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Self-assembled bright luminescent hierarchical materials from a tripodal benzoate antenna and heptadentate Eu(III) and Tb(III) cyclen complexes

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Frontiers of Chemical Science and Engineering 2019年第1期13卷 171-184页

作者： Aramballi J.Savyasachi David F.Caffrey Kevin Byrne Gerard Tobin Bruno D'Agostino wolfgang schmitt Thorfinnur Gunnlaugsson School of Chemistry and Trinity Biomedical Sciences Institute (TBSI) University of Dublin Trinity College Dublin Dublin 2 Ireland School of Chemistry and Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) University of Dublin Trinity College Dublin Dublin 2 Ireland

The europium heptadentate coordinatively unsaturated (Eu(III)) and the terbium (Tb(III)) 1,4,7,10-tetraazacyclododecane (cyclen) complexes 1 and 2 were used in conjunction with ligand 3 (1,3,5-benzene-trisethynylbenzoate) to form the supramolecular self-assembly structures 4 and 5;this being investigated in both the solid and the solution state. The resulting self-assemblies gave rise to metal centered emission (both in the solid and solution) upon excitation of 3, confirming its role as a sensitizing antenna. Drop-cased examples of ligand 3, and the solid forms of 4 and 5, formed from both organic and mixture of organic-aqueous solutions, were analyzed using Scanning Electron Microscopy, which showed significant changes in morphology;the ligand giving rise to one dimensional structures, while both 4 and 5 formed amorphous materials that were highly dense solid networks containing nanoporous features. The surface area (216 and 119 m2·g^-1 for 4 and 5 respectively) and the ability of these porous materials to capture and store gases such as N2 investigated at 77 K. The self-assembly formation was also investigated in diluted solution by monitoring the various photophysical properties of 3–5. This demonstrated that the most stable structures were that consisting of a single antennae 3 and three complexes of 1 or 2 (e.g., 4 and 5) in solution. By monitoring the excited state lifetimes of the Eu(III) and Tb(III) ions in H2O and D2O respectively, we showed that their hydration states (the q-value) changed from -2 to 0, upon formation of the assemblies, indicating that the three benzoates of 3 coordinated directly to the each of the three lanthanide centers. Finally we demonstrate that this hierarchically porous materials can be used for the sensing of organic solvents as the emission is highly depended on the solvent environment;the lanthanide emission being quenched in the presence of acetonitrile and THF, but greatly enhanced in the presence of methanol.

关键词： self-assembly supramolecular chemistry lanthanides Eu(III) and Tb(III) complexes luminescence metallostars

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Going deep:Roots,carbon,and analyzing subsoil carbon dynamics

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Molecular Plant 2024年第1期17卷 1-3页

作者： Ezhilmathi Angela Joseph Fernando Michael Selvaraj Yusaku Uga wolfgang Busch Hunt Bowers Joe Tohme Alliance of Bioversity International and CIAT Km 17 Recta Cali-PalmiraAprtado Aereo 6713Cali 763537Colombia National Institute of Agrobiological Sciences(NIAS) TsukubaIbaraki 305-0856Japan Salk Institute for Biological Studies 10010 N Torrey Pines RoadLa JollaCA 92037USA Earth Optics Suite 840ArlingtonVA 22202USA

Agricultural practices currently contribute to the emission of approximately 10%–12%atmospheric greenhouse gasses,with tillage agriculture accelerating soil disruption and carbon dioxide ***,various options exist,such as converting new lands for agriculture,promoting healthier plant-based diets,adopting advanced management technologies,and minimizing food ***,these measures alone are insufficient to ensure environmental sustainability within planetary boundaries.

关键词： soil measures carbon

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EVA NEXUS-Phaco performance study

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1447-1452页

作者： Lukas Feldhaus Andreas Ohlmann Stefan Kassumeh Siegfried Priglinger wolfgang Mayer Department of Ophthalmology University HospitalLudwig-Maximilians-University MunichMunich 80336Germany

AIM:To investigate a novel phacoemulsification system“EVA NEXUS”(D.O.R.C.,Dutch Opthalmic Research Center)in comparison to the existing system“EVA”in clinical *** to compare both phacoemulsification systems in terms of efficiency,safety and postoperative inflammatory ***:In this study standardized cataract surgery was performed on both eyes of the study participant,using the“EVA system”(control group,n=20)on one eye and the“EVA NEXUS system”(intervention group,n=20)on the other *** patients with cataract LOCS Grading 1-3 and no accompanying eye diseases were included in this study.A total of 20 patients were included in this study,with each treatment arm including 20 *** surgery a 0.1 mL aqueous humor sample was collected 1min after phacoemulsification to measure the total prostaglanin E2 concentrations using an enzyme-linked immunosorbent *** endothelial cell count,visual and refractive outcomes,and anterior chamber flare were evaluated preoperatively,and 1d,1wk,and 3mo ***:There were no statistically significant differences between both groups regarding intraoperative safety parameters including effective phacoemulsification time(P=0.904),balanced saline solution flow(P=0.701)and total surgery time(P=0.565).Postoperative prostaglandin E2 levels,anterior chamber flare as well as endothelial cell loss tended to be lower in the NEXUS-Group,however not being statistically significant(P=0.718;0.164;0.486).Both systems provided similar clinical outcomes,regarding best corrected visual acuity and refractive parameters,showing no statistically significant differences between both ***:Both systems show a high level of safety and efficency with similar results in terms of safety parameters including postoperative inflammatory activity and endothelial cell loss as well as visual and refractive *** statistically not significant,the EVA NEXUS system tends to cause less postoperative inflammatio

关键词： cataract surgery phacoemulsification fluidics instrument

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Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： Hans-Georg ENKLER wolfgang KUNERT Stefan PFEFFER Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK Christoph REICH Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the *** some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced *** The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue *** VR controllers are limited regarding haptic *** haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training *** To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic *** is currently calculated and visually displayed to the user in the VR *** the prototype controller,a first axis was provided with perceptible feedback for test *** of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard *** The first prototype enables full operation of a virtual laparoscopic instrument in *** addition,the simulation can compute simple interaction *** challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic *** weaknesses were identified in the first hardware prototype,which will be improved in subsequent *** degrees of freedom of the controller are to be provided with haptic *** make forces t

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

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Numerical Optimization by Finite Element Method of Stainless Steel/Glass-Epoxy Composite Bolted Joint under Tension and Compression

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Engineering（科研） 2024年第4期16卷 102-122页

作者： Christian schmitt Arnaud Kremeur Pawel Lipinski Julien Capelle National Engineering School of Metz University of Lorraine Metz France

The aim of this study was to optimize the geometry and the design of metallic/composite single bolted joints subjected to tension-compression loading. For this purpose, it was necessary to evaluate the stress state in each component of the bolted join. The multi-material assembly was based on the principle of double lap bolted joint. It was composed of a symmetrical balanced woven glass-epoxy composite material plate fastened to two stainless sheets using a stainless pre-stressed bolt. In order to optimize the design and the geometry of the assembly, ten configurations were proposed and studied: a classical simple bolted joint, two joints with an insert (a BigHeadR insert and a stair one) embedded in the composite, two “waved” solutions, three symmetrical configurations composed of a succession of metallic and composites layers, without a sleeve, with one and with two sleeves, and two non-symmetrical constituted of metallic and composites layers associated with a stair-insert (one with a sleeve and one without). A tridimensional Finite Element Method (FEM) was used to model each configuration mentioned above. The FE models taked into account the different materials, the effects of contact between the different sheets of the assembly and the pre-stress in the bolt. The stress state was analyzed in the composite part. The concept of stress concentration factor was used in order to evaluate the stress increase in the highly stressed regions and to compare the ten configurations studied. For this purpose, three stress concentration factors were defined: one for a monotonic loading in tension, another for a monotonic loading in compression, and the third for a tension-compression cyclic loading. The results of the FEM computations showed that the use of alternative metallic and composite layers associated with two sleeves gived low values of stress concentration factors, smaller than 1.4. In this case, there was no contact between the bolt and the composite pa

关键词： Bolted Joint Glass-Epoxy Composite Clearance Hybrid Steel-Composite

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Development of Framework for ACI-Powered Human Resource Recruitment Assistant

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Management Studies 2024年第3期12卷 182-187页

作者： Md Jawadur Rahman Gabriele M.Murry Stephanie schmitt-Rüth OTH Amberg-Weiden AmbergGermany

The landscape of human resource management within large enterprises necessitates efficient and unbiased recruitment practices to ensure organisational effectiveness and foster diversity(Ayoko&Fujimoto,2023).Traditional hiring processes often create biases,which cause additional challenges in achieving proper objectives(Bogen,2021).According to Workable(***),the average time to fill a job requisition is 41 days(Howden,2023).This paper proposes a framework for the development and implementation of an Artificially Capable Intelligent(ACI)-powered Human Resource(HR)Assistant for large enterprises(possibly more than 300 employees)to eliminate these unnecessary challenges caused by biases in hiring practices,therefore directly addressing fair and just participation in society and the world of *** framework integrates ACI technologies,particularly candidate identification,to revolutionise HR *** leveraging ACI algorithms,the proposed hyper-realistic assistant aims to revolutionise the recruitment *** will significantly reduce the average time to fill job ***,the ACI-powered system is designed to mitigate biases inherent in traditional hiring practices,thus fostering a fair and inclusive environment for all candidates in the shortest possible time *** paper includes the key components and working processes of the ACI-powered HR Assistant *** a comprehensive theoretical analysis,the paper investigates the system’s working process and how the framework aligns with the goal of promoting a fair and participatory environment in the world of ***,the proposed framework represents a main step towards enhancing organisational effectiveness,fostering diversity,and advancing equitable recruitment practices in the futuristic workplace.

关键词： artificial capable intelligence human resource

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Customized molecular tools to strengthen metabolic engineering of cyanobacteria

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Green Carbon 2024年第2期2卷 149-163页

作者： Stephan Klähn Franz Opel wolfgang R.Hess Department of Solar Materials Biotechnology Helmholtz Centre for Environmental Research–UFZLeipzig 04318Germany Genetics and Experimental Bioinformatics Albert-Ludwig University FreiburgFreiburg im Breisgau 79104Germany

Cyanobacteria are promising oxygenic phototrophs for the production of various *** their(photo)biotechnological exploitation,molecular tools are required,such as,for the introduction and expression of heterologous genes,or the modulation of enzyme activities or entire *** and strategies for the development of photosynthetic biomanufacturing technologies based on cyanobacteria have been extensively reviewed,as well as certain specialized aspects of their genetic ***,options for metabolic engineering of specific cyanobacterial cells are still less developed than those for other bacteria of biotechnological *** addition to the standard genetic toolbox for“classical”metabolic engineering,we emphasize certain aspects,including recently developed vector systems for the extrachromosomal maintenance of genes and approaches based on clustered regularly interspaced short palindromic repeats(CRISPR)*** highlight the development of custom molecular tools for specific strains or products,discuss the emerging use of small regulatory proteins that appear promising for advanced metabolic engineering approaches to promote specific product formation,and provide an overview of suitable online ***,we discuss the current trends in this field and indicate their potential,such as using suitable product sensors that enable systematic screening,and optimization approaches.

关键词： Metabolic engineering Cyanobacteria Synthetic plasmids Regulatory proteins Sensors

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264米的美国魔鬼塔为什么全球登顶者不足百人？

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环球人文地理 2024年第13期 90-97页

作者：李嘉麟 Dan Gary GRP Imagery kellyvandellen Kyle samantha Jacob wolfgang flickr

在美国怀俄明州，有一座不足300米的“矮山”。别看它不高，论起攀登难度，就连珠峰登顶者都对它望洋兴叹。在美国怀俄明州东北部，有一座由火山岩和沉积岩构成的圆柱形岩石塔——魔鬼塔。它矗立在一望无际的草原上，显得格外突兀。谁...

在美国怀俄明州，有一座不足300米的“矮山”。别看它不高，论起攀登难度，就连珠峰登顶者都对它望洋兴叹。在美国怀俄明州东北部，有一座由火山岩和沉积岩构成的圆柱形岩石塔——魔鬼塔。它矗立在一望无际的草原上，显得格外突兀。谁能相信，近百年来，能够登上264米塔顶的登山者不足百人。那么，魔鬼塔是怎么形成的呢？这个问题，让好事者争论了一百多年。

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A Maintenance Service Improvement Approach Based on Queue Networks: Application

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Open Journal of Applied Sciences 2024年第2期14卷 425-440页

作者： Aslain Brisco Ngnassi Djami wolfgang Nzié Boukar Ousman Joseph Nkongho Anyi Ulrich Ngnassi Nguelcheu Department of Fundamental Sciences and Techniques of Engineer Chemical Engineering and Mineral Industries School University of Ngaoundere Ngaoundere Cameroon Laboratory of Mechanics Materials and Photonics National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department of Electrical Engineering Energy and Automation National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Laboratory E3M Faculty of Industrial Engineering University of Douala Douala Cameroon Department of Physics Faculty of Science University of Ngaoundere Ngaoundere Cameroon

The quest to increase the performance of production systems that have become complex leads to the transfer to the maintenance function of the responsibility of guaranteeing the availability of such systems. Also, we will never stop saying that maintenance must integrate into all of the company’s initiatives, to affirm its role, which is to ensure greater availability and sustainability of the means of production. The objective of this paper is to evaluate the reliability and availability of a system without knowing the distribution law of the operating times. Among the methods for evaluating dependability criteria (Fault Trees, Petri Nets, etc.), we are interested in queues that have the advantage of taking into account functional dependencies, thus allowing a quantified optimization of maintenance. Indeed, queues make it possible to model parallel or sequential processes, implementing operations taking place at the same time or one after the other, meeting the needs of modeling production systems. The main result of this paper is the study of the influence of availability on the reliability of a multi-state production system.

关键词： Markov Chains Queues Availability Reliability Maintenance

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Evaluation of the Reliability of a System: Approach by Monte Carlo Simulation and Application

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Open Journal of Applied Sciences 2024年第3期14卷 721-739页

作者： Aslain Brisco Ngnassi Djami Jean Bosco Samon Boukar Ousman Ulrich Ngnassi Nguelcheu wolfgang Nzié Guy Edgar Ntamack Bienvenu Kenmeugne Department of Fundamental Sciences and Techniques of Engineer Chemical Engineering and Mineral Industries School University of Ngaoundere Ngaoundere Cameroon Department of Mechanical Engineering National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department of Electrical Engineering Energy and Automation National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department of Physics Faculty of Science University of Ngaoundere Ngaoundere Cameroon Department of Industrial and Mechanical Engineering National Advanced School of Engineering University of Yaounde I Yaounde Cameroon

The objective of this paper is to evaluate the reliability of a system in its different states (absence of failures, partial failure and total failure) and to propose actions to improve this reliability by an approach based on Monte Carlo simulation. It consists of a probabilistic evaluation based on Markov Chains. In order to achieve this goal, the functionalities of Markov Chains and Monte Carlo simulation steps are deployed. The application is made on a production system. .

关键词： Evaluation Reliability Monte Carlo Markov Chain

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