In situ acoustic methods to estimate the physical and mechanical aging of oriented strand board

Following the success achieved in previous research projects usin non-destructive methods to estimate the physical and mechanical aging of particle and fibre boards, this paper studies the relationships between aging, physical and mechanical changes, using non-destructive measurements of oriented strand board (OSB). 184 pieces of OSB board from a French source were tested to analyze its actual physical and mechanical properties. The same properties were estimated using acoustic non-destructive methods (ultrasound and stress wave velocity) during a physical laboratory aging test. Measurements were recorded of propagation wave velocity with the sensors aligned, edge to edge, and forming an angle of 45 degrees, with both sensors on the same face of the board. This is because aligned measures are not possible on site. The velocity results are always higher in 45 degree measurements. Given the results of statistical analysis, it can be concluded that there is a strong relationship between acoustic measurements and the decline in physical and mechanical properties of the panels due to aging. The authors propose several models to estimate the physical and mechanical properties of board, as well as their degree of aging. The best results are obtained using ultrasound, although the difference in comparison with the stress wave method is not very significant. A reliable prediction of the degree of deterioration (aging) of board is presented.

Researching in ancient engineering physical and chemical analysis in hidraulic roman mortars

Around ten years ago investigation of technical and material construction in Ancient Roma has advanced in favour to obtain positive results. This process has been directed to obtaining some dates based in chemical composition, also action and reaction of materials against meteorological assaults or post depositional displacements. Plenty of these dates should be interpreted as a result of deterioration and damage in concrete material made in one landscape with some kind of meteorological characteristics. Concrete mixture like calcium and gypsum mortars should be analysed in laboratory test programs, and not only with descriptions based in reference books of Strabo, Pliny the Elder or Vitruvius. Roman manufacture was determined by weather condition, landscape, natural resources and of course, economic situation of the owner. In any case we must research the work in every facts of construction. On the one hand, thanks to chemical techniques like X-ray diffraction and Optical microscopy, we could know the granular disposition of mixture. On the other hand if we develop physical and mechanical techniques like compressive strength, capillary absorption on contact or water behaviour, we could know the reactions in binder and aggregates against weather effects. However we must be capable of interpret these results. Last year many analyses developed in archaeological sites in Spain has contributed to obtain different point of view, so has provide new dates to manage one method to continue the investigation of roman mortars. If we developed chemical and physical analysis in roman mortars at the same time, and we are capable to interpret the construction and the resources used, we achieve to understand the process of construction, the date and also the way of restoration in future.

Some physical and chemical proceddes in fluids

The ability to reproduce reduced gravity conditions for long periods is one of the reasons why the orbiting laboratory is so attractive. In this paper several fluid dynamics problem areas are reviewed in which zero-gravity conditions are of great importance. Although emphasis is placed on space processing, there are some older problems also in which gravity masks the phenomcna, impeding a reasonably simple approach to the solution. Three problems are considered: Thermal convection under reduced gravity. The dumping effect ofsurface gravity waves at the outset of convection induced by surface tractions is discussed in particular. The existence of convection is of concern for some satellite thermal control techniques presently used, and for most of the proposed manufacturing processes. Whereas convection should be normally avoided, problems related to the containerless stirring ofa melt constitute an exception. Secondly, gravity and chemical reactions. Although chemical reactions are independent of gravity because of the small mass of the molecules and atoms involved, in many cases the reaction rate dcpends on the arrival of the species to the reaction zone. When the arrival process is buoyancy-controlled, the net specd of the reaction will be affected by the gravity. Thirdly, two-phase flows under reduced gravity provkle interesting problems from boiling heat transfer to degasslng of melts. This part of the paper deals only with the measurement of sound veiocity in a liquid containing bubbles. It is suggested that such measurements should be mude under reduced gravity to provide reliable residís.

Physical and mathematical modeling of wave propagation in the Ariane 5 VEB structure

The separation of the lower stage of the ARIANE 5 Vehicle Equipment Bay (VEB) Structure is to be done using a pyrotechnic device. The wave propagation effects produced by the explosion can affect the electronic equipment, so it was decided to analyze, using both physical and numerical modeling, a small piece of the structure to determine the distribution of the accelerations and the relative importance of damping, stiffness, connections, etc. on the response of the equipment.

Effects of soil management in vineyard on soil physical and chemical characteristics

Cover crops in Mediterranean vineyards are scarcely used due to water competition between the cover crop and the grapevine; however, bare soil management through tillage or herbicides tends to have negative effects on the soil over time (organic matter decrease, soil structure and soil fertility degradation, compaction, etc). The objective of this study was to understand how soil management affects soil fertility, compaction and infiltration over time. To this end, two bare soil techniques were compared, tillage (TT) and total herbicide (HT) with two cover crops; annual cereal (CT) and annual grass (AGT), established for 8 years. CT treatment showed the highest organic matter content, having the biggest amount of biomass incorporated into the soil. The annual adventitious vegetation in TT treatment (568 kg dry matter ha-1) that was incorporated into the soil, kept the organic matter content higher than HT levels and close to AGT level, in spite of the greater aboveground annual biomass production of this treatment (3632 kg dry matter ha-1) whereas only its roots were incorporated into the soil. TT presented the highest bulk density under the tractor track lines and a greatest resistance to penetration (at 0.2 m depth). AGT presented bulk density values (upper 0.4 m) lower than TT and penetration resistance in CT lower (at 0.20 m depth) than TT too. Effects of soil management in vineyard on soil physical and chemical characteristics - ResearchGate. Available from: http://www.researchgate.net/publication/268520480_Effects_of_soil_management_in_vineyard_on_soil_physical_and_chemical_characteristics [accessed May 20, 2015].

Physical and functional association of glycolipid N-acetyl-galactosaminyl and galactosyl transferases in the Golgi apparatus

Glycolipid glycosyltransferases catalyze the stepwise transfer of monosaccharides from sugar nucleotides to proper glycolipid acceptors. They are Golgi resident proteins that colocalize functionally in the organelle, but their intimate relationships are not known. Here, we show that the sequentially acting UDP-GalNAc:lactosylceramide/GM3/GD3 β-1,4-N-acetyl-galactosaminyltransferase and the UDP-Gal:GA2/GM2/GD2 β-1,3-galactosyltransferase associate physically in the distal Golgi. Immunoprecipitation of the respective epitope-tagged versions expressed in transfected CHO-K1 cells resulted in their mutual coimmunoprecipitation. The immunocomplexes efficiently catalyze the two transfer steps leading to the synthesis of GM1 from exogenous GM3 in the presence of UDP-GalNAc and UDP-Gal. The N-terminal domains (cytosolic tail, transmembrane domain, and few amino acids of the stem region) of both enzymes are involved in the interaction because (i) they reproduce the coimmunoprecipitation behavior of the full-length enzymes, (ii) they compete with the full-length counterpart in both coimmunoprecipitation and GM1 synthesis experiments, and (iii) fused to the cyan and yellow fluorescent proteins, they localize these proteins to the Golgi membranes in an association close enough as to allow fluorescence resonance energy transfer between them. We suggest that these associations may improve the efficiency of glycolipid synthesis by channeling the intermediates from the position of product to the position of acceptor along the transfer steps.

Physical and functional interactions between Drosophila TRAF2 and Pelle kinase contribute to Dorsal activation

Signaling through the Toll receptor is required for dorsal/ventral polarity in Drosophila embryos, and also plays an evolutionarily conserved role in the immune response. Upon ligand binding, Toll appears to multimerize and activate the associated kinase, Pelle. However, the immediate downstream targets of Pelle have not been identified. Here we show that Drosophila tumor necrosis factor receptor-associated factor 2 (dTRAF2), a homologue of human TRAF6, physically and functionally interacts with Pelle, and is phosphorylated by Pelle in vitro. Importantly, dTRAF2 and Pelle cooperate to activate Dorsal synergistically in cotransfected Schneider cells. Deletion of the C-terminal TRAF domain of dTRAF2 enhances Dorsal activation, perhaps reflecting the much stronger interaction of the mutant protein with phosphorylated, active Pelle. Taken together, our results indicate that Pelle and dTRAF2 physically and functionally interact, and that the TRAF domain acts as a regulator of this interaction. dTRAF2 thus appears to be a downstream target of Pelle. We discuss these results in the context of Toll signaling in flies and mammals.

The physical and genomic organization of microsatellites in sugar beet.

Microsatellites, tandem arrays of short (2-5 bp) nucleotide motifs, are present in high numbers in most eukaryotic genomes. We have characterized the physical distribution of microsatellites on chromosomes of sugar beet (Beta vulgaris L.). Each microsatellite sequence shows a characteristic genomic distribution and motif-dependent dispersion, with site-specific amplification on one to seven pairs of centromeres or intercalary chromosomal regions and weaker, dispersed hybridization along chromosomes. Exclusion of some microsatellites from 18S-5.8S-25S rRNA gene sites, centromeres, and intercalary sites was observed. In-gel and in situ hybridization patterns are correlated, with highly repeated restriction fragments indicating major centromeric sites of microsatellite arrays. The results have implications for genome evolution and the suitability of particular microsatellite markers for genetic mapping and genome analysis.

Physical and functional independency of p70 and p58 natural killer (NK) cell receptors for HLA class I: their role in the definition of different groups of alloreactive NK cell clones.

Natural killer (NK) cells express clonally distributed receptors for different groups of HLA class I alleles. The Z27 monoclonal antibody described in this study recognizes a p70 receptor specific for HLA-B alleles belonging to the Bw4 supertypic specificity. Single amino acid substitutions in the peptide-binding groove of HLA-B2705 molecules influenced the recognition by some, but not all, p7O/Z27+ clones. This suggests the existence of a limited polymorphism within the p7O family of receptors. The pattern of reactivity of monoclonal antibody Z27 revealed that Bw4-specific receptors may be expressed alone or in combination with different (GL183 and/or EB6) p58 molecules. Analysis of NK clones coexpressing p58 and p7O receptors allowed us to demonstrate that the two molecules represent physically and functionally independent receptors. The expression of p7O molecules either alone or in combination with EB6 molecules provided the molecular basis for understanding the cytolytic pattern of two previously defined groups of "alloreactive" NK cell clones ("group 3" and "group 5").

Processing of speech signals for physical and sensory disabilities.

Assistive technology involving voice communication is used primarily by people who are deaf, hard of hearing, or who have speech and/or language disabilities. It is also used to a lesser extent by people with visual or motor disabilities. A very wide range of devices has been developed for people with hearing loss. These devices can be categorized not only by the modality of stimulation [i.e., auditory, visual, tactile, or direct electrical stimulation of the auditory nerve (auditory-neural)] but also in terms of the degree of speech processing that is used. At least four such categories can be distinguished: assistive devices (a) that are not designed specifically for speech, (b) that take the average characteristics of speech into account, (c) that process articulatory or phonetic characteristics of speech, and (d) that embody some degree of automatic speech recognition. Assistive devices for people with speech and/or language disabilities typically involve some form of speech synthesis or symbol generation for severe forms of language disability. Speech synthesis is also used in text-to-speech systems for sightless persons. Other applications of assistive technology involving voice communication include voice control of wheelchairs and other devices for people with mobility disabilities.

Bioactive compounds and physical and chemical characteristics of mini tomatoes: influence of postharvest treatments

Tomatoes are among the most cultivated and used vegetables in the world. They are very succeptible to post harvest losses due to high perishability, therefore the use of postharvest treatments may contribute to conservation of this fruit, however the treatments might affect significantly physico-chemical, sensory and nutritional characteristics of tomatoes. Given the perishability of tomato and the economic importance of small tomato fruits, the purpose of the present study was to determine the effect of gamma radiation, carnauba coating and 1-MCP treatments on tomato fruit quality during storage. The study may be divided into two parts. In the first, mini tomatoes cv. Sweet Grape were harvested at breaker stage, divided into 4 grous and treated with gamma radiation (0.6 kGy), carnauba coating (1 L 1000 kg-1) and 1-MCP (500 nL L-1) and then stored at 25±2°C for 30 days with a control group of tomatoes. In the seconnd part, tomatoes harvested at light-red stage were submitted to the same treatments and storage period. Every 6 days tomatoes were evaluated for color modifications, fruit firmness, souble and total pectin (only for light-red tomatoes), mass loss, titratable acidity (TA), soluble solids (SS), SS/TA ratio, carotenoids profile, formation of lycopene isomers, total phenolic compounds, ascorbic acid and antioxidant capacity. For tomatoes harvested at breaker stage and submitted to the treatments the results showed mass loss was delaying mainly by carnauba wax, and to a lesser extend by 1-MCP. Fruit firmness were better retained for 1-MCP treated fruits and carnauba treatment showed a transient effect in preserving fruit firmness. SS/TA of tomatoes treated with gamma radiation and carnauba presented no differences from control values, and were lower with the application of 1-MCP. Color was negatively affected by 1-MCP and earlier changed (6th day) when gamma radiation was applied. In relation to bioactive compounds of tomatoes harvest at breaker stage, results indicated gamma radiation and 1-MCP decreased the final content of lycopene and produced more (Z)-isomers of lycopene. Gamma radiation also induced a decreased in ?-carotene and an increased in phenolic compounds by the end of storage period. 1-MCP treatment promoted a slow down increase in ascorbic acid content during storage. Antioxidant capacity of the hydrophilic fraction was not dramatically affected by treatments and the lipophilic fraction was lower, especially for 1-MCP fruits. In addition, contents of ?-carotene, lycopene, (Z)-isomers of lycopene, ascorbic acid and antioxidant capacity increased during the period of storage while contents of lutein and phenolic compounds tended to decrease. Regarding tomatoes harvest at light-red stage, the most effective treatments for delaying fruit firmness and mass loss was carnauba and 1-MCP, while gamma radiation was the treatment with higher mass loss and the less fruit firmness, which could be associated with the higher solubilization of pectins promoted by radiation treatment. Color (L* and Hue) was mainly affected by 1-MCP treatment which delayed color development, however, by the end of storage, the values were not different from the other treatments. SS/TA ratio was lower for fruits treated with 1-MCP and TA was not so dramatically affected by treatments. Furthermore, mini tomatoes harvested at light-red stage, demonstrated irradiation induced changes in the final content of lycopene, increasing it, and formed less (13Z)-lycopene, while 1-MCP and carnauba coating slow down the increase in lycopene and slown down the decrease of ascorbic acid and phenolic compounds. Antioxidant capacity of lipophilic fraction was not affected by treatments and the hydrophilic fraction was lower for irradiated fruits only on day 0 as well as phenolic compounds. In the other days, no differences among treatments were observed for hydrophilic antioxidant capacity. Considering the results, the best combination of SS and TA and fruit preservation for mini tomatoes harvest at breaker stage was promoted by carnauba coating, which seems to be the treatment that causes fewer changes in bioactive compounds of breaker tomatoes. However, when mini tomatoes were harvested at light-red stage, SS/TA ratio and color were better and, to preserve the quality of these fruits, besides carnauba coating, 1-MCP also could be indicated

A Physical and Social Study of Mountain Bike Use on Five Segments of the Continental Divide National Scenic Trail in Colorado

This capstone reviews uses of the Continental Divide National Scenic Trail. Policies governing use of the trail appear to be ambiguous, especially regarding mountain bicycles. Mountain biking has grown since the trail was created, but is not fully addressed in existing or proposed policy. 382 people on five segments of the trail in Colorado were interviewed for this capstone. Mountain bikes, hiking, and motorized recreation were observed uses. User conflict, overcrowding, degraded recreation experiences, or user displacement was not reported. User satisfaction was high and most would return. Interviewees requested increased public involvement and recognition of user needs in setting policy. Trail degradation occurs, but is unassociated with any particular use. Recommendations for trail improvement and maintenance are presented.

Fire-resistance, physical, and mechanical characterization of particleboard containing Oceanic Posidonia waste

In this work, particleboards manufactured with Oceanic Posidonia waste and bonded with cement are investigated. The particleboards are made with 3/1.5/0.5 parts of cement per part of Posidonia waste. The physical properties of bulk density, swelling, surface absorption, and dimensional changes due to relative humidity as well as the mechanical properties of modulus of elasticity, bending strength, surface soundness, perpendicular tensile strength and impact resistance are studied. In terms of the above properties, the best results were obtained for particleboards with high cement content and when the waste “leaves” are treated (crushed) before board fabrication, due to internal changes to the board structure under these conditions. Based on the results of fire tests, the particleboard is non-flammable without any fire-resistant treatment.