Optimal Design for Vibration Mitigation of a Planar Parallel Mechanism for a Fast Automatic Machine

This work studies a planar parallel mechanism installed on a fast-operating automatic machine. In particular, the mechanism design is optimized to mitigate experimentally-observed vibrations. The latter are a frequent issue in mechanisms operating at high speeds, since they may lead to low-quality products and, ultimately, to permanent damage to the goods that are processed. In order to identify the vibration cause, several possible factors are explored, such as resonance phenomena, elastic deformations of the components, and joint deformations under operation loads. Then, two design optimization are performed, which result in a significant improvement in the vibrational behaviour, with oscillations being strongly reduced in comparison to the initial design

2D Continuous Wavelet Transform of potential fields due to extended source distributions

AbstractWe analyse the real Continuous Wavelet Transform 2D (CWT2D) of potential fields for the investigation of potential field singularities. We focus our attention to extended geological sources, in order to verify the reliability of this method with realistic fields. 3D space-scale representation (3D Scalogram) related to synthetic models were generated, showing the Wavelet Transform Modulus Maxima (WTMM) at each scale. The WTMM are related to the shape of the source, so defining some sort of source boundary analysis through the CWT. Wavelets of different order may help to gain resolution and define source features. Selecting a range of scales where the sources behave as if they are approximately isolated, the depth to the source may be estimated basing on the property that the lines joining the modulus maxima of the wavelet coefficients at different scales (WTMML) intersect each other at the edges of the causative body. Therefore, it is possible to manage the information contained in the wavelet transform of fields related to extended sources. In the real case of the anomaly gravity map of the Vesuvius area (Italy), we estimated the depth of the Mesozoic carbonate basement in the Pompei Basin. We showed also how the WTMML information can be integrated to that of another multiscale method, the Depth from Extreme Points (DEXP) transformation, which is also related to the source density distribution of a given region

enabling access to cultural heritage for the visually impaired an interactive 3d model of a cultural site

Abstract We have developed low cost interactive 3D models that improve access to architectural details of cultural sites for all, including people with vision impairments. Our approach uses rapid prototyping and 3D printing along with a very small single-board computer for automating user interaction. As a case study, we developed a prototype model of "Piazza dei Miracoli" (Pisa, Italy), the famous square where the Leaning Tower is located. The system is a combination of tactile information with audio descriptions to enable potential users to explore the artifact autonomously. We exploited low-cost and partially open-source technologies, thus rendering our system easily replicable. We evaluated the interactive system with a group of eight completely blind and partially sighted users. Our user test confirmed the validity of our approach: (1) the three-dimensional models and the tactile reproduction of details obtained via a low-cost 3D printing solution are well perceived by touch; (2) the semantic aural information activated via perceptible buttons on demand and the different content levels for the audio tracks are suitable for an interactive, autonomous and satisfying exploration

Respicelltm: An innovative dissolution apparatus for inhaled products

To overcome some of the shortfalls of the types of dissolution testing currently used for pulmonary products, a new custom-built dissolution apparatus has been developed. For inhalation products, the main in vitro characterisation required by pharmacopoeias is the deposition of the active pharmaceutical ingredient in an impactor to estimate the dose delivered to the target site, i.e., the lung. Hence, the collection of the respirable dose (<5 µm) also appears to be an essential requirement for the study of the dissolution rate of particles, because it results as being a relevant parameter for the pharmacological action of the powder. In this sense, dissolution studies could become a complementary test to the routine testing of inhaled formulation delivered dose and aerodynamic performance, providing a set of data significant for product quality, efficacy and/or equivalence. In order to achieve the above-mentioned objectives, an innovative dissolution apparatus (RespiCell™) suitable for the dissolution of the respirable fraction of API deposited on the filter of a fast screening impactor (FSI) (but also of the entire formulation if desirable) was designed at the University of Parma and tested. The purpose of the present work was to use the RespiCell dissolution apparatus to compare and discriminate the dissolution behaviour after aerosolisation of various APIs characterised by different physico-chemical properties (hydrophilic/lipophilic) and formulation strategies (excipients, mixing technology)

The cold-water coral province of the eastern Ligurian Sea (NW Mediterranean Sea): historical and novel evidences

Several bathyal cold-water coral provinces, characterized by a lush growth of habitat-forming scleractinians, have been recognized in the Mediterranean Sea. However, the search for this biogenic habitat only marginally targeted the Italian coast of the Ligurian Sea (NW Mediterranean basin) despite historical and a few recent local studies in the region reporting the presence of corals. This study used bathymetry maps, side-scan sonar profiles, historical charts, and trawling routes to identify sites that could potentially host coral habitats in the eastern sector of the Ligurian Sea. Remotely operated vehicle video footage from various projects (2015-2021, 20 dives) was then used to characterize four sub-areas (Genoa Plateau, Portofino, Deiva Marina, and Monterosso) where corals were detected between 450 m and 750 m depth. Radiocarbon dating was used to trace back the geological history of the coral structures. A small coral mound, impacted by trawling activities, was found on the Genoa Plateau, while four massive coral structures were found in the other sub-areas, mainly located in a morphologically complex and highly energetic canyon region. High levels of megafaunal biodiversity, including rarely reported alcyonaceans as Placogorgia coronata, were observed together with moderate fishing impact. Overall, the identified coral areas potentially account for 9 km(2) of both subfossil mounds (as old as 13300 years BP), dominated by Desmophyllum pertusum, and living reefs, dominated by Madrepora oculata, the latter representing up to 23% of the substrate coverage. The few living colonies of D. pertusum in the area represent the first documented records for the Ligurian Sea. These data support the presence of a distinct eastern Ligurian cold-water coral province

An earth pole-sitter using hybrid propulsion

In this paper we investigate optimal pole-sitter orbits using hybrid solar sail and solar electric propulsion (SEP). A pole-sitter is a spacecraft that is constantly above one of the Earth's poles, by means of a continuous thrust. Optimal orbits, that minimize propellant mass consumption, are found both through a shape-based approach, and solving an optimal control problem, using a direct method based on pseudo-spectral techniques. Both the pure SEP case and the hybrid case are investigated and compared. It is found that the hybrid spacecraft allows consistent savings on propellant mass fraction. Finally, is it shown that for sufficiently long missions (more than 8 years), a hybrid spacecraft, based on mid-term technology, enables a consistent reduction in the launch mass for a given payload, with respect to a pure SEP spacecraft

Management of cutaneous discomfort in patients with scleroderma: a clinical trial.

Systemic sclerosis (scleroderma) is a disease of unknown cause, the hallmark of which is induration of the skin. This bad condition of the skin influences negatively the quality of life of patients with scleroderma. The aim of the study was to verify the efficacy of two formulations, specifically designed to wash, moisturize and soothe the scleroderma skin. An independent, randomized, double blind, controlled trial was conducted in the Department of Rheumatology of "A. Galateo" Hospital in San Cesario di Lecce. Forty-six women affected by scleroderma, and treated with Iloprost every month, were divided into two groups: group 1 followed a specific treatment with cleansing formulation only, group 2 followed a combined treatment with the cleansing solution and the moisturizing solution. In addition, a third group was evaluated: 14 women, who did not undergo intravenous Iloprost therapy, were treated simultaneously with the cleansing formulation and the moisturizing formulation. The three treatments lasted for 4 weeks. Reduction in trans epidermal water loss (TEWL), increase in moisturization of the stratum corneum, reduction in Skin Score and improvement in quality of life were assessed. Very significant improvement in quality of life occurred in each group. Group 2 obtained very significant improvement in hydration and reduction in skin score and TEWL. The study showed that the daily use of both formulations proved to be effective in washing, hydrating and soothing the skin of patients with scleroderma, especially in association with Iloprost therapy

The paleo-community of the Sciacca red coral

The sub-fossil red coral deposits of Sciacca (Sicily Channel) have attracted scientific attention for nearly 150 years. Their origin and formation have been long questioned and investigated, given the fact that they represent one of the most intriguing geobiological events ever to occur in the Mediterranean basin. Less attention was given to the paleo-community associated with the sub-fossil coral. Radiocarbon age determinations, in particular, were provided only for red coral, neglecting the possibility of understanding which species were simultaneously present in the coralline paleo-community and which was their role. The study of cemented coral rubble pieces revealed that Corallium rubrum covered the largest time interval (more than 3000 years) and was contemporary to many secondary epibionts over two millennia and to Madrepora oculata for about 500 years; this last finding suggested that an uncommon co-dominance between the two structuring species occurred in the nearby living communities. The lack of Fe-Mg deposits on the cemented coral rubbles coupled with the low bioerosion rate of the red coral skeletons by the demosponge Siphonodictyon coralliirubri (assessed through the analysis of the erosive paleo-scars) suggested that the deposits met with a rapid sediment cover-up. Moreover, for the first time, the analysis of a piece of cemented coral rubble of sub-fossil red coral coming from Sardinian waters confirmed that, albeit to a lesser extent, the conditions favouring the preservation of dead corals can occur also in different localities far from Sciacca

The sub-fossil red coral of Sciacca (Sicily Channel, Mediterranean Sea): colony size and age estimates

The Mediterranean red coral, Corallium rubrum (L.), has been a valuable economic resource for more than 2000 years. The Sicily Channel and surrounding areas are one of the most famous red coral fishing grounds of the whole region, hosting the deepest ever found living colonies and large sub-fossil red coral deposits; the so-called Sciacca banks are a unique location in the whole Mediterranean Sea. In this paper, a morphometric description of this sub-fossil population is presented for the first time from studies of colonies in the collection of several coral factories from Torre del Greco (Naples), with radiocarbon age estimations and growth rate evaluations. From the results of this study, after several thousand years Sciacca red coral colonies maintained the organic matrix structure with evident annual discontinuities, allowing estimations of the annual growth rate (about 0.3 mm/year) and the average population age (about 33.5 years). These resulting data are similar to the values determined for deep-dwelling living red coral populations. The radiocarbon dating evidenced a range of ages, from 8300 to 40 years before 1950 CE, mostly falling between 2700 and 3900 YBP, suggesting that colonies accumulated over a wide span of time. In view of the tectonically active nature of the area, several catastrophic events affected these ancient populations, maintaining them in a persistent state of early-stage, structurally similar to the those in current over-exploited areas

Association between Mediterranean lifestyle and perception of well-being and distress in a sample population of university Italian students

We investigated the extent to which adherence to the Mediterranean diet (MD) in combination with Mediterranean lifestyle factors influenced students’ perceptions of subjective well-being (SWB) and distress. 939 undergraduates completed a survey to assess sociodemographic and lifestyle characteristics, including adherence to the MD, depression, anxiety, stress, and SWB. Data were analysed with correlation, logistic, and multiple linear regression models. Higher adherence to MD correlated with better SWB. Fruit, red meat, sweet and caffeinated beverages contributed significantly. However, it was the combination of adherence to MD with other factors, including quality of social relationships, income, smoking, sleep, and physical activity that better predicted SWB. Our results confirm the positive influence of MD on SWB. However, they also suggest the need to consider perceptions of well-being by a more holistic approach that considers physical and social factors simultaneously to improve the development of more effective educational and motivational programmes.info:eu-repo/semantics/publishedVersio