Alien plant species on roadsides of the northwestern Patagonian steppe (Argentina)

The introduction of alien species represents one of the greatest threats to biodiversity worldwide. Highway construction increases the dispersal and invasion of exotic plant species. This study examined the assembly process of the plant communities to determine whether the roadsides of the Patagonian steppe represent a reservoir and dispersal source of invasive exotic species. We analyzed the composition of exotic and native species and functional groups present in the established vegetation and seed banks of roadsides and reference areas nearby. The type of dispersal of exotic and native species at the roadsides was also evaluated. Total cover and that of exotic and native species was lower at the roadsides than in the reference areas; however, at the roadsides the cover and seed abundance of exotic species was higher than that of native species. In the roadsides vegetation, native shrubs such as Acaena splendens predominated, along with exotic perennial herbs and grasses which were mainly represented by Rumex acetosella. In the seed bank the predominant species were exotic perennial herbs, also represented by R. acetosella, annual exotic species such as Epilobium brachycarpum and Verbascum thapsus, and annual native species such as Heliotropium paronychioides. No exotic shrubs were found either at the roadsides or in the reference areas. The species at the roadsides did not present a dominant type of dispersal. The abundance of exotic species at the roadsides, both in the aboveground vegetation and the seed bank, may be due to the stressful environment and the characteristics of the species themselves, such as the ability to form seed banks. This work revealed that the roadsides of the Patagonian steppe constitute reservoirs of invasive exotic species, highlighting the importance of identifying them and controlling their spread, with a view to generating ecosystem management programs.Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma.; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma.; ArgentinaFil: Rovere, Adriana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma.; Argentin

Germinación de Oenothera odorata, onagráceae ruderal endémica de Argentina

Onagraceae es una familia bien definida de plantas con flores y muy utilizada por el hombre. En Argentina posee numerosas representantes indígenas, distribuidas en 8 géneros y 75 especies, sien-do el 19% de las especies endémicas. Muchas onagráceas son ruderales y facilitan el establecimiento de especies más tardías, siendo útiles para la restauración de áreas degradadas. Dada la importancia de conocer las características de las semillas y de la germinación para su utilización en proyectos de restauración, se indagó sobre aspectos fisiológicos básicos de la germinación de Oenotheraodorata Jacq., hierba ruderal endémica de Argentina. El material se colectó de taludes y bordes de la Ruta Na-cional 40, dentro del éjido municipal de San Carlos de Bariloche, en la Provincia Fitogeográfica Patagónica. La construcción de rutas genera áreas degradadas denudadas de vegetación, donde la especie O. odorata podría utilizarse para iniciar los trabajos de revegetación y consolidar el sustrato. Se evaluó el porcentaje de germinación (G), el tiempo medio de germinación (MGT) y el tiempo hasta el inicio de la germinación (TUG) de un control (C) y de tratamientos pre-germinativos: estra-tificación húmeda fría de 45 días (CMS), escarificación mecánica con bisturí (MS). Los porcentajes de germinación fueron elevados (98% CMS, 96% MS, 93% C), solo se registraron diferencias entre CMS y C. El MGT fue menor en el tratamiento de CMS, respecto al C, pero fue similar al de MS. El TUG fue de 4 días para todos los tratamientos. En conclusión, la especie carece de mecanismos de dormición bajo las condiciones experimentales, lo que sumado al hecho de crecer en ambientes disturbados, ser endémica, y capturar metales pesados, la convierte en una especie propicia para utilizarse en trabajos de restau-ración ecológica en áreas afectadas por el transporte.The Onagraceae are a well-defined family of flowering plants much used by man. Many representatives of this group, which contains 75 species belonging to 8 genera, are indigenous to Argentina, and 19% of these are commonly found throughout the country. Many Onagraceae are ruderal and promote the subsequent establishment of other species, thus contributing to the restoration of degraded areas. Since it is important to know the characteristics of seeds to be used in restoration projects, we studied the basic germination physiology of Oenothera odorata Jacq., a ruderal plant indigenous to Argentina. Material was collected from roadsides and embankments along National highway 40 in the municipality of San Carlos de Bariloche, which lies within the Patagonian phytogeographic province. Road construction generates degraded areas where O. odorata could be used to initiate revegetation and consolidate the substrate. We evaluated percentage germination (G), mean germination time (MGT) and time till initiation of germination (TUG) of a control (C) and of the following pre-germination treatments: 45 days cold moist stratification (CMS) and mechanical scarification with a scalpel (MS). Germination percentages were high (98% CMS, 96% MS, 93% C), with differences recorded only between CMS and C. MGT was lower in the CMS treatment than the control, but similar to MS. TUG was 4 days for all treatments. In conclusion, this species lacks dormancy mechanisms under these experimental conditions, which, together with the fact that it grows in disturbed sites, is endemic, and captures heavy metals, makes it suitable for use in the ecological restoration of areas affected by transport systems.Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Caught between Empires: Pre-Famine Irish Immigrants in Santiago de Cuba, 1665-1847

This thesis examines the complex experiences of Irish immigrants in city and province of Santiago de Cuba. For some pre-Famine Irish immigrants, Cuba was an island of opportunities, and these often lay in the burgeoning sugar and coffee industries, industries that were dependant of enslaved labour and the slave-trade. Santiago de Cuba, a small city of almost no relevance to the Spanish American empire, appears as an unlikely destination for Irish migrants, but, although they were only a handful of families, their contribution is significant and under-explored. The present work examines those Irish families who settled permanently in Santiago from the 17th century until the eve of the Irish Great Famine in 1845. They are composed of two distinctive groups of Irish immigrants. The first one arrived from Spain throughout the 17th and 18th centuries. They developed a sense of symbolic Irish identity, expressed through naming practices, and had a hand in creating the élite cohort into which the immigrants of the second group inserted themselves in the early decades of the 19th century. The first group employed strategies to achieve social mobility and to maintain some degree of ethnic cohesion. They saw in marital alliances as a highly strategic practice that placed them into the local élite and into key colonial institutions in order to assimilate and integrate into their host society. By contrast, the second group was composed of a wider cohort of clearly transnational and trans-imperial adventurers. They sojourned in the United States, towards which market they focused their enterprises by creating trading firms and investing in coffee cultivation. They exploited the interstices of the Spanish and British empires, and of the United States’ “informal one”, to become some of the wealthiest planters and merchants in eastern Cuba. By 1827 these groups had merged into one élite that was politically and socially conservative, and religiously Catholic. They were fiercely pro-slavery and fervent supporters of the maintenance of the Spanish colonial status quo. The arguments made in this work are sustained in primary sources such as letters, genealogical data, parish records, business letters, and diplomat’s dispatches, among others. These sources were found in archival collections in Cuba, Ireland, the United Kingdom, the United States, and Spain

Alien plant species on roadsides of the northwestern Patagonian steppe (Argentina)

The introduction of alien species represents one of the greatest threats to biodiversity worldwide. Highway construction increases the dispersal and invasion of exotic plant species. This study examined the assembly process of the plant communities to determine whether the roadsides of the Patagonian steppe represent a reservoir and dispersal source of invasive exotic species. We analyzed the composition of exotic and native species and functional groups present in the established vegetation and seed banks of roadsides and reference areas nearby. The type of dispersal of exotic and native species at the roadsides was also evaluated. Total cover and that of exotic and native species was lower at the roadsides than in the reference areas; however, at the roadsides the cover and seed abundance of exotic species was higher than that of native species. In the roadsides vegetation, native shrubs such as Acaena splendens predominated, along with exotic perennial herbs and grasses which were mainly represented by Rumex acetosella. In the seed bank the predominant species were exotic perennial herbs, also represented by R. acetosella, annual exotic species such as Epilobium brachycarpum and Verbascum thapsus, and annual native species such as Heliotropium paronychioides. No exotic shrubs were found either at the roadsides or in the reference areas. The species at the roadsides did not present a dominant type of dispersal. The abundance of exotic species at the roadsides, both in the aboveground vegetation and the seed bank, may be due to the stressful environment and the characteristics of the species themselves, such as the ability to form seed banks. This work revealed that the roadsides of the Patagonian steppe constitute reservoirs of invasive exotic species, highlighting the importance of identifying them and controlling their spread, with a view to generating ecosystem management programs.Fil: Chichizola, Giselle Ailin. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Chichizola, Giselle Ailin. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio Ecotono; Argentina.Fil: Chichizola, Giselle Ailin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Gonzalez, Sofía Laura. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Gonzalez, Sofía Laura. Centro Regional Universitario Bariloche. Laboratorio Ecotono; Argentina.Fil: Gonzalez, Sofía Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Rovere, Adiana. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Rovere, Adiana. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio Ecotono; Argentina.Fil: Rovere, Adiana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Debye frequency-extended waveguide permittivity extraction for high complex permittivity materials. Concrete setting process characterization

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.A waveguide with central frequency 868 MHz is used in transmission/reflection operation regime to accurately measure the behaviour of the complex permittivity of high complex permittivity granular materials and it has been frequency-extended up to 3 GHz using the Debye fitted relaxation model. It is shown that for highly granular high permittivity materials a waveguide based transmission/reflection technique is necessary to reduce the uncertainty of the extracted permittivity values. The technique is first described and validated with isopropyl alcohol and then applied to the characterization of cement based materials. This paper provides accurate data on the evolution of the complex permittivity of concrete and mortar from the moment of pouring until air dried condition is achieved.Peer ReviewedPostprint (author's final draft

Power-Invariant Magnetic System Modeling

In all energy systems, the parameters necessary to calculate power are the same in functionality: an effort or force needed to create a movement in an object and a flow or rate at which the object moves. Therefore, the power equation can generalized as a function of these two parameters: effort and flow, P = effort * flow. Analyzing various power transfer media this is true for at least three regimes: electrical, mechanical and hydraulic but not for magnetic. This implies that the conventional magnetic system model (the reluctance model) requires modifications in order to be consistent with other energy system models. Even further, performing a comprehensive comparison among the systems, each system's model includes an effort quantity, a flow quantity and three passive elements used to establish the amount of energy that is stored or dissipated as heat. After evaluating each one of them, it was clear that the conventional magnetic model did not follow the same pattern: the reluctance, as analogous to the electric resistance, should be a dissipative element instead it is an energy storage element. Furthermore, the two other elements are not defined. This difference has initiated a reevaluation of the conventional magnetic model. In this dissertation the fundamentals on electromagnetism and magnetic materials that supports the modifications proposed to the magnetic model are presented. Conceptual tests to a case study system were performed in order to figure out the network configuration that better represents its real behavior. Furthermore, analytical and numerical techniques were developed in MATLAB and Simulink in order to validate our model. Finally, the feasibility of a novel concept denominated magnetic transmission line was developed. This concept was introduced as an alternative to transmit power. In this case, the media of transport was a magnetic material. The richness of the power-invariant magnetic model and its similarities with the electric model enlighten us to apply concepts and calculation techniques new to the magnetic regime but common to the electric one, such as, net power, power factor, and efficiency, in order to evaluate the power transmission capabilities of a magnetic system. The fundamental contribution of this research is that it presents an alternative to model magnetic systems using a simpler, more physical approach. As the model is standard to other systems' models it allows the engineer or researcher to perform analogies among systems in order to gather insights and a clearer understanding of magnetic systems which up to now has been very complex and theoretical

Bees visiting squash (Cucurbita moschata Duchesne ex Poiret) in southwestern Colombia (Hymenoptera: Apoidea)

This is the publisher's version, also available electronically from https://journals.ku.edu/index.php/melittology/article/view/4582.This note records for the first time 12 bee species belonging to eight genera of Apidae and Halictidae as visitors of cultivated squash (Cucurbita moschata Duchesne ex Poiret: Cucurbitaceae) in the municipality of El Patía, Department of Cauca, southwestern Colombia. Two further bee species are also recorded from a crop visited in the Department of Huil

Seed germination of Phacelia secunda (Boraginaceae) and Eryngium paniculatum (Apiaceae), perennial herbs from Patagonia Argentine

El objetivo fue evaluar los requerimientos de germinación de Phacelia secunda J.F. Gmel. y Eryngium paniculatum Cav. y Dombey ex F. Delaroche, herbáceas perennes colonizadoras de ambientes degradados del noroeste patagónico argentino y de interés para la restauración ecológica. Se evaluó el porcentaje, tiempo medio e inicio de germinación en un control (C) y dos tratamientos pre-germinativos: escarificación mecánica con bisturí (EM) y estratificación húmeda fría durante 45 días (EHF). En P. secunda, el porcentaje de germinación en el tratamiento EHF (2%) fue menor que en el C (24%) y el tratamiento EM (16%). En E. paniculatum se encontraron diferencias entre el C (94%) y el tratamiento EHF (82%), pero no entre el C y EM (91%). El tratamiento EHF aceleró el inicio de la geminación en ambas especies. Las semillas de P. secunda mostraron baja capacidad de germinación siendo necesario evaluar nuevos tratamientos. Eryngium paniculatum mostró alta capacidad germinativa aún en el control, lo que evidencia que no requiere tratamientos pregerminativos específicos.The aim was to evaluate the seed germination requirements of Phacelia secunda J.F. Gmel. and Eryngium paniculatum Cav. y Dombey ex F. Delaroche, perennial herbaceous colonizers of degraded environments of northwest Argentinian Patagonia and of interest for ecological restoration. The germination percentage, mean germination time and time until initiation of germination of a control (C) and two pre-germination treatments: Mechanical scarification with a scalpel (EM) and 45 days cold moist stratification (EHF) were evaluated. In P. secunda, the germination percentage in EHF treatment (2%) was lower than in C (24%) and EM (16%) treatment. In E. paniculatum, differences between C (94%) and EHF (82%) were found, but not between C and EM (91%). EHF treatment accelerated the germination initiation in both species. Seeds of P. secunda showed low germination capacity being necessary to evaluate new treatments. Eryngium paniculatum showed high germination capacity in the control. Thus this species does not require specific pre-germination treatments.Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Caracterización estructural de lodos pos-consumo como agregados en materiales de construcción

The present work covers the physical, mechanical and chemical characterization of pozzolanic materials. The pozzolans were obtained by mixing red clay, commercial bentonite and residual aluminous sludge, from a drinking water treatment plant. Ceramic cubes were manufactured, which were sintered at 1100°C and subsequently, were structurally characterized by DRX, SEM and EDS. Its compressive strength was also evaluated before and after being subjected to different environments. The results showed that the relations with which the standards for nonstructural bricks according to NTC 4017 (100 Kgf/cm2) are maintained are those that contain 10%, 20% and 30% of mud with respect to the clay maintaining an aggregate of bentonite 10% with resistances of 123.62 Kgf /cm2, 112.90 Kgf /cm2 and 107.32 Kgf / cm2, respectively. Likewise, for units exposed to corrosive environments, the 10% replacement mixture is the only one that meets the criteria established by the standard with a resistance of 112,80 Kgf/cm2 and in abrasive environments mixtures of 10% and 20% with resistance of 116,75 Kgf/cm2 and 101,96 Kgf/cm2 respectively.El presente trabajo abarca la caracterización física, mecánica y química de materiales puzolánicos. Las  puzolanas  fueron  obtenidas  por  la  mezcla  de  arcilla  roja,  bentonita  comercial  y  lodos  aluminosos residuales, provenientes de una planta de tratamiento de agua potable. Se fabricaron cubos cerámicos, los cuales fueron sinterizados a 1100 °C y posteriormente, fueron caracterizados estructuralmente por DRX, SEM y EDS. También se evaluó su resistencia a la compresión antes y después de ser sometidos a diferentes ambientes. Los resultados demostraron que las relaciones con las cuales se mantienen los estándares para ladrillos no estructurales según la NTC 4017 (100 Kgf/ cm2) son los que contienen 10%, 20% y 30% de lodo respecto a la arcilla manteniendo un agregado de bentonita del 10 % con resistencias de 123,62 Kgf/cm2, 112,90 Kgf/cm2 y 107,32 Kgf/cm2,  respectivamente.  Así  mismo  para  las  unidades  expuestas  a  ambientes  corrosivos  la  mezcla con sustitución del 10% es la única que cumple el criterio establecido por la norma con una  resistencia  de  112,80  Kgf/cm2  y  en  ambientes  abrasivos  las  mezclas  de  10%  y  20%  con  resistencias de 116,75 Kgf/cm2 y 101,96 Kgf/cm2 respectivamente