Comparison between Artisanal Fishery and Manila Clam Harvesting in the Venice Lagoon by Using Ecosystem Indicators: An Ecological Economics Perspective

Artisanal fishery in the Venice lagoon is a multi-target activity with a long tradition. It was the main fishing activity till the late ’80s when, after the introduction and spread of the Manila clam (Tapes philippinarum), the mechanical clam harvesting started. A mass-balance model of the lagoon ecosystem was developed using the Ecopath with Ecosim software. 73 scenarios, obtained by changing the fishing effort of the two different types of fishery, were used to explore their impact on the ecosystem. A set of indicators was applied in order to compare the two fishing activities. The results obtained showed that the two activities are strongly interlinked, even through they don’t exploit the same resources. The mechanical clam harvesting could reasonably be considered to be the driving force; it is capable of determining the state of lagoon ecosystem. The above mentioned factors create a lot of conflict between the two types of fishery.Artisanal fishery, Indicators, Dynamic model, Venice Lagoon, Fishing impact, Social and economic value

Comparison between Artisanal Fishery and Manila Clam Harvesting in the Venice Lagoon by Using Ecosystem Indicators: An Ecological Economics Perspective

Artisanal fishery in the Venice lagoon is a multi-target activity with a long tradition. It was the main fishing activity till the late '80s when, after the introduction and spread of the Manila clam (Tapes philippinarum), the mechanical clam harvesting started. A mass-balance model of the lagoon ecosystem was developed using the Ecopath with Ecosim software. 73 scenarios, obtained by changing the fishing effort of the two different types of fishery, were used to explore their impact on the ecosystem. A set of indicators was applied in order to compare the two fishing activities. The results obtained showed that the two activities are strongly interlinked, even through they don't exploit the same resources. The mechanical clam harvesting could reasonably be considered to be the driving force; it is capable of determining the state of lagoon ecosystem. The above mentioned factors create a lot of conflict between the two types of fishery

Tra biologia e cultura. Otto disegni per Remo

Drawing has been associated with man's cultural history since its very beginning, when the need to express oneself arose. With the passing of time, it has gained autonomy and lost the function of support and integration to written and oral verbal communication. This writing is about the 'accessory' function of drawing, with some examples taken from a recent dialogue between Remo Ceserani and the author. Finally, it is remarked the phylogenetic relationship between drawing and writing, which involves, in different species, both the biologic and the cultural evolution.Il disegno ha accompagnato la storia culturale dell’uomo fin dagli inizi quando è nata la necessità di esprimersi. Col tempo ha assunto un’autonomia espressiva, perdendo quella funzione di supporto e integrazione alla comunicazione verbale, sia essa scritta che orale. E’ appunto di questa funzione accessoria che si discute in questo scritto, offrendo alcuni esempi estratti da un lungo dialogo che recentemente ha avuto luogo tra Remo Ceserani e l’autore. Infine si rimarca la parentela di carattere filogenetico che lega il disegno alla scrittura e che coinvolge, in differenti specie, sia l’evoluzione biologica che quella culturale

Reprogramming energy homeostasis in children with overweight through cognitive training and social interaction. A study protocol to estimate leptin sensitivity

Leptin is a hormone secreted by adipocytes in proportion to the size of adipose tissue. By acting on its receptor, LepRb, primarily expressed in the hypothalamus, leptin promotes a negative energy balance by strongly suppressing appetite and stimulating energy expenditure. The majority of patients with obesity exhibit elevated leptin production, indicating that leptin becomes ineffective in regulating energy balance in this context. In the growing child, leptin modulates synaptic plasticity and thus leptin resistance may exert a key role in neurodevelopment. So far, studies in humans have investigated leptin secretion but not leptin resistance. We designed a research protocol (RESILIENT project) to study leptin sensitivity in vivo and ex vivo in growing children (6 to 11 years of age), and its association with neurodevelopmental features. The project will investigate the additive effects of Cognitive Training (CT) and Social Training (ST) on leptin sensitivity, compared to stand-alone Intensive Health Behaviour Treatment (IHBT) in children with obesity or overweight. In vivo investigation of leptin sensitivity may be particularly important for providing evidence of the metabolic and cognitive effects necessary for developing novel anti-obesity treatments.Clinical trial registrationhttps://clinicaltrials.gov/study/, identifier NCT06931730

The nest-holding grass goby (Zosterisessor ophiocephalus) male adjusts the spawning activity in relation to parasitic nest intrusions.

This study examines the temporal pattern of spawning behavior by the territorial (i.e. nest-holding) grass goby male, Zosterisessor ophiocephalus, in response to sneak intrusions by the small parasitic male under controlled laboratory conditions. The spawning activity of the territorial male consists of a sequence of upside-down movements on the ceiling of the nest accompanied by undulations of the body and sperm release. Five pairs of one territorial male and one parasitic male, each kept inside a large tank provided with an artificial buried nest (always occupied by the territorial male) and one small tunnel-shaped shelter (always occupied by the small male), were observed during one-female spawning taking place in the innermost part of the nest (i.e. the nest chamber). During the spawning, the presence of the small male nearby the nest openings elicited aggressive behavior and increased nest patrolling by the territorial male. In one spawn the small male never attempted to enter the nest. In four spawns the small male entered one to three times the nest chamber (sneaks), staying there from 2 to 203 s until the large male chased him away. The temporal patterning of the spawning activity by the territorial male (bouts of upside-down, U-D), and its changes following a sneak by the small male, were investigated using bout analysis and correlative tests. Results showed the length of bouts U-D did not change significantly after a sneak intrusion. whereas gap length (i.e. the period between subsequent bouts U-D) decreased significantly after each sneak intrusion. The mean duty cycle of bouts U-D tended to be positively correlated to the number of sneaker intrusions of each replicate. Results are discussed in the light of current knowledge on sperm competition among externally fertilizing teleosts

Ecological stages of the Venice Lagoon analysed using landing time series data

The time series of landings in the Venice Lagoon from 1945 to 2001 were analysed with the aim of explaining the ecosystem changes occurred. The comparative analysis of the total landings and mean Trophic Level (mTL) time series allowed to identify four different stages in the lagoon ecosystem. The first period, from 1945 to 1973, was characterised by increasing trends in the landings and their mTL. The second one, from 1974 to 1989, showed a decrease in the landings but still an increase in the mTL. The third period, from 1990 to 1998, had again a positive trend in the landings, but the mTL showed a sharp decline. After 1998, a slight decreasing trend in both mTL and landings was observed: the analyses of the artisanal fishery landings only date back to 1995 this effect. The presence of four distinct periods was also confirmed by the analysis of the trends of other indices estimated using landings data: the Fishing in Balance index (FiB), the Trophic Efficiency (TE) and the Pelagic on Demersal landings ratio (P/D). In the first period, the increasing fishing pressure, along with no evidence of ecosystemcrisis, suggested that an increased nutrient dischargewas supporting it; analogously, the bottom-up effects had driven the dynamics of the ecosystem also in the second period, when the decrease in nutrient loads caused a shift of the primary producers fromplanktonic tomacrobenthic. The spreading of theManila clam, a non-native species, and the development of its massive mechanical exploitation have been the main forces driving the ecosystem during the third period, forwhich, however, no signs of criseswere detected. The fourth period showed evidence of the ‘‘fishing down the food web’’ effect. Possible causes of such an effect were investigated and allowed us to conclude that not overfishing, but the effects ofmechanical harvesting of theManila clamhad caused relevant impacts on habitat and benthic communities, concluding that the present level of exploitation of the stock ofManila clamis not sustainable in the long term. Our findings were also compared with the general evolution of enclosed seas, subjected to high nutrient loads, fishing pressure and invasion by non-native species

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come