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Circularly polarized phosphorescence and photon transport of micro/nanocrystals of ruthenium and iridium complexes with chiral anions

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science China Chemistry 2023年第10期66卷 2892-2902页

作者： Zhong-Qiu Li Zhong-Liang Gong Tongling Liang stefan Bernhard Yu-Wu Zhong Jiannian Yao Beijing National Laboratory for Molecular sciences(BNLMs) CAS Key Laboratory of PhotochemistryCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China school of Chemical sciences University of Chinese Academy of SciencesBeijing 100049China Department of Chemistry Carnegie Mellon UniversityPittsburghPennsylvania 15213USA

Materials with efficient circularly polarized phosphorescences(CPPs) are of potential use in advanced data encryption and anticounterfeiting, bioimaging, optoelectronic devices and so forth. Herein, a simple method is presented for the preparations of CPP-active micro/nanocrystals with large luminescence dissymmetry factors(glum), high phosphorescence quantum efficiencies(Φ_(P)) and tunable emission colors. Diastereomeric Ir^(Ⅲ) and Ru^(Ⅱ) complexes with chiral(±)-camphorsulfonate counter-anions are readily synthesized and assembled into crystalline microrods, microplates or nanofibers with ordered morphologies. The chirality information of chiral counter-anions is efficiently transferred to the metal components to afford CPPs with cyan, green,yellow, or red emission colors and Φ_(P)in the range of 5%–85%. The number of chiral anions is found to play a role in influencing the CPP magnitudes of these crystals. The dicationic Ru^(Ⅱ) and tricationic Ir^(Ⅲ) complexes show glumvalues in the 10^(-2)order, which are much larger with respect to those of monocationic Ir^(Ⅲ) complexes. single crystal X-ray analysis is performed to obtain information on the chirality transfer of these materials. In addition, circularly polarized photonic signal waveguiding is demonstrated using the microcrystals of an Ir^(Ⅲ)complex. This work demonstrates an appealing strategy of constructing chiral micro/nano-architectures for potential applications in chiral nanophotonics.

关键词： circularly polarized luminescence transition metal complexes chirality transfer micro/nanocrystals photon transport

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Assessing citizen science opportunities in forest monitoring using probabilistic topic modelling

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Forestry studies in China 2014年第2期16卷 93-104页

作者： stefan Daume Matthias Albert Klaus von Gadow Faculty of Forest sciences and Forest Ecology Georg-August-University GttingenBüsgenweg 537077 GttingenGermany Department of Biodiversity Informatics Swedish Museum of Natural HistoryBox 5000710405 StockholmSweden Northwest German Forest Research Institute Grtzelstraβe 237079 GttingenGermany

Background： With mounting global environmental, social and economic pressures the resilience and stability of forests and thus the provisioning of vital ecosystem services is increasingly threatened. Intensified monitoring can help to detect ecological threats and changes earlier, but monitoring resources are limited. Participatory forest monitoring with the help of ＂citizen scientists＂ can provide additional resources for forest monitoring and at the same time help to communicate with stakeholders and the general public. Examples for citizen science projects in the forestry domain can be found but a solid, applicable larger framework to utilise public participation in the area of forest monitoring seems to be lacking. We propose that a better understanding of shared and related topics in citizen science and forest monitoring might be a first step towards such a framework. Methods： We conduct a systematic meta-analysis of 1015 publication abstracts addressing ＂forest monitoring＂ and ＂citizen science＂ in order to explore the combined topical landscape of these subjects. We employ ＇topic modelling an unsupervised probabilistic machine learning method, to identify latent shared topics in the analysed publications. Results： We find that large shared topics exist, but that these are primarily topics that would be expected in scientific publications in general. Common domain-specific topics are under-represented and indicate a topical separation of the two document sets on ＂forest monitoring＂ and ＂citizen science＂ and thus the represented domains. While topic modelling as a method proves to be a scalable and useful analytical tool, we propose that our approach could deliver even more useful data if a larger document set and full-text publications would be available for analysis. Conclusions： We propose that these results, together with the observation of non-shared but related topics, point at under-utilised opportunities for public participation in forest monitoring.

关键词： Forest monitoring Citizen science Participatory forest monitoring Probabilistic topic modelling Text analysis

Castleman’s disease presented as a rare unicentric pancreatic mass

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Hepatobiliary & Pancreatic Diseases International 2019年第6期18卷 590-592页

作者： Velimir Markovic Dejan stojakov Marijan Micev stefan Kmezic dusan saponjski Zoran Krivokapic Clinic for Digestive surgery–First surgical Clinic Clinical Center of SerbiaBelgradeSerbia school of Medicine University of BelgradeSerbia KBC“Dragisa Misovic” BelgradeSerbia Department of Abdominal Radiology Center for Radiology and MRIClinical Center of SerbiaBelgradeSerbia

A 44-year-old male patient was initially presented with pain in the upper *** loss,jaundice and digestive disorders were not *** analysis showed white blood cell count 9.02×10^9,C-reactive protein(CRP)3 mg/L,and gastrin 38 ng/*** ultrasonography revealed tumor in the projection of duodenum and pancreatic *** and tumor markers(CA19-9,CEA,CA72-4,and AFP)were all negative.

关键词： Blood gastrin Colon

作物多样性实验:理解一年生作物系统物种多样性效应的机理

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Journal of Plant Ecology 2023年第6期16卷 31-45页

作者： Christian schob Nadine Engbersen Jesús López-Angulo Anja schmutz Laura stefan Area de Biodiversidad y Conservación Universidad Rey Juan Carlos28933 MóstolesMadridSpain Agriculture and Forestry Division Canton Lucerne6210 SurseeSwitzerland Institute of Agricultural sciences ETH Zurich8092 ZurichSwitzerland Cultivation Techniques and Varieties for Arable Crops Agroscope1260 NyonSwitzerland

受到草地生物多样性实验研究植物多样性对初级生产力影响的启发,2018年建立的“作物多样性实验”旨在测试自然生态系统生物多样性的效应是否也适用于一年生作物系统,以及作物混合种植(简称作物混作)是否也能实现超产,即作物混作的产量... 详细信息

受到草地生物多样性实验研究植物多样性对初级生产力影响的启发,2018年建立的“作物多样性实验”旨在测试自然生态系统生物多样性的效应是否也适用于一年生作物系统,以及作物混合种植(简称作物混作)是否也能实现超产,即作物混作的产量超过作物单作的最高产量。实验的前3年结果表明,作物混作不仅增加了产量,而且通常也比最高产的作物单作产量高。作物多样性效应在环境胁迫下更显著,且通常是在与豆科作物混作时实现超产。然而,我们也观察到在有利条件下和没有豆科植物的混作中,也有超产现象。对产量效应的潜在机制研究发现,作物物种之间存在直接的互补关系和通过其他生物的间接效应。前者包括氮吸收中的化学、空间和时间互补性,水分吸收的根分布互补性,以及光利用的空间和时间互补性。在间接机制中,除了“作物多样性实验”中未研究但在其他研究得到证明的对害虫和疾病的互补抑制之外,我们还证明作物混作中对杂草的互补抑制和植物生长促进微生物的丰度更高。因此,“作物多样性实验”不仅支持了生物多样性实验所证明的生态过程,也支持了作物系统中的生物多样性的生态系统功能假设,而且作物物种多样化的作物系统为可持续生产食物提供了有价值工具。

关键词：间作生物多样性产量竞争促进互补效应混合种植

Wave propagation through disordered media without backscattering and intensity variations

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Light(science & Applications) 2017年第1期6卷 623-629页

作者： Konstantinos G Makris Andre Brandstötter Philipp Ambichl Ziad H Musslimani stefan Rotter Crete Center for Quantum Complexity and Nanotechnology Department of PhysicsUniversity of CreteHeraklion 71003Greece Institute for Theoretical Physics Vienna University of Technology(TU-Wien)Vienna 1040Austria Department of Mathematics Florida State UniversityTallahasseeFL 32306USA

A fundamental manifestation of wave scattering in a disordered medium is the highly complex intensity pattern the waves acquire due to multi-path *** we show that these intensity variations can be entirely suppressed by adding disorder-specific gain and loss components to the *** resulting constant-intensity waves in such non-Hermitian scattering landscapes are free of any backscattering and feature perfect transmission through the *** experimental demonstration of these unique wave states is envisioned based on spatially modulated pump beams that can flexibly control the gain and loss components in an active medium.

关键词： Anderson localisation complex media non-Hermitian physics scattering

Correlation between the results of three physical fitness tests(endurance,strength,speed) and the output measured during a bicycle ergometer test in a cohort of military servicemen

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Journal of Medical Colleges of PLA(China) 2016年第3期31卷 134-139页

作者： stefan sammito Nils Gundlach Irina B?ckelmann Bundeswehr Medical service Headquarters Section Health PromotionSports and Nutrition Medicine Otto von Guericke University Magdeburg Medical FacultyDepartment of Occupational Medicine Bundeswehr Medical Clinic Rotenburg

Background: Physical fitness tests are widely used to assess endurance,sprint ability,coordination and/or *** objective of the present study was to analyze the degree to which the results of the Bundeswehr Basis Fitness Test(BFT)–a physical fitness test comprising a sprint test(11×10-m shuttle test),a flexed-arm hang test and a 1000-m run–are consistent with the output measured during a bicycle ergometer *** number of false-positive and falsenegative results with regard to the assessment of physical fitness were also ***: As part of a retrospective study,health assessments from 323 reenlistment examinations were evaluated regarding the output measured during a bicycle ergometer test and compared with the BFT results of the ***: Overall,a good correlation was shown between the bicycle ergometer test results and the results achieved in the BFT *** three disciplines of the BFT showed a highly significant correlation with the relative output achieved during the bicycle ergometer test(Pso,the overall BFT score was highly significantly correlated(Pse-positive and false-negative results was 4.0%.Conclusion: The BFT results measured in the three physical fitness test items were highly correlated with the output measured during the bicycle ergometer *** rate of false-positive and false-negative results was *** test items thus represent an appropriate measurement instrument because the test items require few equipment and less ***,a large number of subjects can be *** suggest that it would be more useful to assess the physical fitness of this special group exclusively on the basis of the BFT instead of using the bicycle ergometer test.

关键词： Physical fitness Military Ergometer test Bicycle Treadmill

High temperature oxidation of inoculated high si/siMo ductile cast irons in air and combustion atmospheres

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China Foundry 2024年第5期21卷 555-562页

作者： Iuliana stan Mihai Chisamera Robert Lascu Codrut Cariga Eduard stefan stelian stan Denisa Anca Iulian Riposan National University of science and Technology POLITEHNICA Bucharest Materials Science and Engineering Faculty313 Splaiul IndependenteiSector 6060042 BucharestRomania

The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%si and 4.8%si-2.3%Mo in dry air and combustion gas containing water vapour(natural gas burning).The oxidation is influenced by the gas atmosphere type,the iron alloying system,and the inoculating elements depending on the heating *** weight gain increases from 0.001%-0.1%(400°C)to 0.05%-0.70%(600°C)and up to 0.10%-2.15%(800°C).No particular effects of the considered influencing factors are found when heating at 400°C,while at 600°C,mainly the oxidation gas atmosphere type shows a visible *** the highest heating temperature of 800°C,a limited increase of the weight gain is found for dry air atmosphere(up to 0.25%),but it drastically increases for combustion atmospheres(0.65%-2.15%).The water vapour presence in the combustion atmosphere is an important oxidising factor at 600-800°*** alloying system appears to influence the oxidation behavior mainly at a heating temperature of 800°C in the combustion atmosphere,as evidenced by the lower weight gain in 5.25%silicon cast *** effects of inoculating elements increase with the heating temperature,with Ca and Ba-Fesi inoculation generally showing better *** inoculated with CaRE-Fesi exhibit a higher degree of *** results are in good relationship with the previous reported data:Ca-Ba-inoculation system appears to be better than simple Ca for improving the graphite parameters,while RE-bearing inoculant negatively affects the compactness degree of graphite particles in high-si ductile *** the lower compactness degree is typical for graphite nodules in high-si ductile irons,which negatively affects the oxidation resistance,it is necessary to employ specific metallurgical treatments to improve nodule ***,in particular,is a potential method to achieve this improvement.

关键词： ductile iron spheroidal graphite si/siMo oxidation air/combustion atmospheres FesiCaMgRE treatment Ca,Ca-Ba,Ca-RE inoculation structure characteristics

B cell development is critically dependent on NFATc1 activity

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Cellular & Molecular Immunology 2019年第5期16卷 508-520页

作者： sabrina Giampaolo Gabriela Wojcik stefan Klein-Hessling Edgar serfling Amiya K.Patra Department of Molecular Pathology Institute of PathologyUniversity of WürzburgJosef Schneider-Str.297080 WürzburgGermany Institute of Translational and stratified Medicine Faculty of Medicine and DentistryUniversity of PlymouthPlymouth PL68BUUK Comprehensive Cancer Center Mainfranken University of WürzburgJosef Schneider-Str.697080 WürzburgGermany

B cell development in bone marrow is a precisely regulated complex *** successive stages of differentiation,which are regulated by a multitude of signaling pathways and an array of lineage-specific transcription factors,the common lymphoid progenitors ultimately give rise to mature B *** to early thymocyte development in the thymus,early B cell development in bone marrow is critically dependent on IL-7 *** this IL-7-dependent stage of differentiation,several transcription factors,such as E2A,EBF1,and Pax5,among others,play indispensable roles in B lineage specification and *** recent studies have implicated several other transcription factors in B cell development,the role of NFATc1 in early B cell developmental stages is not ***,using multiple gene-manipulated mouse models and applying various experimental methods,we show that NFATc1 activity is vital for early B cell *** of NFATc1 activity in pro-B cells suppresses EBF1 expression,impairs immunoglobulin gene rearrangement,and thereby preBCR formation,resulting in defective B cell ***,deficiency in NFATc1 activity arrested the pro-B cell transition to the pre-B cell stage,leading to severe B cell *** findings suggest that,along with other transcription factors,NFATc1 is a critical component of the signaling mechanism that facilitates early B cell differentiation.

关键词： Differentiation EBF1 NFATc1 Pro-B Pre-B

Autoencoder-based anomaly root cause analysis for wind turbines

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Energy and AI 2021年第2期4卷 57-65页

作者： Cyriana M.A.Roelofs Marc-Alexander Lutz stefan Faulstich stephan Vogt Fraunhofer IEE Konigstor 59Kassel 34119Germany Intelligent Embedded systems Universitat KasselWilhelmshoher Allee 67Kassel 34121Germany

A popular method to detect anomalous behaviour or specific failures in wind turbine sensor data uses a specific type of neural network called an *** models have proven to be very successful in detecting such deviations,yet cannot show the underlying cause or failure *** information is necessary for the implementation of these models in the planning of maintenance *** this paper we introduce a novel method:*** use ARCANA to identify the possible root causes of anomalies detected by an *** describes the process of reconstruction as an optimisation problem that aims to remove anomalous properties from an anomaly *** reconstruction must be similar to the anomaly and thus identify only a few,but highly explanatory anomalous features,in the sense of Ockham’s *** proposed method is applied on an open data set of wind turbine sensor data,where an artificial error was added onto the wind speed sensor measurements to acquire a controlled test *** results are compared with the reconstruction errors of the autoencoder *** ARCANA method points out the wind speed sensor correctly with a significantly higher feature importance than the other features,whereas using the non-optimised reconstruction error does *** though the deviation in one specific input feature is very large,the reconstruction error of many other features is large as well,complicating the interpretation of the detected ***,we apply ARCANA to a set of offshore wind turbine *** case studies are discussed,demonstrating the technical relevance of ARCANA.

关键词： Anomaly detection Autoencoder Root cause analysis Predictive maintenance Wind turbine Explainable artificial intelligence