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Asymmetric biotic interchange across the Bering land bridge between Eurasia and North America

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National Science Review 2019年第4期6卷 739-745页

作者： Dechun Jiang Sebastian klaus Ya-Ping Zhang David M.Hillis Jia-Tang Li CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of Biology Chinese Academy of Sciences Department of Ecology and Evolution J.W.Goethe University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Department of Integrative Biology and Biodiversity Center University of Texas at Austin

The exchange of biotas between Eurasia and North America across the Bering land bridge had a major impact on ecosystems of both continents throughout the Cenozoic. This exchange has received particular attention regarding placental mammals dispersing into the Americas, including humans after the last glacial period, and also as an explanation for the disjunct distribution of related seed plants in eastern Asia and eastern North America. Here, we investigate bi-directional dispersal across the Bering land bridge from estimates of dispersal events based on time-calibrated phylogenies of a broad range of plant, fungus and animal taxa. We reveal a long-lasting phase of asymmetrical biotic interchange, with a peak of dispersal from Asia into North America during the late Oligocene warming(26–24 Ma), when dispersal in the opposite direction was greatly decreased. Influx from North America into Asia was lower than in the opposite direction throughout the Cenozoic, but with peak rates of dispersal at the end of the Eocene(40–34 Ma)and again in the early to middle Miocene(16–14 Ma). The strong association between dispersal patterns and environmental changes suggests that plants, fungi and animals have likely dispersed from stable to perturbed environments of North America and Eurasia throughout the Cenozoic.

关键词： multiple taxa biogeography Bering land bridge Cenozoic

Clarification on Polarity of Bipolar Electric Field Solitary Structures in Space Plasmas with Satellite Observation

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Chinese Physics Letters 2011年第2期28卷 164-167页

作者： M.N.S.Qureshi SHI Jian-Kui klaus Torkar LIU Zhen-Xing Department of Physics GC UniversityLahore 54000Pakistan State Key Laboratory of Space Weather Centre for Space Science and Applied Research(CSSAR)Chinese Academy of SciencesBeijing 100190 Space Research Institute Austrian Academy of SciencesA-8042GrazAustria

The bipolar electric field solitary(EFS)structures observed frequently in space plasmas by satellites have two different polarities,first positive electric field peak then negative(i.e.,positive/negative)and first negative then positive peak(i.e.,negative/positive).We provide the physical explanation on the polarity of observed bipolar EFS structures with an electrostatic ion fluid *** results show that if initial electric field𝐸E_(0)>0,the polarity of the bipolar EFS structure will be positive/negative;and if𝐸E_(0)<0,the polarity of the bipolar EFS structure will be negative/***,for a fixed polarity of the EFS,either positive/negative or negative/positive,if the satellite is located at the positive side of the EFS,the observed polarity should be positive/negative,if the satellite is located at the negative side of the EFS,the observed polarity should be negative/***,we provide a method to clarify the natural polarity of the EFS with observed polarity by *** results are significant to understand the physical process in space plasma with the satellite observation.

关键词： Observation polarity bipolar

Identifying the skeptics and the undecided through visual cluster analysis of local network geometry

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Visual Informatics 2022年第3期6卷 11-22页

作者： Shenghui Cheng Joachim Giesen Tianyi Huang Philipp Lucas klaus Mueller Westlake University HangzhouChina Stony Brook University NYUnited States of America Friedrich-Schiller-Universitat Jena JenaGermany Westlake Institute for Advanced Study HangzhouChina Research Center for the Industries of the Future HangzhouChina

By skeptics and undecided we refer to nodes in clustered social networks that cannot be assigned easily to any of the *** nodes are typically found either at the interface between clusters(the undecided)or at their boundaries(the skeptics).Identifying these nodes is relevant in marketing applications like voter targeting,because the persons represented by such nodes are often more likely to be affected in marketing campaigns than nodes deeply within *** far this identification task is not as well studied as other network analysis tasks like clustering,identifying central nodes,and detecting *** approach this task by deriving novel geometric features from the network structure that naturally lend themselves to an interactive visual approach for identifying interface and boundary nodes.

关键词： Graph/network data High dimensional data visualization Visualization in social and information sciences Data clustering coordinated and multiple views

A superradiant maser with nitrogen-vacancy center spins

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Science China(Physics,Mechanics & Astronomy) 2022年第1期65卷 61-70页

作者： Qilong Wu Yuan Zhang Xigui Yang Shi-Lei Su Chongxin Shan klaus Mølmer Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450052China Aarhus Institute of Advanced Studies Center for Complex Quantum SystemsDepartment of Physics and AstronomyAarhus UniversityAarhus C DK-8000Denmark

Recent experiments have demonstrated Rabi-oscillations, superradiant pulses and stimulated emission from negatively-charged nitrogen-vacancy(NV;) center spins in microwave resonators. These phenomena witness the kind of collective and strong coupling which has been the prerequisite for observation of superradiant lasing in the optical frequency regime. In this article, we investigate the possibility to employ coherence, present in both the collective NV-spin ensemble and the microwave field, to achieve a superradiant maser. Our calculations show that a superradiant maser with a linewidth below millihertz can be achieved with moderate kilohertz incoherent pumping of over 10;spins at room temperature. We show that the superradiant masing prevails in the presence of inhomogeneous broadening, and we present numerical and analytical studies of the dependence of the phenomenon on the various physical parameters.

关键词： superradiance maser NV center spins

Green tea, epigallocatechin gallate and the prevention of Alzheimer’s disease: clinical evidence

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Food Science and Human Wellness 2022年第4期11卷 765-770页

作者： klaus W.Lange Katharina M.Lange Yukiko Nakamura Department of Experimental Psychology University of RegensburgRegensburg 93040Germany

Given its increasing global prevalence,Alzheimer’s disease(AD)has become a major public health challenge *** symptomatic treatments available for AD have shown no significant efficacy,and no disease-modifying interventions are capable of slowing the progression of the *** potential of lifestyle-related factors,including diet,is increasingly recognized as an important consideration in the primary prevention of *** mechanisms potentially underlying neuroprotective effects of bioactive components contained in tea,such as(-)-epigallocatechin-3-gallate,as well as their preventive efficacy against AD,have been elucidated in preclinical ***,in contrast to the abundance of mechanistic findings in animals,clinical results demonstrating efficacy in humans are *** epidemiological studies have provided some evidence indicating that green tea consumption is associated with a reduced risk of age-related cognitive decline and AD,a causal relationship cannot be established on the basis of these *** clinical evidence regarding preventive or therapeutic effects of green tea and its bioactive components is unsatisfactory.A role of green tea in the prevention of AD cannot be recommended until well-designed,randomized,placebo-controlled clinical trials using standardized formulations confirm the purported beneficial effects of green tea.

关键词： Green tea Epigallocatechin gallate Alzheimer’s disease Neurodegeneration Prevention

A visual analytics workflow for probabilistic modeling

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Visual Informatics 2023年第2期7卷 72-84页

作者： Julien klaus Mark Blacher Andreas Goral Philipp Lucas Joachim Giesen Friedrich Schiller University Jena Germany

Probabilistic programming is a powerful means for formally specifying machine learning *** inference engine of a probabilistic programming environment can be used for serving complex queries on these *** of the current research in probabilistic programming is dedicated to the design and implementation of highly efficient inference *** less research aims at making the power of these inference engines accessible to non-expert *** programming means writing *** many potential users from promising application areas such as the social sciences lack programming *** prompted recent efforts in synthesizing probabilistic programs directly from ***,working with synthesized programs still requires the user to read,understand,and write some code,for instance,when invoking the inference engine for answering ***,we present an interactive visual approach to synthesizing and querying probabilistic programs that does not require the user to read or write code.

关键词： Probabilistic inference Bayesian network Structured query language Table-based visualization

Prodromal Parkinson’s disease: hype or hope for disease-modification trials?

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Translational Neurodegeneration 2022年第1期11卷 777-789页

作者： Philipp Mahlknecht Kathrin Marini Mario Werkmann Werner Poewe klaus Seppi Department of Neurology Innsbruck Medical University6020 InnsbruckAustria

The ultimate goal in Parkinson’s disease (PD) research remains the identification of treatments that are capable of slowing or even halting the progression of the disease. The failure of numerous past disease-modification trials in PD has been attributed to a variety of factors related not only to choosing wrong interventions, but also to using inadequate trial designs and target populations. In patients with clinically established PD, neuronal pathology may already have advanced too far to be modified by any intervention. Based on such reasoning, individuals in yet prediagnostic or prodromal disease stages, may provide a window of opportunity to test disease-modifying strategies. There is now sufficient evidence from prospective studies to define diagnostic criteria for prodromal PD and several approaches have been studied in observational cohorts. These include the use of PD-risk algorithms derived from multiple established risk factors for disease as well as follow-up of cohorts with single defined prodromal markers like hyposmia, rapid eye movement sleep behavior disorders, or PD gene carriers. In this review, we discuss recruitment strategies for disease-modification trials in various prodromal PD cohorts, as well as potential trial designs, required trial durations, and estimated sample sizes. We offer a concluding outlook on how the goal of implementing disease-modification trials in prodromal cohorts might be achieved in the future.

关键词： Neuroprotection Preclinical Prevention Epidemiology Probability Randomized controlled trial Preventive Neuroprotective

Comparison of ART outcomes in men with altered mRNA protamine 1/protamine 2 ratio undergoing intracytoplasmic sperm injection with ejaculated and testicular spermatozoa

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Asian Journal of Andrology 2020年第6期22卷 623-628页

作者： Jonas Sarasa Maria Enciso Laura Garcia Andrea Leza klaus Steger Jon Aizpurua iGLS Alicante 03540SpainMolecular AndrologyJustus-Liebig-UDiversity GiessenGiessen 35385Germany IVF-Spain Alicante 03540SpainMolecular AndrologyJustus-Liebig-UDiversity GiessenGiessen 35385Germany Department of Urology Pediatric Urology and AndrologyMolecular AndrologyJustus-Liebig-UDiversity GiessenGiessen 35385Germany

Assisted reproductive technologies invoIving the use of spermatozoa and eggs for in vitro fertilization(IVF)have come as the solution for many infertile couples to become ***,in some cases,the use of ejaculated spermatozoa delivers poor IVF *** studies have suggested the use of testicular spermatozoa in severe male in fertility cases,but no guideli nes regarding their utilization are currently *** the present study,we found the mRNA protamine 1/protamine 2(P1/P2)ratio to be a valuable biomarker of poor sperm function that could be used as a diagnostic key for the identification of cases that would benefit from the use of testicular spermatozoa.A total of 23 couples undergoing egg donation cycles with at least one previous cycle failure were *** couples underwent two consecutive intracytoplasmic sperm injection(ICSI)cycles with either ejaculated or testicular spermatozoa(TESA).The sperm mRNA P1/P2 ratio,fertilization rate,blastocyst rate,and pregnancy and live birth rate were *** showed improved ICSI and clinical outcomes in cycles with testicular spermatozoa in men with altered mRNA P1/P2 *** cycles presented significantly higher rates of fertilization(mean±standard deviation:76.1%±15.1%vs 65.5%±18.8%),blastocyst formation(55.0%±20.3%vs 30.8%±23.8%),and good morphological quality blastocyst(28.9%±22.9%vs 13.5%±17.9%)and also improvements on pregnancy(60.9%vs 0%)and healthy birth rates(56.5%vs 0%)than EJACULATE *** results described here suggest that in patients with previous IVF/ICSI failures and aberrant mRNA protamine ratios,the use of testicular spermatozoa may be a good alternative to improve clinical outcomes.

关键词： DNA damage male infertility mRNA protamine ratio sperm chromatin testicular spermatozoa

Cost management for university libraries /

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