519 research outputs found
AUTOMATIC SEAGRASS BANQUETTES DETECTION FROM SURVEILLANCE CAMERA IMAGES WITH DETECTRON2|Rilevamento automatico di banquette di Posidonia con Detectron2 da immagini di telecamere di sorveglianza
No full textSABATO G., SCARDINO G., KUSHABAHA A., CHIRIV Ì M., LUpARELLI A. & SCICCHITANO G., Automatic seagrass banquettes detection from surveillance camera images with Detectron2. (IT ISSN 0391-9838, 2022). In recent years, machine learning and deep learning methodologies have gained increasing attention in various fields of research, including environmental studies. Some algorithms with deep learning can be used to identify coastal features, detect changes over time, and monitor human activities on the coast, providing important information for sustainable coastal management. This study presents the application of the Detectron2 algorithm for monitoring a beach and verifying the presence or absence of stranded seagrass banquettes from video surveillance system images. The algorithm enables quick and automatic detection of these features, provid-ing a valuable tool for beach managers and researchers alike
OPEN ACCESS DATA REPOSITORY OF LATE-PLEISTOCENE AND HOLOCENE PALEO-SHORELINES ALONG THE ANTARCTIC PENINSULA AND SOUTH SHETLAND ISLANDS COASTS
No full textZingaro M., Baroni C., Capolongo D., Mastro-nuZZi g., salvatore M.C., sCiCChitano g. & vaCChi M.,Open access data repository of Late-Pleistocene and Holocene paleo-shorelines along the Antarctic Peninsula and South Shetland Islands coasts. (IT ISSN 0391-9838, 2021).An improved understanding of the chronology of Antarctic ice sheet deglaciation since the Last Glacial Maximum (LGM) represents a fundamental tool to better define the origin of past and future meltwa-ter influx in the global oceans. Relict shorelines and other evidence of past Relative Sea Level (RSL) evolution were widely used to understand past ice sheet history and to improve predictions of climate-controlled sea level evolution. In the last decades, RSL data in the Antarctic region have been mostly produced using a wide range of geomorphic evidence such as beach and marine deposits, marine terraces and isolation ba-sins. However, the lack of a geographic common framework that in-cludes data derived from different sources, limits the accessibility to the information. Here we present a new cartographic approach to cre-ate an open access geodatabase of the postglacial paleo-shorelines by using a standard collecting pattern. Cartographic Antarctica Reposito-ry (CAR) includes RSL data along the coasts of the Antarctic Peninsula and South Shetland Islands. Results show the advantages to use CAR for integrating data and supporting spatial analyses, by representing an easy and usable tool for the improvement of shoreline evolution defini-tion and the planning of Antarctic coast investigations. CAR is dynam-ic repository project that will be further expanded on other Antarctic regions too, integrating fully into the wide reference context of the free access Antarctic datasets
Counteracting sarcopenia: The role of IGF-1 isoforms
No full textSarcopenia, the age-related loss of muscle mass and strength, represents one of the main causes of impaired physical performance and reduced mobility. Thus, understanding the pathogenetic mechanisms of muscle wasting associated with aging has been the objective of numerous studies and represents an important first step for the development of therapeutic approaches [1,2].
Among growth factors, the insulin-like growth factor-1 (IGF-1) have been implicated in the control of skeletal muscle growth, differentiation, and regeneration and has emerged as a growth factor with a remarkably wide range of actions and a tremendous potential as a therapeutic factor in attenuating the atrophy and frailty associated with muscle ageing and diseases [3,4]. In the adult mammals, IGF-1 is principally synthesized in the liver, acting as a systemic growth factor; however, it is also produced in extrahepatic tissues, including skeletal muscle, where it mainly plays an autocrine/paracrine role. The IGF-1 protein is produced by different pre-pro-peptides, whereas two different promoters and differential splicing of the IGF-1 gene create several IGF-1 isoforms, which differ in the N-terminal signal-peptide (Class 1 or 2) and the C-terminal Extension peptide (E-peptide Ea or Eb) [3]. Given the conflicting and still unclear data on effects of different IGF-1 isoforms, a recent study investigated whether the muscle overexpression of either propeptides IGF-1Ea or IGF-1Eb isoform impacts sarcopenia and through which mechanisms each isoform acts [5]. Muscle restricted over-expression of both IGF-1Ea and IGF-1Eb isoforms did not induce any significant change in the circulating IGF-1 levels in young mice compared to age-matched wild type animals. Interestingly, consistent with the physiological decline of IGF-1 plasma levels during aging, a strong reduction of IGF-1 levels was observed in old wild type mice [5]. On the contrary, aged transgenic animals showed unchanged levels of circulating IGF-1 compared to young counterparts, thus resulting higher compared to old wild type mice. It is possible to speculate that IGF-1 isoforms, locally expressed, exert an indirect systemic effect, contributing to the maintenance of circulating IGF-1 levels during postnatal life. Indeed, skeletal muscle has recently been identified as an endocrine organ, able to produce and release cytokines and other peptides, such as the myokines, that act in paracrine, autocrine, or endocrine manner [6]. In this context, muscle can be also a source of circulating IGF-1, based on the evidences that IGF-1 is released from exercising muscle into the blood stream [6]. Thus, we can speculate that the reduction of circulating IGF-1 levels in aged wild type mice could be the result of the morpho-functional alterations occurred in muscle. Conversely, transgenic mice, guaranteeing the muscle expression levels of IGF-1 isoforms even at late post-natal life, preserve the capability of muscle to function as endocrine organ, thus contributing to maintain unaltered the circulating IGF-1 levels.
Of note, IGF-1Ea but not IGF-1Eb was able to promote a pronounced muscle hypertrophy and strength in both young and aged mice [5]. Nevertheless, beside the promotion of muscle growth, both IGF-1Ea and IGF-1Eb were able to counteract sarcopenia, negatively modulating the inflame-aging process and activating relevant pathways considered part of a molecular antiaging system, such as autophagy and PGC-1-mediated signaling, which alteration induces neuromuscular junction degeneration and precocious aging [5,7]. Of interest, and in some way paradoxically, the increased levels of IGF-1Ea, but not IGF-1Eb, was correlated with high ROS production [5]. This data suggests that ROS production is part of the promotion and maintenance of a functional hypertrophic phenotype, induced by IGF-1Ea, and supports the evidence that reactive oxygen species are not merely damaging agent but useful signaling molecules to regulate growth, proliferation, differentiation, and adaptation, at least within physiological concentration. Of note, the IGF-1Ea mice were able to minimize oxidative damage in senescent muscle up-regulating, through PGC1-α activation, NRF-2 protein, the master regulator of antioxidant defense [8] and Sirt-1, a factor involved in growth regulation, stress response, endocrine signaling, and extended lifespan.
Moreover, the maintenance of hypertrophic phenotype by IGF-1Ea promoted the activation of additional pathways, such as AMPK, a factor involved in the maintenance of whole-body energy balance and an energy sensor controlling glucose and lipid metabolism. These data are consistent with a model (Figure 1) in which muscle expression of either IGF-1Ea or IGF-1Eb, activating a series of anabolic and compensatory pathways, are able to counteract sarcopenia, preventing muscle loss, strength, and alteration in muscle-nerve interaction. It is also plausible that muscle expression of IGF-1 isoforms, preserving skeletal muscle, might maintain the youth not only of muscle tissue but also of the entire organism, by promoting a local effort activity for a global impact benefit
Coastal retreat and marine flooding scenario for 2100: A case study along the coast of Maddalena peninsula (southeastern Sicily)
No full textANZIDEI M., SCICCHITANO G., TARASCIO S., DE GUIDI G., MONACO C., BARRECA G., MAZZA G., SERPELLONI E. & VECCHIO A., Coastal retreat and marine flooding scenario for 2100: a case study along the coast of Maddalena Peninsula (southeastern Sicily). (IT ISSN 0391-9838, 2018). The coastal area of southeastern Sicily (Italy) is undergoing weak land subsidence, heavy coastal retreat, land flooding and exposed to severe storms associated with high-waves, also in consequence of the global sea level rise, which is expected to raise even more that 1 m by 2100 AD depending on different estimates. This value will be even larger in subsiding coasts, entailing widespread environmental changes, coastal retreat, marine flooding and loss of land, which will be subtracted to human activities. To understand the impact of rising sea level on the coast of Maddalena Peninsula, near the town of Siracusa, we realized a very high resolution Digital Terrain Model (DTM) through aerial photogrammetric surveys, obtained by Unmanned Aerial Vehicles (UAV) on which we projected the expected coastline for 2100 AD. Here we show a detailed marine flooding scenario for 2100, as generated from: i) high resolution DTM, ii) rate of land subsidence from GPS data and iii) predicted sea level projections from the IPCC AR5 reports (RCP2.6 and RCP8.5). Our analysis estimates a maximum relative sea level rise at 0.20 m and 0.65 m for 2050 AD and 2100 AD, respectively for AR 8.5 scenario. The increased sea levels will cause relevant morphological changes to the investigated coast with a maximum beach retreat of 27 m and a loss of land of 7400 m2, affecting building integrity and people safety
Counteracting muscle wasting in aging and neuromuscular diseases: the critical role of IGF-1.
No full textMost muscle pathologies are characterized by the progressive loss of muscle tissue due to chronic degeneration combined with the inability of regeneration machinery to replace the damaged muscle. These pathological changes, known as muscle wasting, can be attributed to the activation of several proteolytic systems, such as calpain, ubiquitin-proteasome and caspases, and to the alteration in muscle growth factors. Among them, insulin-like growth factor-1 (IGF-1) has been implicated in the control of skeletal muscle growth, differentiation, survival, and regeneration and has been considered a promising therapeutic agent in staving off the advance of muscle weakness. Here we review the molecular basis of muscle wasting associated with diseases, such as sarcopenia, muscular dystrophy and Amyotrophic Lateral Sclerosis, and discuss the potential therapeutic role of local IGF-1 isoforms in muscle aging and diseases
Karstic caves and submerged paleo-shorelines in the coastal area between Capo Santa Panagia and Ognina (Siracusa, south-eastern Sicily)
No full textThe aim of this work is the detailed survey of the submerged area in front of the shoreline between Capo S. Panagia e Ognina (Siracusa), in order to reconstruct the lateral extension and the continuity of the submerged morphological elements and to define their genesis and temporal evolution. This coastal stretch is characterized by the occurrence of several raised paleo-shorelines, related to Late Quaternary high-stands. They are represented by cliffs and abrasion platforms carved on a Miocene-Pleistocene carbonatic succession and are often linked to karstic levels (caves, channels, siphons, etc.). Several speleothems, such as stalagmites, stalactites, columns, cave pearls, have been found in the caves. The submerged area is characterized by the same morphological features. The sea-bottom is, in fact, characterized by at least two palaeo-cliffs of marine origin, the shallower one located at depths between -9÷12 m and -20÷22 m, the deeper one located at depths between -20÷25 m and -40÷45 m. The scarp located between -9÷12 m and - 20÷22 m is well preserved and shows a continuity of about 20 km. The scarp located between -20÷25 m and -40÷45 m is more discontinuous and steeper. Several caves, channels and siphons, characterized by the occurrence of continental fossilized speleothems, have been found along these scarps, probably linked to palaeo-karstic levels. The detailed topographic survey of two caves has been carried out and a stalagmite has been sampled in order to determine its age and to reconstruct the relationships between sea-level rise and vertical tectonic motion of the area. The morphological analysis and the first dating results suggest that the two submerged palaeo-shorelines can be interpreted as the effect of Late Pleistocene sea level stands. At present they are submerged as a consequence of the sudden Holocene sea-level rise
More insecure and less paid? The effect of perceived job insecurity on wage distribution
No full textThis article employs a Counterfactual Decomposition Analysis (CDA) using both a semi-parametric and a non-parametric method to examine the pay gap due to perceived job insecurity over the entire wage distribution of dependent workforce in Italy. Using the 2015 INAPP Survey on Quality of Work, our results exhibit a mirror J-shaped pattern in the pay gap between secure and insecure workers, with a significant sticky floor effect, i.e. a greater effect of job insecurity at the lowest quantiles. This pattern is mainly due to the characteristics effect, while the relative incidence of the coefficient component accounts roughly for 22% up to 36% of the total difference, being more relevant at the bottom of the wage distribution
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