Morphological study of the marine planktonic diatom Chaetoceros castracanei Karsten (Bacillariophyceae) from Antarctic waters, with a discussion on its possible taxonomic relationships

Phytoplankton samples were collected along the north coast of the Antarctic peninsula, the Weddell Sea and the Gerlache Strait, in different seasons in 1985, 1986, 1999, and 2000-2002. Chaetoceros castracanei Karsten, a fairly rare species was present in the sample

Dogs and Cats Put Wildlife at Risk

Populations of domestic dogs and cats are increasing worldwide and affecting ecosystems, which is especially relevant when they live near protected areas. Free- ranging dogs and cats interact with wildlife in several ways through predation, harassment, disease transmission, or hybridization. They can also compete with wildlife by reducing the availability of prey or by altering activity patterns through interference. Most of the time these interactions are negative for wildlife, which lead dogs and cats to be considered the cause ofmore than half of the global extinctions of bird, mammal, and reptile species. Regrettably, despite the fact that these effects have been studied around the world, the presence of free-ranging dogs and cats near protected areas is not perceived as an important problem for most people and policy makers. We call on the local authorities and policy makers to enforce existing laws, particularly laws to ensure that owned free-ranging dogs and cats be kept within the property limits of their homes. It is also important to develop more effective neutering programs for dogs and cats that are free of charge to reduce their populations in all urban sites surrounding protected areas. We also suggest controlling the health status of dogs and cats, especially to control parasites and reduce potential transmission to native wildlifeFil: Plaza, Pablo. 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. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Speziale, Karina Lilian. 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. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Zamora Nasca, Lucía Belén. 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. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Lambertucci, Sergio Agustin. 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. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentin

High primary productivity in an ice melting hot spot at the eastern boundary of the Weddell Gyre

The Southern Ocean (SO) plays a key role in modulating atmospheric CO 2 via physical and biological processes. However, over much of the SO, biological activity is iron-limited. New in situ data from the Antarctic zone south of Africa in a region centered at ~20°E-25°E reveal a previously overlooked region of high primary production, comparable in size to the northwest African upwelling region. Here, sea ice together with enclosed icebergs is channeled by prevailing winds to the eastern boundary of the Weddell Gyre, where a sharp transition to warmer waters causes melting. This cumulative melting provides a steady source of iron, fuelling an intense phytoplankton bloom that is not fully captured by monthly satellite production estimates. These findings imply that future changes in sea-ice cover and dynamics could have a significant effect on carbon sequestration in the SO

Association between Post-Hospitalization Psychological Distress, Exercise Capacity, Physical Function and Health Status in COVID-19 Survivors

This study aims to determine whether post-hospitalization psychological distress is associated with exercise capacity, physical function and health status in COVID-19 survivors. In this observational study, hospitalized COVID patients were included and divided into two groups according to the mental component summary subscale of the 12-item Short-Form Health Survey. Patients with a score ≤ 45 were included in the psychological distress group, and patients with a score > 45 were included in the non-psychological distress group. The main variables were exercise capacity, physical function, and health status. Patients were evaluated at discharge, 3 months, and at 6 months follow-up. Finally, a total of 60 patients were included in the study. Significant differences were found in exercise capacity, physical function, and health status (p p < 0.05). It can be concluded that COVID patients with psychological distress at hospital discharge reported worse exercise capacity, physical function and health status at hospital discharge, 3 months and 6 months follow-up

A study of the diatom-dominated microplankton summer assemblages in coastal waters from Terre Adélie to the Mertz Glacier, East Antarctica (139°E–145°E)

In January 2004 the microplankton community from the coastal waters of Terre Adélie and Georges V Land (139°E - 145°E) was studied. Results showed a diatom-dominated bloom with chlorophyll a levels averaging 0.64 µg.l-1 at 5m depth (range 0.21 - 1.57 µg.l-1). Three geographic assemblages of diatoms were identified, based on principal diatom taxa abundances. The stratified waters near the Mertz Glacier presented highest phytoplankton biomasses (0.28 - 1.57 µg Chl a.l-1 at 5m) and diatom abundances (6 507 - 70 274 cells.l-1 at 5m), but low diversity, dominated by Fragilariopsis spp. Lower biomasses (0.38 – 0.94 µg Chl a.l-1 at 5m) and abundances (394 – 9 058 cells.l-1 at 5m) were observed in the mixed waters around the Astrolabe Glacier with a diverse diatom community characterised by larger species Corethron pennatum and Rhizosolenia spp. Finally an intermediate zone between them over the shallower shelf waters of the Adélie Bank represented by Chaetoceros criophilus, where biomasses (0.21 - 0.35 µg Chl a.l-1 at 5m) and abundances (1 190 - 5 431 cells.l-1 at 5m) were lowest, coinciding with the presence of abundant herbivorous zooplankton.Pelagant, contract EV/12/30