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变温条件下解析Preisach磁滞模型误差修正和特征参数辨识方法

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电工电能新技术 2024年第6期43卷 60-69页

作者：陈彬曾庆麟王斐然万妮娜黄力唐波湖北省输电线路工程技术研究中心(三峡大学) 湖北宜昌443002 三峡大学电气与新能源学院湖北宜昌443002 国网湖北省电力有限公司宜昌供电公司湖北宜昌443002

温度升高会影响磁性材料的磁滞特性,从而改变电气设备的性能。目前解析Preisach模型无法对温度进行有效表征,导致损耗计算结果误差较大。为此,本文首先分析了基于Lorentzian函数的解析Preisach模型特征参数对磁滞回线形状参数的影响程度... 详细信息

温度升高会影响磁性材料的磁滞特性,从而改变电气设备的性能。目前解析Preisach模型无法对温度进行有效表征,导致损耗计算结果误差较大。为此,本文首先分析了基于Lorentzian函数的解析Preisach模型特征参数对磁滞回线形状参数的影响程度,如饱和磁通密度、矫顽力、剩磁等,研究了不同温度下模型参数和材料磁特性的变化。根据模型特征参数具有的磁滞回线形状相关性和温度相关性,引进温度系数来修正模型特征参数,构建变温条件下的解析Preisach模型,并给出了计及温度影响的模型参数辨识方法。最终实验测量纳米晶合金在变温条件下的极限磁滞回线,对多组实测值和修正后的解析Preisach模型计算值进行对比后,得出在饱和磁通密度、矫顽力和剩磁处修正模型结果的平均相对误差分别为0.15%、2.21%、5.76%,证明了该修正模型的准确性。

关键词：解析Preisach磁滞模型可逆磁化磁滞回线温度特性参数辨识

Shape change in viable eggs of the collembolan Folsomia candida provides insight into the role of Wolbachia endosymbionts

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Zoological Research 2010年第6期31卷 623-626页

作者： nina Hafer Nathan Pike Department of Zoology University of Oxford Tinbergen Building South Parks Road Oxford OX1 3PS UK

The endosymbiotic bacteria of the genus Wolbachia that infect the collembolan species Folsomia candida are responsible for facilitating parthenogenetic reproduction in their hosts. This study made empirical observations of the development of eggs of F. candida which contained normal populations of Wolbachia and of eggs which were cured of Wolbachia by treatment with the antibiotic rifampicin. A marked increase in egg size accompanied by a significant change in shape from spherical to discoid occurred in viable eggs three to four days after laying. These changes did not occur in the universally inviable eggs which came from the antibiotic treatment or in the 7% of untreated eggs which were naturally inviable. We infer that Wolbachia plays a critical role in zygotic or embryonic development during or before the first three days after laying and we draw on existing knowledge in speculating on the developmental mechanisms that Wolbachia may influence.

关键词： parthenogenesis embryonic development Collembola hatching rate

Mate-choice copying： Status quo and where to go

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Current Zoology 2015年第6期61卷 1073-1081页

作者： Klaudia WITTE nina KNIEL Ilka Maria KURECK Research Group of Ecology and Behavioral Biology Institute of Biology University of Siegen 57068 Siegen Germany

Mate-choice copying is a fascinating and widespread mate-choice strategy. Individuals gather public information about potential mates by observing others during sexual interactions and choose or reject the same individual as a mate as the observed individual did before. The influence of copying behavior on an individual＇s mate choice can be so strong that socially acquired information can override genetically based preferences for certain phenotypes. Thus, mate-choice copying enforces dy- namic processes in sexual selection. Here, we review the current state of research on mate-choice copying and focus on sex-specific aspects. We present evidence that mate-choice copying can support the evolution of novel sexual ornaments, and we discuss potential costs of mate-choice copying when public information is not reliable. Moreover, we discuss the conflict faced by males that copy since mate-choice copying increases sperm competition. In conclusion we suggest interesting topics for future research in mate-choice copying .

关键词： Mate-choice copying Public information Audience effect Sperm competition Novel ornaments

Host preference of the major strains of Plum pox virus--Opinions based on regional and world-wide sequence data

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Journal of Integrative Agriculture 2017年第3期16卷 510-515页

作者： nina Sihelská Miroslav Glasa Zdeno W Subr Biomedical Research Center Institute of Virology Slovak Academy of Sciences Bratislava 84505 Slovak Republic

Plum pox virus（PPV）causes sharka-the most serious viral disease of stone fruit *** is wide spread in Europe and Mediterranean Basin,its incidence has been further approved in Asia and both *** PPV strains have been recognized until now（PPV-D,PPV-M,PPV-Rec,PPV-EA,PPV-C,PPV-T,PPV-W,PPV-CR,and PPV-An）,forming molecularly distinct entities,however,only partially differentiable by their biological or epidemiological *** most strict virus-host linkages under natural conditions have been detected for strains naturally infecting cherries（PPV-C and PPV-CR）.However,although less stringent but still clear host preference is observed also for three epidemiologically most important strains（PPV-D/plum/apricot,PPV-M/peach,and PPV-Rec/plum）.So far no genetic marker has been mapped in the PPV genome,which responsibility for the host specificity/preference could be explicitly *** this review,we focus on the host preference of three major PPV strains as evidenced by analysis of an extensive dataset of PPV isolates of Slovak and world-wide ***,we discuss several performed relevant experiments and further possible research procedures aimed to better understand the genetic determinants and mechanisms of the host preference of this potyvirus.

关键词： sharka Prunus virus-host interactions

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一种新型重度铬污染土壤修复技术

科技创新与应用 2024年第13期14卷 30-34页

作者：蒋妮娜李东李林高然重庆远达烟气治理特许经营有限公司科技分公司重庆401122 重庆大学环境与生态学院重庆400044

我国退役铬化工企业的土壤铬污染严重,部分土壤六价铬浓度可高达10^(3)~10^(4)mg·kg^(-1),对植物生长、人类活动产生了不良影响。常用的铬污染土壤修复方法有还原修复技术、生物修复技术、酸淋洗-还原联合修复技术,用稀酸溶液加上还原... 详细信息

我国退役铬化工企业的土壤铬污染严重,部分土壤六价铬浓度可高达10^(3)~10^(4)mg·kg^(-1),对植物生长、人类活动产生了不良影响。常用的铬污染土壤修复方法有还原修复技术、生物修复技术、酸淋洗-还原联合修复技术,用稀酸溶液加上还原剂将土壤中的六价铬浸出、还原。但酸溶液对难提取六价铬的溶解效果有限,且易引起土壤侵蚀等次生环境问题。碱性条件下重度铬污染土壤淋洗和还原的修复工艺能有效解决酸淋洗存在的土壤溶蚀、钙流失、含盐量大幅增加以及其他重金属浸出浓度超标等次生环境问题,且该技术通过碱淋洗还原工艺显著提高难提取六价铬的提取和还原效率,该研究形成经济可行、易于推广的铬污染土壤修复技术路线。

关键词：污染土壤修复重度铬六价铬

Females choose gentle, but not healthy or macho males in Campbell dwarf hamsters （Phodopus campbelli Thomas 1905）

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Current Zoology 2017年第5期63卷 545-554页

作者： Konstantin A. ROGOVIN Anastasiya M. KHRUSHCHOVA Olga N. SHEKAROVA nina A. VASlLIEVA nina Yu VASILIEVA A.N. Severtsov Institute of Ecology and EvoLution RAS Leninskii prospect 33 Moscow 119071 Russia

Androgen-dependent male sexual traits （STs） as well as immunocompetence are theoreticallyassumed to be key indicators of a male＇s quality for the mate-choosing female. We studied matechoice by sexually motivated （SM） females of Campbell＇s dwarf hamsters. Females chose between2 tethered male siblings that differed in expression of STs. Males were unrelated to the female andable to contact and copulate with her. In both males, we measured sex-related morphology ofbody mass, mid-ventral specific skin gland, ano-genital distance, and external testicular *** also estimated levels of blood testosterone and cortisol, specific T- and B-cell immune re-sponses to antigens, as well as aggressive and sexual dominance in sibling males through add-itional encounter experiments with another SM female （male sibs could freely compete for thefemale）. We found that SM females chose a partner among 2 male sibs and spent over 80% of theirtime on average with the preferred male compared with the non-preferred one. Her choice was notassociated with the first visit of the chosen male, with a higher expression of sex-related traits,higher levels of blood testosterone, or with aggressive dominance. The choice was not associatedwith the intensity of T-cell immune response to phitohemagglutinin （PHA）. Instead there was a ten-dency for a negative relationship with the expression of STs and B-cell response to the antigenchallenge. The only character that unambiguously influenced female choice was the non-aggressive male to female grooming during sexual contact. There was no difference in breedingsuccess between preferred and non-preferred males paired with virgin females.

关键词： Campbell's dwarf hamsters, female mate choice, immunocompetence handicap, male-male aggression, sexual traits,testosterone.

Multiplex Rapid Test with Acceptable Diagnosis Performance as a Solution to Increase Diagnosis of Hepatitis B and C Viruses in Pregnant Women in an Area of High Prevalence of Both Hepatitis Viruses Associated with HIV

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Open Journal of Medical Microbiology 2024年第1期14卷 50-65页

作者： Catherine Boni-Cisse nina Esther Onstira Ngoyi Hermione Dahlia Mossoro-Kpinde Noella Packo Rabi Senekian Hermann Ndoidet Koutou Coretha Bokia-Baguida Christelle Luce Bobossi-Gadia Arthur Simplice Sombot-Ndicky Daniel Yvon Gonessa Freddy Samuel Ngbonga Konzapa Voulou Christian Diamant Mossoro-Kpinde Alassane OUATTARA National Center of Medical Oncology and Radiotherapy Abidjan Ivory Cost Department of Microbiology UFR of Medical Sciences University of Cocody Abidjan Ivory Cost Laboratory of Bacteriology-Virology of Teaching Hospital Center of Brazzaville Brazzaville Republic of Congo Faculty of Health Sciences Marien NGOUABI University Brazzaville Republic of Congo Department of Labor Medicine Service of HIV and STDs Control in the Workplace Bangui Central African Republic (CAR) Faculty of Health Sciences University of Bangui Bangui Central African Republic National Reference Center of Sexually Transmitted Diseases and Antiretroviral Therapy Bangui Central African Republic National Laboratory of Clinical Biology and Public Health Bangui Central African Republic Medicine Department District Hospital of Alindao Alindao Ouaka Prefecture Central African Republic Doctoral School of Sciences and Technology University of Bangui Bangui Central African Republic Coordination of Specialized Study of Clinical Biology University of Bangui Bangui Central African Republic Doctors without Borders Hospital Sica BanguiCRA Laboratory of Medical Analysis of Teaching Hospital Center Mother Elisabeth DOMITIEN of Bimbo Bimbo Central African Republic

Background and Objective: HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) are very widespread in the world, however, less than 20% of the people affected are diagnosed and treated. This study aimed to determine the prevalence of HIV, HCV and HBV co-infections in pregnant women at Bangui Community University Hospital and the cost of screening. Methods: A cross-sectional study involving consenting pregnant women who came for antenatal care was performed. HIV, HCV antibodies and HBV antigens were detected using Exacto Triplex? HIV/HCV/HBsAg rapid test, cross-validated by ELISA tests. Sociodemographic and professional data, the modes of transmission and prevention of HIV and both hepatitis viruses were collected in a standard sheet and analyzed using the Epi-Info software version 7. Results: Pregnant women aged 15 to 24 were the most affected (45.3%);high school girls (46.0%), and pregnant women living in cohabitation (65.3%) were the most represented. Twenty-five (16.7%) worked in the formal sector, 12.7% were unemployed housewives and the remainder in the informal sector. The prevalence of HIV, HBV, and HCV viruses was 11.8%, 21.9% and 22.2%, respectively. The prevalence of co-infections was 8.6% for HIV-HBV, 10.2% for HIV-HCV, 14.7% for HBV-HCV and 6.5% for HIV-HBV-HCV. All positive results and 10% of negative results by the rapid test were confirmed by ELISA tests. The serology of the three viruses costs 39,000 FCFA (60 Euros) by ELISA compared to 10,000 FCFA (15.00 Euros) with Exacto Triplex? HIV/HCV/AgHBs (BioSynex, Strasbourg, France). Conclusion: The low level of education and awareness of hepatitis are barriers to development and indicate the importance of improving the literacy rate of women in the Central African Republic (CAR). Likewise, the high prevalence of the three viruses shows the need for the urgent establishment of a national program to combat viral hepatitis in the CAR.

关键词： HIV-HCV-HBV Co-Infection Multiplex Immunochromatographic Rapid Test Central Africa Serology Test Cost Diagnostic Accessibility

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硅改性酚醛树脂物理性能的分子动力学模拟

计算物理 2024年第3期41卷 345-356页

作者：许铋立景昭刘骁代波姬广富张魁宝葛妮娜西南科技大学环境友好能源材料国家重点实验室四川绵阳621010 北京航天长征飞行器研究所北京100076 中国空气动力研究与发展中心四川绵阳621000 中国工程物理研究院流体物理研究所四川绵阳621900

采用分子动力学模拟方法研究纳米SiO2以及甲基苯基二甲氧基硅烷改性酚醛树脂的物理性能。研究表明:300 K下未改性酚醛树脂玻璃转化温度为362 K,弹性模量、剪切模量分别为5.45 GPa和2.19 GPa,热导率和热膨胀系数分别为0.37 W·(m·k)-1和... 详细信息

采用分子动力学模拟方法研究纳米SiO2以及甲基苯基二甲氧基硅烷改性酚醛树脂的物理性能。研究表明:300 K下未改性酚醛树脂玻璃转化温度为362 K,弹性模量、剪切模量分别为5.45 GPa和2.19 GPa,热导率和热膨胀系数分别为0.37 W·(m·k)-1和3.8×10-5 K-1,添加纳米SiO2后玻璃转化温度提高了1.6%,弹性模量、剪切模量分别提高了34.9%和28.8%,热导率和热膨胀率分别降低了11%和31.6%。SiO2表面接枝3%、5%、7%和10%硅烷偶联剂以及甲基苯基二甲氧基硅烷改性酚醛树脂玻璃转化温度分别提高了10.5%、15.2%、16.8%、19.3%和1.5%,弹性模量分别提高了44.4%、53.2%、53.8%、63.5%和13.4%,而热导率分别降低了12.4%、13.5%、11.2%、7%和10%。此外甲基苯基二甲氧基硅烷改性的酚醛树脂的热膨胀系数较未改性酚醛树脂提高15.7%。研究表明:掺杂纳米SiO2、SiO2表面接枝硅烷偶联剂以及甲基苯基二甲氧基硅烷改性都能够提高酚醛树脂的玻璃转化温度,机械性能同时降低热导率,而对于热膨胀系数,纳米SiO2掺杂使其减小,甲基苯基二甲氧基硅烷改性则会使其明显增大。

关键词：硅改性酚醛树脂玻璃转化温度热导率力学性能分子动力学模拟

An Integrated Causal Path Identification Method

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Wuhan University Journal of Natural Sciences 2019年第4期24卷 305-313页

作者： FEI nina YANG Youlong School of Mathematics and Statistics Xidian University

Finding causality merely from observed data is a fundamental problem in science. The most basic form of this causal problem is to determine whether X leads to Y or Y leads to X in the case of joint observation of two variables X, Y. In statistics, path analysis is used to describe the direct dependence between a set of variables. But in fact, we usually do not know the causal order between variables. However, ignoring the direction of the causal path will prevent researchers from analyzing or using causal models. In this study, we propose a method for estimating causality based on observed data. First, observed variables are cleaned and valid variables are retained. Then, a direct linear non-Gaussian acyclic graph models(DirectLiNGAM) estimates the causal order K between variables. The third step is to estimate the adjacency matrix B of the causal relationship based on K. Next, since B is not convenient for model interpretation, we use adaptive lasso to prune the causal path and variables. Further, a causal path graph and a recursive model are established. Finally, we test and debug the recursive model, obtain a causal model with good fit, and estimate the direct, indirect and total effects between causal variables. This paper overcomes the randomness assigning causal order to variables. This study is different from the researcher’s understanding of his own model by generating some form of simulation data. The simplest and relatively unsmooth statistical learning method used in this study has obvious advantages in the field of interpretable machine learning.

关键词： observed variable path analysis causal order Direct LiNGAM causal path graph causal effect