Guide Specification for Highway Construction Texturing Concrete Pavement for Reduced Tire/Pavement Noise using Artificial Turf Drag, March 1, 2011

This document provides language that can be used by an Owner-Agency to develop materials and construction specifications with the objective of reducing tire/pavement noise. While the practices described herein are largely prescriptive, they have been demonstrated to increase the likelihood of constructing a durable, quieter concrete surface. Guidance is provided herein for texturing the concrete surface since texture geometry has a paramount effect on tire/pavement noise. Guidance for curing is also provided to improve strength and durability of the surface mortar, and thus to improve texture durability.

Toxicological Assessment of Coated versus Uncoated Rubber Granulates Obtained from Used Tires for Use in Sport Facilities

Reuse of tire crumb in sport facilities is currently a very cost-effective waste management measure. Considering that incorporation of the waste materials in artificial turf would be facilitated if the rubber materials were already colored green, coatings were specifically developed for this purpose. This paper presents an experimental toxicological and environmental assessment aimed at comparing the obtained emissions to the environment in terms of polycyclic aromatic hydrocarbons (PAHs), heavy metals, and ecotoxicity for coated and noncoated rubber granulates. This study is a comprehensive evaluation of the major potential critical factors related with the release of all of these classes of pollutants because previous studies were not systematically performed. It was concluded that between the two types of coatings tested, one is particularly effective in reducing emissions to the environment, simultaneously meeting the requirements of adherence and color stability.

Influência do tipo de chuteira em variáveis preditoras do risco de entorse lateral do tornozelo

Introdução: No futebol, a entorse lateral do tornozelo (ELT) destaca-se como sendo a lesão mais prevalente. Potenciada pela variedade de chuteiras disponíveis no mercado e pela crescente utilização de relvados sintéticos, a interação entre o terreno e o calçado tem assumido elevada relevância como fator de risco para a ELT. A maior incidência de lesões na 2ª parte do jogo traduz a necessidade do estudo dessa interação durante tarefas que envolvam fadiga. Objetivo: Estudar a influência das chuteiras em variáveis preditoras do risco de ELT em relvado sintético sob duas condições: sem e com fadiga dos músculos eversores do tornozelo Métodos: Foi utilizada uma amostra de atletas saudáveis. Todos os indivíduos realizaram 3 séries de 5 saltos médio-laterais uni-podálicos, cada uma com 1 de 3 modelos de chuteiras (Turf, Hard e Firm ground) em duas condições: sem e com fadiga induzida pelo dinamómetro isocinético. Durante a tarefa, a atividade eletromiográfica do longo e curto peroniais, o valor das forças de reação do solo e o movimento do retro-pé (plano frontal), foram recolhidos e usados para calcular variáveis cinemáticas (eversão/inversão do tornozelo, o deslocamento e velocidade do centro de pressão), cinéticas (taxa de crescimento das forças de reação do solo) e neuromusculares (tempo de ativação muscular dos peroniais). Resultados: À exceção do tempo de ativação do curto peronial com o modelo Hard ground (sem fadiga vs com fadiga (p=0,050), não foram identificadas diferenças estatisticamente significativas nas variáveis preditoras de lesão, entre chuteiras, nem entre as duas condições avaliadas. Conclusão: Para o teste funcional escolhido e executado por atletas saudáveis em sintético de 3ª geração, nenhuma das chuteiras apresenta maior risco de lesão (com e sem fadiga), tendo em conta as variáveis em estudo.

Toxicological Assessment of Coated versus Uncoated Rubber Granulates Obtained from Used Tires for Use in Sport Facilities

Reuse of tire crumb in sport facilities is currently a very cost-effective waste management measure. Considering that incorporation of the waste materials in artificial turf would be facilitated if the rubber materials were already colored green, coatings were specifically developed for this purpose. This paper presents an experimental toxicological and environmental assessment aimed at comparing the obtained emissions to the environment in terms of polycyclic aromatic hydrocarbons (PAHs), heavy metals, and ecotoxicity for coated and noncoated rubber granulates. This study is a comprehensive evaluation of the major potential critical factors related with the release of all of these classes of pollutants because previous studies were not systematically performed. It was concluded that between the two types of coatings tested, one is particularly effective in reducing emissions to the environment, simultaneously meeting the requirements of adherence and color stability.

Variations of Tine Texturing of PCC Pavement, MLR-93-4, 1996

Seven experimental texture sections were constructed on the Polk-Jasper RP-163-1(50)--16--77 project just east of Des Moines. The experimental sections included two groove depths for a longitudinal tine texture and 13 mm (1/2 in.), 19 mm (1 in.) and variable spaced transverse tine textures. An artificial turf textured section was also included. Friction values and a rating of objectionable noise were determined for all sections. All transverse tine textures generated a high level of objectionable noise. The longitudinal tine texture was rated very good in regard to objectionable noise. At this time, all tined textures are providing satisfactory friction values.

Neuro-mechanical and metabolic adjustments to the repeated anaerobic sprint test in professional football players.

PURPOSE: This study aimed to determine the neuro-mechanical and metabolic adjustments in the lower limbs induced by the running anaerobic sprint test (the so-called RAST). METHODS: Eight professional football players performed 6 × 35 m sprints interspersed with 10 s of active recovery on artificial turf with their football shoes. Sprinting mechanics (plantar pressure insoles), root mean square activity of the vastus lateralis (VL), rectus femoris (RF), and biceps femoris (BF) muscles (surface electromyography, EMG) and VL muscle oxygenation (near-infrared spectroscopy) were monitored continuously. RESULTS: Sprint time, contact time and total stride duration increased from the first to the last repetition (+17.4, +20.0 and +16.6 %; all P < 0.05), while flight time and stride length remained constant. Stride frequency (-13.9 %; P < 0.001) and vertical stiffness decreased (-27.2 %; P < 0.001) across trials. Root mean square EMG activities of RF and BF (-18.7 and -18.1 %; P < 0.01 and 0.001, respectively), but not VL (-1.2 %; P > 0.05), decreased over sprint repetitions and were correlated with the increase in running time (r = -0.82 and -0.90; both P < 0.05). Together with a better maintenance of RF and BF muscles activation levels over sprint repetitions, players with a better repeated-sprint performance (lower cumulated times) also displayed faster muscle de- (during sprints) and re-oxygenation (during recovery) rates (r = -0.74 and -0.84; P < 0.05 and 0.01, respectively). CONCLUSION: The repeated anaerobic sprint test leads to substantial alterations in stride mechanics and leg-spring behaviour. Our results also strengthen the link between repeated-sprint ability and the change in neuromuscular activation as well as in muscle de- and re-oxygenation rates.

Análisis del coste económico del uso de la superficie de césped sintético por futbolista en campos de fútbol públicos. Estudio de casos

[ES]El presente artículo ahonda en el análisis de la realidad acerca de los costes de reponer y utilizar superficies deportivas de césped artificial, centrando sus indagaciones en el caso del fútbol, deporte mayoritario en cuanto a participación en España. La metodología empleada en el análisis se basa en un estudio de casos, buscando esclarecer principalmente, el coste de un único uso por jugador y por equipo en un campo de fútbol de césped artificial. En el estudio que nos ocupa, hemos basado la investigación en dos espacios deportivos completamente opuestos en cuanto a su ocupación, al objeto de conocer el importe económico a satisfacer por cada usuario o equipo. El estudio posee unos objetivos muy concretos que se centran en procesar el análisis y conseguir datos reveladores de la realidad de las superficies sintéticas de fútbol, así como determinar y validar unos indicadores que son la base del estudio.

Update On Ultraviolet A And B Radiation Generated By The Sun And Artificial Lamps And Their Effects On Skin.

Solar radiation, especially ultraviolet A (UVA) and ultraviolet B (UVB), can cause damage to the human body, and exposure to the radiation may vary according to the geographical location, time of year and other factors. The effects of UVA and UVB radiation on organisms range from erythema formation, through tanning and reduced synthesis of macromolecules such as collagen and elastin, to carcinogenic DNA mutations. Some studies suggest that, in addition to the radiation emitted by the sun, artificial sources of radiation, such as commercial lamps, can also generate small amounts of UVA and UVB radiation. Depending on the source intensity and on the distance from the source, this radiation can be harmful to photosensitive individuals. In healthy subjects, the evidence on the danger of this radiation is still far from conclusive.

Artificial Gait In Complete Spinal Cord Injured Subjects: How To Assess Clinical Performance.

Objective Adapt the 6 minutes walking test (6MWT) to artificial gait in complete spinal cord injured (SCI) patients aided by neuromuscular electrical stimulation. Method Nine male individuals with paraplegia (AIS A) participated in this study. Lesion levels varied between T4 and T12 and time post injured from 4 to 13 years. Patients performed 6MWT 1 and 6MWT 2. They used neuromuscular electrical stimulation, and were aided by a walker. The differences between two 6MWT were assessed by using a paired t test. Multiple r-squared was also calculated. Results The 6MWT 1 and 6MWT 2 were not statistically different for heart rate, distance, mean speed and blood pressure. Multiple r-squared (r2 = 0.96) explained 96% of the variation in the distance walked. Conclusion The use of 6MWT in artificial gait towards assessing exercise walking capacity is reproducible and easy to apply. It can be used to assess SCI artificial gait clinical performance.

The need for artificial tears in glaucoma patients: a comparative, retrospective study

PURPOSE: To evaluate the need for artificial tears by glaucoma patients under topical hypotensive treatment and to identify risk factors associated with it. METHODS: The charts of 175 glaucoma patients under medical treatment and 175 age-matched controls were reviewed. Age, gender, use of artificial tears, number of glaucoma medications used, and duration of treatment were recorded. RESULTS: Significantly more glaucoma patients (n=92; 52.6%) used artificial tears compared to age-matched controls (n=31; 17.7%) (p<0.001). Significantly more females (n=81; 39%) than males (n=42; 28.9%) used artificial tears (p=0.036). When the whole population was analyzed, female gender (OR=1.63) and the presence of glaucoma (OR= 5.14) were risk factors for the use of artificial tears (p<0.05). When the glaucoma population was analyzed, female gender (OR=2.57), number of medications >2 (OR=1.92), and duration of treatment >5 years (OR=2.93) were risk factors for the use of artificial tears (p<0.05). CONCLUSIONS: Topical treatment with antiglaucoma medication is a risk factor for the use of artificial tears. Female gender and long-term treatment of glaucoma with two or more medications were aggravating factors for the need for artificial tears.

Abrasion wear resistance of different artificial teeth opposed to metal and composite antagonists

One of the most important properties of artificial teeth is the abrasion wear resistance, which is determinant in the maintenance of the rehabilitation's occlusal pattern. OBJECTIVES: This in vitro study aims to evaluate the abrasion wear resistance of 7 brands of artificial teeth opposed to two types of antagonists. MATERIAL AND METHODS: Seven groups were prepared with 12 specimens each (BIOLUX & BL, TRILUX & TR, BLUE DENT & BD, BIOCLER & BC, POSTARIS & PO, ORTHOSIT & OR, GNATHOSTAR & GN), opposed to metallic (M & nickel-chromium alloy), and to composite antagonists (C & Solidex indirect composite). A mechanical loading device was used (240 cycles/min, 4 Hz speed, 10 mm antagonist course). Initial and final contours of each specimen were registered with aid of a profile projector (20x magnification). The linear difference between the two profiles was measured and the registered values were subjected to ANOVA and Tukey's test. RESULTS: Regarding the antagonists, only OR (M = 10.45 ± 1.42 µm and C = 2.77 ± 0.69 µm) and BC (M = 6.70 ± 1.37 µm and C = 4.48 ± 0.80 µm) presented statistically significant differences (p < 0.05). Best results were obtained with PO (C = 2.33 ± 0.91 µm and M = 1.78 ± 0.42 µm), followed by BL (C = 3.70 ± 1.32 µm and M = 3.70 ± 0.61 µm), statistically similar for both antagonists (p>0.05). Greater result variance was obtained with OR, which presented the worse results opposed to Ni-Cr (10.45 ± 1.42 µm), and results similar to the best ones against composite (2.77 ± 0.69 µm). CONCLUSIONS: Within the limitations of this study, it may be concluded that the antagonist material is a factor of major importance to be considered in the choice of the artificial teeth to be used in the prosthesis.