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A new MnCuNiFeZn high entropy damping alloy was prepared. The microstructure, damping properties and phase transition characteristics of the alloy were studied by X-ray diffractometer, scanning electron microscopy, transmission electron microscopy, dynamic thermomechanical analyzer (DMA) and thermal dilatometer. The results show that the MnCuNiFeZn alloy is a single parent phase with uniform grain size and high fault density under solid solution and different aging processes. It is found that the magnetic transformation of the alloy occurs at room temperature with the extension of aging time, but the internal friction value at room temperature is very low. However, the internal friction value of MnCuNiFeZn alloy increases sharply in the high-temperature domain above 673 K due to the phase transformation.

Abstract Background and purpose Glucose-to-glycated hemoglobin ratio (GAR) is considered a more reliable marker of stress hyperglycemia by correcting for basal blood glucose levels. This study aimed to investigate the extent to which GAR is associated with 3 month and 1 year all-cause mortalities in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy (MT). Methods We retrospectively followed 553 AIS patients who underwent MT. The degree of stress hyperglycemia was quantified as the GAR, defined as fasting plasma glucose (mmol/L)/hemoglobin A1c (HbA1c) (%) on the second day after admission. According to the GAR quartiles, the patients were further categorized into four groups (group 1-group 4). We assessed the association between GAR and all-cause mortalities, clinical outcomes during hospitalization and function outcomes at 3 months. The associations between stress hyperglycemia and all-cause mortalities were analyzed using a Cox proportional-hazards model, while other outcomes were analyzed using multiple logistic regression analysis. Results The follow-up lasted a median of 18 months (range 0–66 months). The 3 month mortality rate was 9.58% (n = 53) and the 1 year mortality rate was 18.62% (n = 103). The Kaplan–Meier analysis revealed a significant inverse relationship between GAR and mortality (P

Objective: It solved the problem of low accuracy and large random error when cutting fresh corn, which is easy to damage the grain. Methods: A new process of sweet and waxy corn processing production line was designed, the production line used machine vision technology to judge the attitude of corn, completed the adjustment of corn attitude through reversing equipment, designed adaptive positioning structure to cut the head and tail of corn, and then carried out layer retention processing according to the difference characteristics of ear bract adhesion after cutting results, packed after camera quality screening, and used prototype to carry out processing tests. Results: The processing efficiency of the production line was up to 1 500 spikes/h, the pass rate of retention layer was 90.2%, and the grain breakage rate was 1.81%. Conclusion: The fresh corn processing production line realizes the automation of corn feeding, sorting, cutting, peeling and other processes, realizes the reasonable retention of bracts and leaves, and protects corn grains more than traditional equipment.

Interatomic potential is a key component of large-scale atomic simulation of materials. For scientific problems in complex environments such as high temperature，high pressure and irradiation，the interactions between atoms are often very complex. The empirical force field only considers two-body，three-body or four-body interactions between atoms. The physical assumption is simple，and it is often difficult to accurately describe the potential energy surface of complex environment. Machine learning force fields can obtain potential energy surfaces that are more accurate than empirical force fields. In this paper，a machine learning force field based on physical model is proposed for BaZrO3，the most common perovskite system，to describe the static properties，phase stability and mechanical properties of BaZrO3. The density functional theory database is used to train the machine learning force field based on physical model，and the static properties，phase stability and mechanical properties are calculated. For the static properties，the elastic constants C11，C12 and C44 were computed using both a pure machine-learning force field and a machine-learning force field based on a physical model，and the simulation results were much better than the empirical force field when compared to the DFT with errors of 0.34%，8.75% and 10.71% for the former，and 0.34%，2.5% and 7.14% for the latter. As for the phase stability，it is found that the machine learning force field based on physical model inherits the advantage of the empirical force field in maintaining the phase stability，which is better than the pure machine learning force field. For mechanical properties，Young's modulus of four different crystal directions of BaZrO3 are calculated. It was found that the errors between the calculated and experimental values for the machine learning force field and the machine learning force field based on the physical model were 9.22% and 1.6%，which were much lower than the results of the empirical force field. It can be seen that integrating physical models into the development of machine learning force field is an important way to improve the accuracy of atomic simulations.

The multi-axis manned centrifuge is an important device for training pilots' directional cognitive ability and overcoming illusions. Its intensity check is a necessary part of structural design. The traditional quasi-static static analysis method can only directly analyze the structural strength problem of no more than two-axis nested rotation, but the multi-axis manned centrifuge has three or more than three-axis nested rotation. The flexible multi-body dynamics method can be used to analyze and determine the strength of the multi-axis rotating structure of the motion path, but the calculation time is long and the resource consumption is large, so it is difficult to fully assess the intensity of the structure. In this paper, a multi-axis centrifuge intensity check method based on multi-body dynamics combined with random sampling and finite element calculation is proposed. The calculation results can be obtained in a relatively short period of time, it is highly efficient and feasible, which is conducive to improve the accuracy of structural intensity verification of multi-axis nested rotating equipment, and provides important support for its structural design.

Few studies have investigated the properties and protein composition of small extracellular vesicles (sEVs) derived from neurons under hypoxic conditions. Presently, the extent of the involvement of these plentiful sEVs in the onset and progression of ischemic stroke remains an unresolved question. Our study systematically identified the characteristics of sEVs derived from neurons under hypoxic conditions (HypEVs) by physical characterization, sEV absorption, proteomics and transcriptomics analysis. The effects of HypEVs on neurites, cell survival, and neuron structure were assessed in vitro and in vivo by neural complexity tests, magnetic resonance imaging (MRI), Golgi staining, and Western blotting of synaptic plasticity-related proteins and apoptotic proteins. Knockdown of Fused in Sarcoma (FUS) small interfering RNA (siRNA) was used to validate FUS-mediated HypEV neuroprotection and mitochondrial mRNA release. Hypoxia promoted the secretion of sEVs, and HypEVs were more easily taken up and utilized by recipient cells. The MRI results illustrated that the cerebral infarction volume was reduced by 45% with the application of HypEVs, in comparison to the non- HypEV treatment group. Mechanistically, the FUS protein is necessary for the uptake and neuroprotection of HypEVs against ischemic stroke as well as carrying a large amount of mitochondrial mRNA in HypEVs. However, FUS knockdown attenuated the neuroprotective rescue capabilities of HypEVs. Our comprehensive dataset clearly illustrates that FUS-mediated HypEVs deliver exceptional neuroprotective effects against ischemic stroke, primarily through the maintenance of neurite integrity and the reduction of mitochondria-associated apoptosis.

Byline: L. Li, L. Wang, G. Xu, F. Yang, Q. Gao, H. Niu, B. Shi, X. Jiang Background: Renal cancer is one of the common malignant tumors of the urinary [...]

Abstract Many orphan G protein-coupled receptors (GPCRs) remain understudied because their endogenous ligands are unknown. Here, we show that a group of class A/rhodopsin-like orphan GPCRs including GPR61, GPR161 and GPR174 increase the cAMP level similarly to fully activated D1 dopamine receptor (D1R). We report cryo-electron microscopy structures of the GPR61‒Gs, GPR161‒Gs and GPR174‒Gs complexes without any exogenous ligands. The GPR174 structure reveals that endogenous lysophosphatidylserine (lysoPS) is copurified. While GPR174 fails to respond to exogenous lysoPS, likely owing to its maximal activation by the endogenous ligand, GPR174 mutants with lower ligand binding affinities can be specifically activated by lysoPS but not other lipids, in a dose-dependent manner. Moreover, GPR174 adopts a non-canonical Gs coupling mode. The structures of GPR161 and GPR61 reveal that the second extracellular loop (ECL2) penetrates into the orthosteric pocket, possibly contributing to constitutive activity. Our work definitively confirms lysoPS as an endogenous GPR174 ligand and suggests that high constitutive activity of some orphan GPCRs could be accounted for by their having naturally abundant ligands.

ObjectiveTo understand the concentration of heavy metal cadmium and cadmium in portunus and mantis shrimp， and to timely identify food safety problems and potential hazards.MethodsPortunus and mantis shrimp samples from different provinces were collected and categorized based on different regions and locations， and some samples were made from tissue parts. Graphite furnace atomic absorption spectrometry was used to detect cadmium items， the cadmium exposure of portunus and mantis shrimp was evaluated simultaneouslyResultsThe detection rate of cadmium in 124 batches of portunus sold in Shanghai was 100% （124/124）， the detection rate of cadmium in 63 batches of mantis shrimp sold in the market was also 100% （63/63）. The cadmium content varied in different tissue parts， and the cadmium enrichment in hepatopancreas was the highest in the edible parts of portunus and mantis shrimp. The average detection value， 50th percentile value， 95th percentile value of cadmium in the hepatopancreas of portunus accounted for 52.64%， 49.28% and 98.65% of the PTMI， respectively. The average detection value， 50th percentile value and 95th percentile value of cadmium in the hepatopancreas of mantis shrimp accounted for 30.76%， 32.04% and 46.16% of the PTMI， respectively.ConclusionThe average residual levels of heavy metal cadmium in portunus and mantis shrimp are within the safe range.