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1.
Mar Pollut Bull ; 150: 110768, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31780088

RESUMEN

Macrozoobenthic fouling assemblages were studied in the port area of Livorno, focusing on the occurrence of non-indigenous species (NIS). Sampling was carried out at ten sites characterised by different anthropic impacts related to their use destination. Among the 262 species identified, twenty-six were alien or cryptogenic, seventeen of which were new records for the study area, confirming the role of the port of Livorno as a hotspot of NIS introduction. Multivariate analyses highlighted a strong influence of the use destination on the diversity of macrozoobenthic communities. Even though the majority of transoceanic maritime traffic from and to Livorno pertains to the commercial harbour, the touristic harbour hosted the highest number of NIS, possibly because of secondary spread from other Mediterranean ports. The ALien Biotic IndEX (ALEX) identified all sites as high or good environmental status, but the large number of NIS detected suggests caution about their impact and further spread.


Asunto(s)
Especies Introducidas , Invertebrados , Animales , Organismos Acuáticos , Mar Mediterráneo
2.
J Fish Biol ; 82(3): 856-76, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23464548

RESUMEN

This study provides data on the genetic structuring of the pipefish Syngnathus abaster in the western Mediterranean and Adriatic Seas. A total of 109 specimens were collected in brackish-water biotopes. The control region and three other regions of the mitochondrial genome were analysed. The most relevant result was the high genetic structuring found by Bayesian inference (BI), maximum likelihood (ML) and network analyses, which were consistent in showing three well-separated clusters of S. abaster populations. Furthermore, BI and ML did not support the monophyly of the taxon S. abaster. These results suggest the occurrence of a species complex in the study area, whose differentiation may have occurred since the Pleistocene. The results also show a very high genetic variability at the inter-population level, with no shared haplotypes among sites. Evolutionary forces due to the fragmented nature of the brackish-water habitats may account for the high genetic divergence found among the groups and populations. Finally, although dispersal by rafting over long distances may occasionally occur, this study suggests linear stepping-stone model of colonization to be most likely. The complexity of the results obtained suggests that further studies are needed to elucidate the phylogeny of S. abaster.


Asunto(s)
ADN Mitocondrial/genética , Evolución Molecular , Variación Genética , Filogenia , Smegmamorpha/genética , Animales , Teorema de Bayes , Haplotipos , Funciones de Verosimilitud , Mar Mediterráneo , Análisis de Secuencia de ADN
4.
Mar Environ Res ; 67(4-5): 219-29, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19329181

RESUMEN

The effects of taxonomic resolution on the variance estimates of macrobenthic assemblages were studied at four spatial scales in a Mediterranean coastal lagoon. The assemblages exhibited significant differences at all the investigated scales; however, spatial variability was mainly associated with the smallest and the largest scales. The decrease of taxonomic resolution (from species to family) was not related to a decrease of the overall variability and similar estimates of variance components were obtained using species and family resolution levels. The ordination models derived from species and family abundances were very similar both in terms of location and dispersion effect, while further aggregation to the class level began to alter the observed spatial patterns. In future studies aimed at assessing changes in the lagoon, resources derived from the cost reductions achieved using family level could be employed to plan more frequent surveys and/or to adopt complex spatial sampling designs with a high number of replicates.


Asunto(s)
Ecosistema , Animales , Biodiversidad , Invertebrados/fisiología , Mar Mediterráneo , Análisis Multivariante , Densidad de Población
5.
Mar Pollut Bull ; 58(4): 478-86, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19162282

RESUMEN

We investigated the applicability of the Pearson-Rosenberg (P-R) conceptual model describing a generalized pattern of response of benthic communities in relation to organic enrichment to Mediterranean Sea coastal lagoons. Consistent with P-R model predictions, benthic diversity and abundance showed two different peaks at low (>2.5-5 mg g(-1)) and high (>25-30 mg g(-1)) total organic carbon (TOC) ranges, respectively. We identified TOC thresholds indicating that risks of reduced benthic diversity should be relatively low at TOC valuesabout 28 mg g(-1), and intermediate at values in-between. Predictive ability within these ranges was high based on results of re-sampling simulation. While not a direct measure of causality, it is anticipated that these TOC thresholds should serve as a general screening-level indicator for evaluating the likelihood of reduced sediment quality and associated bioeffects in such eutrophic systems of the Mediterranean Sea.


Asunto(s)
Carbono/análisis , Invertebrados/fisiología , Animales , Biodiversidad , Carbono/metabolismo , Sedimentos Geológicos/química , Mar Mediterráneo , Densidad de Población
6.
Genetica ; 136(1): 1-4, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19002592

RESUMEN

In this paper we addressed the phylogeographical genetic structure of the economically important red shrimp, Aristeus antennatus (Crustacea, Aristeidae) in the Western Mediterranean. Partial mitochondrial regions of the cytochrome c oxidase subunit I (514 bp) and ribosomal 16S subunit (547 bp) were sequenced in 137 individuals collected at three localities: Catalan Sea, Ligurian Sea and the southern Tyrrhenian Sea. Values of haplotypic diversity were h = 0.552-0.724, whereas those for nucleotide diversity were pi = 0.0012-0.0026. Among-sample genetic diversity was not significant and no geographical patterns in the distribution of haplotypes were apparent. Results of the present study are consistent with a past population expansion that occurred <2,000 years ago. Despite the current fishing pressure, genetic variability appears to be sufficiently high to keep A. antennatus populations stable over time. Dispersal-related life history traits may account for the shallow genetic structure. Our results are not in contrast with the hypothesis of sustainability of Western Mediterranean red shrimp fisheries predicted on the basis of previously obtained biological results.


Asunto(s)
ADN Mitocondrial/química , Penaeidae/genética , Animales , Estructuras Genéticas , Variación Genética , Geografía , Haplotipos , Región Mediterránea
9.
Pediatr Med Chir ; 6(6): 785-9, 1984.
Artículo en Italiano | MEDLINE | ID: mdl-6545591

RESUMEN

Between the years 1981 and 1983 we treated with Ceftriaxone (Cx) 34 children--aged 15 days to 13 years--affected with serious infections: 18 infections of lower respiratory tract, 1 sepsis caused by E. Coli, 1 meningitis with cloudy cerebrospinal fluid, 1 submandibular adenitis with otitis, 1 otitis, 12 infections of the urinary tract caused by Proteus mirabilis, E. Coli, Klebsiella oxitocica and Klebsiella pneumoniae. Whenever bacteria were isolated by cultures, sensibility in vitro to Cx was tested. Cx was given i.m. or i.v. at a dose ranging from 50 to 135 mg/Kg/die according to the age and the seriousness of the infections; in 17 children Cx was administered once daily, in the other patients in two divided doses. The following laboratory measurements were obtained before, during and after treatment: complete blood cell count, platelet count, total bilirubin, creatinine, SGOT, SGPT, alkaline phosphatase and urinalysis. Patients were also monitored daily for clinical signs and symptoms such as fever, general conditions, heart rate, respiratory rate, blood pressure. Twenty children showed a good clinical response (1 sepsis, 1 otitis, 1 adenitis, 1 meningitis, 12 infections of the urinary tract, 4 infections of the lower respiratory tract); urine sterilization was achieved after three days of therapy in all patients with infections of the urinary tract. Remarkable clinical and radiological improvement in 9 patients with infections of lower respiratory tract was observed while in only 4 children with bronchopneumonia therapy was ineffective although the dosage of Cx was adeguate; in these patients a further antibiotic treatment was necessary for a complete recovery.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Ceftriaxona/uso terapéutico , Neumonía/tratamiento farmacológico , Infecciones Urinarias/tratamiento farmacológico , Adolescente , Ceftriaxona/efectos adversos , Niño , Preescolar , Evaluación de Medicamentos , Femenino , Humanos , Lactante , Recién Nacido , Masculino
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