A comparison of node vaccination strategies to halt SIR epidemic spreading in real-world complex networks.

We compared seven node vaccination strategies in twelve real-world complex networks. The node vaccination strategies are modeled as node removal on networks. We performed node vaccination strategies both removing nodes according to the initial network structure, i.e., non-adaptive approach, and performing partial node rank recalculation after node removal, i.e., semi-adaptive approach. To quantify the efficacy of each vaccination strategy, we used three epidemic spread indicators: the size of the largest connected component, the total number of infected at the end of the epidemic, and the maximum number of simultaneously infected individuals. We show that the best vaccination strategies in the non-adaptive and semi-adaptive approaches are different and that the best strategy also depends on the number of available vaccines. Furthermore, a partial recalculation of the node centrality increases the efficacy of the vaccination strategies by up to 80%.

Myiasis by Megaselia scalaris (Diptera: Phoridae) in a python affected by pulmonitis.

Myiases are caused by the presence of maggots in vertebrate tissues and organs. Myiases have been studied widely in humans, farm animals, and pets, whereas reports of myiasis in reptiles are scarce. We describe a case of myiasis caused by the Megaselia scalaris (Loew) in an Indian python (Python molurus bivittatus, Kuhl) (Ophida: Boidae). The python, 15 yr old, born and reared in a terrarium in the mainland of Venice (Italy), was affected by diffuse, purulent pneumonia caused by Burkholderia cepacia. The severe infestation of maggots found in the lungs during an autopsy indicated at a myiasis.

Enzymatic activities and prokaryotic abundance in relation to organic matter along a West-East Mediterranean transect (TRANSMED cruise).

The distribution of extracellular enzymatic activities (EEA) [leucine aminopeptidase (LAP), ß-glucosidase (GLU), alkaline phosphatase (AP)], as well as that of prokaryotic abundance (PA) and biomass (PB), dissolved organic carbon (DOC), particulate organic carbon and particulate total nitrogen (POC, PTN), was determined in the epi-, meso-, and bathypelagic waters of the Mediterranean Sea along a West-East transect and at one Atlantic station located outside the Strait of Gibraltar. This study represents a synoptical evaluation of the microbial metabolism during early summer. Decreasing trends with depth were observed for most of the parameters (PA, PB, AP, DOC, POC, PTN). Significant differences between the western and eastern basins of the Mediterranean Sea were found, displaying higher rates of LAP and GLU and lower C/N ratios more in the eastern than in the western areas. Conversely, in the epipelagic layer, PA and PB were found to be higher in the western than in the eastern basins. PB was significantly related to DOC concentration (all data, n = 145, r = 0.53, P < 0.01), while significant correlations of EEA with POC and PTN were found in the epipelagic layer, indicating an active response of microbial metabolism to organic substrates. Specific enzyme activities normalized to cell abundance pointed out high values of LAP and GLU in the bathypelagic layer, especially in the eastern basin, while cell-specific AP was high in the epi- and bathypelagic zone of the eastern basin indicating a rapid regeneration of inorganic P for both prokaryotes and phytoplankton needs. Low activity and abundance characterized the Atlantic station, while opposite trends of these parameters were observed along the Mediterranean transect, showing the uncoupling between abundance and activity data. In the east Mediterranean Sea, decomposition processes increased probably in response to mesoscale structures which lead to organic matter downwelling.

Records of Chrysomya albiceps in Northern Italy: an ecological and forensic perspective.

Knowledge of the carrion-breeding insects present at a local level is important and necessary for defining the post-mortem interval. Climate changes and globalisation are affecting species ranges and population dynamics. In this note, we report the incidence of Chrysomya albiceps (Diptera: Calliphoridae) on dead human bodies and carrion in Northern Italy. These data confirm the spread of this species in the Northern regions. The partial sequencing of a 583-bp region of the cytochrome oxidase subunit 1 gene of an Adriatic population did not reveal any difference compared to the same genomic region in the African and South American populations of this species.

Use of Lucilia species for forensic investigations in Southern Europe.

The aim of this study was to highlight the importance of evaluating entomological evidence in forensic investigations on a regional scale. To evaluate climatic, geographical and environmental influences on the selection of carrion-breeding fauna in Northern Italy and consequently on inferred forensic data (post-mortem intervals and post-mortem transfer), we present details of six indoor-outdoor cases. Results show that the most abundant species was Lucilia sericata, together with other fly species of entomo-forensic interest, belonging to the Calliphoridae and Sarcophagidae families. In particular, for the first time in Italy, we report finding Phormia regina, Lucilia ampullacea, Lucilia caesar and Sarcophaga (Pandelleana) protuberans on fresh cadavers. The active period of L. sericata in Northern Italy, according to previous findings in Southern Europe, revealing clearcut differences with phenologies in Northern Europe, has important consequences in estimating the period (season, months) of death in cases of long post-mortem intervals (several months or years) if empty puparia of this fly are found. According to our results, the distribution of L. sericata in areas with urban sprawl, like Northern Italian regions, cannot be used to evaluate post-mortem transfer from an urban area to a rural one.

[Forensic entomology and globalisation]. / L'Entomologia forense e la globalizzazione.

The main aim of Forensic Entomology has always been, and is today, to establish the time of death (P.M.I.: Postmortem Period) or, more exactly, how long a carrion has been exposed in the environment. Most of the invertebrate fauna occurring on corpses consists of insects (mostly Diptera and Coleoptera). They are selectively attracted by the decomposing status of the carrion, and form complex communities or biocenosis within necrophagous or sarcophagous species and their predators, parasites and parasitoids, competing each one another. The rapid and continuos changes of the micro-ecosystem (the body), until its breakdown, does not permit the achievement of a steady state or an equilibrium in the animal communities. These continuous modifications give us the possibility to estimate when (and where) the death has occurred, by the identification of the species feeding on the corpse, the knowledge of their life history, and the length of each stage of their cycle at varying the temperature and the other abiotic factors, external to the carrion ecosystem. The P.M.I. today is still largely based on the tables of faunal succession on human cadavers recognised by Mégin in 1894, with few changes proposed by Authors from other countries. In the last years, however, it happens more and more often, that the natural communities are subverted by the presence of allocton species, which can compete, predate or parasite the most common local sarcophagous insects, modifying, this way, the succession waves and the trophic nets. The immission in the environment of foreign species may be voluntary or casual, but in any case is due to anthropic activities. The voluntary immission happens when some species, employed in the biological struggle against pest or dangerous insects, for pollination of allocton plants, or for other commercial utilities, are beyond man's control and swarm onto the environment; the casual spread is due to the globalisation phenomenon, that distributes the "little organisms" by chance, together with travellers, goods and food items. Together with human migratory flows, raw materials and vegetal foodstuffs travelling from Tropical developing Countries to the North of the world, also many tropical and subtropical insects can be carried out from their original lands. Eurioecious and polyphagous species, and species that evolved mechanisms (as diapausa or hibernation) to get over critical environmental conditions have the highest probability of survival. Saprophagous insects, and flies in particular, evolved such capabilities. The mortality of foreign species due to the difference of temperature and seasonally between tropical and temperate areas was, in the past, the most effective factor limiting the geographic propagation of insects. The ongoing global climate changes induce insect populations, now confined to the tropics, to most likely spread towards middle latitudes, where their specific competitors, predators and parasites, which regulate the population growth, are often absent. The lack of a biological control, the warming up of atmosphere temperature and the fall of the differences among seasons induce a more rapid development and an increased number of generations in new species, that often displace the autocton ones. This phenomenon is much more clear in little and simple ecosystems (such as carrion), mostly occur than in large and complex ecosystems, where many more components, vegetal organisms and phytophagous animals included, are present. To demonstrate how globalisation and climate changes are breaking the geographic barriers, we present some cases in which, during our entomoforensic investigations, performed mainly in North-eastern Italy, Neotropical, African and Asiatic necrophagous flies, beetles and wasp parasitoids have been collected, some of which rare or new for Italy or Paleartic Region. In particular, we report our studies on the american black soldier fly, Hermetia illucens (Diptera: Stratiomyidae), that is showing a heavy competition with the local saprophagous species and is reaching great importance in some man activities and in cattle health.

Postmortem interval (PMI) determined by study sarcophagous biocenoses: three cases from the province of Venice (Italy).

This paper presents and discusses three cases of cadavers found, unburied, in the province of Venice, Northern Italy. In each case, all insect species playing some role in carrion decay processes, both sarcophagous and their predators, found on or in the bodies, were collected and determined. In one case, many larvae of the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae) were found and are reported, for the first time in Italy, as necrophagous. Experimental breeding of some fly species was also carried out in controlled temperature and humidity conditions. In particular, it was of interest to know how the Neotropical black soldier fly modified its life-cycle to adapt to a temperate climate. It was thus possible to establish the rate of larval growth and timing of pupation, emergence, oviposition and hatching in various external conditions. The postmortem interval (PMI) established by identifying the life-cycle stages of dipterofauna were later confirmed in all cases through police investigations and the results of forensic analyses.

Effects of chronic dietary cadmium on hepatic glutathione levels and glutathione peroxidase activity in starlings (Sturnus vulgaris).

The effects of chronic exposure to dietary cadmium on the levels of hepatic glutathione (GSH) and on the activity of the glutathione peroxidase enzymes (GSH-Px) were studied for the first time in starlings (Sturnus vulgaris). Thirty-three individuals (17 females and 16 males) were divided into three groups: One represented the untreated control and two were respectively fed with diets containing 10 and 50 ppm cadmium chloride (CdCl(2)). The total duration of treatment was 22 weeks. The three groups respectively accumulated mean hepatic Cd residues of 2.29, 75.71, and 208.49 ppm. Hepatic GSH increased in the treated groups respectively 24% and 52% in comparison to controls. Total GSH-Px activity in the liver was inhibited in the group fed with 50 ppm, due to inhibition of the selenium-dependent fraction of the enzyme, while the selenium-independent fraction did not change significantly. During the treatment, after 14 weeks of exposure to cadmium, the 50 ppm-treated group showed a 47% decrease of the activity of the selenium-dependent GSH-Px and a 50% increase of the somatic liver index in comparison with controls.

Toxic levels of selenium in enzymes and selenium uptake in tissues of a marine fish.

Acute toxicity of selenium as selenite in Zosterisessor ophiocephalus by ip injection was studied. The 50% lethal dose and 50% lethal time were measured to be 0.29 ppm and 96 h, respectively. Se concentrations in liver, gill, skin and muscle, and Cyt. P450 level, Se-GPx, and Total GPx enzyme activities in liver were also assessed at different doses and times after injection. Starting at 0.3 ppm injected dose, enzyme activities and Se concentration in tissues, but not in muscle, showed significant differences from the control group. A threshold behavior was inferred. Normal conditions of enzyme activities and Se concentration in tissues were restored about 1 wk after injection. Biological elimination half-lives were about 2 d for liver and gill, and 5 d for skin.