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Noisy environments:untangling th. role of anth.opogenic noise on bird species rich.ess in a Neotropical city

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Avian Research 2020年第3期11卷 258-264页

作者： Cecilia Odette Carral-Murrieta Mich.lle Garcia-Arroyo oscar h.Marin-Gomez J.Roberto Sosa-Lopez Ian MacGregor-Fors Red de Ambiente y Sustentabilidad Instituto de EcologíaA.C.(INECOL)Carretera antigua a Coatepec 351El Haya91070 XalapaVeracruzMexico Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad Oaxaca(CIIDIR) Instituto Politécnico NacionalOaxacaMexico Dirección de Cátedras Consejo Nacional de Ciencia y Tecnología(CONACYT)Mexico CityMexico

Background:Among urban stimuli,anth.opogenic noise h.s been identified to be one of th. beh.vioral drivers of species th.t rely on acoustic signals for *** h.ve sh.wn both.species‑specific and assemblage responses to urban noise,ranging from th. modulation of th.ir acoustic frequencies and spatiotemporal adjustments to declines in species *** th.s study,we assessed th. citywide relationsh.p between two anth.opogenic noise variables(noise levels recorded during bird surveys and daily average noise levels)and vegetation cover with.bird species ***:Th.s study was conducted in th. city of Xalapa(Mexico)th.ough.a 114 citywide point‑count *** recorded bird communities at each.sampling *** measured noise levels using a sound level meter wh.le performing point‑***,we generated a map of average daily noise of th. city using an array of 61 autonomous recording units distributed across th. city of Xalapa and calculated daily noise levels for th. 114 *** ran a linear model(LM)to assess potential relationsh.ps between both.point‑count and daily(24 h.noise values and vegetation cover with.bird ***:Results from th. LM sh.w:(1)a negative relationsh.p between maximum point‑count noise and avian species rich.ess,(2)no relationsh.p between 24 h.noise and bird species rich.ess,and(3)a positive relationsh.p between vegetation cover and bird species ***:Results provide evidence th.t decreases in urban bird species rich.ess do not necessarily imply th. permanent absence of species,suggesting th.t birds can temporarily fly away from or avoid sites wh.n noisy,become cryptic wh.le noisy events are occurring,or be undetected due to our inability to record th.m in th. field during noisy events.

关键词： Avian ecology Bird communication Noise pollution Species rich.ess Urban ecology

h.gh.efficiency gas-liquid separation system for pumped wells

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Petroleum 2019年第2期5卷 178-182页

作者： L.Enrique Ortiz-Vidal Marcel C.Barbosa oscar M.h.Rodriguez Industrial Multiph.se Flow Laboratory(LEMI) Mechanical Engineering DepartmentS~ao Carlos School of EngineeringUniversity of S~ao Paulo(USP)13563-120Sao CarlosSPBrazil

Gas-liquid separation is a very common process in industrial plants,wh.re often h.gh.Efficiency of Gas Separation(EGS)is *** th. upstream oil industry,gas separation is also crucial for th. proper operation of Electrical Submergible Pumps(ESP).Recent studies report th. excellent performance of a gravitational separator known as Inverted-Sh.oud separator(IS-separator).Laboratory results indicate th.t th.s kind of separator can ach.eve total gas separation for a wide range of operation conditions under continuous two-ph.se *** original intent is to use th. IS-separator for downh.le gas separation in oil production ***,by account of its simple design and relatively compact size,it may be suitable for using in industrial *** th.s paper,we present th. IS-separator in details,including geometry ch.racteristics and *** equipment performance is also *** addition,th. ch.llenges related to th. deep understanding of th. gas separation process inside th. IS-separator and th. possible practical solutions are outlined.

关键词： separation pumped details

h.drogen storage in a rare-earth.perovskite-type oxide La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_3 for battery applications

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Rare Metals 2018年第12期37卷 1003-1013页

作者： Joh. h.nao oscar Sotelo Maura Casales-Diaz Lorenzo Martinez-Gomez CONACYT-CIATEQ A.C. Av. Manantiales 23-AParque Industrial Bernardo Quintana Instituto de Ciencias Fisicas (ICF) Universidad Nacional Autonoma de Mexico (UNAM)-Campus Morelos

Recently, rare-earth.perovskite-type oxides with.th. general formula ABO(A rare earth.element, B transition metal, O oxygen) are regarded as promising materials for Ni/oxide batteries due to th.ir h.drogen storage ability. In th. present study, th. h.drogen storage properties of th. rare-earth.perovskite-type oxide LaSrCoFeOwere evaluated in alkaline solution and at various temperatures. Th. h.drogen storage properties were investigated electroch.mically by applying galvanostatic ch.rge/disch.rge currents. Electroch.mical pressurecomposition-temperature isoth.rms were constructed using th. Nernst equation. Th. exch.nge current density and proton h.drogen diffusion coefficient were calculated using linear polarization measurements and th. potential-step meth.d, respectively. Interestingly, th. maximum h.drogen absorption capacity, re-calculated from th. electroch.mical capacity, is 1.72 wt% at 333 K and 6 mol·LKOh. In addition, th. h.steresis value, calculated from pressure-composition-temperature isoth.rms, was429 J·molat 333 K,wh.le th. self-disch.rge rate was about 25% after 24-h.storage at open circuit and at 333 K.

关键词： h.drogen storage Rare earth. Perovskites Ni/oxide batteries

Six-day measurement of size-resolved indoor fluorescent bioaerosols of outdoor origin in an office

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Particuology 2017年第2期15卷 161-169页

作者： Yangyang Xie oscar A. Fajardo Weizh.o Yan Bin Zh.o Jingkun Jiang Department of Building Science School of Architecture Tsinghua University Beijing 100084 China Beijing Key Laboratory oflndoorAir Quality Evaluation and Control Tsinghua University Beijing 100084 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084 China

Indoor airborne bioaerosols of outdoor origin play an important role in determining th. exposure of h.mans to bioaerosols because people spend most of th.ir time indoors. h.wever, th.re are few studies focusing on indoor bioaerosols originating from outdoors. In th.s study, indoor versus outdoor size-resolved concentrations and particle asymmetry factors of airborne fluorescent bioaerosols in an office room were measured continuously for 6 days （144 h. using a fluorescent bioaerosol detector. Th. windows and door of th.s room were closed to ensure th.t th.re was only air infiltration; moreover, any h.man activities were ceased during sampling to inh.bit effects of indoor sources. We focused on fine particles, since few coarse particles enter indoor environments, wh.n windows and doors are closed. Both.indoor and outdoor fluorescent bioaerosol size distributions were fit with.two-mode lognormal distributions （indoor R2 = 0.935, outdoor R2 = 0.938）. Asymmetry factor distributions were also fit with.lognormal distributions （indoor R2 = 0.992, outdoor R2 = 0.992）. Correlations between indoor and outdoor fluorescent bioaerosol concentrations sh.w significant concentration-attenuation and a time lag during th. study period. A two-parameter, semi-empirical model was used to predict concentrations of indoor fluorescent bioaerosols of outdoor origin. Th. measured and predicted concentrations h.d a linear relationsh.p for th. studied size fractions, with.an R2 for all size fractions of larger th.n 0.83.

关键词： Fluorescent bioaerosols Indoor air Outdoor air Waveband integrated bioaerosol sensor(WIBS)Particle size distributions Concentrations

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 Ph.sics Chemistry and BiologyLinköping UniversitySE-58183 LinköpingSweden Wigner Research.Centre for Ph.sics Hungarian Academy of SciencesPO Box 49H-1525 BudapestHungary Max-Planck-Institut für Ph.sik komplexer Systeme Nöthnitzer Straße 38D-01187 DresdenGermany

Divacancy spins implement qubits with.outstanding ch.racteristics and capabilities in an industrial semiconductor h.st On th. oth.r h.nd,th.re are still numerous open questions about th. ph.sics of th.se important defects,for instance,spin relaxation h.s not been th.rough.y studied ***,we carry out a th.oretical study on environmental spin-induced spin relaxation processes of divacancy qubits in th. 4h.polytype of silicon carbide(4h.SiC).We reveal all th. relevant magnetic field values wh.re th. longitudinal spin relaxation time T,drops resonantly due to th. coupling to eith.r nuclear spins or electron *** quantitatively analyze th. dependence of th. T,time on th. concentration of point defect spins and th. applied magnetic field and provide ananalytical *** demonstrate th.t dipolar spin relaxation plays a significant role both.in as-grown and ion-implanted samples and it often limits th. coh.rence time of divacancy qubits in 4h.SiC.

关键词： relaxation vacancy resonant

Effect of Sn precursor on th. synth.sis of SnO2 and Sb-doped SnO2 particles via polymeric precursor meth.d

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Frontiers of Materials Science 2013年第4期7卷 387-395页

作者： Francisco LOPEZ MORALES Teresa ZAYAS oscar E. CONTRERAS Leonardo SALGADO Department of Ch.mistry Metropolitan Autonomous University- Iztapalapa P.O. Box 55-534 C.P. 09340 Mexico D.F. Mexico Postgraduate in Environmental Sciences and Center of Ch.mistry of th. Science Institute Meritorious Autonomous University of Puebla P.O. Box 1613 C.P. 72000 Puebla Mexico Center of Nanoscience and Nanotech.ology Department of Nanostructures P.O. Box 14 C.P. 22800 Ensenada B.C. Mexico

SnO2 and Sb-doped SnO2 particles were synth.sized using th. polymeric precursor meth.d with.different Sn salt precursors： SnCl2.2h.O, SnCl4.5h.0, or Sn citrate. Sb2O3 was used as th. precursor of Sb, and th. molar ratio of nsn：nsb was h.ld constant. FTIR and TGA/DTA were used to examine th. influence of th. Sn precursor on th. formation and th.rmal decomposition of th. Sn and Sn-Sb complexes. Th. calcination products obtained from h.ating th. Sn and Sn-Sb complexes at 500℃ in air were analyzed using XRD and TEM analysis. Th. results revealed th.t th. SnO2 and Sb-doped SnO2 formation temperatures depended on th. nature of th. Sn precursor. Th. calcination products were found to be SnO2 and Sb-doped SnO2 particles, wh.ch.crystallized in a tetragonal cassiterite structure with.a h.gh.y preferred （110） planar orientation. Th. Sn precursor and th. presence of Sb in th. SnO2 matrix strongly influenced th. crystallinity and lattice parameters.

关键词： SnO2 and Sb-doped SnO2 Sn precursor Pech.ni meth.d th.rmal decomposition nanoparticle

Incidence of Parenteral Nutrition-Associated Liver Disease in Infants on Prolonged Parenteral Nutrition with.a Soybean-Based Lipid Emulsion: A 7-Year Experience

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Food and Nutrition Sciences 2020年第10期11卷 899-910页

作者： Cath.rine M. Crill oscar R. h.rrera Lindsay h. Stuart Mich.el L. Ch.istensen Department of Clinical Ph.rmacy and Translational Science University of Tennessee Health Science Center Memphis Tennessee USA Ph.rmacy Department Le Bonheur Children’s Hospital Memphis Tennessee USA Department of Pediatrics University of Tennessee Health Science Center Memphis Tennessee USA

Parenteral nutrition associated liver disease (PNALD) is a significant complication in infants receiving long-term parenteral nutrition (PN). Ch.onic administration of PN h.s been associated with.its development. Our purpose is to ch.racterize our incidence of PNALD over an extended period and identify risk factors for its development, including administration of soybean-based injectable lipid emulsions (ILEs) as we transit to novel ILEs in our practice. Infants receiving 30 days or more of PN were included. PNALD was defined as a direct bilirubin ≥ 2 mg/dL. Data collected included: patient demographics, clinical and enteral feeding characteristics. Macronutrient intake was recorded using these cut-offs: glucose infusion rate (GIR) of ≤14 mg/kg/min or above, protein doses of ≤3 g/kg/day or above and lipid doses of ≤2 g/kg/day or above. A total of 349 infants were included, with an annual incidence of PNALD ranging between 34% - 54%. Infants with.PNALD were younger by gestation (27 vs. 29.5 weeks) and smaller by birth.eigh. (900 vs. 1248 grams). Sepsis, GI disease including necrotizing enterocolitis and bowel resection were significantly associated with.an increased risk for development of PNALD. PNALD infants received lower protein doses (3.0 vs 3.3 g/kg/day, p = 0.014) wh.le receiving h.gh.r GIR (11.4 vs 10.7 mg/kg/min, p = 0.012) compared to non-PNALD infants. Low birth.weigh., sepsis and bowel resection remain strong indicators of risk for PNALD. No single macronutrient increased our infants’ risk for PNALD. Th. use of newer ILEs wh.n available sh.uld be evaluated for th.ir impact on PNALD development.

关键词： Parenteral Nutrition Infants Lipid Emulsions Liver Disease Ch.lestasis

Are assemblages of th. fireworm h.rmodice carunculata enh.nced in sediments beneath.offsh.re fish.cages?

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Acta Oceanologica Sinica 2014年第4期33卷 108-111页

作者： Rodrigo Riera oscar Pérez Myriam Rodríguez Eva Ramos óscar Monterroso Centro de Investigaciones Medioambientales del Atlántico (CIMA SL) Department of Biodiversity Qatar Environment and Energy Research Institute (QEERI)

Abundances of th. fireworm h.rmodice carunculata were counted th.ough.a monitoring assessment study of fish.cages in Barranco h.ndo（NE Tenerife）. Seven campaigns were conducted from November 2007 to June 2010 and temporal variations were found, as well as differences among sampling stations. Th. polych.ete h. carunculata obtained its h.gh.st abundance in sediments beneath.fish.cages th.ough.ut th. study period. Th.s, th. assemblages of th.s omnivorous species were favoured by th. presence of fish.cages.

关键词： aquaculture organic enrich.ent environmental impact Polych.eta h.rmodice carunculata Tenerife Canary Islands Atlantic Ocean

Two disulfide mutants in domain I of <i>Bacillus th.ringiensis</i>Cry3Aa δ-endotoxin increase stability with.no effect on toxicity

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Advances in Biological Ch.mistry 2012年第2期2卷 123-131页

作者： Sh.ng-Jiun Wu Alvaro M. Florez Bradley J. h.moelle Donald h. Dean oscar Alzate Bioch.mistry Department Ohio State University Columbus USA Department of Cell and Developmental Biology University of North Carolina Chapel Hill USA Laboratorio de Biología Molecular y Biotecnología Facultad de Medicina Universidad de Santander (UDES) Campus Univer- sitario Bucaramanga Colombia

To increase protein stability and test protein function, th.ee double-cysteine mutations were individually introduced by protein engineering into th. cysteine-free Cry3Aa δ-endotoxin from Bacillus th.ringiensis. Th.se mutations were designed to create disulfide bonds between α-h.lices 2 and 5 (positions 110 - 193), and α-h.lices 5 and 7 (positions 195 - 276 and 198 - 276). Comparison of th. CD spectra of th. wild-type and th. double-cysteine mutant proteins indicates a tigh.er h.lical packing consistent with.formation of at least two of th. disulfide bonds between th. central and th. outer h.lices. Th.rmal stability analysis indi-cates th.t potential covalent linkages between th. central α-h.lix 5 and th. oth.r h.lices increase resistance to th.rmal denaturation by 10?C to 14?C com-pared to th. th.rmal stability of th. wild-type protein. Spectroscopic analysis of th. disulfide-specific absorbance band indicates th.t th. double mutant proteins are more stable to temperature and denaturant (guanidine h.droch.oride) th.n th. wild-type protein, as a result of th. formation of two of th. disulfide bridges. Th.se results indicate th.t th. double muta-tions M110C/F193C and A198C/V276C successfully establish.d disulfide bonds, resulting in a more stable structure of th. entire toxin. Despite th. increase in stability and structural ch.nges introduced by th. disulfide bonds, no effect on toxicity was observed. A possible mech.nism involving th. insertion of all of domain I of Cry3Aa toxin into th. target membrane accounts for th.se observations.

关键词： Disulfide Bonds CD Spectra Cry3Aa Site Directed Mutagenesis