36 research outputs found
The Lagoons of Corfu: multiple impacts, conservation strategies and economic exploitations
In the Island of Corfu there are seven lagoons which have different biological and
chemical characteristics and also different impacts and human interventions. In this research, a
preliminary description of the lagoons is reported using available data from the literature.
The lagoons of Corfu have been poorly studied from the point of view of ecological functuins and
biodiversity. Specifically the lagoons are: 1.Lagoon Korission, it is the largest lagoon of Corfu.
Located in the southwest of the island has an area of 600hectares approximately. Works like a fish
farm and is protected area Natura 2000. The main intervention of the lagoon is the increasing of
the human activities in the area of the lagoon; 2. Lagoon Chalkiopoulou, the second largest lagoon
of Corfu, it has a total size of 180 hectares. There was a fish farm fifteen years ago. It is estimated
that the last seventy years the lagoon has lost about 1/3 of its extent. This lagoon has received
the most and the major intervention is the reduction in the area in order to create the Airport of
Corfu; 3.Lagoon Antinioti, it is located northeast of Corfu and it has a total size of 100 hectares
with the marshland Kounoufadi which is part of the lagoon. Works like a fish farm and is included
in the protected areas Natura 2000. The main interference of the area has been done on the part of
the marshland Kounoufadi where twenty years ago have been put polders by the municipality of
Corfu in order to build a Municipal Stadium; 4. Lagoon Alykes Lefkimmis, it is a small lagoon of about 30 hectares in the southeast of Corfu. Along with former Alykes Lefkimmis is included in
the protected areas Natura 2000. There is not significant human intervention in the lagoon
in addition with the former Saline of Lefkimmi (which forms a single ecosystem) for which the
area has decreased due to residential use. Three small lagoons in the area of Erimitis
which is in the northeast part of Corfu, there are 3 small lagoon ecosystems (Akoli, Vromolimni
and Avlaki) located on the northeast coast of Corfu. Each of these has a size of 2-4hectares. The
most remarkable is that the lagoon Akoli in the past served as a fish farm and had an artificial
orifice communicating with the sea. Such abandonment of this orifice it is noticed a decrease in
the depth of the lagoon
Size–Abundance Relationships of Freshwater Macroinvertebrates in Two Contrasting Floodplain Channels of Rhone River
Body size is perhaps the most fundamental property of an organism and its relationship with abundance is one of the most studied relationships in ecology. Although numerous studies have examined these relationships in local communities, few have investigated how they vary at different temporal and spatial scales. We investigated the relationship between body size and abundance of local macroinvertebrate communities in two floodplain channels of the French upper Rhone River. The two channels differ in their vegetation coverage (high vs. low vegetation) and hydrological regimes. The shapes of the size–abundance relationship were similar between channels on a yearly basis but differed when compared between months. The variation in local size–abundance relationships between months was related to variation in the functional diversity across time. Our findings suggest that local size–abundance relationships are able to quantitatively describe temporal changes in community structure, showing the importance of relating diversity with ecosystem function in a more realistic context
Variation of leaf litter decomposition among rivers, lagoons and sea: an experiment from Corfu island (Greece)
In aquatic ecosystems, the decomposition of organic detritus represents one of the most important
ecosystem functions, which support complex detritus-based food webs that determine the critical balance
between carbon mineralization and sequestration. The performance of the decomposition process is usually
expressed as rate of decomposition, being a synthetic measure that take into account both abiotic and biotic
factors. Decomposition rates have been also applied to evaluate the ecological status in terms of ecological
functionality. However, despite a growing number of studies have tested the rate of decomposition between
leaves of different riparian tree species in different aquatic ecosystems including rivers, transitional waters
and sea, no comparative study among ecosystems typology is available up to date. Here, we compare
decomposition rates from rivers, lagoons and sea of Corfu island (Greece). Five sampling sites were fixed in
each of the three of the most important rivers and lagoons; other five sampling sites were fixed in the sea
around the island. Twelve leaf packs containing 3±0.005 g of oven-dried Phragmites australis leaves were
submerged in April 2014 and retrieved in May 2014 (after 30 days). Abiotic parameters were recorded in
both sampling times. The retrieved leaf packs were cleaned and the macroinvertebrates retained were
removed, counted, identified at lower taxonomic level and weighted. Leaf pack decomposition rates were
calculated, and their variability was compared within each aquatic ecosystem, within each ecosystem
typology (river, lagoon, sea) and among ecosystem typology. The results are going to be presented on the
poster
Integrative genomic analyses reveal an androgen-driven somatic alteration landscape in early-onset prostate cancer
Early-onset prostate cancer (EO-PCA) represents the earliest clinical manifestation of prostate cancer. To compare the genomic alteration landscapes of EO-PCA with "classical" (elderly-onset) PCA, we performed deep sequencing-based genomics analyses in 11 tumors diagnosed at young age, and pursued comparative assessments with seven elderly-onset PCA genomes. Remarkable age-related differences in structural rearrangement (SR) formation became evident, suggesting distinct disease pathomechanisms. Whereas EO-PCAs harbored a prevalence of balanced SRs, with a specific abundance of androgen-regulated ETS gene fusions including TMPRSS2:ERG, elderly-onset PCAs displayed primarily non-androgen-associated SRs. Data from a validation cohort of > 10,000 patients showed age-dependent androgen receptor levels and a prevalence of SRs affecting androgen-regulated genes, further substantiating the activity of a characteristic "androgen-type" pathomechanism in EO-PCA
Evaluation of appendicitis risk prediction models in adults with suspected appendicitis
Background
Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis.
Methods
A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis).
Results
Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent).
Conclusion
Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified
Temperature and predator cues interactively affect ontogenetic metabolic scaling of aquatic amphipods: T and P effect on metabolic scaling
A common belief is that body mass scaling of metabolic rate results chiefly from intrinsic body-design constraints. However, several studies have shown that multiple ecological factors affect metabolic scaling. The mechanistic basis of these effects is largely unknown. Here, we explore whether abiotic and biotic environmental factors have interactive effects on metabolic scaling. To address this question, we studied the simultaneous effects of temperature and predator cues on the ontogenetic metabolic scaling of amphipod crustaceans inhabiting two different aquatic ecosystems, a freshwater spring and a saltwater lagoon. We assessed effects of phenotypic plasticity on metabolic scaling by exposing amphipods in the laboratory to water with and without fish cues at multiple temperatures. Temperature interacts significantly with predator cues to affect metabolic scaling. Our results suggest that metabolic scaling is highly malleable in response to short-term acclimation. The interactive effects of temperature and predators show the importance of studying effects of global warming in realistic ecological contexts
Size dependency of patch departure behavior: evidence from granivorous rodents
Individual size is a major determinant of mobile organisms’ ecology and behavior. This study aims to explore whether allometric scaling principles can provide an underlying framework for general patterns of resource patch use. To this end, we used giving-up densities (GUDs), that is, the amount of resources remaining in a patch after a forager has quit feeding, as a comparative measure of the amount of resources exploited by a forager of any given size. We specifically tested the hypothesis that size-dependent responses to both internal (energy requirement) and external (risk management) forces may have an effect on GUDs. We addressed this topic by conducting an extensive meta-analysis of published data on granivorous rodents, including 292 GUD measurements reported in 25 papers. The data set includes data on 22 granivorous rodent species belonging to three taxonomic suborders (Castorimorpha, Myomorpha, and Sciuromorpha) and spans three habitat types (desert, grassland, and forest). The observations refer to both patches subject to predation risk and safe patches. Pooling all data, we observed positive allometric scaling of GUDs with average forager size (scaling exponent = 0.45), which explained 15% of overall variance in individual GUDs. Perceived predation risk during foraging led to an increase in GUDs independently of forager size and taxonomy and of habitat type, which explained an additional 12% of overall GUD variance. The size scaling exponent of GUDs is positive across habitat types and taxonomic suborders of rodents. Some variation was observed, however. The scaling coefficients in grassland and forest habitat types were significantly higher than in the desert habitat type. In addition, Sciuromorpha and Myomorpha exhibited a more pronounced size scaling of GUDs than Castorimorpha. This suggests that different adaptive behaviors may be used in different contexts and/or from different foragers. With body size being a fundamental ecological descriptor, research into size scaling of GUDs may help to place patch-use observations in a broader allometric framework
Cross-community scaling of benthic macroinvertebrate guilds: a functional approach to community organisation in inland waters of Southern Italy
The search for simple and effective descriptors of biological ecosystem components is a major challenge of
monitoring aquatic ecosystem health. There have been discussed the relevance of body-size-related
descriptors of benthic invertebrate guilds in monitoring the health of aquatic ecosystems. The rationale is that
macroinvertebrate body-size relates individual responses to disturbance pressures through individual energetic,
population dynamics and species coexistence responses.
The mechanistic relevance of individual body-size on coexistence relationships still requires field and laboratory
tests and community level scaling-up. The different proposed models of size abundance distributions offer
promising approaches to scale-up and address the overall role of individual body size in community
organisation.
One of the relationships between body-size and abundance in ecology is the cross-community scaling
relationship (CCSR), which use ecological energetics to evaluate the overall body size based responses to
actors affecting energy flow in ecosystems; external perturbations and pollution are main anthropogenic-based
factors acting on energy flow.
Field experiments on freshwater and transitional water benthic macroinvertebrate guilds from perturbed and
unperturbed ecosystems of Southern Italy (Apulia and Sardinia areas) were designed to test: i. the crosscommunity
scaling relationship relevance of body-size-related constraints on the organization of detritus-based
benthic guilds through the relationship between the average size of an individual in an assemblage and the
total community density; ii. the sensibility of statistical CCSR descriptors to perturbed conditions, compared to
unperturbed ones
Petrological modleling of Bulqiza and Shebeniku ultrabasic massifs with metallogenic implications
65-72 p. Supported by CNRConsiglio Nazionale delle Ricerche (CNR). Biblioteca Centrale / CNR - Consiglio Nazionale delle RichercheSIGLEITItal