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Early Cretaceous Archaefructus eoflora sp. nov. with Bisexual Flowers from Beipiao, Western Liaoning, China 被引量:23
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作者 JIQiang LIHongqi +2 位作者 L.MichelleBOWE LIUYusheng DavidWinshipTAYLOR 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第4期883-896,共14页
Recently, whether Archaefructus has bisexual multi-parted flowers or just inflorescences of unisexual flowers, and whether it is ancestral to all angiosperms or a derived eudicot have been debated. Here, from the same... Recently, whether Archaefructus has bisexual multi-parted flowers or just inflorescences of unisexual flowers, and whether it is ancestral to all angiosperms or a derived eudicot have been debated. Here, from the same Yixian Formation, NE China, we report a new Archaefructus species, A. eoflora sp. nov., with the generic characteristics of dissected leaves and bisexual reproductive axes. It is entirely preserved with roots, rhizome, shoots and protogynous reproductive organs at different developmental stages. Its lateral and main fertile shoots form a pseudo-indeterminate pattern, while the reproductive branches on the main shoot form a cymose inflorescence. Subtended by 1-2 bract-like leaves, the section of stamen clusters changes into a much shorter section of carpels that have one row of orthotropous ovules. Significantly, one cluster bearing two carpels and one stamen between the two sections demonstrates a true bisexual flower, an important step of the origin of floral bisexuality, and the homology between the stamen and carpel. The complex reproductive axes represent a mix between flowers and inflorescences, and suggest that A. eoflora sp. nov. possesses the potential to evolve into a variety of diverse flower types as found in modern basal and early fossil angiosperms. A comparison with other two species also leads to a revision of the generic diagnosis. 展开更多
关键词 Archaefructus eoflora bisexual flower fossil angiosperm orthotropous ovules plant evolution protogynous development Lower Cretaceous Yixian Formation
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THE ASYMPTOTIC PROPERTIES OF SUPERCRITICAL BISEXUAL GALTON-WATSON BRANCHING PROCESSES WITH IMMIGRATION OF MATING UNITS 被引量:1
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作者 马世霞 邢永胜 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期603-609,共7页
In this article the supercritical bisexual Galton-Watson branching processes with the immigration of mating units is considered. A necessary condition for the almost sure convergence, and a sufficient condition for th... In this article the supercritical bisexual Galton-Watson branching processes with the immigration of mating units is considered. A necessary condition for the almost sure convergence, and a sufficient condition for the L^1 convergence are given for the process with the suitably normed condition. 展开更多
关键词 bisexual Galton-Watson branching processes IMMIGRATION almost sure convergence L^1-convergence
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ON THE EXTINCTION OF POPULATION-SIZE-DEPENDENT BISEXUAL GALTON-WATSON PROCESSES 被引量:1
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作者 邢永胜 王学强 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期210-216,共7页
In this article, the population-size-dependent bisexual Galton-Watson processes are considered. Under some suitable conditions on the mating functions and the offspring distribution, existence of the limit of mean gro... In this article, the population-size-dependent bisexual Galton-Watson processes are considered. Under some suitable conditions on the mating functions and the offspring distribution, existence of the limit of mean growth rate per mating unit is proved. And based on the limit, a criterion to identify whether the process admits ultimate extinct with probability one is obtained. 展开更多
关键词 bisexual Galton-Watson branching processes population-size-dependent branching processes extinction probability
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The Stressors and Psychological Well-Being of Lesbian, Gay and Bisexual among Chinese Adults in Hong Kong
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作者 Lai Sheung Winnie Cheng 《Journal of Biosciences and Medicines》 2019年第5期65-70,共6页
Background: Lesbian, Gay and Bisexual (LGB) are individuals who often experienced stigma and discrimination which has detrimental effects on psychological well-being. Objectives: This study aimed to identify the major... Background: Lesbian, Gay and Bisexual (LGB) are individuals who often experienced stigma and discrimination which has detrimental effects on psychological well-being. Objectives: This study aimed to identify the major stressors and psychological well-being of LGB among Chinese adults in Hong Kong. Methods: A cross-sectional study was employed using self-administered questionnaires. Convenience sampling was used to recruit subjects. Demographic information, Measure of Gay-related stress (MOGS) and The Center for Epidemiologic Studies Depression Scale (CES-D Scale) were used to collect data. Results: The major stressor among LGB individuals in Hong Kong was family reaction. Majority of them had a high level of depression. Conclusion: LGB individuals in Hong Kong experienced high level of depression. 展开更多
关键词 LESBIAN GAY and bisexual DEPRESSION Sexual MINORITY MINORITY STRESS
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Anal Cancer in a HIV Sero-Positive Bisexual Bachelor—A Case Report and Literature Review
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作者 Victor Nwagbara M. E. Asuquo +1 位作者 J. A. Ashindoitiang S. O. Akpan 《Case Reports in Clinical Medicine》 2018年第12期601-607,共7页
Anal cancer, especially squamous cell carcinoma (SCC) variety, is evolving with rising incidence globally. This is due to the increasing adoption of risky life styles and social habits even in populations with rare oc... Anal cancer, especially squamous cell carcinoma (SCC) variety, is evolving with rising incidence globally. This is due to the increasing adoption of risky life styles and social habits even in populations with rare occurrences previously. This case report aims to expose risk factors exhibited by a patient recently managed for anal cancer in our facility before his demise. Early exposure to bisexual orientation, receptive anal intercourse and multiple sexual partners, are notable high risk factors for the development of anal SCC. The permissive role of smoking, illicit drug and alcohol use enhances the disease occurrence. Acquisition of human immune-deficiency virus (HIV) sero-positive status further reduces the body’s immune competence and enhances early age of onset as well as accelerates development of anal SCC. Proper history exploring the risk factors, physical/anorectal examination and histological analysis, are vital for proper diagnosis and staging which guides appropriate treatment with chemo-radiation as mainstay. 展开更多
关键词 ANAL Cancer bisexual Human Immune-Deficiency Virus Sero-Positive Status SQUAMOUS Cell Carcinoma
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A.S.Convergence Rate and L^(p)-Convergence of Bisexual Branching Processes in a Random Environment and Varying Environment
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作者 Sheng XIAO Xiang-dong LIU Ying-qiu LI 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2023年第2期337-353,共17页
Let(Z_(n))be a supercritical bisexual branching process in a random environmentξ.We study the almost sure(a.s.)convergence rate of the submartingale W_(n)=Z_(n)/In to its limit W,where(In)is an usually used norming s... Let(Z_(n))be a supercritical bisexual branching process in a random environmentξ.We study the almost sure(a.s.)convergence rate of the submartingale W_(n)=Z_(n)/In to its limit W,where(In)is an usually used norming sequence.We prove that under a moment condition of order p∈(1,2),W-W_(n)=o(e^(-na))a.s.for some a>0 that we find explicitly;assuming the logarithmic moment condition holds,we haveW-W_(n)=o(n^(-α))a.s..In order to obtain these results,we provide the L^(p)-convergence of(W_(n));similar conclusions hold for a bisexual branching process in a varying environment. 展开更多
关键词 bisexual branching process convergence rate varying environment random environment
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Bisexual Galton-Watson Branching Processes in Random Environments 被引量:29
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作者 Shi-xia Ma 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2006年第3期419-428,共10页
In this paper, we consider a bisexual Galton-Watson branching process whose offspring probability distribution is controlled by a random environment proccss. Some results for the probability generating functions assoc... In this paper, we consider a bisexual Galton-Watson branching process whose offspring probability distribution is controlled by a random environment proccss. Some results for the probability generating functions associated with the process are obtained and sufficient conditions for certain extinction and for non-certain extinction are established. 展开更多
关键词 bisexual Galton-Watson branching processes branching processes in random environments extinction probabilities
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An Undercover Angiosperm from the Jurassic of China 被引量:7
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作者 ZHENG Shaolin WANG Xin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第4期895-902,共8页
Searching for early angiosperms is a riveting activity in botany because it helps to resolve the phyiogenetic relationships among seed plants and among angiosperms themselves. One of the challenges for this job is wha... Searching for early angiosperms is a riveting activity in botany because it helps to resolve the phyiogenetic relationships among seed plants and among angiosperms themselves. One of the challenges for this job is what the target fossils look like. Most possibly early angiosperms may elude our scrutiny with gymnospermous appearances. This possibility becomes a reality in a Jurassic plant, Solaranthus gen. nov, which bears a peltaspermalean appearance and enclosed ovules. According to knowledge available hitherto, the latter feature makes it an angiosperm. However, such a feature is more likely to be eclipsed by its gymnospermous appearance. The early age and unexpected character assemblage of Solaranthus urge for a fresh look on the assumed-simple relationship between angiosperms and gymnosperms. Its resemblance to the order Peltaspermales favors the Mostly Male Theory. 展开更多
关键词 bisexual FLOWER JURASSIC ANGIOSPERMS Peltaspermales Mostly Male Theory
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FORM ERROR EVALUATION OF CIRCLES BASED ON A FINELY-DESIGNED GENETIC ALGORITHM 被引量:5
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作者 CuiChangcai CheRensheng LiZhongyan YeDong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第1期59-62,共4页
A genetic algorithm(GA)-based new method is designed to evaluate thecircularity error of mechanical parts. The method uses the capability of nonlinear optimization ofGA to search for the optimal solution of circularit... A genetic algorithm(GA)-based new method is designed to evaluate thecircularity error of mechanical parts. The method uses the capability of nonlinear optimization ofGA to search for the optimal solution of circularity error. The finely-designed GA (FDGA)characterized dynamical bisexual recombination and Gaussian mutation. The mathematical model of thenonlinear problem is given. The implementation details in FDGA are described such as the crossoveror recombination mechanism which utilized a bisexual reproduction scheme and the elitist reservationmethod; and the adaptive mutation which used the Gaussian probability distribution to determine thevalues of the offspring produced by mutation mechanism. The examples are provided to verify thedesigned FDGA. The computation results indicate that the FDGA works very well in the field of formerror evaluation such as circularity evaluation. 展开更多
关键词 Genetic algorithm(GA) Form error CIRCULARITY bisexual recombination Gaussian mutation
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Chemsex and its risk factors associated with human immunodeficiency virus among men who have sex with men in Hong Kong
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作者 Alex Siu Wing Chan Patrick Ming Kuen Tang Elsie Yan 《World Journal of Virology》 2022年第4期208-211,共4页
We were intrigued by Hanum et al,who published a study on the prevalence of human immunodeficiency virus(HIV)in homosexual,bisexual,and other men who have sex with men at sexual health clinics in England and the relat... We were intrigued by Hanum et al,who published a study on the prevalence of human immunodeficiency virus(HIV)in homosexual,bisexual,and other men who have sex with men at sexual health clinics in England and the relationship between baseline variables and future HIV occurrence.Chemically-enhanced sexual experience(chemsex)is becoming a global phenomenon.There are increasing medical and academic concerns about chemsex,where substances are used to boost sexual satisfaction,which is prevalent in groups,especially among homosexuals.Lesbians,gays,bisexuals,transgenders,and queers have become increasingly visible,valued,and committed community.However,chemsex requires urgent attention. 展开更多
关键词 Men who have sex with men METHAMPHETAMINE Application of novel psychoactive substances Drug abuse Lesbians gays bisexuals transgenders Chemsex
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The Earliest Normal Flower from Liaoning Province, China 被引量:4
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作者 Xin Wang Shaolin Zheng 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2009年第8期800-811,共12页
The early evolution of angiosperms has been a focus of intensive research for more than a century. The Yixian Formation in western Liaoning yields one of the earliest angiosperm macrofioras. Despite multitudes of angi... The early evolution of angiosperms has been a focus of intensive research for more than a century. The Yixian Formation in western Liaoning yields one of the earliest angiosperm macrofioras. Despite multitudes of angiosperm fossils uncovered, including Archaefructus and Sinocarpus, no bona fide normal flower has been dated to 125 Ma (mega-annum) or older. Here we report Callianthus dilae gen. et sp. nov. from the Yixian Formation (Early Cretaceous) in western Liaoning, China as the earliest normal flower known to date. The flower demonstrates a typical floral organization, including tepals, androecium, and gynoecium. The tepals are spatulate with parallel veins. The stamens have a slender filament, a globular anther, bristles at the anther apex, and in situ round-triangular pollen grains. The gynoecium is composed of two stylate carpels enclosed in a fleshy envelope, and develops into a "hip" when mature. Since the well-accepted history of angiosperms is not much longer than 125 Ma, Callianthus together with Chaoyangia, Archaefructus and Sinocarpus from the Yixian Formation demonstrate a surprisingly high diversity of angiosperms, implying a history of angiosperms much longer than currently accepted. 展开更多
关键词 ANGIOSPERM bisexual Callianthus Early Cretaceous FLOWER LIAONING PERIANTH Yixian Formation
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Health-related attitudes and risk factors for sexually transmitted infections of Chinese women who have sex with women 被引量:2
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作者 WANG Xiao-fang Jessie L. Norris +2 位作者 LIUYingjie Kathleen H. Reilly WANG Ning 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第16期2819-2825,共7页
Background Previous studies have shown evidence of health-related risk behaviors among women who have sex with women (WSW), such as sex with men, multiple bisexual partners, and drug use. Women who have sex with wom... Background Previous studies have shown evidence of health-related risk behaviors among women who have sex with women (WSW), such as sex with men, multiple bisexual partners, and drug use. Women who have sex with women have also been known to avoid routine physical examinations and conceal their same-sex history from physicians, which can affect their ability to receive an accurate diagnosis and treatment. No previous research has targeted women who have sex with women in China. We sought to describe women who have sex with women in China and explore risk factors for their reproductive tract infections (RTI)/sexually transmitted infections (STI). Methods Participants were recruited through outreach in venues and online for a cross-sectional study. Data were collected using interviews and laboratory tests. Results We recruited 224 women who have sex with women. In the year preceding their participation in the study, 92% (206/224) of women reported sexual relations with women. The RTI rates were: gonorrhea (15.8%), chlamydia (3.5%), syphilis (0.5%), bacterial vaginosis (14.4%), hepatitis B virus (HBV) (0.9%), hepatitis C virus (HCV) (0.5%), and candidiasis (6.9%). No HIV or herpes simplex virus (HSV) positive cases were detected. Factors associated with gonorrhea infection were non-Beijing local residency (odds ratio (OR)=2.1, 95% confidence interval (C/): 1.2-3.8) and genital-genital contact (OR=3.1, 95% CI: 1.3-7.2); factors associated with curable STI (excluding bacterial vaginosis, candidiasis, HBV and HCV) were non-Beijing local residency (OR=1.9; 95% CI: 1.2-3.0) and bleeding during or after sex (OR=18.1; 95% CI: 5.2-62.6); and the factor associated with RTI (including all the infections tested) was bleeding during or after sex (OR=37.8, 95% CI: 11.2-127.4). Conclusions Behaviors that may cause RTI/STI exist among Chinese women who have sex with women. Researchers should consider these behaviors when planninq correspondin.q prevention and interventions. 展开更多
关键词 women who have sex with women lesbian gay bisexual transgender HIV/AIDS sexual transmission sexually transmitted infection
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Dispersal patterns in Yunnan snub-nosed monkeys
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作者 Wancai XIA Fan WANG +5 位作者 Dali WANG Xiaoqin ZENG Chan YANG Ali KRZTON Baoping REN Dayong LI 《Current Zoology》 SCIE CAS CSCD 2022年第3期265-273,共9页
Sex-biased dispersal is common in group-living animals.Due to differences in local demographic and environmental factors,sex-biased dispersal presents many irregular patterns.In this study,a habituated,individually id... Sex-biased dispersal is common in group-living animals.Due to differences in local demographic and environmental factors,sex-biased dispersal presents many irregular patterns.In this study,a habituated,individually identified Yunnan snub-nosed monkey Rhinopithecus bieti group was observed over 9 years;192 dispersal events,including 97 male dispersal events(25 natal dispersal and 72 secondary dispersal)and 95 female dispersal events(34 natal dispersal and 61 secondary dispersal)were observed.Males and females showed different dispersal paths,dispersal ages,and dispersal patterns.Females had 2 dispersal paths,whereas males had 4 paths.In terms of age of dispersal,the male age of natal dispersal was younger than for females.Males prefer single dispersal,whereas females prefer parallel dispersal.Our study indicates that the dispersal pattern of R.bieti should be classified as a bisexual dispersal pattern.The differences in dispersal path,average age at dispersal,and dispersal path pattern indicate that Yunnan snub-nosed monkeys may still retain a loose matrilineal social system. 展开更多
关键词 bisexual dispersal dispersal parallel dispersal Rhinopithecus bieti
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UNCOVERING:THE ECONOMIC BENEFITS OF LGBT WORKPLACE INCLUSION
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作者 Darius Longarino 《Frontiers of Law in China-Selected Publications from Chinese Universities》 2019年第4期500-532,共33页
Lesbian,gay,bisexual,and transgender(LGBT)people constitute approximately five percent of the population,but workplace discrimination based on sexual orientation and gender identity remains troublingly commonplace.Thi... Lesbian,gay,bisexual,and transgender(LGBT)people constitute approximately five percent of the population,but workplace discrimination based on sexual orientation and gender identity remains troublingly commonplace.This article summarizes a large and growing body of social science research demonstrating the economic benefits of LGBT inclusion(and the costs of LGBT exclusion)in the workplace.It concludes with recommendations for(1)future research,stressing the need for more China-specific studies,which would inform policymaking and theoretical understanding of diversity and inclusion practices on business performance,(2)improving employer LGBT-inclusion policies,and(3)strengthening state protection of the equal employment rights of LGBT people. 展开更多
关键词 LESBIAN GAY bisexual and transgender(LGBT) business GENDER equal employment rights LGBT inclusion
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