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1.
Sci Rep ; 12(1): 14905, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050357

RESUMEN

In the Mediterranean Sea, the Strait of Messina (MS) is a very peculiar area, connecting highly different regions and representing a privileged observatory for an early comprehension and assessment of ecosystems shifts. It is hypothesized that the outbreaks observed near the coast of many sites in the Mediterranean Sea may be the result of transport of permanent populations of P. noctiluca in pelagic waters to the coast, caused by specific hydrodynamic conditions. By both visual observations and numerical experiments our objective is twofold: (A) to help clarify whether the basin of the Aeolian Islands Archipelago (AIA), in the Southern Tyrrhenian Sea (STS), may be the site from which large populations of P. noctiluca are transported to the MS, and (B) to evaluate whether the upwelling turbulent system of the MS can be an energetic opportunity for this species. It should offer a rich habitat without jeopardizing the overall survival of the population, that is subject to stranding due to strong currents. Although very different, the two involved ecosystems (AIA and MS ) are complementary for the success of Pelagia noctiluca life cycle. Outputs obtained by coupling the 3D hydrodynamic model (SHYFEM) with a Lagrangian particle tracking model support the hypothesis of a connectivity between these two ecosystems, particularly in the first half of the year, indicating the coastal areas around the AIA as potential optimal source location for Pelagia larval stages. We support the very attractive hypothesis that two connected systems exist, the former one favours Pelagia's reproduction and acts as a nursery and the latter favours its growth due to higher productivity. We speculate that the reproductive population of the AIA is not permanent, but is renewed every year by individuals who have fed and quickly grown in the MS and who are passively transported by downwelling along canyon "corridors".


Asunto(s)
Dinoflagelados , Escifozoos , Animales , Ecosistema , Humanos , Mar Mediterráneo
2.
Balkan J Med Genet ; 23(2): 87-92, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33816077

RESUMEN

Activating disease-causing variants in the thyrotropin-receptor (TSHR) gene are associated with familial or sporadic congenital non-autoimmune hyperthyroidism. Familial non-autoimmune hyperthyroidism (FNAH) is a rare form of hyperthyroidism with 41 families reported so far in the TSHR gene mutation database. We present clinical and genetic features of 11 patients with FNAH across four generations of a Slovenian family. They all developed clinical features of hyperthyroidism but did not show characteristics of autoimmune hyperthyroidism. Members of the initially diagnosed generation were diagnosed as hyperthyrotic after they developed cardiac complications (rhythm disorders, thromboembolic events, cardiac insufficiency), while patients in the younger generations were diagnosed earlier, and consequently, early cardiovascular complications were less frequent. All patients had a novel heterozygous TSHR variant NP_ 000360.2: p.Met453Val (NM_000369.2: c.1357A>G) predicted to be pathogenic. Therefore, besides expending the mutational spectrum of the activating TSHR variants in FNAH, our experience with this multi-generation family confirms the need for early diagnosis and appropriate treatment of FNAH.

3.
Mar Environ Res ; 152: 104791, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31640887

RESUMEN

Harmful invader ctenophore Mnemiopsis leidyi's expansions in the Eurasian Seas, its spatio-temporal population dynamics depending on environmental conditions in recipient habitats have been synthesized. M. leidyi found suitable temperature, salinity and productivity conditions in the temperate and subtropical environments of the semi-enclosed seas, in the coastal areas of open basins and in closed water bodies, where it created autonomous populations. M. leidyi changes its phenology depending on seasonal temperature regime in different environments. We assessed ranges of sea surface temperature, sea surface salinity and sea surface chlorophyll values, sufficient for M. leidyi general occurrence and reproduction based on comprehensive long-term datasets, contributed by co-authors. This assessment revealed that there are at least two eco-types (Southern and Northern) in the recipient seas of Eurasia with features specific for their donor areas. The range of thresholds for M. leidyi establishment, occurrence and life cycle in both eco-types depends on variability of environmental parameters in their native habitats.


Asunto(s)
Ctenóforos , Especies Introducidas , Animales , Océanos y Mares , Dinámica Poblacional , Reproducción , Salinidad
4.
Mar Pollut Bull ; 58(8): 1178-1186, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19394971

RESUMEN

The present study aimed to establish potential indicators of fish farming pollution in muddy substrate, by means of meiofauna, and to test whether the effect of the fish farm is more important to determine the meiofauna community than the seasonal environmental conditions. Sampling was performed in spring, after several months of light feeding, and in summer, at high food supply. Samples were collected in three directions at various distances from the floating cages. Harpacticoid copepods and kinorhynchs, whose abundance decreased under the cages, were put forward as indicator taxa. However, harpacticoid copepods were sensitive to fish farm only, while kinorhynchs showed responsiveness to fish farm and to seasonal environmental conditions. Total meiofauna density was dependent on season sensu stricto. The nMDS clearly showed a 'cage community' and 'control community' in both sampling occasions; therefore it is a good tool for impact assessment.


Asunto(s)
Biodiversidad , Explotaciones Pesqueras , Estaciones del Año , Animales , Clorofila , Densidad de Población , Salinidad , Agua de Mar/química
5.
Water Sci Technol ; 46(8): 19-28, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12420962

RESUMEN

The present paper is an attempt to test the applicability of the trophic state index (TRIX) for scaling the eutrophication along the Bulgarian Black Sea coastal zone in concert with a number of chemical and biological descriptors aimed at selection of relevant indicators of marine coastal area ecological quality. The following environmental parameters have been considered: t(o), salinity, nutrients--inorganic P, N and dissolved Si, dissolved oxygen and oxygen saturation, phytoplankton--taxonomic structure, abundance and biomass, chlorophyll a, zooplankton--taxonomic structure, abundance and biomass. Principal Component Analysis was applied in order to figure out and score the most relevant combination of parameters to discriminate between sites and select representative descriptors (pressure/state) of eutrophication. The following variables are defined as relevant descriptors for classification of the sites: nutrients (N, P, Si) and their molar ratios (N:P and Si:P), the capacity of the system to produce and sustain organic matter (chlorophyll a, phytoplankton biomass), phytoplankton taxonomic dominance (Bacilariophyceae:Dinophyceae biomass ratio), grazing pressure (phytoplankton:zooplankton biomass, Bacilariophyceae:Copepoda), plankton diversity index (Hb and Ha) and the trophic state index (TRIX). The investigated sites under a different anthropogenic impact are classified according to selected descriptors and their water quality state.


Asunto(s)
Monitoreo del Ambiente , Eutrofización , Modelos Teóricos , Animales , Biomasa , Bulgaria , Clasificación , Cadena Alimentaria , Fitoplancton , Dinámica Poblacional , Contaminantes del Agua/análisis , Zooplancton
6.
Ann Ist Super Sanita ; 35(3): 373-81, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10721201

RESUMEN

In the summers of 1988, 1989, and 1991 large quantities of sticky mucilaginous masses occurred in the Adriatic Sea, particularly in its northern part. The mucilage phenomenon has been studied by scientists during past events, but the previous scientific reports back to the thirties of this century. Great efforts have been made since 1988 to understand the nature of the phenomenon. Although remarkable scientific results have been achieved, many questions related to such a complex phenomenon have remained open. In this paper results and hypotheses related to the chemical and biological composition, causes, triggering mechanisms, and responsible organisms for the mucilage phenomenon are briefly reviewed. Finally, some suggestions for future researches are proposed.


Asunto(s)
Geles/análisis , Agua de Mar/análisis , Coloides , Ecosistema , Conceptos Meteorológicos , Océanos y Mares , Fitoplancton , Microbiología del Agua
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