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Coercivity mechanism of La-Nd-Fe-B films with Y spacer layer
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作者 马俊 赵晓天 +4 位作者 刘伟 李阳 刘龙 赵新国 张志东 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期138-143,共6页
The effect of the Y spacer layer on the phase composition,coercivity,and magnetization reversal processes of La-Nd-Fe-B films has been investigated.The addition of a 10 nm Y spacer layer increases the coercivity of th... The effect of the Y spacer layer on the phase composition,coercivity,and magnetization reversal processes of La-Nd-Fe-B films has been investigated.The addition of a 10 nm Y spacer layer increases the coercivity of the film to 1.36 T at 300 K and remains 0.938 T at 380 K.As the thickness of the Y spacer layer increases,Y participates in the formation of the main phase in the film,and further regulates the formation of La-B phases.The results of the first-order reversal curve(FORC)and micromagnetic fitting show that the coercivity of all the films is dominated by nucleation mechanism.The c-axis preferred orientation,good magnetic microstructure parameters and the largest dipole interaction enhance the coercivity.Therefore,the introduction of the Y spacer layer can be an effective way to improve the coercivity of La-Nd-Fe-B film over a wide temperature range of 150 K-380 K. 展开更多
关键词 La-Nd-(Y)-Fe-B films magnetization reversal mechanisms COERCIVITY MULTILAYERS
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Long-term prognosis and its associated predictive factors in patients with eosinophilic gastroenteritis
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作者 Kai-Wen Li Ge-Chong Ruan +8 位作者 Shuang liu Tian-Ming Xu Ye Ma wei-Xun Zhou wei liu Peng-Yu Zhao Zhi-Rong Du Ji Li Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第2期146-157,共12页
BACKGROUND Eosinophilic gastroenteritis(EGE)is a chronic recurrent disease with abnormal eosinophilic infiltration in the gastrointestinal tract.Glucocorticoids remain the most common treatment method.However,disease ... BACKGROUND Eosinophilic gastroenteritis(EGE)is a chronic recurrent disease with abnormal eosinophilic infiltration in the gastrointestinal tract.Glucocorticoids remain the most common treatment method.However,disease relapse and glucocorticoid dependence remain notable problems.To date,few studies have illuminated the prognosis of EGE and risk factors for disease relapse.AIM To describe the clinical characteristics of EGE and possible predictive factors for disease relapse based on long-term follow-up.METHODS This was a retrospective cohort study of 55 patients diagnosed with EGE admitted to one medical center between 2013 and 2022.Clinical records were collected and analyzed.Kaplan-Meier curves and log-rank tests were conducted to reveal the risk factors for long-term relapse-free survival(RFS).RESULTS EGE showed a median onset age of 38 years and a slight female predominance(56.4%).The main clinical symptoms were abdominal pain(89.1%),diarrhea(61.8%),nausea(52.7%),distension(49.1%)and vomiting(47.3%).Forty-three(78.2%)patients received glucocorticoid treatment,and compared with patients without glucocorticoid treatments,they were more likely to have elevated serum immunoglobin E(IgE)(86.8%vs 50.0%,P=0.022)and descending duodenal involvement(62.8%vs 27.3%,P=0.046)at diagnosis.With a median follow-up of 67 mo,all patients survived,and 56.4%had at least one relapse.Six variables at baseline might have been associated with the overall RFS rate,including age at diagnosis<40 years[hazard ratio(HR)2.0408,95%confidence interval(CI):1.0082–4.1312,P=0.044],body mass index(BMI)>24 kg/m^(2)(HR 0.3922,95%CI:0.1916-0.8027,P=0.014),disease duration from symptom onset to diagnosis>3.5 mo(HR 2.4725,95%CI:1.220-5.0110,P=0.011),vomiting(HR 3.1259,95%CI:1.5246-6.4093,P=0.001),total serum IgE>300 KU/L at diagnosis(HR 0.2773,95%CI:0.1204-0.6384,P=0.022)and glucocorticoid treatment(HR 6.1434,95%CI:2.8446-13.2676,P=0.003).CONCLUSION In patients with EGE,younger onset age,longer disease course,vomiting and glucocorticoid treatment were risk factors for disease relapse,whereas higher BMI and total IgE level at baseline were protective. 展开更多
关键词 Eosinophilic gastroenteritis PROGNOSIS RELAPSE GLUCOCORTICOID Glucocorticoid dependence
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A Joint Entity Relation Extraction Model Based on Relation Semantic Template Automatically Constructed
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作者 wei liu Meijuan Yin +1 位作者 Jialong Zhang Lunchong Cui 《Computers, Materials & Continua》 SCIE EI 2024年第1期975-997,共23页
The joint entity relation extraction model which integrates the semantic information of relation is favored by relevant researchers because of its effectiveness in solving the overlapping of entities,and the method of... The joint entity relation extraction model which integrates the semantic information of relation is favored by relevant researchers because of its effectiveness in solving the overlapping of entities,and the method of defining the semantic template of relation manually is particularly prominent in the extraction effect because it can obtain the deep semantic information of relation.However,this method has some problems,such as relying on expert experience and poor portability.Inspired by the rule-based entity relation extraction method,this paper proposes a joint entity relation extraction model based on a relation semantic template automatically constructed,which is abbreviated as RSTAC.This model refines the extraction rules of relation semantic templates from relation corpus through dependency parsing and realizes the automatic construction of relation semantic templates.Based on the relation semantic template,the process of relation classification and triplet extraction is constrained,and finally,the entity relation triplet is obtained.The experimental results on the three major Chinese datasets of DuIE,SanWen,and FinRE showthat the RSTAC model successfully obtains rich deep semantics of relation,improves the extraction effect of entity relation triples,and the F1 scores are increased by an average of 0.96% compared with classical joint extraction models such as CasRel,TPLinker,and RFBFN. 展开更多
关键词 Natural language processing deep learning information extraction relation extraction relation semantic template
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Exploring non-curative endoscopic submucosal dissection:Current treatment optimization and future indication expansion
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作者 Yi-Nong Zhu Xiang-Lei Yuan +4 位作者 wei liu Yu-Hang Zhang Yi Mou Bing Hu Lian-Song Ye 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1257-1260,共4页
The increasing popularity of endoscopic submucosal dissection(ESD)as a treatment for early gastric cancer has highlighted the importance of quality assessment in achieving curative resections.This article emphasizes t... The increasing popularity of endoscopic submucosal dissection(ESD)as a treatment for early gastric cancer has highlighted the importance of quality assessment in achieving curative resections.This article emphasizes the significance of evaluating ESD quality,not only for curative cases but also for non-curative ones.Postoperative assessment relies on the endoscopic curability(eCura)classification,but management strategies for eCuraC-1 tumour with a positive horizontal margin are unclear.Current research primarily focuses on comparing additional surgical procedures in high-risk patients,while studies specifically targeting eCuraC-1 patients are limited.Exploring management strategies and follow-up outcomes for such cases could provide valuable insights.Furthermore,the application of molecular imaging using near-infrared fluorescent tracers holds promise for precise tumour diagnosis and navigation,potentially impacting the management of early-stage gastric cancer patients.Advancing research in these areas is essential for improving the overall efficacy of endoscopic techniques and refining treatment indications. 展开更多
关键词 Early gastric cancer Endoscopic submucosal dissection Quality control Noncurative endoscopic submucosal dissection Near-infrared fluorescent tracer
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新药改善自体造血干细胞移植治疗复发或难治性霍奇金淋巴瘤患者的生存分析
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作者 谢婷 刘慧敏 +5 位作者 山丹丹 刘薇 王轶 黄文阳 邱录贵 邹德慧 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第2期76-80,共5页
目的:探讨新药时代自体造血干细胞移植(autologous hematopoietic stem cell transplantation,ASCT)治疗复发或难治性(relapse or refractory,R/R)经典型霍奇金淋巴瘤(classical Hodgkin's lymphoma,cHL)的疗效。方法:回顾性分析201... 目的:探讨新药时代自体造血干细胞移植(autologous hematopoietic stem cell transplantation,ASCT)治疗复发或难治性(relapse or refractory,R/R)经典型霍奇金淋巴瘤(classical Hodgkin's lymphoma,cHL)的疗效。方法:回顾性分析2010年1月至2022年12月在中国医学科学院血液病医院诊治的56例挽救治疗敏感、序贯ASCT治疗的R/R cHL患者,根据挽救治疗是否包含维布妥昔单抗(brentuximab vedotin,BV)或程序性死亡受体1(programmed death-1,PD-1)抑制剂分为新药组32例和非新药组24例,分析两组患者的临床特征及疗效,使用Kaplan-Meier法进行生存分析。结果:56例患者中男性35例,女性21例,中位移植年龄29(11~55)岁。中位随访时间56(2~137)个月,移植后预期5年总生存(overall survival,OS)率和无进展生存(progression-free survival,PFS)率分别为94.3%和75.8%。新药组患者的5年PFS更优(90.1%vs.59.1%,HR=0.23,95%CI:0.07~0.71,P=0.011),但OS差异无统计学意义(93.5%vs.95.5%,HR=1.2,95%CI:0.14~10.34,P=0.873)。结论:对于挽救治疗敏感的R/R cHL患者,ASCT仍然是标准的巩固治疗策略。新药在移植前、后的应用可进一步提高ASCT治疗R/R cHL患者的生存。 展开更多
关键词 霍奇金淋巴瘤 造血干细胞移植 维布妥昔单抗 PD-1抑制剂
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Ankylosing spondylitis coexisting with Clonorchis sinensis infection: A case report
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作者 Tian-Xin Yi wei liu +2 位作者 Wen-Fei Leng Xiao-Chuan Wang Liang Luo 《World Journal of Clinical Cases》 SCIE 2024年第5期1018-1024,共7页
BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune respons... BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune responses.Numerous studies have investigated links between AS and various infections-bacterial,viral,fungal,and other microorganism infections.However,limited attention has been given to the association between AS and Clonorchis sinensis(C.sinensis)infection.CASE SUMMARY A 27-year-old male with a 10-yr history of AS presented to our hospital with inflammatory lower back pain as the primary manifestation.Ten years ago,the patient had achieved a stable condition after treatment with biological agents.However,he experienced a recurrence of lumbosacral pain with an unexplained cause 10 d before hospital admission.A lumbosacral magnetic resonance imaging(MRI)scan revealed bone marrow edema in the left sacroiliac joint,and laboratory indicators were elevated.Moreover,the presence of C.sinensis eggs was detected in the stool.The patient was prescribed praziquantel,resulting in the disap-pearance of C.sinensis eggs in subsequent routine stool tests and relief from lumbosacral pain.A follow-up MRI scan performed after 4 months revealed a reduction in bone marrow edema around the left sacroiliac joint.CONCLUSION C.sinensis infections could potentially trigger the exacerbation of AS.Clinicians should pay attention to investigating the presence of infections.INTRODUCTION Ankylosing spondylitis(AS)is a chronic inflammatory and rheumatic disease resulting from an imbalance between innate and acquired immune responses[1].While it can affect any part of the spine,its primary symptoms are persistent back pain and stiffness in the lower back and pelvis.The prevalence of AS per 10000 individuals is 23.8 in Europe,31.9 in North America,16.7 in Asia,10.2 in Latin America,and 7.4 in Africa[2].Infections commonly occur in the first 3 months and may act as potential triggers for the first symptoms of AS,often manifesting as gastrointestinal,urinary tract,and respiratory infections of microbiological origin[3,4].Clonorchis sinensis(C.sinensis)infection is a severe parasitic disease affecting millions globally,especially prevalent in China,South Korea,the Far East of Russia,and Vietnam,with an estimated 15 million cases[5].Transmission occurs through the consumption of undercooked freshwater fish containing metacercariae.Adult C.sinensis parasites then establish themselves within the human hepatobiliary system[6].C.sinensis infection triggers the activation of sphingosine 1-phosphate receptor 2,leading to the injury and fibrosis of the hepatobiliary[7].Recent research in a rat model found that C.sinensis infection increases the risk of hepatocellular carcinoma by stimulating hepatic progenitor cell proliferation[8].Complications of C.sinensis infection include cholestasis,cholangitis,biliary system fibrosis,and in severe cases,the development of cholangiocarcinoma[9].Consequently,the primary preventive measure is to abstain from consuming raw or undercooked freshwater fish.Praziquantel is the recommended and effective treatment for this infection[10].While there is existing literature on the coexistence of AS and parasitic infections,there is limited research specifically addressing the simultaneous presence of AS and C.sinensis infection.This case report details a rare scenario of AS coexisting with C.sinensis infection,underscoring the potential impact of C.sinensis infection on AS disease activity. 展开更多
关键词 Ankylosing spondylitis Clonorchis sinensis Parasites INFECTION Case report
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The Influence of Acid on the RockMechanical Characteristics of Deep Shale in theWujiaping Formation
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作者 Hao Zhang Yan Zhang +2 位作者 wei liu Ximin Zhang Xiang liu 《Energy Engineering》 EI 2024年第1期27-42,共16页
The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to ... The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation,based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation.The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion.And a 15%concentration of hydrochloric acid can effectively dissolve shale.Furthermore,the degree of acid-etching reaction is highly variable because of the different carbonate content,which reveals the strong inhomogeneity of the shale system in the Wujiaping Group reservoir section.After the acid interacted with the shale rock samples,the triaxial compressive strength,elastic modulus,and Poisson’s ratio of shale decreased.Moreover,the evaluation of the effect after acid fracturing simulated by fracturing software revealed that the smaller the value of elastic modulus in shale-based reservoirs,the more favorable the fracture volume modification.This discovery not only provides a theoretical basis for the expansion and extension patterns of acid-fracturing in carbonaceous shale formations but also offers research methods and theoretical insights for the fundamental exploration of other deep-seated oil and gas resources. 展开更多
关键词 SHALE acid fracturing macro characteristics microscopic characteristics mechanical properties
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Research on Sleeve Grouting Density Detection Based on the Impact Echo Method
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作者 Pu Zhang Yingjun Li +5 位作者 Xinyu Zhu Shizhan Xu Pinwu Guan wei liu Yanwei Guo Haibo Wang 《Structural Durability & Health Monitoring》 EI 2024年第2期143-159,共17页
Grouting defects are an inherent challenge in construction practices,exerting a considerable impact on the operational structural integrity of connections.This investigation employed the impact-echo technique for the ... Grouting defects are an inherent challenge in construction practices,exerting a considerable impact on the operational structural integrity of connections.This investigation employed the impact-echo technique for the detection of grouting anomalies within connections,enhancing its precision through the integration of wavelet packet energy principles for damage identification purposes.A series of grouting completeness assessments were meticulously conducted,taking into account variables such as the divergent material properties of the sleeves and the configuration of adjacent reinforcement.The findings revealed that:(i)the energy distribution for the highstrength concrete cohort predominantly occupied the frequency bands 42,44,45,and 47,whereas for other groups,it was concentrated within the 37 to 40 frequency band;(ii)the delineation of empty sleeves was effectively discernible by examining the wavelet packet energy ratios across the spectrum of frequencies,albeit distinguishing between sleeves with 50%and full grouting density proved challenging;and(iii)the wavelet packet energy analysis yielded variable detection outcomes contingent on the material attributes of the sleeves,demonstrating heightened sensitivity when applied to ultrahigh-performance concrete matrices and GFRP-reinforced steel bars. 展开更多
关键词 Prefabricated building steel grouting sleeve impact echo method wavelet packet energy grouted defect
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Scinderin promotes glioma cell migration and invasion via remodeling actin cytoskeleton
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作者 Xin Lin Zhao Zhao +1 位作者 Shu-Peng Sun wei liu 《World Journal of Clinical Oncology》 2024年第1期32-44,共13页
BACKGROUND Glioma is one of the most common intracranial tumors,characterized by invasive growth and poor prognosis.Actin cytoskeletal rearrangement is an essential event of tumor cell migration.The actin dynamics-rel... BACKGROUND Glioma is one of the most common intracranial tumors,characterized by invasive growth and poor prognosis.Actin cytoskeletal rearrangement is an essential event of tumor cell migration.The actin dynamics-related protein scinderin(SCIN)has been reported to be closely related to tumor cell migration and invasion in several cancers.AIM To investigate the role and mechanism of SCIN in glioma.METHODS The expression and clinical significance of SCIN in glioma were analyzed based on public databases.SCIN expression was examined using real-time quantitative polymerase chain reaction and Western blotting.Gene silencing was performed using short hairpin RNA transfection.Cell viability,migration,and invasion were assessed using cell counting kit 8 assay,wound healing,and Matrigel invasion assays,respectively.F-actin cytoskeleton organization was assessed using F-actin staining.RESULTS SCIN expression was significantly elevated in glioma,and high levels of SCIN were associated with advanced tumor grade and wild-type isocitrate dehydrogenase.Furthermore,SCIN-deficient cells exhibited decreased proliferation,migration,and invasion in U87 and U251 cells.Moreover,knockdown of SCIN inhibited the RhoA/focal adhesion kinase(FAK)signaling to promote F-actin depolymerization in U87 and U251 cells.CONCLUSION SCIN modulates the actin cytoskeleton via activating RhoA/FAK signaling,thereby promoting the migration and invasion of glioma cells.This study identified the cancer-promoting effect of SCIN and provided a potential therapeutic target for the treatment of glioma. 展开更多
关键词 GLIOMA Scinderin Actin cytoskeleton RhoA/FAK signaling DEPOLYMERIZATION
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Mapping of Purple Gene in Spears of Asparagus(Asparagus officinalis L.)
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作者 Tao liu Wenlai REN +4 位作者 Yuqin LIANG Yubo WANG wei liu Xing WANG Yanpo CAO 《Agricultural Biotechnology》 2024年第1期5-8,共4页
[Objectives]This study was conducted to find out regulatory genes related to purple in spears of asparagus(Asparagus officinalis L.).[Methods]The stable asparagus inbred line JX1513-5(the base of the spear is purple)a... [Objectives]This study was conducted to find out regulatory genes related to purple in spears of asparagus(Asparagus officinalis L.).[Methods]The stable asparagus inbred line JX1513-5(the base of the spear is purple)and JLV1718-7(the base of the spear is green)were used as parents to study the genetic law of purple/green traits in their offspring.[Results]The results showed that the purple in the basal part of asparagus spear was controlled by a pair of alleles,and purple was dominant over green.The F 2 segregation population was resequenced by the bulk segregation analysis(BSA)method,and the purple trait in the basal part of asparagus spear was located in the interval of 24.51-25.08 Mb on Chr07 chromosome,which included 47 genes.According to the annotation information,three candidate genes were screened out:LOC109849403,LOC109849430 and LOC109849442.The candidate genes were verified by real-time fluorescence quantitative PCR(qRT-PCR),and finally LOC109849442 was obtained as the candidate gene for controlling the purple/green trait in the basal part of asparagus spear.[Conclusions]This study lays a foundation for the breeding of new asparagus varieties and molecular marker-assisted breeding. 展开更多
关键词 ASPARAGUS Anthocyanins Gene mapping PURPLE
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共同富裕视域下的乡村治理:逻辑转换、体系革新与路径选择 被引量:3
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作者 刘伟 吴兵兵 《中央社会主义学院学报》 2023年第1期147-160,共14页
在第二个百年实现全面建成社会主义现代化国家的新征程中,解决乡村相对贫困、提升乡村发展水平和实现乡村治理现代化,营造一个能够充分保障农民获得感、幸福感以及安全感的乡村善治环境,已经成为破解我国社会主要矛盾、致力共同富裕不... 在第二个百年实现全面建成社会主义现代化国家的新征程中,解决乡村相对贫困、提升乡村发展水平和实现乡村治理现代化,营造一个能够充分保障农民获得感、幸福感以及安全感的乡村善治环境,已经成为破解我国社会主要矛盾、致力共同富裕不可或缺的、关键的“最后一公里”。在共同富裕视域下,乡村治理将发生相应的逻辑转换:在治理价值上,从秩序取向拓展为兼顾秩序与发展取向的综合取向;在治理内容上,从生产、行政、社会建设等局部治理拓展为政治、经济、社会、文化、生态的全方位治理;在治理主体上,从乡镇政府、村庄主体等有限主体拓展为市场主体、社会组织和不同层级政府力量的多元主体;在治理场景上,从城乡分离拓展为城乡融合。在此过程中,我国的乡村治理体系将从改革开放以来形成的“乡政村治”架构,发展为自治、法治和德治“三治融合”的制度构造。下一步,乡村治理现代化的实践,需要统合理念变革、制度优化、主体协同以及民生服务,全方位破解乡村基层治理的瓶颈,释放、激发乡村潜力和活力,走出一条以共同富裕促进乡村现代化和善治的道路。 展开更多
关键词 共同富裕 乡村治理 善治 逻辑转换 体系革新 路径选择
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Frequency domain polarization weighted ESPRIT method for bearing angle 被引量:2
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作者 wei liu Shengchun Piao +2 位作者 Junyuan Guo Qingxin Meng Hanhao Zhu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期769-775,共7页
The signal to noise ratio(SNR) of seismic waves is usually very low after long distance transmission. For this condition, to improve the bearing estimation capability in the low SNR,a frequency domain polarization wei... The signal to noise ratio(SNR) of seismic waves is usually very low after long distance transmission. For this condition, to improve the bearing estimation capability in the low SNR,a frequency domain polarization weighted ESPRIT method using a single vector device is proposed. The frequency domain polarization parameters extracted from the signals are used to design the weighted function which is applied to the received signals. The bearing angle and the target frequency are estimated through ESPRIT using the weighted signals. The simulation and experiment results show that the presented method can obtain accurate estimation values under the low SNR with little prior information. 展开更多
关键词 ESPRIT方法 加权函数 频域 极化 方位角 ESPRIT法 信号估计 低信噪比
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超声造影参数及MVD对宫颈癌的鉴别诊断及预后评估价值 被引量:5
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作者 黄蕊 韦柳 秦卫红 《实用癌症杂志》 2023年第1期39-41,共3页
目的 探讨超声造影参数及MVD对宫颈癌的鉴别诊断及预后评估价值。方法 选取96例宫颈癌患者(研究组)和100宫颈良性肿瘤患者(对照组),其中宫颈癌患者又分为早期组30例和中晚期组66例,比较组间患者的超声造影参数及MVD等差异。结果 PI、PI/... 目的 探讨超声造影参数及MVD对宫颈癌的鉴别诊断及预后评估价值。方法 选取96例宫颈癌患者(研究组)和100宫颈良性肿瘤患者(对照组),其中宫颈癌患者又分为早期组30例和中晚期组66例,比较组间患者的超声造影参数及MVD等差异。结果 PI、PI/PIc、AUC、MTT及MVD在对照组、早期组及中晚期组中逐渐升高(P<0.05),而TTP则在对照组、早期组及中晚期组中逐渐降低(P<0.05);宫颈鳞癌患者PI/PIc、AUC与MVD均呈正相关(P<0.05),而TTP与MVD呈负相关(P<0.05)。生存组的PI、PI/PIc、AUC、MTT及MVD均低于死亡组(P<0.05),而TTP则高于死亡组(P<0.05)。结论 超声造影及MVD可在一定程度上作为宫颈癌鉴别诊断和临床分期的判断指标,同时可为其预后评估提供帮助,值得临床推广应用。 展开更多
关键词 宫颈癌 鉴别诊断 超声造影 微血管密度 预后
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An improved global-direction stencil based on the face-area-weighted centroid for the gradient reconstruction of unstructured finite volume methods 被引量:2
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作者 孔令发 董义道 +1 位作者 刘伟 张怀宝 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期109-130,共22页
The accuracy of unstructured finite volume methods is greatly influenced by the gradient reconstruction, for which the stencil selection plays a critical role. Compared with the commonly used face-neighbor and vertex-... The accuracy of unstructured finite volume methods is greatly influenced by the gradient reconstruction, for which the stencil selection plays a critical role. Compared with the commonly used face-neighbor and vertex-neighbor stencils, the global-direction stencil is independent of the mesh topology, and characteristics of the flow field can be well reflected by this novel stencil. However, for a high-aspect-ratio triangular grid, the grid skewness is evident, which is one of the most important grid-quality measures known to affect the accuracy and stability of finite volume solvers. On this basis and inspired by an approach of using face-area-weighted centroid to reduce the grid skewness, we explore a method by combining the global-direction stencil and face-area-weighted centroid on high-aspect-ratio triangular grids, so as to improve the computational accuracy. Four representative numerical cases are simulated on high-aspect-ratio triangular grids to examine the validity of the improved global-direction stencil. Results illustrate that errors of this improved methods are the lowest among all methods we tested, and in high-mach-number flow, with the increase of cell aspect ratio, the improved global-direction stencil always has a better stability than commonly used face-neighbor and vertex-neighbor stencils. Therefore, the computational accuracy as well as stability is greatly improved, and superiorities of this novel method are verified. 展开更多
关键词 unstructured finite volume methods improved global-direction stencil grid skewness face-area-weighted centroid
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Research on the Ecological Wisdom of Traditional Dwellings of the Liangshan Yi Nationality Based on Regional Climate
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作者 Qin Lai wei liu Xing Li 《Journal of Building Construction and Planning Research》 2023年第2期50-68,共19页
As a typical building with ethnic and regional characteristics in southwest Chi-na, its construction skills contain rich local ecological wisdom. The detailed analysis of the climatic and geomorphological features of ... As a typical building with ethnic and regional characteristics in southwest Chi-na, its construction skills contain rich local ecological wisdom. The detailed analysis of the climatic and geomorphological features of the Liangshan Yi nationality area shows that the thermal mass effect is the first choice for the passive adjustment strategy of residential dwellings. This study focuses on the typical representatives of traditional dwellings in Meigu County, analyzing the wisdom of ecological construction to improve the thermal mass effects of res-idential buildings at the macro (village), moderate (courtyard), and micro (building unit) levels. Based on this analysis, the study summarizes the “genetic factor library” of the ecological construction mode of traditional Yi residential dwellings. Finally, the measured data of the residential thermal environment and the simulation data of Ecotect software are used to study and judge the logic behind its ecological construction wisdom. The results show that the tradi-tional dwellings of the Yi nationality in Liangshan have six aspects of local en-vironmental knowledge to improve the thermal mass effects performance of buildings. The winter thermal environment of the house is comfortable, and the heat is sufficient;Rammed earth materials in residential buildings have more potent, powerful, and robust thermal mass effects performance than stone slabs and wooden boards. 展开更多
关键词 Climate Adaptability Liangshan Yi Nationality Traditional Dwelling Ecological Intelligence
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超声引导下经支气管针吸活检在纵隔囊肿诊治中的应用(附4例报告)
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作者 柳威 王咏雪 +4 位作者 李芸 吴怀球 陈令佳 刘志光 张卫东 《中国内镜杂志》 2023年第4期86-90,共5页
目的 总结超声引导下经支气管针吸活检(EBUS-TBNA)在纵隔囊肿治疗中的应用,以提高临床医生的认识。方法 回顾性分析该院4例接受EBUS-TBNA诊治的纵隔囊肿患者的临床资料,并复习EBUS-TBNA诊治纵隔囊性病变应用的相关文献,总结其临床应用... 目的 总结超声引导下经支气管针吸活检(EBUS-TBNA)在纵隔囊肿治疗中的应用,以提高临床医生的认识。方法 回顾性分析该院4例接受EBUS-TBNA诊治的纵隔囊肿患者的临床资料,并复习EBUS-TBNA诊治纵隔囊性病变应用的相关文献,总结其临床应用及常见并发症。结果 4例纵隔囊性病变经气道内超声均可明确囊肿的诊断,通过对其囊液的分析,2例能够明确囊肿来源,1例出现了严重的感染相关并发症。结论 EBUS-TBNA可以作为纵隔囊性病变的有效诊断和治疗工具,但有可能出现严重的感染相关并发症,临床应用过程中,应选择合适的患者,严格把握无菌原则。 展开更多
关键词 超声引导下经支气管针吸活检 纵隔囊肿 诊断 治疗 并发症
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TeV cosmic-ray proton and helium spectra in the myriad model Ⅱ
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作者 wei liu Pierre Salati Xuelei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第1期15-27,共13页
Recent observations show that the spectra of cosmic ray nuclei start to harden above ~ 102 GeV, which contradicts the conventional steady-state cosmic ray model. We had suggested that this anomaly is due to the propa... Recent observations show that the spectra of cosmic ray nuclei start to harden above ~ 102 GeV, which contradicts the conventional steady-state cosmic ray model. We had suggested that this anomaly is due to the propagation effect of cosmic rays released from local young cosmic ray sources; the total flux of cosmic rays should be computed with the Myriad Model, where a contribution from sources in the local catalog is added to the background. However, although the hardening could be elegantly explained in this model, the model parameters obtained from the fit are skewed toward a region with fast diffusion and a low supernova rate in the Galaxy, in disagreement with other observations. We further explore this model in order to set up a concordant picture. Two possible improvements related to cosmic ray sources are considered. First, instead of the usual axisymmetric disk model, we examine a spiral model for the source distribution. Second, for nearby and young sources which are necessary to explain the hardening, we allow for an energy-dependent escape. We find that a major improvement comes from incorporating an energy-dependent escape time for local sources, and with both modifications not only are the cosmic ray proton and helium anomalies resolved, but also the parameters attain values in a reasonable range compatible with other analyses. 展开更多
关键词 射线模型 宇宙线 氦异常 光谱 质子 TEV 宇宙射线 逃逸时间
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AModel for the Optimization of the Shale Gas HorizontalWell Section Based on the Combination of Different Weighting Methods in the Frame of the Game Theory
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作者 Minxuan Li Jing Sun +5 位作者 Dehua liu Yang Li Kuidong Li wei liu Jialin Xiao Jiani Hu 《Fluid Dynamics & Materials Processing》 EI 2020年第5期993-1005,共13页
Existing“evaluation indicators”are selected and combined to build a model to support the optimization of shale gas horizontal wells.Towards this end,different“weighting methods”,including AHP and the so-called ent... Existing“evaluation indicators”are selected and combined to build a model to support the optimization of shale gas horizontal wells.Towards this end,different“weighting methods”,including AHP and the so-called entropy method,are combined in the frame of the game theory.Using a relevant test case for the implementation of the model,it is shown that the horizontal section of the considered well is in the middle sweet spot area with good physical properties and fracturing ability.In comparison with the FSI(flow scanner Image)gas production profile,the new model seems to display better abilities for the optimization of horizontal wells. 展开更多
关键词 Combination weight well section sweet spot AHP entropy method evaluation model
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Fracture Statistics Dominated by Hot-Cutting Defect and Deviation from Weibull Distribution
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作者 Chao Zeng Chunqing Wang +3 位作者 Yanhong Tian Chunjin Hang wei liu Rong An 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期41-48,共8页
This paper characterizes the rarely noticeable hot-cutting defect and statistically models the fracture governed by this new type defect. The morphology of the defect on fired ceramic is examined and quantitatively fe... This paper characterizes the rarely noticeable hot-cutting defect and statistically models the fracture governed by this new type defect. The morphology of the defect on fired ceramic is examined and quantitatively featured through comparing the fracture strength governed by intrinsic defect and hot-cutting defect. Weibull distribution is utilized to fit the observed strength data and chi-square goodness-of-fit test is conducted to analyze the deviation. Kernel density estimation is introduced to explore the underlying strength distribution dominated by hot-cutting defect. Based on the shape information from kernel density estimating,gamma and lognormal distribution are compared and the hot-cutting defect governing fracture statistics is finally confirmed by chisquare test. Results show that the newly-defined hot-cutting defect is more dangerous than the intrinsic defect and the priori Weibull distribution fails to describe the fracture statistic governed by the edge defect while the lognormal with a slightly right skewed shape fits it very well. 展开更多
关键词 hot-cutting defect deviation from Weibull Kernel density estimation lognormal distribution
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采用还原-磁化焙烧法从高铁锌焙砂中选择性浸出锌
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作者 张添富 韩俊伟 +4 位作者 刘森 刘维 李琛 焦芬 覃文庆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第11期3514-3528,I0001,共16页
为实现高铁锌焙砂中锌的选择性浸出,提出一种将还原焙烧与磁化焙烧相结合以强化铁酸锌选择性分解的新工艺。通过热力学分析和焙烧实验,详细研究铁酸锌的分解机理。结果表明,在8%CO(体积分数)、750℃、50%CO/(CO+CO_(2))(体积分数)和90 ... 为实现高铁锌焙砂中锌的选择性浸出,提出一种将还原焙烧与磁化焙烧相结合以强化铁酸锌选择性分解的新工艺。通过热力学分析和焙烧实验,详细研究铁酸锌的分解机理。结果表明,在8%CO(体积分数)、750℃、50%CO/(CO+CO_(2))(体积分数)和90 min的最佳还原焙烧条件下,锌焙砂中94.65%的铁酸锌被还原分解为氧化锌和氧化亚铁。随后,还原焙砂在450℃的空气气氛中磁化焙烧30 min后,焙砂中的氧化亚铁被选择性地磁化为四氧化三铁。磁化焙砂经低酸浸出后,焙砂中93.62%的锌被浸出进入溶液,而90%以上的铁以磁铁矿的形式富集在浸出渣中,浸出渣中的铁可通过磁选法进一步回收。 展开更多
关键词 铁酸锌 锌焙砂 还原焙烧 磁化焙烧 酸性浸出
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