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Novelties in Campyloneurum(Polypodiaceae) from Mesoamerica

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American Journal of Plant Sciences 2017年第4期8卷 921-940页

作者： Alexander Francisco Rojas-alvarado Universidad Nacional de Costa Rica Heredia Costa Rica

Three new species are described and another is recognized in Campyloneurum. Two species occur in Mexico to El Salvador and the others two are present in Nicaragua, Costa Rica and Panama. The new species are Campyloneurum acutum A. Rojas, C. leoniae A. Rojas and C. madrense A. Rojas. The first species differs from C. xalapense by broader rhizome scales, acute to attenuate blade apex, commonly two series of areoles between parallel veins, commonly one sori per areole and hydathodes absent or few evident. Campyloneurum leoniae differs from C. irregulare by more compact and non-pruinose rhizomes, thinner stipes, relatively broader, thinner and more opaque laminae, and distribution at lower elevations. Campyloneurum madrense is different to C. angustifolium because it has narrower and darker rhizome scales with denticulate margin, long scales cells and distributed at lower elevations. Finally, Campylonerum pittieri is here recognized as valid species and it differs from the similar C. amphostenon by longer rhizomes with appressed scales that have a patent, long acuminate apices, relative broader laminae, veins evident and distribution at higher elevations.

关键词： Campyloneurum amphostenon Complex Campyloneurum angustifolium Complex Campyloneurum xalapense lectotype Designed New Species Ferns Species Recognized

Nucleation and growth kinetics of la0.7Sr0.3Cr0.4Mn0.6O3-δ SOFC perovskite:Symmetry alteration evolution induced by Cu2+ and Ni2+ impregnation

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Progress in Natural Science:Materials International 2016年第6期26卷 665-670页

作者： A.Concha-Balderrama G.Rojas-George J.alvarado-Flores H.Esparza-Ponce M.H.Bocanegra-Bernal A.Reyes-Rojas Centro de Investigación en Materiales Avanzados S.C.(CIMAV) Laboratorio Nacional de NanotecnologíaMiguel de Cervantes 120 Complejo Industrial ChihuahuaCd.de Chihuahua

la0.7Sr0.3Cr0.4Mn0.6O3-δperovskite nanoparticles have been synthetized using an ethylene glycol modified solgel method and impregnated by Cu0.75Ni0.25nanoparticles. The phase transitions and nucleation kinetics were studied by time resolved x-ray diffraction, Rietveld, raman spectroscopy and high resolution transmission electron microscopy. Findings have shown that, an atomic disorder dominates from room temperature to 400 °C. Nanoparticles with crystal size lei formation of la0.7Sr0.3Cr0.4Mn0.6O3-δand SrCrO4solid solutions with Pm3m cubic and P21/n monoclinic symmetry respectively in the range of 600–650 °C. Symmetry reduction from the Pm3m→R3c space group had been obtained at a lower temperature（750 °C） than those reported in the literature in oxygen atmosphere and it was confirmed by an octahedral distortion, which takes place in the crystallographic direction[221]/（122）. The Johnson-Mehl-Avrami model had described the whole process, where the existence of two phases was shown before it reached its complete D3d6point group symmetry.

关键词： Perovskite structure Sol-gel method Composite Kinetics Rietveld

Three New Species of Ferns (Pteridophyta) from Mesoamerica

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American Journal of Plant Sciences 2017年第6期8卷 1329-1338页

作者： Alexander Francisco Rojas-alvarado Universidad Nacional de Costa Rica Heredia Costa Rica

In this research three new species of ferns of the Polypodiales Order are described: Ctenitis leonii A. Rojas, Elaphoglossum karinae A. Rojas and Pecluma celaquensis A. Rojas. Ctenitis leonii is characterized by its apical stipe scales marginally erose to ciliate, blade surfaces with two types of hairs present in both surfaces, ones 0.7 - 1.5 mm long and not glandular, the others 0.3 - 0.5 mm long and glandular and indusia are absent. Elaphoglossum karinae differs from Elaphoglossum dissitifrons Mickel by shorter rhizome, longer and relatively narrower rhizome scales, they lanceolate to linear-lanceolate and blackish costal scales. Pecluma celaquensis is similar to Polypodium martensii Mett., but differs by its thinner rhizome, smaller rhizome scales and these with a crown of brown cilia at the attaching point, relatively shorter stipe with longer hairs and these commonly no glandular, scaly rachis and it with longer and denser hairs, inframedial sori and glabrous sporangia.

关键词： Ctenitis Elaphoglossum Honduras New Speciefs Pecluma Polypodiales

Four New Species and Additional Distributions of ElaphoglossumSection Elaphoglossum(Dryopteridaceae) from the Neotropics

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American Journal of Plant Sciences 2017年第6期8卷 1234-1247页

作者： Alexander Francisco Rojas-alvarado Universidad Nacional de Costa Rica Heredia Costa Rica

Four new species of Elaphoglossum sect. Elaphoglossum are described: E. Amparoanum A. Rojas, E. Chocoense A. Rojas, E. Fayorum A. Rojas and E. luciae A. Rojas. The first species is related to E. Variolatum Mickel, but differs from it by having rhizome scales bicolorous and long ciliate margin. The second species is different to E. moranii Mickel by having narrower rhizome, shorter stipe, elliptic blade, attenuate blade base, shorter fertile fronds with blackish costa and present at lower altitudinal distribution. After that, the third species differs from E. lingua (C. Presl) Brack. by pale rhizome scales with long ciliate margin, shorter fronds and blade scales denser and lighter. Finally, the fourth species is related to E. atrosquamatum Mickel, but with relative longer fronds and broader blade. The geographical distributions of E. guatemalense (Klotzsch) T. Moore, E. longicrure Christ, E. minutum (Pohl ex Fée) T. Moore and E. nicaragüense A. Rojas are expanded.

关键词： Dryopteridaceae Elaphoglossum Ferns New Records New Species Section Elaphoglossum Taxonomy

Bacille-Calmette-Guerin modulates human macrophage and dendritic cell response to SARS-CoV-2 S-glycoprotein

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Infectious Medicine

Infectious Medicine 2023年第3期2卷 241-245页

作者： Regina C.Ambe Shubhang Bhalla Alejandra alvarado Jose Barragan Jorge Cervantes Paul l.Foster School of Medicine Texas Tech University Health Sciences CenterEl PasoTX 79905USA Dr Kiran C.Patel College of Allopathic Medicine Nova Southeastern UniversityFort LauderdaleFL 33328USA

Background:Given that epidemiological evidence suggests a potential protective role for Bacille-Calmette-Guerin against COVID-19,we aimed to explore whether pre-exposure of human monocyte-derived macrophages and dendritic cells to BCG could modulate their response to SARS-CoV-2 ***:Dual THP-1 cells containing 2 reporter plasmids for transcription factors NF-κB,and IRF were differ-entiated into macrophages over 3 days using phorbol 12-myristate 13-acetate,or into dendritic cells over 6 days using commercial monocyte-dencritic cell differentiation media and matured with recombinant tumor necrosis factor-α.Cells were exposed to BCG for 24 h and then stimulated with SARS-CoV-2 S-glycoprotein for 24 ***:Pre-exposure of human macrophages and DCs to BCG increased IRF and NF-kb activation in response to the SARS-CoV-2 ***:Our results showed that pre-exposure of both types of cells to BCG exhibited an increase in inflam-matory transcription factors upon stimulation with ***-induced trained immunity may be an important tool for reducing susceptibility to SARS-CoV-2 infection and severity of *** findings help in the design of future BCG-based therapeutic approaches in the treatment of diseases caused by viral infections.

关键词： BCG SARS-CoV-2 Dendritic cell Macrophage

WHY NOT OTHER CEllUlAR THEra-PIES?

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国际眼科杂志 2003年第1期3卷 108-109页

作者： J.A.alvarado University Of California San Francis- co CA USA

Purpose: To determine the content of ZO- 1 isoform, hydraulic conductivity properties and formation of transendothelial fluid flow pathways or 'giant' vacuoles in cultured Schlemm's canal (SCEs) and trabecular meshwor... 详细信息

关键词：巩膜静脉穿小梁网内皮细胞 ZO-1 房水外流调节细胞类型青光眼治疗

Union of South American Nations： Monetary Synchronization and Economic Asymmetries

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Economics World 2016年第2期4卷 66-76页

作者： Sylvia Cristina alvarado Navas Free lancer Yakarta Indonesia

An analysis of the monetary synchronization of the Union of South American Nations （UNASUR） for the decade 2004 through 2013 has been conducted using the optimum currency area （OCA） theories in order to evaluate the economic integration. By applying Bayoumi and Eichengreen＇s equation, it was found that with a decent adjustment, a high percentage of countries show a tendency to harmonize their currencies in function of the four independent variables： output disturbances, the dissimilarity in exports composition, the trade linkages, and the size of the economies. To extend the model, mobility of labor and level of the integration in good＇s market were added by modifying Behrens＇ proposal, founding that the six variables are indeed related to the exchange rate harmonization at different significant levels, with a considerable moderate fitting. Additionally an analysis of variance （ANOVA） has been considered in order to study the following economic indicators： gross domestic product （GDP）, population, GDP per capita, exports to group vs. total exports, unemployment, and inflation rates so as to visualize the economic asymmetries of the Union, for the same period. Differences were inferred for all of them but not for their annual speed of change. The least significant differences （lSD） provide further results and Duncan＇s multiple range tests lead to defining groups of countries with similar characteristics.

关键词： Union of South American Nations (UNASUR) regional integration optimum currency area (OCA) multiple comparisons economic asymmetries

Integration level for the Association of Southeast Asian Nations （ASEAN） Economic Community

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Chinese Business Review 2016年第2期15卷 55-63页

作者： Sylvia Cristina alvarado Navas Free lancer Jakarta Indonesia

The time has come for the constitution of the Association of Southeast Asian Nations （ASEAN） economic community and many facts have been analyzed regarding this topic. This paper presents the results of the statistical analysis applied to several economic parameters which firstly show how their integration pattern adjusts with a considerable good fitting to the optimum currency area model and to its extended version by Behrens; and secondly how the 10 members of this group are moving at relatively same speed in spite of their differences, that are also inferred for ranging.

关键词： Association of Southeast Asian Nations (ASEAN) regional integration ASEAN members' economicdifferences and similarities currency harmonization optimum currency area (OCA)

Mantle derived crystal-poor rhyolitic ignimbrites:Eruptive mechanism from geochemical and geochronological data of the Piedra Parada caldera,Southern Argentina

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Geoscience Frontiers 2018年第5期9卷 1529-1553页

作者： Eugenio Aragon Antonio Castro Juan Diaz-alvarado lucio Pinotti Fernando D'eramo Manuel Demartis Jorge Coniglio Irene Hernando Carmen Rodriguez Centro de Investigaciones Geológicas(UNlP-CONICET) 1 N^o 644(1900)La PlataBuenos AiresArgentina Departamento de Geología Universidad de Huelva21071 HuelvaSpain Departamento de Geología Universidad de AtacamaCopayapu 485CopiapóChile Departamento de Geología Universidad Nacional de Río Cuarto(UNRC-CONICET)Ruta 36 km 601Río CuartoCórdobaArgentina

Trace elements, isotopic modeling and U-Th-Pb SHRIMP zircon age constraints are used to reconstruct the eruption history and magmatic processes of the Piedra Parada Caldera. In the early Eocene, the crystal-poor Barda Colorada ignimbrite(BCI), having >>15% micro-porphyritic crystals with respect to magmatic components, erupted a volume estimated in more than 300 km^3. The Piedra Parada caldera is located in the Patagonian Andes foreland, at the southern end of the calderas field of the Pilcaniyeu Volcanic Belt(PVB). This belt is related to an extensional tectonic setting as a result of the collision of the Farallon-Aluk ridge with South America, which enabled the development of a transform ocean/continental plate margin followed by the detachment of the Aluk plate and the opening of a slab window. The BCI extra-caldera Plateau is a >100 m thick deposit, having a lower unit with high silica(Si O_2> 76 wt.%),potassium poor rhyolitic composition(trondhjemitic like magma), and an upper unit with normal to high potassium rhyolitic composition(granitic like magma). A trace elements modeling of the BCI units shows that the BCI lower and upper units did not evolve from fractionation or immiscibility in the shallow magma reservoir. The BCI also have a primitive isotopic signature(initial87 Sr/86 Sr =0.7031-0.7049 and ε_(Nd)= +3.4 to +3.65). Thus, tectonic, compositional and isotopic constraints suggest the fast ascent of high silica magmas to a shallow reservoir, and point to an upper mantle origin for these rhyolitic magmas in a transitional(Orogenic-Anorogenic) tectono-magmatic setting. U-Th-Pb SHRIMP zircon crystallization ages of the Syn-caldera stage BCI units(56 -51.5 Ma) show a protracted life of 5 Ma for this caldera reservoir. The age of 52.9 ± 0.3 Ma is considered the best fit for the possible maximum age for the caldera collapse. The late-caldera magmatism has trachyandesitic and rhyolitic *** trace element modeling suggests that these rhyolites evolv

关键词： Mantle derived rhyolite Crystal-poor ignimbrite Bimodal volcanism Slab window volcanism K poor-rhyolite