of an excessive degradation. Such constraint could affect the overall objective. We propose in this study to analyze the problem of the maintenance resource allocation on a park of n identical systems for ensuring a given production goal on a two successive maintenance period. Each system is degrading due to cumulative load and can be totally or partially renewed only during planned maintenance. We propose to construct a simulation-based model for the profit assessment of the whole park on a given time horizon for different maintenance allocation policies given the different assumptions described above.
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