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肾内科教学中采用SHARP反馈法的效果及对教学满意度的影响
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作者 叶寅寅 杨沿浪 《中国医药科学》 2024年第4期63-66,共4页
目的探析SHARP反馈法在肾内科教学中的应用效果。方法选取2021年5月至2022年5月皖南医学院弋矶山医院肾内科实习生50名,依据随机数表法分为两组,每组各25名。对照组采用传统教学方法,观察组采用SHARP反馈法。比较两组学习成绩、教学质... 目的探析SHARP反馈法在肾内科教学中的应用效果。方法选取2021年5月至2022年5月皖南医学院弋矶山医院肾内科实习生50名,依据随机数表法分为两组,每组各25名。对照组采用传统教学方法,观察组采用SHARP反馈法。比较两组学习成绩、教学质量评分及教学满意度。结果观察组学生学习成绩、教学质量评分包括学习和学术价值、教师的情操、组织和表达、师生关系和互动、教师知识面评分高于对照组,差异有统计学意义(P<0.05),观察组教学满意度、学习能力评分包括学生临床思维、课堂氛围、自学能力、临床实践能力、表达能力及知识关联能力高于对照组,差异有统计学意义(P<0.05)。结论肾内科教学中采用SHARP反馈法教学的效果明显,可提升实习生学习成绩,为实习生提供高质量教学,同时提升实习生对教学方法的满意度,临床教学中可大力推广及应用。 展开更多
关键词 肾内科 sharp反馈法 教学满意度 考核成绩
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向量值多线性奇异积分算子的加权Sharp不等式
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作者 赵巧珍 黄得建 《海南热带海洋学院学报》 2024年第2期96-103,共8页
利用不等式、原子分解性质研究了向量值多线性算子,证明了某些向量值多线性奇异积分算子的一个加权Sharp不等式,并利用此不等式得到了该向量值多线性算子的加权Lp型不等式和L log L型不等式。
关键词 向量值多线性算子 奇异积分算子 sharp不等式 BMO Ap-加权
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Management of Penetrating Cranioencephalic Trauma Caused by Sharp Metal Objects—Therapeutic and Evolutionary Aspects: 12 Cases at the Renaissance University Hospital in N’Djamena
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作者 Goumantar Félicien Toudjingar Li-Iyane Olivier Ouambi +3 位作者 Yannick Canton Kessely Donal Djasdé Mahouli Fata Vounki Momar Codé Ba 《Open Journal of Modern Neurosurgery》 2024年第2期170-178,共9页
Introduction: Cranioencephalic trauma caused by bladed weapons is rare, and that caused by sharp objects is exceptional. The aim of our study was to describe the clinical, therapeutic and evolutionary aspects. Materia... Introduction: Cranioencephalic trauma caused by bladed weapons is rare, and that caused by sharp objects is exceptional. The aim of our study was to describe the clinical, therapeutic and evolutionary aspects. Materials and method: This was a descriptive and analytical study over a 48-month period at CHU la Renaissance from January 1, 2018 to December 31, 2021, concerning patients admitted for penetrating cranioencephalic trauma by pointed object. Results: Twelve cases, all male, of penetrating cranioencephalic sharp-force trauma were identified. The mean age was 34 ± 7 years, with extremes of 11 and 60 years. Farmers and herders accounted for 31% and 25% of cases respectively. The average admission time was 47 hours. Brawls were the circumstances of occurrence in 81.2% of cases. Knives (33%), arrows (25%) and iron bars (16.6%) were the objects used. Altered consciousness was present in 43.8% of cases, and focal deficit in 50%. Scannographic lesions were fracture and/or embarrhment (12 cases), intra-parenchymal haematomas (6 cases) and presence of object in place (4 cases). Surgery was performed in 11 patients. Postoperative outcome was favorable in 9 patients. After 12 months, 2 patients were declared unfit. Conclusion: Penetrating head injuries caused by sharp objects are common in Chad. Urgent surgery can prevent disabling after-effects. 展开更多
关键词 Penetrating Trauma SKULL Encephalon sharp Object Surgery Patient Outcome
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Application Analysis of Nursing Students'Grades in Course Relevance Based on Association Rule Mining Algorithm Apriori
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作者 Xuemei Li Edward CJimenez 《Journal of Contemporary Educational Research》 2024年第2期213-223,共11页
By analyzing the correlation between courses in students’grades,we can provide a decision-making basis for the revision of courses and syllabi,rationally optimize courses,and further improve teaching effects.With the... By analyzing the correlation between courses in students’grades,we can provide a decision-making basis for the revision of courses and syllabi,rationally optimize courses,and further improve teaching effects.With the help of IBM SPSS Modeler data mining software,this paper uses Apriori algorithm for association rule mining to conduct an in-depth analysis of the grades of nursing students in Shandong College of Traditional Chinese Medicine,and to explore the correlation between professional basic courses and professional core courses.Lastly,according to the detailed analysis of the mining results,valuable curriculum information will be found from the actual teaching data. 展开更多
关键词 Grade analysis Apriori algorithm Course relevance Data mining
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Characterization and comparison of the aroma-active compounds on different grades of sesame-flavor Baijiu by headspace solid-phase microextraction and gas chromatography-olfactometry-mass spectrometry 被引量:4
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作者 Dan Qin Jiawen Duan +4 位作者 Hehe Li Fuping Zheng Huan Cheng Xingqian Ye Baoguo Sun 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期79-88,共10页
This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfact... This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfactometry-mass spectrometry(GC-O-MS).A total of 54 aroma-active compounds were detected.Principal component analysis showed that JZ1,JZ2,and JZ3 were well separated from each other.JZ1 as the premium-grade Baijiu had the highest aroma intensities,concentrations.According to aroma intensities and concentrations,dimethyl trisulfide,butanoic acid,phenylacetaldehyde,2-furylmethanethiol,ethyl hexanoate,2,6-dimethylpyrazine,etc.could be potentially applied as volatile makers to distinguish the three different grades of sesame-flavor Baijiu as their significant difference(P<0.05)in three Baijiu samples.Roasted aroma had the significant difference(P<0.05)in three sample base on aroma profiles.Meanwhile,2-furylmethanethiol,2,6-dimethylpyrazine were related to the roasted aroma,they may be had a significant contribution to the differences of three different grades of sesame-flavor Baijiu.This study has provided a comprehensive understanding of the differences of three different grades of sesame-flavor Baijiu. 展开更多
关键词 Sesame-flavor Baijiu Baijiu grades Sensory evaluation Principal component analysis 2-Furylmethanethiol
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Corrigendum to“Introgression of sharp eyespot resistance from Dasypyrum villosum chromosome 2VL into bread wheat”[Crop J.11(2023)1512–1520]
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作者 Caiyun Liu Wei Guo +9 位作者 Yang Wang Bisheng Fu Jaroslav Dolezel Ying Liu Wenling Zhai Mahmoud Said István Molnár Katerina Holušová Ruiqi Zhang Jizhong Wu 《The Crop Journal》 SCIE CSCD 2023年第6期1949-1949,共1页
The authors regret to report some missing information in the authorship and associated changes of the paper.On page 1512,the author information reads:“Caiyun Liu a,Wei Guo a,Yang Wang b,Bisheng Fu a,Jaroslav Dolezel ... The authors regret to report some missing information in the authorship and associated changes of the paper.On page 1512,the author information reads:“Caiyun Liu a,Wei Guo a,Yang Wang b,Bisheng Fu a,Jaroslav Dolezel c,Ying Liu a,Wenling Zhai a,Mahmoud Said c,d,István Molnár c,d,e,Katerina Holušovác,Ruiqi Zhang b,*,Jizhong Wu a,f,g,*”.It should be changed to“Caiyun Liu a,1,Wei Guo a,1,Yang Wang b,Bisheng Fu a,Jaroslav Dolezel c,Ying Liu a,Wenling Zhai a,Mahmoud Said c,d,István Molnár c,d,e,Katerina Holušovác,Ruiqi Zhang b,*,Jizhong Wu a,f,g,*”.On page 1512 in the footnote,the following sentence should be added below the corresponding authors’information:1 These authors contributed equally to this work.The correction has been updated above.The authors would like to apologize for any inconvenience caused. 展开更多
关键词 sharp correction BREAD
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Hydrodynamic Behavior of Gap Resonance in Multiple-Box Systems with Sharp and Round Inlet Configurations
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作者 RAN Ya-qing JIANG Sheng-chao +1 位作者 GENG Bao-lei JIN Rui-jia 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期849-862,共14页
Fluid resonance within narrow gaps in multiple-box systems with sharp and round inlet configurations are investigated by using the potential flow and viscous fluid flow models in the OpenFOAM^(■)package.Evident discr... Fluid resonance within narrow gaps in multiple-box systems with sharp and round inlet configurations are investigated by using the potential flow and viscous fluid flow models in the OpenFOAM^(■)package.Evident discrepancy between two numerical models can be observed for sharp inlet configurations.In addition to the dramatical decrease of resonant amplitude in narrow gaps,some peak values at the higher resonant frequencies predicted by the potential flow model even disappear in the viscous fluid flow results.The decreased normalized resonant amplitudes with the increase of incident wave amplitude can be observed for sharp inlet configurations.However,the hydrodynamic behaviors of multiple-box system with round inlet configurations between potential flow and viscous fluid flow models are quite similar with each other.The normalized resonant amplitudes are nearly independent of incident wave amplitudes for multiple-box systems with round inlet configurations.This implies that the energy dissipation associated with fluid viscosity and flow rotation plays an important role in the gap resonance for sharp inlet configurations;while it is insignificant for round inlet configurations. 展开更多
关键词 fluid resonance multiple boxes sharp edge round edge OpenFOAM
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Effect of sharp vacuum-plasma boundary on the electron injection and acceleration in a few-cycle laser driven wakefield
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作者 张国博 刘松 +5 位作者 邹德滨 崔野 刘建鹏 杨晓虎 马燕云 邵福球 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期342-347,共6页
The electron injection and acceleration driven by a few-cycle laser with a sharp vacuum-plasma boundary have been investigated through three-dimensional(3D)particle-in-cell simulations.It is found that an isotropic bo... The electron injection and acceleration driven by a few-cycle laser with a sharp vacuum-plasma boundary have been investigated through three-dimensional(3D)particle-in-cell simulations.It is found that an isotropic boundary impact injection(BII)first occurs at the vacuum-plasma boundary,and then carrier-envelope-phase(CEP)shift causes the transverse oscillation of the plasma bubble,resulting in a periodic electron self-injection(SI)in the laser polarization direction.It shows that the electron charge of the BII only accounts for a small part of the total charge,and the CEP can effectively tune the quality of the injected electron beam.The dependences of laser intensity and electron density on the total charge and the ratio of BII charge to the total charge are studied.The results are beneficial to electron acceleration and its applications,such as betatron radiation source. 展开更多
关键词 laser wakefield acceleration few-cycle laser sharp vacuum-plasma boundary
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Genome sequencing reveals the evolution and pathogenic mechanisms of the wheat sharp eyespot pathogen Rhizoctonia cerealis
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作者 Lin Lu Feilong Guo +5 位作者 Zhichao Zhang Xiuliang Zhu Yu Hao Jinfeng Yu Wenwu Ye Zengyan Zhang 《The Crop Journal》 SCIE CSCD 2023年第2期405-416,共12页
The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent stra... The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies. 展开更多
关键词 EFFECTOR EVOLUTION Pathogenesis Rhizoctonia cerealis Secretory proteins sharp eyespot Wheat(Triticum aestivum)
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Spatial and Temporal Distribution of Different Grades of Short-time Precipitation in Xining City
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作者 Liang XU Yongling SU 《Meteorological and Environmental Research》 CAS 2023年第1期21-23,共3页
Based on the hourly precipitation data from 4 observation stations of Xining City from June to September during 2005-2011,the temporal and spatial distribution characteristics of short-time precipitation were analyzed... Based on the hourly precipitation data from 4 observation stations of Xining City from June to September during 2005-2011,the temporal and spatial distribution characteristics of short-time precipitation were analyzed.The results show that the precipitation distribution in Xining region exhibited the less-more-less trend from southwest to northeast,while the torrential rain gradually increased from the northwest and southwest to the middle.The hourly general precipitation in Xining region had obviously seasonal characteristics,and its annual distribution showed wavy changes,but the annual variation of short-time heavy precipitation and rainstorm was very obvious.Furthermore,short-time heavy precipitation was concentrated from 18:00 to 24:00,followed by 03:00-07:00 on the following day.The occurrence time of short-time rainstorm accorded with short-time heavy precipitation.It offers a useful reference for the accurate and timely short-term forecast. 展开更多
关键词 DIFFERENT grades Short-time PRECIPITATION Temporal-spatial DISTRIBUTION
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Influence of Online Learning Attitude in the Blended Teaching Model on the Final Grades
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作者 YUE Wen-ting WANG Jin-jun ZHAO Yu 《Journal of Literature and Art Studies》 2023年第5期383-388,共6页
The combination of online teaching and traditional offline teaching can maximize the advantages of both.Based on the blended teaching of English Reading course,39 students were selected as the research subjects to stu... The combination of online teaching and traditional offline teaching can maximize the advantages of both.Based on the blended teaching of English Reading course,39 students were selected as the research subjects to study the relationship between their online learning attitudes and their grades in the final examination.Judged from the number of times for each student to download teaching resources,the number of assignments submitted online,and the quality of the submitted assignments,each student’s attitude toward online learning was examined comprehensively,and a correlation analysis was conducted through SPSS Statistics 21.0 to explore the influence of online learning attitude on English reading performance.Through data collection and analysis of the online learning attitudes over a 16-week period,a significant positive correlation was found between the online learning attitudes and the English reading grades,indicating that the online learning attitude in the blended learning model plays a crucial role in improving the English reading skill,and students should maintain a positive attitude toward online teaching in blended learning. 展开更多
关键词 blended teaching model online learning attitude correlation analysis final grade of English Reading
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热敏灸治疗颈型颈椎病的Meta分析及GRADE证据等级评价
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作者 周佳佳 邓秀红 +1 位作者 易媛媛 雷丽芳 《中国中医药现代远程教育》 2024年第7期107-110,共4页
目的系统评价热敏灸及其综合疗法用于颈型颈椎病的临床效果,为热敏灸治疗颈型颈椎病提供更好的证据来源。方法收集国内外各大数据库热敏灸及其综合疗法用于颈型颈椎病的随机对照试验(RCT),通过Revman 5.3软件进行Meta分析,按照GRADE标... 目的系统评价热敏灸及其综合疗法用于颈型颈椎病的临床效果,为热敏灸治疗颈型颈椎病提供更好的证据来源。方法收集国内外各大数据库热敏灸及其综合疗法用于颈型颈椎病的随机对照试验(RCT),通过Revman 5.3软件进行Meta分析,按照GRADE标准对结局指标进行证据质量评价。结果纳入9篇文献共855例患者,Meta分析结果提示:热敏灸及其综合疗法组在提高总有效率(RR=1.19,P<0.01)和治愈率(RR=1.73,P<0.01)、降低视觉模拟量表(VAS)评分(SMD=-0.73,P<0.01)、简化McGill疼痛问卷(SF-MPQ)评分(SMD=-1.28,P<0.05)以及NPQ颈痛量表评分(SMD=-0.81,P<0.05)方面都优于对照组;GRADE证据等级评价提示:前三者为低质量证据,后二者为极低质量证据。结论热敏灸及其综合疗法用于颈型颈椎病在提高临床效果、镇痛以及改善患者生活质量方面更具优势。 展开更多
关键词 颈型颈椎病 热敏灸 META分析 GRADE评价
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A Preliminary Study on Strategies to Improve Writing Skills in Lower Grades of Primary School
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作者 Xiying Ji 《Journal of Contemporary Educational Research》 2023年第12期29-34,共6页
Teaching writing is an essential component of Chinese education in primary schools and an important foundation for students’reading,writing,and core literacy development.However,due to various reasons,children in the... Teaching writing is an essential component of Chinese education in primary schools and an important foundation for students’reading,writing,and core literacy development.However,due to various reasons,children in the lower grades always face multiple difficulties in the learning task of writing.Based on this educational status quo,this article puts forward strategic suggestions for improving writing skills in the lower grades of primary school.Teachers should analyze students and attend to each student individually,optimize teaching methods,and implement hierarchical teaching.They should also strengthen the training of students’fine motor skills to solidify the physiological foundation for writing.Emphasis should be placed on cultivating the core quality of aesthetic creation.Employing multiple process evaluations can inspire children’s long-term interest in learning. 展开更多
关键词 Lower grades of primary school Writing strategies Fine motor Aesthetic creation Process evaluation
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乌梅丸及加减方治疗大肠疾病的系统评价再评价
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作者 张洁 杨清瑞 +4 位作者 雷玉玉 陈欢 李彩玲 李翠 杜晓泉 《天津中医药》 CAS 2024年第2期191-198,共8页
[目的]评价乌梅丸及加减方治疗大肠疾病的相关系统评价(SRs),为临床提供循证医学依据。[方法]计算机检索PubMed、Cochrane Library、Embase、中国期刊全文数据库(CNKI)、维普中文期刊数据库(VIP)、万方数据知识服务平台(WanFang Data)... [目的]评价乌梅丸及加减方治疗大肠疾病的相关系统评价(SRs),为临床提供循证医学依据。[方法]计算机检索PubMed、Cochrane Library、Embase、中国期刊全文数据库(CNKI)、维普中文期刊数据库(VIP)、万方数据知识服务平台(WanFang Data)和中国生物医学文献数据库(CBM),搜集乌梅丸及加减方治疗大肠疾病的SRs,检索时限为建库至2022年12月31日。两名研究者独立筛选文献、提取资料,分别采用AMSTAR 2、PRISMA 2020和GRADE评价纳入研究的方法学质量、报告质量及证据质量,并对结果进行综合分析。[结果]共纳入12篇SRs,涉及4种疾病,有溃疡性结肠炎(UC)、肠易激综合征(IBS)、泄泻和大肠腺瘤性息肉术后。AMSTAR 2评价结果显示,10篇SRs为低质量,2篇SRs为极低质量;PRISMA 2020评分为19.5~30分,其中6篇SRs为中质量,6篇SRs为低质量。纳入SRs共报告了51个结局指标,GRADE评价结果为30个中质量,19个低质量,2个极低质量。现有证据显示,与常规治疗、空白对照/安慰剂相比,乌梅丸及加减方或联合常规治疗治疗UC、IBS、泄泻和大肠腺瘤性息肉术后的疗效更佳。[结论]乌梅丸及加减方治疗大肠疾病具有较好的疗效,鉴于所纳入研究的样本量及疾病种类较少,其方法学质量、报告质量和证据质量相对较低,应慎重对待该结论,期待今后开展更多高质量研究证实。 展开更多
关键词 乌梅丸 大肠疾病 系统评价再评价 AMSTAR 2 PRISMA 2020 GRADE
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新旧世界葡萄酒质量表达演变及形成
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作者 杨和财 房玉林 安鲁 《西北农林科技大学学报(社会科学版)》 北大核心 2024年第1期152-160,共9页
葡萄酒等级是全球葡萄酒行业的关注点。在旧世界葡萄酒等级表达中,产品等级不仅反映产品内在质量,还与具有质量风格的地理特征紧密相关;新世界葡萄酒等级表达中,葡萄酒地理特征仅表示产品来源真实性,葡萄酒质量以产品口感为基础并满足... 葡萄酒等级是全球葡萄酒行业的关注点。在旧世界葡萄酒等级表达中,产品等级不仅反映产品内在质量,还与具有质量风格的地理特征紧密相关;新世界葡萄酒等级表达中,葡萄酒地理特征仅表示产品来源真实性,葡萄酒质量以产品口感为基础并满足消费者消费偏好需求。葡萄酒官方等级分级具有从产区到列级酒庄的纵向化结构,葡萄酒等级分类具有从品种、年份到酒庄的横向化结构,前者分级以生产者视角下“为何分级”并同时聚焦分级内生形成关键要素,后者分类以消费者视角下“为何分类”并锚定产品质量的某一关键要素,两者之间关注点存在差异。这种差异给国际葡萄酒市场创造竞争空间,形成一种质量表达的实践共创、智慧共存的竞争格局。 展开更多
关键词 葡萄酒 质量表达 葡萄酒等级 等级分类
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“禹城式”矽卡岩型富铁矿的形成机制 被引量:1
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作者 张招崇 王怀洪 +4 位作者 谢秋红 沈立军 朱裕振 吕云鹤 金博文 《现代地质》 CAS CSCD 北大核心 2024年第1期1-12,共12页
山东省西北部齐河—禹城地区矽卡岩型富铁矿找矿工作取得了重大突破,有望成为继莱芜、金岭和济南之后又一个重要的富铁矿基地。与传统的矽卡岩型铁矿产于岩体与碳酸盐岩接触带不同的是,齐河—禹城地区李屯铁矿的矿体产于石炭系—二叠系... 山东省西北部齐河—禹城地区矽卡岩型富铁矿找矿工作取得了重大突破,有望成为继莱芜、金岭和济南之后又一个重要的富铁矿基地。与传统的矽卡岩型铁矿产于岩体与碳酸盐岩接触带不同的是,齐河—禹城地区李屯铁矿的矿体产于石炭系—二叠系含煤地层内,富铁矿体与围岩呈截然的接触关系,并且矿体附近的围岩发生了强烈的角岩化。针对这一现象,本文提出上覆的煤系极低的热导率使得含矿热液能够保持高温状态,发生长距离迁移而就位于远接触带的石炭系—二叠系中。李屯铁矿的形成可能是高温的岩浆流体与低温的大气降水混合,导致温度和盐度下降发生快速沉淀的结果。另外,近矿岩体普遍发生强烈的钠长石化,导致了闪长质岩石“铁的丢失”,为出溶高浓度富铁流体以及富铁矿的形成奠定了重要的物质基础。幔源“高分异”的闪长岩以及浅侵位时岩浆流体的出溶,也是邯邢式铁矿形成的先决条件。 展开更多
关键词 矽卡岩 富铁矿 流体迁移 钠长石化 禹城式
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西藏南部极低级变质岩及其地质与资源意义
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作者 毕先梅 莫宣学 刘艳宾 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期201-210,共10页
极低级变质作用(very low-grade metamorphism)是当代地球科学的前沿研究课题之一。极低级变质岩(very low-grade metamorphic rocks)既是地质过程的记录,又在资源环境方面有实用意义。西藏南部广泛分布着处于成岩-极低级变质-低级变质... 极低级变质作用(very low-grade metamorphism)是当代地球科学的前沿研究课题之一。极低级变质岩(very low-grade metamorphic rocks)既是地质过程的记录,又在资源环境方面有实用意义。西藏南部广泛分布着处于成岩-极低级变质-低级变质阶段的岩石。它们记录了从新特提斯到青藏高原形成发展的诸多信息,并为在西藏南部寻找油气资源提供了有用的线索。本文对采自西藏南部不同地点和构造单元的71件珍贵的富含黏土矿物的岩石样品进行了XRD分析,获得了71套以伊利石结晶度(Ic)为主的黏土矿物数据。数据表明,这些岩石的伊利石结晶度(Ic)在0.21°~1.61°(Δ2θ)范围内,分别落在低级成岩区、高级成岩区、极低级变质区、低级变质区。不同构造单元显示不同的变质特点。北喜马拉雅碳酸盐台地P_(2),J-K,K_(2)均属极低级变质,N显示早期成岩阶段特征。拉轨岗日被动陆缘盆地发育P1,T_(1),T_(2),T_(3),J_(1),J-K,K_(1),K_(2)地层,绝大多数均遭受极低级变质,总的趋势是随着时代变新变质程度逐渐降低,具有埋藏变质的特点。也有部分样品的Ic落在成岩带内,提供了寻找油气的线索。从雅鲁藏布蛇绿(混杂)岩带中的沉积岩样品获得两组数据:一组相当于成岩阶段;另一组相当于极低级变质。初步解释,前者可能反映蛇绿岩形成时的古环境条件,后者可能代表蛇绿岩碰撞定位阶段的记录。日喀则弧前盆地中K_(2)(日喀则群)虽然有较强的褶皱变形,但变质程度不高,属高级成岩带,可能说明晚白垩世弧前盆地沉积并未卷入俯冲作用。冈底斯岩浆弧中侵入岩、火山岩、沉积岩均发育,沉积岩的伊利石结晶度(Ic),落入低级变质-极低级变质-成岩作用带的较宽范围,并显示埋藏变质与岩浆作用叠加的特点。西藏南部成岩阶段沉积岩-极低级变质岩中还蕴藏着有关石油天然气的信息。特别是,白垩纪中期发生的全球性的缺氧事件,也影响了西藏南部地区,已经在岗巴-定日盆地发现典型的黑色页岩,厚度巨大。前人研究还认为,定日-岗巴被动大陆边缘、羌塘周缘前陆盆地、冈底斯弧背盆地具有良好含油气前景。本文对西藏南部极低级变质作用和极低级变质岩做了初步研究,期望今后有更深入的研究。 展开更多
关键词 极低级变质作用 极低级变质岩 西藏南部 伊利石结晶度(Ic) 地质与资源意义
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应力驱动的2.5D梯度各向异性维诺多孔零件轻量化建模方法
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作者 曹伟 潘文珺 +2 位作者 刘斌 路平 江开勇 《计算机集成制造系统》 EI CSCD 北大核心 2024年第3期1036-1049,共14页
为了提高多孔零件的设计自由度、内部力学性能梯度与实际应力分布的匹配度,提出一种应力驱动的2.5D梯度各向异性维诺多孔零件轻量化设计方法。将零件有限元分析结果分解为应力标量场和应力方向场,通过加权随机采样算法将应力标量场映射... 为了提高多孔零件的设计自由度、内部力学性能梯度与实际应力分布的匹配度,提出一种应力驱动的2.5D梯度各向异性维诺多孔零件轻量化设计方法。将零件有限元分析结果分解为应力标量场和应力方向场,通过加权随机采样算法将应力标量场映射为零件设计域内的维诺站点分布,实现零件内部力学性能的梯度分布;将应力方向场映射为二维黎曼流形,提出一种基于胞元择优方向生长策略的各向异性维诺图生成算法,生成胞元沿黎曼流形分布的各向异性维诺图。在此基础上,通过偏置算法、调和距离场和拉伸算法生成光滑的梯度各向异性维诺多孔零件。最后,采用有限元分析、三点弯曲实验等方法将所设计的多孔零件和其他多孔零件进行比较分析。实验结果表明,所提出的梯度各向异性维诺多孔零件建模方法能有效提升零件内部力学性能梯度与实际应力分布的匹配度,降低材料消耗,实现轻量化设计。 展开更多
关键词 轻量化设计 多孔结构 各向异性 梯度 维诺图
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IDH突变和1p/19q共缺失型少突胶质细胞瘤临床病理特征和预后分析
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作者 吴小延 王苏杰 +2 位作者 王芳 杜紫明 邓玲 《肿瘤防治研究》 CAS 2024年第3期178-184,共7页
目的探讨I D H突变和1p/19q共缺失型少突胶质细胞瘤的临床病理特征及预后相关影响因素。方法收集54例IDH突变和1p/19q共缺失型少突胶质细胞瘤病例,分析其临床病理特点,包括年龄、组织学分级和肿瘤部位等因素对无进展生存期和总生存期的... 目的探讨I D H突变和1p/19q共缺失型少突胶质细胞瘤的临床病理特征及预后相关影响因素。方法收集54例IDH突变和1p/19q共缺失型少突胶质细胞瘤病例,分析其临床病理特点,包括年龄、组织学分级和肿瘤部位等因素对无进展生存期和总生存期的影响。结果 54例患者中,肿瘤发生于1个脑叶者46例,发生于2个脑叶以上者8例。肿瘤组织学WHO分级2级12例,3级42例。FISH检测显示54例均为1p/19q共缺失;免疫组织化学检测显示Olig2均为弥漫强阳性;GFAP均为阳性;p53有6例强阳性;48例患者ATRX未缺失;Ki-67增殖指数5%~60%。Sanger测序显示54例均发生IDH基因突变(40例为IDH1突变,14例为IDH2突变),33例发生TERT启动子突变。16例在治疗过程中发生复发及转移。单因素分析显示,手术后复发转移间隔时间超过2年可以延长患者无进展生存和总生存期。54例患者平均无进展生存期33.5个月,平均总生存期40.7个月。结论 IDH突变和1p/19q共缺失型少突胶质细胞瘤术后联合精准放化疗降低了进展风险,手术后复发转移间隔时间与该型患者预后相关。 展开更多
关键词 少突胶质细胞瘤 病理特征 组织学分级 基因检测 预后
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核转录因子红系2相关因子2和p62在宫颈鳞状细胞癌和上皮内病变中的表达及诊断价值
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作者 郑桂华 金晓霞 +3 位作者 陶玉梅 刘丹阳 朱兴华 卫颖泽 《安徽医药》 CAS 2024年第3期491-495,I0005,共6页
目的 探讨核转录因子红系2相关因子2(Nrf2)与选择性自噬接头蛋白p62/Sequestosome1 (SQSTM1)在诊断宫颈癌和上皮内病变中的价值,并且分析二者在不同宫颈病变中的相关性。方法 收集2008年1月至2021年12月南通市肿瘤医院120例宫颈鳞状细胞... 目的 探讨核转录因子红系2相关因子2(Nrf2)与选择性自噬接头蛋白p62/Sequestosome1 (SQSTM1)在诊断宫颈癌和上皮内病变中的价值,并且分析二者在不同宫颈病变中的相关性。方法 收集2008年1月至2021年12月南通市肿瘤医院120例宫颈鳞状细胞癌(SCC)、102例低级别鳞状上皮内病变(LSIL)和101例高级别鳞状上皮内病变(HSIL)病人及49例宫颈良性/反应性鳞状上皮病人的石蜡标本,免疫组织化学方法检测其中Nrf2和p62的表达,并分析二者在不同宫颈病变中的相关性及评估二者在诊断中的价值。结果 Nrf2和p62在LSIL、HSIL和SCC中表达明显高于良性/反应性宫颈鳞状上皮(均P<0.05),Nrf2和p62在HSIL和SCC中表达明显高于LSIL(均P<0.05),p62在SCC中表达明显高于HSIL(P<0.05),而Nrf2在HSIL中表达稍低于SCC(P<0.05)。Nrf2和p62在良性/反应性宫颈鳞状上皮、LSIL、HSIL和SCC中均具有正相关性,相关系数分别为0.63、0.58、0.69和0.38(均P<0.05)。ROC曲线结果显示,除Nrf2在诊断HSIL与SCC中差异无统计学意义外,Nrf2、p62以及联合Nrf2和p62在诊断良性/反应性鳞状上皮与LSIL、良性/反应性鳞状上皮与HSIL、良性/反应性鳞状上皮与SCC、LSIL与HSIL、LSIL与SCC、HSIL与SCC各个组别中均差异有统计学意义(均P<0.05)。结论 Nrf2和p62在良性/反应性鳞状上皮中不表达或低表达,LSIL中表达有所增高,HSIL和SCC中表达最高,二者在不同宫颈病变中均具有正相关性,而且单独使用Nrf2或p62就能够有效诊断不同的宫颈病变,二者联用诊断效果更佳。 展开更多
关键词 宫颈疾病 核转录因子红系2相关因子2 选择性自噬接头蛋白 良性/反应性 低级别 高级别 鳞状上皮内病变 鳞状细胞癌
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