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Light-induced halide segregation in perovskites with wrinkled morphology

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Journal of Energy Chemistry 2022年第8期31卷 83-88,I0003页

作者： Eduardo G.Machado Paulo E.Marchezi Eralci M.Therézio JoséCarlos Germino Rodrigo Szostak Caique Sde Brito Yara G.Gobato Ernesto C.Pereira Michael F.Toney Raphael Nagao Ana flávia Nogueira Institute of Chemistry University of CampinasCampinas 13083-970 SPBrazil Center for Innovation on New Energies University of CampinasCampinas 13083-970SPBrazil Institute of Physics Federal University of Mato GrossoCuiaba 78060-900MTBrazil Department of Physics Federal University of Sao CarlosSao Carlos 13565-905SPBrazil Department of Physics and i3N–Institute for Nanostructures Nanomodulation and NanofabricationUniversity of AveiroAveiro 3810-193Portugal Department of Chemistry Federal University of Sao CarlosSao Carlos 13565-905SPBrazil Renewable and Sustainable Energy Institute(RASEI) University of Colorado BoulderBoulder CO 80309ColoradoUnited States of America

In this work, it is proposed that, upon light incidence, a halide segregation event takes place, where iodine anions move towards the hills of a wrinkled mixed-halide perovskite.

关键词： halide perovskite iodine

电化学去合金化Pt(Pd)-Cu对氧的电催化还原活性的研究

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电化学 2012年第2期18卷 146-150页

作者：杨瑞枝 Peter Strasser michael toney 苏州大学能源学院江苏苏州215006 斯坦福大学材料和能源科学研究所美国斯坦福94025 斯坦福美国国家同步辐射光源中心美国斯坦福94025 柏林科技大学化学化工学院德国柏林10623

应用电化学去合金法制备了表面覆盖有Pt(Pd)原子层的Pt(Pd)-Cu合金催化剂.研究该催化剂在0.1mol.L-1HClO4酸性溶液中对氧气电化学还原的催化活性,并采用同步辐射反常X-射线衍射法(Anomalous X-ray Diffraction,AXRD)和表面X-射线散射法(... 详细信息

应用电化学去合金法制备了表面覆盖有Pt(Pd)原子层的Pt(Pd)-Cu合金催化剂.研究该催化剂在0.1mol.L-1HClO4酸性溶液中对氧气电化学还原的催化活性,并采用同步辐射反常X-射线衍射法(Anomalous X-ray Diffraction,AXRD)和表面X-射线散射法(Surface X-ray Scattering,SXS)从原子尺度研究了去合金化后催化剂的结构.分析对比纳米颗粒、薄膜和单晶3种不同形式的去合金化Pt-Cu的结构和催化活性以及Pt-Cu和Pd-Cu两种不同合金薄膜的结构和催化活性.结果表明,表面应力是影响催化剂催化活性的关键因素,而应力大小则与去合金化后所形成的表面Pt(Pd)层的厚度相关,材料尺寸和组成元素等都影响表面Pt(Pd)层的厚度.提出可利用调控材料表面的应力来设计高催化活性的催化剂.

关键词：氧电化学还原电化学去合金 Pt(Pd)-Cu合金电催化剂

Building geospatial infrastructure

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Geo-Spatial Information Science 2020年第1期23卷 1-9页

作者： Jack Dangermond michael f.Goodchild Esri RedlandsCAUSA Department of Geography University of CaliforniaSanta BarbaraCAUSA

Many visions for geospatial technology have been advanced over the past half century.Initially researchers saw the handling of geospatial data as the major problem to be overcome.The vision of geographic information systems arose as an early international consensus.Later visions included spatial data infrastructure,Digital Earth,and a nervous system for the planet.With accelerating advances in information technology,a new vision is needed that reflects today’s focus on open and multimodal access,sharing,engagement,the Web,Big Data,artificial intelligence,and data science.We elaborate on the concept of geospatial infrastructure,and argue that it is essential if geospatial technology is to contribute to the solution of problems facing humanity.

关键词： Spatial data handling National Spatial Data Infrastructure Digital Earth Big Data citizen engagement

Preface to the focused Issue on High-Order Numerical Methods for Evolutionary PDEs

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Communications on Applied Mathematics and Computation 2023年第2期5卷 529-531页

作者： Arturo Hidalgo michael Dumbser Eleuterio f.Toro Departamento de Ingeniería Geológica y Minera Escuela Técnica Superior de Ingenieros de Minas y EnergíaCenter for Computational SimulationUniversidad Politécnica de MadridRíos Rosas2128003 MadridSpain Department of Civil Environmental and Mechanical EngineeringUniversity of TrentoVia Mesiano 7738123 TrentoItaly

The underlying fields of this special issue of CAMC include mathematical modeling through evolutionary partial differential equations(PDEs),advanced high-order non-lin-ear numerical methods for their approximation and applications in various engineering branches,in physics,biology and medicine,to name but a few.Of special interest are math-ematical models based on systems of hyperbolic balance laws,including stiff source terms.

关键词： hyperbolic stiff approximation

fundamentals of case study research in family medicine and community health

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family Medicine and Community Health 2019年第2期7卷 45-52页

作者： Sergi fàbregues michael D fetters Department of Psychology and Education Universitat Oberta de CatalunyaBarcelonaSpain Department of family Medicine University of MichiganAnn ArborMichiganUSA

The aim of this article is to introduce family medicine researchers to case study research,a rigorous research methodology commonly used in the social and health sciences and only distantly related to clinical case reports.The article begins with an overview of case study in the social and health sciences,including its definition,potential applications,historical background and core features.This is followed by a 10-step description of the process of conducting a case study project illustrated using a case study conducted about a teaching programme executed to teach international family medicine resident learners sensitive examination skills.Steps for conducting a case study include(1)conducting a literature review;(2)formulating the research questions;(3)ensuring that a case study is appropriate;(4)determining the type of case study design;(5)defining boundaries of the case(s)and selecting the case(s);(6)preparing for data collection;(7)collecting and organising the data;(8)analysing the data;(9)writing the case study report;and(10)appraising the quality.Case study research is a highly flexible and powerful research tool available to family medicine researchers for a variety of applications.

关键词： conducting preparing writing

Transcription control engineering and applications in synthetic biology

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Synthetic and Systems Biotechnology 2017年第3期2卷 176-191页

作者： michael D.Engstrom Brian f.Pfleger Genetics-Biotechnology Center University of Wisconsin-Madison School of Medicine and Public HealthUSA Department of Chemical and Biological Engineering University of Wisconsin-Madison College of EngineeringUSA Microbiology Doctoral Training Program University of Wisconsin-MadisonUSA

In synthetic biology,researchers assemble biological components in new ways to produce systems with practical applications.One of these practical applications is control of the flow of genetic information(from nucleic acid to protein),a.***.a.gene regulation.Regulation is critical for optimizing protein(and therefore activity)levels and the subsequent levels of metabolites and other cellular properties.The central dogma of molecular biology posits that information flow commences with transcription,and accordingly,regulatory tools targeting transcription have received the most attention in synthetic biology.In this mini-review,we highlight many past successes and summarize the lessons learned in developing tools for controlling transcription.In particular,we focus on engineering studies where promoters and transcription terminators(cis-factors)were directly engineered and/or isolated from DNA libraries.We also review several well-characterized transcription regulators(trans-factors),giving examples of how cis-and trans-acting factors have been combined to create digital and analogue switches for regulating transcription in response to various signals.Last,we provide examples of how engineered transcription control systems have been used in metabolic engineering and more complicated genetic circuits.While most of our mini-review focuses on the well-characterized bacterium Escherichia coli,we also provide several examples of the use of transcription control engineering in non-model organisms.Similar approaches have been applied outside the bacterial kingdom indicating that the lessons learned from bacterial studies may be generalized for other organisms.

关键词： Promoter Transcription Synthetic biology Bacteria Termination Metabolic engineering

Linking water and nutrients through the vadose zone: a fungal interface between the soil and plant systems

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Journal of Arid Land 2011年第3期3卷 155-163页

作者： michael f ALLEN Center for Conservation Biology University of California

Plant water availability, use, and management have largely focused on physical processes of infiltration and the role of roots in uptake and transpiration. However, roots and mycorrhizal fungi redistribute water in complex patterns. Here I describe some of our observations and experiments showing that mycorrhizal fungi play key roles in moving water for both transpiration and to facilitate nutrient acquisition under dry conditions. Mycorrhizal fungal hyphae grow from both surface and deep roots even into bedrock to help extract water under dry conditions. In both deep and surface roots, mycorrhizal fungi acquire water from pores too small for roots and root hairs to access, and at distances from roots and root hairs. Mycorrhizal fungi are also able to utilize hydraulic-lifted water from plants to obtain nutrients in extremely dry surface soils. The importance of these root symbionts in water and nutrient dynamics, and as integrators of surface and deeper water dynamics need further investigation.

关键词： mycorrhiza vadose zone hydraulic redistribution drought

RiPPing apart the rules for peptide natural products

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Synthetic and Systems Biotechnology 2018年第2期3卷 81-82页

作者： Aman S.Imani michael f.freeman Department of Biochemistry Molecular Biologyand Biophysics&BioTechnology InstituteUniversity of Minnesota-Twin CitiesSt.PaulMN 55108USA

Humankind has looked to peptide natural products as a source of valuable therapeutics harboring anti-cancer,immunomodulatory,and antibiotic properties since the discovery of penicillin in the late 1920s.Peptide natural products display a wide array of proteolytically resistant backbone modifications,non-canonical amino acids,and cyclizations that rigidify their structures and enable binding to specific cellular targets.Two distinct biosynthetic routes yield nearly all complex modified peptides currently identifieddthose incorporating amino acids via the ribosome and those that use multimodular protein complexes,termed non-ribosomal peptide synthetases(NRPSs),to ligate individual amino acids in an assembly-line fashion.Unlike ribosomal synthesis,NRPSderived peptides are not limited to the canonical 20 amino acids.NRPSs have been shown to incorporate upwards of 500 unique amino acids directly into their peptide scaffolds[1].The impressive amino acid building block repertoire of NRPS-derived peptides was thought to cover a much larger structural and chemical space compared to their ribosomally-derived counterparts.While ribosomally synthesized and post-translationally modified peptide(RiPP)pathways are currently known to introduce unique lanthionine thioether linkages and lasso peptide-like topologies[2]compared to NRPS pathways,for many years these examples were minor concessions to the breadth of distinct modifications only thought possible for non-ribosomal synthesis.But the(RiPP)tides are turning,and in dramatic fashion.

关键词： synthesis. canonical backbone

Update of cholangioscopy and biliary strictures

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World Journal of Gastroenterology 2011年第34期17卷 3864-3869页

作者： Marcus W Chin michael f Byrne Department of Gastroenterology and Hepatology Vancouver General Hospital Amy Athelstan Saw fellow University of Western AustraliaPerth 6009 Australia Department of Gastroenterology and Hepatology Vancouver General Hospital University of British ColumbiaVancouver V5Z1M9 Canada

Cholangioscopy remains another modality in the investigation of biliary strictures. At cholangioscopy, the"tumour vessel" sign is considered a specific sign formalignancy. Through its ability to not only visualisemucosa, but to take targeted biopsies, it has a greater accuracy, sensitivity and specificity for malignant strictures than endoscopic retrograde cholangiopancreatography guided cytopathological acquisition. Cholangioscopy however, is time consuming and costly, requires greater technical expertise, and should be reserved for the investigation of undifferentiated strictures after standard investigations have failed.

关键词：胆道狭窄敏感性胆管