Search results for "Seasons"
showing 10 items of 361 documents
Bacterial and phytoplankton responses to nutrient amendments in a boreal lake differ according to season and to taxonomic resolution
2011
Nutrient limitation and resource competition in bacterial and phytoplankton communities may appear different when considering different levels of taxonomic resolution. Nutrient amendment experiments conducted in a boreal lake on three occasions during one open water season revealed complex responses in overall bacterioplankton and phytoplankton abundance and biovolume. In general, bacteria were dominant in spring, while phytoplankton was clearly the predominant group in autumn. Seasonal differences in the community composition of bacteria and phytoplankton were mainly related to changes in observed taxa, while the differences across nutrient treatments within an experiment were due to chang…
Carbon Budget and Molecular Structure of Natural Organic Matter in Bank Infiltrated Groundwater
2021
Groundwater : : journal of the Association of Ground-Water Scientists and Engineers, a division of the National Ground Water Association (2021). doi:10.1111/gwat.13087
Intraguild interactions between two egg parasitoids of a true bug in semi-field and field conditions.
2014
International audience; Research on interspecific competitive interactions among insect parasitoids has often been characterized by laboratory studies in which host insects are exposed to female parasitoids of different species in various sequences and combinations. In the last years, an increasing number of studies have investigated interspecific interactions under field and semi-field conditions although just a few number of works focused on egg parasitoids. In this work, we undertook a two-year study to investigate interspecific interactions between Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), two egg para…
Sequential evolution of genotype GII.4 norovirus variants causing gastroenteritis outbreaks from 2001 to 2006 in Eastern Spain.
2008
Noroviruses are the most common cause of outbreaks of viral gastroenteritis worldwide. Norovirus outbreaks were surveyed in Catalonia and the region of Valencia (Eastern Spain) between January 2001 and December 2006 as part of the European Union funded network "Food-borne viruses in Europe". During this time the etiology and epidemiological features of 194 outbreaks of acute non-bacterial gastroenteritis were investigated and norovirus was identified as causing 169 (87.1%) of them. Molecular epidemiology of viral strains was studied by RT-PCR and sequencing part of the RNA polymerase gene in ORF1 from 153 outbreak strains. The most commonly identified norovirus genotype was GII.4 (71.9% of …
Increase in viral gastroenteritis outbreaks in Europe and epidemic spread of new norovirus variant.
2004
Background Highly publicised outbreaks of norovirus gastroenteritis in hospitals in the UK and Ireland and cruise ships in the USA sparked speculation about whether this reported activity was unusual. Methods We analysed data collected through a collaborative research and surveillance network of viral gastroenteritis in ten European countries (England and Wales were analysed as one region). We compiled data on total number of outbreaks by month, and compared genetic sequences from the isolated viruses. Data were compared with historic data from a systematic retrospective review of surveillance systems and with a central database of viral sequences. Findings Three regions (England and Wales,…
Effect of seasonality on physico-chemical and microbiological properties of nicastrese milk and artisanal cheese
2021
ABSTRACT Nicastrese is an indigenous Italian goat breed reared in the Calabria region under semi-extensive practices. From January to June, the milk yield of 400 multiparous Nicastrese goats was evaluated. In addition, tank milk and ripened cheese samples were subjected to physico-chemical and microbiological analyses with the aim to assess the effect of the seasonality on quality parameters. The volatile organic compounds profile of the ripened Nicastrese cheese samples was evaluated. Results showed that the seasonality had a significant effect on milk fat, lactose, urea, citric acid contents and acidity. Microbiological analysis of tank milk samples revealed variability among the differen…
Association of low 25-hydroxyvitamin D concentrations with elevated parathyroid hormone concentrations and low cortical bone density in early puberta…
2003
Background: Very few studies have evaluated both parathyroid hormone (PTH) and 25-hydroxyvitamin D [25(OH)D] and their effects on bone mass in children. Objective: We studied the associations of serum 25(OH)D and intact PTH (iPTH) with bone mineral content (BMC) and bone mineral density (BMD) at different bone sites and the relation between serum 25(OH)D and iPTH in early pubertal and prepubertal Finnish girls. Design: The subjects were 10‐12-y-old girls (n = 193) at Tanner stage 1 or 2, who reported a mean (± SD) dietary calcium intake of 733 ± 288 mg/d. 25(OH)D, iPTH, tartrate-resistant acid phosphatase 5b (TRAP 5b), urinary calcium excretion, BMC, areal BMD, and volumetric BMD were asses…
The lizard cerebral cortex as a model to study neuronal regeneration
2002
The medial cerebral cortex of lizards, an area homologous to the hippocampal fascia dentata, shows delayed postnatal neurogenesis, i.e., cells in the medial cortex ependyma proliferate and give rise to immature neurons, which migrate to the cell layer. There, recruited neurons differentiate and give rise to zinc containing axons directed to the rest of cortical areas, thus resulting in a continuous growth of the medial cortex and its zinc-enriched axonal projection. This happens along the lizard life span, even in adult lizards, thus allowing one of their most important characteristics: neuronal regeneration. Experiments in our laboratory have shown that chemical lesion of the medial cortex…
Questing abundance of adult taiga ticks Ixodes persulcatus and their Borrelia prevalence at the north-western part of their distribution
2020
Background Because ixodid ticks are vectors of zoonotic pathogens, including Borrelia, information of their abundance, seasonal variation in questing behaviour and pathogen prevalence is important for human health. As ticks are invading new areas northwards, information from these new areas are needed. Taiga tick (Ixodes persulcatus) populations have been recently found at Bothnian Bay, Finland. We assessed seasonal variation in questing abundance of ticks and their pathogen prevalence in coastal deciduous forests near the city of Oulu (latitudes 64–65°) in 2019. Methods We sampled ticks from May until September by cloth dragging 100 meters once a month at eight study sites. We calculated a…