263 research outputs found
The Evolution of the World Trade and the Italian ‘Anomaly’: A New Look
This work provides an empirical assessment of the âsophisticationâ of the Italian international specialization pattern and of its evolution during the period 1980−2000. In particular we discuss the Italian âanomalyâ, i.e. the evidence that Italy displays a specialization pattern more similar to the one of emerging economies than to the one of countries of comparable level of per-capita income. We show that combining the information coming from a new index measuring the income/productivity content of traded goods, i.e. the PRODY index recently proposed in Hausmann et al. (2005), with the index of Revealed Comparative Advantages (RCA) can shed light on the Italian anomaly. We begin providing a detailed picture of the theoretical and empirical characteristics of the PRODY index. In particular we calculate the index for 1980, 1990 and 2000 mapping its dynamics through that period. Then we describe the characteristic and evolution of the Italian RCA using both parametric and non parametric techniques finding that the Italian pattern of specialization is particularly persistent. Finally, we describe the co-evolution of the PRODY and of the RCA indexes. Our analysis shows that in the last two decades, the world trade has been rapidly changing with Italy becoming increasingly more competitive and specialized in products that are characterized by decreasing income/productivity levels. Thus, while the Italian âanomalyâ was not a problem in the past, it may have become an obstacle to future growth.Specialization pattern, RCA, PRODY index, Italian ’anomaly’
The evolution of world trade and the Italian ‘anomaly': a new look
This work provides an empirical assessment of the 'sophistication' of the Italian international specialization pattern and of its evolution during the period 1980 � 2000. In particular we analyse the well-known Italian trade 'anomaly' combining the information coming from the PRODY index (Hausmann et al. (2005)) with the RCA index. Our results show that in the last two decades, the world trade has been rapidly changing with Italy becoming increasingly more competitive and specialized in products that are characterized by decreasing income/productivity levels. Thus, while the Italian 'anomaly' was not a problem in the past, it may have become an obstacle to future growth.PRODY index,RCA,Specialization pattern
Spatial based approach to fisheries management. An application to bottom trawling in the strait of Sicily
At the beginning of my thesis project, considering that some stocks are in overfishing status due to both high fishing effort and high level of juveniles in the catch, my main purpose was to understand how to contribute to improving the state of the fishery resources of the Mediterranean Sea.
To mitigate the overfishing, the General Fisheries Commission for the Mediterranean (GFCM) adopted several Fishery Restricted Areas, which are geographically defined areas where some specific fishing activities are temporarily or permanently banned or restricted in order to reduce the exploitation patterns and conservation of specific stocks as well as of habitats and deep-sea ecosystems, including the Essential Fish Habitats (EFH) and the Vulnerable Marine Ecosystems (VME).
Considering that GFCM established 3 Fisheries Restricted Areas (FRAs) in the Strait of Sicily (SoS) in 2016 aimed at protecting the nursery areas of the deep-water rose shrimp (DPS, Parapenaeus longirostris – Lucas, 1846) and the European hake (HKE, Merluccius merluccius – Linnaeus, 1758) to reduce the exploitation pattern of undersized species, in my thesis project I devoted myself to evaluate the effect of the FRAs on the status stock and the fishery performance using a spatial bio-economic model
Length-Weight Relationships of 52 Species from the South of Sicily (Central Mediterranean Sea)
The Length-Weight relationships (LWRs) of 52 species (14 never reported before) of fishes, crustaceans and cephalopods living on the shelf and upper slope off Southern Sicily are provided. Data were collected in the framework of the International bottom trawl survey in the Mediterranean (MEDITS) in the South of Sicily (Central Mediterranean), covering a time frame ranging from 2012 to 2019. Linear regressions were significant for all species (p < 0.05) with R-2 values ranging from 0.86 to 0.99. The intercept (a) of LWRs ranged from 0.0003 to 0.4677, while the slope (b) ranged from 2.1281 to 3.306. The Welch t-test, used to evaluate differences between the obtained LWRs with those reported in the literature, revealed that most of the LWRs (about 55%) reported in this study are in disagreement with those obtained previously by other authors from the Strait of Sicily. It is expected that the results obtained from this study will contribute to filling the knowledge gap of fish populations in this area and also assist fisheries scientists in future stock assessment studies
Aerobic Microbial Inactivation Kinetics of Shrimp Using a Fixed Minimal Ozone Discharge: A Fact or Fib During Iced Storage?
AbstractAmong researchers worldwide, the combination of preservation methods aimed to achieve improved effects on microbial inactivation of seafood products is an area of research receiving increasing interest. Globally also, the demand for high quality minimally processed food products are on the increase. Ozone treatment, three decade – long declared 'Generally Recognized As Safe' and approved as food contact sanitizing agent has evolved up to recent times where it assumes the likes of domestic food-processing facilities manufactured with environment-friendly status ensuring consumer safety. On the other hand, the subject of inactivation kinetics of seafood microorganisms following ozone treatment is still under debate. Furthermore, kinetic models remain the economical and quick approach to predict the preservation parameters. Nevertheless, there is paucity of information regards aerobic microbial inactivation of crustacean product arising from fixed minimal ozone discharge. Is the phenomenon of aerobic microbial inactivation kinetics of shrimp product subject to a fixed minimal ozone discharge during iced storage a fact or fib? To answer this, the aerobic microbial inactivation kinetics of shrimp during iced storage of up to 11 days was inspected. The process conditions comprised of a fixed ozone concentration of 100mg/h minimally discharged at wash time of 1min as well as iced storage of up to 11 days. Minimal ozone treatment was applied either prior to or during iced storage situations. Aerobic microbial inactivation presented significant effects during iced storage (P<0.05). Line of fit that could best describe the aerobic microbial inactivation kinetics showed adequacy only at the fourth order of storage time 'x' variable, which could only but account for between 75 - 96% of explained variance. Overall, aerobic microbial inactivation kinetics of shrimp using a fixed minimal ozone discharge appears quantitatively possible even though it decreases as iced storage progresses
Exploring the feasibility of technological transfers of two by-catch reduction devices in the crustacean bottom trawling of the central Mediterranean
Introduction: Most Mediterranean fish stocks are overexploited owing to high
fishing efforts and poor exploitation patterns. Demersal trawl fisheries are
considered the most impactful fishery type because of the high quantities of
unwanted catch that is then routinely discarded at sea.
Methods: In the present study, two types of by-catch reduction devices (BRDs),
that is a sorting grid (Grid-T45 40 mm) and a T90 50 mm codend, were
compared to a typical commercial bottom trawl net (control) in terms of size
structures and catch per unit effort to assess the effect of gear modification on
the selectivity of crustacean fisheries in the central Mediterranean Sea. In
particular, three randomly selected trawlers were involved in a paired hauls
experiment fishing at the same time in the same fishing ground. Each trawler
carried out four hauls per day during a 3-day campaign for a total of 36 hauls. The
target species of the fishery is Parapenaeus longirostris (herein DPS), and the
main commercial by-catch is Merluccius merluccius (herein HKE).
Results: The results showed that the landing per unit effort (LPUE) of DPS was
higher for Grid-T45 40 mm net, although it did not differ significantly from that of
the control net. Conversely, the discard per unit effort (DPUE) of the control net
was significantly higher than of both BRD configurations. For HKE, a slightly
higher LPUE was recorded using the T90 50 mm codend compared to that of the
control, but this result was not statistically significant. The lowest DPUE was
found for the T90 50 mm codend, with significant differences compared to that
of the control and Grid-T45 40 mm net. The catch comparison of the size
structures analysed through generalised linear mixed models highlighted that the
Grid-T45 40 mm net was more effective in catching adult DPS, whereas the T90
50 mm codend was more selective for adult HKE
Discussion: In conclusion, although further studies should be carried out in
future to test the performance of the BRDs in different areas and seasons, the
investigated gear seems to be promising for reducing the catch of undersized
individuals and contributing to mitigating the current overfishing of DPS and HK
Inhalation therapy in the next decade : Determinants of adherence to treatment in asthma and COPD
Peer reviewedPublisher PD
All is fish that comes to the net: metabarcoding for rapid fisheries catch assessment
Monitoring marine resource exploitation is a key activity in fisheries science and biodiversity conservation. Since research surveys are time‐consuming and costly, fishery‐dependent data (i.e. derived directly from fishing vessels) are increasingly credited with a key role in expanding the reach of ocean monitoring. Fishing vessels may be seen as widely ranging data‐collecting platforms, which could act as a fleet of sentinels for monitoring marine life, in particular exploited stocks. Here, we investigate the possibility of assessing catch composition of single hauls carried out by trawlers by applying DNA metabarcoding to the dense water draining from fishing nets just after the end of hauling operations (hereafter ‘slush’). We assess the performance of this approach in portraying β‐diversity and examining the quantitative relationship between species abundances in the catch and DNA amount in the slush (read counts generated by amplicon sequencing). We demonstrate that the assemblages identified using DNA in the slush satisfactorily mirror those returned by visual inspection of net content (about 71% of species and 86% of families of fish) and detect a strong relationship between read counts and species abundances in the catch. We therefore argue that this approach could be upscaled to serve as a powerful source of information on the structure of demersal assemblages and the impact of fisheries
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