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Correlation of Polar Mesospheric Cloud Observational Data for the Northern Hemisphere in 2007
No full textPolar mesospheric clouds (PMCs) occur in the cold (\u3c150 K) summer mesosphere at latitudes greater than 40°. Because of their high altitude (~82 to 84 km), the sun still illuminates them from ~5° to 16° below the horizon. This phenomenon gives them the name of noctilucent clouds when viewed from the ground during twilight
Investigating Thermospheric Gravity Wave Amplitudes in the High Arctic
No full textAtmospheric gravity waves (AGWs) transfer energy and momentum. They propagate upwards away from their dominant weather sources and can penetrate deeply into the mesospheric and thermospheric region (~87 - 400km)
DEEPWAVE Initial Investigation of Mesospheric Gravity Wave Signatures Generated by Variable Orographic Forcing Over Lauder Station, New Zealand (45°S)
No full textThe DEEPWAVE program is an international collaboration designed to identify, characterize, and predict the generation and propagation of deeply propagating (up to ~100km altitude) atmospheric gravity waves. The Atmospheric Imaging Lab at Utah State University (USU) operated two Advanced Mesospheric Temperature Mappers (AMTMs), on the GV aircraft and at Lauder NZ (45°S 169°E), from May 31 to July 22 of 2014. The AMTM is uniquely capable of measuring horizontal temperature wave structures in the OH airglow at 87km altitude
USU Rayleigh Lidar and Assimilative Models to Examine Coupling Between the Mesosphere and Lower Atmosphere
No full textThe scarcity of supporting mesospheric measurements leaves assimilative models lacking when it comes to connecting lower and upper atmospheric phenomena. Observational records from the Rayleigh-scatter lidar system at the Atmospheric Lidar Observatory (ALO-USU; 41.74° N, 111.81° W), a part of Utah State University\u27s Center for Atmospheric and Space Sciences (CASS), include absolute temperatures in this regime that can be compared with the upper bounds of reanalysis models near the stratopause. This study examines surface weather surrounding the appearance of significant temperature outliers in ALO-USU observations and model data alike. Speculation on possible relationships between conditions in the troposphere and mesosphere follows. Model data sources comprise the Climate Prediction Center (CPC), the European Centre for Medium-Range Weather Forecasts\u27 (ECMWF) ERA-Interim, and NASA\u27s Modern-Era Retrospective Analysis for Research and Applications (MERRA)
A Comprehensive Examination of Age-Related Lower Limb Muscle Function Asymmetries Across a Variety of Muscle Action Types
Get PDFPrevious research has found that lower limb muscle asymmetries increase with age and are linked to fall and injury risks. However, past studies lack a wide variety of muscle function modes and measures as well as comparison to a comparable younger age group. The purpose of this study was to examine age-related lower limb muscle function asymmetries across a variety of muscle action types and velocities in young and old adults. Lower limb balance, strength, power, and velocity were evaluated with concentric, isometric, isotonic, and eccentric muscle actions during a single-leg stance test and on single- and multi-joint dynamometers in 29 young (age = 21.45 ± 3.02) and 23 old (age = 77.00 ± 4.60) recreationally active men and women. Most (15 of 17) variables showed no statistical (p \u3e 0.05) or functional (10% threshold) limb asymmetry for either age group. There was a significant main effect (p = 0.046; collapsed across groups) found for asymmetry (dominant \u3e non-dominant) for the isotonic peak velocity variable. There was a significant (p = 0.010) group × limb interaction for single-joint concentric peak power produced at a slow (60 deg/s) velocity due to the non-dominant limb of the young group being 12.2% greater than the dominant limb (p \u3c 0.001), whereas the old group was not asymmetrical (p = 0.965). The findings of this investigation indicate there is largely no age-related asymmetry of the lower limbs across a range of muscle function-related variables and modes, with a couple of notable exceptions. Also, the significant asymmetries for the isotonic peak velocity variable perhaps show the sensitivity of this uncommonly used measure in detecting minimally present muscle function imbalances
Workflow and Best Practices of Planting Design in Virtual Reality
Get PDFThe purpose of this study is to develop a technical workflow and deliver an instructional module for teaching planting design in Virtual Reality (VR). The developed workflow and instructional model will be presented to students enrolled at Utah State University in the Landscape Architecture and Environmental Planning (LAEP) Department. The first objective of this thesis project is to explore and create a successful workflow of basic planting design principles and apply them in virtual reality with the use of new technology. The virtual reality and planting design software that were explored were Twinmotion, VR Sketch, SketchUp, AutoCAD, Land FX, Gravity Sketch, and Unreal Engine 5. After exploration and testing, Unreal Engine 5 and Gravity Sketch were not used, due to the programs either being too complicated to learn in a short amount of time, or because the program was to be used for a portion of the design process not included in this workflow. The creation of a workflow will introduce the application of virtual reality technology into the landscape architecture industry by preparing students with the requisite knowledge to successfully design in virtual reality prior to their entry into the workforce. The second objective is to introduce students to the application of virtual reality in relation to planting design. Students will be introduced to the basics of virtual reality through a walkthrough video and an in-class lecture on the developed workflow, followed by a vignette and a final design assignment. The vignette and the final design will allow students to apply what they have learned via the workflow. These objectives will be achieved using the LAEP 3500 Planting Design course taught during the fall semester to MLA graduate students and matriculated juniors in the LAEP department. Expected results of this thesis include landscape architecture students developing skills to create unique planting designs, within the constraint of given assignments, while using virtual reality technology, which by allows students to view their design ‘in person.
Acute Effects of Multi-Joint Eccentric Exercise on Lower Extremity Muscle Activation Measured During Land and Water Walking
Get PDFAlthough prior literature has established the preliminary clinical benefits of aquatic exercise across various clinical populations, there is a need to explore the potential for including aquatic-based movement as a key component of a multi-modal approach toward improving mobility and reducing fall risk. Eccentric exercise may complement aquatic exercise given that movements performed in water immersion tend to be low impact. Eccentric exercise may also improve the passive stiffness of lower extremity extensors, which gives an additional rationale for the potential of eccentric exercise to reduce fall risk when combined with aquatic exercise. There may also be an acute response to spinal reflex activity post-eccentric exercise, which could enhance the benefit of performing aquatic exercise if eccentric exercise is performed immediately prior. The purpose of this study was to compare lower-limb muscle activation during gait performed in water versus on land, before and after a short bout of eccentric exercise, in order to investigate the potential of a multi-modal approach toward improving gait abnormalities that relate to fall risk in older adults. Twenty-six healthy, recreationally active young adults completed the study. Each participant walked on land and in water, both prior to and after eccentric exercise for 2-min each while root-mean-square (RMS) muscle activity of the tibialis anterior (TA), medial gastrocnemius (GM), biceps femoris (BF), and vastus lateralis (VL) were recorded during the swing and stance phases of gait, using surface electromyography. A two-way within-subjects analysis of variance was used to evaluate for main effects and interactions. Main effects of environment were observed across all measures of muscle activation (F = 4.5 – 602.6, p \u3c0.001 – 0.036) except for BF RMS during the swing phase (F = 0.2, p = 0.699). Co-activation of the thigh during swing was the only measure to reveal an environment × eccentric exercise interaction (F = 5.4, p \u3c 0.001) and main effect of eccentric exercise (F = 7.4, 2 p = 0.008).The significant interaction on Co-activation of the thigh during swing appeared to be influenced by a non-significant reduction in VL RMS observed for post-eccentric exercise land walking. This suggests that participants may have adopted a different motor strategy, possibly anticipating the greater vertical ground reaction forces during foot impact in land walking compared to water walking, leading to reduced VL activation during swing. The results of this study provide evidence that additional research is warranted and may be aimed at exploring the potential of a multi-modal training approach involving aquatic treadmill walking and eccentric exercise to enhance mobility and address fall risk in clinical populations
Creating Sustainable School and Home Gardens: Native Bee Homes
Get PDFThis fact sheet is part of a series about creating sustainable school and home gardens. It provides information and resources on bee homes, including learning about bees and how to help them, how to obtain and install bee homes, fall cocoon care, fun facts, and resources
Method Development for the Extraction and Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Wastewater and Biosolids
Get PDFPer and poly-fluorinated alkyl substances (PFAS) are manufactured chemicals that have water and grease repellant properties and do not readily biodegrade. PFAS are present in many consumer products and end up in waste systems and the environment. Studies have shown that PFAS can have adverse health effects on humans and animals.
There are many challenges to processing and analyzing samples containing PFAS including: adsorption of PFAS to equipment, contamination from equipment containing PFAS, and the high sensitivity needed to analyze for PFAS in the parts per trillion detection range. The United States Environmental Protection Agency (EPA) has been developing methods to analyze for PFAS in environmental samples, starting with drinking water and moving towards more complex environmental matrixes. Testing of these methods with available laboratory equipment must occur to optimize a lab\u27s capacity to quantify PFAS.
To quantify them, PFAS must first be extracted from a sample and then analyzed using liquid chromatography paired with mass spectrometry. This study compares extraction and analytical methods for the quantification of PFAS in biosolids and wastewater. Analytical methods based on EPA Methods 533 and 1633 were compared and the results from Method 533 were more precise and accurate than Method 1633. An automated and manual extraction method were compared for the extraction of PFAS from biosolids and the manual method was determined to produce better recovery of PFAS. Finally, two methods of sample clean up and concentration for wastewater and biosolids samples were compared between methods developed at the Utah Water Research Lab and EPA Method 1633. Method 1633 was found to have higher percent recoveries of PFAS for biosolids and wastewater.
From these results it is recommended that for extraction of biosolids EPA Method 1633 be used. For SPE cleanup it is recommended that EPA Method 1633 be followed for both wastewater and biosolids. For analysis EPA Method 533 is recommended for both wastewater and biosolids samples. These methods have shown the best recoveries of extraction standards and the most consistency in results
Movement Behavior and Habitat Selection of Juvenile Mountain Lions (\u3ci\u3ePuma concolor\u3c/i\u3e) During Three Behavioral States of Dispersal
Get PDFJuvenile dispersal, the act of moving from their natal range to the place where they eventually reproduce and establish an adult home range is hazardous. Juveniles must travel and find food across unfamiliar landscapes, where they must also cross roads, avoid harvest, and navigate developed landscapes. Despite the inherent dangers of dispersal, this demographic process is important for finding suitable mates and reducing inbreeding depression. Wildlife conservation concerns arise when individuals are unable to disperse due to a loss of connectivity, as this can negatively impact population demographics and genetic diversity. We explored the effects of hunting and human-developed landscapes on the dispersal behavior of juvenile mountain lions (Puma concolor) in two geographically separated populations subject to different management practices—one with hunting in Nevada and one protected from hunting in California. We used GPS-collar data from 12 and 13 individuals in Nevada and California, respectively, and divided juvenile dispersal into three distinct movement states: exploratory, departure, and transient home range. We then compared used and available locations to identify habitat selection and avoidance characteristics. Our study revealed consistencies between the two sites, including selection for habitat features such as forest, shrub, elevation, and terrain ruggedness. Notably, only the population subjected to hunting pressure exhibited avoidance of human-developed habitat types. Results suggest that hunting influences the dispersal behavior of juvenile mountain lions. This thesis highlights the utility of research using comparative populations to further our understanding of dispersal behavior