231 research outputs found
Overestimation of numerical distances in the left space
No full textNormal subjects presented with a middle number and two left- and right-sided outer numbers overestimate the numerical distance between the middle number and that positioned at its left side. Repetitive transcranial magnetic stimulation (rTMS) of the right posterior parietal cortex specifically counteracts this bias, suggesting that the mental representation of space defined by numbers is shifted toward the left side depending on a greater activity of the right hemisphere
MANUFACTURE AND CHARACTERIZATION OF CONTINUOUS SIC FIBER REINFORCED ALUMINUM COMPOSITES BY LOW-PRESSURE PLASMA SPRAYING
No full textTHE FEASIBILITY OF THE LOW PRESSURE PLASMA SPRAYING (LPPS) PROCESS FOR PRODUCING CONTINUOUS FIBER REINFORCED METAL MATRIX COMPOSITES IS EVALUATED ON A LABORATORY SCALE. THE REINFORCEMENT USED WAS 140 MICRON DIAMETER SIC/C LONG FIBERS, WHILE ALUMINIUM WAS DEPOSITED AS MATRIX MATERIAL. RESULTS OF PRELIMINARY CHARACTERIZATION TESTS ARE PRESENTED, IN ORDER TO EVALUATE THE OVERALL QUALITY OF THE COMPOSITE. SCANNING ELECTRON MICROSCOPY, ENERGY DISPERSIVE SPECTROSCOPY, X-RAY DIFFRACTION ANALYSIS AND ROOM TEMPERATURE TENSILE TESTS WERE CARRIED OUT ON SPRAYED COMPOSITE MONOTAPES. THE LONG RAGE DIFFUSION OF CHEMICAL REACTIONS PRODUCTS IN THE INTERFACIAL ZONE WAS INVESTIGATED, AFFECTING MECHANICAL PROPERTIES OF THE COMPOSITE, WITH SPECIAL REFERENCE TO ULTIMATE TENSILE STRENGTH AND STRAIN. PLASMA SPRAYING FABRICATION METHOD SEEMS PROMISING IN REDUCING COST AND IMPROVING QUALITY OF THE FINAL PRODUCTS. THE WIDESPREAD APPLICATION OF LPPS AS A PRODUCTION TECHNIQUE FOR MMCS CAN BE ANTICIPATED. NEVERTHELESS FURTHER RESEARCH AND DEVELOPMENT ACTIVITIES ARE REQUIRED TO REVEAL AND TO REALIZE THE TRUE POTENTIAL OF THESE MATERIALS
Levels of cognitive functioning assessment scale: italian cross-cultural adaptation and validation
No full textStudy design. Cross-sectional study. Objective. To develop an Italian version of the Levels of Cognitive Functioning Assessment Scale (LOCFAS) and examine its reliability and validity. Subject. Patients with acquired brain injury in an early post-coma state. Methods. The original scale was translated from English to Italian using the guidelines set forth in the Translation and Cultural Adaptation of Patient Reported Outcomes Measures-Principles of Good Practice. Intra-rater reliability was examined using the intraclass correlation coefficient (ICC). Concurrent validity was evaluated using Pearson's correlation coefficients with some of the functional and disability components of the International Classification of Functioning, Disability and Health (ICF), excluding environmental factors. Setting. The highly specialized neurorehabilitation department of "San Raffaele" Hospital, Cassino. Results. The Italian version of the LOCFAS (LOCFAS-I) was administered to 38 subjects from May 9, 2017 to August 31, 2017. The mean ± SD of the LOCFAS-I score was 3.05 ± 1.88. All LOCFAS-I items were either identical or similar in meaning to the original version's items. Test-retest reliability (ICC) was 0.996 (p < 0.01). The Pearson correlation coefficient of the LOCFAS-I scores with some of the functional and disability components of the ICF was > 0.536 (p < 0.01). Conclusions. The LOCFAS-I was found to be reliable and a valid measurement tool for the assessment of cognitive functioning post-coma in the Italian population
Effects of low-gamma tACS on primary motor cortex in implicit motor learning
No full textIn the primary motor cortex (M1), rhythmic activity in the gamma frequency band has been found during movement planning, onset and execution. Although the role of high-gamma oscillatory activity in M1 is well established, the contribution of low-gamma activity is still unexplored. In this study, transcranial alternating current stimulation (tACS) was used with the aim to specifically modulate low-gamma frequency band in M1, during an implicit motor learning task. A 40 Hz-tACS was applied over the left M1 while participants performed a serial reaction time task (SRTT) using their right hand. The task required the repetitive execution of sequential movements in response to sequences of visual stimuli. Sequential blocks were interleaved by a random block, which served as interference to sequence learning. Sham and 1 Hz tACS were used as control. Task performance was examined before, during and after tACS (pre-, online- and post-phase, respectively). Furthermore, cortical reactivity of M1 was assessed in the pre- and post-tACS phases, by measuring motor-evoked potentials (MEPs) elicited by single-pulse transcranial magnetic stimulation (TMS).
Compared to sham and pre-tACS, the 40 Hz stimulation applied during SRTT slowed down response times in blocks that required retrieving previously learned sequences, after performing the random block. In addition, M1 cortical reactivity was selectively inhibited following 40 Hz-tACS, as quantified by reduced MEP amplitude. These results show that low-gamma tACS delivered over M1 during motor learning enhanced susceptibility to interference generated by the random sequence (i.e., proactive interference effect). Importantly, only low-gamma stimulation produced long-lasting effects on M1 cortical reactivity
Complications in total thyroidectomy: our experience and a number of considerations.
No full textThe authors review 1,636 cases of total thyroidectomy with reference to specific complications, classifying them under the headings: major-minor, early-late, transitory-definitive. They report 19 cases of postsurgical haemorrhage, all within 12 hours of the operation, 31 transitory and 15 definitive cases of recurrent laryngeal nerve paralysis, and 14 cases of definitive hypoparathyroidism. As far as the minor complications were concerned, there was a greater incidence of seroma following the use of the harmonic scalpel. The risk factors and physiopathological mechanisms associated with each type of complication are analysed here, above all those responsible for the major and definitive complications. The need for routine preparation of the recurrent nerve, in order to prevent occurrence of postsurgical paralysis is stressed, as is the efficacy of vitamin D in preventing symptomatic postsurgical hypocalcaemia
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