Macroinvertebrates assembly in a patchy environment: centrality measures for the spatial network of detritus-based communities

Spatial patterns influence the persistence of populations and communities, giving useful insights on the mechanisms that confer robustness to ecological networks. The mechanisms that regulate the spatial distribution of species are related to the ability of populations to respond to spatio-temporal variations of ecological conditions, contributing to network structure and dynamic of persisting communities. We applied the framework of complex network to study the colonization process of Phragmites australis leaf detritus in six different pools in the patchy aquatic environment of Tarquinia saltern (central Italy). We used the colonization data of macroinvertebrates on leaf detritus assigning a link between two taxa if they shared a common pool, and measured their positional importance within the network. We found high clustering and short path lenght among nodes that is representative of small-world pattern, showing the relationship between robustness and nodes synchronicity in network attachment dynamics. Here we show how the identification of local (individual use of substrates by macroinvertebrates) and global (network properties) patterns in community structure could be the key to better understand the ecology, evolution and management of complex ecological network

Drought effects on freshwater macroinvertebrate community in the Mediterranean: ecological network analysis as an innovative tool for bioassessment

Freshwater ecosystems in the Mediterranean region are under high pressure. Predictions point to an increase in water scarcity with negative implications to the sustainability of freshwater resources. Models at the local and regional level forecast that water stress may become particularly acute in the south-west USA, the Mediterranean Basin and the Middle East. On the other hand, at the global scale, water demand has doubled over the last fifty years due to increased demography and water intensive use. It is therefore essential to develop tools able to quickly detect environmental drought effects and establish measures that minimize their associated socio-economic impacts. From an ecological perspective, droughts are considered to be a ‘ramp disturbance’, whose effects on biological communities is influenced by factors such as timing, duration, intensity and the presence of refuges. As flows decrease, habitat space is generally reduced; organisms respond to these conditions by continuous colonisation–extinction processes that often lead to a reduction in their density or even extirpation. Network analysis can be a powerful tool to obtain useful information about the pattern of species incidence and/or species co-occurrence, revealing complex direct and indirect effects of stressors on biotic communities, beyond the simple loss or gain of species. Here, we tested how drought dynamics in rivers influence the modular partitioning of macroinvertebrates co-occurrence networks using different datasets within the Mediterranean region, covering different spatial and temporal drought surveys. We postulate that under severe drought events the contraction of available habitats/resources leads to an increasing modularity. The higher modular partitioning of networks clearly indicate that the pattern of species co-occurrence is influenced in a nontrivial way by the drought period, influencing how each species aggregate or segregate in space and time. Our findings suggest that network modularity is a key tool for biomonitoring, able to discriminate the role of drought in different datasets and giving us better information than metrics from standard methods, with the advantage of requiring the same sampling efforts as current monitoring procedures. We advocate the use of such tool to improve our capacity to quickly detect environmental drought effects and accurately assess the ecological status of Mediterranean streams under multiple stressor

Probiotics in the treatment of diverticular disease. A systematic review

BACKGROUND AND AIMS: Diverticular disease is a common gastrointestinal condition. Low-grade inflammation and altered intestinal microbiota have been identified as factors contributing to abdominal symptoms. Probiotics may lead to symptoms improvement by modifying the gut microbiota and are promising treatments for diverticular disease. The aim of this study was to systematically review the efficacy of probiotics in diverticular disease in terms of remission of abdominal symptoms and prevention of acute diverticulitis. METHODS: According to PRISMA, we identified studies on diverticular disease patients treated with probiotics (Pubmed, Embase, Cochrane). The quality of these studies was evaluated by the Jadad scale. Main outcomes measures were remission of abdominal symptoms and prevention of acute diverticulitis. RESULTS: 11 studies (2 double-blind randomized placebo-controlled, 5 open randomized, 4 non-randomized open studies) were eligible. Overall, diverticular disease patients were 764 (55.1% females, age 58-75 years). Three studies included patients with symptomatic uncomplicated diverticular disease, 4 studies with symptomatic uncomplicated diverticular disease in remission, 4 studies with complicated or acute diverticulitis. Mainly (72.7%) single probiotic strains had been used, most frequently Lactobacilli. Follow-up ranged from 1 to 24 months. Interventions were variable: in 8 studies the probiotic was administered together with antibiotic or anti-inflammatory agents and compared with the efficacy of the drug alone; in 3 studies the probiotic was compared with a high-fibre diet or used together with phytoextracts. As an outcome measure, 4 studies evaluated the occurrence rate of acute diverticulitis, 6 studies the reduction of abdominal symptoms, and 6 studies the recurrence of abdominal symptoms. Meta-analysis on the efficacy of probiotics in diverticular disease could not be performed due to the poor quality of retrieved studies. CONCLUSION: This systematic review showed that high-quality data on the efficacy of probiotics in diverticular disease are scant: the available data do not permit conclusions. Further investigation is required to understand how probiotics can be employed in this condition

The Mediterranean European hake, Merluccius merluccius: Detecting drivers influencing the Anisakis spp. larvae distribution

The European hake Merluccius merluccius is one of the most commercially important and widely distributed fish species, occurring both in European and Mediterranean Sea fisheries. We analyzed the distribution and infection rates of different species of Anisakis in M. merluccius (N = 1130 hakes), by site of infection in the fish host (viscera, dorsal and ventral fillets) from 13 different fishing grounds of the Mediterranean Sea (FAO area 37). The fillets were examined using the UV-Press method. A large number of Anisakis specimens (N = 877) were identified by diagnostic allozymes, sequence analysis of the partial EF1 α-1 region of nDNA and mtDNA cox2 gene. Among these, 813 larvae corresponded to A. pegreffii, 62 to A. physeteris, 1 to A. simplex (s. s.), whereas one resulted as a F1 hybrid between A. pegreffii and A. simplex (s. s.). Remarkably high levels of infection with A. pegreffii were recorded in hakes from the Adriatic/Ionian Sea compared to the fish of similar length obtained from the western Mediterranean fishing grounds. A positive correlation between fish length and abundance of A. pegreffii was observed. Concerning the localization of A. pegreffii larvae in the fish, 28.3% were detected in the liver, 62.9% in the rest of the viscera, 6.6% in the ventral part of the flesh, whereas 2.1% in the dorsal flesh

Larval migration of the zoonotic parasite Anisakis pegreffii (Nematoda: Anisakidae) in European anchovy, Engraulis encrasicolus: Implications to seafood safety

n/

Zefiro - Technology and Innovation against Covid-19

Zefiro in an electro-ventilated mask made up of custom designed elements and other widely-available components. Specifically, the frame has been designed as structural element that ensures the correct positioning of the mask. The other standard components perform the functions of isolation and individual protection, as well as introducing air into the mask

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements