3,200 research outputs found
Waterborne GPR survey for estimating bottom-sediment variability: A survey on the Po River, Turin, Italy
We conducted an integrated geophysical survey on a stretch of the river Po in order to check the GPR ability to discriminate the variability of riverbed sediments through an analysis of the bottom reflection amplitudes. We conducted continuous profiles with a 200-MHzGPR system and a handheld broadband EM sensor.Aconductivity meter and a TDR provided punctual measurements of water conductivity, permittivity, and temperature. The processing and interpretation of the GEM-2 and GPR data were enhanced by reciprocal results and by integration with the punctual measurements of the EM properties of the water. We used a processing flow that improved the radargram images and preserved the amplitude ratios among the different profiles and the frequency content at the bottom reflection signal.We derived the water attenuation coefficient both from the punctual measurements using the Maxwell formulas and from the interpretation of the GPR data, finding an optimal matching between the two values. The GPR measurements provided maps of the bathymetry and of the bottom reflection amplitude. The high reflectivity of the riverbed, derived from the GPR interpretation, agreed with the results of the direct sampling campaign that followed the geophysical survey. The variability of the bottom-reflection-amplitudes map, which was not confirmed by the direct sampling, could also have been caused by scattering phenomena due to the riverbed clasts which are dimensionally comparable to the wavelength of the radar pulse
Influence of convex and concave curvatures in a coastal dike line on wave run-up
Due to climatic change and the increased usage of coastal areas, there is an increasing risk of dike failures along the coasts worldwide. Wave run-up plays a key role in the planning and design of a coastal structure. Coastal engineers use empirical equations for the determination of wave run-up. These formulae generally include the influence of various hydraulic, geometrical and structural parameters, but neglect the effect of the curvature of coastal dikes on wave run-up and overtopping. The scope of this research is to find the effects of the dike curvature on wave run-up for regular wave attack by employing numerical model studies for various dike-opening angles and comparing it with physical model test results. A numerical simulation is carried out using DualSPHysics, a mesh-less model and OpenFOAM, a mesh-based model. A new influence factor is introduced to determine the influence of curvature along a dike line. For convexly curved dikes (ad = 210° to 270°) under perpendicular wave attack, a higher wave run-up was observed for larger opening angles at the center of curvature whereas for concavely curved dikes (ad = 90° to 150°) under perpendicular wave attack, wave run-up increases at the center of curvature as the opening angle decreases. This research aims to contribute a more precise analysis and understanding the influence of the curvature in a dike line and thus ensuring a higher level of protection in the future development of coastal structures.Peer ReviewedPostprint (published version
The effects of sars-cov-2 pandemic countermeasures on patients receiving infiltrative treatment for musculoskeletal disorders: A study from an italian cohort
SUMMARY Background. COVID-19 outbreak had a massive worldwide impact and several countermeasures to contain its spread have been adopted, such as the interruption of non-urgent outpatient clinics. We wanted to describe the effects of the national lock-down on the well-being of a cohort of Italian patients with musculoskeletal disorders receiving infiltrative treatment. Methods. 40 patients who received intra-or peri-articular treatment were surveyed using a structuralised questionnaire that assessed their well-being during the first national lockdown. Results. 24 out of 40 patients (60%) did not come back after the re-opening of the Clinic because they were afraid of the pandemic. Of these 24 patients, the 83.3% noticed increased pain and stiffness in the joint. Due to the lockdown, the patient’s quality of life was reduced by 61.66 ± 15.72%. After the lockdown, for the 92% of patients, the infiltrative treatment was perceived as more important than before, the 83% of patients perceived long-term security of infiltrative therapy availability as very important, and the 72% of the patients perceived the lockdown as inadequate. Conclusions. The infiltrative outpatient clinic’s interruption was seen to significant-ly worsen the physical condition of subjects with musculoskeletal disorders, with an important increase in both articular pain and stiffness. Therefore, any kind of infiltra-tive treatment suspension or delay should be avoided
Achilles Tendon Rupture: Mechanisms of Injury, Principles of Rehabilitation and Return to Play
The Achilles tendon is the thickest, strongest and largest tendon in the human body, but despite its size and tensile strength, it frequently gets injured. Achilles tendon ruptures (ATRs) mainly occur during sports activities, and their incidence has increased over the last few decades. Achilles tendon tears necessitate a prolonged recovery time, sometimes leaving long-term functional limitations. Treatment options include conservative treatment and surgical repair. There is no consensus on which is the best treatment for ATRs, and their management is still controversial. Limited scientific evidence is available for optimized rehabilitation regimen and on the course of recovery after ATRs. Furthermore, there are no universally accepted outcomes regarding the return to play (RTP) process. Therefore, the aim of this narrative review is to give an insight into the mechanism of injuries of an ATR, related principles of rehabilitation, and RTP
Assessment, pharmacological therapy and rehabilitation management of musculoskeletal pain in children with mucopolysaccharidoses: a scoping review
Pain of musculoskeletal origin is very common in young patients affected by Mucopolysaccharidoses. This scoping review evaluates the evidence for assessment, pharmacological treatment and rehabilitation management for musculoskeletal pain of the latter
Multilevel Modelling with Spatial Effects
In multilevel modelling, interest in modeling the nested structure of hierarchical data has been accompanied by increasing attention to different forms of spatial interactions across different levels of the hierarchy. Neglecting such interactions is likely to create problems of inference, which typically assumes independence. In this paper we review approaches to multilevel modelling with spatial effects, and attempt to connect the two literatures, discussing the advantages and limitations of various approaches
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