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nanophotonics and negative ε materials

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第1期7卷 41-44页

作者： THYLén lars BERGLInD Eilert Department of Microelectronics and Information Technology Royal Institute of Technology 164 40 Stockholm Sweden Kista Photonics Research Center 164 40 Stockholm Sweden Joint Research Center of Photonics of the Royal Institute of Technology Stockholm Sweden and Zhejiang University Hangzhou 310027 China Department of Microelectronics and Information Technology Royal Institute of Technology 164 40 Stockholm Sweden Kista Photonics Research Center 164 40 Stockholm Sweden

The feasibility of using metal optics or negative ε materials, with the aim of reducing the transversal extent of waveguided photonic fields to values much less than the vacuum wavelength, in order to achieve significantly higher densities of integration in integrated photonics circuits that is possible today is discussed. Relevant figures of merit are formulated to this end and used to achieve good performance of devices with today＇s materials and to define required improvements in materials characteristics in terms of decreased scattering rates in the Drude model. The general conclusion is that some metal based circuits are feasible with today＇s matals. Frequency selective metal devices will have Q values on the order of only 10-100, and significant improvements of scattering rates or lowering of the imaginary part of e have to be achieved to implement narrowband devices. A photonic ＂Moore＇s law＂ of integration densities is proposed and exemplified.

关键词： Integrated optics circuit Optical surface wave Optical waveguide Microwave circuit Waveguide

Gorenstein dimensions of unbounded complexes and change of base (with an appendix by Driss Bennis)

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Science China Mathematics 2017年第3期60卷 401-420页

作者： CHRISTEnSEn lars Winthe KOKSAL Fatih LIAnG Li Department of Mathematics and Statistics Texas Tech University Lubbock TX 79409 USA Department of Computer and Mathematical Sciences Lewis University Romeoville IL 60446 USA School of Mathematics and Physics Lanzhou Jiaotong University Lanzhou 730070 China

For a commutative ring R and a faithfully fiat R-algebra S we prove, under mild extra assumptions, that an R-module M is Gorenstein flat if and only if the left S-module S R M is Gorenstein flat, and that an R-module n is Gorenstein injective if and only if it is cotorsion and the left S-module Homn（S, n） is Gorenstein injective. We apply these results to the study of Gorenstein homological dimensions of unbounded complexes. In particular, we prove two theorems on stability of these dimensions under faithfully flat （co-）base change.

关键词： Gorenstein injective dimension faithfully flat co-base change Corenstein flat dimension faithfullyflat base change

Adaptive-optical 3D microscopy for microfluidic multiphase flows

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Light(Advanced Manufacturing) 2024年第3期5卷 105-119页

作者： Clemens Bilsing Erik nützenadel Sebastian Burgmann Jürgen Czarske lars Büttner Laboratory of Measurement and Sensor System Techniques TUD Dresden University of Technology01069 DresdenGermany Chair of Fluid Mechanics Bergische Universitát Wuppertal42119 WuppertalGermany BIOLAS Laboratory of Measurement and Sensor System Techniques01069 DresdenGermany

Measurements based on optical microscopy can be severely impaired if the access exhibits variations of the refractive *** the case of fluctuating liquid-gas boundaries,refraction introduces dynamical aberrations that increase the measurement *** is prevalent at multiphase flows(***,film flows)that occur in many technical applications as for example in coating and cleaning processes and the water management in fuel *** this paper,we present a novel approach based on adaptive optics for correcting the dynamical aberrations in real time and thus reducing the measurement *** shape of the fluctuating water-air interface is sampled with a reflecting light beam(Fresnel Guide Star)and a Hartmann-Shack sensor which makes it possible to correct its influence with a deformable mirror in a closed ***-dimensional flow measurements are achieved by using a double-helix point spread *** measure the flow inside a sessile,oscillating 50-μl droplet on an opaque gas diffusion layer for fuel cells and show that the temporally varying refraction at the droplet surface causes a systematic underestimation of the flow field magnitude corresponding to the first droplet eigenmode which plays a major role in their detachment *** demonstrate that the adaptive optics correction is able to reduce this systematic ***,the adaptive optics system can pave the way to a deeper understanding of water droplet formation and detachment which can help to improve the efficiency of fuels cells.

关键词： Double-Helix point spread function Adaptive optics Particle tracking velocimetry Aberration correction Depth-resolving microscopy Closed-loop control

Lost Memories of Winter： Breaking the FLC Silence

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Molecular Plant 2017年第12期10卷 1477-1479页

作者： Miyuki nakamura Iva Mozgova lars Hennig Department of Plant Biology Uppsala BioCenter Swedish University of Agricultural Sciences and Linnean Center for Plant Biology 75007 Uppsala Sweden Institute of Microbiology of the Czech Academy of Sciences Centre Algatech Opatovický mlýn 37981 Třeboň Czech Republic Faculty of Science University of South Bohemia in Ceske Budejovice 37005 Ceske Budejovice Czech Republic

Vernalization, the acquisition of competence to flower after extended cold treatment, has puzzled researchers throughout the last century. Great progress in understanding the molecular mechanisms of vernalization in Arabidopsis has been made in the course of the last 20 years, placing the flowering repressor- encoding gene FLOWERInG LOCUS C （FLC） in the limelight （Bouch6 et al., 2017）. In vernalization-dependent accessions, FRIGIDA （FRI） ensures strong expression of FLC that delays flowering, and extended exposure to low temperatures such as during winter leads to stable repression of FLC, which in turn clears the way for induction of flowering.

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Innovation in geoprocessing for a Digital Earth

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International Journal of Digital Earth 2018年第1期11卷 3-6页

作者： Barbara Hofer Carlos Granell lars Bernard Interfaculty Department of Geoinformatics-Z_GIS University of SalzburgSalzburgAustria Geospatial Technologies Research Group(GEOTEC) Universitat Jaume ICastellón de la PlanaSpain Chair of Geoinformatics Technische Universität DresdenDresdenGermany

Online geoprocessing,the provision and the use of spatial analysis functionality on the Web,is a powerful technological approach to fully realise the vision of a Digital *** Digital Earth objectives include the integration of information across diverse domains in order to address environmental and societal challenges as well as the interactive and exploratory provision of information to a wide audience(Craglia et al.2008).

关键词： interactive Earth Web

Hydrological Responses and Flow Pathways in an Acrisol on a Forested Hillslope with a Monsoonal Subtropical Climate

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Pedosphere 2017年第6期27卷 1037-1048页

作者： lars-Erik SORBOTTEn Jannes STOLTE WAnG Yanhui Jan MULDER norconsult AS N-1338 Sandvika(Norway) norwegian Institute of Bioeconomy Research(nIBIO) N-1430 Aas(Norway) Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091(China) Department of Environmental Sciences Norwegian University of Life SciencesN-1432 Aas(Norway)

The nature of subsurface flow depends largely on hydraulic conductivity of the vadoze zone, permeability of the underlying bedrock, existence of soil layers differing in hydraulic properties and macropore content, soil depth, and slope *** of flow pathways on forested hillslopes is essential to understand hydrological dynamics and solute transport ***, with their argic Bt horizons, are challenging in this *** further elucidate flow pathways of water and short-term variability of soil moisture patterns in Acrisols, a field study was conducted on a forested hillslope in a sub-catchment of the Tie Shan Ping(TSP)watershed, 25 km northeast of Chongqing City, *** catchment is covered by a mixed secondary forest dominated by Masson pine(Pinus massoniana).Soil saturated hydraulic conductivity(K sat) was significantly reduced at the interface between the AB and Bt horizons(2.6 × 10^(-5) vs.1.2 × 10^(-6) m s^(-1)), which led to that the flow volume generated in the Bt horizon was of little quantitative importance compared to that in the AB *** was a marked decrease in porosity between the OA and AB horizons, with a further decrease deeper in the mineral ***, the content of soil pores > 300 μm was higher in the AB horizon(14.3%)than in the Bt horizon(6.5%).This explained the difference in soil K sat *** study showed that Bt horizon had limited water transport capability, forcing part of the infiltrated rainwater as interflow through the OA and AB ***, the topsoil responded quickly to rainfall events, causing frequent cycles of saturation and aeration of soil pores.

关键词： dye tracer hillslope hydrology hydraulic conductivity preferential flow soil pores subsurface lateral flow

Endoscopic retrograde cholangiopancreatography with rendezvous cannulation reduces pancreatic injury

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World Journal of Gastroenterology 2013年第36期19卷 6026-6034页

作者： Fredrik Swahn Sara Regnér lars Enochsson lars Lundell Johan Permert Magnus nilsson Henrik Thorlacius Urban Arnelo Division of Surgery Department of Clinical Science Intervention and TechnologyKarolinska Institutet Department of Surgical Gastroenterology Karolinska University Hospital Department of Clinical Science Lund University Skne University Hospital Department of Surgery Skne University Hospital

AIM:To examine whether rendezvous endoscopic retrograde cholangiopancreatography(ERCP)is associated with less pancreatic damage,measured as leakage of proenzymes,than conventional ***:Patients(n=122)with symptomatic gallstone disease,intact papilla and no ongoing inflammation,were prospectively enrolled in this case-controldesigned ***-one patients were subjected to laparoscopic cholecystectomy and if intraoperative cholangiography suggested common bile duct stones(CBDS),rendezvous ERCP was performed intraoperatively(n=40).Patients with a negative cholangiogram constituted the control group(n=41).Another 41 patients with CBDS,not subjected to surgery,underwent conventional *** proenzymes,procarboxypeptidase B and trypsinogen-2 levels in plasma,were analysed at 0,4,8 and 24 *** proenzymes were determined in-house with a double-antibody enzyme linked immunosorbent *** amylase was measured by an enzymatic colourimetric modular analyser with the manufacturer’s *** samples were blinded at ***:Post ERCP pancreatitis(PEP)occurred in3/41(7%)of the patients cannulated with conventional ERCP and none in the rendezvous *** serum levels indicating pancreatic leakage were significantly higher in the conventional ERCP group compared with the rendezvous ERCP group regarding pancreatic amylase levels in the 4-and 8-h samples(P=0.0015;P=0.03),procarboxypeptidase B in the4-and 8-h samples(Pnd trypsinogen-2 in the 24-hour samples(P=0.03).no differences in these markers were observed in patients treated with rendezvous cannulation technique compared with patients that underwent cholecystectomy alone(control group).Post procedural concentrations of pancreatic amylase and procarboxypeptidase B were significantly correlated with pancreatic duct cannulation and ***:Rendezvous ERCP reduces pancreatic enzyme leakage compared with conventional ERCP cannulation ***,l

关键词： Common bile duct stones Procarboxypeptidase B Trypsinogen-2 Pancreatic amylase Intraoperative endoscopic retrograde cholangiopancreatography

Reduced peripheral vascular reactivity in refractory angina pectoris:Effect of enhanced external counterpulsation

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Journal of Geriatric Cardiology 2011年第4期8卷 215-223页

作者： Susanne M Bondesson Marie-Louise Edvinsson Thomas Pettersson lars Edvinsson Department of Medicine Kristianstad HospitalSE-29185 KristianstadSweden Department of Health Sciences Lund Lund UniversitySE-22100 LundSweden Department of Emergency Medicine Lund University HospitalSE-22185 LundSweden

Objective To examine if the skin microvascular bed is altered and can be modified by enhanced external counterpulsation(EECP)in patients with chronic refractory *** Twenty patients diagnosed with refractory angina were divided into EECP(n=10)or no EECP(n=10)*** data were compared to matched healthy subjects(n=20).The cutaneous forearm microvascular blood flow was measured by Laser-Doppler *** vascular responsiveness to iontophoretic administration of acetylcholine(ACh),sodium nitroprusside(SnP)and local skin warming were *** of Canadian Cardiovascular Society(CCS)-class,blood pressure and plasma samples were *** EECP patients showed reduced CCS-class compared to no EECP(Pnd no EECP(Pne(Pno difference in resting blood flow between the two refractory groups at baseline as well as after EECP and seven weeks of *** to heating,the responses to ACh and SnP in the cutaneous microcirculation were lower in both groups of refractory angina patients as compared to healthy subjects(Pnts corresponded positively to the treatment shown by reduced plasma level of soluble interleukin-2 receptor and *** Refractory angina patients have reduced responsiveness in their cutaneous microcirculation to ACh,SnP and heat compared to healthy *** EECP reduced the CCS-class,this effect was not associated with improvements in responsiveness of the cutaneous microcirculation.

关键词： refractory angina pectoris flowmetry microcirculation enhanced external counterpulsation

Electrochemical probing into the active sites of graphitic-layer encapsulated iron oxygen reduction reaction electrocatalysts

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Science Bulletin 2018年第1期63卷 24-30页

作者： Lijie Zhong Jens Oluf Jensen lars.nilausen Cleemann Chao Pan Qingfeng Li Department of Energy Conversion and Storage Technical University of Denmark

The graphitic-layer encapsulated iron-containing nanoparticles(G@Fe) have been proposed as a potential type of active and stable non-precious metal electrocatalysts(nPMCs) for the oxygen reduction reaction(ORR). However, the contribution of the encapsulated components to the ORR activity is still unclear compared with the well-recognized surface coordinated Fen_x/C structure. Using the strong complexing effect of the iron component with anions, cyanide(Cn^-) in alkaline and thiocyanate(SCn^-) in acidic media, the metal containing active sites are electrochemically probed. Three representative catalysts are chosen for a comparison including the as-prepared encapsulated G@Fe, commercial Fe/n/C catalyst with iron–nitrogen coordinated surface functionalities and molecular iron phthalocyanine(Fe Pc) containing well-defined structures and compositions. It was found that all samples showed significant shifts of half-wave potentials indicating that surface Fe coordinated sites in all cases. The G@Fe catalyst showed the weakest poisoning effect(the lowest shifts of half-wave potential) compared to the Fe/n/C and Fe Pc catalysts in both electrolytes. These results could be explained that the encapsulated iron components influence the Fen_x/C and/or n_xC surface functionality.

关键词： Encapsulated Fe catalysts Oxygen reduction reaction Ion poisoning Active sites nPMCs