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Twenty-nine million intrinsic Q-factor monolithic microresonators on thin-film lithium niobate

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Photonics Research 2024年第8期12卷 I0001-I0006页

作者： XInRUI ZHU YAOWEn HU SHEnGYUAn LU HAnA KWarnER XUDOnG LI YUnXIAnG SOnG LETÍCIA MAGALHÃES AMIRHASSAn SHAMS-AnSarI AnDREA CORDarO nEIL SInCLAIR MarKO LOnČar John A.Paulson School for Engineering and Applied Sciences Harvard UniversityCambridgeMassachusetts 02138USA State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China DRS Daylight Solutions San DiegoCalifornia 92127USA

The recent emergence of thin-film lithium niobate(TFLn)has extended the landscape of integrated *** has been enabled by the commercialization of TFLn wafers and advanced nanofabrication of TFLn such as high-quality dry ***,fabrication imperfections still limit the propagation loss to a few dB/m,restricting the impact of this ***,we demonstrate TFLn microresonators with a record-high intrinsic quality(Q)factor of twenty-nine million,corresponding to an ultra-low propagation loss of 1.3 dB/*** present spectral analysis and the statistical distribution of Q factors across different resonator *** work pushes the fabrication limits of TFLn photonics to achieve a Q factor within 1 order of magnitude of the material limit.

关键词： resonator lithium film

Quality-adjusted life years and surgical waiting list:Systematic review of the literature

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1155-1164页

作者： Roberto de la Plaza Llamas Lorena Ortega Azor Marina Hernández Yuste Ludovica Gorini Raquel aránzazu Latorre-Fragua Daniel Alejandro Díaz Candelas Farah Al Shwely Abduljabar Ignacio Antonio Gemio del Rey Department of General and Digestive Surgery Hospital Universitario de GuadalajaraGuadalajara 19002Spain Department of Surgery Medical and Social SciencesFaculty of Medicine and Health SciencesUniversity of AlcaláAlcaláde Henares 28871MadridSpain

BACKGROUnD The quality-adjusted life year(QALY)is a metric that is increasingly used today in the field of health economics to evaluate the value of different medical treatments and *** waiting lists(SWLs)represent a pressing problem in public *** QALY measure has rarely been used in the context of *** would be interesting to know how many QALYs are lost by patients on *** To investigate the relationship between QALYs and SWLs in a systematic review of the scientific *** The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** unlimited search was carried out in PubMed,updated on January 19,*** on the following variables were investigated and analyzed:Specialty,country of study,procedure under study,scale used to measure QALYs,the use of a theoretical or real-life model,objectives of the study and items measured,the economic value assigned to the QALY in the country in question,and the results and conclusions *** Forty-eight articles were selected for the *** data were found regarding QALYs lost on *** specialties in which QALYs were studied the most in relation to the waiting list were urology and general surgery,with 15 articles *** country in which the most studies of QALYs were carried out was the United States(n=21),followed by the United Kingdom(n=9)and Canada(n=7).The most studied procedure was organ transplantation(n=39),including 15 kidney,14 liver,5 heart,4 lung,and 1 ***(n=4),cataract surgery(n=2),bariatric surgery(n=1),mosaicplasty(n=1),and septoplasty(n=1)completed the surgical interventions ***-nine of the models used were theoretical(the most frequently applied being the Markov model,n=34),and nine were *** survey used to measure quality of life in 11 articles was the European Quality of Life-5 dimensions,but in 32 articles the survey was not specified.T

关键词： Quality-adjusted life year Waitlist Quality of life Surgery Systematic review

Journal of the American Heart Association|肝硬化退伍军人心肺血流动力学与病死率的关系:一项回顾性队列研究

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临床肝胆病杂志 2024年第6期40卷 1254-1254页

作者：杜佳霖温晓玉吉林大学第一医院肝胆胰内科

门脉性肺动脉高压(PoPH)与患者病死率增加相关,可能会限制肝脏疾病的治疗选择。目前缺乏与PoPH心肺血流动力学相关的临床风险连续性的数据。2024年4月,美国辛辛那提大学医学系Jose等探讨了肝硬化退伍军人心肺血流动力学与死亡率的关系。

关键词：肺血流动力学回顾性队列研究医学系门脉性肺动脉高压临床风险辛辛那提大学肝硬化病死率

Spatial analysis and structure of a cross-timber stand in the TallGrass Prairie Preserve (Pawhuska, Oklahoma)

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Journal of Forestry Research 2013年第1期24卷 47-52页

作者： José Ramón arévalo Departamento de Ecología Facultad de BiologíaUniversidad de La LagunaLa Laguna 38206Spain

I analyzed the spatial distribution and structure of trees in a cross timber forest in the Tallgrass Prairie Preserve （Pawhuska, Oklahoma, USA）. I mapped and measured diameter of all stems, saplings （〉1.5 m tall） and dead trees in a 4-ha plot. The stand was dominated by Quercus stellata and Q. marilandica. In total, I mapped 7,636 trees, consisting of 6,785 Q. stellata, 846 Q. marilandica, 2 Celtis occidentalis, 1 Fraxinus pensilvanica and 2 Prunus americana. For saplings, I mapped 54 Q. stellata and 21 Q. marilandica. The size class distribution of the two dominant species did not differ. The dominant mortality class was “standing dead”, while I only found saplings less than 2 m tall. The spatial distribution of the species indicated segregation in the use of the environment, generating a clumped univariate distribution of stems of the same species within radii of 30 m, but repulsion outside 30 m. This segregation can be explained by the different ecological requirements of each species.

关键词： conservation point pattern analysis Quercus stellata Q.marilandica size class distribution

Wettability,reactivity,and interface structure in Mg/ni system

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Journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka n.Sobczak Ł.Maj P.Darłak J.J.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the ni substrate(an average contact angleθnng and good wetting over the ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-ni alloys suggest a strong dissolution of ni in liquid Mg and apparent values of the final contact angles measured for the Mg/ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Conditioning of a Calcaric Soil with Biosolid and Compost Under Laboratory Conditions: Exploration of Soil Property Evolution

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Pedosphere 2019年第2期29卷 266-272页

作者： José Antonio GALán-PéREZ aránzazu PE?A Andalusian Institute for Earth Sciences Spanish National Research Council-University of Granada (CSIC-UGR)

Dear Editor,Conditioning of soils of low organic carbon(OC)is essential to establish optimal fertility conditions for the growth and development of future crops.A usual practice is the substrates of various origins,among which cheap wastes from agricultural or urban residues with high organic matter(OM)content have been gaining popularity in the last *** increase in soil OM is considered a desirable trait in agriculture because of its benefits.

关键词： Exploration Conditioning Laboratory

Alluvial sedimentation and tectonostratigraphic evolution in a narrow extensional zigzag basin margin (northern Teruel Basin, Spain)

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Journal of Palaeogeography 2019年第4期8卷 368-392页

作者： Lope Ezquerro aránzazu Luzón José L.Simón Carlos L.Liesa Departamento de Ciencias de la Tierra Facultad de Ciencias Geotransfer Research Group and Instituto de Investigación en Ciencias Ambientales (IUCA) Universidad de Zaragoza

The northern part of the eastern margin of the extensional neogene Teruel Basin(central-eastern Spain)consists of a non-linear,zigzag fault zone made of alternating ca.2 km long,nnW-SSE trending segments and shorter nnESSW *** outcrop conditions made possible a comprehensive integrated stratigraphic and structural study,especially focused on coarse clastic sediments deposited along the basin ***-exposed stratal relationships with boundary faults,allowed the analysis of tectonic influence on *** deformation includes growth faulting,rollover anticlines,and monoclines and associated onlap stratal terminations,angular unconformities,and other complex growth strata *** of them is the onlap-over-rollover bed arrangement described here for the first time,which reveals the competition between tectonic subsidence and sedimentary ***,the structural inheritance(dense Mesozoic fracture grid)and the dominant,nearly‘multidirectional’(σ1 vertical,σ2≈σ3),Pliocene extensional regime withσ3 close to E-W,are considered to have controlled the margin structure and ***-stratigraphic evolution includes:(i)reactivation of inherited nnW-SSE faults and development of W-SW-directed small alluvial fans(SAF)while nnE-SSW segments acted as gentle relay ramp zones;(ii)progressive activation of nnE-SSW faults and development of nW-directed very small alluvial fans(VSAF);during stages i and ii sediments were trapped close to the margin,avoiding widespread progradation;(iii)linking of nnW-SSE and nnE-SSW structural segments,overall basin sinking and widespread alluvial progradation;(iv)fault activity attenuation and alluvial *** particular structure and kinematic evolution of this margin controlled alluvial system *** of alluvial fans,directly set up at the border faults,was conditioned by the narrowness of the margin,small catchment areas,and proximity between faults,which prevented the development of l

关键词： Extensional basin Alluvial fan Stratal stacking pattern Structural inheritance Fault linkage

Versatile synthesis of cadalene and iso-cadalene from himachalene mixtures:Evidence and application of unprecedented rearrangements

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Chinese Chemical Letters 2020年第7期31卷 1851-1854页

作者： Mustapha Ait El had Abdelouahd Oukhrib Mohamed Zaki Martine Urrutigoity Ahmed Benharref Remi Chauvin Laboratoire de Chimie Biomoleculaire Substances Naturelies et Reactivite(URAC 16)Faculte des Sciences SemlaliaUniversite Cadi AyyadB.P.2390MarrakechMorocco CnRS LCC(Laboratoire de Chimie de Coordination)BP 4409931077Toulouse Cedex 4France InP-EnSIACET 4 allee Emile Monso31030Toulouse CedexFrance Universite de Toulouse UPSICT-FR 259931062Toulouse Cedex 9France

From a mixture of α-,β-and y-himachalenes extracted from waste wood of Atlas cedar(Cedrus atlantica),cadalene(1,6-dimethyl-4-isopropylnaphthalene)and iso-cadalene(1,6-dimethyl-3-isopropylnaphthalene)were produced in two steps with up to 71%±5%yield through the ar-himachalene intermediate using I2 and/or AlCl3 as *** selectivity is shown to sharply depend on the operating conditions:while I2/AlCl3 in dichloromethane promotes the formation of cadalene,the formation of iso-cadalene is favored in the presence of AlCl3 in *** bicyclic aromatic compounds were thus obtained through unique rearrangements involving sequential C—C bond cleavage/fo rmation and hydride transfer *** the absence of AlCl3 or I2,dihydrocurcumene was also found to be formed with up to 70%selectivity.A tentative mechanism is proposed and discussed.

关键词： aromatic reactivity Cadalenes Dihydrocurcumene Himachalenes Rearrangements

A Crystallization Study of nanocrystalline PZT 53/47 Granular arrays Using a Sol-Gel Based Precursor

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Journal of Materials Science & Technology 2011年第6期27卷 489-496页

作者： A.Surez-Gómez J.M.Saniger-Blesa F.Calderón-Pinar CCADET-Universidad nacional Autónoma de México Cd.UniversitariaCirc.Exterior s/nA.P.70-186Coyoacn 04510México D.F.México Laboratorio de Ingeniería Electroquímica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoCd.UniversitariaCoyoacn 04510México D.F.México Facultad de Física/IMRE San Lzaro y LUniversidad de la Habana

In this work,we intend to perform a detailed study on the crystallization process of PZT 53/47 nanostructured powders by starting out with an amorphous precursor synthesized by a sol-gel based *** interests also lie in the feasibility for controlling the average grain size of the final structure in the submicron range on an ab initio ***,Fourier transform infrared spectroscopy（FT-IR）,Raman（Stokes and Anti-Stokes）,X-ray diffraction（XRD） and scanning electron microscopy（SEM） are used to examine the microstructural characteristics based on previously reported differential thermal analysis/thermal gravimetric analysis（DTA/TGA） *** results show a crystallization temperature of 800℃ to attain pure perovskite phase with excellent morphological quality,average grain size 〈DG〉〈 300 nm and with average crystallite size 〈DC〉〈15 nm.

关键词： Powders-chemical preparation PZT synthesis Sol-gel precursors Microstructure- final Vibrational spectroscopies X-ray diffraction