Analysis of wheelchair sprint biomechanics on two elite athletes on an instrumented drum ergometer

Introduction. Wheelchair athletics requires the maximization of pushing technique throughout the full length of the race, with particular attention to the transition from start to full speed. The use of dynamometric handrims, introduced for complete propulsion analysis has only recently made available with lightweight portable solutions for athletics [1]. Drum ergometers have also showed to be effective for the study several disciplines in the analysis of propulsion techniques [2]. The use of force plates under the wheels only accounts for the first start push; the use of IMU can instead follow the action along the full race in both simulated or track measurements [3]. In the present work, the combination of a validated drum ergometer, IMU sensors and EMG analysis was adopted to study and compare the sprint biomechanics of two elite athletes on a simulated 100m sprint. Methods. A drum ergometer [2] was adapted to host the athletics wheelchairs restrained at the front wheels. Inertial disks were applied to the drums to match the equivalent linear inertia of each subject (Figure 1.a). A set of Inertial sensors was placed on the hands and wheels of the athletes. Eight EMG sensors were placed on trapezius descendens (TD) right, deltoideus anterior (DA) right, latissimus dorsi (LD) right, pectoralis major (PM) right, biceps brachii (BB) left & right and triceps brachii (TB) left & right. IMU and EMG were captured with a MuscleLab system from Ergomotion. Two elite wheelchair athletes of Italian National Team, D.G. (T 53, 77kg, 100m P.B. 15.92s) and G.S. (T54, 56kg, 100m P.B. 14.93s) volunteered for the study and performed 5 repetitions of a simulated 100m sprint. As previous researchers, two events related to hand-to-rim contact were evaluated using hand acceleration profiles: Hand contact (HC) and Hand Release (HR). As a result, the Push Phase (PP), and the Recovery Phase (RP), were calculated, together with the Total Push Angle (TPA). Similarly to other experiences [4], athletes were asked to perform static maximal voluntary pushes against the blocked drum resistance at three hand positions on the rim: HC, HR and an intermediate position. Isometric tangential push forces at the rim were calculated from the peak torque recorded at the drum and normalized to body weight BW as in Figure 1.b. EMG moving 50 ms window RMS signals were normalized to the trial maximum value: a threshold of 20% was chosen to consider the muscle activation pattern in a polar graph as in Figure 1.c. Results. Simulated best sprint time on the drum ergometer resulted 15.25s for D.G. and 14.72s for G.S., very close to their personal best, thus confirming the validity of the equivalent intertial drum ergometer. Highest isometric forces were obtained at the HC position as shown in Figure 1.b. EMG results presented in Figure 1.c showed how the two athletes adopted different pushing techniques at 5th and 25th push. Both athletes shift forward the HC and HR position at higher speed and widen their TPA, but G.S. TPA increase is more evident. Clock polar diagram allow to capture the differences in muscle coordination among athletes and the change of activation from slow to high speed. Discussion. The use of wireless sensors for IMU and EMG analysis allows for the extension of the method to track tests, in combination with the collection of loads from instrumented handrims that are under development

Microendoscopic Surgery of Middle Ear and Petrous Bone: Benefits Analysis

Objectives: Endoscopy has become routinely used in middle ear surgery. The aim of this study is to analyze where this tool may complement the traditional microscopic approach. This is a retrospective study done in single tertiary hospital. Methods: We reviewed 342 middle ear/petrous bone surgical procedures performed between 2005 and 2015. Only cases in which both microscopic and endoscope-assisted techniques were used have been included. Sixty-six patients received this double-technique surgery: 51 (77.2%) had middle ear/mastoid and petrous bone cholesteatomas (46 middle ear and mastoid and 5 acquired/congenital petrous bone cholesteatomas), 5 (7.5%) had glomus tympanicum tumors (GTT), 4 (6%) had an ossicular chain dislocation, 3 (4.5%) had purulent chronic otitis media, 2 (3%) had tympanosclerosis, and 1 (1.5%) had an ossicular chain malformation. Results: The endoscope was helpful to remove disease remnants not accessible by microscope in 41 (62%) of the cases; 37 (90%) were cholesteatomas, 3 (7%) were GTT, and only 1 (3%) was an open tympanosclerosis. In the remaining 25 (37.8%) cases, the endoscope was useful only to visualize the cavity since the microscope had already been successful in removing the entire lesion. Conclusions: The endoscopy can add valuable information and support to the usual microscope approach alone. The consensus of a single best technique does not yet exist, but the physician should choose the best modality or combination of modalities in order to cure the patient and prevent any possible complications or recurrence of the pathology

BioMet®Tools: from modeling and simulation to product design and development

BioMet®Tools is a set of software applications developed for the biometrical characterization of voice in different fields as voice quality evaluation in laryngology, speech therapy and rehabilitation, education of the singing voice, forensic voice analysis in court, emotional detection in voice, secure access to facilities and services, etc. Initially it was conceived as plain research code to estimate the glottal source from voice and obtain the biomechanical parameters of the vocal folds from the spectral density of the estimate. This code grew to what is now the Glottex®Engine package (G®E). Further demands from users in medical and forensic fields instantiated the development of different Graphic User Interfaces (GUI’s) to encapsulate user interaction with the G®E. This required the personalized design of different GUI’s handling the same G®E. In this way development costs and time could be saved. The development model is described in detail leading to commercial production and distribution. Study cases from its application to the field of laryngology and speech therapy are given and discussed

BioMet®Phon: A system to monitor phonation quality in the clinics

BioMet®Phon is a software application developed for the characterization of voice in voice quality evaluation. Initially it was conceived as plain research code to estimate the glottal source from voice and obtain the biomechanical parameters of the vocal folds from the spectral density of the estimate. This code grew to what is now the Glottex®Engine package (G®E). Further demands from users in laryngology and speech therapy fields instantiated the development of a specific Graphic User Interface (GUI’s) to encapsulate user interaction with the G®E. This gave place to BioMet®Phon, an application which extracts the glottal source from voice and offers a complete parameterization of this signal, including distortion, cepstral, spectral, biomechanical, time domain, contact and tremor parameters. The semantic capabilities of biomechanical parameters are discussed. Study cases from its application to the field of laryngology and speech therapy are given and discussed. Validation results in voice pathology detection are also presented. Applications to laryngology, speech therapy, and monitoring neurological deterioration in the elder are proposed

Finding Quantum Critical Points with Neural-Network Quantum States

Finding the precise location of quantum critical points is of particular importance to characterise quantum many-body systems at zero temperature. However, quantum many-body systems are notoriously hard to study because the dimension of their Hilbert space increases exponentially with their size. Recently, machine learning tools known as neural-network quantum states have been shown to effectively and efficiently simulate quantum many-body systems. We present an approach to finding the quantum critical points of the quantum Ising model using neural-network quantum states, analytically constructed innate restricted Boltzmann machines, transfer learning and unsupervised learning. We validate the approach and evaluate its efficiency and effectiveness in comparison with other traditional approaches.Comment: 19 pages, 12 figures, extended version of an accepted paper at the 24th European Conference on Artificial Intelligence (ECAI 2020

The ALLgorithMM: How to define the hemodilution of bone marrow samples in lymphoproliferative diseases

IntroductionMinimal residual disease (MRD) is commonly assessed in bone marrow (BM) aspirate. However, sample quality can impair the MRD measurement, leading to underestimated residual cells and to false negative results. To define a reliable and reproducible method for the assessment of BM hemodilution, several flow cytometry (FC) strategies for hemodilution evaluation have been compared. MethodsFor each BM sample, cells populations with a well-known distribution in BM and peripheral blood - e.g., mast cells (MC), immature (IG) and mature granulocytes (N) - have been studied by FC and quantified alongside the BM differential count. ResultsThe frequencies of cells' populations were correlated to the IG/N ratio, highlighting a mild correlation with MCs and erythroblasts (R=0.25 and R=0.38 respectively, with p-value=0.0006 and 0.0000052), whereas no significant correlation was found with B or T-cells. The mild correlation between IG/N, erythroblasts and MCs supported the combined use of these parameters to evaluate BM hemodilution, hence the optimization of the ALLgorithMM. Once validated, the ALLgorithMM was employed to evaluate the dilution status of BM samples in the context of MRD assessment. Overall, we found that 32% of FC and 52% of Next Generation Sequencing (NGS) analyses were MRD negative in samples resulted hemodiluted (HD) or at least mildly hemodiluted (mHD). ConclusionsThe high frequency of MRD-negative results in both HD and mHD samples implies the presence of possible false negative MRD measurements, impairing the correct assessment of patients' response to therapy and highlighs the importance to evaluate BM hemodilution

Structured reporting for fibrosing lung disease: a model shared by radiologist and pulmonologist

Objectives: To apply the Delphi exercise with iterative involvement of radiologists and pulmonologists with the aim of defining a structured reporting template for high-resolution computed tomography (HRCT) of patients with fibrosing lung disease (FLD). Methods: The writing committee selected the HRCT criteria\ue2\u80\u94the Delphi items\ue2\u80\u94for rating from both radiology panelists (RP) and pulmonology panelists (PP). The Delphi items were first rated by RPs as \ue2\u80\u9cessential\ue2\u80\u9d, \ue2\u80\u9coptional\ue2\u80\u9d, or \ue2\u80\u9cnot relevant\ue2\u80\u9d. The items rated \ue2\u80\u9cessential\ue2\u80\u9d by < 80% of the RP were selected for the PP rating. The format of reporting was rated by both RP and PP. Results: A total of 42 RPs and 12 PPs participated to the survey. In both Delphi round 1 and 2, 10/27 (37.7%) items were rated \ue2\u80\u9cessential\ue2\u80\u9d by more than 80% of RP. The remaining 17/27 (63.3%) items were rated by the PP in round 3, with 2/17 items (11.7%) rated \ue2\u80\u9cessential\ue2\u80\u9d by the PP. PP proposed additional items for conclusion domain, which were rated by RPs in the fourth round. Poor consensus was observed for the format of reporting. Conclusions: This study provides a template for structured report of FLD that features essential items as agreed by expert thoracic radiologists and pulmonologists

Prolonged higher dose methylprednisolone vs. conventional dexamethasone in COVID-19 pneumonia: a randomised controlled trial (MEDEAS)

Dysregulated systemic inflammation is the primary driver of mortality in severe COVID-19 pneumonia. Current guidelines favor a 7-10-day course of any glucocorticoid equivalent to dexamethasone 6 mg·day-1. A comparative RCT with a higher dose and a longer duration of intervention was lacking

High-resolution CT phenotypes in pulmonary sarcoidosis: a multinational Delphi consensus study

One view of sarcoidosis is that the term covers many different diseases. However, no classification framework exists for the future exploration of pathogenetic pathways, genetic or trigger predilections, patterns of lung function impairment, or treatment separations, or for the development of diagnostic algorithms or relevant outcome measures. We aimed to establish agreement on high-resolution CT (HRCT) phenotypic separations in sarcoidosis to anchor future CT research through a multinational two-round Delphi consensus process. Delphi participants included members of the Fleischner Society and the World Association of Sarcoidosis and other Granulomatous Disorders, as well as members' nominees. 146 individuals (98 chest physicians, 48 thoracic radiologists) from 28 countries took part, 144 of whom completed both Delphi rounds. After rating of 35 Delphi statements on a five-point Likert scale, consensus was achieved for 22 (63%) statements. There was 97% agreement on the existence of distinct HRCT phenotypes, with seven HRCT phenotypes that were categorised by participants as non-fibrotic or likely to be fibrotic. The international consensus reached in this Delphi exercise justifies the formulation of a CT classification as a basis for the possible definition of separate diseases. Further refinement of phenotypes with rapidly achievable CT studies is now needed to underpin the development of a formal classification of sarcoidosis