Search results for " mollusk"
showing 9 items of 9 documents
Drivers of shell growth of the bivalve, Callista chione (L. 1758) - Combined it environmental and biological factors
2018
WOS:000426027100014; Seasonal shell growth patterns were analyzed using the stable oxygen and carbon isotope values of live-collected specimens of the bivalve Callista chione from two sites in the Adriatic Sea (Pag and Cetina, Croatia). Micromilling was performed on the shell surface of three shells per site and shell oxygen isotopes of the powder samples were measured. The timing and rate of seasonal shell growth was determined by aligning the delta O-18(shell)-derived temperatures so that the best fit was achieved with the instrumental temperature curve. According to the data, shells grew only at very low rates or not at all during the winter months, i.e., between January and March. Shell…
Mollusk antimicrobial peptides A review from activity-based evidences to computer-assisted sequences
2011
Antimicrobial peptides (AMPs) represent the most universal immune effectors. Molluscs constitute the second largest animal phylum, after Arthropods, in term of number of species. Only a negligible number has been investigated regarding AMPs. The choice of the species to be studied relied on their economical importance and availability. First studies on molluscan AMPs dated from 1996 and were based on biological activities of biochemical-purified fractions. Such approach released all the original structures we know, with biological activity sometimes different from one isoform to another. Then, molecular biology techniques were applied to molluscan AMPs starting in 1999. Complete screening o…
Positive selection in development and growth rate regulation genes involved in species divergence of the genus Radix
2015
AbstractBackgroundLife history traits like developmental time, age and size at maturity are directly related to fitness in all organisms and play a major role in adaptive evolution and speciation processes. Comparative genomic or transcriptomic approaches to identify positively selected genes involved in species divergence can help to generate hypotheses on the driving forces behind speciation. Here we use a bottom-up approach to investigate this hypothesis by comparative analysis of orthologous transcripts of four closely related EuropeanRadixspecies.ResultsSnails of the genusRadixoccupy species specific distribution ranges with distinct climatic niches, indicating a potential for natural …
The carrying capacity for Mediterranean bivalve suspension feeders: evidence from analysis of food availability and hydrodynamics and their integrati…
2004
Abstract In order to assess the carrying capacity of two Mediterranean areas, the Incze et al. model and its modification were applied. Our measures were carried out in the Gulf of Gaeta (Central MED), where mussels ( Mytilus galloprovincialis ) are intensively cultivated (production of approximately 200 t per year) and the Gulf of Castellammare (Southern MED), where bivalve culture is not widely practised. Velocities of water current and in field filtration rates were measured in each area. Total suspended matter (TSM), suspended chlorophyll-a (CHLa), lipid, protein and carbohydrate concentrations in the particulate were measured seasonally and used as tools to evaluate the trophic status …
Characterization of the 3D information of Calyptogena shells
2003
We propose in this paper an application of multiresolution analysis techniques to extract information contained in the growth increments of a bivalve mollusk called: Calyptogena . The first stage consists in extracting a range image of the mollusk’s shell using a 3-D scanner. Applying a multiresolution analysis enables us to localize precisely those growth increments by preserving relevant details. Moreover, interesting spatial and frequency properties of the multiresolution analysis underline information contained on the shell. Intra-individual variation and inter-individual variations are compared to assume some conclusions as for the ontogenetic evolution of the animal such as periodicit…
Qanat, gebbie and water sources: the last refuge for the malacologican freshwater fauna in Palermo (Sicily, Italy)
2017
The surroundings of Palermo were characterized, over the centuries, by the presence of many natural environments of great ecological and faunal importance. These environments were placed in a context characterized by minimal and sustainable urban development and large agriculture areas, dedicated to the development of tree crops such as citrus and orchards. These crops were supported by an imposing irrigation system that, using natural resources such as watercourses, wells and springs, collected and distributed water in soils through tanks, gebbie, qanat, irrigation channels (saje), etc. Fresh water mollusks, like many other animal and vegetable organisms, spread from the natural freshwater…
Toll signal transduction pathway in bivalves: Complete cds of intermediate elements and related gene transcription levels in hemocytes of immune stim…
2014
Based on protein domain structure and organization deduced from mRNA contigs, 15 transcripts of the Toll signaling pathway have been identified in the bivalve, Mytilus galloprovincialis. Identical searches performed on publicly available Mytilus edulis ESTs revealed 11 transcripts, whereas searches performed in genomic and new transcriptome sequences of the Pacific oyster, Crassostrea gigas, identified 21 Toll-related transcripts. The remarkable molecular diversity of TRAF and IKK coding sequences of C. gigas, suggests that the sequence data inferred from Mytilus cDNAs may not be exhaustive. Most of the Toll pathway genes were constitutively and ubiquitously expressed in M. galloprovinciali…
Climate signatures on decadal to interdecadal time scales as obtained from mollusk shells (Arctica islandica) from Iceland
2013
Abstract Pronounced decadal climate oscillations are detected in a multi-centennial record based on shell growth rates of the marine bivalve mollusk, Arctica islandica, from Iceland. The corresponding analysis of patterns in sea level pressure and temperature exhibit large-scale teleconnections with North Atlantic climate quantities. We find that the record projects onto blocking situations in the northern North Atlantic. The associated circulation shows a low-pressure signature over Greenland and the Labrador Sea and a high-pressure system over Western Europe associated with northeasterly flow towards Iceland and weakening in the westerly zonal flow over Europe. It can be speculated that s…