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This work aimed to study the technical feasibility of using industrial gypsum, expanded polystyrene (EPS), and cellulose solid wastes in the production of acoustic insulation panels for buildings. Five traces of acrylic gypsum matrix were produced with variations in the proportions of cellulosic pulp and EPS and always maintaining the same proportion of recycled gypsum and water. The composites produced were tested according to the ISO 10534-2 (2015) standard for the determination of the coefficient of sound absorption and ABNT NBR 14715-2 (2010) for bending tests. The results didn’t show statistically significant differences in the coefficient of sound absorption with variations in the quantities of each material. However, the sonic frequency of the tests directly influenced the results, presenting a better performance at a low frequency (250 Hz). The results qualify the composite produced for use as acoustic insulation and can be used in plates for sound reflection in buildings in places where it doesn’t require resistance to great stresses.

Made available in DSpace on 2020-12-12T02:16:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-02-01 This work physically, mechanically, and chemically characterized the composites produced from Portland CP II-E32 cement and fresh Indian cedar wood particles previously treated by immersion in hot and cold water. Density values for wood particulate composites were around 50% lower compared with the wood-free control treatment, from 0.88 to 1.78 g/cm. A larger swelling was observed for the composite material. The results of compressive strength and stiffness indicated that there is no need for particle treatment for composite production. Hot and cold water immersion treatments reduced the total Indian cedar wood extractives by 33% and 42%, respectively. Optical microscopy analysis was used to identify adhesion failures between the cement/wood interface of the composite produced with fresh particles, which presented a higher percentage of extractives. This result indicated that the greater concentration of total extractives partially inhibits the matrix-matrix interaction reinforcement. Despite the reduction in total extractives caused by the treatments, this process is not necessary for the composite production because there is no statistical difference between the treatments. The values obtained for the composite indicate the possibility of application in sealing blocks in light construction systems. Department of Mechanical Engineering UNESP-São Paulo State University, Avenida Ariberto Pereira da Cunha, 333 UNESP-São Paulo State University, Campus of Itapeva, Rua Geraldo Alckmin, 519 Department of Mechanical Engineering UNESP-São Paulo State University, Avenida Ariberto Pereira da Cunha, 333 UNESP-São Paulo State University, Campus of Itapeva, Rua Geraldo Alckmin, 519

Objective: To evaluate and compare the symptomatology and clinical findings in hyposecretory dry eye of the treatment with platelet‐rich plasma (PRP) and artificial tears of sodium hyaluronate (SH). Methods: Blind single‐centre prospective comparative randomized study including 83 patients with hyposecretory dry eye and mean age of 64.0 years. Two groups were differentiated depending on the treatment applied: 44 patients treated with PRP (PRP group), and 39 patients treated with artificial tears of SH (SH group). Changes in Schimer test, tear osmolarity, corneal and conjunctival staining, tear film break‐up time (TF‐BUT), conjunctival hyperaemia, dry eye‐related symptoms with the Ocular Surface Disease Index questionnaire, and caliciform cell density were evaluated during 30 days of treatment. Results: Significantly larger reduction in symptomatology (p < 0.001), visual improvement (p < 0.001), reduction in hyperaemia (p < 0.001), and corneal and conjunctival staining (p < 0.001), increment of Schirmer test outcome (p ≤ 0.005), and reduction of osmolarity were found in the PRP group in both eyes compared to SH group at 15 and 30 days of treatment. Likewise, a significantly higher increment of caliciform cell density (p < 0.001) was found in the PRP group. Strong and statistically significant correlations were found in the PRP group of the change achieved in visual acuity, hyperaemia, osmolarity, and conjunctival and corneal staining with the baseline values of these variables (p < 0.001). Conclusion: PRP treatment in hyposecretory dry eye induces a more significant positive effect over symptomatology and different dry eye signs than SH, especially in moderate and severe cases. The author David P Piñero has been supported by the Ministry of Economy, Industry and Competitiveness of Spain within the program Ramón y Cajal, RYC-2016-20471.

Wildland fire is a natural force that has shaped most vegetation types of the world. However, its inappropriate management during the last century has led to more frequent and catastrophic fires. Wildland fires are also recognized as one of the sources of CO2 and other greenhouse gases (GHG) that influence global climate change. As one of the techniques used to reduce the risk of destructive wildfires, prescribed burning has the potential of mitigating carbon emissions, and effectively contributes to the efforts proposed as part of the Clean Development Mechanism within the Kyoto protocol. In order to apply this concept to a real case, a simulation study was conducted in pine afforestation in the Andean region of Patagonia, Argentina, with the objective of evaluating the potential of prescribed burning for reducing GHG emissions. The scenario was established for a ten year period, in which simulated prescribed burning was compared to the traditional management scheme, which included the probability of annual average of wildfire occurrence based on available wildfire statistics. The two contrasting scenarios were: (1) managed afforestation, affected by the annual average rate of wildfires occurred in the same type of afforestation in the region, without prescribed burning, and (2) same as (1) but with the application of simulated prescribed burning. In order to estimate carbon stocks, and CO2 removals and emissions, we followed the guidelines given for GHG inventories on the Agriculture, Forestry and Other Land Uses (AFOLU) sector of the International Panel on Climate Change (IPCC), while the terminology used was the established by IPCC (2003). Data of afforested area, thinnings, and biomass growth were taken from previous surveys in the study area. Downed dead wood and litter (forest fuel load, FFL) was estimated adjusting equations fitted to those fuels, based on field data. Results show that comparing the two scenarios, prescribed burning reduced CO2 emissions by 44% compared to the situation without prescribed burning. The prescribed burning scenario represented about 12% of the total emissions (prescribed burning plus wildfires). Furthermore, avoided wildfires by simulated prescribed burning allowed an additional 78% GHG emissions mitigation due to extra biomass growth. Simulated prescribed burning in commercial afforestation of Patagonia appears to be an effective management practice not only to prevent wildfires, but also an efficient tool to mitigate GHG emissions. However, more studies in different scenarios would be needed to generalize these benefits to other ecosystems. Fil: Defossé, Guillermo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Loguercio, Gabriel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Oddi, Facundo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Freiburg University; Alemania Fil: Molina, Cristian Julio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Freiburg University; Alemania Fil: Kraus, Daniel. Freiburg University; Alemania