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Seasonal Variability in the Distribution of Phytoplankton in Paracas Bay/Peru, as a Response to Environmental Conditions

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Journal of Environmental Science and Engineering(B) 2019年第1期8卷 7-16页

作者： Sonia Sánchez Nelly Jacobo Avy Bernales Augusto Franco jorge quispe Georgina Flores Laboratory of Phytoplankton and Primary Production Instituto del Mar del Peru Chucuito Callao 07001 Peru Functional Area of Research in Physical Oceanography Instituto del Mar del Peru Chucuito Callao 07001 Peru Functional Area of Research in Chemical Oceanography Instituto del Mar del Peru Chucuito Callao 07001 Peru

During 2013-2015, a series of bio-oceanographic surveys was carried out in Paracas bay (13°50′ S). This coastal habitat represents a transition between open ocean and continent. Changes in distribution and structure of phytoplankton community and presence of noxious algal blooms were evaluated. The vertical stability of water column was analyzed on transects of temperature, salinity and potential density. Stratification of the water column as well as other variables presented a seasonal behavior. The maximum values were recorded in summer and were directly related to the seasonal heat flux in surface layers of the bay, while in winter this stratification index was minimum. N/P ratios showed a seasonal variation with highest values in winter and lowest ones in summer. Silicate concentrations were minimum mainly during in spring due to high biological fixation. The dominance of diatoms was evident in winter and spring, with maximum abundances of r strategists. The diversity and equitability indexes were low (< 3 bits?cel^-1 and 0.31, respectively). During summer, there was a greater contribution of oceanic species, with high concentrations of the dinoflagellate Prorocentrum cordatum;and a higher frequency of algal blooms (Akashiwo sanguinea, Heterosigma akashiwo, Eutreptiella gymnastica and Gonyaulax polygramma) in the coastal zone. Silicates and pH presented a significant correlation with diatom abundances in spring, whilst dinoflagellates were associated to warm and salinity conditions in summer. Weak correlations were found for potentially toxic dinoflagellates with temperature and for Pseudo-nitzschia group with silicates and phosphates.

关键词： HAB transition zones inshore ecosystem Paracas bay-Peru phytoplankton

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Transmission line protection challenges influenced by inverter-based resources:a review

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Protection and Control of Modern Power Systems 2022年第1期7卷 406-422页

作者： Juan Carlos quispe Eduardo Orduña Institute of Electrical and Energy-CONICET Universidad Nacional de San JuanSan JuanArgentina Universidad Tecnológica del Perú LimaPeru

High penetration of renewable energy sources(RES)leads to new challenges for protection *** schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,while the RES dynamic response,mainly governed by inverters,is not ***,some relevant algorithms of transmission line protection are experiencing challenges because of the fact that magnitude and phase angle com-parison,amount of negative-sequence,and short-circuit current level are affected by the ***,an in-depth study of this issue is necessary,one which considers the main causes and new methodological criteria *** work presents an extensive literature review of the evaluation of electrical protection performance and the effects of RES connected to a power grid through *** data on many representative publications related to this topic are obtained to show the current research lines and their proposed *** addition,this work identi-fies the main protection functions affected and describes the new protection schemes that consider ***,an analysis and discussion of the selected bibliography are presented.

关键词： Inverter-based resources Inverter control system Photovoltaic plant Transmission line protection Wind farm

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Setting large-and medium-sized mammal restoration goals in a last mountain Chaco remnant from central Argentina

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Ecological Processes 2023年第1期12卷 301-312页

作者： Daniel Renison Harold Rusbelth quispe-Melgar GAErica Cuyckens Ana MCingolani Centro de Ecología y Recursos Naturales Renovables Dr.Ricardo LutiInstituto de Investigaciones Biológicas y TecnológicasUniversidad Nacional de Córdoba-CONICETAv.Vélez Sarsfield 1611X5016GCA CórdobaArgentina Ecosistemas argentinos 27 de abril 2050CórdobaCórdobaArgentina Facultad de Ciencias de la Salud Universidad ContinentalHuancayoPeru Centro de Estudios Territoriales Ambientales y Sociales(CETAS UNJu)Instituto de Ecorregiones Andinas(INECOAUNJu-CONICET)Alberdi 474600San Salvador de JujuyJujuyArgentina Instituto Multidisciplinario de Biología Vegetal CONICET-Universidad Nacional de CórdobaAv.Vélez Sarsfield 1611X5016GCA CórdobaArgentina.

Background Setting large-and medium-sized wild mammal(≥2 kg)restoration goals is important due to their role as ecosystem engineers and generalized numeric ***,determining wild mammal restoration goals is very challenging due to difficulties in obtaining data on current mammal density and due to unclear information on what mammal density values should be used as a *** we chose a 154 ha conservation area within one of the last remnants of the mountainous Chaco from central *** suspected that extensive and unreported defaunation had occurred due to past human pressure and the introduction of non-native *** conduct the analyses,we used a simplified technique that integrates methods used in rangeland and ecological *** Eight native mammal species including only one herbivore species,and four non-native mammal species including three herbivore species were detected during 6113 camera trap *** used known cattle densities as estimated by droppings and direct counts,together with the relative abundance indexes obtained from camera trap photos to calculate the densities of the other species,correcting for mammal *** for the least and most abundant native species were 0.2 and 1.33 individuals km^(-2),respectively;and for non-native species,0.03 and 5.00 individuals km^(-2),*** and non-native species represented 0.8%and 99.2%,respectively,of the bio-mass *** values for native herbivore biomass,as estimated from net primary productivity,were 68 times higher than values estimated for the study area(3179 vs.46.5 kg km^(-2)).Conclusions There is an urgent need to increase native mammals,with special emphasis on herbivore biomass and richness,while non-native mammal numbers must be *** cattle are widespread in large portions of the globe and there is a lot of experience estimating their abundances,the ratio method we used extrapolating from cattle to other large-and medium-s

关键词： Camera trap Mammal survey Reference biomass Exotic mammal

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Oxidative Degradation of Thermoplastic Starch Induced by UV Radiation

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Journal of Renewable Materials 2019年第4期7卷 383-391页

作者： Mayte M.quispe Olivia V.López Marcelo A.Villar Planta Piloto de Ingeniería Química PLAPIQUI(UNS CONICET)Bahía Blanca(8000)Argentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca(8000)Argentina

Among biopolymers,thermoplastic starch(TPS)is a good candidate to obtain biomaterials because of its natural origin,biodegradable character,and *** to ultraviolet(UV)radiation causes significant degradation of starch-based materials,inducing photooxidative reactions which result in breaking of polymer chains,production of free radical,and reduction of molar *** changes produce a deterioration of TPS mechanical properties,leading to useless materials after an unpredictable *** this work,changes induced on TPS by UV radiation,analyzing structural properties and mechanical behavior,are *** was obtained through thermo-mechanical processing of native corn starch in the presence of water(45%w/w)and glycerol(30%w/w)as *** were obtained by thermocompression and,before testing,specimens were conditioned to reduce material *** process was performed by exposing TPS to 264 h UV radiation in a weathering test ***’s weight loss was determined *** changes were studied by Fourier Transform Infrared Spectroscopy(FTIR)and morphological modifications were analyzed by Scanning Electron Microscopy(SEM).Reduction of weight average molar mass was measured by Static Light Scattering(SLS).Changes in mechanical properties were studied from tensile *** 96 h exposure,TPS specimens presented a weight reduction of 4-6%,mainly attributed to plasticizers lost by *** observations showed that UV radiation induced morphological changes on TPS,evidenced by an increment of specimens *** FTIR,it was detected the presence of an additional band located at 1726 cm-1 in samples submitted to UV radiation,attributed to the formation of-C=O *** average molar mass of native starch was in the order of 107 g *** exposure to UV radiation decreased significantly its molar mass,confirming molecular degradation of the *** TPS was exposed during 48 h,it

关键词： Thermoplastic starch UV radiation structural properties mechanical behavior

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Time-frequency multiresolution of fault-generated transient signals in transmission lines using a morphological filter

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Protection and Control of Modern Power Systems 2023年第2期8卷 85-98页

作者： Juan Carlos quispe John Morales Eduardo Orduna Carlo Liebermann Michael Bruhns Peter Schegner Universidad Nacional de San Juan-CONICET San JuanArgentina Universidad Tecnológica del Perú LimaPerú Technical University of Dresden DresdenGermany

The ongoing transformation of electrical power systems highlights the weaknesses of the protection schemes of traditional devices because they are designed and configured according to traditional characteristics of the ***,this work proposes a new methodology to study the fault-generated high frequency transient signals in transmission lines through multiresolution *** high frequency components are determined by a new digital filtering technique based on mathematical morphology theory and a spectral energy ***,wide spectra of signals in the time–frequency domain are *** performance of this method is verified on an electrical power system modeled in ATP-Draw,where simulation and test signals are developed for different locations,fault resistances,inception angles,high frequency noises,sampling frequencies,types of faults,and shapes of the structuring *** results show the characteristics of the fault such as the traveling wave frequency,location,and starting time.

关键词： Digital filter High frequency Mathematical morphology Time–frequency Traveling waves

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Enhanced desulfurization performance of hybrid membranes using embedded hierarchical porous SBA-15

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 661-672页

作者： Ye Zhang Jian Song Josue quispe Mayta Fusheng Pan Xue Ga Mei Li Yimeng Song Meidi Wang Xingzhong Cao Zhongyi Jiang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Multi-discipline Research Division Institute of High Energy PhysicsChinese Academy of SciencesBejing 100049China

The utilization of materials with a hierarchical porous structure as multi-functional additives is highly attractive in the preparation of hybrid *** this study,novel hybrid membranes are designed by embed-ding hierarchical porous Santa Barbara Amorphous 15(SBA-15)with a dual-pore architecture(micropores and mesopores)for pervaporation *** SBA-15 with cylindrical mesopores provides molecular transport expressways to ensure improved permeability,while micropores on the wall have molecular sieving effects that are essential for the enhancement of permselectivity of thiophene *** thiophene/n-octane mixture as a model system,the hybrid membrane with embedded 6 wt-%SBA-15 exhibits optimal pervaporation desulfurization performance with a permeation flux of 22.07 kg·m^-2·h^-1 and an enrichment factor of ***,the detailed structure and properties of hybrid membranes are systematically *** study demonstrates the immense potential of hierarchical porous materials as additives in membranes to simultaneously increase permeability and permselectivity.

关键词： hybrid membranes hierarchical porous SBA-15 sieving effect pervaporation desulfurization

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多级结构分子筛杂化膜制备与渗透蒸发脱硫性能研究

多级结构分子筛杂化膜制备与渗透蒸发脱硫性能研究

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作者： quispe Mayta Josue 天津大学

学位级别：硕士

渗透蒸发是一种具有工业应用的膜分离技术并且受到广泛研究。它具有高效、低能耗、低污染的优点,具有广阔的应用前景。高性能膜材料是实现大规模工业应用和降低成本的关键。评价膜分离性能的两个主要因素是:选择性和渗透通量。膜中通道... 详细信息

渗透蒸发是一种具有工业应用的膜分离技术并且受到广泛研究。它具有高效、低能耗、低污染的优点,具有广阔的应用前景。高性能膜材料是实现大规模工业应用和降低成本的关键。评价膜分离性能的两个主要因素是:选择性和渗透通量。膜中通道的构建是提高传质性能,获得高性能膜的有效方法。本研究旨在构建促进膜的通道来提高对汽油的脱硫性能。主要成果如下:MCM-41与聚醚共聚酰胺(Pebax)基质共混制备杂化膜。由于MCM-41的微孔(1.5 nm)和介孔(3.5 nm)多级孔结构,构建了杂化膜的连续通道,有效地降低了扩散阻力,提高了渗透通量。与此同时,通过优化膜的结晶性能和自由体积特性,提高了杂化膜的分离性能。当MCM-41的填充量为4 wt%时,杂化膜的渗透通量为21.97 kg/(mh),富集因子为6.75。该膜具有良好的长期操作稳定性。SBA-15也有微孔(0.57-0.62 nm)和介孔(6-6.5 nm)多级孔结构。当SBA-15加入到Pebax基质中时,由于微孔尺寸介于噻吩和正辛烷之间可以确保选择性,而介孔作为连续的通道,使渗透分子在膜中快速传输。该杂化膜具有良好的热稳定性和抗溶胀性能,在高温下具有良好的分离性能。当SBA-15填充量为6wt%时,杂化膜的渗透通量为22.07 kg/(mh),富集因子为6.76。该膜同样具有良好的长期操作稳定性。

关键词：分子筛杂化膜多级孔渗透蒸发汽油脱硫

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Performance between the Hydraulic Gradient Method and the Perturbation Method for the Analysis of Water Supply Networks

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Journal of Environmental Science and Engineering(A) 2020年第6期9卷 217-226页

作者： Iván Ayala Bizarro Elviz quispe García Marco Lopez Barrantes Freddy Marrero Saucedo Omar CaballeroSanchez Hugo Lujan Jeri Carlos Gaspar Paco jorge Ortega Vargas Department of Civil Engineering National University of HuancavelicaHuancavelica 09001Peru

The HGM(Hydraulic Gradient Method),it is used in most of the current commercial software,such as EPANET,WaterCAD,MikeNet,among others,the same that corresponds to an iterative method that depends on initial estimated parameters and programming structures that ensure convergence to obtain results with the highest precision,in addition to this the method makes use of non-linear equation ***,the execution time for large extensions of water distribution networks is considerably *** the other hand,the PM(Perturbation Method),is a new direct solution method,which makes use of principles of quantum mechanics to transform nonlinear equations into simpler linear *** a simple and robust optimization method that only requires simple and direct mathematical *** the MathCad and Python programming languages as a verification tool,multiple tests were carried out,the results for the hydraulic parameters showing that the flow rates and pressures obtained by the HGM and the PM are extremely similar,in the same way the execution time(time run)have been 77.09%favorable to the *** other words,the PM presents efficiency to estimate the hydraulic characteristics such as the pressures at the nodes and the velocities in the pipes of the drinking water distribution networks.

关键词： Perturbation method quantum mechanics hydraulic gradient

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Brief potentially ictal rhythmic discharges on intraoperative electrocorticography predict a good outcome of focal cortical dysplasia after surgical resection: a case report

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Acta Epileptologica 2023年第3期6卷 163-167页

作者： Sofía S.Sánchez‑Boluarte Wilfor Aguirre‑quispe Manuel Herrera Aramburú William O.Tatum Walter De La Cruz Ramírez School of Medicine Cesar Vallejo UniversityAv.Victor LarcoTrujilloTrujillo 1770Peru Departamento de Epilepsia Instituto Nacional de Ciencias NeurológicasJr.Ancash 1271LimaLima 15001Peru Neurosciences Clinical Effectiveness and Public Health Research GroupUniversidad Científica del SurPanamericana Sur 19Villa EL SalvadorLimaLima 15067Peru Department of Neurology Mayo ClinicMangurian Bldg.Fourth Floor4500 San Pablo RoadFL 32224 JacksonvilleUSA

Background Focal cortical dysplasia(FCD)is a common cause of drug-resistant ***(EEG)biomarkers that predict good postoperative outcomes are essential for identifying patients with focal *** presentation We report the case of a 21-year-old female with seizure onset at the age of 9,characterized by left-hand dystonic posturing and impaired awareness,which evolved to bilateral tonic-clonic seizures,evaluated in a neurological referral center in Lima,*** 6-h video-EEG,interictal EEG revealing focal brief potentially ictal rhythmic discharges(BIRDs)over the right frontal central region,lasting less than 10 *** ictal features were characterized by low-voltage fast activity over the same *** magnetic resonance imaging(MRI)demonstrated a focal lesion of focal cortical dysplasia type II in the right frontal *** patient underwent a lesionectomy guided by electrocorticography,which showed continuous *** showing a brief burst of spikes lasting longer than 0.5 s,were also identified on intraoperative electrocorticography(ECoG)and helped define the extent of *** patient obtained an Engel Outcome Class IA at 6 years of *** The atypical BIRDs on ECoG can be used as a prognostic biomarker for prolonged seizure-freedom outcome in patients with *** reports are needed in developing countries with and without brain MRI lesions to advance outpatient presurgical evaluations despite limited resources.

关键词： Electrocorticography Cortical dysplasia-focal epilepsy syndrome Drug-resistant epilepsy Frontal lobe epilepsy

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Experimental model standardizing polyvinyl alcohol hydrogel to simulate endoscopic ultrasound and endoscopic ultrasoundelastography

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World Journal of Gastroenterology 2020年第34期26卷 5169-5180页

作者： Elymir S Galvis-García Sergio Sobrino-Cossío Arturo Reding-Bernal Yesica Contreras-Marín Karina Solórzano-Acevedo Patricia González-Zavala Rosa M quispe-Siccha Unidad de Endoscopía Gastrointestinal Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico Unidad de Endoscopia y Fisiología Digestiva HospitalÁngeles del PedregalMexico 10700Mexico Dirección de Investigación Hospital General de México“Dr.Eduardo Liceaga”Mexico 06720Mexico Unidad Profesional Interdisciplinaria de Biotecnología and Unidad de Investigación y Desarrollo Tecnológico Instituto Politécnico Nacional and Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico Instituto de Investigaciones en Materiales and Unidad de Investigación y Desarrollo Tecnológico Universidad Nacional Autónoma de México and Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico Unidad de Investigación y Desarrollo Tecnológico Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico

BACKGROUND Endoscopic ultrasound(EUS)and endoscopic ultrasound elastography(EUS-E)simulation lessens the learning curve;however,models lack realism,diminishing *** To standardize the mechanical properties of polyvinyl alcohol(PVA)hydrogel for simulating organs and digestive *** PVA hydrogel(Sigma Aldrich,degree of hydrolysis 99%)for simulating EUS/EUS-E lesions was investigated in Unidad de Investigación y Desarrollo Tecnológico at Hospital General de México“*** Liceaga”,Mexico *** evaluated physical,contrast,elasticity and deformation coefficient characteristics in lesions,applying Kappa’s concordance and satisfaction questionnaire(Likert 4-points).RESULTS PVA hydrogel showed stable mechanical *** depended on molecular weight(MW)and concentration(C).PVA bblocks with the greatest density showed lowest tensile strength(r=-0.8,P=0.01).Lesions were EUSgraphically *** and heterogeneous examples were created from PVA blocks or PVA phantoms,exceeding(MW2=146000-186000,C9=15%and C10=20%)with a density under(MW1=85000-124000,C1=7%and C2=9%).We calculated elasticity and deformation parameters of solid(blue)areas,contrasting with the norm(Kappa=0.8;high degree of satisfaction).CONCLUSION PVA hydrogels were appropriate for simulating organs and digestive lesions using EUS/EUS-E,facilitating practice and reducing *** amplified skills,while reducing the learning curve.

关键词： Endoscopic ultrasound simulators in endoscopy Polyvinyl alcohol Endoscopic ultrasound Endoscopic ultrasound elastography Strain Elasticity

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