402 research outputs found
Corrosion of cast aluminum alloys: a review
Research on corrosion resistance of cast aluminum alloys is reviewed in this article. The effect of the main microstructural features of cast aluminum alloys such as secondary dendrite arm spacing (SDAS), eutectic silicon morphology, grain size, macrosegregation, microsegregation, and intermetallic compounds is discussed. Moreover, the corrosion resistance of cast aluminum alloys obtained by modern manufacturing processes such as semi-solid and additive manufacturing are analyzed. Finally, the protective effects provided by different coatings on the aluminum cast alloys?such as anodized, plasma electrolytic oxidation (PEO), and laser?is reviewed. Some conclusions and future guidelines for future works are proposed
PO-1134 Using e-Learning to improve RTTs training: the case of a Skills e-Lab for the TrueBeam
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First steps in the logic-based assessment of post-composed phenotypic descriptions
In this paper we present a preliminary logic-based evaluation of the integration of post-composed phenotypic descriptions with domain ontologies. The evaluation has been performed using a description logic reasoner together with scalable techniques: ontology modularization and approximations of the logical difference between ontologies
A systematic review on the muscular activation on the lower limbs with five different variations of the deadlift exercise
The deadlift is one of the most widely used resistance exercises by different types of trainees and with different aims including aesthetics, performance and health. There are numerous variations of the deadlift exercise which have different effects on the exercise biomechanics and muscular activation. The main objective of this research was to systematically review the literature looking forward to gathering data on the muscular activation on the lower limbs with different variations of the deadlift exercise (conventional, sumo, Romanian, straight legs and hex-bar). 19 articles met the inclusion criteria and were included in the analysis. Quality of the articles was assessed through the PEDro scale. Main findings were that deadlift is a posterior-chain dominant exercise. Changes in activation between the variations majorly depend on the hip flexion in relation to the knee flexion. For instance, the straight-legs deadlift does not involve knee flexion and mainly activates hip extensors. Other factors such as the distance between the load and the centre of mass, the knee flexion planes, or the total intensity also condition the muscular activation. For example, the hex-bar deadlift allows the subject being in alignment with the load and performing the exercise with relatively vertical back, which provokes an increase on the activation of the knee extensors. In conclusion, this study may help the strength and conditioning professionals and practitioners with the exercise selection depending on the muscular targets and the individual characteristics of the athlete
Incidence and prevalence of injuries in futsal: A systematic review of the literature
Futsal athletes are exposed to a high number of injures. Purpose: This study aimed to gather data on the injures produced in futsal, attending to the prevalence, part of the body injured, type of injury and mechanism, and severity. Also, to evaluate the influence that sociodemographic factors and the position on the pitch may have on the injuries. Finally, we pursued to summarize the prevention strategies proposed by the expert literature. Design: Different search strategies were entered in PubMed, Scopus, Web of Science, and Sport Discuss databases. Results: 36 articles were selected to be reviewed. Futsal is situated among the sports with the highest injury incidence, being the main body part injured the lower limb, specifically the knees and ankles. Regarding the type of injury and the mechanism causing the injury, bone injuries are usually related to contact with rivals and muscle, tendon, and ligament injuries related to non-contact mechanisms. In this concern, non-contact injuries are frequently more severe than impact injuries. There is not a clear consensus on if more injuries occur in training or games, and on the severity of the major part of the injuries that occur in futsal. Concerning sex, male players seem to present a higher prevalence of ankle injuries while woman players present more incidence of knee sprains. The age was reported to be correlated with the incidence of injuries during futsal practice. No influence of the position on the field of play on the prevalence of injuries was observed in the literature. Some recommendations are gathered concerning the prevention of injuries. These recommendations are focused on player equipment, playing facilities, rules, physical assessment, and appropriate strength and conditioning preparation. Conclusion: The results presented in this study may help coaches and practitioners to understand crucial factors on the common injuries that occur in futsal. This may allow them to prevent potential injuries and maintain the athlete’s performance
Resistance training for chronic low back pain in the elderly: A systematic review
Chronic low back pain is a musculoskeletal pathology with a considerably high prevalence in the elderly. This condition increases disability and negatively affects the quality of life. Muscular resistance training is being used as a cornerstone in interventions for elder people due to the numerous benefits associated with physical and functional health. For this reason, the purpose of this study was to systematically review the literature on the main characteristics of resistance training programs in the elder population with chronic low back pain. A literature search in five databases (PubMed, Scopus, Web of Science, Sports Discuss, and Cochrane Library) was carried out. Inclusion-exclusion criteria were used to select experimental studies applying resistance training programs to aging adults older than 60 ages with chronic lumbar pain. PEDro scale was used to evaluate the quality of the included studies. From the first 223 articles retrieved, 8 were selected to be further analysed. All the studies presented good methodological quality (PEDro scale from 6 to 10) and low bias risk. In summary, resistance training programs have been proven useful to significantly reduce pain and inability. Furthermore, significant improvements in quality of life and muscular strength parameters are guaranteed
A new sports garment with elastomeric technology optimizes physiological, mechanical, and psychological acute responses to pushing upper-limb resistance exercises
This study aimed to compare the mechanical (lifting velocity and maximum number
of repetitions), physiological (muscular activation, lactate, heart rate, and blood
pressure), and psychological (rating of perceived exertion) responses to upper-body
pushing exercises performed wearing a sports elastomeric garment or a placebo
garment. Nineteen physically active young adults randomly completed two training
sessions that differed only in the sports garment used (elastomeric technology or
placebo). In each session, subjects performed one set of seated shoulder presses and
another set of push-ups until muscular failure. The dependent variables were
measured immediately after finishing the set of each exercise. Compared to the
placebo garment, the elastomeric garment allowed participants to obtain greater
muscular activation in the pectoralis major (push-ups: p = 0.04, d = 0.49; seated
shoulder press: p < 0.01, d = 0.64), triceps brachialis (push-ups, p < 0.01, d = 0.77;
seated shoulder press: p < 0.01, d = 0.65), and anterior deltoid (push-ups: p < 0.01,
d = 0.72; seated shoulder press: p < 0.01, d = 0.83) muscles. Similarly, participants
performed more repetitions (push-ups: p < 0.01; d = 0.94; seated shoulder press:
p = 0.03, d = 0.23), with higher movement velocity (all p ≤ 0.04, all d ≥ 0.47), and
lower perceived exertion in the first repetition (push-ups: p < 0.01, d = 0.61; seated
shoulder press: p = 0.05; d = 0.76) wearing the elastomeric garment compared to
placebo. There were no between-garment differences in most cardiovascular
variables (all p ≥ 0.10). Higher diastolic blood pressure was only found after the
seated shoulder press wearing the elastomeric garment compared to the placebo
(p = 0.04; d = 0.49). Finally, significantly lower blood lactate levels were achieved in
the push-ups performed wearing the elastomeric garment (p < 0.01; d = 0.91), but no
significant differences were observed in the seated shoulder press (p = 0.08). Overall,
the findings of this study suggest that elastomeric technology integrated into a sports garment provides an ergogenic effect on mechanical, physiological, and
psychological variables during the execution of pushing upper-limb resistance
exercises
Heterogeneity in Multiple Sclerosis: Scratching the Surface of a Complex Disease
Multiple Sclerosis (MS) is the most common demyelinating disease of the central nervous system. Although the etiology and the pathogenesis of MS has been extensively investigated, no single pathway, reliable biomarker, diagnostic test, or specific treatment have yet been identified for all MS patients. One of the reasons behind this failure is likely to be the wide heterogeneity observed within the MS population. The clinical course of MS is highly variable and includes several subcategories and variants. Moreover, apart from the well-established association with the HLA-class II DRB1*15:01 allele, other genetic variants have been shown to vary significantly across different populations and individuals. Finally both pathological and immunological studies suggest that different pathways may be active in different MS patients. We conclude that these “MS subtypes” should still be considered as part of the same disease but hypothesize that spatiotemporal effects of genetic and environmental agents differentially influence MS course. These considerations are extremely relevant, as outcome prediction and personalised medicine represent the central aim of modern research
An Expanded 2D Fused Aromatic Network with 90-Ring Hexagons
Two-dimensional fused aromatic networks (2D FANs) have emerged as a highly versatile alternative to holey graphene. The synthesis of 2D FANs with increasingly larger lattice dimensions will enable new application perspectives. However, the synthesis of larger analogues is mostly limited by lack of appropriate monomers and methods. Herein, we describe the synthesis, characterisation and properties of an expanded 2D FAN with 90-ring hexagons, which exceed the largest 2D FAN lattices reported to date
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