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Modular architecture for fully non-blocking silicon photonic switch fabric

Microsystems & Nanoengineering 2017年第1期3卷 430-438页

作者： Dessislava Nikolova David M.calhoun Yang Liu Sébastien Rumley Ari Novack tom Baehr-Jones Michael Hochberg Keren Bergman Department of Electrical Engineering Columbia University530 West 120th StreetNew YorkNY 10027USA coriant Advanced Technology Group 171 Madison AvenueNew YorkNY 10016USA

Integrated photonics offers the possibility of compact,low energy,bandwidth-dense interconnects for large port count spatial optical switches,facilitating flexible and energy efficient data movement in future data communications *** achieve widespread adoption,intimate integration with electronics has to be possible,requiring switch design using standard microelectronic foundry processes and available *** report on the feasibility of a switch fabric comprised of ubiquitous silicon photonic building blocks,opening the possibility to combine technologies,and materials towards a new path for switch fabric *** than focus on integrating all devices on a single silicon chip die to achieve large port count optical switching,this work shifts the focus towards innovative packaging and integration *** this work,we demonstrate 1×8 and 8×1 microring-based silicon photonic switch building blocks with software control,providing the feasibility of a full 8×8 architecture composed of silicon photonic building *** proposed switch is fully non-blocking,has path-independent insertion loss,low crosstalk,and is straightforward to *** further analyze this architecture and compare it with other common switching architectures for varying underlying technologies and radices,showing that the proposed architecture favorably scales to very large port counts when considering both crosstalk and architectural *** a switch fabric into functional building blocks via multiple photonic integrated circuits offers the advantage of piece-wise manufacturing,packaging,and assembly,potentially reducing the number of optical I/O and electrical contacts on a single die.

关键词： data communications optical switching silicon photonics

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Synthesis of an IS and Steviol Glycoside Analysis by a Validated Internal Standard Method

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American Journal of Analytical chemistry 2018年第11期9卷 547-559页

作者： Jan M. c. Geuns tom Struyf Stijn ceunen Gert Steurs Wim De Borggraeve Laboratory of Functional Biology KU Leuven Leuven Belgium Division of Molecular Design and Synthesis KU Leuven Leuven Belgium

The internal standard (IS) method is the best method for the analysis of samples, as it is independent of errors in injection volume, changes in sample volumes, and changes in sensitivity of the detector, etc. Use of an internal standard allows for the correction of losses due to sample clean-up of complex samples. An ideal IS is a compound that has properties very similar to, and that behaves as the compounds to be analysed. Ideally, only in the last step of analysis (HPLc), the IS should be well separated from the compounds of the mixture to be analysed. After testing several existing compounds with negative results, we decided to synthesise the 19-O-β-D-galactopyranosyl-13-O-β-D-glucopyranosyl-steviol as IS. This is the 19-galactosyl ester of steviolmonoside (13-O-β-D-glucopyranosyl-steviol). The IS was made according to published methods. Steviolmonoside (SM) was made from purified commercial rubusoside (Rub) by refluxing it in 10% KOH for 2 h. SM was precipitated and crystallized from MeOH. The hydroxyls of the glucose unit of SM were protected by acetylation. The acetylated SM was crystallized from acetone and dissolved in 1,2-dichloroethane. Then Ag2cO3 on celite and tetra-acetylated galactopyranosyl bromide were added and the mixture was refluxed for 2 h. After cooling, BaO in MeOH was added to remove the acetyl groups. The 1,2-dichloroethane fraction was then extracted three times with equal volumes of water and the water fraction containing the IS was further purified on a c18 flash chromatography column. Traces of unreacted SM were removed by preparative HPLc on an Alltima c18 column (250 mm × 22 mm, particle size 10 μm) with AccN:water (35:65, 20 ml/min). Detection was at 210 nm (KNAUER, “Smartline” UV detector 2500). The collected IS fraction from the HPLc was completely dried. Mixtures of steviol glycosides (SVglys) containing IS could be purified over SPE cartridges without change of the SVgly over IS ratio. The calibration curves for rebaudioside A (

关键词： Steviol Glycosides Internal Standard Method Validation Quantification Purification

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cochrane关于人乳头状瘤病毒疫苗的综述欠完善,而且忽视了重要的偏倚证据

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英国医学杂志中文版 2019年第1期22卷 49-53页

作者： Lars Jcrgensen Peter c Gotzsehe tom Jefferson 赵静(译) 王淑珍(校) Nordie coehrane centre Rigshospitalet (dept. 7811)Copenhagen Denmark centre for Evidence Based Medicine University of Oxford OxfordUK 首都医科大学附属北京朝阳医院妇产科

2018年5月,cochrane循证医学协作网发表了关于人乳头状瘤病毒(HPV)疫苗的综述1。该篇综述主要评估了HPV疫苗对宫颈癌癌前病变的预防作用。cochrane对综述的要求一贯是很高的。,但这篇关于HPV疫苗的综述却存在着严重的缺陷,本文将针对这... 详细信息

2018年5月,cochrane循证医学协作网发表了关于人乳头状瘤病毒(HPV)疫苗的综述1。该篇综述主要评估了HPV疫苗对宫颈癌癌前病变的预防作用。cochrane对综述的要求一贯是很高的。,但这篇关于HPV疫苗的综述却存在着严重的缺陷,本文将针对这篇综述的局限性进行讨论。

关键词： cochrane 人乳头状瘤病毒病毒疫苗综述 HPV疫苗证据偏倚循证医学

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Transjugular intrahepatic portosystemic shunt-placement increases arginine/asymmetric dimethylarginine ratio in cirrhotic patients

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World Journal of Gastroenterology 2008年第47期14卷 7214-7219页

作者： Michiel Pc Siroen Reiner Wiest Milan c Richir tom Teerlink Jan A Rauwerda Friedrich T Drescher Niels Zorger Paul AM van Leeuwen Department of Surgery VU University Medical CenterAmsterdam 1007 MBThe Netherlands Department of Internal Medicine University HospitalRegensburg D-93042Germany Department of clinical chemistry VU University Medical CenterAmsterdam 1007 MBThe Netherlands Department of Radiology University HospitalRegensburg D-93042Germany

AIM:To analyze the change of dimethylarginine plasma levels in cirrhotic patients receiving transjugular intrahepatic portosystemic shunt(TIPS).METHODS:To determine arginine,asymmetric dimethylarginine(ADMA),symmetric dimethylarginine(SDMA),and nitric oxide(NO) plasma levels,blood samples were collected from the superior cava,hepatic,and portal vein just before,directly after,and 3 mo after ***:A significant increase in the arginine/ADMA ratio after TIPS placement was ***,TIPS placement enhanced renal function and thereby decreased systemic SDMA *** patients with renal dysfunction before TIPS placement,both the arginine/ADMA ratio and creatinine clearance rate increased significantly,while this was not the case in patients with normal renal function before TIPS *** function did not change significantly after TIPS placement and no significant decline in ADMA plasma levels was ***:The increase of the arginine/ADMA ratio after TIPS placement suggests an increase in intracellular NO *** addition,this study suggests that TIPS placement does not alter dimethylarginine dimethylaminohydrolase(DDAH) activity and confirms the major role of the liver as an ADMA clearing organ.

关键词： Asymmetric dimethylarginine Symmetricdimethylarginine Arginine Liver cirrhosis Transjugularintrahepatic portosystemic shunt

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Plasmon-induced trap filling at grain boundaries in perovskite solar cells

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Light(Science & Applications) 2021年第11期10卷 2233-2244页

作者： Kai Yao Siqi Li Zhiliang Liu Yiran Ying Petr Dvořák Linfeng Fei tomášŠikola Haitao Huang Peter Nordlander Alex K-Y.Jen Dangyuan Lei Institute of Photovoltaics/Department of Materials Science and Engineering Nanchang UniversityNanchang330031China Department of Applied Physics The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Institute of Physical Engineering Brno University of TechnologyTechnická2Brno61669Czech Republic Laboratory for Nanophotonics Department of Physics and AstronomyDepartment of Electrical and Computer EngineeringRice UniversityHoustonTexas77005USA

The deep-level traps induced by charged defects at the grain boundaries(GBs)of polycrystalline organic-inorganic halide perovskite(OIHP)films serve as major recombination centres,which limit the device ***,we incorporate specially designed poly(3-aminothiophenol)-coated gold(Au@PAT)nanoparticles into the perovskite absorber,in order to examine the influence of plasmonic resonance on carrier dynamics in perovskite solar *** changes in the photophysical properties of the OIHP films reveal that plasmon excitation could fill trap sites at the GB region through photo-brightening,whereas transient absorption spectroscopy and density functional theory calculations correlate this photo-brightening of trap states with plasmon-induced interfacial *** a result,the device achieved the best efficiency of 22.0%with robust operational *** work provides unambiguous evidence for plasmon-induced trap occupation in OIHP and reveals that plasmonic nanostructures may be one type of efficient additives to overcome the recombination losses in perovskite solar cells and thin-film solar cells in general.

关键词： perovskite grain absorber

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From leaf to whole-plant water use efficiency(WUE)in complex canopies:Limitations of leaf WUE as a selection target

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The crop Journal 2015年第3期3卷 220-228页

作者： Hipólito Medrano Magdalena tomás Sebastià Martorell aume Flexas Esther Hernández Joan Rosselló Alicia Pou José-Mariano Escalona Josefina Bota Research Group on Plant Biology under Mediterranean conditions Department of Biology IMEDEA (CSIC-Universitat de les Illes Balears)Carretera de Valldemossa km 7.5 07122 Palma de Mallorca Spain Institute of Life Science Catholic University of Louvain Place de l'Université 1 B-1348 Louvain-la-Neuve Belgium

Plant water use efficiency(WUE) is becoming a key issue in semiarid areas, where crop production relies on the use of large volumes of water. Improving WUE is necessary for securing environmental sustainability of food production in these areas. Given that climate change predictions include increases in temperature and drought in semiarid regions,improving crop WUE is mandatory for global food production. WUE is commonly measured at the leaf level, because portable equipment for measuring leaf gas exchange rates facilitates the simultaneous measurement of photosynthesis and transpiration. However,when those measurements are compared with daily integrals or whole-plant estimates of WUE, the two sometimes do not agree. Scaling up from single-leaf to whole-plant WUE was tested in grapevines in different experiments by comparison of daily integrals of instantaneous water use efficiency [ratio between cO2assimilation(AN) and transpiration(E); AN/E] with midday AN/E measurements, showing a low correlation, being worse with increasing water stress. We sought to evaluate the importance of spatial and temporal variation in carbon and water balances at the leaf and plant levels. The leaf position(governing average light interception) in the canopy showed a marked effect on instantaneous and daily integrals of leaf WUE. Night transpiration and respiration rates were also evaluated, as well as respiration contributions to total carbon balance. Two main components were identified as filling the gap between leaf and whole plant WUE: the large effect of leaf position on daily carbon gain and water loss and the large flux of carbon losses by dark respiration. These results show that WUE evaluation among genotypes or treatments needs to be revised.

关键词： Water use Drought Intrinsic water use efficiency 13c Instantaneous water use efficiency Whole plant water use efficiency

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Anisotropic magnetoelastic response in the magnetic Weyl semimetal co_(3)Sn_(2)S_(2)

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Science china(Physics,Mechanics & Astronomy) 2021年第5期64卷 82-90页

作者： chang Liu changJiang Yi XingYu Wang JianLei Shen Tao Xie Lin Yang tom Fenne Uwe Stuhr ShiLiang Li HongMing Weng YouGuo Shi EnKe Liu HuiQian Luo Beijing National Laboratory for condensed Matter Physics Institute of PhysiesChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBejing 100190China Laboratory for Neutron Scattering and Imaging Paul Scherrer InstituteVlligen CH-5232Switzerland Songshan Lake Materials Laboratory Dongguan 523808China ScAS centre for Excelence in Topological Quantum computation Bejing 100190China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101400China

co_(3)Sn_(2)S_(2) is a recently identified magnetic Weyl semimetal in Shandite compounds. Upon cooling, co_(3)Sn_(2)S_(2) undergoes a ferromagnetic transition with c-axis polarized moments(0.3 μ_(B)/co) around T_(c)= 175 K, followed by another magnetic anomaly around T_(A)≈ 140 K. A large intrinsic anomalous Hall effect is observed in the magnetic state below Tc with a maximum of anomalous Hall angle near T_(A). Here, we report an elastic neutron scattering on the crystalline lattice of co_(3)Sn_(2)S_(2) in a magnetic field up to 10 T. A strongly anisotropic magnetoelastic response is observed, while only a slight enhancement of the Bragg peaks is observed when B//c. The in-plane magnetic field(B//ab) dramatically suppresses the Bragg peak intensity probably by tilting the moments and lattice toward the external field direction. The in-plane magnetoelastic response commences from T_(c), and as it is further strengthened below T_(A), it becomes nonmonotonic against the field between T_(A) and T_(c) because of the competition from another in-plane magnetic order. These results suggest that a magnetic field can be employed to tune the co_(3)Sn_(2)S_(2) lattice and its related topological states.

关键词： Weyl semimetal magneto-elastic coupling topological materials elastic neutron scattering ferromagnetism

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Dispersion of neutron spin resonance mode in Ba0.67K0.33Fe2As2

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chinese Physics B 2021年第12期30卷 605-610页

作者：谢涛刘畅 tom Fennell Uwe Stuhr 李世亮罗会仟 Beijing National Laboratory for condensed Matter Physics Institute of PhysicsChinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Neutron Scattering Division Oak Ridge National Laboratory Laboratory for Neutron Scattering and Imaging Paul Scherrer Institut Songshan Lake Materials Laboratory

We report an inelastic neutron scattering investigation on the spin resonance mode in the optimally hole-doped ironbased superconductor Ba0.67K0.33Fe2As2with Tc= 38.2 K. Although the resonance is nearly two-dimensional with peak energy ER ≈14 meV, it splits into two incommensurate peaks along the longitudinal direction([H, 0, 0]) and shows an upward dispersion persisting to 26 meV. Such dispersion breaks through the limit of total superconducting gaps ?tot= |?k| + |?k+Q|(about 11–17 meV) on nested Fermi surfaces measured by high resolution angle resolved photoemission spectroscopy(ARPES). These results cannot be fully understood by the magnetic exciton scenario under s±-pairing symmetry of superconductivity, and suggest that the spin resonance may not be restricted by the superconducting gaps in the multi-band systems.

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Windows 98编程实用大全

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丛书名：万水计算机技术实用大全系列

1999年

作者：（美）（R.c.莱内克）Richard c.Leinecker （美）（T.阿彻）tom Archer 齐舒创作室译

来源：畅想之星图书光盘版（南... 评论

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Surface brightens up Si quantum dots: direct bandgap-like size-tunable emission

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Light(Science & Applications) 2013年第1期2卷 242-247页

作者： Katerina Dohnalova Alexander N Poddubny Alexei A Prokofiev Wieteke DAM de Boer chinnaswamy P Umesh Jos MJ Paulusse Han Zuilhof tom Gregorkiewicz Van der Waals-Zeeman Institute University of AmsterdamNL-1098 XH AmsterdamThe Netherlands Laboratory of Organic chemistry Wageningen University6703 HB WageningenThe Netherlands Department of chemical and Materials Engineering King Abdulaziz UniversityJeddahSaudi Arabia Ioffe Physical-Technical Institute RAS 26 Polytechnicheskaya194021 Saint-PetersburgRussia current address:MIRA Institute Department of Biomedical ChemistryUniversity of TwenteBuilding Zuidhorst EnschedeThe Netherlands

colloidal semiconductor quantum dots(QDs)constitute a perfect material for ink-jet printable large area displays,photovoltaics,light-emitting diode,bio-imaging luminescent markers and many other *** this purpose,efficient light emission/absorption and spectral tunability are necessary *** are currently fulfilled by the direct bandgap ***-QDs could offer the solution to major hurdles posed by these materials,namely,toxicity(e.g.,cd-,Pb-or As-based QDs),scarcity(e.g.,QD with In,Se,Te)and/or *** we show that by combining quantum confinement with dedicated surface engineering,the biggest drawback of Si—the indirect bandgap nature—can be overcome,and a‘direct bandgap’variety of Si-QDs is *** demonstrate this transformation on chemically synthesized Si-QDs using state-of-the-art optical spectroscopy and theoretical *** carbon surface termination gives rise to drastic modification in electron and hole wavefunctions and radiative transitions between the lowest excited states of electron and hole attain‘direct bandgap-like’(phonon-less)*** results in efficient fast emission,tunable within the visible spectral range by QD *** findings are fully justified within a tight-binding theoretical *** the c surface termination is replaced by oxygen,the emission is converted into the well-known red luminescence,with microsecond decay and limited spectral *** that way,the‘direct bandgap’Si-QDs convert into the‘traditional’indirect bandgap form,thoroughly investigated in the past.

关键词： direct bandgap optical spectroscopy optoelectronics organic capping silicon quantum dots tight binding model

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