644 research outputs found
Occurrence of the scalloped ribbonfish Zu cristatus(Lampridiformes) in coastal waters of the central Tyrrhenian Sea, Italy
No full textThe occurrence of two individuals of Zu cristatus at 2 m depth in coastal waters of the Gulf of Castellamare (Tyrrhenian Sea, Italy) together with records of this rare pan-Oceanic mesopelagic species is reported. Analyses of two mitochondrial genes (12 s and 16 s; 936 bp) revealed a 2.6% sequence divergence between Mediterranean and Pacific (Japanese) samples of the species
Harmful and beneficial properties of cyanotoxins: Two sides of the same coin
No full text: Cyanotoxins are by definition "harmful agents" produced by cyanobacteria. Their toxicity has been extensively studied and reviewed over the years. Cyanotoxins have been commonly classified, based on their poisonous effects on mammals, into three main classes, neurotoxins, hepatotoxins and dermatotoxins, and, considering their chemical features, mainly identified as peptides, alkaloids and lipopolysaccharides. Here we propose a broader subdivision of cyanotoxins into eight distinct classes, taking into account their molecular structures, biosynthesis and modes of action: alkaloids, non-ribosomal peptides, polyketides, non-protein amino acids, indole alkaloids, organophosphates, lipopeptides and lipoglycans. For each class, the structures and primary mechanisms of toxicity of the main representative cyanotoxins are reported. Despite their powerful biological activities, only recently scientists have considered the biotechnological potential of cyanotoxins, and their applications both in medical and in industrial settings, even if only a few of these have reached the biotech market. In this perspective, we discuss the potential uses of cyanotoxins as anticancer, antimicrobial, and biocidal agents, as common applications for cytotoxic compounds. Furthermore, taking into account their mechanisms of action, we describe peculiar potential bioactivities for several cyanotoxin classes, such as local anaesthetics, antithrombotics, neuroplasticity promoters, immunomodulating and antifouling agents. In this review, we aim to stimulate research on the potential beneficial roles of cyanotoxins, which require interdisciplinary cooperation to facilitate the discovery of innovative biotechnologies
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Fantastic Architecture and the Building of Europe in Valerio Evangelisti's Eymerich Fiction
No full textConcomitant with the horizontal expansion of EU territory through physical and political enlargement is a genealogy narrative, which emphasizes the ostensible roots of Europeanness in classical antiquity and Christianity. In the face of this sanitized genealogy, which lies at the heart of the European constitutional project, a range of alternative and more inclusive narratives circulate in contemporary European popular fiction. This paper focuses on a series of fantasy novels by the Italian author Valerio Evangelisti, featuring Inquisitor Eymerich as hero-investigator. In his highly popular novels, Evangelisti seeks to uncover layers of shared historical memory untainted with post-Enlightenment rhetoric.
The central architectural tropes of Evangelisti’s imaginary world are those of a castle and a convent, epitomizing the temporal and sacral power in European history. Each isolated from its outside environment and built on layer upon layer of subterranean chambers and corridors, the castle and the convent conceal a past quite different from the one championed in the official European genealogy. Memories of pagan worship and Islamic or Judaic learning – banished from the official rhetoric – continue to thrive, dark and threatening, in the subterranean strata of Evangelisti’s European edifice. Evangelisti thus provides an incisive critique of the official European story of origin, which threatens to suppress any alternative visions of European history or unorthodox avenues for European identity formation
Global Changes Alter the Successions of Early Colonizers of Benthic Surfaces
No full textThe successions of benthic communities over time are strongly influenced by the first colonizers, because surface associations are facilitated by modifications to the adhesive properties promoted by primary colonizers, such as bacteria, protozoans, diatoms, algal propagules, spores, and invertebrate larvae. Bacteria are often the first colonizers on marine submerged surfaces, both organic (e.g., algae, seagrasses and invertebrates) and inorganic. However, they are promptly followed by diatoms and other microorganisms. Consequently, diatoms may represent key elements in the determination of the colonization patterns, although the development of epiphytic communities is a dynamic process influenced by several factors, including nutrient availability, the ability to synthesize and secrete extracellular material, the competition among species and the influence of grazers on individual colonizers. The process may be drastically impacted by global warming and ocean acidification due to the increasing atmospheric levels of CO2. The impact of such global stressors on benthic ecosystems, especially on the primary microphytobenthic assemblages, is still poorly investigated, and may have deleterious consequences for the benthic successions. In this review, we analyze the adhesion patterns of marine microorganisms according to their surface features and the effects of global changes on critical pioneer colonizers, such as the benthic diatoms. The results are remarkable, as they highlight emergent concerns in ecosystem conservation and the prediction of benthic communities
Behavioural Responses of the Colonial Sea Squirt Botrylloides violaceus Oka to Suspended Food Micro-Particles in Laboratory Cultures
No full textViolet sea squirts are noteworthy model organisms, because they provide insights into various physiologic processes, including cell senescence, ageing, apoptosis and allorecognition. Consequently, their culture is critical to permit experimental studies. Most papers refer to short periods of rearing using various feeds, both living and conserved, missing a formal justification for their use or indications of their actual nutritional value. Here, we use two behavioural responses—the percentage of open siphons and the frequency of zooid contractions—as compared to the abundance of suspended microparticles during feeding tests, to identify feeds able to promote filter-feeding. The results will enable to formulate compound diets that maximise positive physiological responses. Our tests demonstrated that plant items, such as dry microalgae and cyanobacteria (Arthrospira platensis, commercially known as Spirulina), along with living planktonic Haptophyta (Isochrysis galbana), trigger clear positive reactions, represented by a higher frequency of zooid contractions and larger proportions of open siphons. These responses correspond to decreases in the concentrations of suspended microparticles during the experiment and indicate higher filter-feeding activity. In contrast, feeds commonly administered to colonies, such as milk powder, dried eggs and artificial plankton, triggered negative behavioural responses, and their intake was lower during the feeding trials
Marine Demospongiae: A Challenging Treasure of Bioactive Compounds
No full textIn the last decades, it has been demonstrated that marine organisms are a substantial source of bioactive compounds with possible biotechnological applications. Marine sponges, in particular those belonging to the class of Demospongiae, have been considered among the most interesting invertebrates for their biotechnological potential. In this review, particular attention is devoted to natural compounds/extracts isolated from Demospongiae and their associated microorganisms with important biological activities for pharmacological applications such as antiviral, anticancer, antifouling, antimicrobial, antiplasmodial, antifungal and antioxidant. The data here presented show that this class of sponges is an exciting source of compounds, which are worth developing into new drugs, such as avarol, a hydroquinone isolated from the marine sponge Disidea avara, which is used as an antitumor, antimicrobial and antiviral drug
Relating trophic resources to community structure: a predictive index of food availability
No full textThe abundance and the distribution of trophic resources available for consumers influence the productivity and the diversity of natural communities. Nevertheless, assessment of the actual abundance of food items available for individual trophic groups has been constrained by differences in methods and metrics used by various authors. Here we develop an index of food abundance, the framework of which can be adapted for different ecosystems. The relative available food index (RAFI) is computed by considering standard resource conditions of a habitat and the influence of various generalized anthropogenic and natural factors. RAFI was developed using published literature on food abundance and validated by comparison of predictions versus observed trophic resources across various marine sites. RAFI tables here proposed can be applied to a range of marine ecosystems for predictions of the potential abundance of food available for each trophic group, hence permitting exploration of ecological theories by focusing on the deviation from the observed to the expected
Hermann Kant. Ein bio- bibliografisches Profil
No full textThe proximity to the power apparatus has cast dark shadows on the literary work of Hermann Kant, who is regarded as one of the most read authors of the GDR. Valerio Furneri embeds Kant's life and work in the all-German context of the 20th century and reinterprets his classics such as Die Aula or Der Aufenthalt. The author does not pursue the claim to rehabilitate the GDR, nor to trivialise Kant's role in it. Instead, the attempt is made to look at Kant's entire work from a temporal distance and to re-evaluate it. Through his works, Kant was able to accompany and depict not only the German-German history, but also European history.Die Nähe zum Machtapparat hat dunkle Schatten auf das literarische Werk von Hermann Kant, der als meistgelesener Schriftsteller der DDR gilt, geworfen. Valerio Furneri bettet Kants Leben und Werk in den gesamtdeutschen Kontext des 20. Jahrhunderts ein und interpretiert vor diesem Hintergrund Klassiker wie Die Aula oder Der Aufenthalt neu. Der Autor verfolgt dabei weder den Anspruch, die DDR zu rehabilitieren, noch Kants Rolle darin kleinzureden. Stattdessen wird der Versuch unternommen, Kants Gesamtwerk aus zeitlicher Distanz zu betrachten und neu zu bewerten. Durch seine Werke gelang es Kant nämlich nicht nur die deutsch-deutsche, sondern auch die europäische Geschichte zu begleiten und abzubilden
Hermann Kant. Ein bio- bibliografisches Profil
No full textThe proximity to the power apparatus has cast dark shadows on the literary work of Hermann Kant, who is regarded as one of the most read authors of the GDR. Valerio Furneri embeds Kant's life and work in the all-German context of the 20th century and reinterprets his classics such as Die Aula or Der Aufenthalt. The author does not pursue the claim to rehabilitate the GDR, nor to trivialise Kant's role in it. Instead, the attempt is made to look at Kant's entire work from a temporal distance and to re-evaluate it. Through his works, Kant was able to accompany and depict not only the German-German history, but also European history.Die Nähe zum Machtapparat hat dunkle Schatten auf das literarische Werk von Hermann Kant, der als meistgelesener Schriftsteller der DDR gilt, geworfen. Valerio Furneri bettet Kants Leben und Werk in den gesamtdeutschen Kontext des 20. Jahrhunderts ein und interpretiert vor diesem Hintergrund Klassiker wie Die Aula oder Der Aufenthalt neu. Der Autor verfolgt dabei weder den Anspruch, die DDR zu rehabilitieren, noch Kants Rolle darin kleinzureden. Stattdessen wird der Versuch unternommen, Kants Gesamtwerk aus zeitlicher Distanz zu betrachten und neu zu bewerten. Durch seine Werke gelang es Kant nämlich nicht nur die deutsch-deutsche, sondern auch die europäische Geschichte zu begleiten und abzubilden
Effects of biodegradable-based microplastics in Paracentrotus lividus Lmk embryos: Morphological and gene expression analysis
No full textPlastic pollution is a remarkable environmental issue. In fact, plastic is widespread in the lifetime and serious environmental problems are caused by the improper management of plastic end of life, being plastic litter detected in any environment. Efforts are put to implement the development of sustainable and circular materials. In this scenario, biodegradable polymers, BPs, are promising materials if correctly applied and managed at the end of life to minimize environmental problems. However, a lack of data on BPs fate and toxicity on marine organisms, limits their applicability. In this research, the impact of microplastics obtained from BPs, BMPs, were analyzed on Paracentrotus lividus. Microplastics were produced from five biodegradable polyesters at laboratory scale by milling the pristine polymers, under cryogenic conditions. Morphological analysis of P. lividus embryos exposed to polycaprolactone (PCL), polyhydroxy butyrate (PHB) and polylactic acid (PLA) showed their delay and malformations, which at molecular level are due to variation in expression levels of eighty-seven genes involved in various cellular processes, such as skeletogenesis, differentiation and development, stress, and detoxification response. Exposure to poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA) microplastics showed no detectable effects on P. lividus embryos. These findings contribute with important data on the effect of BPs on the physiology of marine invertebrates
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