Temporal Asynchrony but Not Total Energy Nor Duration Improves the Judgment of Numerosity in Electrotactile Stimulation

Stroke patients suffer from impairments of both motor and somatosensory functions. The functional recovery of upper extremities is one of the primary goals of rehabilitation programs. Additional somatosensory deficits limit sensorimotor function and significantly affect its recovery after the neuromotor injury. Sensory substitution systems, providing tactile feedback, might facilitate manipulation capability, and improve patient's dexterity during grasping movements. As a first step toward this aim, we evaluated the ability of healthy subjects in exploiting electrotactile feedback on the shoulder to determine the number of perceived stimuli in numerosity judgment tasks. During the experiment, we compared four different stimulation patterns (two simultaneous: short and long, intermittent and sequential) differing in total duration, total energy, or temporal synchrony. The experiment confirmed that the subject ability to enumerate electrotactile stimuli decreased with increasing the number of active electrodes. Furthermore, we found that, in electrotactile stimulation, the temporal coding schemes, and not total energy or duration modulated the accuracy in numerosity judgment. More precisely, the sequential condition resulted in significantly better numerosity discrimination than intermittent and simultaneous stimulation. These findings, together with the fact that the shoulder appeared to be a feasible stimulation site to communicate tactile information via electrotactile feedback, can serve as a guide to deliver tactile feedback to proximal areas in stroke survivors who lack sensory integrity in distal areas of their affected arm, but retain motor skills

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF ASYMMETRICAL BEHAVIOUR OF RUDDER / PROPELLER FOR TWIN SCREW SHIPS

the present work addresses the asymmetrical functioning of rudder/propeller complex of twin screw/twin rudders ships. A series of free running model test results are analysed, with the aid of some simplified numerical calculations. this analysis allows to show the asymmetrical propeller loading during manoeuvres and the considerably different rudder functioning. A possible simplified model to include these effects in manoeuvring simulators is proposed and discussed, allowing to define the needs for future research activities to further improve the understanding of the different phenomena shown

AN ANGULAR RESOLVED ELECTRON-ENERGY-LOSS INVESTIGATION OF HIGHLY ORIENTED PYROLITIC GRAPHITE ELECTRONIC-STRUCTURE RID G-7348-2011

Angular resolved electron energy loss measurements on highly oriented pyrolitic graphite have been performed in reflection kinematics and at grazing incidence angles. Because of the selected kinematics it has been possible to change, almost independently, either the momentum transfer parallel to the surface (q(parallel-to)) or the angle between the momentum transfer and the graphite c axis (q^c). The present measurements have proved to be very sensitive to the surface structure of the sample and have allowed the assignment of the prominent loss at about 6 eV to a pi --> pi* excitation mainly localized perpendicular to the c axis. Possible contributions from surface localized states have also been detected. This transition shows negligible dispersion in q(parallel-to) and its energy centroid appears to be shifted with respect to previous surface and bulk measurements. Furthermore, the measured cross-sections are brought to the same relative scale for each grazing angle, and the loss and scattering functions are derived from data taken in reflection kinematics. The relevance of the kinematic prefactor in deriving transition energies from loss spectra is discussed with an emphasis on the role of q(parallel-to) zeroes

Numerical Analysis of the Ship Propulsion Control System Effect on Manoeuvring Characteristics in Model and Full scale

A comprehensive approach to simulate the interaction between the ship propulsion system and manoeuvrability, during transients and off design conditions, is presented. The increasing attention on the manoeuvring features of the vessel has forced designers to consider this aspect already in the preliminary stages of the project. Data about manoeuvring characteristics may be obtained by means of several model tests (at planar motion mechanism or with free running models). However, differences between model tests and full scale trials exist. From the hydrodynamic point of view, some disagreements are due to the scale effects but also the effect of the propulsion control system, highly non-linear, may provide a considerable contribution to such differences. These dynamical aspects cannot be taken into account with traditional methodologies and purely stationary approaches. For these reasons, the ship dynamic behaviour is evaluated by time domain simulators, developed by the authors, which include the ship dynamics, the propulsion plant dynamics and the propulsion control system logics. At the end of the paper some simulation results are shown in order to better understand the effects and the differences of the propulsion control settings on the ship manoeuvrability in model and full scale

Experimental and Numerical Investigation of Asymmetrical Behaviour of Rudder / Propeller for Twin Screw Ships

THE PRESENT WORK ADDRESSES THE ASYMMETRICAL FUNCTIONING OF RUDDER/PROPEL LER COMPLEX OF TWIN SCREW/TWIN RUDDERS SHIPS. A SERIES OF FREE RUNNING MODEL TEST RESULTS ARE ANALYSED, WITH THE AID OF SOME SIMPLIFIED NUMERICAL CALCULATIONS. THIS ANALYSIS ALLOWS TO SHOW THE ASYMMETRICAL PROPEL LER LOADING DURING MANOEUVRES AND THE CONSIDERABLY DI FFERENT RUDDER FUNCTIONING. A POSSIBLE SIMPLIFIED MODEL TO INCLUDE THESE EFFECTS IN MANOEUVRING SIMULATORS IS PROPOSED AND DISCUSSED, ALLOWING TO DEFINE THE NEEDS FOR FUTURE RESEARCH ACTIVITIES TO FURTHER IMPROVE THE UNDERSTANDING OF THE DIFFERENT PHENOMENA SHOWN

Extra-auditory effects of noise exposure in school workers and preventive measures. A systematic review

OBJECTIVE: Noise is still today one of the main causes of occupational diseas- es; in fact, in Italy in the three-year period 2019- 2022, hearing loss represented 15% of all occu- pational diseases recognized by the National Institute for Insurance against Accidents at Work. The extra-auditory effects related to noise expo- sure also require particular attention, because they can interfere with mental activities that re- quire concentration, memory and ability to deal with complex problems, causing sleep and learn- ing disorders. For this reason, acoustic comfort is considered a fundamental requirement for ob- taining an optimal degree of well-being in closed environments. In schools, a high degree of noise pollution not only makes it difficult for students to listen and learn, but also affects school workers. The aim of this study was to perform a systemat- ic review of international literature and analysis of the preventive measures of extra-auditory effects among school workers. MATERIALS AND METHODS: The presenta- tion of this systematic review is in accordance with the PRISMA statement. The methodologi- cal quality of the selected studies was assessed with specific rating tools (INSA, Newcastle Otta- wa Scale, JADAD, JBI scale and AMSTAR). On- ly publications in English were selected. No re- strictions were applied for the publication type. We excluded articles not concerned with the ex- tra-auditory effects of noise exposure in school workers and preventive measures, findings of less academic significance, editorial articles, in- dividual contributions, and purely descriptive studies published in scientific conferences. RESULTS: Online research indicated 4,363 references: PubMed (2,319), Scopus (1,615) and Cochrane Library (429) have been consulted; 30 studies were included in this review (5 narrative or systematic reviews and 25 original articles). Regarding the scores of narrative reviews, the INSA score showed an average and a median value of 6.5, thus indicating an intermediate/high quality of the studies. Regarding the scores of systematic reviews, the AMSTAR score showed an average of 6.7 and a median and a modal val- ue of 6, thus indicating a high quality of the stud- ies. The scores assigned to the original articles have an average and median value of 7 and a modal value of 6 and this demonstrates an inter- mediate/high quality of the studies. CONCLUSIONS: We can assume that, as it is highlighted by this study, to date these con- sequences are not considered at the legisla- tive level for the protection of exposed workers. The extra-auditory effects impacting health af- terward environmental noise exposure are ma- ny and widespread. Therefore, there is a need for interventions to be carried out by institutions and that the physician of the schools, during health surveillance, investigates the effects and clinical manifestations, in order to prevent disor- ders and deficits highlighted by our study

Extra-auditory effects of noise exposure in school workers and preventive measures: a systematic review

OBJECTIVE: Noise is still today one of the main causes of occupational diseases; in fact, in Italy in the three-year period 2019-2022, hearing loss represented 15% of all occupational diseases recognized by the National Institute for Insurance against Accidents at Work. The extra-auditory effects related to noise exposure also require particular attention, because they can interfere with mental activities that require concentration, memory and ability to deal with complex problems, causing sleep and learning disorders. For this reason, acoustic comfort is considered a fundamental requirement for obtaining an optimal degree of well-being in closed environments. In schools, a high degree of noise pollution not only makes it difficult for students to listen and learn, but also affects school workers. The aim of this study was to perform a systematic review of international literature and analysis of the preventive measures of extra-auditory effects among school workers. MATERIALS AND METHODS: The presentation of this systematic review is in accordance with the PRISMA statement. The methodological quality of the selected studies was assessed with specific rating tools (INSA, Newcastle Ottawa Scale, JADAD, JBI scale and AMSTAR). Only publications in English were selected. No restrictions were applied for the publication type. We excluded articles not concerned with the extra-auditory effects of noise exposure in school workers and preventive measures, findings of less academic significance, editorial articles, individual contributions, and purely descriptive studies published in scientific conferences. RESULTS: Online research indicated 4,363 references: PubMed (2,319), Scopus (1,615) and Cochrane Library (429) have been consulted; 30 studies were included in this review (5 narrative or systematic reviews and 25 original articles). Regarding the scores of narrative reviews, the INSA score showed an average and a median value of 6.5, thus indicating an intermediate/high quality of the studies. Regarding the scores of systematic reviews, the AMSTAR score showed an average of 6.7 and a median and a modal value of 6, thus indicating a high quality of the studies. The scores assigned to the original articles have an average and median value of 7 and a modal value of 6 and this demonstrates an intermediate/high quality of the studies. CONCLUSIONS: We can assume that, as it is highlighted by this study, to date these consequences are not considered at the legislative level for the protection of exposed workers. The extra-auditory effects impacting health afterward environmental noise exposure are many and widespread. Therefore, there is a need for interventions to be carried out by institutions and that the physician of the schools, during health surveillance, investigates the effects and clinical manifestations, in order to prevent disorders and deficits highlighted by our study

La valutazione dei rischi lavorativi: criticità ed indicazioni operative

La procedura di Valutazione dei Rischi è fondamentale per la tutela dei lavoratori (art. 15 D.Lgs. 81/08 s.m.i.) e trova la sua applicazione operativa nell'elaborazione del documento di valutazione dei rischi. La redazione di tale documento, un obbligo del Datore di Lavoro, che può avvalersi a tal fine di vari professionisti ed a cui deve collaborare il Medico Competente, non può essere considerata un mero obbligo legislativo, ma una fotografia reale e continuamente dinamica dei rischi lavorativi e delle misure di prevenzione-protezione atte a ridurli. L'inevitabile complessità dell'argomento, oltre alla rapida evoluzione delle conoscenze scientifiche e delle disposizioni normative, determina svariate difficoltà nell'applicazione corretta della procedura, che richiede competenze specialistiche e multidisciplinari. Nell'ambito della Società Italiana di Igiene (SItI) il Gruppo di Lavoro 'Igiene del Lavoro' ha intrapreso la stesura di un volume che affronta le criticità che possono emergere nel processo di valutazione dei rischi e nella successiva stesura del DVR, anche indicando possibili azioni migliorative che contribuiscano a garantire la qualità e la completezza del processo. Il volume ha un carattere multidisciplinare e specialistico in quanto la sua redazione è stata curata da numerosi esperti di diverse discipline, mantenendo comunque una visione unitaria dell'approccio metodologico, basato sui fondamenti dell'analisi del rischio. Il testo si articola in due parti: nella prima sono descritti gli aspetti generali che caratterizzano il processo, con particolare riferimento all'inquadramento normativo, alla formazione necessaria a ciascuna figura coinvolta nella prevenzione dei rischi in ambiente lavorativo e alle metodologie e alle criticità da considerare nella valutazione di ciascuno dei rischi indicati nella normativa vigente. Nell'ambito di questo ultimo aspetto, particolare attenzione è stata rivolta ai rischi trasversali; sono stati, infatti, affrontati in maniera specifica tematiche quali la comunicazione dei rischi, la valutazione di questi in ottica di genere e l'influenza che stili di vita e abitudini voluttuarie possono esercitare in ambiente di lavoro. In questa prima parte del volume sono inoltre illustrate le caratteristiche fondamentali e le indicazioni all'applicazione degli approcci probabilistici o degli algoritmi nella valutazione dei rischi. Nella seconda parte del volume sono descritte le principali categorie di rischi da valutare in ambiente di lavoro (fisici, chimici, biologici, ergonomici, infortunistici e psico-sociali) considerando le criticità che possono emergere nel processo di valutazione ed indicando possibili soluzioni applicative, anche attraverso indicazioni sintetiche e schematiche quali le check list operative. Riguardo alla valutazione dei rischi di natura biologica e chimica sono riportati due esempi applicativi: la tubercolosi nelle strutture sanitarie ed il comparto rifiuti per i primi, la produzione e l'uso di nanomateriali per i secondi. Il volume può essere, pertanto, considerato un utile strumento di supporto sia per i professionisti direttamente coinvolti nel processo di valutazione dei rischi in ambiente di lavoro, sia per coloro che si avvicinano a tale tematica ed è un manuale operativo da utilizzare sul campo. La multidisciplinarità del testo è espressione della principale caratteristica della vocazione igienista che presenta sempre una visione globale e integrata delle tematiche trattate

Extra-Auditory Effects from Noise Exposure in Schools: Results of Nine Italian Case Studies

Noise exposure may cause auditory and extra-auditory effects. School teachers and students are exposed to high noise levels which have an impact on perceptual-cognitive and neurobehavioral aspects. The latter influence teaching conditions and student school performance. A Protocol was defined and parameters to be investigated were identified for acoustic characterization of unoccupied and occupied school environments, assessment of users by means of questionnaires completed by teachers and students, and vocal effort evaluation. Classrooms, laboratories, auditoriums, gymnasiums, common areas, canteens and outdoor areas were analysed in terms of acoustic features and identification of the origin of noise. The Protocol was tested in three kindergartens, three primary schools and three secondary schools placed in Rome, Florence and Perugia. Results of nine case studies are presented, including comparisons of objective and subjective investigations. Generally, the acoustic performances of the spaces under investigation do not meet the requirements of current Italian legislation. In particular, student activity determines high noise levels in laboratories, gymnasiums, and canteens. Students notice that noise mainly causes loss of concentration, fatigue, boredom, and headache. The outcomes of this research will be the starting point to define strategies and solutions for noise control and mitigation in schools and to draft guidelines for the acoustical school design