920 research outputs found

    Effects of grazer diversity on marine microphytobenthic biofilm: a ‘tug of war’ between complementarity and competition

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    Species loss is one of the most striking problems related to human-driven environmental changes. Nevertheless, biodiversity and ecosystem functioning experiments have mainly focused on primary producers, paying less attention to the consequences of changing diversity at higher trophic levels. We performed a field experiment using cage enclosures to test the effects of species richness, identity and density of gastropod grazers on the photosynthetic efficiency and biomass of intertidal biofilm on an exposed rocky shore in the northwest Mediterranean. The diversity and composition of intertidal grazers affected the photosynthetic efficiency of biofilm with only negligible effects on biomass. Individual species showed strong identity effects. In assemblages of 2 or more species, positive or negative complementarity effects occurred. The magnitude of the ecosystem response is expected to depend on the particular species assemblage and its density, which will determine whether niche partitioning or competition is the prevailing process. Grazer preference in specific components of biofilm, characterized by different photosynthetic efficiency and competitive abilities, might explain concomitant changes in photosynthetic efficiency and comparable levels in biomass among treatments. The effects of grazers declined following the natural trend of decreasing biomass of biofilm during the study period, highlighting the importance of considering temporal variability in the effects of biodiversity on ecosystem functioning. This work emphasizes the key role of species identity to predict effects on their resources and ecosystem functioning.This work was partially supported by the University of Pisa

    COVAX as a Global Public Health initiative

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    Amid the chaos that COVID 19 was causing, several actors created a partnership to try to lessen the impact of the pandemic. The COVAX Facility was meant to be a mechanism for global equitable access to vaccines. With ambitious goals and promises, it relied a lot on the solidarity and cooperation between countries. This policy paper intends to understand the need for the international community in providing Global Public Health, to analyze the weaknesses and strengths of COVAX, and also, to offer recommendation on how to improve it. This was done through the analysis of about 53 materials, including policy and academic papers, reports, databases and journalistic sources. After revaluating the creation and development of COVAX, some flaws were found in its structure and implementation. Some of the main issues were allocation frameworks, transparency, solidarity framing, funding, accessibility, nationalism, and a restricted manufacturing base. These and other issues were addressed in the last chapter with the final recommendations. Despite it being aimed at COVAX's coordinators, it can also be used by other organizations and partnerships that want to have a base for other Global Public Health initiativ

    Amiata donkey milk chain: animal health evaluation and milk quality

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    This study presents a investigation into the animal health and quality of Amiata donkey milk for human consumption. Thirty one lactating dairy jennies were examined. The following samples were collected: faecal samples from the rectum of animals for parasitological examination; cervical swabs for the detection of bacteria causing reproductive disorders; and blood samples for serological diagnosis of main zoonotic (Brucella spp., Leptospira spp.) and donkey abortion agents (Brucella spp., Leptospira spp., Salmonella abortus equi, Equine viral arterithis virus, Equine herpesvirus type 1). In addition, individual milk samples were collected and analyzed for mastitis-causing pathogens and milk quality. Regarding animal health, we detected a high prevalence of strongyle parasites in donkeys. It is very important to tackle parasitic diseases correctly. Selective control programmes are preferable in order to reduce anthelmintic drug use. For dairy donkeys, withdrawal periods from anthelmintic drugs need to be carefully managed, in accordance with EU and national regulations. The isolation of Staphylococcus aureus in milk highlights the importance of preventing contamination during milking, by adopting appropriate hygiene and safety practices at a farm level. Amiata donkey milk lysozyme actvity was high compared to cow’s milk, contribuiting to the inhibitory activity against certain bacteria. Donkey milk was characterized by a high lactose content, low caseins, low fat, higher levels of unsaturated fatty acids compared to ruminant milks. Unsaturated fatty acids and omega 3 fatty acids in particular have become known for their beneficial health effect, which is favourable for human diet. These characteristics make it suitable for infants and children affected by food intolerance/allergies to bovine milk proteins and multiple food allergies as well as for adults with dyslipidemias and in the prevention of cardiovascular disease

    Multifractal spatial distribution of epilithic microphytobenthos on a Mediterranean rocky shore

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    Understanding how patterns and processes relate across spatial scales is one of the major goals in ecology. 1/f models have been applied mostly to time series of environmental and ecological variables, but they can also be used to analyse spatial patterns. Since 1/f noise may display scale-invariant behaviour, ecological phenomena whose spatial variability shows 1/f type scaling are susceptible to further characterization using fractals or multifractals. Here we use spectral analysis and multifractal techniques (generalized dimension spectrum) to investigate the spatial distribution of epilithic microphytobenthos (EMPB) on rocky intertidal surfaces. EMPB biomass was estimated from calibrated colour-infrared images that provided indirect measures of rock surface chlorophyll a concentration, along two 8-m and one 4-m long transects sampled in January and November 2012. Results highlighted a pattern of spectral coefficient close to or greater than one for EMPB biomass distribution and multifractal structures, that were consistent among transects, implying scale-invariance in the spatial distribution of EMPB. These outcomes can be interpreted as a result of the superimposition of several biotic and abiotic processes acting at multiple spatial scales. However, the scale-invariant nature of EMPB spatial patterns can also be considered a hallmark of self-organization, underlying the possible role of scale-dependent feedback in shaping EMPB biomass distribution.This work is part of a requirement for a PhD by MDB and was partially supported by the Univ. of Pisa and by the FP 7 EU project VECTORS “VECTORS of Change in Oceans and Seas Marine Life, Impact on Economic Sectors”. CS was supported by a postdoctoral grant from the Alfonso Martin Escudero Foundation from Spain

    The Italian Agreement between the Government and the Regional Authorities: National Guidelines for AAI and Institutional Context

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    Animal-assisted interventions (AAI) have developed considerably in the last half century, prompting various private and public realities dealing with AAI worldwide to work on and establish standards and best practice. However, AAI are still far from being regulated harmoniously. In this context, Italy offers a unique example at world level: here the spread of AAI has set in motion an ethical and legal reflection that led to the creation of the Italian National Reference Centre for AAI (NRC AAI) by ministerial decree in 2009 and the approval of National Guidelines for AAI in 2015. The Italian legislation on AAI is based on the One Health approach, which has been part of Italian health culture and institutions since the Renaissance. The synergy between human and veterinary medicine is the core of this theme: in other words, One Health represents a multidisciplinary approach aimed at best protecting the health and well-being of all those who share our planet. In Italy, human and veterinary medicine have both been placed under the umbrella of the Ministry of Health since its establishment in 1958. The same idea of collaboration is at the heart of the Italian legislative approach to the AAI field, given the inherent multidisciplinarity of these interventions. This applies to all indications provided by the National Guidelines, for example the distinction between the various types of interventions, the animal species involved, the roles within the multidisciplinary team, and the training programs for each professional figure. In addition, the National Guidelines are intended to be amendable according to the needs arising over time from daily practice: in fact, the constant contact and dialogue between institutions and AAI professionals is another pillar of the Italian approach

    Cats’ and dogs’ welfare: text mining and topics modeling analysis of the scientific literature

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    Animal welfare is a field with increasing significance and has been raising huge concerns of the public and the political stage. Cats and dogs possess an important role in human life, but their welfare is not always secured from a legal aspect. This review aimed to describe the evolution and geographical distribution of “cats and dogs” and “puppies and kittens” welfare literature over the last 40 years, distinguish the main research topics studied and highlight gaps in knowledge. A search using Scopus¼ was performed with different search strings and predetermined filters as time range, language, and subject area. A total of 2,725 scientific literature records were retrieved but only the ones that referred to cats and dogs’ welfare aspects were retained. The final 1,775 records were processed through descriptive statistics, and text mining and topic analysis procedures were performed on their titles and abstracts. The results showed that the number of studies has been increasing, especially in Europe and North America. “Shelter” was the most frequent word, followed by “behavior,” “owner” and “adopt.” The nine topics that emerged from the analysis were breeding, stress and housing conditions, welfare and pain assessment, public health, shelter management and euthanasia, behavioral problems, health issues and management, human-animal interaction, and owners’ and veterinarians’ perceptions. While stress and housing conditions, public health, and owners’ and veterinarians’ perceptions were the most studied topics, human-animal interaction was the least studied. This review confirmed the increasing research and interest in cats’ and dogs’ welfare and showed gaps in knowledge where further studies are needed

    Antifungal activity and biochemical profiling of exudates from germinating maize Nostrano di Storo local variety

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    Plant pathogens are responsible for important damages to valuable crops causing important economic losses. Agrobiodiversity protection is crucial for the valorization of local varieties that could possess higher resistance to biotic and abiotic stress. At the beginning of germination, seeds are susceptible to pathogens attacks, thus they can release endogenous antimicrobial compounds of different natures in the spermosphere, to contrast proliferation of microorganisms. The work aimed at characterizing the maize of local variety Nostrano di Storo seed exudates secreted during the first phases of germination, to identify compounds active in the defense towards pathogens. Storo seed exudates were proven to inhibit F. verticilloides germination. In order to investigate the cause of the described effect, compositional profiling of the exudates was performed through NMR, lipidomic, and proteomic analyses. This study suggests an important role of microbial endophytic communities in the protection of the seed during the early phases of the germination process and their interplay with fatty acids released by the seeds, rather than a specific antifungal compound. The valorization of agronomically acceptable maize lines with pre-harvest enhanced resistances to pathogens contamination could lead, in the near future, to commercially available varieties potentially requiring more limited chemical protective treatments

    A conserved juxtacrine signal regulates synaptic partner recognition in Caenorhabditis elegans

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    <p>Abstract</p> <p>Background</p> <p>An essential stage of neural development involves the assembly of neural circuits via formation of inter-neuronal connections. Early steps in neural circuit formation, including cell migration, axon guidance, and the localization of synaptic components, are well described. However, upon reaching their target region, most neurites still contact many potential partners. In order to assemble functional circuits, it is critical that within this group of cells, neurons identify and form connections only with their appropriate partners, a process we call synaptic partner recognition (SPR). To understand how SPR is mediated, we previously developed a genetically encoded fluorescent trans-synaptic marker called NLG-1 GRASP, which labels synaptic contacts between individual neurons of interest in dense cellular environments in the genetic model organism <it>Caenorhabditis elegans</it>.</p> <p>Results</p> <p>Here, we describe the first use of NLG-1 GRASP technology, to identify SPR genes that function in this critical process. The NLG-1 GRASP system allows us to assess synaptogenesis between PHB sensory neurons and AVA interneurons instantly in live animals, making genetic analysis feasible. Additionally, we employ a behavioral assay to specifically test PHB sensory circuit function. Utilizing this approach, we reveal a new role for the secreted UNC-6/Netrin ligand and its transmembrane receptor UNC-40/Deleted in colorectal cancer (DCC) in SPR. Synapses between PHB and AVA are severely reduced in <it>unc-6 </it>and <it>unc-40 </it>animals despite normal axon guidance and subcellular localization of synaptic components. Additionally, behavioral defects indicate a complete disruption of PHB circuit function in <it>unc-40 </it>mutants. Our data indicate that UNC-40 and UNC-6 function in PHB and AVA, respectively, to specify SPR. Strikingly, overexpression of UNC-6 in postsynaptic neurons is sufficient to promote increased PHB-AVA synaptogenesis and to potentiate the behavioral response beyond wild-type levels. Furthermore, an artificially membrane-tethered UNC-6 expressed in the postsynaptic neurons promotes SPR, consistent with a short-range signal between adjacent synaptic partners.</p> <p>Conclusions</p> <p>These results indicate that the conserved UNC-6/Netrin-UNC-40/DCC ligand-receptor pair has a previously unknown function, acting in a juxtacrine manner to specify recognition of individual postsynaptic neurons. Furthermore, they illustrate the potential of this new approach, combining NLG-1 GRASP and behavioral analysis, in gene discovery and characterization.</p

    Early-life exposure to environmentally relevant concentrations of triclocarban impairs ocular development in zebrafish larvae

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    Triclocarban (TCC), is an antimicrobial component in personal care products and it is one of the emerging contaminants since it has been detected in various environmental matrices. Its presence in human cord blood, breast milk, and maternal urine raised issues about its possible impact on development and increased concerns about the safety of daily exposure.This study aims to provide additional information about the effects of zebrafish early-life exposure to TCC on eye development and visual function. Zebrafish embryos were exposed to two concentrations of TCC (5 and 50 mu g/L) for 4 days. TCC-mediated toxicity was assessed in larvae at the end of exposure and in the long term (20 days post fertilization; dpf), through different biological end-points. The experiments showed that TCC exposure influences the retinal architecture. In 4 dpf treated larvae, we found a less organized ciliary marginal zone, a decrease in the inner nuclear and inner plexiform layers, and a decrease in the retinal ganglion cell layer. Photoreceptor and inner plexiform layers showed an increase in 20 dpf larvae at lower and both concentrations, respectively. The expression levels of two genes involved in eye development (mitfb and pax6a) were both decreased at the concentration of 5 mu g/L in 4 dpf larvae, and an increase in mitfb was observed in 5 mu g/L-exposed 20 dpf larvae. Interestingly, 20 dpf larvae failed to discriminate between visual stimuli, demonstrating notable visual perception impairments due to compound. The results prompt us to hypothesize that early-life exposure to TCC may have severe and potentially long-term effect on zebrafish visual function
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