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Chinese Journal Of Geochemistry 2012年第1期31卷 48-54页

作者： Ekere E.Ukwang Barth N.Ekwueme alfred.Krner Department of Geology University of CalabarEtta AgborP.M.B.1115 CalabarNigeria Institut fur Geowissenschaften Universitat MainzGermany

The Ukwortung area of the Obudu Plateau exposes high-grade metamorphic rocks of upper amphibolite to granulite facies. Zircon grains from three locations of Southwest Obudu Plateau were dated by the Pb-Pb dating method. This single zircon radiometric dating method confirms the occurrence of Mesoproterozoic crust in the southeastern Nigeria basement complex. The pyroxene gneiss (granulite facies) sample from Biereberi near Ukpe yielded a mean age of 2061.4±0.4 Ma, suggesting the presence of Paleoproterozoic crust. The combined 207Pb/206Pb ratios from the garnet-biotite gneiss in the area gave a mean age of 1794.4±0.4 Ma. This further confirms the pres-ence of Paleoproterozoic crustal components within the Obudu Plateau. The Mesoproterozoic (1548.8±0.5 Ma) and Neoproterozoic (619.8±0.9 Ma) ages were obtained from two populations of zircon grains from the leucogranite in Okordem, Southwest Obudu. These "signatures" collaborate the occurrence of Mesoproterozoic ages in the Afar region and Cameroon basements along with the southeastern Nigerian basement complex, constituting the major portion of the West Central African mobile belt. The zircon age of 1794.4±0.4 Ma may probably be the maximum depositional age of the meta-sediment (garnet-biotite gneiss) and the age of 1548.8±0.5 Ma may be interpreted as the time of emplacement of the granitoid. The Neoproterozoic age (619.8±0.9 Ma) probably records the metamorphic event that was prevalent during the Pan-African period and thus affected the area.

关键词：单颗粒锆石平均年龄地壳成分中元古代尼日利亚地下室东南部证据

Civil and structural engineering applications,recent trends,research and developments on pultruded fiber reinforced polymer closed sections:a review

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Frontiers of Structural and Civil Engineering 2013年第3期7卷 227-244页

作者： alfred.Kofi GAND Tak-Ming CHAN James Toby MOTTRAM Civil Research Group School of EngineeringUniversity of WarwickCoventry CV47ALUnited Kingdom

The objectives of this study are to review and evaluate the developments and applications of pultruded fiber-reinforced polymer composites in civil and structural engineering and review advances in research and *** case applications are *** paper presents a state-of-the-art review of fundamental research on the behavior of pultruded fiber reinforced polymer closed sections and highlights gaps in knowledge and areas of potential further research.

关键词： fibre reinforced polymer composites behaviour of FRPs tubular sections pultruded FRP tubular profiles FRP tubes in bridges applications of pultruded FRP tubes new-build with FRP tubes

Chemically Induced and Light-Independent Cryptochrome Photoreceptor Activation

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Molecular Plant 2008年第1期1卷 4-14页

作者： Gesa Rosenfeldt Rafael Munoz Viana Henning D. Mootz Albrecht G. von Arnim alfred.Batschauera FB Biologie-pflanzenphysiologie Philipps-Universitat Karl-von-Frisch-Str. 8 35032 Marburg Germany Universitat Dortmund FB Chemie-Chemische Biologie Otto-Hahn-Str. 6 44227 Dortmund Germany University of Tennessee Department of Biochemistry Cellular and Molecular Biology Waiters Life Sciences M407 Knoxville TN 37996-0840 USA

The cryptochrome photoreceptors of higher plants are dimeric proteins. Their N-terminal photosensory domain mediates dimerization, and the unique C-terminal extension （CCT） mediates signaling. We made use of the human FK506binding protein （FKBP） that binds with high affinity to rapamycin or rapamycin analogs （rapalogs）. The FKBP-rapamycin complex is recognized by another protein, FRB, thus allowing rapamycin-induced dimerization of two target proteins. Here we demonstrate by bioluminescence resonance energy transfer （BRET） assays the applicability of this regulated dimer- ization system to plants. Furthermore, we show that fusion proteins consisting of the C-terminal domain of Arabidopsis cryptochrome 2 fused to FKBP and FRB and coexpressed in Arabidopsis cells specifically induce the expression of cryptochrome-controlled reporter and endogenous genes in darkness upon incubation with the rapalog. These results demonstrate that the activation of cryptochrome signal transduction can be chemically induced in a dose-dependent fashion and uncoupled from the light signal, and provide the groundwork for gain-of-function experiments to study specifically the role of photoreceptors in darkness or in signaling cross-talk even under light conditions that activate members of all photoreceptor families.

关键词： C-terminal extension (CCT) FK506-binding protein (FKBP) bioluminescence resonance energy transfer (BRET)

Carboniferous Alaskan-type complex along the Sino–Mongolian boundary,southern margin of the Central Asian Orogenic Belt

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Acta Geochimica 2017年第2期36卷 276-290页

作者： Yuruo Shi Linlin Li alfred.Kroner Jing Ding Wei Zhang Zengbao Huang Ping Jian Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institut für Geowissenschaften Universitat Mainz 55099 Mainz Germany Geological Survey of Gansu Province Lanzhou 735000 China

We present zircon ages and geochemical data for the Hongshishan Carboniferous Alaskan-type mafic–ultramafic complex exposed in the Beishan area along the Sino–Mongolian boundary, southern margin of the Central Asian Orogenic Belt. This complex mainly consists of dunite,harzburgite, lherzolite, wehrlite, and gabbro, which intrudes Early Carboniferous volcanic rocks and reveals a zoned structure. Zircons of a gabbro sample yielded a 206Pb/238 U age of 357 ± 4 Ma, reflecting the time of Early Carboniferous magmatism. Zircon ages were also obtained for an andesite(322 ± 3 Ma) and a basaltic andesite(304 ± 2 Ma).High initial Nd isotope whole-rock values suggest that the Hongshishan gabbro [e_(Nd(t))= +9.6-+10.2] and basalt[eNd(t)= +10.0-+10.8] were derived from a depleted mantle source. Slightly lower eNd(t)values for the ultramafic rocks [eNd(t)= +8.5-+8.7] suggest some interaction of the parental magma with the continental crust. In contrast, the Late Carboniferous Quershan samples in this area represent subduction-related arc volcanic rocks with Adakite-like compositions. The early Carboniferous Hongshishan Alaskan-type complex was interpreted to represent the remnants of a magma chamber that crystallized at the base of a mature island arc, whereas the Quershan island arc volcanic rockssuggest the resurrection of the subduction process after arccontinent collision and uplift of the roots of the arc.

关键词： Alaskan-type complex Carboniferous Zircon age Sino-Mongolian boundary CAOB

Geochemistry and SHRIMP U-Pb Zircon Dating of Mafic Rocks North of Zunhua City, Eastern Hebei, North China Craton： Paleoproterozoic Gabbro rather than Neoarchean Ophiolite

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1024-1040页

作者： XIE Hangqiang DONG Chunyan alfred.KRONER LIU Shoujie BAI Wenqian LIU Dunyi WAN Yusheng Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beo'ing 10003 7 China Department of Geosciences University of Mainz D-55099 Mainz Germany

Abundant mafic-ultramafic blocks and dikes occur in the area north of Zunhua City, eastern Hebei Province, and were previously suggested to be part of a late Archean ophiolitic assemblage. We employed SHRIMP zircon dating and a geochemical study on these mafic and surrounding rocks to test the ophiolite hypothesis. The SHRIMP data suggest that three metagabbro samples were metamorphosed at ～1.8 Ga. Numerous ～2.5 Ga zircons display strong oscillatory zoning, characteristic of zircons from granitoid rocks but not from gabbro, so we suggest that these are xenocrystic grains. The age of these xenocrystic zircons and their metamorpbic rims suggests that these mafic blocks formed in Paleoproterozoic. The surrounding gneiss of intermediate composition also contains 2.5 Ga zircons with oscillatory zoning and 1.8 Ga metamorphic rims. Fractionated REE patterns and Nb, Ta, Zr, Hf negative anomalies to variable extent were observed in the mafic blocks and surrounding rocks, also supporting a significant difference in the chemistry of ophiolitic rocks. Our data suggest that many mafic blocks in northern Zunhua are not part of a late Archean ophiolite complex but part of a tectonically dismembered Paleoproterozoic intrusive gabbro complex. This study shows that late Paleoproterozoic metamorphism occurred in the western part of eastern Hebei Province.

关键词： metagabbro ophiolite SHRIMP zircon dating Zunhua North China Craton

Laparoscopic surgery for benign and malign diseases of the digestive system:Indications,limitations,and evidence

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World Journal of Gastroenterology 2014年第17期20卷 4883-4891页

作者： Markus Alexander Küper Friederike Eisner alfred.K?nigsrainer J?rg Glatzle Department for General and Visceral Surgery Bundeswehr Hospital BerlinD-10115 BerlinGermany Department for General Visceral and Transplant SurgeryUniversity Hospital Tübingen72076 TübingenGermany

The laparoscopic technique was introduced in gastrointestinal surgery in the mid 1980s. Since then, the development of this technique has been extraordinary. Triggered by technical innovations (stapling devices or coagulation/dissecting devices), nowadays any type of gastrointestinal resection has been successfully performed laparoscopically and can be performed laparoscopically dependent on the patient’s condition. This summary gives an overview over 30 years of laparoscopic surgery with focus on today’s indications and evidence. Main indications remain the more common procedures, e.g., appendectomy, cholecystectomy, bariatric procedures or colorectal resections. For all these indications, the laparoscopic approach has become the gold standard with less perioperative morbidity. Regarding oncological outcome there have been several high-quality randomized controlled trials which demonstrated equivalency between laparoscopic and open colorectal resections. Less common procedures like esophagectomy, oncological gastrectomy, liver and pancreatic resections can be performed successfully as well by an experienced surgeon. However, the evidence for these special indications is poor and a general recommendation cannot be given. In conclusion, laparoscopic surgery has revolutionized the field of gastrointestinal surgery by reducing perioperative morbidity without disregarding surgical principles especially in oncological surgery.

关键词： Laparoscopy Gastrointestinal surgery Esophagus Stomach Cholecystectomy Colorectal surgery Liver resection Pancreas resection Laparoscopic resection of gastrointestinal

Advanced therapy of overweight or obese polycystic ovary syndrome:a prospective study

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Global Health Journal 2022年第2期6卷 75-79页

作者： Min Min Xiangyan Ruan alfred.O.Mueck Department of Gynecological Endocrinology Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijing Maternal and Child Health Care Hospital Yaojiayuan Road 251Beijing 100026China Department of Womens Health University Hospital TuebingenCalwer Strasse 7Tuebingen 72076Germany

Objective:To investigate the effects of orlistat combined with drospirenone/ethinylestradiol tablets(DRSP/EE)on anthropometric indices,sexual hormones,hepatorenal function parameters of overweight or obese patients with polycystic ovary syndrome(PCOS).Methods:75 overweight or obese PCOS patients[body mass index(BMI)>24 kg/m^(2)]were recruited within the Department of Gynecological Endocrinology,Beying Obstetrics and Gynecology Hospital,Capital Medical University,from April 2019 to January 2020,for a prospective,randomized,open-labelled comparing *** were numbered one by one according to the order of recruitement and randomly divided into two groups,group 1 included 50 patients,orlistat plus DRSP/EE;group 2 included 25 patients treated with DRSP/EE *** groups got the same comprehensive intervention in terms of individualized,standardized managment and monitoring of life-style like diet and *** changes of anthropometric indices,sexual hormones,hepatorenal function parameters before and after three months of treatment in the two groups were ***:After three months of treatment,body weight,waist circumference(WC),hip circumference(HC)and BMI of both groups were significantly decreased(P0.05).Conclusion:To our knowledge our study is the first to investigate the effects of orlistat combined with DRSP/EE in overweight or obese PCOS patients comparing with the effect of using DRSP/EE *** combined with DRSP/EE was better than use DRSP/EE alone in getting weight loss,which provides an evidence for the choice of rational drug use in clinical practice.

关键词： Overweight/Obese Polycystic ovary syndrome Orlistat Drospirenone/ethinylestradiol tablets

Up to 70 THz bandwidth from an implanted Ge photoconductive antenna excited by a femtosecond Er:fibre laser

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Light(Science & Applications) 2020年第1期9卷 1716-1722页

作者： Abhishek Singh Alexej Pashkin Stephan Winnerl Malte Welsch Cornelius Beckh Philipp Sulzer alfred.Leitenstorfer Manfred Helm Harald Schneider Institute of Ion Beam Physics and Materials Research Helmholtz-Zentrum Dresden-Rossendorf01328 DresdenGermany Cfaed and Institute of Applied Physics TU Dresden01062 DresdenGermany Department of Physics and Center for Applied Photonics University of Konstanz78457 KonstanzGermany

Phase-stable electromagnetic pulses in the THz frequency range offer several unique capabilities in time-resolved ***,the diversity of their application is limited by the covered spectral *** particular,the upper frequency limit of photoconductive emitters-the most widespread technique in THz spectroscopy-reaches only up to 7 THz in the regular transmission mode due to absorption by infrared-active optical ***,we present ultrabroadband(extending up to 70 THz)THz emission from an Au-implanted Ge emitter that is compatible with mode-locked fibre lasers operating at wavelengths of 1.1 and 1.55μm with pulse repetition rates of 10 and 20 MHz,*** result opens up the possibility for the development of compact THz photonic devices operating up to multi-THz frequencies that are compatible with Si CMOS technology.

关键词： antenna emitter fibre

Management strategy of infertility in polycystic ovary syndrome

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Global Health Journal 2022年第2期6卷 70-74页

作者： Meng Li Xiangyan Ruan alfred.O.Mueck Department of Gynecological Endocrinology Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijing Maternal and Child.Health Care Hospital Yaojiayuan Road 251Beijing 100026China Department of Womens Health University Hospital Tuebingen Calwer Strasse 7Tuebingen 72076Germany

Polycystic ovary syndrome(PCOS)is the most common endocrine and metabolic disease in women of reproductive *** is characterized by ovulatory disruption,which can lead to *** with PCOS are also more likely to have poor pregnancy *** obese women,lifestyle interventions are recommended first,which have general health *** women who have difficulty changing their lifestyle,drugs for the treatment of obesity or bariatric surgery could be *** citrate is the first-line medication after weight loss that has been utilized in the *** is supplanting clomiphene as the best option for ovulation induction for now,particularly in patients with *** can improve ovulation and pregnancy rates;however,it has minimal effects in terms of raising live birth ***-line therapies include gonadotropins and laparoscopic ovary *** vitro fertilization can be utilized as a third-line treatment for patients with PCOS who have failed ovulation induction therapy or have other infertility *** summary,to achieve fertility,patients with PCOS require standardized individualized therapy.

关键词： Polycystic ovary syndrome Infertility Lifestyle modification Ovulation induction

Melting mechanisms of Pt-based multimetallic spherical nanoparticles by molecular dynamics simulation

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稀有金属：英文版 2023年第2期42卷 406-417页

作者： Chun-Yu Cheng Yuan-Yuan Guo Yi-Ming Zou Amanda Jiamin Ong alfred.ling Yoong Tok Shuzhou Li School of Materials Science and Engineering Nanyang Technological UniversitySingapore639798Singapore

The melting mechanisms of Pt-based multimetallic nanoparticles(NPs)are important to help determine their optimal melting *** understand the melting and coalescence behaviors of heterogeneous NPs(Pd-Pt NPs)with various sizes and compositions,molecular dynamics(MD)simulation was *** MD results for larger Pd-Pt NPs with an effective diameter of4.6-7.8 nm show that PtPd alloy can form at Pd/Pt interface before Pd NP melted completely,while for Pt-core/Pdshell NP and Pd-core/Pt-shell NP,PtPd alloy formed only after Pd portion melted *** smaller Pd-Pt NPs with an effective diameter of 2.5-4.0 nm,PdPt alloy is not formed until both Pd and Pt NPs melted ***,the coalescence process of Pd-Pt NPs depends on the melting temperature of Pt NP when Pt composition is higher than 20 at%.Furthermore,the melting mechanisms of Pd/Pt/Ir trimetallic NPs are investigated.A two-step melting process occurs in Pd-Pt-Ir NPs and Ir-core/Ptshell/Pd-shell NP,and the melting sequence of Pd-core/Ptshell/Ir-shell NP and Pt-core/Pd-shell/Ir-shell NP is different from Pd/Pt bimetallic NPs.

关键词： Molecular dynamics(MD) Melting mechanism Pt-based Multimetallic Heterogeneous structure