Latest Articles

Open AccessArticle
Relationship among Vulcanization, Mechanical Properties and Morphology of Blends Containing Recycled EPDM
Recycling 2017, 2(3), 16; doi:10.3390/recycling2030016 (registering DOI) -
Abstract
The production of consumption goods made of elastomer generates large amounts of vulcanized residues. The final proper environmental disposal of this material is a serious problem, which involves high costs and a possible waste of a material with high added value. The recycling
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The production of consumption goods made of elastomer generates large amounts of vulcanized residues. The final proper environmental disposal of this material is a serious problem, which involves high costs and a possible waste of a material with high added value. The recycling of elastomers is a very important alternative since it is related directly to the protection of the environment, energy conservation, and sustainability. An option for companies that produce elastomeric residues is their incorporation in the formulations by producing polymeric blends. Thus, this work aims to prepare polymeric blends composed of ethylene-propylene diene monomer rubber (EPDM) and raw EPDM/EPDM residue (EPDM-r) in different concentrations, when the residue is ground at room temperature. The morphology of the residue, vulcanization characteristics, mechanical properties, and morphology of the blends were analyzed, showing promising results that point to the feasibility of using EPDM-r in the production of polymeric blends and as a possible solution to the problem of the final disposal of solid residues. Full article
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Open AccessArticle
Pulling Exercises for Strength Training and Rehabilitation: Movements and Loading Conditions
J. Funct. Morphol. Kinesiol. 2017, 2(3), 33; doi:10.3390/jfmk2030033 (registering DOI) -
Abstract
The back is an extremely common site of injury among both athletes and sedentary people. Furthermore, low back pain has become prevalent in our society. Maintaining strong back muscles can help prevent future pain or injuries. Here, the aim is therefore to assess
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The back is an extremely common site of injury among both athletes and sedentary people. Furthermore, low back pain has become prevalent in our society. Maintaining strong back muscles can help prevent future pain or injuries. Here, the aim is therefore to assess the kinetic and kinematic movements of four pulling exercises with different external loading directions. Fifteen healthy subjects were analyzed using a 3D motion capture system. The pulley machine was equipped with a load cell for force data acquisition. The exercises consisted of 8 repetitions each of the lat pulldown (25% and 50% body weight (BW) extra load), the lat pulldown with 45° incline (10% and 25% BW), the seated cable row (25% and 50% BW) and the upright row (standing, 10% and 25% BW). The minimum and maximum curvature angle in the thoracic as well as the lumbar spine was larger during the upright row than during the other exercises. Furthermore, during the upright row, the sagittal moment in the shoulder joint is opposed to the other exercises in the direction of retroversion. Due to the higher lumbar curvature observed in low back patients, to avoid overload, it is not advisable for patients with back pain to perform upright rows. Full article
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Open AccessFeature PaperReview
Process and Pitfalls of Sperm Cryopreservation
J. Clin. Med. 2017, 6(9), 89; doi:10.3390/jcm6090089 (registering DOI) -
Abstract
Sperm cryopreservation has been utilized routinely for over 40 years to preserve fertility in men undergoing cancer therapy and allow conception for infertile couples. This article provides a concise and up-to-date review of the literature and covers the latest advances in sperm cryopreservation
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Sperm cryopreservation has been utilized routinely for over 40 years to preserve fertility in men undergoing cancer therapy and allow conception for infertile couples. This article provides a concise and up-to-date review of the literature and covers the latest advances in sperm cryopreservation and its array of clinical indications. Over recent years, the scope of clinical indications used for sperm cryopreservation has expanded widely. Consequently, more patient groups are eligible for sperm freezing, requiring specialist resources and higher running costs. Although sperm cryopreservation prior to cancer therapy is readily available in many countries, referral rates by oncology specialists and levels of patient engagement with cryopreservation services are both reported as low. Furthermore, sperm banking continues to raise ethical issues such whether sperm donation should be anonymous and whether sperm can be utilized posthumously by the surviving partner without consent from the patient. This review focuses on the technological advances and ethical controversies in sperm cryopreservation, and how better understanding of these issues could lead to improved access to fertility preserving treatment for patients. Full article
Open AccessArticle
The Effect of Access to Information and Communication Technology on Household Labor Income: Evidence from One Laptop Per Child in Uruguay
Economies 2017, 5(3), 35; doi:10.3390/economies5030035 (registering DOI) -
Abstract
This paper examines the effect of the One Laptop Per Child program in Uruguay (Plan Ceibal) on household labor income. Since 2007, the Uruguayan government has delivered one laptop to every child and teacher in public primary schools. This program has
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This paper examines the effect of the One Laptop Per Child program in Uruguay (Plan Ceibal) on household labor income. Since 2007, the Uruguayan government has delivered one laptop to every child and teacher in public primary schools. This program has considerably increased access to information technology within households, as evidenced by parents’ utilization of said technology. Households in the department of Florida received laptops in 2007, while those in the department of Canelones received them in 2009. Therefore, using data from Household Surveys from the National Institute of Statistics in Uruguay, a difference-in-difference model is estimated to capture the effect of the plan of giving laptops on labor income. The results indicate that there is a statistically significant positive effect of the plan on household labor income for households below median income, specifically, those at the 10th and 20th quantiles. Such findings suggest that the program has greater potential when targeted to low-income households, where parents possess lower computer skills. Full article
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Open AccessArticle
Using Historical Maps within a GIS to Analyze Two Centuries of Rural Landscape Changes in Southern Italy
Land 2017, 6(3), 65; doi:10.3390/land6030065 (registering DOI) -
Abstract
The current characteristics of a rural landscape may be better understood if suitable information related to its past is available. The availability of a Geographical Information System (GIS) can enable the analysis of landscape features in relation to several aspects, e.g., the evolution
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The current characteristics of a rural landscape may be better understood if suitable information related to its past is available. The availability of a Geographical Information System (GIS) can enable the analysis of landscape features in relation to several aspects, e.g., the evolution and mutual inter-relation among different ecosystems, the impact and sustainability of human activities, the visual characteristics of a landscape, etc. The analysis of geographical information, derived from historical maps, within a GIS could, therefore, prove to be a very powerful tool, for a better-informed decision-making and management of a rural landscape. With the aim to identify the land use changes in a rural area located in the Basilicata Region (Southern Italy), a territorial analysis was conducted through a GIS, in which data taken from historical maps—covering a period of 184 years, from 1829 to 2013—were implemented. Three-dimensional reconstruction of the rural landscape during different periods were obtained through digital terrain models (DTM). The land cover changes were also evaluated, demonstrating how they have affected the quality of the forest ecosystem in the area. The final results that were obtained comparing historical documents and current maps enabled the evaluation of the multi-temporal, morphological, and vegetation variations in this rural landscape. The analysis that was conducted has great potential for assessing and monitoring landscape diversity and typical changes of vegetation, even in different geographical locations, where appropriate interventions in landscape structures may be so planned. Full article
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Open AccessFeature PaperArticle
Control Strategies for Improving Energy Efficiency and Reliability in Autonomous Microgrids with Communication Constraints
Energies 2017, 10(9), 1443; doi:10.3390/en10091443 (registering DOI) -
Abstract
Microgrids are a feasible path to deploy smart grids, an intelligent and highly automated power system. Their operation demands a dedicated communication infrastructure to manage, control and monitor the intermittent sources of energy and loads. Therefore, smart devices will be connected to support
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Microgrids are a feasible path to deploy smart grids, an intelligent and highly automated power system. Their operation demands a dedicated communication infrastructure to manage, control and monitor the intermittent sources of energy and loads. Therefore, smart devices will be connected to support the growth of grid smartness increasing the dependency on communication networks, which consumes a high amount of power. In an energy-limited scenario, one of the main issues is to enhance the power supply time. Therefore, this paper proposes a hybrid methodology for microgrid energy management, integrated with a communication infrastructure to improve and to optimize islanded microgrid operation at maximum energy efficiency. The hybrid methodology applies some control management rules, such as intentional load shedding, priority load management, and communication energy saving. These energy saving rules establish a trade-off between increasing microgrid energy availability and communication system reliability. To achieve a compromised solution, a continuous time Markov chain model describes the impact of energy saving policies into system reliability. The proposed methodology is simulated and tested with the help of the modified IEEE 34 node test-system. Full article
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Open AccessReview
The α-Tubulin gene TUBA1A in Brain Development: A Key Ingredient in the Neuronal Isotype Blend
J. Dev. Biol. 2017, 5(3), 8; doi:10.3390/jdb5030008 (registering DOI) -
Abstract
Microtubules are dynamic cytoskeletal polymers that mediate numerous, essential functions such as axon and dendrite growth and neuron migration throughout brain development. In recent years, sequencing has revealed dominant mutations that disrupt the tubulin protein building blocks of microtubules. These tubulin mutations lead
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Microtubules are dynamic cytoskeletal polymers that mediate numerous, essential functions such as axon and dendrite growth and neuron migration throughout brain development. In recent years, sequencing has revealed dominant mutations that disrupt the tubulin protein building blocks of microtubules. These tubulin mutations lead to a spectrum of devastating brain malformations, complex neurological and physical phenotypes, and even fatality. The most common tubulin gene mutated is the α-tubulin gene TUBA1A, which is the most prevalent α-tubulin gene expressed in post-mitotic neurons. The normal role of TUBA1A during neuronal maturation, and how mutations alter its function to produce the phenotypes observed in patients, remains unclear. This review synthesizes current knowledge of TUBA1A function and expression during brain development, and the brain malformations caused by mutations in TUBA1A. Full article
Open AccessFeature PaperArticle
Measurement of Respiratory Chain Enzyme Activity in Human Renal Biopsy Specimens
J. Clin. Med. 2017, 6(9), 90; doi:10.3390/jcm6090090 (registering DOI) -
Abstract
Background: Mitochondrial disorders can present as kidney disease in children and be difficult to diagnose. Measurement of mitochondrial function in kidney tissue may help diagnosis. This study was to assess the feasibility of obtaining renal samples and analysing them for respiratory chain
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Background: Mitochondrial disorders can present as kidney disease in children and be difficult to diagnose. Measurement of mitochondrial function in kidney tissue may help diagnosis. This study was to assess the feasibility of obtaining renal samples and analysing them for respiratory chain enzyme activity. Methods: The subjects were children undergoing a routine diagnostic renal biopsy, in whom a clinical condition of renal inflammation, scarring and primary metabolic disorder was unlikely. A fresh sample of kidney was snap frozen and later assayed for the activities of respiratory chain enzyme complexes I, II/III, and IV using spectrophotometric enzyme assay, and expressed as a ratio of citrate synthase activity. Results: The range of respiratory chain enzyme activity for complex I was 0.161 to 0.866 (mean 0.404, SD 0.2), for complex II/III was 0.021 to 0.318 (mean 0.177, SD 0.095) and for complex IV was 0.001 to 0.025 (mean 0.015, SD 0.006). There were correlations between the different activities but not between them and the age of the children or a measure of the amount of chronic damage in the kidneys. Conclusion: It is feasible to measure respiratory chain enzyme activity in routine renal biopsy specimens. Full article
Open AccessFeature PaperArticle
Comparison of Different Minimal Velocity Thresholds to Establish Deadlift One Repetition Maximum
Sports 2017, 5(3), 70; doi:10.3390/sports5030070 (registering DOI) -
Abstract
The aim of this study was to compare the actual deadlift one repetition maximum (1RM) and the deadlift 1RM predicted from individualised load-velocity profiles. Twelve moderately resistance-trained men participated in three deadlift sessions. During the first, 1RM was assessed; during the second, load-velocity
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The aim of this study was to compare the actual deadlift one repetition maximum (1RM) and the deadlift 1RM predicted from individualised load-velocity profiles. Twelve moderately resistance-trained men participated in three deadlift sessions. During the first, 1RM was assessed; during the second, load-velocity profiles were recorded with six loads (65% to 90% 1RM) using a linear position transducer recording at 1000 Hz; and during the third, minimal velocity thresholds (MVT) were recorded from the velocity of the last repetition during sets to volitional fatigue with 70% and 80% 1RM with a linear position transducer recording at 1000 Hz. Regression was then used to generate individualised load-velocity profiles and the MVT was used as a cut-off value from which to predict deadlift 1RM. In general, velocity reliability was poor to moderate. More importantly, predicted deadlift 1RMs were significantly and meaningfully less than actual deadlift 1RMs (p < 0.05, d = 1.03–1.75). The main practical application that should be taken from the results of this study is that individualized load-velocity profiles should not be used to predict deadlift 1RM. Practitioners should not use this method in combination with the application of MVT obtained from the last repetition of sets to volitional fatigue. Full article
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