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Colombian Migration and the Body Mass Index: The Relationship between Migration and Weight Gain among Colombian Migrants
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作者 Michael B. Aguilera 《Food and Nutrition Sciences》 2023年第11期1078-1093,共16页
The Latin American Migration Project-Colombia is used to study the Body Mass Index (BMI) of Colombian migrants to determine whether their BMI score increased the longer they were abroad. The study contributes to the l... The Latin American Migration Project-Colombia is used to study the Body Mass Index (BMI) of Colombian migrants to determine whether their BMI score increased the longer they were abroad. The study contributes to the literature on BMI by studying Colombian migrants, an understudied migrant group. Duration of trip is used as a measure of acculturation. The study also evaluates the claim that trip duration is a measure of acculturation using data specific to migrants, which shows that trip duration is an adequate proxy measure of acculturation. The study includes current migrants, returned migrants and non-migrants. The study accounts for the selectivity of migration by comparing migrants to non-migrants, as some studies highlight the health selectivity of migration. The study uses multinomial regression to test whether the probability of being overweight and/or obese is associated with spending more time abroad. Consistent with studies conducted within the receiving countries, the study finds that increased duration of trip is positively and significantly associated with the probability of being overweight and obese. Furthermore, the study also shows that among return migrants there is a negative relationship between time they had remained in Colombia and probability of being obese. The findings show that migrants put on weight while abroad and lose that weight the longer they remain in Colombia. The findings show that place has an indelible impact on health through migrant’s weight. 展开更多
关键词 Body mass index migration Colombia ACCULTURATION
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Soxllb regulates the migration and fate determination of Müller glia-derived progenitors during retina regeneration in zebrafish 被引量:1
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作者 Kaida Song Zihao Lin +5 位作者 Lining Cao Bowen Lu Yuxi Chen Shuqiang Zhang Jianfeng Lu Hui Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期445-450,共6页
The transcription factor Sox11 plays important roles in retinal neurogenesis during vertebrate eye development.However,its function in retina regeneration remains elusive.Here we report that Sox11 b,a zebrafish Sox11 ... The transcription factor Sox11 plays important roles in retinal neurogenesis during vertebrate eye development.However,its function in retina regeneration remains elusive.Here we report that Sox11 b,a zebrafish Sox11 homolog,regulates the migration and fate determination of Müller glia-derived progenitors(MGPCs)in an adult zebrafish model of mechanical retinal injury.Following a stab injury,the expression of Sox11 b was induced in proliferating MGPCs in the retina.Sox11 b knockdown did not affect MGPC formation at 4 days post-injury,although the nuclear morphology and subsequent radial migration of MGPCs were alte red.At 7 days post-injury,Sox11 b knockdown res ulted in an increased proportion of MGPCs in the inner retina and a decreased propo rtion of MGPCs in the outer nuclear layer,compared with controls.Furthermore,Sox11 b knockdown led to reduced photoreceptor regeneration,while it increased the numbe rs of newborn amacrines and retinal ganglion cells.Finally,quantitative polymerase chain reaction analysis revealed that Sox11 b regulated the expression of Notch signaling components in the retina,and Notch inhibition partially recapitulated the Sox11 b knockdown phenotype,indicating that Notch signaling functions downstream of Sox11 b.Our findings imply that Sox11 b plays key roles in MGPC migration and fate determination during retina regeneration in zebrafish,which may have critical im plications for future explorations of retinal repair in mammals. 展开更多
关键词 cell migration fate determination müllerglia müller glia-derived progenitor Notch signaling photoreceptor retina regeneration Sox11 transcription factor ZEBRAFISH
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Simulation of dilatancy-controlled gas migration processes in saturated bentonite using a coupled multiphase flow and elastoplastic H2 M model
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作者 Eike Radeisen Hua Shao +3 位作者 Jürgen Hesser Olaf Kolditz Wenjie Xu Wenqing Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期803-813,共11页
Dilatancy-controlled gas flow in preferential pathways plays a key role in the safety analysis of radioactive waste repositories.This is particularly the case for bentonite,an often-preferred barrier material.Gas flow... Dilatancy-controlled gas flow in preferential pathways plays a key role in the safety analysis of radioactive waste repositories.This is particularly the case for bentonite,an often-preferred barrier material.Gas flow in preferential pathways is characterized by localization and spontaneous behavior,which is challenging to simulate in numerical models due to strong hydro-mechanical coupling.To analyze a laboratory experiment in the framework of the DECOVALEX-2023 project,this study introduced a new approach of combining continuous modelling methods with spatial material properties derived from material heterogeneities and experimental observations.The proposed model utilized hydro-mechanical spatial distributions,namely Young’s modulus and gas entry pressure,and elastoplasticity combined with a linear swelling model.A conceptual strain-dependent permeability approach simulated dilatancycontrolled gas flow based on hydro-mechanical coupling.To test the effectiveness of the presented approach,a gas injection test in a compacted,saturated bentonite sample was simulated using the opensource code OpenGeoSys 5.8 and compared with experimental observations.The presented methodology is capable of simulating localized gas flow in preferential pathways.The spatial distributions of Young’s modulus and gas entry pressure affect the swelling pressure,relative permeability and,in combination with the strain-dependent permeability model,also the intrinsic permeability. 展开更多
关键词 H^(2)m coupling Gas migration Dilatancy-controlled flow Continuous approach Geomaterial heterogeneity OPENGEOSYS
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Benefit evaluation of the Three-Gorges Reservoir migration by an assessment index model based on analytic hierarchy process 被引量:1
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作者 WANG Jun-hui GAN Lian-jun 《Journal of Chongqing University》 CAS 2007年第2期100-106,共7页
An assessment index model was established to evaulate the benefit of the Three-Gorges Reservoir migration through the analytical hierarchy process. Totally 43 indicators were selected to assess the impact of migration... An assessment index model was established to evaulate the benefit of the Three-Gorges Reservoir migration through the analytical hierarchy process. Totally 43 indicators were selected to assess the impact of migration on the economic, social and ecological environmental aspects of the migration communities, with the data of the indicators of the years 1992, 1998, 2002 which represented the period of premigration, the end of the first phase migration and the end of the second phase migration, respectively. The evaluation matrix is sufficiently consistent, with a consistency ratio CR equal to 0.086 3. The assessment turned out a benefit value for the economic subsystem in the year 2004 larger than triple the value in the year 1992, indicating a remarkable economic growth in the Reservoir area. The constantly increasing value for the social subsystem reflects the stable social situations. There is a slight decline in the assessment outcome of the ecological subsystem for the year 1998, which implies enviromental conservation was given insufficient importance during that period. On the whole, the implementation of the migration project is favorable to the Reservoir region, as confirmed by the stably increasing overall evaluation value from 42.22% in 1992 to 68.81% in 2002. However, there is still much room to improve from the status quo to the target criteria. 展开更多
关键词 三峡水库 移民工程 效益评估 分析方法
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Peterson图和图D_(m,n)的边PI指数
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作者 张丽 张辉 红霞 《宁夏师范学院学报》 2024年第4期5-15,共11页
利用分析法和分类讨论法,给出Peterson图和D_(m,n)图的边PI指数计算公式,丰富了图的PI指数理论.
关键词 边PI指数 Peterson图 图Dm N
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基于AMBI和M-AMBI法的桑沟湾底栖生态环境质量评价
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作者 李文豪 于晓清 +4 位作者 蒋增杰 杜美荣 贾彦 何为 高亚平 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期55-67,共13页
养殖环境评价是衡量海水养殖活动是否健康、可持续的重要环节。为掌握北方典型规模化养殖海湾——桑沟湾沉积环境质量状况,于2017年4和7月对桑沟湾全湾海域进行大型底栖动物走航调查取样,分析了大型底栖动物的种类组成、生物量、栖息密... 养殖环境评价是衡量海水养殖活动是否健康、可持续的重要环节。为掌握北方典型规模化养殖海湾——桑沟湾沉积环境质量状况,于2017年4和7月对桑沟湾全湾海域进行大型底栖动物走航调查取样,分析了大型底栖动物的种类组成、生物量、栖息密度及群落结构;运用AMBI(AZTI’s marine biotic index)指数法和M-AMBI(Multivariate-AMBI)指数法,分析了大型底栖动物群落受干扰程度,评价了沉积环境质量状况。研究表明,在两次调查中多毛类均为优势种,其中4月多毛类36种,占总种数63.16%;7月32种,占总种数的60.38%。AMBI法的评估结果表明,调查海域各站位以受到轻度扰动为主,个别站位受到中度扰动和无扰动,干扰程度从小到大依次为海带区<海草区<混养区<贝类区;M-AMBI法的评估结果表明,生态环境质量等级为良或优的站位占60.00%~68.42%,海草区环境质量状况要明显好于养殖区。多营养层次综合养殖模式缓解了桑沟湾近海生态系统的养殖压力,使得桑沟湾受人为干扰较小,海草区环境质量为优,贝类区、混养区和海带区的环境质量处于中等和良之间。 展开更多
关键词 桑沟湾 大型底栖动物 AmBI指数 m-AmBI指数 底栖生态环境质量
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The effects and mechanisms of cytoplasmic Macrophage colony-stimulating factor (M-CSF) on the proliferation,migration and invasion of HeLa cells
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作者 ZHANG Meng-xia2,WU Hai-yan1,TU Jian1,ZHANG Xiao-hong2,LE Xiao-yong1,TANG Sheng-song1,2(1.Institute of Pharmacy and Pharmacology,University of South China,Hengyang 421001,China 2.Center for Life Sciences,University of South China,Hengyang 421001,China) 《沈阳药科大学学报》 CAS CSCD 北大核心 2008年第S1期86-87,共2页
Objective To explore the effects and mechanisms of cytoplasmic M-CSF on the proliferation,migration and invasion of HeLa cells.Methods Both pCMV/cyto/myc vector and pCMV/cyto/myc-M-CSF vector was transfected into HeLa... Objective To explore the effects and mechanisms of cytoplasmic M-CSF on the proliferation,migration and invasion of HeLa cells.Methods Both pCMV/cyto/myc vector and pCMV/cyto/myc-M-CSF vector was transfected into HeLa-cell by transfectaimine.After screening by G418,the positive clones were amplified and confirmed by RT-PCR,Western blot and immunocytochemistry.The effect of cytoplasmic M-CSF on the proliferation of HeLa cells were analyzed by cell conuting and antisense oligonucleotides.The migration and invasion of cell was measured by in vitro Transwell assay and Matrigel-coated polycarbonate filters.The expression of cyclinE,cyclinD1/2/3,CDK2/4/6,Rac1,and matrix metalloproteinase 2 and 9(MMP2/9)were assayed by semiquantitative RT-PCR.And expression of both α-tubulin and cdc42 were displayed by immunofluorescence.The activity of MMP2 was detected by gelatin zymography.Results Results A cell line(referred as to HeLa-M cell)that highly expresses cytoplasmic M-CSF was successfully established in the test.Our result indicated that HeLa-M cell had a larger volume,faster growth rate and shorter doubling time than either pCMV/cyto/myc transfected HeLa cells(referred as to HeLa-C cell)or untransfected HeLa cells(referred as to HeLa cell).M-CSF-specific antisense oligonucleoside significantly inhibited HeLa-M cell proliferation and had little effect on either HeLa-C cell or HeLa-C cell growth.Cytoplasmic M-CSF up-regulated both the expression of cyclinE,cyclinD1 and cyclinD3,CDK2,CDK 4 and CDK6,a Rho GTPase ralative protein(Rac1),cdc42 and MMP2,but had little effect on expression of MMP9 and cyclin D2.Furthermore,cytoplasmic M-CSF induced the rearrangement of the α-tubulin in HeLa cells and significantly promoted the migration and invasion of HeLa cells in vitro.Conclusions Cytoplasmic M-CSFs up-regulate the expression of cyclinE,cyclinD1 and cyclinD3,CDK2,CDK 4 and CDK6 and induces the proliferation of HeLa cells.Cytoplasmic M-CSFs up-regulate the expression of Rac1 and cdc42 and cause the rearrangement of the α-tubulin in HeLa cells.Furthermore Cytoplasmic M-CSFs increase both the expression and activity of MMP2 and promote the migration and invasion of HeLa cell in vitro.But cytoplasmic M-CSFs have little effect on expression of cyclin D2 and MMP9. 展开更多
关键词 m-CSF HELA cell line CYTOSKELETON migration INVASION
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Ray equation migration of wide-angle reflections in Dabie orogenic zone
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作者 郑需要 王椿镛 +1 位作者 赖晓玲 张先康 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期63-72,共10页
ay equation migration of wide-angle reflections in 2-D medium is one kind of Kirchhoff prestack depth migration method. Based on ray theory, this method can be used extensively in 2-D inhomogeneous medium, and shows i... ay equation migration of wide-angle reflections in 2-D medium is one kind of Kirchhoff prestack depth migration method. Based on ray theory, this method can be used extensively in 2-D inhomogeneous medium, and shows its advantage in wide-angle reflection study. After calculating ray fields, we can get the wave fields of sources and receivers by interpolation, and the intensity (or amplitude) AP corresponding to the depth point P at travel-time tP=tSP+tPR can be found in seismograms. Ray equation migration is completed by transforming AP according to the specific relation, migrating it to the depth point, then calculating the ray fields of lots of sources and receivers in the same way and finally stacking the outcomes. Numerical calculation has yielded satisfactory results. Data processing of the Zhuangmu-Yuexi-Huangmei-Zhanggongdu profile passing through the Dabie orogenic zone provides a structural form of M-discontinuity along the profile. The result shows that the high pressure metamorphic rock zone of South Dabie rock mass is related to the uplifting of M-discontinuity here. 'Mountain root' exists under North Dabie rock mass, which conforms with gravity isostasy theory. The Xiaotian-Mozitan fault is a suture zone as a result of the collision of North China plate with Yangtze plate, and extends through M-discontinuity. The abyssal fault near Liu'an is the extended eastern section of the Luonan-Minggang fault, which is also confirmed here. 展开更多
关键词 ray equation migration seismic profile m-discontinuity abyssal fault Dabie orogenic zone
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M*(k)-index构造算法的改进
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作者 任家东 马瑞 《计算机工程》 CAS CSCD 北大核心 2008年第19期58-60,共3页
一些基于图结构的索引技术通过缩小查询范围提高对XML数据的查询速度,但存在分隔不相关节点的问题。该文改进M*(k)-index的构造算法,用单一的M**(k)-index结构取代原算法的序列结构,以避免存储序列成员中的节点与边及序列成员之间的链接... 一些基于图结构的索引技术通过缩小查询范围提高对XML数据的查询速度,但存在分隔不相关节点的问题。该文改进M*(k)-index的构造算法,用单一的M**(k)-index结构取代原算法的序列结构,以避免存储序列成员中的节点与边及序列成员之间的链接,提高其存储性能和查询效率。实验结果表明,改进后的结构具有良好性能。 展开更多
关键词 XmL数据 索引结构 m*(k) -index结构
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A comparison of the applicability of the Shannon-Wiener index,AMBI and M-AMBI indices for assessing benthic habitat health in the Huanghe(Yellow River) Estuary and adjacent areas 被引量:5
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作者 LUO Xianxiang SUN Kaijing +2 位作者 YANG Jianqiang SONG Wenpeng CUI Wenlin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期50-58,共9页
From a dataset of macrobenthos obtained from 18 cruises from 2004 to 2013 in the Huanghe(Yellow River)Estuary and its adjacent areas,the composition and characteristics of macrobenthos were analyzed,and the applicab... From a dataset of macrobenthos obtained from 18 cruises from 2004 to 2013 in the Huanghe(Yellow River)Estuary and its adjacent areas,the composition and characteristics of macrobenthos were analyzed,and the applicability of the Shannon-Wiener Index(H′),AZTI's Marine Biotic Index(AMBI) and multivariate AMBI(MAMBI) for assessing benthic habitat quality was compared.The results showed a total of 203 macrobenthos in the study area.The macrobenthos were dominated by polychaetes,followed by mollusks and crustaceans.The macrobenthic ecological groups were dominated by EGI,EGII and EGIII,which respectively accounted for 31.5%,36.0% and 21.2% of the total.There were significant differences between the evaluation results of the three indices.The ecological quality status(EQS) levels given by the AMBI were greater than those given by the H′ and M-AMBI.The AMBI could not reflect the differences between 11 sites but the H′ and M-AMBI could do.Moreover,the three indices responded well to the variations in salinity(S) and dissolved oxygen(DO) in the waters.The H′ and MAMBI also responded sensitively to the differences in physical parameters,such as water depth and sediment texture.The correlation between M-AMBI and environmental pressure gradient data was the strongest.The MAMBI could effectively distinguish degraded conditions from undegraded but the H′ and AMBI could not.Therefore,the M-AMBI reflected benthic habitat health well in the study areas.However,the objectivity of evaluation results of M-AMBI needs further verification by physical,chemical and biological methods.The thresholds also need further discussion. 展开更多
关键词 mACROBENTHOS ecological quality status Huanghe Estuary Shannon-Wiener index AmBI m-AmBI
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Migrated Exploding Reflectors in Evaluation of Finite Difference Solution for Inhomogeneous Seismic Models
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作者 Maryam Nejati Hosein Hashemi 《Engineering(科研)》 2012年第12期950-957,共8页
Earth is inhomogeneous, which means its elastic characteristics change with depth. The seismic method employs the propagation of waves throughout the earth to locate different structures and stratigraphy. Understandin... Earth is inhomogeneous, which means its elastic characteristics change with depth. The seismic method employs the propagation of waves throughout the earth to locate different structures and stratigraphy. Understanding the wave propagation is an important matter in exploration seismology;therefore modeling of seismic wave is an important tool. To validate the interpreted earth model out of the seismic data, seismic synthetic seismograms should be generated in a process named “seismic forward modeling”. Finite difference method is used as one of the most common numerical modeling techniques. In this paper the accuracy of finite difference method in seismic section modeling is explored on different modeled data set of heterogeneous earth. It is shown that finite difference method completes with migration to reposition the events in their correct location. Two different migration methods are used and various velocities are also tested to determine an appropriate migration velocity. Finally the validly of finite difference modeling is examined using a 2D structural similarity index technique. 展开更多
关键词 Finite DIFFERENCE method SEISmIC modeling migration Exploding REFLECTOR Structural SImILARITY index
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基于最小数据集权重(MDS)的稀土土壤质量评价研究
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作者 贾志兴 江磊 +1 位作者 陈明 黄蕾 《环境生态学》 2023年第1期1-6,共6页
为研究稀土矿区周边土壤质量状况以及稀土元素的迁移效果,以赣州市定南某稀土矿区周边土壤和植物为研究对象,分别研究了稀土元素在当地土壤稀土背景浓度下的迁移能力以及在稀土地球化学背景值下的综合迁移能力。结果表明:镝的迁移效果最... 为研究稀土矿区周边土壤质量状况以及稀土元素的迁移效果,以赣州市定南某稀土矿区周边土壤和植物为研究对象,分别研究了稀土元素在当地土壤稀土背景浓度下的迁移能力以及在稀土地球化学背景值下的综合迁移能力。结果表明:镝的迁移效果最好;单位质量植物的迁移效果研究中,稀土元素向栀子花的迁移效果最好。同时,利用主成分分析对测定的土壤指标进行筛选,构建最小数据集,从而计算得到全数据集土壤质量指数(SQI-T)、重要数据集土壤质量指数(SQI-I)和最小数据集土壤质量指数(SQI-M)。根据得到的SQI-T与SQI-M相关性分析,检验最小数据集权重(MDS)的合理性,最终结果显示MDS在土壤评价上有较良好的应用潜力。 展开更多
关键词 稀土迁移 最小数据集 土壤质量评价 土壤质量指数
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基于MRSEI模型的阿勒泰市生态环境时空变化及驱动力分析 被引量:1
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作者 刘笑 郭鹏 +3 位作者 祁佳峰 杜文玲 张茹倩 张坤 《干旱区研究》 CSCD 北大核心 2023年第6期1014-1026,共13页
为及时、客观、定量地评估新疆阿勒泰市生态环境,研究基于多源遥感数据构建改进型遥感生态指数(MRSEI)结合标准差椭圆和重心迁移模型分析其时空变化特征,并使用地理探测器模型对绿度、干度、湿度、温度和空气质量5个指标进行因子探测。... 为及时、客观、定量地评估新疆阿勒泰市生态环境,研究基于多源遥感数据构建改进型遥感生态指数(MRSEI)结合标准差椭圆和重心迁移模型分析其时空变化特征,并使用地理探测器模型对绿度、干度、湿度、温度和空气质量5个指标进行因子探测。结果表明:(1)2015—2021年,阿勒泰市绿度和湿度指标对于区域内生态环境起显著正相关作用,温度、干度和空气质量这3个指标起显著负相关作用;(2)2015—2021年阿勒泰市MRSEI均值呈上升趋势,空间上,Ⅰ级和Ⅱ级生态指数区域的空间迁移能力较强,Ⅲ~Ⅴ级,即高生态指数区域在空间结构上相对较为稳定。Ⅰ~Ⅳ级生态指数重心总体向北移动,Ⅴ级生态指数重心整体向南移动,表明阿勒泰市南部高生态指数分布增长明显。(3)年份不同,造成生态环境质量改变的主导因子不同,阿勒泰市生态环境质量空间的演变是受到多个因素共同作用的结果。(4)MRSEI和RSEI(遥感生态指数)对阿勒泰市生态监测结果大致趋势一致,两者在空间分布和程度的差异与气溶胶光学厚度(AOD)的空间分布有关,表明了即使在空气质量较好的阿勒泰市AOD对其生态质量在空间分布上仍有影响。2015—2021年,阿勒泰市生态环境受多种因素影响有向南变好的趋势。 展开更多
关键词 改进型遥感生态指数 生态环境质量 地理探测器 重心迁移模型 阿勒泰市
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修理设备可更换的N-策略延迟不中断单重休假M/G/1可修排队系统分析
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作者 何亚兴 唐应辉 刘琼琳 《数学物理学报(A辑)》 CSCD 北大核心 2023年第2期625-645,共21页
该文考虑具有N-策略和延迟不中断单重休假的M/G/1可修排队系统,其中修理设备在修理故障服务台期间可发生故障且可更换.该文运用更新过程理论,全概率分解技术和拉普拉斯变换工具,讨论了服务台和修理设备的可靠性指标,比如服务台和修理设... 该文考虑具有N-策略和延迟不中断单重休假的M/G/1可修排队系统,其中修理设备在修理故障服务台期间可发生故障且可更换.该文运用更新过程理论,全概率分解技术和拉普拉斯变换工具,讨论了服务台和修理设备的可靠性指标,比如服务台和修理设备的瞬态不可用度,稳态故障频度以及在时间(0,t]内的平均故障次数等,并且对服务台的稳态不可用度和稳态故障频度进行了参数敏感性分析. 展开更多
关键词 m/G/1可修排队系统 N-策略 延迟不中断休假 可靠性指标 参数敏感性分析
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血清IgA、IgM、IgG联合肝功能指标检测应用于肝衰竭诊断中的临床价值
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作者 覃畯维 《中外医药研究》 2023年第15期146-148,共3页
目的:探讨血清免疫球蛋白A(IgA)、免疫球蛋白M(IgM)、免疫球蛋白G(IgG)联合肝功能指标检测应用于肝衰竭诊断中的临床价值。方法:选取2021年1月—2022年12月柳州市中医医院收治的250例肝衰竭患者为观察组,选取同期250例健康群体为对照组... 目的:探讨血清免疫球蛋白A(IgA)、免疫球蛋白M(IgM)、免疫球蛋白G(IgG)联合肝功能指标检测应用于肝衰竭诊断中的临床价值。方法:选取2021年1月—2022年12月柳州市中医医院收治的250例肝衰竭患者为观察组,选取同期250例健康群体为对照组。比较两组患者治疗前及观察组治疗前后的IgA、IgM、IgG水平及丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、谷氨酰基转移酶(GGT)水平。结果:治疗前,观察组IgA、IgM、IgG水平高于对照组,差异有统计学意义(P<0.001);治疗后,观察组IgA、IgM、IgG水平低于治疗前,差异有统计学意义(P<0.001)。治疗前,观察组ALT、AST、GGT水平高于对照组,差异有统计学意义(P<0.001);治疗后,观察组ALT、AST、GGT水平低于治疗前,差异有统计学意义(P<0.001)。结论:IgA、IgM、IgG联合肝功能指标基检测,能够对肝衰竭进行诊断。针对肝衰竭患者使用IgA、IgM、IgG联合肝功能指标检测方法能够明确病情,协助医生进行诊断,为后续制定诊疗计划提供有力依据,具有较高的临床应用价值。 展开更多
关键词 免疫球蛋白A 免疫球蛋白m 免疫球蛋白G 肝功能指标 肝衰竭
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一种提高跨语言理解的NLP迁移学习
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作者 王坤 盛鸿宇 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期153-163,共11页
随着互联网信息的发展,如何有效地表示不同语言所含的信息已成为自然语言处理(Natural Language Processing,NLP)领域的一项重要任务.然而,很多传统的机器学习模型依赖在高资源语言中进行训练,无法迁移到低资源语言中使用.为了解决这一... 随着互联网信息的发展,如何有效地表示不同语言所含的信息已成为自然语言处理(Natural Language Processing,NLP)领域的一项重要任务.然而,很多传统的机器学习模型依赖在高资源语言中进行训练,无法迁移到低资源语言中使用.为了解决这一问题,结合迁移学习和深度学习模型,提出一种多语言双向编码器表征量(Multi-lingual Bidirectional Encoder Representations from Transformers,M-BERT)的迁移学习方法.该方法利用M-BERT作为特征提取器,在源语言领域和目标语言领域之间进行特征转换,减小不同语言领域之间的差异,从而提高目标任务在不同领域之间的泛化能力.首先,在构建BERT模型的基础上,通过数据收集处理、训练设置、参数估计和模型训练等预训练操作完成M-BERT模型的构建,并在目标任务上进行微调.然后,利用迁移学习实现M-BERT模型在跨语言文本分析方面的应用.最后,在从英语到法语和德语的跨语言迁移实验中,证明了本文模型具有较高的性能质量和较小的计算量,并在联合训练方案中达到了96.2%的准确率.研究结果表明,该文模型实现了跨语言数据迁移,且验证了其在跨语言NLP领域的有效性和创新性. 展开更多
关键词 自然语言处理 多语言双向编码器表征量 迁移学习 跨语言 深度学习
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热水解对鸡粪和牛粪厌氧消化及重金属风险的影响 被引量:1
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作者 任征然 王佳伟 +5 位作者 高金华 文洋 韩军 李相昆 马培元 张含 《农业工程学报》 EI CAS CSCD 北大核心 2024年第4期254-261,共8页
为探究热水解预处理对鸡粪和牛粪在厌氧消化过程中产气效率的提升作用以及对消化残渣中重金属形态变化及潜在生态风险的影响。该研究以鸡粪和牛粪为处理对象,采用热水解处理技术,开展了连续中温厌氧消化试验。考察了热水解对畜禽粪污可... 为探究热水解预处理对鸡粪和牛粪在厌氧消化过程中产气效率的提升作用以及对消化残渣中重金属形态变化及潜在生态风险的影响。该研究以鸡粪和牛粪为处理对象,采用热水解处理技术,开展了连续中温厌氧消化试验。考察了热水解对畜禽粪污可生化性和重金属迁移风险。该研究还评估了连续施用厌氧消化鸡粪和牛粪15 a后土壤中重金属的积累量和Hakanson潜在生态风险指数。试验发现,鸡粪中木质纤维素含量占干固体总量的25%,牛粪为57.7%。热水解处理能够增强牛粪中木质纤维素的水解,热水解后木质纤维素的降解率为19.2%;但热水解对鸡粪的木质纤维素水解影响不明显,降解率仅为5.3%。鸡粪挥发性固体(volatile solid,VS)产气率为482 L/kg,热水解后产气率提升了12.4%;牛粪产气率为321 L/kg,热水解后产气率提升了31.2%。仅通过热水解不能降低鸡粪中重金属的迁移风险;而经过厌氧消化后,除Hg和Ni外,其他重金属迁移风险均降低到了低风险水平。牛粪经过热水解和厌氧消化处理后重金属向残渣态转换,但迁移风险没有明显改善。连续施用鸡粪和牛粪15 a后,土壤未出现的重金属积累,且15 a内总潜在生态风险等级处于低风险。该研究结果可为鸡粪和牛粪的能源化、无害化处理以及土地利用应用提供了理论依据和数据指导。 展开更多
关键词 积累 迁移风险 生物降解性 Hakanson潜在生态风险指数
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Mobile Agent选择移动迁移机制的设计与实现 被引量:8
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作者 蔡洪波 张大方 谢高岗 《计算机工程与科学》 CSCD 2001年第5期54-57,共4页
本文首先分析了当前 Mobile Agent系统面临的问题 ,提出了选择移动迁移机制的概念 ;然后对传统迁移机制和选择移动迁移机制对网络负载的影响进行了定量研究 ;最后 ,给出了一种采用选择移动迁移机制的 Mobile Agent系统模型 。
关键词 mOBILE AGENT 迁移机制 网络负载 计算机网络
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参杖颗粒含药血清对HSC增殖及α-SMA表达的抑制效应 被引量:4
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作者 段妍君 殷妮娜 +4 位作者 高清华 万莹 马维平 张昌文 吕文亮 《世界华人消化杂志》 CAS 北大核心 2014年第10期1396-1401,共6页
目的:研究参杖颗粒对α-平滑肌肌动蛋白(alpha smooth muscle actin,α-SMA)表达的影响,探讨该方影响肝星状细胞(hepatic stellate cell,HSC)迁移和增殖的调节机制.方法:将HSC分别培养于不同浓度的参杖颗粒含药血清中,采用Western blot... 目的:研究参杖颗粒对α-平滑肌肌动蛋白(alpha smooth muscle actin,α-SMA)表达的影响,探讨该方影响肝星状细胞(hepatic stellate cell,HSC)迁移和增殖的调节机制.方法:将HSC分别培养于不同浓度的参杖颗粒含药血清中,采用Western blot测定α-SMA的表达量;RT-PCR检测α-SMA mRNA表达量;流式细胞仪检测不同浓度的含药血清对HSC周期的影响;细胞划痕实验检测不同浓度的含药血清对HSC迁移的影响.结果:Western blot实验结果显示10倍浓度的参杖颗粒含药血清对HSC的α-SMA的表达有明显减少;同时RT-PCR结果显示α-SMA的mRNA水平在10倍浓度血清处理的HSC中最低;细胞周期检测结果显示细胞明显被阻滞于G2期,以10倍浓度组抑制增殖效果最明显;划痕实验显示10倍浓度血清处理的HSC迁移能力明显被抑制.结论:参杖颗粒对HSC的α-SMA的表达有明显抑制作用,并明显阻止HSC的迁移和增殖. 展开更多
关键词 肝星状细胞 Α-平滑肌肌动蛋白 参杖颗粒 增殖 迁移
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唐山老震区现今地震活动特征
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作者 周依 曹筠 +1 位作者 马旭东 单连君 《地震研究》 CSCD 北大核心 2024年第3期430-440,共11页
为分析唐山老震区地震活动背景,对该区域现今地震活动特征进行研究。老震区现今地震活动与1976年唐山M S7.8地震早期余震密集区域存在一定差异,结合区域背景地震活动统计结果,认为该区域地震活动受唐山地震序列影响逐渐减弱,逐步趋近于... 为分析唐山老震区地震活动背景,对该区域现今地震活动特征进行研究。老震区现今地震活动与1976年唐山M S7.8地震早期余震密集区域存在一定差异,结合区域背景地震活动统计结果,认为该区域地震活动受唐山地震序列影响逐渐减弱,逐步趋近于背景地震。地震分布呈现出明显的3分区差异,主要集中于中区,东区次之,西区最弱。中等地震的空间分布特征显示,地震活动存在东、中、西区交替发震的规律。目前,唐山老震区构造应力积累加速,存在地震活动水平由平静向活跃转变的可能,需要重点关注唐山断裂带北段以及滦县—乐亭断裂和卢龙断裂的交汇区域。 展开更多
关键词 唐山地震 地震活动特征 背景地震 迁移规律
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