A madeira tem aplicações já difundidas em diversos setores, no entanto, muitas vezes é utilizada sem o conhecimento de suas propriedades. A caracterização de espécies de madeira consiste em determinar suas propriedades físicas, de resistência e rigidez através de ensaios normalizados. O inconveniente de grande parte desses ensaios é a utilização de equipamentos de alto custo e grande porte, disponíveis apenas em centros de pesquisa. Porém, o ensaio de densidade aparente é de fácil determinação por utilizar equipamentos simples na sua execução. Sendo assim, neste trabalho são determinadas as correlações entre a densidade aparente e as propriedades físicas, de resistência e de rigidez da madeira, de quarenta espécies nativas brasileiras, do grupo dicotiledôneas. Através de análise estatística, foram obtidas expressões matemáticas que permitem estimar, a partir da densidade aparente, grande parte das propriedades de resistência e rigidez da madeira. Tais expressões são apresentadas como proposta para a utilização na caracterização de espécies menos conhecidas, o que viabiliza o adequado emprego de espécies nativas nas mais variadas aplicações para as quais a madeira é indicada. Apresentam-se também aferições das expressões propostas pela norma brasileira NBR 7190, que permitem a caracterização simplificada das resistências da madeira de espécies usuais a partir dos ensaios de resistência à compressão paralela às fibras. / Wood has diffused applications in several sections, however, a lot of times it is used without the knowledge of its properties. The characterization of wood species consists of determining its physical, strength and stiffness properties, through normalized tests. The inconvenience of many of those tests is the use of equipments of high cost and great load, available just in research centers. Even so, the test of specific gravity is of easy determination for using simple equipments in its execution. Being like this, in this study the correlations between the specific gravity, physical and mechanical properties of wood from forty brazilian native species of hardwoods are determined. The mathematical expressions obtained through this study, permit estimate most wood properties of strength and stiffness, based on their specific gravity. Such expressions are proposed as means of characterizing less-known species, what makes possible the appropriate employment of native species in most varied applications for which wood is the indicated material. Furthermore, it is presented the calibration of the expressions proposed by the brazilian code NBR 7190, being these a simplified method of characterizing mechanical properties of common species of wood by means of tests of strength in compression parallel to the grain.

Dovetail joints are commonly seen in a furniture frame construction because of their unique configuration and strength. The tensile strength of dovetail joints was experimentally and analytically investigated using fracture mechanics method in this study. Experimental results of the investigation of effects of geometry factors on the tensile strength of dovetail joints in southern yellow pine and red oak indicated that the tensile strength of red oak joints was about 2 times higher than the one of southern yellow pine joints. Statistical analysis results indicated that the tail angle and tenon length of dovetail joints had significant influences on their tensile strength, and the tenon width was not a significant factor on the joint tensile strength. The fracture behaviors of southern yellow pine and red oak materials were investigated in the radial-longitudinal crack propagation system using a compact tension test method. Effects of wood specific gravity on fracture toughness for two wood species were studied in terms of their three growth ring combinations; earlywood, earlywood and latewood interface, and latewood. Regression analysis results indicated that the fracture toughness of two evaluated wood species can be predicted based on their specific gravity values. Statistical analyses indicated that the latewood yielded the significantly higher fracture toughness value, followed by earlywood and latewood interface, then earlywood for both wood species. Proposed prediction equations for tensile strengths of dovetail joints based on fracture toughness values of wooden materials used for frame construction were validated experimentally.

<p>The chemical and physical properties of nine samples of sodalite have been determined along with the physical properties of an additional thirteen samples. Taken together with selected data from the literature these data indicate that: (1) the cell dimension of sodalite is constant for samples from one deposit within the limits ascribed to experimental error (± 0.0015 A° ) and the variation of a(0) for samples from other deposits is quite limited (i.e. ±0.005 A° ); (2) the specific gravity and refractive index exhibit small but measurable variations which cannot however be related to compositional variation; (3) the variation in chemical composition for sodalite indicated by analyses from the literature appears to be in error; much of the variation is attributed to zeolite impurities which were not removed from the samples before analysis; (4) probably all sodalites are represented to within 5 per cent by 6Na AlSiO(4).2NaCl with less than 0.30 weight per cent H(2)O.</p> <p>A petrographic study of the sodalite deposit at the Princess Quarry, Bancroft, Ontario, indicates that this mineral has formed from the reaction of chlorine-rich solutions with nepheline. The solutions appear to be derived from granite and syenite bodies which are regionally abundant in the vicinity of the Bancroft band of nepheline syenite gneiss. Many facts suggest that the present veins in the quarry have formed by the replacement of a pre-existing nepheline pegmatite.</p> / Thesis / Master of Science (MSc)

Over the last 50 years significant advancements have been made in the southern yellow pine (SYP) forests in the U.S. south. Due to silvicultural changes and large scale reforestation efforts the US south has seen significant increases in standing volume (more than 120% over the period). Landowners that grow SYP plantations largely manage for trees that are harvested to produce dimensional lumber. With the changes in growth patterns it is of interest if there have been any changes in structural properties of the lumber that is produced from timber grown today. Landowners desire confirmation that what they are doing in terms of management is maintaining the quality and strength of lumber that the market demands. This information is critical because timberland owners’ plant and manage trees that will ultimately be brought to market at lumber 25-40 years into the future. In an effort to provide clarity to this topic this dissertation investigates: 1) The extent to which the specific gravity (SG), bending strength (modulus of rupture, MOR), and bending stiffness (modulus of elasticity, MOE) of small clear specimens of SYP have changed, particularly with respect to reduction(s), during the interval from approximately 1965 to 2015. 2) The extent to which the compression parallel to grain and perpendicular to grain strength of small clear specimens of SYP have changed, particularly with respect to reduction(s), during the interval from approximately 1965 to 2015. Use statistical analysis of variance to investigate potential differences among data from a historical 1966 data set, a 2014 in-grade data set, and a 2018 staircase material data set. 3) The nature of the relationship between and among SG, MOE, and MOR of small clear specimens of SYP and how these relationships may have changed, during the interval from approximately 1965 to 2015. Use statistical regression analysis to explore changes to the interrelationships of SG, MOE, and MOR among the three samples, with particular interest toward how these may impact or influence non-destructive evaluation. This work consists of 3 independent chapters using varying appropriate statistical methods and is accompanied by an introduction and conclusion.

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An appropriate accounting for thinning effects on growth rate and wood quality requires a clear understanding and quantification of these effects. In this regard, four basic interrelated issues were addressed in this study: 1) thinning effects on ring specific gravity 2) thinning effects on ring width distribution 3) thinning effects on stem form, and 4) prediction models for these quantities. The study showed that thinning does not significantly affect ring specific gravity, whereas its effects on ring width distribution and stem form were significant. Thinning increases ring width significantly over most of the tree bole and increases the earlywood and latewood components proportionally maintaining an approximately constant latewood proportion. As a consequence, thinning effects on latewood proportion is not significant; confirming the results obtained in the specific gravity study and further dispelling the concern that thinning may substantially reduce wood specific gravity. Thinning affects stem form by increasing the form exponent especially near the tree base accentuating the neiloid form expected in that area. High up in the stem, the form exponent changes little within a tree and among thinning treatments, with a general tendency towards a paraboloid shape. Differences due to thinning intensities, in general, were not significant indicating the applicability of results within a wide range of densities. Prediction models for ring specific gravity, ring width, latewood proportion and stem profile based on ring, tree, stand and site factors were developed Influences of stand level factors, density measures in particular, in prediction models are minor probably because tree level factors such as, stem diameter at breast height, crown ratio, etc. themselves manifest stand conditions. The mixed-effects analysis technique was used in data analysis to account for correlation among observations from the same subject. Direct covariance modeling yielded better fits than accounting for correlation indirectly using random effects covariates in many cases; however, both could not be accommodated simultaneously. Structures which assume decreasing correlation with increasing distance between observations, such as the first-order autoregressive structure, performed better than alternative specifications. Results consistently showed that accounting for correlation among observations substantially improves the fits over ignoring correlation; effectively addressing the issue of bias in the standard errors of estimates. / Ph. D.

Adequate hydration is critical for optimal performance and health. Fluid requirements of collegiate athletes are unique due to training and competition, travel, school schedules, and stressors common in college environments. Inattention to these factors may contribute to suboptimal hydration. Importantly, loss of 1-2% of body weight by dehydration can impair physical and cognitive performance. As such, development of valid and reliable tools to assess hydration status in collegiate athletes is needed. The purpose of this study was to assess the validity of urine color (UC) as a measure of hydration status in collegiate athletes. A secondary purpose was to evaluate the utility of indexes of hydration status for UC and urine specific gravity (USG) established by the American College of Sports Medicine (ACSM) and the National Athletic Trainers' Association (NATA). To address this, 62 NCAA Division I collegiate athletes provided a urine sample ≤30 minutes of exercise for UC self-assessment (UCsub) and experimenter-assessment (UCres) using the UC chart developed by Armstrong et al. (1994) and for USG measurement via refractometry (1). Habitual dietary intake was assessed by 24-hr recalls. There was a significant positive correlation between USG and both UCsub (r=0.679, p<0.001) and UCres (r=0.772, p<0.001). In addition, the USG based on UC was inconsistent with hydration/dehydration categories established by ACSM and NATA. These findings suggest that UC, even when self-assessed by the athlete, is a valid method for assessing hydration status in NCAA division I college athletes. However, some modification of ACSM and NATA hydration categories may be warranted. 1. Armstrong LE, Maresh CM, Castellani JW, et al. Urinary indices of hydration status. Int J Sport Nutr. 1994;4(3):265-279. http://www.ncbi.nlm.nih.gov/pubmed/7987361. Accessed October 26, 2016. / Master of Science / Staying well hydrated is important for athletes’ health and to help them perform at their best. College athletes fluid needs are unique because of their training and competition schedules, class schedules, frequent travel, and emotional stress that is common for college students. Without conscious efforts to consume enough fluid during the day, athletes may not be well hydrated. Small decreases in body weight from dehydration can result in negative consequences for physical and mental performance. This is why it is important to develop tools that can accurately and consistently determine how hydrated athletes are. The purpose of this study was to see if urine color could accurately determine if college athletes were well hydrated or dehydrated. Also, the usefulness of hydration categories for urine color and urine specific gravity (USG) from the American College of Sports Medicine (ACSM) and the National Athletic Trainers’ Association (NATA) were tested. Our study recruited 62 NCAA Division I college athletes. Participants provided a urine sample where researchers and participants determined the urine color of the sample based on a urine color chart and USG was measured (1). In addition, a list of all foods and beverage consumed by participants were recorded for three days. Our correlational analysis suggest that UC, even when self-assessed by the athlete, can accurately determine if NCAA division I college athletes are well-hydrated or not. In addition, our results suggest that some modification made be needed to the ACSM and NATA hydration categories.

abstract: Exposure to sun radiation (SUR) with ambient temperature may be an influencer on athletes’ sweat loss in different environments, but the results are not currently known. The purpose of this study was to determine the effects of SUR on fluid balance (FB) and hydration status (HS) in athletes exercising indoors and outdoors. Initial FB and HS were assessed in NCAA-DI female soccer athletes (n=10) of a single team in temperate, dry conditions (55-68°F, 18-48% humidity) who were monitored during 3 practices of equal estimated energy expenditure (EE): two outdoors in direct SUR (cold/moderate temperatures) and one indoors without SUR (moderate temperatures). Humidity, temperature, and wet bulb globe temperature (WBGT – a measurement partly based on SUR, including ambient temperature/relative humidity) were recorded using Heat Stress Meters placed in the direct sun or in the shade. Each athlete’s semi-nude dry body weight was recorded before and after exercise. Urine samples were taken before, after, and the morning after. Urine specific gravity (USG) was tested to assess HS. Athletes wore combined heart rate and activity monitors to estimate EE and were provided ad libitum water and/or a zero-calorie sports drink. Their total intake included weights of consumed food and drink. Sweat rate was calculated using body weight change and intakes of liquids minus urine losses/hour. Two-way repeated measures ANOVA analyzed group-level differences. No significance was found in total FB (1.01±0.32 L/hr) or EE/hr (444±97.1 kcal/hr) across all days (p>0.05). In analyzing individual athlete results, 40% had consistent USG >1.025 (p=0.001) suggesting potential dehydration. These 4 athletes selected water as their beverage, of which is known that consuming only water does not stimulate drinking behavior as does electrolyte drinks. The remaining 60% were overall not dehydrated (USG <1.025) but must be aware of incidental dehydration in hotter temperatures. The conclusion is that in low-moderate temperatures, athletes self-regulate drinking habits and achieve fluid balance during exercise with or without sun radiation. However, athletes with average USG >1.025 are likely to remain dehydrated in moderate temperatures. The findings suggest that more education would benefit these athletes by ensuring hydration in any environment. / Dissertation/Thesis / Masters Thesis Nutrition 2019

Recycled Asphalt Pavement (RAP) is the largest recycled good in the United States and 80 million tons are recycled yearly, saving taxpayers about $1.5 billion dollars. This paper explores the possibility of utilizing 100% RAP materials in asphalt pavement. Asphalt mixtures are produced at 135°C in a typical asphalt plant. However, at 135°C, not all binder from RAP materials may not become effective for coating aggregates. The main objective of the study is to determine the amount of effective binder available from RAP in the asphalt plant. The 100% RAP mixes have aged binder that can alter mix designs and interaction with virgin binder. In this study, to determine low temperature cracking resistance and fatigue performance, samples were prepared using a 100% RAP mix with no virgin binder and a 100% RAP mix with virgin asphalt binder to achieve the optimum binder content of the mix. Second, to determine the effectiveness of binder from RAP materials, compaction tests were performed by heating RAP materials at various temperatures. It was found that 100% RAP mixes cannot be feasible for field use if additional virgin binder is added to reach the optimum asphalt content. Based on limited test results, the low temperature grade was not within proper limits but the beam fatigue testing results were acceptable. Based on compaction test results, additional heating is needed to increase the effectiveness of asphalt binder from RAP materials.

The reproductive success for pelagic spawning Baltic flounders is strongly linked to the hydrodynamics in the spawning areas. Egg survival is dependent upon the ability to achieve neutral buoyancy at a depth interval where temperature and oxygen concentrations are favourable for egg development. The main focus of this thesis was to compare egg survival probabilities of pelagic eggs from Baltic flounder in the Bornholm, Gdansk and Gotland basins, prior to and after the saline water inflow in December 2014. The results showed greatly enhanced survival probabilities in Bornholm basin 2015 (p&lt;0.01), as egg survival increased from 47% in 2014 to 100% the following year. In Gdansk basin the situation was similar, and survival probability increased from 13% to 100% (p&lt;0.01). In Gotland basin no difference in survival probability was identified, although the dominant cause of mortality shifted from sedimentation, i.e. due to low salinity conditions in 2014, to oxygen deficiency in 2015 (p&lt;0,01). / BONUS INSPIRE-project, the joint Baltic Sea research and development programme (Art 185), funded jointly by the European Union’s Seventh Programme for research, technological development and demonstration and the Swedish Research Council Formas