Cambios estacionales en los ensambles de aves en un ecotono bosque-estepa del norte de Patagonia

Estudiamos las variaciones estacionales en una comunidad de aves que habitan el ecotono bosque-estepa del norte de Patagonia. Analizamos los cambios en la riqueza de especies, la composición de especies y la abundancia total, y a nivel de las especies, evaluamos las diferencias en la estacionalidad reproductiva y de muda. El ensamble de aves mostró pocas variaciones estacionales en la riqueza y abundancia total, pero un notable cambio en la composición de especies entre la primavera–verano y el otoño–invierno. El cambio en la composición de especies no promovió variaciones estacionales en la riqueza y la abundancia total, debido a la presencia de especies abundantes que visitan el área en las diferentes estaciones. A nivel de las especies, las aves residentes y migrantes de corta distancia tendieron a comenzar la reproducción antes que las migrantes de larga distancia, y aquellas especies de aves comenzaron la muda de plumas del cuerpo y del ala al finalizar la reproducción. Por lo cual encontramos una baja superposición de estas dos demandantes actividades. Elaenia albiceps, la única especie migradora de larga distancia, no presentó muda corporal o del plumaje de vuelo en nuestra área de estudio. Nuestros resultados remarcan la importancia del movimiento de las aves en respuesta a las variaciones en la disponibilidad de recursos, que promueven la migración o el desplazamiento local de las aves.We studied seasonal variation in a community of birds inhabiting a forest?steppe ecotone of north Patagonia. We analyzed changesin species richness, species composition and total abundance, and, at the species level, we evaluated differences in breeding and moltingseasonality. The bird assemblage showed a low seasonal variation in richness and total abundance, but a great change in species compositionbetween spring?summer and fall?winter. The change in species composition did not lead to changes in richness and total abundance, due tothe presence of abundant species that visit the area in different seasons. At the species level, resident birds and short distance migrantstended to begin breeding earlier than long distance migrants, and those bird species began to molt body and flight feathers after breeding.Therefore, we found a low overlap between these two energetically demanding activities. Elaenia albiceps, the only long-distance migrantspecies, did not molt body and flight feathers in our study area. Our results highlight the importance of bird movements in response to seasonalvariations in the availability of resources, which promote migration or local displacements of birds.Fil: Cueto, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Gorosito, Cristian Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentin

Beak deformities in north Patagonian birds

Within the last decade, many individuals of several bird species with abnormal and strange beaks deformationshave been reported from Alaska, United States, and from United Kingdom and Ireland. Different forms of beakdeformities were observed, but the causes of these abnormalities are unknown. We report beak deformities in twospecies of birds in northwestern Patagonia, Argentina: Austral Thrush (Turdus falcklandii) and Patagonian Mockingbird(Mimus patagonicus). Between 2013 and 2016, we captured individuals of White‐crested Elaenia (Elaenia albiceps, N= 305), Rufous‐collared Sparrow (Zonotrichia capensis, N = 119), Austral Thrush (N = 100), Black‐chinned Siskin (Spinusbarbata, N = 64), Patagonian Sierra‐Finch (Phrygilus patagonicus, N = 48) and Gray‐hooded Sierra‐Finch (Phrygilusgayi, N = 40) in surroundings of Esquel city, located in western Patagonia, Chubut province, and quantified the prevalenceof beak deformities. Only adult Austral Thrushes (5 out of 78; 6.41%) showed abnormal beaks. Neither juvenilethrushes (N = 22) nor the other five species showed beak deformations. Austral Thrushes with beak deformationswere also observed and photographed (but not captured) in other areas around the city. We also photographed onePatagonian Mockingbird with an abnormal beak near Las Plumas Village, Chubut province. Beak deformities variedfrom light to severe, and also in their form. Most of them were characterized by an elongated and often decurvedupper mandible, producing an overbite; in other individuals both mandibles were elongated and sometimes crossedor had a pronounced gap. Most affected birds showed signs of improper preening, and one of them was malnourished.All of these characteristics are similar to those described for birds affected by avian keratin disorder in NorthAmerica. Further research is needed to detect potential presence of other species with beak deformities in Patagonia,to find out possible causes of such deformities, and to determine whether these anomalies are associated with naturalhabitats or urban environments.Fil: Gorosito, Cristian Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Gonda, Héctor Eduardo. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "san Juan Bosco". Facultad de Ingeniería - Sede Esquel; ArgentinaFil: Cueto, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentin

Fruit abundance may fine-tune timing of reproduction of the Chilean Elaenia (Elaenia chilensis), a long-distance migratory bird in South America

Timing of reproduction has a great impact on the breeding success of birds because a mismatch with the moment when environmental conditions are warm or when food is most plentiful can reduce nestling survival and increase the energetic cost of parental care. Consequently, birds synchronize gonadal maturation with the most favourable environmental conditions, using photoperiod changes throughout the year as an initial proximal cue. Additionally, non-photic cues, such as temperature and food abundance, may be necessary to fine-tune reproductive timing. However, the influence of non-photic cues on finely tuning reproductive timing is not yet fully understood for migratory birds. Here, we evaluate how much non-photic cues influence the reproductive timing of the Chilean Elaenia Elaenia chilensis, a long-distance migrant that reproduces in the Andean–Patagonian Forest. We assessed associations of mean temperature, ripe fruit and arthropod abundances with the number of nests in the laying period, and also with the number of nests with hatchlings. In both analyses we used cross-correlations and partial least squares path modelling. Mean temperature was not consistently associated with the breeding phenology of Chilean Elaenias. The increase in number of nests in the laying period was preceded by the increase in caterpillar abundance and coincided with the increase in ripe fruit abundance. The timing of nests with hatchlings matched with the timing of highest ripe fruit abundance. Both types of food could contribute to the beginning of reproduction of birds and be used as proximal cues by Chilean Elaenias. Ripe fruits would also be beneficial for nestling growth because parents feed them with fruits, and might potentially play an ultimate role in reproduction. Because ripe fruit abundance was related to the egg-laying and hatching stages, it may be the main cue used by Chilean Elaenias to fine-tune reproductive timing. These findings allow advances in our understanding of the importance of non-photic cues in the reproductive phenology of migratory birds and also generalize our knowledge among regions and taxa, as most studies on this topic focus on the Northern Hemisphere.Fil: Gorosito, Cristian Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Tuero, Diego Tomas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Cueto, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentin

Are all patches worth exploring? Foraging desert birds do not rely on environmental indicators of seed abundance at small scales

Background: Consumers should show strong spatial preferences when foraging in environments where food availability is highly heterogeneous and predictable. Postdispersal granivores face this scenario in most arid areas, where soil seed bank abundance and composition associates persistently with vegetation structure at small scales (decimetres to metres). Those environmental features should be exploited as useful pre-harvest information, at least to avoid patches predicted to be poor. However, we did not find the expected spatial association in the algarrobal of the central Monte desert by observing foraging seed-eating birds, a field technique influenced by how much they exploit visited patches. In this work we tested if the first stage of foraging by granivorous birds (patch visit, encounter or exploration) is positively associated with environmental indicators of patch quality by recording the removal of single seeds from 300 scattered experimental devices during seasonal trials. Spatial selectivity was analysed by comparing the structural characteristics of used vs. available microhabitats, and evaluated against bottom-up and top-down hypotheses based on our previous knowledge on local seed bank abundance, composition and dynamics. Their foraging activity was also explored for spatial autocorrelation and environmental correlates at bigger scales. Results: Postdispersal granivorous birds were less selective in their use of foraging space than expected if microhabitat appearance were providing them relevant information to guide their search for profitable foraging patches. No microhabitat type, as defined by their vegetation structure and soil cover, remained safe from bird exploration. Analyses at bigger temporal and spatial scales proved more important to describe heterogeneity in seed removal. Conclusions: Closeness to tall trees, probably related to bird territoriality and reproduction or to their perception of predation risk, seemed to determine a first level of habitat selection, constraining explorable space. Then, microhabitat openness (rather than seed abundance) exerted some positive influence on which patches were more frequently visited among those accessible. Selective patterns by birds at small scales were closer to our predictions of a top-down spatial effect, with seed consumption creating or strengthening (and not responding to) the spatial pattern and dynamics of the seed bank.Fil: Milesi, Fernando Adrian. 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; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; ArgentinaFil: Lopez de Casenave, Javier Nestor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; ArgentinaFil: Cueto, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia San Juan Bosco. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentin

Port-metriplectic neural networks: thermodynamics-informed machine learning of complex physical systems

We develop inductive biases for the machine learning of complex physical systems based on the port-Hamiltonian formalism. To satisfy by construction the principles of thermodynamics in the learned physics (conservation of energy, non-negative entropy production), we modify accordingly the port-Hamiltonian formalism so as to achieve a port-metriplectic one. We show that the constructed networks are able to learn the physics of complex systems by parts, thus alleviating the burden associated to the experimental characterization and posterior learning process of this kind of systems. Predictions can be done, however, at the scale of the complete system. Examples are shown on the performance of the proposed technique.Comment: 9 pages, 5 figure

L925I Mutation in the Para-Type Sodium Channel Is Associated with Pyrethroid Resistance in Triatoma infestans from the Gran Chaco Region

Background:Chagas' disease is an important public health concern in Latin America. Despite intensive vector control efforts using pyrethroid insecticides, the elimination of Triatoma infestans has failed in the Gran Chaco, an ecoregion that extends over Argentina, Paraguay, Bolivia and Brazil.The voltage-gated sodium channel is the target site of pyrethroid insecticides. Point mutations in domain II region of the channel have been implicated in pyrethroid resistance of several insect species.Methods and Findings:In the present paper, we identify L925I, a new pyrethroid resistance-conferring mutation in T. infestans. This mutation has been found only in hemipterans. In T. infestans, L925I mutation occurs in a resistant population from the Gran Chaco region and is associated with inefficiency in the control campaigns. We also describe a method to detect L925I mutation in individuals from the field.Conclusions and Significance:The findings have important implications in the implementation of strategies for resistance management and in the rational design of campaigns for the control of Chagas' disease transmission.Facultad de Ciencias Exacta

L925I Mutation in the Para-Type Sodium Channel Is Associated with Pyrethroid Resistance in Triatoma infestans from the Gran Chaco Region

Background:Chagas' disease is an important public health concern in Latin America. Despite intensive vector control efforts using pyrethroid insecticides, the elimination of Triatoma infestans has failed in the Gran Chaco, an ecoregion that extends over Argentina, Paraguay, Bolivia and Brazil.The voltage-gated sodium channel is the target site of pyrethroid insecticides. Point mutations in domain II region of the channel have been implicated in pyrethroid resistance of several insect species.Methods and Findings:In the present paper, we identify L925I, a new pyrethroid resistance-conferring mutation in T. infestans. This mutation has been found only in hemipterans. In T. infestans, L925I mutation occurs in a resistant population from the Gran Chaco region and is associated with inefficiency in the control campaigns. We also describe a method to detect L925I mutation in individuals from the field.Conclusions and Significance:The findings have important implications in the implementation of strategies for resistance management and in the rational design of campaigns for the control of Chagas' disease transmission.Facultad de Ciencias Exacta

Diagnostics and modeling of cold laboratory plasmas with high hydrogen content; applications to molecular astrophysics.

First General Meeting in Prague, May 25 - 29, 2015; http://prague2015astrohistory.vscht.cz/Cold plasmas of molecular precursors produced in low pressure glow discharges involve intricate mechanisms of great interest in many scientific and technological fields, such as thin film growth, surface conditioning and so on. In particular, hydrogen containing cold plasmas are currently used in microelectronic devices production, can simulate the border conditions of plasmas generated in fusion reactors, and are efficient sources of very reactive radicals and ions, whose study contributes to clarify the appearance of complex compounds in different regions of interstellar molecular clouds or in Jovian planet ionospheres. In this work, low pressure glow discharges of mixtures of hydrogen with simple molecules and atoms and different isotopic compositions are experimentally diagnosed, and the main mechanisms controlling their behavior are elucidated by kinetic modeling. According to theoretical predictions supported by experimental data, the formation of new molecular species takes place mainly at the reactor surfaces and competes with the fast wall recycling of the precursors, which are previously dissociated by electron impact. On the other hand, the ion distributions result mainly from the balance between electron impact ionizations, which depend markedly on electron energies, and ion-molecule reactions in gas phase, for which the proton affinity of the different neutral species plays a key role. The first detection of the deuterated ammonium ion (NH3D+) in the interstellar medium [1,2], and the refined infrared spectroscopic characterization of the isotopomers 36ArH+ and 36ArH+ [3], the first noble gas molecules found in space [4,5], exemplify the successful interaction between plasma spectroscopy and astronomical observations.The authors acknowledge the financial support from the Spanish MINECO through grants SD2009-00038, FIS2012- 38175 and FIS2013-48087-C2-1-P. Additional funding from ERC-2013-Syg 610256-NANOCOSMOS is also aknowledged.Peer Reviewe

Does e-assessment always fit digital natives? A within-subject comparison between paper- and tablet-based gambling assessments in adolescents

Technological development has enabled the use of sophisticated methods for assessing multiple human behaviors. Despite the advantages of these new technologies, concerns exist regarding their equivalence with paper-based measures in epidemiological and health-related surveys. To date, literature on this topic in relation to adolescents is virtually nonexistent. This study compares respondents’ performance on the same survey using both paper- and electronic tablet- based assessment methods. A final sample of 135 adolescents (mean age 17.30 years, SD = 0.59; 56.3% males) consecutively completed two versions of the same survey on gambling behaviors and two questionnaires: The Gambling Motives Questionnaire (GMQ) and the South Oaks Gambling Screening-Revised for Adolescents (SOGS-RA). An ad-hoc questionnaire assessing participants’ satisfaction levels with each method was also used. The digital survey yielded a lifetime, past year, and past month gambling prevalence of 54.1%, 45.2%, and 27.4%, respectively. Paper-based prevalence rates were 3.7-5.2% lower (all p >.092) and there were discrepancies in gambling activities. Although the reliability of the questionnaires was high in both formats, total scores were consistently higher in the paper-based format. GMQ and SOGS-RA intraclass correlations between versions ranged from .856-.884. Unexpectedly, students preferred the paper-based survey to the e-assessment (51.5% vs. 48.5%) and also enjoyed it more (31.3% vs 26.1%). Paper- and tablet-based surveys yield different, albeit non-statistically significant, estimations of gambling behaviors even when the same participants were surveyed at one time. We recommend that consistency be routinely checked across assessment formats when adapting paper-and-pencil measures to digital formats¿La evaluación electrónica siempre se adapta a los nativos digitales? Una comparación intra-sujeto de la evaluación del juego de azar entre papel y tabletas electrónicas en adolescentes. El desarrollo tecnológico ha permitido el uso de métodos sofisticados de evaluación de múltiples comportamientos humanos. A pesar de los avances de estas nuevas tecnologías, existen preocupaciones sobre su equivalencia con las medidas de papel y lápiz en encuestas epidemiológicas y de salud. Hasta la fecha, la literatura en el tema en relación con los adolescentes es prácticamente inexistente. Este estudio compara el desempeño de los participantes sobre la misma encuesta utilizando métodos de evaluación de papel y lápiz y electrónicos. Una muestra de 135 adolescentes (edad media 17.30 años, DT = 0.59; 56.3% hombres) completaron consecutivamente os versiones de la misma encuesta sobre conductas de juego y dos cuestionarios: el Cuestionario de Motivos de Juego (GMQ) y el Cribado de Juego de South Oaks en su versión revisada para adolescentes (SOGS-RA). También se utilizó un cuestionario ad-hoc para evaluar el nivel de satisfacción de los participantes en cada método. La encuesta digital arrojó una prevalencia de juego vida, año y mes de 54,1%, 45,2%, y 27,4%, respectivamente. Las prevalencias en papel fueron 3,7-5,2% menores (todas p >,092) y se mostraron discrepancias en las actividades de apuestas. A pesar de que la fiabilidad de los cuestionarios fue alta en ambos formatos, las puntuaciones totales fueron consistentemente más altas en el formato en papel. Las correlaciones intraclase en el GMQ y SOGS-RA oscilaban entre ,856 - ,884. Inesperadamente, los estudiantes preferían la encuesta en papel sobre el formato digital (51,5% vs. 48,5%) y también lo disfrutaron más (31,3% vs 26,1%). La encuesta en papel y en tableta electrónica mostraron estimaciones diferentes, aunque no estadísticamente significativas, en las conductas de juego, incluso a pesar de haber sido encuestados en el mismo momento. Recomendamos comprobar de manera rutinaria la consistencia entre formatos de evaluación cuando se adapten medidas de papel y lápiz a formato digita