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Temperature-Dependent Compressive Deformation Behavior of Commercially Pure Iron Processed by ECAP

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Acta Metallurgica Sinica(English Letters) 2015年第5期28卷 531-541页

作者： Ying Yan Yue Qi qing-wei jiang Xiao-Wu Li Institute of Materials Physics and Chemistry College of Sciences Northeastern University College of Materials Science and Engineering Kunming University of Science and Technology Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University

To explore the temperature dependence of deformation behavior of BCC structural materials and the relevant effect of pre-annealing, commercially pure iron （CP Fe） produced by equal-channel angular pressing （ECAP） is selected as the experimental material. The influences of deformation temperature T and pre-annealing on deformation behavior, surface deformation characteristics and substructures of ECAP Fe were systematically studied. The results show that ECAP Fe undergoes a remarkable strain softening stage after a rapid strain hardening during uniaxial compression, and the softening degree and the yield strength avs first decrease and then increase with raising temperature. Pre-annealing at 400 ℃ effectively weakens the strain softening degree and increases trys. To understand the influence of deformation temperature on deformation behavior, as well as the relevant pre-annealing effect, deformation and damage characteristics and dislocation structures are studied in detail. In a word, the strain softening of ECAP Fe is associated not only with internal structural instability, but also with temperature, and pre-annealing at 400 ℃ improves high-temperature me- chanical properties of ECAP Fe.

关键词： ECAP Fe Uniaxiai compression High-temperature mechanical behavior Pre-annealing Deformation features Microstructure

Bone cement enhanced pedicle screw fixation combined with vertebroplasty for elderly patients with malignant spinal tumors

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Chinese Medical Journal 2013年第13期126卷 2495-2498页

作者： TAN jiang-wei SHEN Bing-hua DU wei LIU jiang-qing LU Shi-qiao Department of Spinal Surgery Yantaishan Hospital Yantai Shandong 264008 China

Background Older patients with malignant spinal tumors are difficult to treat because they have many co-morbidities including osteoporosis. The purpose of this research is to discuss the technique and clinical outcome of bone cement enhanced pedicle screw fixation combined with vertebroplasty （the Sandwich Procedure） for elderly patients with severe osteoporosis and malignant spinal tumors. Methods This study includes 28 consecutive elderly patients with malignant thoracic or lumbar spinal tumors. There were nine patients with myelomas, and 19 patients with metastatic bone tumors. The Sandwich Procedure began with curettage of the tumor and a vertebroplasty with bone cement （polymethyl methacrylate, PMMA）, followed by PMMA enhanced pedicle screw fixation. Patients were evaluated with the visual analogue scale （VAS）, oswestry disability index （ODI）, American Spinal Cord Injury Association （ASIA） neurological function classification, and the radiographic degree of kyphosis （Cobb angle）. Data were analyzed using paired t-test to compare the pre- and post-operative values. The complications, local recurrences, and the survival status were also recorded. Results There was no operative mortality, and the mean operative time was 210 minutes （range 150-250 minutes）. The average blood loss was 1550 ml （range 650-3300 ml）. The average amount of cement for vertebroplasty was 3.6 ml （range 3-5 ml）. The VAS, ODI, and ASIA scores were significantly improved after surgery （P 〈0.05）. However, we found no differences between the pre and post-operative Cobb angles. The shortest survival time was 3 months, and we found no evidence of local recurrence in this group of patients. Conclusion The Sandwich Procedure is a safe operation and provides symptomatic relief in these difficult patients, permitting further treatment with chemotherapy or radiotherapy.

关键词： Sandwich procedure, malignant spinal tumor, osteoporosis bone cement, pedicle screw

Endoscopic ultrasound features of autoimmune pancreatitis: The typical findings and chronic pancreatitis changes

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World Journal of Gastroenterology 2021年第42期27卷 7376-7386页

作者： Sheng-Yu Zhang Yun-Lu Feng Long Zou Xi Wu Tao Guo qing-wei jiang Qiang Wang Ya-Min Lai Shou-jiang Tang Ai-Ming Yang Department of Gastroenterology Peking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Division of Digestive Disease Department of MedicineUniversity of Mississippi Medical CenterJacksonMS 39216United States

BACKGROUND Few studies have fully described endoscopic ultrasound(EUS)features of newly diagnosed autoimmune pancreatitis(AIP)involving both typical findings and chronic pancreatitis(CP)*** typical EUS findings are prevalent in the diffuse type AIP but may not be as common for the focal type,and the differences between the diffuse and focal AIP need to be *** To demonstrate the EUS features of newly diagnosed AIP and the difference between diffuse and focal *** This retrospective single center study included 285 patients of newly diagnosed type 1 AIP following the international consensus diagnostic criteria,with the EUS procedures accomplished before corticosteroid *** explored the EUS features and compared the typical AIP and CP features between the diffuse and focal AIP *** Rosemont criteria were employed for CP features definition and CP change level *** For the typical AIP features,there were significantly more patients in the diffuse group with bile duct wall thickening(158 of 214 cases,73.4%vs 37 of 71 cases,52.1%,P=0.001)and peripancreatic hypoechoic margin(76 of 214 cases,35.5%vs 5 of 71 cases,7.0%,P<0.001).For the CP features,there were significantly more patients in the focal group with main pancreatic duct dilation(30 of 214 cases,14.0%vs 18 of 71 cases,25.3%,P=0.03).The cholangitis-like changes were more prevalent in the focal cases with pancreatic head *** CP change level was relatively limited for newly diagnosed AIP cases in both *** This study demonstrated the difference in the typical AIP and CP features between diffuse and focal AIP and indicated the limited CP change level in newly diagnosed AIP.

关键词： Endoscopic ultrasound Autoimmune pancreatitis Rosemont criteria Chronic pancreatitis

Genetic counseling, prenatal screening and diagnosis of Down syndrome in the second trimester in women of advanced maternal age： a prospective study

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Chinese Medical Journal 2013年第11期126卷 2007-2010页

作者： QI qing-wei jiang Yu-lin ZHOU Xi-ya LIU Jun-tao YIN Jie BIAN Xu-ming Department of Obstetrics and Gynecology Chinese Academy ofMedical Science Peking Union Medical College Peking UnionMedical College Hospital Beijing 100730 China

Background The incidence of autosomal trisomy in livebirths is strongly dependent on maternal age. Special consideration is given to the provision of prenatal screening and cytogenetic testing to women of advanced maternal age （AMA）. The aim of this study was to evaluate the effectiveness of second trimester prenatal screening and amniocentesis for Down syndrome （DS） and compare the trends of choice of screening and amniocentesis among AMA women. Methods A total of 5404 AMA patients with natural singleton pregnancy were recruited for this prospective study from January 2008 to December 2010. The gestational weeks were from 15 weeks to 20~6 weeks. The patients referred were grouped into a screening group （2107 cases） and an amniocentesis group （3297 cases） by their own decision. The prevalence of DS was compared between the two groups by chi-square test. Choice rates for each maternal age with trends were compared by regression analysis. Results There were 18 cases of fetal DS detected in the screening group with a prevalence of 8.54%o （18/2107）. Twenty- five cases of fetal DS were diagnosed in the amniocentesis group with a prevalence of 7,58%0 （25/3297）. No statistical difference was observed in the prevalence of DS between the screening and amniocentesis group （P=0.928）. The invasive testing rate for DS in the amniocentesis group was 5.54 times higher than that of the screening group （1/131.88 vs. 1/23.78）. With the increase of the maternal age, the choice of amniocentesis increased while the choice of the screening showed an opposite trend. The choice of the AMA women between the screening and amniocentesis was significantly age relevant （P=0.012）. Conclusions The second trimester serum screening age alone to screen for DS. We suggest educating screening and amniocentesis options. in combination with maternal age was more effective than maternal the patients by recommending AMA women be informed of both

关键词： genetic counseling advanced maternal age Down syndrome prenatal screening genetic amniocentesis second trimester

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia Yu Wang Chun Cheng Yang qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

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基于信息论测度的旁路泄露分析研究

海军工程大学学报 2016年第6期28卷 93-96,106页

作者：周大伟欧庆于江山海军工程大学信息安全系武汉430033 海军工程大学训练部武汉430033

针对密码芯片基于旁路通道的敏感信息泄露度量问题,以信息论测度理论为基础,通过综合运用统计信号处理、互信息等手段,提出了一种基于信息论测度的旁路泄露分析方法。该旁路泄露分析方法无需预先了解密码芯片的实现细节,并具备对高阶旁... 详细信息

针对密码芯片基于旁路通道的敏感信息泄露度量问题,以信息论测度理论为基础,通过综合运用统计信号处理、互信息等手段,提出了一种基于信息论测度的旁路泄露分析方法。该旁路泄露分析方法无需预先了解密码芯片的实现细节,并具备对高阶旁路泄露进行度量的能力。实验表明:该分析方法能够以较小的代价实现有效的旁路泄露检测。

关键词：密码芯片旁路攻击互信息

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

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Neural Regeneration Research 2025年第3期20卷 779-793页

作者： Guangyong Zhang qing Yao Chubing Long Pengcheng Yi Jiali Song Luojia Wu wei Wan Xiuqin Rao Yue Lin Gen wei Jun Ying Fuzhou Hua Department of Anesthesiology the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Key Laboratory of Anesthesiology of jiangxi Province NanchangJiangxi ProvinceChina

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

关键词： blood–brain barrier macrophages monocytes multiple sclerosis neuroinflammation review therapy

Microstructure Evolution and Mechanism of Strength Development of Fly Ash Paste

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 152-163页

作者： MA Shuzhao WU Shunchuan HUANG Mingqing CHENG Haiyong jiang Guanzhao NIU Yonghui LIU Zemin SUN wei Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Zijin School of Ge-ology and Mining Fuzhou UniversityFuzhou 350108China

Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash *** conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the *** mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were *** results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased *** the content exceeded 4%,the rate of increase in strength *** on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping *** activation effect was poor for long-term strength after 28 *** CaO content did not significantly affect the degree of activation *** maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the *** activators also corroded the surface of the fly ash particles,resulting in a pozzolanic *** active substances in fly ash were released efficiently,and hydration was *** pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.

关键词： paste filling fly ash activator unconfined compressive strength microstructure hydration simulation

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping Yu Emily Choi Michael Qjiang Ling wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment