The Effect of rest interval between sets on the number of repetitions performed in the bench press exercise

The aim of the present study was to analyze the effects of different rest intervals on the number of repetitions performed in the bench press exercise. Methods: 6 resistance-trained men (age 24.27±1.61 years, body fat 14.72±5.32 %, body mass 76.60±11.00 kg, 1-RM bench press 98.42±19.78kg) volunteered for the study. Subjects performed a bench press 1-RM test and in two subsequent sessions they performed five maximal sets of the bench press exercise with 70%, 75%, 75%, 80% and 85% of 1-RM and a 1- or 2-minute rest interval between sets. Sessions occurred at least 48h apart, with the last two in a random fashion. Statistical analyzes was made by the student t-test to compare the differences between rest intervals. The number of repetitions performed with the 2-minute rest interval (33.16 ± 6.14) was significantly higher than with 1-minute rest interval (26.67 ± 3.44), (p=0.009) and in sets 2 (p=0.016), 3 (p=0.004) and 4 (p=0.018). The 2-minute rest interval yielded a larger number of repetitions performed throughout the five sets of bench press. Furthermore, the subjects were unable to maintain a large number of repetitions even when a 2-minute rest interval was taken. This indicates that larger rest intervals may be necessary when training with this intensity, especially if the maintenance of exercise volume is desired

Determination of optimum combination of voxel size and b-value for brain diffusion tensor imaging

Optimum combination of voxel size resolution and b-value for whole brain imaging has been determined. Data images were acquired using a 1.5T magnetic resonance imaging (MRI) system (GE Signa HDxt). Diffusion tensor imaging (DTI) scan was performed on phantom and a human volunteer. Six protocols which consist of various combination of voxel size and b-value were evaluated. Measurement of signal-to-noise ratio (SNR) and DTI parameter indices were carried out for both phantom and in-vivo studies. Due consideration was given to a combination of parameters yielding sufficient SNR with DTI values comparable to those obtained from previous reported studies. For the phantom study, SNR ≥ 20 was found in all of the protocols except for a combination of voxel size of 2.0 × 2.0 × 2.0 mm3 with b-value of 1200 s/mm2 (V2.0 B1200) and that of voxel size of 2.0 × 2.0 × 2.0 mm3 with b-value of 1000 s/mm2 (V2.0 B1000). For in-vivo study, all protocols presented SNR > 20. It was found that a combination of voxel size of 2.5 × 2.5 × 2.5 mm3 with b-value of 1000 s/mm2 (V2.5 B1000) and that of voxel size of 2.5 × 2.5 × 2.5 mm3 with b-value of 700 s/mm2 (V2.5 B700) displayed the most comparable ADC and FA values with references. In terms of anatomic coverage, V2.5 B700 was found better than V2.5 B1000 as it assures coverage of the whole brain. In conclusion, a combination of voxel size of 2.5 × 2.5 × 2.5 mm3 with b-value of 700 s/mm2 was considered as optimum parameters for brain DTI

Investigation of the SpinChem® rotating bed reactor: internally and externally mass transfer limited reactions

In questo lavoro lo SpinChem® rotating bed reactor è stato confrontato con un comune reattore slurry (stirred tank reactor), per diverse velocità di rotazione, usando due reazioni solido-liquido non-catalitiche: la rimozione di unaimpurità genotossica da una soluzione e una reazione di scambio ionicoope

Investigation of the potential of gelucire 44/14 for enhancing oral bioavailability using two model drugs [RS199.5. M211 2007 f rb].

Dua drug model yang termasuk dalam dua kumpulan Biopharmaceutics Classification System (BCS) yang berbeza, iaitu vancomycin (VCM), satu sebatian kelas III (keterlarutan tinggi dan ketelapan rendah), dan griseofulvin, satu drug kelas II (keterlarutan rendah and ketelapan tinggi) telah digunakan untuk menilai potensi satu pembawa gliserida berpoliglikol, iaitu Gelucire 44/14, untuk meningkatkan biokeperolehan oral. Two model drugs belonging to different groups of the Biopharmaceutics Classification System (BCS), which are vancomycin (VCM) as a class III drug (high solubility and low permeability) and griseofulvin (GF) as a class II drug (low solubility and high permeability), were employed to evaluate the potential of a polyglycolised glyceride carrier, namely Gelucire 44/14, to enhance their oral bioavailability

Occupational risk due to use of mercury in dentistry: a bibliographic review

Este trabalho visa apresentar dados referentes ao gerenciamento de resíduos perigosos na área da saúde, com ênfase no uso de mercúrio em odontologia. Foi elaborado com base numa revisão bibliográfica sobre o uso do mercúrio em amálgama dentário e seus potenciais riscos toxicológicos ligados à exposição, tanto de profissionais quanto de pacientes. Os estudos levantados baseiam-se também em recomendações de alguns organismos internacionais e nacionais em relação ao uso do mercúrio e seus limites de exposição ocupacional. Os dados da literatura revelam o potencial tóxico do mercúrio, tanto para o ambiente quanto para a saúde humana. Tendo em vista que o amálgama ainda é muito utilizado na odontologia, considera-se necessário uma tomada de decisão político-administrativa que vise minimizar os riscos relacionados ao uso de amálgama em procedimentos odontológicos, voltados para a segurança ocupacional, dos indivíduos e do ambiente, baseada em diretrizes e orientações técnicas sobre seu uso, descarte e disposição final.The aim of this study is to present data concerning hazardous waste management in the health area, with emphasis to the utilization of mercury in dentistry. The study was based on a bibliographic review regarding the use of mercury in dental fillings and its potential toxicological risks for patients and due to occupational exposure. The studies also take into consideration national and international recommendations on the use of mercury and its occupational exposure limits. The review of the literature reveals the potential toxic effects of mercury both on the environment and on human health. Given that the use of dental amalgam is still very frequent in dentistry, there is a need for safety regulations in order to minimize the risks posed by dental amalgam in dentistry proceedings based on technical guidelines for its use, discard and final disposal

The strength of anticipated distractors shapes EEG alpha and theta oscillations in a Working Memory task

: Working Memory (WM) requires maintenance of task-relevant information and suppression of task-irrelevant/distracting information. Alpha and theta oscillations have been extensively investigated in relation to WM. However, studies that examine both theta and alpha bands in relation to distractors, encompassing not only power modulation but also connectivity modulation, remain scarce. Here, we depicted, at the EEG-source level, the increase in power and connectivity in theta and alpha bands induced by strong relative to weak distractors during a visual Sternberg-like WM task involving the encoding of verbal items. During retention, a strong or weak distractor was presented, predictable in time and nature. Analysis focused on the encoding and retention phases before distractor presentation. Theta and alpha power were computed in cortical regions of interest, and connectivity networks estimated via spectral Granger causality and synthetized using in/out degree indices. The following modulations were observed for strong vs. weak distractors. In theta band during encoding, the power in frontal regions increased, together with frontal-to-frontal and bottom-up occipital-to-temporal-to-frontal connectivity; even during retention, bottom-up theta connectivity increased. In alpha band during retention, but not during encoding, the power in temporal-occipital regions increased, together with top-down frontal-to-occipital and temporal-to-occipital connectivity. From our results, we postulate a proactive cooperation between theta and alpha mechanisms: the first would mediate enhancement of target representation both during encoding and retention, and the second would mediate increased inhibition of sensory areas during retention only, to suppress the processing of imminent distractor without interfering with the processing of ongoing target stimulus during encoding

Deep learning-based EEG analysis: investigating P3 ERP components

The neural processing of incoming stimuli can be analysed from the electroencephalogram (EEG) through event-related potentials (ERPs). The P3 component is largely investigated as it represents an important psychophysiological marker of psychiatric disorders. This is composed by several subcomponents, such as P3a and P3b, reflecting distinct but interrelated sensory and cognitive processes of incoming stimuli. Due to the low EEG signal-to-noise-ratio, ERPs emerge only after an averaging procedure across trials and subjects. Thus, this canonical ERP analysis lacks in the ability to highlight EEG neural signatures at the level of single-subject and single-trial. In this study, a deep learning-based workflow is investigated to enhance EEG neural signatures related to P3 subcomponents already at single-subject and at single-trial level. This was based on the combination of a convolutional neural network (CNN) with an explanation technique (ET). The CNN was trained using two different strategies to produce saliency representations enhancing signatures shared across subjects or more specific for each subject and trial. Cross-subject saliency representations matched the signatures already emerging from ERPs, i.e., P3a and P3b-related activity within 350–400 ms (frontal sites) and 400–650 ms (parietal sites) post-stimulus, validating the CNN+ET respect to canonical ERP analysis. Single-subject and single-trial saliency representations enhanced P3 signatures already at the single-trial scale, while EEG-derived representations at single-subject and single-trial level provided no or only mildly evident signatures. Empowering the analysis of P3 modulations at single-subject and at single-trial level, CNN+ET could be useful to provide insights about neural processes linking sensory stimulation, cognition and behaviour

The Sensory-Cognitive Interplay: Insights into Neural Mechanisms and Circuits

Senses are our interface for acting in the external world. Consequently, sensory-motor information grounds and drives our higher cognitive processes. At the same time, we are impinged by a multitude of sensory inputs with variable saliency. It is therefore crucial that the process- ing of sensory inputs and motor signals is modulated by cognitive and executive mechanisms such as expectation, memory, attention, emotion, planning, monitoring. This is needed to highlight sensory information that is currently rel- evant for task goals, and to adapt motor control and behav- ior accordingly. The strict intertwining of sensory, motor, and cognitive functions is evidenced in aging and in neuro- logical disorders. Indeed, sensory-motor dysfunctions of- ten accompany higher-level dysfunctions in older popula- tions [1] and in neurological subjects (e.g., in dyslexia, at- tention deficit hyperactivity disorders, or autism spectrum disorders) [2,3] [...

A Computational Model of the Lexical-Semantic System Based on a Grounded Cognition Approach

This work presents a connectionist model of the semantic-lexical system based on grounded cognition. The model assumes that the lexical and semantic aspects of language are memorized in two distinct stores. The semantic properties of objects are represented as a collection of features, whose number may vary among objects. Features are described as activation of neural oscillators in different sensory-motor areas (one area for each feature) topographically organized to implement a similarity principle. Lexical items are represented as activation of neural groups in a different layer. Lexical and semantic aspects are then linked together on the basis of previous experience, using physiological learning mechanisms. After training, features which frequently occurred together, and the corresponding word-forms, become linked via reciprocal excitatory synapses. The model also includes some inhibitory synapses: features in the semantic network tend to inhibit words not associated with them during the previous learning phase. Simulations show that after learning, presentation of a cue can evoke the overall object and the corresponding word in the lexical area. Moreover, different objects and the corresponding words can be simultaneously retrieved and segmented via a time division in the gamma-band. Word presentation, in turn, activates the corresponding features in the sensory-motor areas, recreating the same conditions occurring during learning. The model simulates the formation of categories, assuming that objects belong to the same category if they share some features. Simple exempla are shown to illustrate how words representing a category can be distinguished from words representing individual members. Finally, the model can be used to simulate patients with focalized lesions, assuming an impairment of synaptic strength in specific feature areas