Publications by authors named "Pier Paolo Valentini"

Surface electromyography techniques are widely used in field of motion analysis and ergonomics combining precise muscular activation assessment with low-invasiveness and wearability. The aim of this investigation is to identify the myoelectrical manifestations of fatigue and to compare the effectiveness of sEMG-based quantitative indices for fatigue assessment. The investigated indexes are the ARV and RMS signal amplitudes, the mean frequency, the median frequency, the Dimitrov index, the instantaneous mean frequency and Wavelet distribution-based 51 index.

View Article and Find Full Text PDF

Objective: We propose a procedure for calibrating 4 parameters governing the mechanical boundary conditions (BCs) of a thoracic aorta (TA) model derived from one patient with ascending aortic aneurysm. The BCs reproduce the visco-elastic structural support provided by the soft tissue and the spine and allow for the inclusion of the heart motion effect.

Methods: We first segment the TA from magnetic resonance imaging (MRI) angiography and derive the heart motion by tracking the aortic annulus from cine-MRI.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the prediction of ascending aortic aneurysm growth using local and global shape features.
  • It includes 70 patients with aneurysms, analyzing 3D data to compute various shape features and develop regression models for growth prediction.
  • Results indicate that global shape features, particularly from PLS analysis, significantly enhance prediction accuracy, revealing that larger aneurysms near the heart tend to grow faster.
View Article and Find Full Text PDF

The current guidelines for the ascending aortic aneurysm (AsAA) treatment recommend surgery mainly according to the maximum diameter assessment. This criterion has already proven to be often inefficient in identifying patients at high risk of aneurysm growth and rupture. In this study, we propose a method to compute a set of local shape features that, in addition to the maximum diameter , are intended to improve the classification performances for the ascending aortic aneurysm growth risk assessment.

View Article and Find Full Text PDF

Several approaches have been used to devise a model of the human tibiofemoral joint for embedment in lower limb musculoskeletal models. However, no study has considered the use of cadaveric 6 × 6 compliance (or stiffness) matrices to model the tibiofemoral joint under normal or pathological conditions. The aim of this paper is to present a method to determine the compliance matrix of an ex vivo tibiofemoral joint for any given equilibrium pose.

View Article and Find Full Text PDF

The paper deals with the comparison between a high-end marker-based acquisition system and a low-cost marker-less methodology for the assessment of the human posture during working tasks. The low-cost methodology is based on the use of a single Microsoft Kinect V1 device. The high-end acquisition system is the BTS SMART that requires the use of reflective markers to be placed on the subject's body.

View Article and Find Full Text PDF

Introduction: Complications and challenges arising from the intraoperative double-stapling technique are seldom reported in colorectal surgery literature. Partial or full-thickness rectal injuries can occur during the introduction and the advancement of the circular stapler along the upper rectum. The aim of this study is to address some of these issues by designing and optimizing a "phantom" anvil manufactured to overcome difficulties throughout the rectal introduction and advancement of the circular stapler for the treatment of benign and malignant colon disease.

View Article and Find Full Text PDF

Purpose: The purpose of this in vitro study was to compare the dimensional accuracy of the pickup impression technique using a modular individual tray (MIT) and using a standard individual tray (ST) for multiple internal-connection implants. The roles of both materials and geometric misfits were considered.

Materials And Methods: First, because the MIT relies on the stiffness and elasticity of acrylic resin material, a preliminary investigation of the resin volume contraction during curing and polymerization was done.

View Article and Find Full Text PDF