250 research outputs found
The Biocompatibility of Various Dental Materials
Dentistry is a continuously evolving field with new materials and technologies constantly innovated. The oral cavity presents a harsh environment in which restorative and implant materials must be able to withstand. Aside for meeting the appropriate physical and chemical standards, it is important that dental materials be biocompatible. Biocompatibility relates to the material’s ability to function in the body without causing harm to living tissue. It is necessary to analyze the materials being used and determine whether they interact with the body in a detrimental manner. This will enable dental professionals to choose the most beneficial material to utilize for patient safety and overall health
A Data-Driven Approach to Appraisal and Selection at a Domain Data Repository
Social scientists are producing an ever-expanding volume of data, leading to questions about appraisal and selection of content given finite resources to process data for reuse. We analyze users’ search activity in an established social science data repository to better understand demand for data and more effectively guide collection development. By applying a data-driven approach, we aim to ensure curation resources are applied to make the most valuable data findable, understandable, accessible, and usable. We analyze data from a domain repository for the social sciences that includes over 500,000 annual searches in 2014 and 2015 to better understand trends in user search behavior. Using a newly created search-to-study ratio technique, we identified gaps in the domain data repository’s holdings and leveraged this analysis to inform our collection and curation practices and policies. The evaluative technique we propose in this paper will serve as a baseline for future studies looking at trends in user demand over time at the domain data repository being studied with broader implications for other data repositories.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145607/1/document.pd
Coordinating IBL and non-IBL Calculus II
Increasing amounts of research support the efficacy of inquiry and projects based learning. However, teaching via inquiry can be challenging for an individual instructor to adopt in a highly coordinated environment where a course is taught by multiple instructors, and all sections are expected to follow a common syllabus and take a common final exam. In this paper, we describe our efforts to make space for an inquiry approach to teaching calculus within this constrained environment where the new approach is not adopted by all instructors. Our efforts started with the collection, adaption and development of materials to cover the topics already defined for the course. We piloted our materials with a small group of instructors in the first semester and then opened up the materials to other instructors in subsequent semesters. We have now implemented this method over the past four semesters. Through this process we have shown that the integration of inquiry methods and projects within the pedagogy of individual instructors can be effective, but efforts should be taken to ensure the timing of instruction and coverage of materials is comparable to the efforts of colleagues teaching via lecture methods
Ground-truthing daily and lunar patterns of coral reef fish call rates on a US Virgin Island reef
© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ferguson, S., Jensen, F., Hyer, M., Noble, A., Apprill, A., & Mooney, T. Ground-truthing daily and lunar patterns of coral reef fish call rates on a US Virgin Island reef. Aquatic Biology, 31, (2022): 77–87, https://doi.org/10.3354/ab00755.Coral reefs comprise some of the most biodiverse habitats on the planet. These ecosystems face a range of stressors, making quantifying community assemblages and potential changes vital to effective management. To understand short- and long-term changes in biodiversity and detect early warning signals of decline, new methods for quantifying biodiversity at scale are necessary. Acoustic monitoring techniques have proven useful in observing species activities and biodiversity on coral reefs through aggregate approaches (i.e. energy as a proxy). However, few studies have ground-truthed these acoustic analyses with human-based observations. In this study, we sought to expand these passive acoustic methods by investigating biological sounds and fish call rates on a healthy reef, providing a unique set of human-confirmed, labeled acoustic observations. We analyzed acoustic data from Tektite Reef, St. John, US Virgin Islands, over a 2 mo period. A subset of acoustic files was manually inspected to identify recurring biotic sounds and quantify reef activity throughout the day. We found a high variety of acoustic signals in this soundscape. General patterns of call rates across time conformed to expectations, with dusk and dawn showing important and significantly elevated peaks in soniferous fish activity. The data reflected high variability in call rates across days and lunar phases. Call rates did not correspond to sound pressure levels, suggesting that certain call types may drive crepuscular trends in sound levels while lower-level critical calls, likely key for estimating biodiversity and behavior, may be missed by gross sound level analyses.This research was funded by the National Science Foundation Biological Oceanography award 1536782. The experiments were conducted under National Park Service Scientific Research and Collecting Permits VIIS-2016-SCI-0017-20, and we thank the Park staff for their support
Ozonation of a recirculating rainbow trout culture system I. Effects on bacterial gill disease and heterotrophic bacteria
AbstractOzone was added to water in a recirculating rainbow trout (Oncorhynchus mykiss) culture system just before it entered the culture tanks in an attempt to reduce the numbers of heterotrophic bacteria in system water and on trout gills, and to prevent bacterial gill disease (BGD) in newly stocked fingerlings. During four 8-week trials, ozone was added to the system at a rate of 0.025 or 0.036–0.039 kg ozone/kg feed fed. In the control, where no ozone was added, and in previously published research, BGD outbreaks occurred within two weeks of stocking, and these outbreaks generally required three to four chemotherapeutant treatments to prevent high mortality. In three of four trials where ozone was added to the system, BGD outbreaks were prevented without chemical treatments, but the causative bacterium, Flavobacterium branchiophilum, still colonized gill tissue. The one ozone test where BGD outbreaks required two chemical treatments coincided with a malfunction of the ozone generator. Although ozonation did reduce BGD mortality, it failed in all trials to produce more than a one log10 reduction in numbers of heterotrophic bacteria in the system water or on gill tissue. Failure of the ozone to lower numbers of heterotrophic bacteria or to prevent the causative BGD bacterium from occurring on gills was attributed to the short exposure time to ozone residual (35 s contact chamber) and rapid loss of oxidation caused by levels of total suspended solids. Rationale for ozone's success at preventing BGD mortalities are not fully understood but may in part be due to improved water quality. Use of the lower ozone dosing rate (0.025 kg ozone/kg feed) appeared to provide the same benefits as the higher dosing rate (0.036–0.039 kg ozone/kg feed fed); however, the lower ozone dosing rate was less likely to produce a toxic ozone residual in the culture tank and would also reduce ozone equipment capital and operating costs
Host allometry influences the evolution of parasite host-generalism: theory and meta-analysis
Parasites vary widely in the diversity of hosts they infect: some parasite species are specialists - infecting just a single host species, while others are generalists, capable of infecting many. Understanding the factors that drive parasite host-generalism is of basic biological interest, but also directly relevant to predicting disease emergence in new host species, identifying parasites that are likely to have unidentified additional hosts, and assessing transmission risk. Here, we use mathematical models to investigate how variation in host body size and environmental temperature affect the evolution of parasite host-generalism. We predict that parasites are more likely to evolve a generalist strategy when hosts are large-bodied, when variation in host body size is large, and in cooler environments. We then explore these predictions using a newly updated database of over 20,000 fish-macroparasite associations. Within the database we see some evidence supporting these predictions, but also highlight mismatches between theory and data. By combining these two approaches, we establish a theoretical basis for interpreting empirical data on parasites' host specificity and identify key areas for future work that will help untangle the drivers of parasite host-generalism
Membrane association and release of wild-type and pathological tau from organotypic brain slice cultures:Tau release from brain slice cultures
Identifying risk factors for L'Hermitte's sign after IMRT for head and neck cancer.
BACKGROUND
L’Hermitte’s sign (LS) after chemoradiotherapy for head and neck cancer appears related to higher spinal cord doses. IMRT plans limit spinal cord dose, but the incidence of LS remains high.
METHODS
117 patients treated with TomoTherapy™ between 2008 and 2015 prospectively completed a side-effect questionnaire (VoxTox Trial Registration: UK CRN ID 13716). Baseline patient and treatment data were collected. Radiotherapy plans were analysed; mean and maximum spinal cord dose and volumes receiving 10, 20, 30 and 40 Gy were recorded. Dose variation across the cord was examined. These data were included in a logistic regression model.
RESULTS
42 patients (35.9%) reported LS symptoms. Concurrent weekly cisplatin did not increase LS risk (p = 0.70, OR = 1.23 {95%CI 0.51 – 2.34}). Of 13 diabetic participants (9 taking metformin), only 1 developed LS (p = 0.025, OR = 0.13 {95%CI 0.051 – 3.27}). A refined binary logistic regression model showed that patients receiving unilateral radiation (p = 0.019, OR = 2.06 {95%CI 0.15 – 0.84}) were more likely to develop LS. Higher V40Gy (p = 0.047, OR = 1.06 {95%CI 1.00 – 1.12}), and younger age (mean age 56.6 vs 59.7, p = 0.060, OR = 0.96 {95%CI 0.92 – 1.00}) were associated with elevated risk of LS, with borderline significance.
CONCLUSIONS
In this cohort, concomitant cisplatin did not increase risk, and LS incidence was lower in diabetic patients. Patient age and dose gradients across the spinal cord may be important factors
Clinically unnecessary and avoidable emergency health service use for epilepsy: A survey of what English services are doing to reduce it
PurposeEpilepsy is associated with costly unplanned health service use. The UK's National Audits of Seizure Management in Hospital found use was often clinically unnecessary, avoidable and typically led to little benefit for epilepsy management. We systematically identified how services have responded to reduce such use.MethodsWe invited England's ambulance services, neuroscience and neurology centres and a random sample of Emergency Departments (EDs) to complete a survey. It asked what innovations they (or services they worked with) had made in the past 5 years or were making, the priority afforded to them, user involvement, what comprised usual practice, and barriers to change.Results72/87 of invited (82.8 %) services responded. EDs ascribed less priority to reducing emergency hospital use for epilepsy and convulsions, than other service types. Overall, 60 % of services reported a change(s) and/or were planning one. Neurology/neuroscience sites (93.8 %) were most likely to report change; EDs (15.4 %) least likely. Eleven types of change were identified; 5 sought to promote proactive epilepsy care and avert the need for emergency care; 3 focused on the care received from emergency services; and 3 focused on follow-up care ED attendees received. Most were for those with established, rather than new epilepsy and targeted known limitations to current care provision.ConclusionReducing emergency hospital use by PWE is a high priority for most health services in England and a number of new services have been developed. However, they have not been consistently implemented and innovation is lacking in some areas of care
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