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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Nutritional Profile of Native Warm-Season Grass Grown as a Mono- or Multi-Species Pasture

Oloyede, Babatunde 11 May 2013 (has links)
The objective of this study was to evaluate the nutritional profile of mono- or multi-species pastures of native warm season grasses. One of four treatments were randomly assigned to Twelve pastures: 1) BG; 2) IG; 3) Mix G; 4) Mix NG. Growing steers (n = 225) were randomly assigned to one of nine pastures. Grass samples were taken from all pastures every 28 days during a four-month period and were analyzed for nutrient composition. Bermudagrass pastures had greater crude protein and ADF, but less NDF concentrations compared with the native warm-season grasses. Crude protein, IVDMD, and NDF IVDMD concentration decreased while NDF, ADF, and Hemicellulose concentration increased as grasses matured. Steers grazing IG and Mix G pastures gained more weight and consumed more forage than those on BG pastures. It appears that native warm-season grasses may offer a viable alternative to BG for grazing cattle during the summer.
62

Effects Of Warm-Ups On Time Trials For Elite Ncaa Division I 800-Meter Middle Distance Runners: Establishing A Priming Warm-Up For Optimum Results In A Peak Performance

Keesling, Roger Lynn 09 May 2015 (has links)
This study utilized an experimental design testing low, medium, and high intensity warm-up protocols for NCAA Division I 800-meter male and female middle distance runners to determine which result in optimal outcomes in a peak performance, i.e., 800-meter time trial. Mississippi State University student athletes on the Track and Field Team who compete in middle distance running events participated. Among males, results of the repeated measures ANOVA found no significant difference among the three warm-up protocols for the first 400 meters completed. For females, repeated measures ANOVA results found no significant difference among the protocols for the first 200 meters completed. However, at the completion of the 800-meter time trial, a statistically significant difference (p < 0.05) was seen among both males and females; post hoc analyses indicated that the high intensity warm-up group had a statistically significantly lower (i.e., better) total time than the low intensity warm-up group.
63

Isolated or Coupled Oxidative, Moisture, and Freeze-Thaw Effects on Warm Mix Asphalt

Pittman, Carl 10 August 2018 (has links)
This thesis aims to contribute to the growing body of warm mix asphalt (WMA) research by evaluating the differences in behavioral properties of three WMA mixtures, representing the three warm mix technology (WMT) categories (foaming, chemical additives, and organic waxes), relative to a control hot mix asphalt (HMA) in a specific set of conditions which is not well documented in literature. These conditions are: plant produced mixtures with all virgin aggregates and binder (i.e. no recycled materials) and no additives other than the warm mix technology. These mixtures were evaluated at low, intermediate, and high testing temperatures before and after a set of conditioning protocols (CPs), which utilized varying levels of isolated and combined oxidative, moisture, and freeze-thaw damage. A key feature of this thesis is that damage induced by these CPs has been benchmarked relative to measured field aging effects through studies which evaluated the three WMA mixtures and one HMA mixture used to obtain the results presented here, along with additional mixtures not considered in this thesis.
64

The effect of temperature on the physical properties of bioceramic sealers

Khoshnoodi, Alireza 22 June 2023 (has links)
INTRODUCTION: The compatibility of EndoSequence BC Sealer (BC Sealer; Brasseler USA, Savannah, GA) for warm vertical compaction has been questioned due to changing physical properties under higher temperature. The aim was to evaluate the effect of heating on the physical properties (flowability and radiopacity) of a new calcium-based root canal sealer (EndoSequence BC Sealer HiFlow [HiFlow]) in comparison with EndoSequence BC Sealer. METHODS: The flow, and radiopacity of the 2 sealers were measured according to ISO 6786/2012 at different temperatures. Forty real printed plastic teeth (incisor) were used to evaluate the flowability of the two Standard EndoSequence BC Sealer and HiFlow EndoSequence BC Sealer into the lateral and apical accessory canals. These evaluation was done with two obturation techniques including single cone and warm vertical condensation. RESULT: The mean flowability was ranging from 22.25 mm to 9.52 mm. The results indicate that there is a statistical difference between the flowability of the two calcium silicate based sealers under all three different temperatures (37˚C, 100˚C and 150˚C). Radiopacity was measured at two different temperatures including 21˚C and 100˚C. The mean gray value ranged from 213.55 to 202.25. Results showed that HiFlow is more radiopaque and there is a statistically significant difference at both temperatures. The results of single cone and warm vertical obturation techniques show that there is no significant difference between the flowability of the two calcium silicate based sealers into the lateral and apical accessory canals at 21°C and there is a significant difference at higher temperatures. CONCLUSIONS: HiFlow BC sealer had higher flow and was more radiopaque, especially at high temperatures, which are generated by the commonly used warm vertical compaction technique.
65

Performance Assessment Of Warm Mix Asphalt (WMA) Pavements

Al-Rawashdeh, Abdalla S. 19 December 2008 (has links)
No description available.
66

Responses to warm versus cool landscape colors

Heeter, Sarah Ann 10 October 2005 (has links)
No description available.
67

Hydroforming of tubular materials at various temperatures

Aue-u-lan, Yingyot 05 January 2007 (has links)
No description available.
68

Can Beef Be Bee-Friendly?  Using Native Warm-Season Grasses and Wildflowers in Pastures to Conserve Bees

Wagner, Jennie Faith 29 May 2020 (has links)
Over the past several decades, native and managed bee populations have decreased in the United States and worldwide. Although bee decline is attributable to several factors, habitat loss is the primary driver. Simultaneously, cattle producers in the eastern U.S. rely primarily on cool-season forages that peak in biomass production in late spring, leading to a lack of forage in the summer months and increasing the costs of cattle production. Seeding pastures with a mix of native warm-season grasses and native wildflowers could increase forage availability while also increasing available resources for bees. In this study, a mix of three native warm-season grasses (NWSGs) and 15 wildflower species was planted at the Virginia Tech Shenandoah Valley Agricultural Research and Extension Center (SVAREC). The objectives of this project were to document the establishment and species composition of NWSG + wildflower pasture mixtures, compare the attractiveness of wildflowers and weedy species to bees, and compare the bee community between NWSG + wildflower pastures and more typical cool-season grass pastures. The wildflowers in the NWSG + wildflower pastures dominated over grasses. All wildflower species that established were attractive to bees, as were some weedy species. The NWSG + wildflower treatments had the highest abundance of bees collected, with an average of 14.8 bees collected per pasture per sampling date in 2018, and an average of 12.4 bees collected per pasture per sampling date in 2019. These results indicate that with modification of establishment methods so that more grasses are present, this pasture system could be beneficial from both a cattle production and bee conservation standpoint. / Master of Science in Life Sciences / Over the past several decades, there has been a decline in bee populations in the U.S. and around the world. Bees play an important role in pollinating many food crops, including most fruits and vegetables. Habitat loss is the biggest contributor to their decline. There are also issues with cattle production in the eastern U.S. Most farmers rely on grasses that are the most productive in the late spring and early summer, meaning that by mid- and late summer, there is little grass available for cattle. Planting pastures with native grasses designed to be the most productive in the late summer and native wildflowers could increase food available for cattle as well as provide more pollen and nectar for bees. In this experiment, we planted a mix of three grasses and 15 wildflowers. We documented how well the grasses and wildflowers established. We also examined how attractive wildflowers and weeds were to bees and compared the number and types of bees collected between the new pastures and traditional pastures. We found that the wildflowers, instead of the grasses, dominated the pastures. All wildflowers that established, as well as some weeds, attracted bees and provided resources. Higher numbers of bees were collected in the pastures with wildflowers than standard grass pastures, but there were not necessarily more bee species present. These results suggest that, with some modifications, planting native grasses and wildflowers in pastures could help conserve bees as well as benefit cattle farmers.
69

AvaliaÃÃo do desempenho de misturas asfÃlticas recicladas mornas em laboratÃrio e em campo / Evaluation of Warm Mixture Asphalt with RAP Performance in the Laboratory and in the Field

Jardel Andrade de Oliveira 28 November 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A pavimentaÃÃo utiliza grandes volumes de recursos naturais requerendo aÃÃes que mitiguem os consequentes danos ambientais. Observando-se uma obra rodoviÃria, pode-se destacar aspectos que afetam o meio ambiente, como: desmatamento, extrativismo mineral para a produÃÃo de agregados e extraÃÃo e refino de petrÃleo para utilizaÃÃo em camadas asfÃlticas. Esta atividade faz uso ainda de processos que geram grandes volumes de passivos ambientais, tais como: fresagem e demoliÃÃes. O material fresado pode ser reciclado e reaproveitado, por exemplo, na produÃÃo de Misturas AsfÃlticas Recicladas a Quente (MARQs). As altas temperaturas que as misturas asfÃlticas exigem para tornarem-se trabalhÃveis submetem o ambiente a sua volta, especialmente os operÃrios que trabalham na produÃÃo do revestimento asfÃltico na usina, à condiÃÃes insalubres. Tendo em vista que o Cimento AsfÃltico de PetrÃleo (CAP), quando submetido a altas temperaturas, libera fumos que sÃo sabidamente nocivos. Para mitigar estes malefÃcios, pode-se utilizar as Misturas AsfÃlticas Mornas (MAMs).Essas misturas requerem temperaturas mais baixas do que as temperaturas normalmente empregadas na produÃÃo de Concretos AsfÃlticos (CAs).à possÃvel, ainda,combinar as duas tÃcnicas (MARQs e MAMs) utilizando as Misturas AsfÃlticas Recicladas Mornas (MARM).O presente trabalho tem como objetivo principal avaliar MARMs no que diz respeito a trabalhabilidade, a compactabilidade e ao comportamento mecÃnico das mesmas. Para isso, foram dosadas e caracterizadas em laboratÃrio 14 misturas do tipo CA, quais sejam: (i) duas misturas de referÃncia (uma dosada atravÃs da metodologia de dosagem Marshall e outra atravÃs da metodologia Superpave), (ii) trÃs MAMs (dosadas atravÃs da metodologia de dosagem Marshall) com, respectivamente, 20, 30 e 40ÂC de diminuiÃÃo das temperaturas utilizadas em todas as etapas do processo de dosagem, (iii) trÃs MAMs (dosadas atravÃs da metodologia de dosagem Superpave) com as mesmas diminuiÃÃes nas temperaturas jà mencionadas, (iv) trÃs MARQs (dosadas atravÃs da metodologia de dosagem Superpave) com 15, 35 e 50% de fresado em suas composiÃÃes e (v) trÃs MARMs com os mesmos percentuais de fresado utilizados nas MARQs e com a diminiÃÃo de temperatura de 40ÂC em todas as fases do processo. AlÃm das 14 misturas aqui descritas que foram avaliadas na fase de laboratÃrio do presente trabalho, foram dosadas outras quatro misturas em laboratÃrio para serem testadas em campo com a construÃÃo de trechos experimentais.Analisando-se os resultados encontrados percebe-se que as MARMs tem um potencial promissor, tendo em vista que as mesmas apresentaram parÃmetros volumÃtricos encontrados durante o processo de dosagem e comportamento mecÃnico similares se comparados aqueles obtidos para as misturas asfÃlticas convencionais. Tais parÃmetros foram alcanÃados sem a necessidade de mudanÃas nos equipamentos utilizados para a produÃÃo dessas misturas. Foi possÃvel atingir patamares de economia no consumo de CAP virgem de atà 45% e de agregados convencionais virgens de atà 50%, alÃm de uma possÃvel diminuiÃÃo do consumo energÃtico durante o processo de produÃÃo dessas misturas asfÃlticas devido a reduÃÃo das temperaturas em atà 40ÂC. / The paving process uses large amounts of natural resources thus requiring actions to mitigate the resulting environmental damage. Observing a road section, you can highlight activities that affect the environment, such as deforestation, mineral extraction for the production of aggregates and petroleum extraction and refining for use in asphalt layers. This activity also uses processes that generate large volumes of environmental liabilities, such as milling and demolition material. The reclaimed asphalt pavement (RAP) can be recycled and reused, for example in the production of RAP hot mixtures asphalts (HMA). The high temperatures that need to be used to produce acceptable workability of the asphalt mixtures can affect the environment and the workers on the construction site. The asphalt binder when subjected to high temperatures releases fumes known to be health hazardous. To mitigate these hazards, one can use the warm mixtures asphalt (WMA). This technology uses lower temperatures than the ones normally applied for HMA, thereby aforementioned emissions can be mitigated. It is also possible that the asphalt mixtures can be implemented with lower energy consumption. One can still use RAP WMA making use of both solutions already mentioned, RAP HMA and WMA. This work aims to use both techniques together and evaluate RAP WMA with respect to its workability, compactability and mechanical behavior. In order to achieve this objective it will be characterized in the laboratory HMAs with different RAP percentages and WMA additive. Such mixtures are also subsequently tested in the field using experimental sections. Analyzing the results it is noticed that the RAP WMAs has a promising potential since they presented the same volumetric parameters and mechanical behavior when compared to those obtained for the conventional asphalt mixtures. These parameters have been achieved without the need for changes in the equipment used for the production of these mixtures. It was possible to attain savings in binder consumption of up to 45% and conventional aggregates of up to 50%.A reduction in energy consumption is also achieved during the production of asphalt mixtures due to reductions in temperature to 40ÂC.
70

The effects of Foam Rolling and Static Stretching on bilateral forward jumping ability and flexibility of the hamstrings musculature

Wärnström, Mathias January 2016 (has links)
Background: Foam rolling (FR) is a promising new trend in the world of resistance training, sports and  athletics. It is often used as a warm up activity as a substitute or addition to  stretching modalities such as static stretching (SS). The proposed benefits behind FR is that it can lead to  both acute and chronic increases in performance and flexibility. Aim: The aim of this study was to investigate the effects of two different warm­up intervention protocols  of the hamstrings musculature on: 1) Performance in the bilateral standing long jump 2) Flexibility in a  supine active­knee­extension test. Method: The study consisted of sixteen male participants who were all healthy adult recreational athletes.  The two different interventions were, a) Static Stretching protocol (SS) and b) a Foam Rolling protocol  (FR). These were compared to a baseline warm up (BLWU). The SS consisted of 1 x 30 seconds of active  SS using the lying supine active­knee­extension position after a short warm­up. The FR consisted of 1  bout of 30 seconds of FR of the hamstrings musculature of each leg after a short warm­up. BLWU  consisted of a short warm­up (5 submaximal bilateral standing long jumps). Performance was measured  using a bilateral standing long jump test. Flexibility was measured with a goniometer using a lying supine active ­knee­ extension test. The student’s t­test was used to study differences between and within groups (BLWU, SS, FR). Results: No differences between BLWU and Post­SS (p=0.89) as well as BLWU compared to Post­FR (p=0.86) was detected for performance. However, an increase in flexibility was shown favoring Post­SS over BLWU (p=0.021) as well as Post­FR over BLWU (p=0.045). No significant difference was seen  between changes in the Post­SS and Post­FR groups in either performance or flexibility (p=0.887 and  p=0.944 respectively). Conclusion: It seems that both SS and FR are similarly viable and effective methods for acute increases  in flexibility in the active­knee­extension test without subsequent decreases in performance of the bilateral standing long jump.

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