26 research outputs found

    The Effect of Passive Exoskeleton on Shoulder Muscles Activity during Different Static Tasks

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    In this study we used the bipolar surface electromyography to investigate whether a passive exoskeleton reduces the degree of activity of shoulder muscles. Twelve young healthy volunteers participated in the study. Subjects were asked to hold four different static postures: (P1) shoulder abducted at 90°, elbow flexed at 90°, elbow pronated at 90°; (P2) shoulder flexed at 90°, elbow flexed at 90°, elbow pronated at 90°; (P3) shoulder flexed at 90°, elbow pronated at 90°; (P4) shoulder abducted at 90°, elbow pronated at 90°. Subjects maintained each posture for 20 seconds five consecutive times, with a rest time in-between of 20 seconds. Surface EMG signals were collected from anterior, medial and posterior deltoids and upper trapezius muscles. Our main statistical results showed a significant (p < 0.05) attenuation effect of exoskeleton on the RMS amplitude computed for all muscles evaluated, though not for all postures. For the anterior, medial deltoids and upper trapezius a lower level of activity was observed in all postures with than without exoskeleton, while for posterior deltoid only for P2-P3 and P1-P4 respectively. These findings suggest the passive exoskeleton evaluated in this study attenuates the shoulder muscles’ effort during static work-related tasks, with implications on the prevention of musculoskeletal disorders

    Effects of Natural and Anthropogenic Stressors on Fucalean Brown Seaweeds Across Different Spatial Scales in the Mediterranean Sea

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    Algal habitat-forming forests composed of fucalean brown seaweeds (Cystoseira, Ericaria, and Gongolaria) have severely declined along the Mediterranean coasts, endangering the maintenance of essential ecosystem services. Numerous factors determine the loss of these assemblages and operate at different spatial scales, which must be identified to plan conservation and restoration actions. To explore the critical stressors (natural and anthropogenic) that may cause habitat degradation, we investigated (a) the patterns of variability of fucalean forests in percentage cover (abundance) at three spatial scales (location, forest, transect) by visual estimates and or photographic sampling to identify relevant spatial scales of variation, (b) the correlation between semi-quantitative anthropogenic stressors, individually or cumulatively (MA-LUSI index), including natural stressors (confinement, sea urchin grazing), and percentage cover of functional groups (perennial, semi-perennial) at forest spatial scale. The results showed that impacts from mariculture and urbanization seem to be the main stressors affecting habitat-forming species. In particular, while mariculture, urbanization, and cumulative anthropogenic stress negatively correlated with the percentage cover of perennial fucalean species, the same stressors were positively correlated with the percentage cover of the semi-perennial Cystoseira compressa and C. compressa subsp. pustulata. Our results indicate that human impacts can determine spatial patterns in these fragmented and heterogeneous marine habitats, thus stressing the need of carefully considering scale-dependent ecological processes to support conservation and restoration

    The ergo-UAS system and a new design approach: Overview and validation

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    Musculoskeletal disorders are the second largest contributor to disability worldwide affecting people across the life-course. Risk identification and design of interventions to reduce the rates of work-related musculoskeletal disorders need to be based on valid and reproducible methods. The Ergo-MTM model is a method used for balancing and design purposes based on the definition of standard time that considers at the same time two of the most important issues in the definition of a fair load. The innovative aspect, is the definition of the Ergonomic Factor determined for every workplace accordingly to the biomechanical load coming from the combination of the assigned operations and quantified with EAWS method. The concept is based on recent relevant standards related to the biomechanical load, which is influenced by the sequence, the repetitiveness and frequency of the operations, in addition to the characteristics of every movement. In the paper the methodology of the project of validation through longitudinal epidemiological study of the EAWS system for the assessment and prevention of biomechanical overload will be presented. Fondazione Ergo and University of Bologna are carrying out the study with the scientific contribution of a panel of experts from academic and non-academic institutions and the Bioethics Committee of the University of Bologna

    Improving scalability of an hybrid infrastructure for e-science applications

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    The Italian GPS receiver for Radio Occultation has been launched from the Satish Dhawan Space Center (Sriharikota, India) on board of the Indian Remote Sensing OCEANSAT-2 satellite. The Italian Space Agency has established a set of Italian universities and research centers to develop an innovative solution in order to quickly elaborate RO data and extract atmospherical profiles. The algorithms adopted can be used to characterize the temperature, pressure and humidity. In consideration of large amount of data to process, an hybrid infrastructure has been created using both the existing grid environment (fully physical) and the virtual environment composed of virtual machines from local cloud infrastructure and Amazon EC2. This enhancement of the project stems from the need of computational power in case of an unexpected burst of calculation that the physical infrastructure would not be able to respond on its own. The virtual environment implemented guarantees flexibility and a progressive scalability and other benefits derived by virtualization and cloud computing. © 2013 Springer-Verlag Berlin Heidelberg

    Coralligenous assemblages differ between limestone and granite: A case study at the Tavolara-Punta Coda Cavallo Marine Protected Area (NE Sardinia, Mediterranean Sea)

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    The Tavolara-Punta Coda Cavallo Marine Protected Area (North-eastern Sardinia, western Mediterranean Sea) includes, in a restricted area, substrates of different lithology. In fact, the Tavolara Island is characterized by limestone (high carbonate content), while the nearby Molara Island and the Molarotto islet are granitic (high quartz content). These peculiar features create a suitable condition to test the hypothesis that the taxonomic richness of the Mediterranean coralligenous communities could be alsodriven by the lithological characteristics of the substrate. Differences, in terms of recurrences of the macrobenthic sessile species, mainly macroalgae, sponges, anthozoans and bryozoans, of the coralligenous communities settled on limestone and granite, were investigated by image analysis. 240 photos on standard surfaces and four video transects were taken in 12 sites at comparable depth (40\u201350 m) but characterized by a different lithology. Multivariate analyses highlighted significant differences among sites, characterized by carbonate and granitic substrates. In general, limestone proved to be more suitable for the development of a thick differentiated coralligenous basal layer and showed a marked heterogeneity. Among structuring species, the gorgonian Eunicella cavolini was more recurrent on limestone than on granite, while the sponges Sarcotragus foetidus, Axinella polypoides and Axinella spp. were significantly more abundant on granite. Results suggest that a number of mechanisms could be involved to explain the observed patterns, such as a selective capacity of several sessile organisms, towards substrate, with ultimate repercussions on the structure of the whole coralligenous assemblage

    Distribution and characterization of deep rhodolith beds off the campania coast (SW Italy, mediterranean sea)

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    Rhodolith beds (RBs) are bioconstructions characterized by coralline algae, which provide habitat for several associated species. Mediterranean RBs are usually located in the mesophotic zone (below 40 m), and thus are frequently remote and unexplored. Recently, the importance and vulnerability of these habitats have been recognized by the European Community and more attention has been drawn to their investigation and conservation. This study reports the results of an extensive monitoring program, carried out within the Marine Strategy Framework Directive (2008/56/EC), in six sites off the Campania coast (Italy, Mediterranean Sea). New insights were given into the distribution, cover, vitality (i.e., live/dead rhodolith ratio), structural complexity, and coralline algae composition of RBs. Remotely operated vehicles (ROV) investigations allowed the description of several RBs, and the discovery of a RB with rhodolith cover >65% offshore the Capri Island. Only two sites (Secchitiello and Punta Campanella) showed a very low mean cover of live rhodoliths (<10%); hence, not being classifiable as RBs. The collected rhodoliths were mostly small pralines (~2 cm), spheroidal to ellipsoidal, with growth-forms ranging from encrusting/warty to fruticose/lumpy. Coralline algae identification revealed a high diversity within each bed, with a total of 13 identified taxa. The genus Lithothamnion dominated all sites, and Phymatolithon calcareum and Lithothamnion corallioides, protected by the Habitats Directive (92/43/EEC), were detected in all RBs
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