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Abstract Fire and grazing are important factors in the regulation of the grassland structure of the Flooding Pampa (Buenos Aires Province, Argentina dominated by Paspalum quadrifarium plants (henceforth ‘pajonal’)). Winter burning of pajonal is a practice that increases P. quadrifarium growth and its nutritious value for cattle. The objective of this work was to determine the responses of different demographic variables of P. quadrifarium growing in a grassland managed with different fire frequencies. The work was carried out in a pajonal situated in San Ignacio (Ayacucho county, Buenos Aires Province, Argentina). The treatments were: high fire frequency (0.8 fires per year) and low fire frequency (0.4 fires per year). The population of P. quadrifarium was affected by fire frequency. Biomass, number of tillers, and the relative production of tillers per plant did not change with fire frequency. Plant height was negatively affected by fire frequency. Whereas no plant mortality was observed in high fire frequency, 30% of the mature plants died at the end of the experiment in low fire frequency. In both treatments, plant mortality was size-dependent and juvenile plants were more affected than mature ones. Burning had an immediate negative effect on mature and juvenile plants in terms of fecundity, survival of tillers and basal cover. Tiller survival and fecundity were significantly lower in burned plants than in unburned ones. In the high fire frequency treatment the number of ramets and/or genets and basal cover were greater than in the low fire frequency treatment. [ABSTRACT FROM AUTHOR]

For several decades a variety of geophysical surveys have been carried out in the Scotia Sea, but earthquake seismology began to be widely employed only during the 1990s when some instruments were installed in the area following the activation of a temporary broadband seismographic station (ESPZ) by a team of Italian and Argentinean researchers, of the Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS) and of the Instituto Antártico Argentino (IAA) respectively, at the Antarctic Argentinean permanent base, Base Esperanza. At the beginning of 1995 ESPZ became the first permanent observatory of the Antarctic Seismographic Argentinean-Italian Network (ASAIN). In this paper, we describe the chronological and technical evolution of the ASAIN, that is financially supported by the Italian Programma Nazionale di Ricerche in Antartide (PNRA) and by the Argentinean Dirección Nacional del Antártico (DNA) and that consists today of five stations installed in Antarctica (ESPZ, JUBA, ORCD, SMAI, BELA) and two in the Argentinean Tierra del Fuego (DSPA, TRVA). The SMAI and BELA stations, both located beyond the Antarctic Polar Circle, were activated between February 2007 and January 2009 as a PNRA/OGS - DNA/IAA contribution to Antarctic Seismology during the International Polar Year. A resume of the scientific results obtained using ASAIN data is also included. [ABSTRACT FROM AUTHOR]

Mycobacterium bovis and Mycobacterium avium are the most important Mycobacteria isolated from diseased dogs, but Mycobacterium tuberculosis can be isolated as well, especially when close contact with humans exists. Free ranging street dogs may carry zoonotic diseases, being a potential health risk to new owners after adoption. In this study, the clinical case of a dog affected by Mycobacterium tuberculosis is described. A six-year-old bitch that had been living with a homeless man was rescued and put for adoption in dog shelter. After being adopted, her health declined, and abdominal ultrasound and exploratory laparoscopy were performed. A tuberculosis-like lesion in the liver was biopsied and histopathological, bacteriological, and molecular analyses were carried out. Then, the animal was euthanized and necropsied, and disseminated macroscopic tuberculosis-like lesions were observed in abdominal organs. Mycobacterium presence was confirmed by histopathological and bacteriological methods. Genotyping identified a SIT-1228 Mycobacterium tuberculosis strain. Notification to the sanitary authorities was performed and the couple that had contact with the dog were alerted and sent to the hospital for assessment, as Mycobacterium tuberculosis is a primary pathogenic agent for humans. The epidemiology in this clinical case is unclear, but the most likely source of infection might have been consumption of sputum contaminated food during the years that this bitch lived with the homeless man, because this person had died with chronic respiratory symptoms. Veterinarians must consider this disease and perform a complete diagnosis when dogs that used to live on the streets show nonspecific clinical signs., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Our study was conducted to further investigate the single-dose approach of hepatitis A vaccination, while providing supportive data on the flexibility of booster administration. Participants received at least one dose of Avaxim 80U Pediatric at 11-23 months of age, and they will be followed for 10 years. We report here the fourth and fifth years after the first vaccination. Group assignment was based on whether the children received 1 dose and no booster during the study (Group 1) or 2 doses and no further booster (Group 2). Anti-HAV antibody concentrations were assessed at each annual visit. Of the 546 initial participants, 441 (80.8%) and 412 (75.5%) were followed up 4 and 5 years after vaccination, respectively. Of the 411 subjects evaluable at Year 5, 318 had received one vaccine dose and 85 had received two. Seroprotection rates were still high in Group 1 (99.7%) and in Group 2 (100%) 5 years after one or two doses of Avaxim 80U Pediatric, correspondingly. Anti-HAV geometric mean concentrations decreased in both groups compared to what they were 3 years after vaccination, while remaining well above the 10 mIU/mL threshold 5 years after vaccination. The highest concentrations were found in the children who received 2 vaccine doses. Hepatitis A humoral immunity induced by a single dose of inactivated hepatitis A vaccine can persist for at least 5 years in a paediatric population. The study results also support recommendations in favour of a flexible time window for booster vaccination., (© 2014 The Authors. Journal of Viral Hepatitis Published by John Wiley & Sons Ltd.)