205 research outputs found

    The Peasant Dance

    Get PDF

    Long-line culture of red seaweed in the Pacific Northwest

    Get PDF
    The goal of this study was to adapt open-water rope culture techniques to the native red seaweed Devaleraea mollis to support a new seaweed aquaculture industry in Humboldt Bay, California. The specific objectives for this study were to: 1) evaluate the growth of D. mollis cultivated at different depths and seasons (fall/winter, spring/summer), 2) estimate nutrients removed by D. mollis from the water, and 3) measure heavy metals and pesticides to determine potential health risk upon ingestion. Bundles of seaweed were inserted into 3 m long weighted vertical lines attached to two horizontal long-lines suspended by floats. Two four-month trials (September to December 2020 and April to July 2021) were compared. Long-lines in Trial 1 were seeded on the same date, and data was pooled from both long-lines. Data was analyzed separately for each long line in Trial 2 as the lines were seeded on different dates. Both depth (p\u3c0.001) and month (p\u3c0.002, two-way ANOVA, Tukey HSD test) had significant effects on wet weight for the first trial with depths 0 m and 1 m and months November and December producing the best growth. For Trial 2 only depth was significant (p=0.006) for long-line 1 with the 0 m depth producing the best growth while both depth (p\u3c0.001) and month (p=0.006) significantly affected wet weight for long-line 2 with 0 m and the month of May producing the best growth. Maximum growth rate from Trial 1 was 0.21 g/day, and 0.19 g/day from Trial 2. A total of 1.20 kg of carbon, 0.12 kg of nitrogen, and 0.02 kg of phosphorus were removed from the water by the seaweed produced in this study. All pesticides were found to be undetectable, and all heavy metals were either undetectable or below action levels with the exception of manganese for 3 m in Trial 1 and 2 m and 3 m in Trial 2 (21.0 mg/kg, 77.6 mg/kg, 93.3 mg/kg respectively). Results from this study suggest optimal growth occurs in the winter and early spring at no more than 1 m in depth, D. mollis’s potential for nutrient bioextraction, and that D. mollis grown in Humboldt Bay poses low risk to consumers for heavy metals and pesticides

    CALIBRATED SHORT TR RECOVERY MRI FOR RAPID MEASUREMENT OF BRAIN-BLOOD PARTITION COEFFICIENT AND CORRECTION OF QUANTITATIVE CEREBRAL BLOOD FLOW

    Get PDF
    The high prevalence and mortality of cerebrovascular disease has led to the development of several methods to measure cerebral blood flow (CBF) in vivo. One of these, arterial spin labeling (ASL), is a quantitative magnetic resonance imaging (MRI) technique with the advantage that it is completely non-invasive. The quantification of CBF using ASL requires correction for a tissue specific parameter called the brain-blood partition coefficient (BBPC). Despite regional and inter-subject variability in BBPC, the current recommended implementation of ASL uses a constant assumed value of 0.9 mL/g for all regions of the brain, all subjects, and even all species. The purpose of this dissertation is 1) to apply ASL to a novel population to answer an important clinical question in the setting of Down syndrome, 2) to demonstrate proof of concept of a rapid technique to measure BBPC in mice to improve CBF quantification, and 3) to translate the correction method by applying it to a population of healthy canines using equipment and parameters suitable for use with humans. Chapter 2 reports the results of an ASL study of adults with Down syndrome (DS). This population is unique for their extremely high prevalence of Alzheimer’s disease (AD) and very low prevalence of systemic cardiovascular risk factors like atherosclerosis and hypertension. This prompted the hypothesis that AD pathology would lead to the development of perfusion deficits in people with DS despite their healthy cardiovascular profile. The results demonstrate that perfusion is not compromised in DS participants until the middle of the 6th decade of life after which measured global CBF was reduced by 31% (p=0.029). There was also significantly higher prevalence of residual arterial signal in older participants with DS (60%) than younger DS participants (7%, p = 0.005) or non-DS controls (0%, p \u3c 0.001). This delayed pattern of perfusion deficits in people with DS differs from observations in studies of sporadic AD suggesting that adults with DS benefit from an improved cardiovascular risk profile early in life. Chapter 3 introduces calibrated short TR recovery (CaSTRR) imaging as a rapid method to measure BBPC and its development in mice. This was prompted by the inability to account for potential changes in BBPC due to age, brain atrophy, or the accumulation of hydrophobic A-β plaques in the ASL study of people with DS in Chapter 2. The CaSTRR method reduces acquisition time of BBPC maps by 87% and measures a significantly higher BBPC in cortical gray matter (0.99±0.04 mL/g,) than white matter in the corpus callosum (0.93±0.05 mL/g, p=0.03). Furthermore, when CBF maps are corrected for BBPC, the contrast between gray and white matter regions of interest is improved by 14%. This demonstrates proof of concept for the CaSTRR technique. Chapter 4 describes the application of CaSTRR on healthy canines (age 5-8 years) using a 3T human MRI scanner. This represents a translation of the technique to a setting suitable for use with a human subject. Both CaSTRR and pCASL acquisitions were performed and further optimization brought the acquisition time of CaSTRR down to 4 minutes which is comparable to pCASL. Results again show higher BBPC in gray matter (0.83 ± 0.05 mL/g) than white matter (0.78 ± 0.04 mL/g, p = 0.007) with both values unaffected by age over the range studied. Also, gray matter CBF is negatively correlated with age (p = 0.003) and BBPC correction improved the contrast to noise ratio by 3.6% (95% confidence interval = 0.6 – 6.5%). In summary, the quantification of ASL can be improved using BBPC maps derived from the novel, rapid CaSTRR technique

    RB30-252 Sex and Age as Factors in Cattle Feeding

    Get PDF
    Varying economic conditions and changes in the demands of the meat consuming public have been responsible for the turns that have taken place in the beef industry during recent years. Both feeder and producer must recognize and conform to these changes if they are to continue in business. Among the most important of these changes have been the turn toward the marketing of lighter cattle and the gradual disappearance from feed lots of two- and three-year-old animals. Furthermore, the cattle population of the United States is fast reaching stabilization with the resulting effect that more heifers are being marketed, since only one-fourth of the heifer crop is needed to replace worn-out breeding animals. Realizing the increasing importance of the heifer problem from the standpoint of the producer, feeder, and consumer, the Nebraska Experiment Station undertook to compare steers and heifers in a series of trials both in the feedlot and in the beef. It was hoped that these experiments would yield results which would bring out existing differences, if any, between steers and heifers both in quality and quantity of beef produced and thus provide or disprove many of the complaints against heifers. The results of these trials are summarized in this bulletin. Age as well as the sex factor has been considered, since two-year-olds, yearlings, and calves were included in these trials

    Religious Activity and Time Use of 149 Utah Husbands

    Get PDF
    The purpose of this study was to analyze 149 Utah L.D.S. husband/ father\u27s time spent in various activities by their level of religious activity, and to re late their organization participation time to their household work time. Data for this study came f rom the Utah port ion of the Interstate Comparison of Urban /Rural Families\u27 Time Use This study used a sub-sample of the original Utah sample. Data used were collected through church affiliation and activity questionnaires and time diaries. Level of religious activity in the L.D.S. Church was considered along with husbands\u27 time allocated to organization participation, social and recreational activities, and household work. Household work tasks included food preparation, dishwashing, housecleaning, maintenance of home, yard, car and pets, physical care of household members, and non-physical care of household members. Statistical tests used were analysis of variance, correlation and multiple regression analysis. Findings revealed that level of religious activity did not significantly affect the time respondents allocated to either household work or to social and recreational activities. It did significantly affect their organization participation time. The more active respondents were in the L.D.S. Church, the more time they allocated to organization participation. Organization participation time significantly affected the time respondents allocated to maintenance of home, yard, car and pets, and to all household work. As organization participation time decreased, time in these two areas significantly increased. Variations in husbands\u27 household work time were not significantly explained by any of the following variables: age of younger child, level of religious activity, hours of wife\u27s paid employment, hours of husband\u27s paid employment, husband\u27s social and recreational time, husband\u27s organization participation time, annual household income, rural or urban residence, or whether husband\u27s house hold task performance time was measured on a weekend day or a weekday

    Study and Demonstration of Planning and Scheduling Concepts for the Earth Observing System Data and Information System

    Get PDF
    The University of Colorado's Laboratory for Atmospheric and Space Physics (CU/LASP) along with the Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL) designed, implemented, tested, and demonstrated a prototype of the distributed, hierarchical planning and scheduling system comtemplated for the Earth Observing System (EOS) project. The planning and scheduling prototype made use of existing systems: CU/LASP's Operations and Science Instrument Support Planning and Scheduling (OASIS-PS) software package; GSFC's Request Oriented Scheduling Engine (ROSE); and JPL's Plan Integrated Timeliner 2 (Plan-It-2). Using these tools, four scheduling nodes were implemented and tied together using a new communications protocol for scheduling applications called the Scheduling Applications Interface Language (SAIL). An extensive and realistic scenario of EOS satellite operations was then developed and the prototype scheduling system was tested and demonstrated using the scenario. Two demonstrations of the system were given to NASA personnel and EOS core system (ECS) contractor personnel. A comprehensive volume of lessons learned was generated and a meeting was held with NASA and ECS representatives to review these lessons learned. A paper and presentation on the project's final results was given at the American Institute of Aeronautics and Astronautics Computing in Aerospace 9 conference

    Feeding and Care of Calves

    Get PDF
    It is not infrequent that considerable difficulty is encountered in raising calves with limited amounts of milk or none at all. Requests for information on calf gruels, mixed grain feeds, and commercial supplements are frequent enough to make a short circular upon this subject seem desirable. Furthermore, as the more diversified agricultural program gets under way these requests are increasmg

    Novel Calibrated Short TR Recovery (CaSTRR) Method for Brain-Blood Partition Coefficient Correction Enhances Gray-White Matter Contrast in Blood Flow Measurements in Mice

    Get PDF
    The goal of the study was to develop a novel, rapid Calibrated Short TR Recovery (CaSTRR) method to measure the brain-blood partition coefficient (BBPC) in mice. The BBPC is necessary for quantifying cerebral blood flow (CBF) using tracer-based techniques like arterial spin labeling (ASL), but previous techniques required prohibitively long acquisition times so a constant BBPC equal to 0.9 mL/g is typically used regardless of studied species, condition, or disease. An accelerated method of BBPC correction could improve regional specificity in CBF maps particularly in white matter. Male C57Bl/6N mice (n = 8) were scanned at 7T using CaSTRR to measure BBPC determine regional variability. This technique employs phase-spoiled gradient echo acquisitions with varying repetition times (TRs) to estimate proton density in the brain and a blood sample. Proton density weighted images are then calibrated to a series of phantoms with known concentrations of deuterium to determine BBPC. Pseudo-continuous ASL was also acquired to quantify CBF with and without empirical BBPC correction. Using the CaSTRR technique we demonstrate that, in mice, white matter has a significantly lower BBPC (BBPCwhite = 0.93 ± 0.05 mL/g) than cortical gray matter (BBPCgray = 0.99 ± 0.04 mL/g, p = 0.03), and that when voxel-wise BBPC correction is performed on CBF maps the observed difference in perfusion between gray and white matter is improved by as much as 14%. Our results suggest that BBPC correction is feasible and could be particularly important in future studies of perfusion in white matter pathologies

    Nature grasping by a cable-driven under-actuated anthropomorphic robotic hand

    Get PDF
    Human hand is the best sample for humanoid robotic hand and a nature grasping is the final target that most robotic hands are pursuing. Many prior researches had been done in virtual and real for simulation the human grasping. Unfortunately, there is no perfect solution to duplicate the nature grasping of human. The main difficulty comes from three points. 1. How to 3D modelling and fabricate the real hand. 2. How actuated the robotic hand as real hand. 3. How to grasp objects in different shapes like human hand. To deal with these three problems and further to provide a partial solution for duplicate human grasping, this paper introduces our method to solve these problems from robotic hand design, fabrication, actuation and grasping plan. Our modelling progress takes only around 12 minutes that include 10 minutes of 3D scanning of a real human hand and two minutes for changing the scanned model to an articulated model by running our algorithm. Our grasping plan is based on the sampled trajectory and easy to implement for grasping different objects. Followed these steps, a seven DOF robotic hand is created and tested in the experiments
    • …
    corecore