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Virtual Conductance Based Cascade Voltage Controller for VsCs in Islanded Operation Mode

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Journal of Modern Power systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： francisco jesús Matas-Díaz Manuel Barragán-Villarejo Juan Carlos Olives-Camps Juan Manuel Mauricio JoséMaría Maza-Ortega department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the lC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the lC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

Intravitreal dexamethasone implant in naive and previously treated patients with diabetic macular edema:a retrospective study

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International Journal of Ophthalmology(English edition) 2020年第10期13卷 1597-1605页

作者： Marta Medina-Baena Olga Cejudo-Corbalán Juan Ignacio García-Pulido María jesús Huertos-Carrillo Eloy Girela-lópez Hospital Universitario Puerto Real Puerto Real 11510CadizSpain University of Cordoba Cordoba 14004Spain

AIM:To assess the effect of the intravitreal dexamethasone implant(deX)Ozurdex on the best corrected visual acuity(BCVA)and central retinal thickness(CRT)in patients with diabetic macular edema(DME).METHODs:Totally 43 eyes(24 naive and 19 previously treated)were included in the *** and single-center study involved patients with a clinical diagnosed of DME,who received treatment with deX implant and had a follow-up of at least 12 *** endpoints included changes in BCVA and ***:At month 12,mean improvement in BCVA from baseline was 20.4±20.8 letters and 6.8±6.9 letters in naive and previously treated patients,respectively(P=0.0132).The naive patients achieved the BCVA improvement significantly faster(2.4±1.5 mo)than the previously treated ones(3.5±2.4 mo,P=0.0298;MannWhitney test).The proportion of eyes gaining≥15 letters was 54.2%and 21.1%in the non-previously treated and previously treated groups,respectively(P=0.0293).CRT was significantly reduced from 484.0±119.8 and 487.5±159.9μm to 272.0±39.2 and 233.5±65.7μm in the naive and previously treated patients,respectively;Psence of subretinal fluid was significantly associated with the proportion of patients achieving a BCVA improvement≥5 letters[HR(95%CI),1.23(1.04 to 1.45),P=0.0145];≥10 letters[HR(95%CI),1.75(1.10 to 2.77),P=0.0182];and≥15 letters[HR(95%CI),2.04(1.03 to 4.02),P=0.0407].naive patients received less deX implants throughout the study than the previously treated ones(1.8±0.6 vs 2.3±0.6,P=0.0172,respectively).Totally 9 patients(20.9%)have developed ocular hypertension,which was successfully controlled with topical hypotensive *** the 23 phakic eyes at baseline,5 eyes(21.7%)either had new onset lens opacity or progression of an existing opacity during the study *** of them(2 in the naive group and 2 in the previously treated one)required cataract surgery at months 4,6,6,and 6,***:The results obtained in this

关键词： diabetic macular edema dexamethasone implant Ozurdex visual acuity central retinal thickness naive patients

Effect of dietary near ideal amino acid profile on heat production of lactating sows exposed to thermal neutral and heat stress conditions

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Journal of Animal science and Biotechnology 2021年第2期12卷 739-754页

作者： s.Zhang J.s.Johnson n.l.Trottier department of Animal science Michigan State UniversityEast Lansing 48824USA UsDA-ARs livestock Behavior Research Unit West Lafayette 47907USA

Background:Reduced protein diet manifested potential to mitigate heat production based on the concept of ideal amino acid *** hypothesis of this study was that lactating sows fed a low crude protein(lCP)diet with supplemental amino acid produce less heat compared to those fed a high crude protein(HCP)diet under both thermal neutral(Tn)and heat stress(Hs)***:Thirty-two lactating sows were allotted to HCP(193 g CP/kg)and lCP(140 g CP/kg)diets under thermal neutral(Tn,21±1.5°C)or cycling heat stress(Hs,32±1.5°C daytime and 24±1.5°C nighttime)*** contained 0.90%sID lysine and 10.8 MJ/kg net *** pressure indirect calorimeters were used to measure gas exchange in individual sows with litters,and individual piglets on days 4,8,14 and *** and litter weights were recorded on days 1,10 and ***:sow total heat production(THP)was calculated by subtracting litter THP from sow+litter THP based on *** BW and body protein(BP)loss was greater for lCP diet compared to HCP diet in peak lactation(Pnd Pspectively)and throughout the entire lactation period(Pnd P=0.056,respectively)under Hs ***-stressed sows fed HCP diet had higher(Pl temperature at 13:00(Pnd 19:00(Pnd higher respiration rate at 07:00(Pnd 19:00(Pn sows fed HCP *** sows fed lCP diet,those under Hs tended to have higher(P=0.098)rectal temperature at 13:00 and had higher(Pspiration rate at 07:00,13:00 and 19:00 compared to Tn *** relationship between daily THP and days in lactation of sows fed lCP diet was quadratic(Pn ascending trend until day 14 and a descending trend from days 14 to *** fed lCP diet had lower daily THP at day 18(Pse fed the HCP diet under Hs ***:Reduction in THP in sows fed lCP diet was largely associated with THP on day 18 of lactation under Hs *** lCP die

关键词： Amino acid Heat stress lactating sows low protein diet Total heat production

Prolonged cholestasis after raloxifene and fenofibrate interaction: A case report

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World Journal of Gastroenterology 2006年第32期12卷 5244-5246页

作者： M Isabel lucena raúl J Andrade luis Vicioso f jesús González Ketevan Pachkoria Beatriz García-Mu(n|~)oz Clinical Pharmacology service Virgen de la Victoria University Hospital School of MedicineMalagaSpain liver Unit Gastroenterology service Virgen de la Victoria University HospitalSchool of MedicineMálagaSpain department of Pathology Virgen de la Victoria University Hospital School of MedicineMálagaSpain Institute of Biopathology and Regenerative Medicine University of Granada Spain Clinical Pharmacology service Virgen de la Victoria University Hospital School of MedicineMálagaSpain

Assigning causality in drug-induced liver injury is challenging particularly when more than one drug could be responsible. We report a woman on long-term therapy with raloxifen who developed acute cholestasis shortly after starting fenofibrate. The picture evolved into chronic cholestasis. We hypothesized that an interaction at the metabolic level could have triggered the presentation of hepatotoxicity after a very short time of exposure to fenofibrate in this patient. The findings of an overexpression of vascular endothelial growth factor in the liver biopsy suggest that angiogenesis might play a role in the persistance of toxic cholestasis.

关键词： raloxifene fenofibrate Drug-drug interactions Hepatotoxicity Causality assessment

Y^(3+) substituting-adjusted mechanical,dielectric,and impedance properties of cobalt copper zinc nanoferrites for high frequency applications

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Journal of rare Earths 2023年第10期41卷 1597-1605,I0005页

作者： s.f.Mansour n.s.Al-Bassami M.Afifi M.A.Abdo Physics department Faculty of ScienceZagazig UniversityZagazigEgypt General studies department Jubail Industrial CollegeJubail Industrial CitySaudi Arabia faculty of nanotechnology for Postgraduate studies Cairo UniversityEl-Sheikh Zayed12588Egypt

Upgrading mechanical-dielectric features of ferrites through rare-earth yttrium(Y^(3+))doping provides feasibility to evolving high-frequency electronic *** paper reports the mechanical and dielectric properties of Co_(0.5)Cu_(0.25)Zn_(0.25)Y_(x)fe_(2-x)O_(4)ferrite nanoparticles labeled as CCZYf#0,CCZYf#1,CCZYf#2,CCZYf#3,CCZYf#4 and CCZYf#5 for x=0.***.0.02,0.04,0.06,0.08,and 0.1,*** frequency and temperature dependence of dielectric parameters and co nductivity of all CCZYf nanoferrites are well *** nanoferrite CCZYf#5 has the highest dielectric constant(enhancing ratio 170%)and the highest conductivity(enhancing ratio 7125.81%)compared with the undoped *** plots of all CCZYf nano ferrites manifest two arcs;the main reasons for the dielectric process are the grain boundaries and bulk *** impedance parameters were determined,which showed the effective role of Y^(3+)ions on their *** nanoferrite CCZYf#5 has the highest grain boundaries capacitance(with enhancing ratio of 59.40%)and the highest grains capacitance(with enhancing ratio of 22.53%)with a relaxation time decrement efficiency of 62.51%.An ultrasonic flaw detector was utilized to determine the elastic moduli of all CCZYf *** nanoferrite CCZYf#5 has the highest longitudinal modulus(with enhancing ratio of 20.95%),the highest shear modulus(with enhancing ratio of48.72%),highest Young's modulus(with enhancing ratio of 88.47%),the highest bulk modulus(with enhancing ratio 13.27%)and the highest micro hardness(with enhancing ratio 77.77%).Hence,Y3+tuned Co-Cu-Zn nanoferrites possess new opportunities for high-frequency and storage applications.

关键词： nanoferrites rare arth ions Mechanical properties Dielectric parameters Impedance spectroscopy

site Characterization Index for Continuous Power Quality Monitoring Based on Higher-order statistics

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Journal of Modern Power systems and Clean Energy 2022年第1期10卷 222-231页

作者： Olivia florencias-Oliveros Juan-José González-de-la-Rosa Jose-María sierra-fernández Agustín Agüera-Pérez Manuel-jesús Espinosa-Gavira José-Carlos Palomares-salas department of Automation Engineering ElectronicsArchitecture and Computers NetworksResearch Group TIC168Higher Polytechnic SchoolUniversity of CádizAlgeciras 11202Spain

The high penetration of distributed generation(DG)has set up a challenge for energy management and consequently for the monitoring and assessment of power quality(PQ).Besides,there are new types of disturbances owing to the uncontrolled connections of non-linear *** stochastic behaviour triggers the need for new holistic indicators which also deal with big data of PQ in terms of compression and scalability so as to extract the useful information regarding different network states and the prevailing PQ disturbances for future risk assessment and energy management *** and continuous monitoring would guarantee the report to claim for damages and to assess the risk of PQ *** this context,we propose a measurement method that postulates the use of two-dimensional(2D)diagrams based on higher-order statistics(HOss)and a previous voltage quality index that assesses the voltage supply waveform in a continous monitoring *** suitable for both PQ and reliability applications,the results conclude that the inclusion of HOs measurements in the industrial metrological reports helps characterize the deviations of the voltage supply waveform,extracting the individual customers’pattern fingerprint,and compressing the data from both time and spatial *** method allows a continuous and robust performance needed in the sG ***,the method can be used by an average consumer as a probabilistic method to assess the risk of PQ deviations in site characterization.

关键词： Continuous statistical monitoring big data data compression higher-order statistics(HOss) power quality(PQ)

structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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Journal of rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A García-Murillo A Carrillo-Romo f de J Cruz-santiago l A Chadeyron G Morales-ramírez A de J Velumani s T.A. Post-graduate student. Instituto Politécnico nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de Chimie de Clermont-ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France department of Electrical Engineering (sEEs) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, lCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with fT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-raman analyses. The particle size（～30 nm） was estimated using the scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

Estimation of the carbon pool in soil and above-ground biomass within mangrove forests in southeast Mexico using allometric equations

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Journal of forestry Research 2014年第1期25卷 129-134页

作者： jesús Jaime Guerra-santos Rosa María Cerón-Bretón Julia Griselda Cerón-Bretón Diana lizett Damián-Hernández Reyna Cristina s.n.hez-Junco Emma del Carmen Guevara Carrió Centro de Investigación de Ciencias Ambientales-Universidad Autónoma del Carmen Av.Abasolo s/n.Col.Renovación 2da.Sección C.P.24180.Cd.del CarmenCampecheMéxico

We report the results of carbon stored in soil and aboveground biomass from the most important area of mangroves in Mexico, with dominant vegetation of Red mangrove （Rhizophora mangle l.）, Black mangrove （Avicennia germinans l.）, white mangrove （laguncularia racemosa Gaertn.） and button mangrove （Conocarpus erectus l.）. We sampled soils with high fertility during the dry season in 2009 and 2010 at three sites on Atasta Peninsula, Campeche. We used allometric equations to estimate above ground biomass （AGB） of trees. AGB was higher in C. erectus （253.18±32.17 t？ha-1）, lower in A. germinans （161.93±12.63 t？ha-1）, and intermediate in R. mangle （181.70±16.58 t？ha-1） and l. racemosa （206.07±19.12 t？ha-1）. Of the three studied sites, the highest absolute value for AGB was 279.72 t？ha-1 in button mangrove forest at any single site. Carbon stored in soil at the three sites ranged from 36.80±10.27 to 235.77±66.11 t？ha-1. The Tukey test （p 〈0.05） made for AGB was higher for black mangrove showed significant differences in soil carbon content between black mangrove and button mangrove. C. erectus had higher AGB compared with the other species. A. germinans trees had lower AGB because they grew in hypersaline environments, which reduced their development. C. erectus grew on higher ground where soils were richer in nutrients. AGB tended to be low in areas near the sea and increased with distance from the coast. A. germinans usually grew on recently deposited sediments. We assumed that all sites have the same potential to store carbon in soil, and then we found that there were no significant differences in carbon content between the three samples sites： all sites had potential to store carbon for long periods. Carbon storage at the three sampling sites in the state of Campeche, Mexico, was higher than that reported for other locations.

关键词： carbon storage Rhizophora mangle laguncularia racemosa,Avicennia germinans tree biomass

Recent surface marine sediments of Cocos Island in Costa Rica

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International Journal of sediment Research 2014年第1期29卷 59-72页

作者： Jeffrey A.sIBAJA-CORdeRO jesús s.TROnCOsO Eddy GóMEZ-raMíREZ Escuela de Biología&Centro de Investigación en Ciencias del Mary limnología (CIMAR) Universidad de Costa Rica Dr.grad.by departamento de Ecología y Biología Animal Facultad de Ciencias del MarUniversidad de Vigo departamento de Ecología y Biología Animal Facultad de Ciencias del MarUniversidad de VigoCampus Lagoas Marcosende Centro de Investigación en Ciencias del Mary limnología(CIMAR) Universidad de Costa RicaSan Pedro 115012 060 San JoséCosta Rica Dr.(Cand).departamento de Biología Facultad de Ciencias del Mary AmbientalesUniversidad de Cádiz

subtidal sediments of Isla del Coco(Cocos Island),Costa Rica were described in their grain size,sorting,organic matter,and carbonates from 27 dredge samples(3-75 m),collected in April *** organic matter range between 1.37-3.31%and carbonates presented a mean of 74±17%.The sorting was moderately or *** grain size ranged between *** pattern is that sediment change from inner to mouth of *** and gravel fractions increased offshore and organic matter have high values inner the *** of vegetal debris and mud was from the rivers of this island covered with rain and cloud forest.

关键词： sand bottom sorting Organic matter Carbonates Isla del Coco