387 research outputs found
Keeping Up with Sea-Level Rise: Salt Marsh Accretion. Subjects: Earth Science, Marine / Ocean Science Grades: 9-12
This lesson uses a hands-on demonstration to give students an understanding of how this critical ecosystem can keep pace with sea-level rise. Students will have the opportunity to make and test hypotheses about how different animals can affect salt marsh resilience, after learning about simple ecological interactions
Greek myth and America:the hero and family dynamics in 'Percy Jackson and the Olympians' by Rick Riordan
Physical Activity, Body Mass Index, and Clustered Metabolic Risk in U.S. Adolescents: 2007-2012 NHANES.
Objectives: To examine variation in clustered metabolic risk (cMetS) in adolescents classified as not overweight/active (NOA), not overweight/not active (NONA), overweight/active (OA), and overweight/not active (ONA).
Background: While studies to date have shown that children and adolescents who meet the current physical activity (PA) recommendations and maintain a healthy body weight demonstrate significantly lower cardiometabolic risk, there are some studies that suggest the relationship between PA and metabolic risk may be mediated by adiposity.
Methods: The sample included adolescent participants (n=875; 12-17 years) of the 2007-2012 National Health and Nutrition Examination Survey (NHANES). The cMetS score included triglycerides, high-density lipoprotein cholesterol, fasting plasma glucose, and mean arterial pressure. Age- and sex-specific body mass index (BMI) percentiles were utilized; overweight was defined as BMI percentile ≥ 85th. Activity data included self-reported frequency of moderate-to-vigorous PA. Adolescents reporting ≥ 60 min/day of PA were considered “active”. General linear models, adjusted for age, sex, and race-ethnicity, were used. A six-year fasting sample weight was applied to the analyses in order to ensure representativeness of the data.
Results: The cMetS scores were significantly (p
Conclusions: The cMetS scores were higher in OA and ONA adolescents when compared to those classified as NOA. Whereas only ONA males demonstrated significantly higher cMetS score when compared to the NOA referent, both OA and ONA cMetS scores (vs NOA) were significantly higher in females
Digital Pathology in the Clinic: Training, Validation and Patient Safety
Digital pathology is a technology with the potential to transform the way in which histopathological diagnoses are made and cancer diagnostic services are delivered. Despite this, clinical deployment of digital slides has lagged behind research and educational uses. This thesis describes some of the key barriers to widespread clinical adoption, which largely relate to a lack of guidance and information for pathologists regarding validation, training and patient safety. The evidence base for patient safety was analysed in a novel way to provide the basis for a validation and training protocol which was trialled in real world clinical settings, and guidance documents were developed and disseminated to the clinical pathology community to help with the transition from glass slide to digital slide reporting.
In Chapter 1, background information and an overview of the published literature regarding clinical use of digital pathology is provided. In the second chapter, the results of a national survey on access to and usage of digital pathology hardware, in addition to attitudes to digital pathology, is presented.
One significant barrier preventing digital pathology adoption has been a lack of widespread acceptance of digital slides as a safe alternative to conventional glass slides. Historically, validation literature investigating the safety of digital pathology as an alternative to conventional light microscopy has focussed on concordance metrics of glass and digital diagnoses, when arguably, it is appreciation of discordant cases that provides the clinical pathologist with the best opportunity to evaluate the scope of safe digital practice in their specialty. Chapter 3 describes a novel study to analyse diagnostic accuracy of whole slide imaging and identify key training and educational targets for novice digital pathologists. Chapter 4 presents the validation and training protocol developed by the author for Leeds Teaching Hospitals NHS Trust, which was subsequently adopted by the Royal College of Pathologists as an example of best practise in digital pathology implementation.1 Chapter 5 describes the deployment of this protocol to train and validate the primary digital diagnosis of cohorts of breast and neuro- pathologists. Chapter 6 introduces modifications of the protocol for use for more niche reporting scenarios: frozen section diagnosis and immunohistochemistry assessment. Chapter 7 responds to concerns in the pathology community regarding accreditation of digital services, and the use of WSI for primary assessment of screening programme specimens.
The body of work presented in this thesis has generated multiple peer reviewed publications which have influenced national and international digital pathology guidance. In this time period, enormous progress has been made in converting digital pathology from a niche technology for the early adopter to a mainstream topic at clinical digital pathology conferences, and the number of deployments and planned deployments in the National Health Service and beyond has risen dramatically. The use of digital slides in routine clinical practice represents a major departure from conventional light microscopy working practices, and the author hopes this work will help the pathology community maintain diagnostic quality in a time of change
The Role of Ecological Interactions in Saltmarsh Geomorphic Processes
Accelerated sea-level rise poses a significant threat to coastal habitats. Salt marshes are critical coastal ecosystems, providing a host of services such as storm protection, food production, and carbon storage. Persistence of salt marshes in the face of rising sea levels relies, in part, on vertical accretion. Current ecogeomorphic models and empirical studies emphasize the importance of the positive relationship between plant production and vertical accretion via sediment trapping by stems aboveground and belowground organic matter production. Thus, changes in plant production influence salt marsh persistence with sea-level rise. However, studies and models of marsh accretion do not consider the effects of animal-mediated changes in plant production. Here, I tested how two co-occurring marsh crustaceans, Uca pugnax (marsh fiddler crab) and Sesarma reticulatum (purple marsh crab), which have contrasting effects on smooth cordgrass (Spartina alterniflora) production, indirectly influence sediment deposition and belowground organic matter contribution, through observational surveys and field manipulation. S. reticulatum feeds directly on S. alterniflora, while U. pugnax facilitates S. alterniflora production through burrowing and biodeposits. I found that U. pugnax facilitated S. alterniflora biomass in some marshes, but not others. However, this facilitation of S. alterniflora biomass did not enhance sediment deposition. U. pugnax had no effect on belowground components of vertical accretion (i.e. root production and decomposition). These results suggest that in isolation, U. pugnax has little impact on saltmarsh geomorphic processes. S. reticulatum reduced S. alterniflora above- and belowground biomass; however, sediment deposition increased as S. alterniflora biomass decreased, contrary to models of ecogeomorphology. This trend was likely due to sediment being resuspended by crab bioturbation, as U. pugnax abundances were higher in S. reticulatum-grazed areas than in non-grazed areas. When U. pugnax occurred in areas of low S. reticulatum grazing, S. alterniflora biomass and sedimentation was similar to areas with only U. pugnax. I suggest that the negative impacts of S. reticulatum are exaggerated when intense grazing results in completely unvegetated areas and subsequent increases in U. pugnax density, where bioturbation erodes sediments. Thus, while S. reticulatum can increase the susceptibility of marsh sediments to physical erosion by removing vegetation, it may also do so by facilitating U. pugnax bioturbation. However, when S. reticulatum grazing intensity is low, facilitation of S. alterniflora growth by U. pugnax can mitigate the negative effect of grazing, which suggests that the net effect of these species may depend on their relative abundance. This study demonstrates that ecological interactions, in addition to physical processes, have significant effects on marsh persistence as sea level rises, and merit incorporation into ecogeomorphic models and empirical studies of marsh accretion
A multi-scale investigation of ecologically relevant effects of agricultural runoff on amphibians
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 25, 2010).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Raymond D. Semlitsch.Vita.Ph. D. University of Missouri--Columbia 2008.Modification of landscapes for agricultural production can introduce agrochemicals into surface waters and degrade aquatic habitats used by many amphibians for breeding and larval development. Although many ecotoxicological studies have shown that contaminants common in agricultural runoff have the potential to cause mortality, immunosuppression, or reproductive abnormalities in amphibians, we have a very poor understanding of how exposure to agricultural runoff may affect amphibian population persistence when exposures occur in realistic contexts. Using laboratory studies, field studies, and landscape level surveys, I established that herbicides common in runoff can cause mortality and alter life history traits in amphibian larvae under laboratory conditions at levels as low as EPA drinking water standards, although laboratory exposures to water from agricultural streams generally enhanced larval performance. In field enclosure studies, tadpole performance in agricultural streams showed more year-to-year variability than in reference condition streams. Landscape level surveys confirmed that the majority of anurans present in the study area use streams for both calling activity and reproduction. Physical stream habitat characteristics were better predictors of capture rates than local or watershed land use, indicating that habitat availability may be an important constraint on amphibian success at stream sites.Includes bibliographical reference
Learning to be Effective Allies to Indigenous Communities: Perspectives from the Sheridan College Community - Research Report
In Our Voices: Sheridan’s Indigenous Community and Allies is an arts-based research project conducted in collaboration with the Centre for Indigenous Learning and Support at Sheridan College. The larger research project from which these findings emerged was focused on the dual purposes of understanding how the Sheridan community views the role of an effective ally to Indigenous communities and to highlight stories of strength, resilience and discovery of Sheridan’s Indigenous community members. The research was funded by a Sheridan College SRCA growth grant. This study received ethics approval from the Sheridan Research Ethics Board in May 2018. Data collection began in September 2018 and was completed in March 2019. This report focuses on the findings that emerge from interviews with faculty, staff and administrators and Sheridan’s Indigenous community members as well as from an online survey that sought to understand what it means to be an ally to Indigenous communities.
The three videos below emerged from Phase 1 of the research project and feature the voices of Sheridan’s Administrators, Faculty and Staff.
Video 1: What does it mean to be an effective ally to Indigenous Communities?
Video 2: What can Sheridan do to be more effective allies to Indigenous Communities?
Video 3: How can Sheridan students be allies to Indigenous Communities while they are at Sheridan and as they enter the field
Sea Level Rise may Increase Extinction Risk of a Saltmarsh Ontogenetic Habitat Specialist
Specialist species are more vulnerable to environmental change than generalist species. For species with ontogenetic niche shifts, specialization may occur at a particular life stage making those stages more susceptible to environmental change. In the salt marshes in the northeast U.S., accelerated sea level rise is shifting vegetation patterns from flood-intolerant species such as Spartina patens to the flood-tolerant Spartina alterniflora. We tested the potential impact of this change on the coffee bean snail, Melampus bidentatus, a numerically dominant benthic invertebrate with an ontogenetic niche shift. From a survey of eight marshes throughout the northeast U.S., small snails were found primarily in S. patens habitats, and large snails were found primarily in stunted S. alterniflora habitats. When transplanted into stunted S. alterniflora, small snails suffered significantly higher mortality relative to those in S. patens habitats; adult snail survivorship was similar between habitats. Because other habitats were not interchangeable with S. patens for young snails, these results suggest that Melampus is an ontogenetic specialist where young snails are habitat specialists and adult snails are habitat generalists. Temperature was significantly higher and relative humidity significantly lower in stunted S. alterniflorathan in S. patens. These data suggest that thermal and desiccation stress restricted young snails to S. patens habitat, which has high stem density and a layer of thatch that protects snails from environmental stress. Other authors predict that if salt marshes in the northeast U.S. are unable to migrate landward, sea level rise will eliminate S. patenshabitats. We suggest that if a salt marsh loses its S. patens habitats, it will also lose its coffee bean snails. Our results demonstrate the need to consider individual life stages when determining a species’ vulnerability to global change
Validation of the Equine Behaviour Assessment and Research Questionnaire (E-BARQ): A new survey instrument for exploring and monitoring the domestic equine triad
Creation of a CIP Method for the Heat Exchangers at Rolls-Royce
Rolls-Royce produces various engines which must be tested prior to their distribution to ensure a high-quality product. The manufacturing plant contains four test cells where the engines can be subjected to high levels of torque and extreme temperatures. A heat exchanger is necessary in this testing system and over time, unwanted waste accumulates on the system’s plates. The team is tasked with developing and implementing a system mounted on a mobile cart which can provide data to determine whether the plates need to be cleaned. For this cleaning system to work, it must fully saturate the heat exchanger in cleaning solution, making the choice of pump important to the planning process. Additionally, the pump must be able to handle liquid containing silt and other debris and possess a maximum flow rate allowing the plates to be saturated. The pump must have four connection points to the heat exchanger system, and the fitting nozzle to control the flow rate of the cleaning solution into the heat exchanger. The cleaning solution for the system must be strong enough to clean the waste from the heat exchanger, yet weak enough to not corrode the plates. Additionally, some cleaning solutions have standards regarding storage and disposal, which have considerable influence on the selection of an acceptable solution. The final design incorporates a workable pump, a suitable solution, and the supporting materials needed to sustain the system. Implementation of the design will include pressure testing and a cleaning system that will improve the life span and efficiency of the heat exchanger in each test cell
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