Search

The Chilean Patagonia is characterized by extensive protected areas that encompass most of the region. Mammals are often among the priorities for these protected areas either as conservation targets (e.g., threatened species) or as threats (e.g., invasive species). Camera traps offer a cost-effective alternative to monitor these species, however baseline studies are scarce in the region. Therefore, our objective was to provide an assessment of camera-trapping detection rates for mammals that are present in protected areas of Magallanes, Chilean Patagonia. Between 2015 and 2022 we installed 278 camera traps (9,936 trap-days), distributed in seven protected areas. For each protected area, we calculated the detection rates and proportion of camera traps that detected each species. We recorded 18 mammalian species, including ten native, four domestic, and four invasive species. The culpeo fox (Lycalopex culpaeus) was the most frequently detected species, followed by invasive European hare (Lepus europaeus) and puma (Puma concolor). Endangered species like the huemul (Hippocamelus bisulcus) and southern river otter (Lontra provocax) were detected infrequently, whereas beaver (Castor canadensis) and American mink (Neogale vison) were only recorded in cameras that targeted them. From our data we suggest that generalist monitoring designs are likely to be effective for relatively common species like the culpeo fox. However, when species of interest are associated with specific features of the landscape (e.g., otters and water), other designs are needed. Based on our findings, we provide recommendations for the design of camera- trapping monitoring plans in protected areas.

Se presenta un estudio de la familia Gleicheniaceae en Argentina y Paraguay, abarcando aspectos taxonómicos, morfológicos y de distribución. Se revisaron ocho herbarios de ambos países y especímenes tipo digitales. Se analizaron y describieron los caracteres morfológicos y la escultura de las esporas. Esta familia se caracteriza por sus frondes pseudodicotómicamente divididas, con yemas ubicadas en el ángulo interno de cada división. Se registraron cuatro especies de los géneros Dicranopteris (D. flexuosa) y Sticherus (S. cryptocarpus, S. lanuginosus, S. quadripartitus). Se amplía la distribución de D. flexuosa en Argentina. Se brinda una clave para la determinación de las especies, descripciones morfológicas, breves descripciones de esporas, ilustraciones, mapas de distribución geográfica y comentarios ecológicos.

Hybrid Distribution Transformers (HDTs) offer a compelling alternative to traditional low-frequency transformers (LFTs), providing auxiliary services in addition to standard functionalities. By integrating LFTs with power converters, HDTs enhance the operational capabilities of the system. The specific configuration in which converters are connected to the transformer allows for the provision of multiple services. This can not only prevent network failures but also extend the lifespan of its components, an outcome that is highly desirable in a distribution grid. This article discusses an HDT developed to mitigate voltage fluctuations in the grid and to decrease the reactive power drawn from the secondary side of traditional LFTs. A finite-control-set model predictive control (FCS-MPC), in conjunction with linear controllers, is utilized for the effective management of the HDT converters. Two separate control loops are established to regulate voltage and reactive power on the secondary side of the transformer. Results from Hardware-in-the-Loop (HIL) testing affirm the proficiency of HDT in reducing grid voltage variations by 15% and in cutting reactive power consumption by up to 94%. The adopted control strategy and topology are demonstrated to be effective in stabilizing voltage and reactive power fluctuations while concurrently facilitating the charging of the converters’ DC link directly from the grid.

The aim of this study was to analyze the profiles of IgG subclasses in COVID-19 convalescent Puerto Rican subjects and compare these profiles with those of non-infected immunocompetent or immunocompromised subjects that received two or more doses of an mRNA vaccine. The most notable findings from this study are as follows: (1) Convalescent subjects that were not hospitalized developed high and long-lasting antibody responses. (2) Both IgG1 and IgG3 subclasses were more prevalent in the SARS-CoV-2-infected population, whereas IgG1 was more prevalent after vaccination. (3) Individuals that were infected and then later received two doses of an mRNA vaccine exhibited a more robust neutralizing capacity against Omicron than those that were never infected and received two doses of an mRNA vaccine. (4) A class switch toward the “anti-inflammatory” antibody isotype IgG4 was induced a few weeks after the third dose, which peaked abruptly and remained at high levels for a long period. Moreover, the high levels of IgG4 were concurrent with high neutralizing percentages against various VOCs including Omicron. (5) Subjects with IBD also produced IgG4 antibodies after the third dose, although these antibody levels had a limited effect on the neutralizing capacity. Knowing that the mRNA vaccines do not prevent infections, the Omicron subvariants have been shown to be less pathogenic, and IgG4 levels have been associated with immunotolerance and numerous negative effects, the recommendations for the successive administration of booster vaccinations to people should be revised.

Introducción y objetivos: Algunas especies de helechos cheilanthoideos son caracterizados por presentar adaptaciones a hábitats xéricos. Además, presentan la particularidad de enrollar sus láminas frente a condiciones de stress hídrico. Sin embargo, al retornar las condiciones ambientales óptimas las láminas se vuelven a expandir. El objetivo de este trabajo es proporcionar información morfo-anatómica de las frondes y asociar estructuras anatómicas a estos movimientos foliares. M&M: Se estudiaron mediante microscopía óptica y electrónica de barrido la morfo-anatomía de las frondes de cuatro especies: Adiantopsis radiata, Cheilanthes glauca, Doryopteris concolor, y D. pentagona. Además, se analizó la densidad de los estomas y se calculó el índice estomático. Resultados: Se observó mesófilo homogéneo en A. radiata y D. pentagona. Cheilanthes glauca y Doryopteris concolor presentaron mesófilo heterogéneo dorsiventral. Todas las especies mostraron hojas hipoestómaticas y estomas de tipo anomocítico. El índice estomático osciló entre 9,1% (A. radiata) y 14,1% (D. concolor) y el rango de densidad de los estomas fue de 39,7 (D. pentagona) y 57,8 (D. concolor). Conclusiones: El mesófilo observado en A. radiata y D. pentagona refleja la especialización para habitar ambientes mesófilos. El mesófilo heterogéneo dorsiventral de Doryopteris concolor podría ser una ventaja para su hábito epifítico facultativo. Cheilanthes glauca tiene características xeromorfas y mesomorfas, probablemente como resultado de la disponibilidad de agua en el ambiente durante las diferentes estaciones. Se propone como hipótesis que el engrosamiento de las paredes anticlinales de las células epidérmicas podría estar involucrados en los movimientos de las láminas.

Dogs on sandy beaches are a threat to shorebirds. Managing this problem requires understanding the factors that influence the abundance of dogs in these ecosystems. We aimed to determine the proportion of beaches used by dogs and the effects of human presence on dog abundance on sandy beaches of southern Chile. We conducted dog counts and recorded the presence of tracks on 14 beaches. We used zero-inflated generalized linear mixed models to determine if the number of people, number of households, and other covariates were associated with dog abundance. We detected dog tracks on all the beaches, and dog sightings on most of them. Dogs were frequently not supervised (45%) and only 13% of them were leashed. The number of people on the beach and the number of houses near the beach were positively associated with the number of dogs on beaches. Finally, when dogs co-occurred with whimbrels (Numenius phaeopus), the probability of dog harassment was high (59%). Our work reveals that human presence determines the abundance of dogs on sandy beaches. Therefore, our study suggests that any strategy aiming at reducing dog harassment of shorebirds requires changes in those human behaviors that favor the presence of free-ranging dogs at beaches.

El género Pecluma en Argentina está representado por 11 especies, la mayoría son epífitas en la región norte. Pecluma plumula se registra por primera vez para el noroeste argentino. Se presentan descripciones, sinonimias, claves para determinar las especies, ejemplares examinados, ilustraciones y mapas de distribución para cada especie. Además, se brindan comentarios taxonómicos y nomenclatura - les en aquellos casos en los se resuelven cuestiones de tipificación.

La Reserva Natural Educativa Colonia Benítez cuenta con una superficie aproximada de ocho ha, está ubicada en el departamento Primero de Mayo, en la provincia del Chaco, Argentina. Desde el punto de vista fitogeográfico, esta área protegida se localiza dentro del Distrito Chaqueño Oriental de la Provincia Chaqueña. Como objetivos de este trabajo se planteó realizar un inventario de helechos y licofitos y una clave para el reconocimiento de los taxa que crecen en esta reserva. A tal fin, se examinaron las colecciones depositadas en CTES, y se realizaron nuevas recolecciones de especímenes. Se registraron 12 géneros con un total de 17 especies, siendo Doryopteris el género mejor representado con tres especies: D. concolor, D. lorentzii y D. pentagona. El género Adiantopsis presentó dos especies (A. chlorophylla y A. tweediana), al igual que Anemia con (A. simplicior y A. tomentosa var. anthriscifolia) y Pteris (Pteris denticulata var. tristicula y Pteris vittata). Los demás géneros presentaron sólo una especie: Adiantum lorentzii, Anogramma chaerophylla, Azolla cristata, Hemionitis tomentosa, Microgramma vaccinifolia, Pityrogramma calomelanos var. calomelanos, Pleopeltis minima y Selaginella sellowii. El hábito terrícola fue el mejor representado con 12 especies, de las cuales una de ellas es rupícola y otras tres se pueden comportar como epífitos facultativos, en tanto que los estrictamente epífitos fueron representados por sólo dos especies. Azolla cristata fue la única especie acuática presente. Se presentan observaciones ecológicas y un análisis biogeográfico de las especies registradas

The name Isoetes pedersenii H.P. Fuchs (Lycophyta), a species known only from the Mburucuyá National Park, Corrientes, Argentina, is validated. Observations were carried out on herbarium material with stereoscopic, light and scanning electron microscopes. The species is described and typified. A diagnosis and discussion about its distribution and its relationship with the morphology of other species of Isoetes are provided.O nome Isoetes pedersenii H.P. Fuchs (Lycophyta) foi validado para a espécie identificada apenas no Parque Nacional de Mburucuyá, em Corrientes na Argentina. Material preservado em herbário foi avaliado com microscópios estereoscó pico, de luz branca e eletrônico de varredura. A espécie foi descrita e tipificada. Um diagnóstico e uma discussão sobre a distribuição e relação com a morfologia de outras espécies de Isoetes são relatados.

Se cita por primera vez para Argentina a Vittaria graminifolia (Vittariaceae) coleccionada en las provincias de Corrientes y Misiones. Se aporta una clave para diferenciar las dos especies de Vittaria presentes en el país, y se ilustra y describe V. graminifolia. Argyrochosma nivea var. flava (Pteridaceae), conocida para el NO y centro argentino, se registra por primera vez para el NE. Se brindan comentarios sobre la distribución y ecología de las especies mencionadas.

Se lectotipifican los nombres Ophioglossum ellipticum Hook. & Grev. y O. macrorrizum Kunze. Para justificar la elección se compararon las ilustraciones originales y especímenes de herbario. Se discuten e ilustran las lectotipificaciones

Phlebodium aureum (L.) J. Sm. se cita en su sentido estricto por primera vez en la Argentina. Se describe la especie y se ilustran sus principales caracteres morfológicos. Se discute su relación con P. areolatum (Willd.) J. Sm., la otra especie que crece en el país.Phlebodium aureum (L.) J. Sm., in strict sense, is new record for Argentina. A description of the species and its main morphological features are given. Its relationships with P. areolatum (Willd.) J. Sm., the other Argentine species is discussed.

The occurrence of Doryopteris lomariacea Kunze ex Klotzsch (Pteridaceae) is confirmed forthe first time from the province of Misiones, Argentina. The species is described and illustrated,the spores are analyzed and its ecological observations are also provided