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Coherent OnU based on 850 μm-long cavity-RSOA for next-generation ultra-dense access network

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Chinese Optics Letters 2016年第5期14卷 19-23页

作者： Guang Yong Chu Adolfo Lerín iv.n n.Cano Victor Polo Josep Prat Department of Signal Theory and Communications Universitat Politècnica de Catalunya

In this Letter, an efficient bidirectional differential phase-shift keying （DPSK）--DPSK transmission for a ultra- dense wavelength division-multiplexed passive optical network is proposed. A single distributed feedback laser at the optical network unit （OnU） is used both as the local laser for downlink coherent detection and the optical carrier for uplink. Phase-shift keying is generated using a low-cost reflective semiconductor optical amplifier （RSOA） at the OnU. The RSOA chip has the bandwidth of 4.7 GHz at the maximum input power and bias current. For uplink transmission, the sensitivity of the RSOA chip reaches -48.2 dBm at the level of bit error rate = 10^-3 for back-to-back, and the penalty for 50 km transmission is less than 1 dB when using polarization diversity.

关键词： OnU RSOA Coherent OnU based on 850 m-long cavity-RSOA for next-generation ultra-dense access network

Glial cells in the center of future ischemic stroke treatments

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neural Regeneration Research 2022年第12期17卷 2659-2660页

作者： ivóH.Hernández Maria JoséPérez-Álvarez Genomic Instability Group Spanish National Cancer Research Centre(CNIO)MadridSpain Departamento de Biología(Fisiología Animal)Facultad de Ciencias Universidad Autónoma de Madridand Instituto de Biología Molecular-CBMSOUAM/CSICMadridSpain

In the last century,increasing knowledge about glial cells has revealed their importance in brain physiology and disease and an exciting potential target for new therapeutic interventions(Hernández et al.,2021).Ischemic stroke is the most common of all types of *** the second leading cause of disability and mortality,ischemic stroke is a serious socio-economic burden *** it has been strongly associated with aging,during 2020 COVID-19 emerged as a new risk factor for ischemic stroke in younger patients(Cagnazzo et al.,2021).The only therapy or intervention currently available for humans is early reperfusion after the onset of the first ***,due to the high risk of brain hemorrhage,these treatments are suitable for only a small percentage of ***,reperfusion does not prevent post-injury neurodegeneration,hence the importance of finding new therapeutic alternatives to ameliorate ischemic damage and improve post-stroke quality of life.

关键词： mortality treatment younger

High-Temperature Thermodynamic Investigation of nano-Dispersed nitrides Obtained in Thermal Plasma

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Plasma Science and Technology 2007年第2期9卷 174-176页

作者： M. GEORGIEVA G. VISSOKOV iv. GRAnCHAROV L. BRAKALOV Department of Technology of Inorganic Substances University of Chemical Technology andMetal|urgy 8 K. Okhridski Blvd. 1756 Sofia Bulgaria

The nitrides of transient metals have a high hardness, thermal stability, remarkable wear resistance in aggressive chemical mediums, melted metals and alloys, high corrosion resistance, and low coefficient of electric resistance. Under the conditions of low-temperature argon plasma （LTP）, thermodynamic investigations were conducted in the process of obtaining of A1n, Tin and Si3n4 in a temperature range of 1000 K to 6000 K. To investigate the thermodynamic possibility of obtaining nitrides, a computer model was used which provided the equilibrium composition of gaseous and solid phases at different temperatures. The conditions for chemical equilibrium of the system were based on the minimization of Gibbs＇ energy.

关键词： plasma-chemical treatment nitrides thermodynamic analysis

Risk of cancer,with special reference to extra-intestinal malignancies,in patients with inflammatory bowel disease

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World Journal of Gastroenterology 2013年第48期19卷 9359-9365页

作者： Alicia Algaba iv.n Guerra ngel Castao Gema de la Poza Víctor M Castellano Montserrat López Fernando Bermejo Department of Gastroenterology Hospital Universitario de Fuenlabrada 28942 Madrid Spain Department of Pathology Hospital Universitario de Fuenlabrada28942 Madrid Spain

AIM:To determine the incidence and characteristics of intestinal and extra-intestinal cancers among patients with inflammatory bowel disease in a Spanish hospital and to compare them with those of the local ***:This was a prospective,observational,7-year follow-up,cohort *** incidence,incidence rates based on person-years of follow-up and relative risk were calculated for patients with inflammatory bowel disease and compared with the background *** incidence of cancer was determined using a hospital-based data registry from Hospital Universitario de *** data and details about time from diagnosis of inflammatory bowel disease to occurrence of cancer,disease extent,inflammatory bowel disease treatment,cancer therapy and cancer evolution were also collected in the inflammatory bowel disease ***:Eighteen of 590 patients with inflammatory bowel disease developed cancer[cumulative incidence=3%(95%CI:1.58-4.52)vs 2%(95%CI:1.99-2.11)in the background population;RR=1.5;95%CI:0.97-2.29].The cancer incidence among inflammatory bowel disease patients was 0.53%(95%CI:0.32-0.84)per patient-year of *** with inflammatory bowel disease had a significantly increased relative risk of urothelial carcinoma(RR=5.23,95%CI:1.95-13.87),appendiceal mucinous cystadenoma(RR=36.6,95%CI:7.92-138.4),neuroendocrine carcinoma(RR=13.1,95%CI:1.82-29.7)and rectal carcinoid(RR=8.94,95%CI:1.18-59.7).Colorectal cancer cases were not ***:The overall risk of cancer did not significantly increase in our inflammatory bowel disease ***,there was an increased risk of urinary bladder cancer and,with less statistical power,an increased risk of appendiceal mucinous cystadenoma and of neuroendocrine *** cancer risk was low in our series.

关键词： Extra-intestinal cancer Inflammatory bowel disease Cancer risk Background population Urothelial carcinoma Appendiceal mucinous cystadenoma neuroendocrine carcinoma Rectal carcinoid

Practical update on imaging and transcatheter aortic valve implantation

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World Journal of Cardiology 2015年第4期7卷 178-186页

作者： Gisela Feltes iv.n J nú ez-Gil Cardiovascular Unit Centro Médico Paris Interventional Cardiology Hospital Clínico San Carlos

After very rapid advances in the development of the technique and devices,transcatheter aortic valve implantation(named TAVI or TAVR),is today a reality that is here to *** has become the minimallyinvasive treatment option for high-risk and non-surgical patients with severe symptomatic aortic *** the participation of a multidisciplinary team for its implementation,cardiac imaging plays an important *** pre-assessment to determine the suitability of the patient,the access site,the type of device,to the guidance during the procedure,and ultimately the long term monitoring of the *** selection of the patient and device,correct placement of the stent-valve and early detection of complications are of paramount importance for procedural success and for patient *** technique has advantages and disadvantages,being the cardiologist who will determine the best approach according to the type of patient and the expertise of the center in each one of *** article summarizes the last contributions of the most common used imaging techniques,in each step of the procedure.

关键词： TAVI TAVR Echocardiography Multislice tomography Cardiac magnetic resonance Aortic stenosis

Enhanced optical absorption in semiconductor nano- particles enabled by nearfield dielectric scattering

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nano Research 2017年第4期10卷 1292-1301页

作者： Kowsalya D. Rasamani Jonathan J. Foley iv Brittney Beidelman Yugang Sun Department of Chemistry Temple University 1901 North 13th Street Philadelphia Pennsylvania 19122 USA Department of Chemistry William Paterson University 300 Pompton Road Wayne New Jersey 07470 USA Department of Physics Bryn Mawr College 101 North Merion Avenue Bryn Mawr Pennsylvania 19010 USA

The optical absorption of semiconducting AgBr nanocubes is significantly increased by up to 5 times in the measured spectral range when they are bonded to the surface of dielectric SiO2 nanospheres through electrostatic interaction. The absorption enhancement factor depends on the wavelength and the size of the SiO2 nanoparticles （nPs）. Finite-difference time-domain calculations provide the nearfield intensity mapping of a heterostructure that is composed of a AgBr nanocube in close contact with a SiO2 nanosphere. The electric-field distributions indicate the field enhancement near the SiO2/AgBr interface due to light scattering and absorption enhancement in the AgBr nanocube, implying that the enhanced scattering nearfield increases the absorption cross section of the AgBr nanocube. The absorption cross-section spectra calculated using Mie theory agree with the experimental observations. This discovery sheds light on the utilization of dielectric spherical particles to increase the absorption in semiconductor nPs, thus improving the light-harvesting efficiency for solar-energy conversion.

关键词： enhanced scattering nearfield dielectric scattering absorption enhancement Mie theory

Development of a Low Cost Pulsed Laser Deposition System for Thin Films Growth

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Modern Instrumentation 2012年第4期1卷 41-48页

作者： Marcos iv.n Oliva Carlos iv.n Zandalazini Juan Carlos Ferrero Hector Raúl Bertorello Centro Láser de Ciencias Moleculare Departamento de Fisicoquímica Facultad de Ciencias Químicas Universidad Nacional de Córdoba Ciudad Universitaria Córdoba Argentina Grupo de Ciencia de Materiales Facultad de Matemática Astronomía y Física Universidad Nacional de Córdoba Ciudad Universitaria Córdoba Argentina Instituto de Física Enrique Gaviola Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Córdoba Argentina

.Pulsed Laser Deposition (PLD) is a powerful technique to grow thin films. Oxides, Magnetics and superconducting materials have been obtained by PLD and theirs properties are strongly dependent of deposition parameters. The construction of a simple and cheap PLD system that is suitable for growing various thin films, including magnetic materials, controlling some deposition parameters is presented. The design characteristics and construction are presented for each one of the devices that compose this PLD system. The equipment has the possibility of carrying out films deposition using up to five targets under controlled atmosphere and substrate temperature. The system also allows controlling the cool off sample time after growing up films at high temperatures. A wide range of relative speeds between target and substrate axial rotation can be externally controlled. With the configuration and the dimensions adopted in their construction, a PLD system of great experimental flexibility is achieved, at a very low cost regarding the commercial systems. To evaluate their performance and effectiv.ness, the deposition characteristics of a BaFe12O19 film on (0001) sapphire substrate is presented.

关键词： Pulsed Laser Deposition Thin Film Multilayer

Dipolar spin relaxation of divacancy qubits in silicon carbide

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npj Computational Materials 2021年第1期7卷 1974-1984页

作者： Oscar Bulancea-Lindvall nguyen T.Son Igor A.Abrikosov Viktor ivády Department of Physics Chemistry and BiologyLinköping UniversitySE-58183 LinköpingSweden Wigner Research Centre for Physics Hungarian Academy of SciencesPO Box 49H-1525 BudapestHungary Max-Planck-Institut für Physik komplexer Systeme Nöthnitzer Straße 38D-01187 DresdenGermany

Divacancy spins implement qubits with outstanding characteristics and capabilities in an industrial semiconductor host On the other hand,there are still numerous open questions about the physics of these important defects,for instance,spin relaxation has not been thoroughly studied ***,we carry out a theoretical study on environmental spin-induced spin relaxation processes of divacancy qubits in the 4H polytype of silicon carbide(4H-SiC).We reveal all the relevant magnetic field values where the longitudinal spin relaxation time T,drops resonantly due to the coupling to either nuclear spins or electron *** quantitatively analyze the dependence of the T,time on the concentration of point defect spins and the applied magnetic field and provide ananalytical *** demonstrate that dipolar spin relaxation plays a significant role both in as-grown and ion-implanted samples and it often limits the coherence time of divacancy qubits in 4H-SiC.

关键词： relaxation vacancy resonant

Bilinear Model Proposal for Seismic Analysis Using Triple Friction Pendulum (TFP) Bearings

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Open Journal of Civil Engineering 2017年第1期7卷 14-31页

作者： iv.n Delgado Roberto Aguiar Pablo Caiza Departamento de Ciencias de la Tierra y la Construcción Universidad de Fuerzas Amadas ESPE Av. Gral. Rumiñ ahui s/n Quito Ecuador

An analytical model is presented for seismic analysis of triple friction pendulum bearings and validated using 81 bearing tests, each subjected to three cycles, with a duration of 12 seconds and using 250, 200 and 100 tons vertical loads. The main objective is to develop formulas for bilinear behavior using maximum, average and minimum friction coefficients to check which is the closest to the real behavior in the laboratory tests and comparatives curves plotting to observe the standard derivation. Parameters such as friction coefficients, effective stiffness, damping factor and vibration periods are analyzed to understand the structural behavior of the TPF bearings.

关键词： Triple Friction Pendulum Bearings