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Food and Environmental Virology - To observe the prevalence of contamination by hepatitis A virus (HAV) and norovirus (NoV) in different food types, 9242 samples were analyzed over a 6-year period...  相似文献   
93.
Seasonal differences in the locomotor activity pattern of Podarcis sicula held in constant conditions in the laboratory were found to be associated with systematic differences in both the freerunning period of locomotor rhythms () and the circadian activity time (). In order to establish whether the pineal played a role in the control of seasonal changes in circadian parameters, we examined the effects of pinealectomy in constant conditions on the locomotor behavior of lizards displaying the bimodal activity pattern typical of summer. In most lizards pinealectomy lengthened , shortened and abolished the bimodal activity pattern. Pinealectomy induced a sudden transition from the typical locomotor behavior of summer, characterized by a marked bimodal pattern, short and long , to the typical locomotor behavior of autumn, characterized by a unimodal pattern, a long and short . These results demonstrate that the pineal plays a central role in the seasonal reorganization of the circadian system that occurs in P. sicula.  相似文献   
94.
This study evaluated the presence and seasonal distribution of polio and other enteroviruses in four wastewater treatment plants in three cities in Italy, using different treatment systems. Detection of enteroviruses was carried out by virus isolation in cell cultures after concentration of water samples collected at both inlet and outlet of the treatment plants, following the methods described in the WHO guidelines. Viral serotypes isolated before and after water treatment were compared. Forty-eight non-polio enteroviruses were isolated from 312 samples collected at the inlet of the four wastewater treatment plants, 35 of which were Coxsackievirus type B (72.9 %) and 13 Echovirus (27.1 %). After treatment, 2 CVB3, 1 CVB5, and 1 Echo 6 were isolated. CVB3 and Echo 6 serotypes were also detected in samples collected at the inlet of the TP, in the same month and year. The high rate of detection of infectious enteroviruses in inlet sewage samples (30.1 %) indicates wide diffusion of these viruses in the populations linked to the collectors. The incomplete removal of infectious viruses following sewage treatment highlights possible risks for public health relate to treated waters discharge into the environment.  相似文献   
95.
In the scope of the development of a microarray PhyloChip for the detection of toxic phytoplankton species, we designed a large series of probes specific against targets in the nuclear large subunit (LSU) rRNA of a range of Pseudo-nitzschia species and spotted these onto the microarray. Hybridisation with rRNA extracted from monoclonal cultures and from plankton samples revealed many cross-reactions. In the present work, we tested the functionality and specificity of 23 of these probes designed against ten of the species, using a dot-blot procedure. In this case, probe specificity is tested against the target region in PCR products of the LSU rRNA gene marker region blotted on nitrocellulose filters. Each filter was incubated with a species-specific oligoprobe. Eleven of the tested probes showed specific responses, identifying seven Pseudo-nitzschia species. The other probes showed non-specific responses or did not respond at all. Results of dot-blot hybridisations are more specific than those obtained with the microarray approach and the possible reasons for this are discussed.  相似文献   
96.
Between April and June of 2012 mantisflies (Plega hagenella) were found to be extensively parasitizing the nests of two groups of managed colonzies of eusocial stingless bees (Melipona subnitida) in the semi-arid region of northeastern Brazil. The mantisfly larvae developed inside closed brood cells of the bee comb, where each mantispid larva fed on the bee larva or pupa present in a single brood cell. Mature mantispid larvae pupated inside silken cocoons spun in place within their hosts' brood cells then emerged as pharate adults inside the bee colony. Pharate adults were never attacked and killed by host colony workers. Instead, colony workers picked up the pharates and removed them from the nest unharmed, treating them similar to the way that the general refuse is removed from the nest. Adult mantispids subsequently eclosed from their pupal exuviae outside the nest. Manipulative experiments showed that post-eclosion adult mantispids placed back within active bee colonies were quickly attacked and killed. These observations demonstrate that pharate and post-eclosion adults of P. hagenella are perceived differently by colony workers and that delayed adult eclosion is an important functional element in the parasitic life strategy of P. hagenella, allowing adults to escape without injury from the bee colonies they parasitize.  相似文献   
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The alternation of glacial and interglacial events during the Pleistocene has produced changes in species distribution ranges leading to bottlenecks and alterations of patterns of gene flow. The European stalked barnacle, Pollicipes pollicipes, is a sessile pedunculate cirripede that inhabits the rocky intertidal frame, from Senegal to the northwestern coast of France. In this work, we have analyzed a fragment of the mitochondrial gene cytochrome c oxidase subunit I for 569 individuals of P. pollicipes in order to investigate whether the shifts in climatic conditions that occurred during the Pleistocene influenced the current pattern of distribution of genetic variation of P. pollicipes. A pre-last glacial maximum pattern of demographic expansion was found, in concordance with many other North Atlantic marine species. On the other hand, three potential glacial refugia were identified: North African coasts, northwestern Iberian Peninsula and English Channel/Brittany.  相似文献   
99.
Feedstock and compost samples were collected from twenty composting plants and analysed from the microbiological point of view. Faecal indicator organisms were determined in order to evaluate the efficacy of processes for the removal of pathogenic micro-organisms with similar survival characteristics and to verify their suitability as appropriate markers of microbial quality of composted products. In addition to the classical bacterial indicators, selected organisms, such as Salmonella, Giardia, Cryptosporidium, Clostridium spores and helminth ova, were investigated. Statistically significant differences in the removal of the different micro-organisms were observed with regard to both the different composting plants (P < 0.05) and feedstock composition (P < 0.05). In fact, compost obtained by feedstock containing sewage sludge was shown to have a better hygienic quality in comparison with compost containing green discards and municipal solid waste as raw matter. Giardia cysts, Cryptosporidium oocysts and helminth ova were not effective indicators of hygienic quality of compost, whereas Clostridium perfringens spores, because of their high resistance to treatments, could be considered as an additional model for assessing the composting process, especially with regard to more resistant pathogen reduction.  相似文献   
100.
The aim of this study was to establish the temporal trends and spatial distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in Ria de Vigo by means of studying the PAH burden in wild mussels. The samples were collected in eight sites along the margins of the Ria de Vigo during November from 1998 to 2008 and Polycyclic Aromatic Hydrocarbon contents were determined using high performance liquid chromatography–fluorescence derivatization (HPLC–FLD). Quality of chemical analysis was guaranteed by participation in QUASIMEME intercalibration exercises carried out during the period of analysis. The concentrations for the sum of 13 PAHs were in the range 24–480 μg/kg dw, typical of an urban and industrialized area (50–500 μg/kg dw) except for a punctual input in La Guía in 1998 that led to a concentration above 1,000 μg/kg dw. In general, the sites in the outermost section of the estuary (ría) showed the lowest values, with an increasing gradient in the medium and inner parts of the ría. Temporal patterns show, in general, a downward trend. The relative proportion of 3 and 4 ring PAHs also varies with the site, the former being predominant in the outermost area and the latter in the medium and inner parts of the ría. This is consistently related with the sources and processes taking place in different areas of the estuary.  相似文献   
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