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This article investigates the sliding wear behavior of ZTA (zirconia toughened alumina) particle (ZTAp)- and NbC (niobium carbide) particle (NbCp)-reinforced Fe60 matrix composites (ZTAp–NbCp/Fe60). ZTAp–NbCp/Fe60 was produced through vacuum sintering and tested on an M-2000 wear-testing machine. As revealed by the results, the wear loss increased with the increase in rotation speed and load. Abrasive wear occurred in the mild wear region; adhesive wear and serious abrasive occurred in the moderate wear region; and fatigue wear and ZTAp broken occurred in the severe wear region. According to the aforementioned conclusions, a more clean and intuitive wear mechanism diagram was established. In the process of wear, ZTAp was well combined with the matrix, and there was no crack at the interface. Meanwhile, in the wear process, ZTAp could block furrow, weaken the wear of the micro-convex ring, and improve the sliding wear performance of the composite material.

The interaction between cerebellum and cerebrum participates widely in function from motor processing to high‐level cognitive and affective processing. Because of the motor symptom, idiopathic generalized epilepsy (IGE) patients with generalized tonic–clonic seizure have been recognized to associate with motor abnormalities, but the functional interaction in the cerebello–cerebral circuit is still poorly understood. Resting‐state functional magnetic resonance imaging data were collected for 101 IGE patients and 106 healthy controls. The voxel‐based functional connectivity (FC) between cerebral cortex and the cerebellum was contacted. The functional gradient and independent components analysis were applied to evaluate cerebello–cerebral functional integration on the voxel‐based FC. Cerebellar motor components were further linked to cerebellar gradient. Results revealed cerebellar motor functional modules were closely related to cerebral motor components. The altered mapping of cerebral motor components to cerebellum was observed in motor module in patients with IGE. In addition, patients also showed compression in cerebello–cerebral functional gradient between motor and cognition modules. Interestingly, the contribution of the motor components to the gradient was unbalanced between bilateral primary sensorimotor components in patients: the increase was observed in cerebellar cognitive module for the dominant hemisphere primary sensorimotor, but the decrease was found in the cerebellar cognitive module for the nondominant hemisphere primary sensorimotor. The present findings suggest that the cerebral primary motor system affects the hierarchical architecture of cerebellum, and substantially contributes to the functional integration evidence to understand the motor functional abnormality in IGE patients. [ABSTRACT FROM AUTHOR]

The new era puts forward higher requirements on the quality of hospital management personnel, so it is significant to improve their health management research capabilities and encourage them to solve practical difficulties through scientific research as well as make innovations to their management thinking. In this article, a questionnaire survey of 100 hospital management personnel was carried out in a tertiary hospital in Guangzhou, China, to identify their health management research capabilities and learning needs for related knowledge. The results showed that most of the interviewees were young and middle-aged women with relatively high academic qualifications, mainly in medical and management majors. Their scientific research knowledge base and learning needs are on the average, and their scientific research method foundation is relatively ideal. There are significant differences in scientific research knowledge base, scientific research training needs, and scientific research methods among those with different ages and educational levels (p

High mobility spin-polarized two-dimensional electron gas (2DEG) is crucially important for spintronic applications. Here, we report our investigations on the 2DEG fabricated by spin coating a LaAlO3 layer on a (001) SrTiO3 substrate with a La2/3Sr1/3MnO3 buffer layer. When the buffer layer is below 3 uc, the 2DGE is highly mobile. Corresponding to the layer thicknesses of 0, 1, and 2 uc, the Hall mobilities are ∼24 000 cm2/V s, ∼28 000 cm2/V s, and ∼59 600 cm2/V s at 2 K. In contrast, the 2DEG with a buffer layer of 3 uc shows a relatively low mobility (∼3000 cm2/V s). However, an anomalous Hall effect was observed in this 2DEG below 20 K, indicating a long range ferromagnetic order. This work demonstrates the great potential of the chemical method in gaining high quality spin-polarized 2DEGs at the LaAlO3/SrTiO3 interface. [ABSTRACT FROM AUTHOR]

We investigated the anisotropic magnetoresistance (AMR) effects for La0.67(Ca1-xSrx)0.33MnO3 films epitaxially grown on (001) oriented SrTiO3 substrates. The increase of Sr doping gives rise to the enhancement of the metal-insulator transition temperature, but suppresses the AMR amplitude. The dependence of AMR on the magnetic field orientation for the Sr doping samples shows the coexistence of two-fold and four-fold symmetries, which is changed with varying the temperature. Moreover, the sign of AMR is changed from negative to positive with increasing the temperature. The abnormal AMR behaviors can be understood by different s-d scattering occurring at different temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Cellular therapies have revolutionized the treatment of hematological malignancies since their conception and rapid development. Chimeric antigen receptor (CAR)-T cell therapy is the most widely applied cellular therapy. Since the Food and Drug Administration approved two CD19-CAR-T products for clinical treatment of relapsed/refractory acute lymphoblastic leukemia and diffuse large B cell lymphoma in 2017, five more CAR-T cell products were subsequently approved for treating multiple myeloma or B cell malignancies. Moreover, clinical trials of CAR-T cell therapy for treating other hematological malignancies are ongoing. Both China and the United States have contributed significantly to the development of clinical trials. However, CAR-T cell therapy has many limitations such as a high relapse rate, adverse side effects, and restricted availability. Various methods are being implemented in clinical trials to address these issues, some of which have demonstrated promising breakthroughs. This review summarizes developments in CAR-T cell trials and advances in CAR-T cell therapy., (Copyright © 2023 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.)

BACKGROUND Different responses to identical trauma may be related to the genetic background of individuals, but the molecular mechanism is unclear. In this study we investigated the heterogeneity of trauma in mice and the potential biological explanations for the differences. MATERIAL AND METHODS Compared with other organs, the pathological response of the lung after injury is the earliest and most serious. We used C57BL/6 and BALB/C mice to explore the genetic background of different responses to trauma in the lung. We measured mortality rate, pulmonary microvascular permeability, and Cxcl15 gene expression in BALB/C and C57BL/6 mice before and after blast-wave injury. Microvascular permeability was measured using a fluorescent tracer, and Cxcl15 gene expression level and expression distribution were measured using fluorogenic probe quantitative polymerase chain reaction and northern blot. RESULTS C57BL/6 mice showed lower mortality rates and pulmonary microvascular permeability than BALB/C mice after blast-wave injury; there was no significant difference in the permeability before blast-wave injury. The Cxcl15 gene was expressed specifically in the lung tissue of mice. The level of Cxcl15 expression in BALB/C mice was higher than in C57BL/6 mice before and after injury, and the variation trend of Cxcl15 expression level after injury was significantly different between BALB/C and C57BL/6 mice. CONCLUSIONS Our results indicated that BALB/C and C57BL/6 mice had significant heterogeneity in posttraumatic response in terms of mortality and degree of lung damage. The differences in genetic factors such as Cxcl15 may have played a role in this heterogeneity.

Objective: To make a histological evaluation of poly (dextrogyr-levogyr)lactide acid-triiodothyronine (PDLLA-T3) in sciatic nerve defect of rat., Methods: Ninety SD rats were evenly divided into 3 groups (autograft group A, PDLLA-T3 group B and PDLLA group C). Group D was control group. The left sciatic nerves were cut off by operation and 1 cm-nerve-defect was set up. The specimens were collected 2 weeks, 1 month and 2 months after the operation respectively, simultaneously the right sciatic nerves were collected as normal control group D. HE staining, electron microscope, S-100 immunohistochemistry, and Bielschowsky staining were done in all the specimens, the quantity and quality of the regenerated nerves were observed, and all the results were processed by image analyzer., Results: Two weeks after the operation,histological observation indicated that the materials in groups B and C were not completely degraded. Transmission electron microscopic observation showed that the myelin sheath was not thick and it was about 0.5 microm in thickness. There was no significant difference among the 3 groups. One month after the operation, histological observation indicated that in group A the regenerated nerves passed through the scaffold and in the new nerves there were regenerated blood vessels. The materials in groups B and C were not completely degraded. S-100 immunohistochemical observation and Bielschowsky staining showed that in group B PDLLA-T3 repaired the defect successfully and the regenerated nerve myelin sheath was 1.81+/-0.19 microm in thickness. The effect in group B was better than that of groups A and C (P> 0.05). Two months after the operation, the materials in groups B and C were completely degraded. The quantity of the regenerated nerves in group B confirmed by S-100 immunohistochemical observation and Bielschowslcy staining was more than that in group C(P<0.05) and close to that in group A. The regenerated nerve myelin sheath in group B was 2.15+/-0.27 microm in the thickness and was thicker than that in group C (P<0.05), but thinner than that in groups A and D (P<0.05)., Conclusion: PDLLA-T3 can repair the defect of rat sciatic nerve with satisfactory quantity and quality of regenerated nerves.

Objective: To investigate the histopathological changes in the liver and other organs after impact injury., Methods: The rabbits were impacted with a BIM-IV biological impacting machine at the xiphoid process. The severity of liver injury was graded and scored through gross anatomy. At the same time, the pathological changes in the liver, heart, and lung were observed by light and electron microscopes., Results: Light microscopy showed that the pathological changes in the liver were: 1) loss of normal structure, hemorrhage and distortion of hepatic lobules; 2) cloudy swelling, degeneration, vacuolation and necrosis of liver cells; 3) infiltration of neutrophils. The lungs were injured and there were liver cell emboli in the small pulmonary arteries. Electron microscopy showed that the ultrastructure of the liver cells was severely damaged and the cells had significant features of necrosis., Conclusions: The major pathomorphological changes in the liver after impact injury are hemorrhage and necrosis. They may be complicated by exfoliation of liver cells to hepatic sinusoids. These cells circulate with the blood to form emboli in the pulmonary blood vessels.

OBJECTIVE: The dynamic response of the heart during chest impact and the characteristics of heart injuries were investigated to further understand the mechanisms of heart impact injuries. METHODS: Eleven dogs and thirty-four rabbits were subjected to front thoracic impact with different impact velocities and compression response. The accelerated movement of thoracic wall during the impact period was monitored. The pathological examination of the injured heart was done and the dynamic responses and mechanisms of injuries were analyzed with mathematics models. RESULTS: The analysis of mathematics model and experimental results showed that the injury severity of heart was well correlated with the viscous criterion. The thoracic wall was involved in bi-directional movement of compression and expansion. The injured heart showed spotty or stripy hemorrhages in the ventricle endocardium. Light microscopic examination showed interstitial bleeding and rupture of the myocardial fibers in the contusion area. The biomechanical analysis indicated that there was a large deformation caused by the stress concentration on the lateral ventricle wall. CONCLUSIONS: There is a high speed and excessive deformation of the heart during the impact period, which might be the key mechanism of heart injury. The strong impact and press coming from both sternum and vertebral column and the rapid elevation of pressure in the ventricle are the main cause of deformation.