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Migration patterns and spatial connectivity of Pallas's Gulls (Ichthyaetus ichthyaetus) from Alakol lake, Kazakhstan using ring recovery and tracking data
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作者 Viktoriya O.Ilina Bekzhan T.Berdikulov +5 位作者 Fumin Lei Aleksandr N.Filimonov Yekaterina E.Akentyeva Gang Song Aizhan E.Tashimova Andrey E.Gavrilov 《Avian Research》 2025年第3期457-466,共10页
Understanding migration patterns and spatial connectivity is crucial for conserving long-distance migratory birds. While satellite telemetry has advanced the study of large gulls, Pallas's Gull (Ichthyaetus ichthy... Understanding migration patterns and spatial connectivity is crucial for conserving long-distance migratory birds. While satellite telemetry has advanced the study of large gulls, Pallas's Gull (Ichthyaetus ichthyaetus) remains relatively understudied, with limited data on its migration routes and habitat use, particularly in Central Asia. This study integrates 684 ring recoveries (1968–2024) and GPS tracking data to analyze the migration ecology of individuals breeding at Alakol Lake, Kazakhstan. Ring recoveries confirm migratory connectivity across Kazakhstan, Russia, Uzbekistan, Turkmenistan, Iran, and Pakistan, with wintering records as far as India, Kuwait, Bangladesh, and Ethiopia. GPS tracking of a single individual (June 2020–August 2021) revealed a migration route from Alakol Lake to the Arabian Sea, with key stopovers at Zaisan Lake, Balkhash Lake, the Aral Sea, Aydar Lake, and the Amu Darya River. Notably, a post-breeding northward dispersal to Zaisan Lake and southern Russia was identified before the southward migration commenced. These findings highlight the significance of Kazakhstan's lakes as breeding and migratory hubs and the need to protect critical stopover sites in Central Asia. Given increasing anthropogenic pressures on wetland habitats, this research provides essential baseline data for conservation planning and enhances the broader understanding of gull migration ecology. 展开更多
关键词 lalcol lalke GPS trackingi Gulls Pallas's Gull Ringing birds ing recoveryi Waterbird migration
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Modeling and performance analysis of real⁃time BDS⁃3 PPP⁃B2b one⁃way timing with uncombined observations
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作者 WANG Yong LIU Tianjun +2 位作者 GU Shengfeng GE Yulong JIANG Weiping 《Journal of Southeast University(English Edition)》 2025年第1期67-77,共11页
Currently,the BeiDou⁃3(BDS⁃3)precise point positioning(PPP)service(PPP⁃B2b)mostly employs the ionosphere⁃free(IF)combination model for precise timing,which tends to amplify the noise in observation values.To address t... Currently,the BeiDou⁃3(BDS⁃3)precise point positioning(PPP)service(PPP⁃B2b)mostly employs the ionosphere⁃free(IF)combination model for precise timing,which tends to amplify the noise in observation values.To address this issue,this paper proposes a real⁃time BDS⁃3 precise unidirectional timing model based on uncombined(UC)observations using the BDS⁃3 PPP⁃B2b service.This model resolves the challenge of the amplified observation noise inherent in the IF combination model.The experiment involved selecting eight global navigation satellite system(GNSS)observation stations within China and collecting continuous observation data for 15 d.A comparative analy⁃sis with the traditional dual⁃frequency IF combination PPP timing model showed that the BDS⁃3 UC PPP timing based on the BDS⁃3 PPP⁃B2b service can achieve a timing preci⁃sion of 0.5 ns.In addition,it was found that due to global positioning system(GPS)satellite clock products in the BDS⁃3 PPP⁃B2b service not being unified to the standard time,the GPS IF PPP timing method based on the BDS⁃3 PPP⁃B2b service is not recommended for precise timing.In summary,the BDS⁃3 UC PPP timing model proposed in this paper is suitable for precise timing,providing observa⁃tion values with smaller noise,and its timing accuracy is comparable to that of the BDS⁃3 IF PPP,with slightly better frequency stability. 展开更多
关键词 precise point positioning service precise tim⁃ing BDS⁃3 uncombined precise point positioning
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运用Morphing变换提取地性线算法研究 被引量:1
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作者 赵彬彬 谢建湘 +2 位作者 张宏奎 王笠苇 王倩 《武汉大学学报(信息科学版)》 北大核心 2025年第1期174-183,共10页
由等高线获取山谷(脊)线对地形分析、坡度坡向计算和库区设计等应用具有重要的现实意义和非常高的生产价值。当前,面向等高线的地性线提取大多采用特征点连接法,其提取的地性线易与等高线发生空间逻辑冲突,在等高线弯曲形状较多变、较... 由等高线获取山谷(脊)线对地形分析、坡度坡向计算和库区设计等应用具有重要的现实意义和非常高的生产价值。当前,面向等高线的地性线提取大多采用特征点连接法,其提取的地性线易与等高线发生空间逻辑冲突,在等高线弯曲形状较多变、较复杂的区域,所获取的山谷(脊)线存在与等高线弯曲特征不符且偏离较严重等问题。因此,依据地理学第一定律分析了等高线整体形态及局部形状特征,基于Morphing变换技术,提出了一种兼顾地性线两侧等高线形状特征,同时顾及山谷(脊)特征点位置约束的地性线提取新方法。首先,凭借各等高线的高程及其层次关系构建等高线树,并根据等高线上节点凹凸属性进行等高线弯曲分割,以高效准确地提取地形特征点;然后,以地形特征点为界构建其两侧等高线各节点之间的极优映射关系;最后,以地形特征点为约束,采用基于渐变移位距离值的Morphing变换提取地性线。实验结果表明,该方法能准确地提取出完整的与实际地形相吻合亦兼顾等高线整体形态与走势的地性线。 展开更多
关键词 地理学第一定律 等高线树 地形特征点 地性线 Morphing变换
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谈谈动词后加-ing的规则
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作者 罗杏焕 《语言教育》 1996年第11期73-74,共2页
1.英语动词加-ing,通常是在原形词尾直接加-ing 构成:cough—cough-ing,climb—climbing,stand—standing,fight—fighting2.以-e 结尾的动词a)如果动词原形以—辅音加—不发音的-e 结尾,一般应去掉 e 再加-ing:write—writing,hope—ho... 1.英语动词加-ing,通常是在原形词尾直接加-ing 构成:cough—cough-ing,climb—climbing,stand—standing,fight—fighting2.以-e 结尾的动词a)如果动词原形以—辅音加—不发音的-e 结尾,一般应去掉 e 再加-ing:write—writing,hope—hoping,care—caring,stare—staring,plane—plan-ing,have—having,save—saving,produce——producing,breathe—breathing但 singe 一词例外。 展开更多
关键词 ing FIGHTing COUGH producing stand write writing BREATHing SAVing 重读音节
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Comprehensive analysis of clinical and biological value of ING family genes in liver cancer
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作者 Shi-Cai Liu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2592-2609,共18页
BACKGROUND Liver cancer(LIHC)is a malignant tumor that occurs in the liver and has a high mortality in cancer.The ING family genes were identified as tumor suppressor genes.Dysregulated expression of these genes can l... BACKGROUND Liver cancer(LIHC)is a malignant tumor that occurs in the liver and has a high mortality in cancer.The ING family genes were identified as tumor suppressor genes.Dysregulated expression of these genes can lead to cell cycle arrest,senescence and/or apoptosis.ING family genes are promising targets for anticancer therapy.However,their role in LIHC is still not well understood.AIM To have a better understanding of the important roles of ING family members in LIHC.METHODS A series of bioinformatics approaches(including gene expression analysis,genetic alteration analysis,survival analysis,immune infiltration analysis,prediction of upstream microRNAs(miRNAs)and long noncoding RNAs(lncRNAs)of ING1,and ING1-related gene functional enrichment analysis)was applied to study the expression profile,clinical relationship,prognostic significance and immune infiltration of ING in LIHC.The relationship between ING family genes expression and tumor associated immune checkpoints was investigated in LIHC.The molecular mechanism of ING1 mediated hepatocarcinogenesis was preliminarily discussed.RESULTS mRNA/protein expression of different ING family genes in LIHC was analyzed in different databases,showing that ING family genes were highly expressed in LIHC.In 47 samples from 366 LIHC patients,the ING family genes were altered at a rate of 13%.By comprehensively analyzing the expression,clinical pathological parameters and prognostic value of ING family genes,ING1/5 was identified.ING1/5 was related to poor prognosis of LIHC,suggesting that they may play key roles in LIHC tumorigenesis and progression.One of the target miRNAs of ING1 was identified as hsa-miR-214-3p.Two upstream lncRNAs of hsa-miR-214-3p,U91328.1,and HCG17,were identified.At the same time,we found that the expression of ING family genes was correlated with immune cell infiltration and immune checkpoint genes.CONCLUSION This study lays a foundation for further research on the potential mechanism and clinical value of ING family genes in the treatment and prognosis of LIHC. 展开更多
关键词 Liver cancer ing family genes Noncoding RNAs Immune cell infiltration PROGNOSIS
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Machining of a film-cooling hole in a single-crystal superalloy by high-speed electrochemical discharge drilling 被引量:13
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作者 Zhang Yan Xu Zhengyang +1 位作者 Zhu Yun Zhu Di 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第2期560-570,共11页
Single-crystal superalloys are typical advanced materials used for manufacturing aero- engine turbine blades. Their unique characteristics of high hardness and strength make them exceedingly difficult to machine. Howe... Single-crystal superalloys are typical advanced materials used for manufacturing aero- engine turbine blades. Their unique characteristics of high hardness and strength make them exceedingly difficult to machine. However, a key structure of a turbine blade, the film-cooling hole, needs to be machined in a single-crystal superalloy; such machining is challenging, especially considering the increasing levels of machining efficiency and quality demanded by the aeroengine industry. Tube electrode high-speed electrochemical discharge drilling (TSECDD), a hybrid technique of high-speed electrical discharge drilling and electrochemical machining, provides high machining efficiency and accuracy, as well as eliminating the recast layer. In this study, TSECDD is used to machine a film-cooling hole in a nickel-based single-crystal superalloy (DD6). The Tagu- chi methods of experiment are used to optimise the machining parameters. Experimental results show that TSECDD can effectively drill the film-cooling hole; the optimum parameters that give the best performance are as follows: pulse duration: 12μs, pulse interval: 30 gs, peak current: 6 A, and salt solution conductivity: 3 mS/cm. Finally, a hole is machined by TSECDD, and the results are compared with those obtained by electrical discharge machining. TSECDD is found to be promising for improving the surface quality and eliminating the recast layer. 展开更多
关键词 Electrical discharge machin-ing (EDM) Electrochemical machining(ECM) Film-cooling hole Hybrid technique Single crystal Taguchi methods
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<i>In vitro</i>Bile Acid Binding of Mustard Greens, Kale, Broccoli, Cabbage and Green Bell Pepper Improves with Sautéing Compared with Raw or Other Methods of Preparation 被引量:1
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作者 Talwinder S. Kahlon Rebecca R. Milczarek Mei-Chin M. Chiu 《Food and Nutrition Sciences》 2012年第7期951-958,共8页
Bile acid binding potential of foods and food fractions has been related to lowering the risk of heart disease and that of cancer. Steam cooking has been observed to significantly improve bile acid binding of green/le... Bile acid binding potential of foods and food fractions has been related to lowering the risk of heart disease and that of cancer. Steam cooking has been observed to significantly improve bile acid binding of green/leafy vegetables. It was hypothesized that other cooking methods could further improve the bile acid binding of various vegetables. Sautée cooking resulted in in vitro bile acid binding measured on a dry matter basis relative to cholestyramine of 14% for mustard greens and kale, 9% for broccoli, 8% for collard greens, 6% for cabbage, and 5% for green bell pepper. These results point to the significantly different (P ≤ 0.05) health promoting potential of mustard greens = kale > broccoli > collard greens > cabbage > green bell pepper. Sautéing significantly improved in vitro bile acid binding of mustard greens, kale, broccoli, cabbage and green bell pepper compared with steaming, boiling or raw (uncooked). Collard greens exhibited significantly higher bile acid binding by steaming compared with sautéing, boiling or raw. Data suggest that the cooking method with most heath promoting potential for mustard greens, kale, broccoli, cabbage and green bell pepper should be sautéing. Steaming should be used for collard greens as the cooking method. These green/leafy vegetables, when consumed regularly after sautéing, would promote a healthy lifestyle and have the potential to lower the risk of premature degenerative diseases. 展开更多
关键词 In vitro Bile Acid Binding Mustard Greens KALE BROCCOLI CABBAGE Green Bell Pepper and Collard Greens Sautéing STEAMing Boiling
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p33ING1b和p53在银屑病和基底细胞癌中的表达及临床意义 被引量:6
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作者 贺琪 岳青 +3 位作者 皮先明 石全 陈宏翔 李家文 《实用医学杂志》 CAS 北大核心 2014年第9期1391-1394,共4页
目的:探讨肿瘤抑制因子p53和生长抑制因子p33ING1b在人类银屑病和基底细胞癌(basal cell carcinoma,BCC)中的表达情况及临床意义。方法 :采用免疫组织化学Envision方法检测p53和p33ING1b在36例寻常型银屑病皮损(银屑病组)、28例BCC皮损(... 目的:探讨肿瘤抑制因子p53和生长抑制因子p33ING1b在人类银屑病和基底细胞癌(basal cell carcinoma,BCC)中的表达情况及临床意义。方法 :采用免疫组织化学Envision方法检测p53和p33ING1b在36例寻常型银屑病皮损(银屑病组)、28例BCC皮损(BCC组)和14例正常表皮(正常对照组)中的蛋白表达。结果:p53在正常对照组、银屑病组和BCC组中表达递增,p33ING1b在3组中表达递减,组间比较差异均有显著性(均P<0.05)。银屑病组和BCC组中,p53与p33ING1b之间均存在显著正相关(均P<0.05)。结论:p53和p33ING1b协同作用于增生性皮肤病的局部皮损,是细胞异常增殖的重要机制之一。 展开更多
关键词 P53 P33ing1B 银屑病 基底细胞癌 ing1
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ING4基因对人胃癌细胞SGC-7901生物行为的影响 被引量:8
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作者 黄俊琼 孙万邦 +1 位作者 张海峰 杨吉成 《中国免疫学杂志》 CAS CSCD 北大核心 2008年第7期612-614,617,共4页
目的:研究人ING4对人胃癌细胞SGC-7901的影响,探讨其作用机制。方法:将重组腺病毒质粒pAd-ING4用PacI线性化,经脂质体转染QBI-293A细胞,获得重组病毒Ad-ING4。Ad-ING4感染人SGC-7901细胞,RT-PCR及Western blot分析ING4和p21表达,MTT法检... 目的:研究人ING4对人胃癌细胞SGC-7901的影响,探讨其作用机制。方法:将重组腺病毒质粒pAd-ING4用PacI线性化,经脂质体转染QBI-293A细胞,获得重组病毒Ad-ING4。Ad-ING4感染人SGC-7901细胞,RT-PCR及Western blot分析ING4和p21表达,MTT法检测Ad-ING4对细胞生长的影响,激光共聚焦显微镜检测细胞凋亡。结果:Ad-ING4感染后,SGC-7901细胞中有ING4 mRNA和蛋白质表达,细胞生长受到明显抑制,与野生型SGC-7901细胞相比,p21表达水平增高,细胞凋亡率明显增高,P<0.05。结论:ING4可通过上调p21表达发挥抑制SGC-7901细胞生长、诱导细胞凋亡的作用。 展开更多
关键词 ing4 AD-ing4 人SGC-7901细胞 P21
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Stabilization Variable Structure Control for Singular Decoupling Motor System
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作者 Zou, Wenxun Liu, Yongqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第1期65-72,共8页
This paper describes the important application of variable structure control (VSC) theory on induction motor (IM) decoupling control system. A design scheme using singular system variable structure control method for ... This paper describes the important application of variable structure control (VSC) theory on induction motor (IM) decoupling control system. A design scheme using singular system variable structure control method for a decoupling IM system is presented. The scheme is shown to be robust to parametric variations and external disturbances. Simulation results show the stability and effectiveness of the proposed scheme 展开更多
关键词 Singular system Sliding mode Variable structure control Decoupling control Switch- ing function.
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大肠癌中抑癌基因p33/ING1 mRNA的表达及意义 被引量:3
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作者 王自强 蔡志民 余佩武 《第三军医大学学报》 CAS CSCD 北大核心 2001年第3期349-351,共3页
目的 了解p33/ING1表达与大肠癌临床病理特征的关系及其可能作用机制。方法 采用逆转录PCR检测 5 2例散发性大肠癌癌组织及正常大肠粘膜中ING1的表达。结果 在大肠癌组织中p33/ING1mRNA表达较正常粘膜明显减弱 ( 30 /5 2 ,5 7.7% ) ,... 目的 了解p33/ING1表达与大肠癌临床病理特征的关系及其可能作用机制。方法 采用逆转录PCR检测 5 2例散发性大肠癌癌组织及正常大肠粘膜中ING1的表达。结果 在大肠癌组织中p33/ING1mRNA表达较正常粘膜明显减弱 ( 30 /5 2 ,5 7.7% ) ,p33/ING1的低表达与肿瘤的Duke’s分期及淋巴结转移显著相关。 展开更多
关键词 结直肠癌 抑癌基因 ing1 RT-PCR 大肠癌 P33/ing1 MRNA
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RE而意用ECO-WORKING“环乐同创”
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作者 灰原 《中国自行车》 2024年第4期90-93,共4页
2024年5月1日至6月2日,RE而意与小布(BROMPTON)、FREITAG、抱朴再生BOTTLOOP合作,在上海张园呈现了一场精彩纷呈的展览。本次展览的主题为“ECO-WORKING!环乐同创”。展览以“倡导时尚、环保、可持续的生活方式”为主导,展现一系列具有... 2024年5月1日至6月2日,RE而意与小布(BROMPTON)、FREITAG、抱朴再生BOTTLOOP合作,在上海张园呈现了一场精彩纷呈的展览。本次展览的主题为“ECO-WORKING!环乐同创”。展览以“倡导时尚、环保、可持续的生活方式”为主导,展现一系列具有长效设计、实用、可循环利用且令人愉悦的时尚单品。 展开更多
关键词 可循环利用 ing ECO 可持续的
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Most relevant weighted filtering with one-step singular correlation recognition
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作者 刘超 蔡建超 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期328-332,共5页
Based on the recognition of one-step singular correlation and the remedying methods obtained before,the correlation properties of the neighborhood pixels and the characteristics of image de-noising were analyzed.A kin... Based on the recognition of one-step singular correlation and the remedying methods obtained before,the correlation properties of the neighborhood pixels and the characteristics of image de-noising were analyzed.A kind of most relevant weighted filtering method based on one-step singular correlation recognition(OSSC-MRWF)was put forward.The simulation experiments were done and the comparison with some commonly used methods under salt-and-pepper noises was made.The results show that the proposed method can not only effectively recognize salt-and-pepper noises and mend up the noise points,but also protect the original information such as the edge details very well.The accuracy and performance indicators are further improved considerably. 展开更多
关键词 correlation function image filtering one-step singular correlation singular value recognition weighted filter- ing salt-and-pepper noise
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the Roll’ING进京 网红品牌如何才能长红
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作者 郭缤璐 张天元 《中国食品》 2024年第7期123-125,共3页
动排队数小时的网红瑞士卷进京,是真需求还是饥饿营销的话题也再次引发热议。近日,上海网红瑞土卷烘培品牌the Roll'ING手作瑞士卷专门店在朝阳大悦城开出北京首店,并迅速在社交平台上走红,不乏出现排队时间长、出餐效率低、黄牛加... 动排队数小时的网红瑞士卷进京,是真需求还是饥饿营销的话题也再次引发热议。近日,上海网红瑞土卷烘培品牌the Roll'ING手作瑞士卷专门店在朝阳大悦城开出北京首店,并迅速在社交平台上走红,不乏出现排队时间长、出餐效率低、黄牛加价乱象等吐槽,不少消费者直呼是“饥饿营销”。值得注意的是,这家品牌同样出自于网红烘培品牌KUMOKUMO创始人姜浩文之手,此前上海首店开业时也受到“口碑危机”。 展开更多
关键词 饥饿营销 社交平台 烘培 大悦城 ing 网红 品牌 排队时间
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名词(动词)+-ing的含义
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作者 宗福常 《语言教育》 1996年第3期21-22,共2页
我们知道,在动词词尾加上-ing 便构成动词的现在分词或动名词,表示动作。此外.有些动名词还可能是一个可数名词,表事物,如:a Chinese painting 一幅中国画strong buildings 坚固的建筑物然而,-ing 结尾的动名词也有用来表示一类事物总... 我们知道,在动词词尾加上-ing 便构成动词的现在分词或动名词,表示动作。此外.有些动名词还可能是一个可数名词,表事物,如:a Chinese painting 一幅中国画strong buildings 坚固的建筑物然而,-ing 结尾的动名词也有用来表示一类事物总称的。 展开更多
关键词 ing 现在分词 painting 集合名词 ADVERTISEMENT ADVERTISing false 屋面材料 FUNDing 厚木
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β-连环蛋白与抑癌基因ING1蛋白在肺癌组织中的表达 被引量:1
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作者 曾凡军 周媛媛 +3 位作者 宋新宇 熊晓琦 赵必君 陈世雄 《疑难病杂志》 CAS 2012年第2期110-112,F0003,共4页
目的观测β-连环蛋白(β-catenin)及抑癌基因ING1的蛋白表达产物p33^(ING1)在肺癌中的表达。方法纳人40例肺癌组织标本(肺癌组)和10例正常肺组织标本(对照组),采用免疫组化SP法检测β-catenin及p33^(ING1)蛋白在2组中的表达,并分析p33^(... 目的观测β-连环蛋白(β-catenin)及抑癌基因ING1的蛋白表达产物p33^(ING1)在肺癌中的表达。方法纳人40例肺癌组织标本(肺癌组)和10例正常肺组织标本(对照组),采用免疫组化SP法检测β-catenin及p33^(ING1)蛋白在2组中的表达,并分析p33^(ING1)蛋白表达与肺癌临床病理特征的关系。结果肺癌组和对照组p33^(ING1)阳性表达率分别为57.5%和100.0%,2组差异有统计学意义(P<0.05)。肺癌组中β-catenin阳性表达率为81.2%,异常表达率为64.4%,p33^(ING1)与β-catenin阳性表达率呈正相关(r=0.6324,P<0.05)。p33^(ING1)表达与性别、年龄、病理组织学类型等无关(P>0.05),而与分化程度、TNM分期、有无淋巴结转移等有关(P<0.05)。结论β-eatenin的异常表达及p33^(ING1)表达与肺癌发生发展密切相关;联合检测其表达水平的变化对肺癌的早期诊断、恶性程度判断及基因介导治疗等方面均有重要指导意义。 展开更多
关键词 肺肿瘤 Β-连环蛋白 抑癌基因ing1 p33~ing1蛋白 免疫组织化学
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A Machine Learning-Based Web Application for Heart Disease Prediction
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作者 Jesse Gabriel 《Intelligent Control and Automation》 2024年第1期9-27,共19页
This work leveraged predictive modeling techniques in machine learning (ML) to predict heart disease using a dataset sourced from the Center for Disease Control and Prevention in the US. The dataset was preprocessed a... This work leveraged predictive modeling techniques in machine learning (ML) to predict heart disease using a dataset sourced from the Center for Disease Control and Prevention in the US. The dataset was preprocessed and used to train five machine learning models: random forest, support vector machine, logistic regression, extreme gradient boosting and light gradient boosting. The goal was to use the best performing model to develop a web application capable of reliably predicting heart disease based on user-provided data. The extreme gradient boosting classifier provided the most reliable results with precision, recall and F1-score of 97%, 72%, and 83% respectively for Class 0 (no heart disease) and 21% (precision), 81% (recall) and 34% (F1-score) for Class 1 (heart disease). The model was further deployed as a web application. 展开更多
关键词 Heart Disease US Center for Disease Control and Prevention Machine Learn-ing Imbalanced Data Web Application
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New Precoded Spatial-Multiplexing for an Erasure Event in Single Frequency Networks
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作者 hojun kim seyoung kim +2 位作者 yulong shang seunghyeon kim taejin jung 《China Communications》 SCIE CSCD 2018年第4期130-140,共11页
In this paper, we propose a new spatial-multiplexing(SM) scheme employing an orthogonal precoder over Rayleigh-fading channels for an erasure event in single frequency networks(SFN). To optimize the precoder, the aver... In this paper, we propose a new spatial-multiplexing(SM) scheme employing an orthogonal precoder over Rayleigh-fading channels for an erasure event in single frequency networks(SFN). To optimize the precoder, the average bit error rate(BER) is evaluated and minimized through a mathematical analysis. Compared to an ordinary SM, the proposed scheme guarantees identical BER performance under non-erasure fading channels and achieves a greatly improved performance under erasure fading channels, especially for a higher erasure-ratio and SNR values. This improvement is mainly due to the increase in the diversity gain incurred by the optimized precoder over the erasure event. We also compare the performance of the proposed SM to that of the conventional constellation-rotation(CR) scheme applied to the single antenna SFN systems. The results of a computer simulation show that the performance of the new scheme is more effective than that of a conventional CR across all simulation cases. 展开更多
关键词 Spatial-multiplexing single fre-quency network Rayleigh fading constella-tion-rotation broadcasting systems.
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ING1基因与肿瘤的研究新进展 被引量:1
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作者 赵帅 贺修胜 《医学综述》 2005年第5期444-446,共3页
关键词 ing1基因 P53基因 肿瘤 ing基因家族
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Study on New Nano Sun Shading Films
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作者 王佳 周宁琳 +6 位作者 朱小玲 苏玉天 邵毛妮 田璐 张明 李文秀 陈园园 《Agricultural Science & Technology》 CAS 2015年第8期1816-1819,共4页
[Objective] The research developed a new kind of nano sun shading films that can be used in summer to maintain the appropriate indoor temperature for crops. [Method] The nano sun shading films were prepared by interca... [Objective] The research developed a new kind of nano sun shading films that can be used in summer to maintain the appropriate indoor temperature for crops. [Method] The nano sun shading films were prepared by intercalation method. The films were characterized by XRD, TG, FA, UV-Vis-NIR and outdoor temperature test. [Result] Based on evaluation of cooling efficiency, a reduction 3-4 ℃ can be observed in newly developed nano sun shading films compared to control film. This film can control greenhouse light intensity effectively and decrease indoor tempera- ture, providing crops with appropriate growing temperature by reflecting most of in- frared light. Moreover, part of incident light can be converted to blue light and red light, which is beneficial to photosynthesis in plant. [Conclusion] Agricultural film is an important component to agriculture industry. Thus, agricultural film with improved properties and low cost has a broad application prospect. 展开更多
关键词 FILM Coo/ing SHADing Light Scattering synergism
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