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Contributions of Trimorphic Life Cycles to Dispersal and Evolutionary Trends in Large Benthic Foraminifers

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Journal of Earth Science 2022年第6期33卷 1425-1433页

作者： Pamela hallock Claire E.Reymond College of Marine Science University of South FloridaSt.PetersburgFL33701USA School of Earth Sciences China University of GeosciencesWuhan430074China School of Geosciences The University of SydneySydneyNSW2006Australia

The basic life cycle of Foraminifera has long been recognized as alternation between sexual and asexual generations;a common modification is several successive asexual generations.Production and release of flagellated gametes also has been documented as the basic sexual-reproductive mode in extant lineages.Research on population dynamics,local spatial distributions,and biogeography of Amphistegina spp.and Heterostegina depressa have been augmented by culture studies over the past 50years,providing insights that have been widely used in paleoecological and paleoenvironmental interpretations.Hypotheses are proposed suggesting how stages in the life cycle might contribute to understanding biogeographic and evolutionary trends commonly observed in large benthic foraminifers.Recruitment of sexually-produced cryptobiotic propagules,followed by successive asexual generations(schizogeny),can potentially establish viable,locally-adapted populations within literally years,consistent with the concepts of both allopatric speciation and reticulate evolution associated with isolation and reconnection of local basins.The review concludes with the recommendation that future studies utilizing genomics,proteonomics,geochemistries,scanning technologies,and other approaches can promote greater understanding of both modern and fossil larger benthic foraminiferal lineages.

关键词： Amphistegina coiling ratio diatom symbionts Heterostegina depressa propagule schizogeny life cycle

Preface for“Tropical Large Benthic Foraminifera:Adaption,Extinction,and Radiation”

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Journal of Earth Science 2022年第6期33卷 1339-1347页

作者： Claire E.Reymond Pamela hallock Hildegard Westphal School of Earth Sciences China University of GeosciencesWuhan430074China School of Geosciences The University of SydneySydneyNSW2006Australia College of Marine Science University of South FloridaSt.PetersburgFL33701USA Leibniz-Centre for Tropical Marine Research(ZMT) BremenGermany Department of Geosciences Bremen UniversityBremenGermany King Abdullah University of Science and Technology(KAUST) ThuwalSaudi Arabia

The purpose of this special issue is to bring together recent advances in the field of research on LBF(Large Benthic Foraminifera)for those working on the topic and also to the broader bio-geological community.Here we give a brief overview on the development of the term LBF,state of knowledge on key moments in evolutionary history,current systematics.

关键词： evolutionary Large knowledge

Tropical Large Benthic Foraminifera: Adaption， Extinction， and Radiation

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Journal of Earth Science 2021年

作者： Claire E.Reymond Pamela hallock Hildegard Westphal Chinese University of Geoscience Wuhan College of Marine Science， University of South Florida University of Bremen King Abdullah University of Science and Technology

PREFACE The purpose of this special issue is to bring together recent advances in the field of research on Large Benthic Foraminifera (LBF) for those working on the topic and also to the broader bio-geological community. Here we give a brief overview on the development of the term LBF， state of knowledge on key moments in evolutionary history， current systematics， paleoecological， stratigraphic， and modern applications， and sketch possible future directions of LBF research. Perhaps our view is biased， but in our perception， LBF research is maturing into a rich multidisciplinary discussion. The field has a strong geological foundation， yet there are still so many unknowns in the past， present and future of LBF， and a lot of room for scientific breakthroughs in particular when integrating biological approaches. We enjoyed putting this issue together and hope it is a springboard for future ideas.

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Demonstration of no catalytical activity of Fe-N-C and Nb-N-C electrocatalysts toward nitrogen reduction using in-line quantification

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SusMat 2022年第4期2卷 476-486页

作者： Arnar Sveinbjörnsson Anna Bergljót Gunnarsdóttir Erin B.Creel Camila Pía Canales Barr Zulevi Xiang Lyu Charl J.Jafta Egill Skúlason Alexey Serov Helga Dögg Flosadóttir Atmonia ehf. ReykjavíkIceland Faculty of Industrial Engineering Mechanical Engineering and Computer ScienceUniversity of IcelandVR-IIIReykjavíkIceland Electrification and Energy Infrastructures Division Oak Ridge National LaboratoryOak RidgeTennesseeUSA Pajarito Powder LLC(PPC)AlbuquerqueNew MexicoUSA Science Institute University of IcelandVR-IIIReykjavíkIceland

Ammonia(NH3)production via the electrochemical nitrogen reduction reaction(NRR)is a promising method for sustainable generation of this important chemical.Efforts are ongoing in finding an efficient,stable,and selective catalyst that will enable the reaction.However,progress is hindered in the field due to lack of reproducibility,most likely a consequence of reports of false-positive results due to improper measurement control and methods.In this study,we explore the NRR activity of a promising class of single atom catalysts,transition metal-nitrogen-carbon(M-N-C)electrocatalysts.Using a state-of-the-art in-line ammonia quantification methodology,with detection limit as low as 1 ppb for ammonia,we show that single atom Nb and Fe embedded in a stable carbon and nitrogen framework do not electrochemically reduce N_(2) to NH_(3).Critically,this demonstrates that our experimental setup with in-line sequential injection analysis successfully excludes ammonia contamination from the gas supply and atmospheric sources,allowing for thorough and high-throughput examination of potential NRR catalysts.

关键词： ammonia synthesis electrocatalysis nitrogen electroreduction NRR single atom catalyst

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关百益与河南大学关系考论

河南大学学报（社会科学版） 2022年第5期62卷 1-5,152页

作者：葛本成河南大学文学院河南开封475001

关百益是20世纪30年代著名的考古学家、书法家,在史学、金石学、甲骨学、方志、书画等领域造诣较深,曾先后两次在河南大学工作:20世纪20年代中期,关百益受聘中州大学,任博物兼国文教员;30年代中期,以特设纂修身份加入附设于省立河南大... 详细信息

关百益是20世纪30年代著名的考古学家、书法家,在史学、金石学、甲骨学、方志、书画等领域造诣较深,曾先后两次在河南大学工作:20世纪20年代中期,关百益受聘中州大学,任博物兼国文教员;30年代中期,以特设纂修身份加入附设于省立河南大学的河南省通志馆,其间他还受托为河南大学新建校门题写校训,这是河南大学一段鲜为人知的珍贵校史。

关键词：关百益河南大学关系

Running Head： Foram Assemblages from Three Substrata Comparison of Foraminiferal Assemblages from Three Kinds of Substrata, Durney Key, West-Central Florida, USA

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Journal of Environmental Science and Engineering 2011年第9期5卷 1239-1244页

作者： K. Anderson P. hallock Department of Science American Samoa Community College Pago Pago 96799 USA College of Marine Science University of South Florida St. Petersburg 3370 USA

As part of a project that assessed a proposed artificial reef site, this study compared benthic foraminiferal assemblages from three substrata: sediment, natural lime rock and recruitment tiles. The assemblage from sediment samples included 21 foraminiferal species representing 12 genera and was dominated by stress-tolerant taxa, especially Ammonia and Elphidium. Natural lime rock and recruitment tiles yielded 21 foraminiferal species representing 11 genera, which were dominated by miliolids. Intersample variability was characterized by "pulsating patches" as has been previously described for Florida estuaries. The predominance of stress-tolerant taxa in sediments was consistent with other observations from the site, which indicated that proposed artificial reef structures were not likely to recruit significant coral-reef biota.

关键词：美国佛罗里达州底栖有孔虫中西部运行人工鱼礁人工渔礁石灰岩沉积物

Herbst矫治器伴头帽牵引治疗安氏Ⅱ类错

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华西口腔医学杂志 2004年第1期22卷 46-48,51页

作者：杜熹 Urban Hgg 四川大学华西口腔医院正畸科四川成都610041 香港大学牙学院正畸专业

目的　研究Herbst矫治器伴头帽牵引逐步前伸下颌对安氏Ⅱ类错的矫治效果。方法　治疗组 2 2例患者 ,对照组 31例患者。治疗组患者均按治疗的前 6个月、后 6个月 (平均 )及维持期 6个月 ,3个阶段治疗并拍摄头侧位定位片观察。对照组患... 详细信息

目的　研究Herbst矫治器伴头帽牵引逐步前伸下颌对安氏Ⅱ类错的矫治效果。方法　治疗组 2 2例患者 ,对照组 31例患者。治疗组患者均按治疗的前 6个月、后 6个月 (平均 )及维持期 6个月 ,3个阶段治疗并拍摄头侧位定位片观察。对照组患者拍摄 2次头侧位定位片 ,其间间隔 6个月。结果　平均治疗 12个月后的疗效是抑制上颌骨生长、刺激下颌骨生长并降低下面高。与对照组相比 ,对上颌骨的抑制作用在治疗的前后 6个月均有统计学意义 ,对下颌骨的刺激作用仅在治疗前 6个月有统计学意义 ,对下面高的降低作用仅在治疗后 6个月有统计学意义。维持阶段上下基骨关系不变而对下面高的降低作用进一步加强。结论　Herbst矫治器伴头帽牵引能有效地矫治安氏Ⅱ类错 ,对上颌骨的作用随时间的增加而加强。

关键词： Herbst矫治器头帽牵引治疗安氏Ⅱ类错He 上颌骨

智联招聘CEO郭盛:丰裕时代已来,让Z世代定义“好雇主”

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商学院 2022年第1期 49-50页

作者： gg

2021年12月18日,“‘HI,液态职场’2021中国年度最佳雇主颁奖盛典”以线上直播方式盛大启幕。本次盛典由智联招聘主办,北京大学社会调查研究中心、北京大学国家发展研究院、中国劳动经济学会、世界卫生组织、《哈佛商业评论》、HR公会... 详细信息

2021年12月18日,“‘HI,液态职场’2021中国年度最佳雇主颁奖盛典”以线上直播方式盛大启幕。本次盛典由智联招聘主办,北京大学社会调查研究中心、北京大学国家发展研究院、中国劳动经济学会、世界卫生组织、《哈佛商业评论》、HR公会等多家专业机构参与组织、评审,北京大学国家发展研究院院长姚洋,北京大学国家发展研究院BiMBA商学院院长、北京大学王宽诚讲席教授陈春花,中国上市公司协会会长宋志平担任本届评委会主席。

关键词：劳动经济学中国上市公司评委会主席社会调查研究直播方式陈春花最佳雇主王宽诚

Diffraction property of photorefractive volume grating in Ce: KNSBN for ordinarily polarized reading beam

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Chinese Science Bulletin 2000年第2期45卷 145-149页

作者： Liang, BL Wang, ZQ Mu, gg Guan, JH Fu, RL Nankai Univ Optoelect Informat Sci & Technol Lab Inst Modern Opt Tianjin 300071 Peoples R China

The diffraction efficiency of volume grating written by two wave mixing in Ce:KNSBN photorefractive crystal versus the writing beam ratio for ordinarily polarized reading beam is experimentally studied. The result is different from that for the extraordinarily polarized reading beam. Then the modified coupled-wave theory is used to fit the experimental data. The theoretical results are coincident with the experimental data quite well. This research gives a significant Support to the applications of Ce:KNSBN crystal in holographic recording and optical information processing.

关键词： photofractive grating diffraction efficiency energy transfer.