37 research outputs found
Cutaneous Blood Flow and Percutaneous Absorption: A Quantitative Analysis Using a Laser Doppler Velocimeter and a Blood Flow Meter
Cutaneous blood flow has been directly quantitated in vivo for the first time without animal death utilizing the rat skin sandwich flap. This was accomplished by conducting experiments that made a direct correlation between two instruments: a laser Doppler velocimeter and an electromagnetic blood flow meter. Data demonstrate that the correlation between these two instruments is high and reproducible (r = 0.96) with a small (1.3%) coefficient of variation. Blood flow to skin in the unmanipulated state varies from 0.7 to 1.2 mls/min in an anesthetized rat. Application of the blood flow correlation to the determination of percutaneous absorption of caffeine across human skin and benzoic acid across rat skin demonstrates that assuming cutaneous blood flow is a particular value day to day in any skin type results in an apparent wide range of total compound absorbed across that skin on independent occasions. Utilizing actual blood flow measurements to calculate the amount of chemical absorbed reduces the range of variability in the total amount of chemical absorbed and provides a more accurate knowledge of events occurring during a particular time of the absorption process. Quantitation of cutaneous blood flow will be useful in physiologic and pharmacologic studies where actual cutaneous blood flow is likely to be important to the processes studied, e.g., delivery of drug to skin, metabolism within the skin, and disposition of drug to blood and skin following topical drug application
Ecology of the Invasive Red Alga Gracilaria salicornia (Rhodophyta) on O'ahu, Hawai'i
The red alga Gracilaria salicornia (C. Agardh) E. Y. Dawson was introduced
intentionally to two reefs on O'ahu, Hawai'i, in the 1970s for experimental
aquaculture for the agar industry. Some 30 yr later, this species has
spread from the initial sites of introduction and is now competing with native
marine flora and fauna. The goals of this study were to quantify various aspects
of G. salicornia ecology in Hawai'i in an effort to develop control or eradication
tools. Experimental plots were established to determine cover and biomass of G.
salicornia per square meter and to determine the amount of time and person
hours needed to remove G. salicornia from these plots. Substantial amounts of G.
salicornia become dislodged from the reef during large wave events and periodically
become deposited onto the beach in front of the Waikiki Aquarium. Algal
beach wash biomass was quantified and positive relationships were established
between swell height and the amount of algae that washed up onto the beach in
this location. We then quantified the ability of G. salicornia vegetative fragments
to regrow after desiccation to determine if algal biomass stranded on shore survives
the tidal cycle until being washed back out on the reef at high tide. Gracilaria
salicornia was remarkably resistant to temperature, salinity, and chemical
treatments examined as possible in situ control options. Herbivore preference
tests showed that a native Gracilaria species is consumed far more frequently
than the alien congener. Finally, large-scale community volunteer efforts were
organized to remove drifting G. salicornia fragments from the reef area in front
of the Waikiki Aquarium. Over 20,000 kg of alien algal fragments were removed
from this location in five 4-hr cleanup events. However, based on G. salicornia
growth rates, ability to fragment, physical tolerance, and low herbivory, it is
clear that a large-scale dedicated effort will be needed to control this invasive
species on Waikiki's reefs
Trends and Insights from Transportation Congestion Pricing Policy Research: A Bibliometric Analysis
Toll-based congestion pricing (CP) policies are increasingly implemented globally for alleviating road traffic congestion. Several interconnected factors affecting or induced by CP implementation include air quality/emissions, travel time, and road user safety. We sought to examine and characterize research output and patterns across several domains (e.g., health, policy acceptability) surrounding toll-based CP policies, in order to identify where research has focused and where gaps exist. We conducted a structured review and identified 2333 relevant publications, using semi-supervised and machine learning strategies combined with manual review. Annual publication counts peaked in 2015 (n = 122). Themes identified from title and abstract terms included policy implementation characteristics, advanced transportation modeling methods and approaches, and public perception and acceptability. Authorship networks indicated a lack of interdisciplinary research. Country analyses identified the US, China, and the UK as the most frequently represented countries, and underrepresentation from low-income countries. Findings indicate that research focused on specific road user types (e.g., pedestrians) and safety impacts, and equity considerations were relatively sparse compared to other topics (e.g., policy economics, public perception). Additional research on these critical topics is necessary to ensure that such policies are designed to promote positive and equitable effects on road user health and safety
High-throughput gene discovery in the rat
The rat is an important animal model for human diseases and is widely used in physiology. In this article we present a new strategy for gene discovery based on the production of ESTs from serially subtracted and normalized cDNA libraries, and we describe its application for the development of a comprehensive nonredundant collection of rat ESTs. Our new strategy appears to yield substantially more EST clusters per ESTs sequenced than do previous approaches that did not use serial subtraction. However, multiple rounds of library subtraction resulted in high frequencies of otherwise rare internally primed cDNAs, defining the limits of this powerful approach. To date, we have generated >200,000 3âČ ESTs from >100 cDNA libraries representing a wide range of tissues and developmental stages of the laboratory rat. Most importantly, we have contributed to âŒ50,000 rat UniGene clusters. We have identified, arrayed, and derived 5âČ ESTs from >30,000 unique rat cDNA clones. Complete information, including radiation hybrid mapping data, is also maintained locally at http://genome.uiowa.edu/clcg.html. All of the sequences described in this article have been submitted to the dbEST division of the NCBI
Unexpected diversity in socially synchronized rhythms of shorebirds
The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities with those of others, including potential mates, competitors, prey and predators. Individuals can temporally segregate their daily activities (for example, prey avoiding predators, subordinates avoiding dominants) or synchronize their activities (for example, group foraging, communal defence, pairs reproducing or caring for offspring). The behavioural rhythms that emerge from such social synchronization and the underlying evolutionary and ecological drivers that shape them remain poorly understood. Here we investigate these rhythms in the context of biparental care, a particularly sensitive phase of social synchronization where pair members potentially compromise their individual rhythms. Using data from 729 nests of 91 populations of 32 biparentally incubating shorebird species, where parents synchronize to achieve continuous coverage of developing eggs, we report remarkable within-and between-species diversity in incubation rhythms. Between species, the median length of one parent's incubation bout varied from 1-19 h, whereas period length-the time in which a parent's probability to incubate cycles once between its highest and lowest value-varied from 6-43 h. The length of incubation bouts was unrelated to variables reflecting energetic demands, but species relying on crypsis (the ability to avoid detection by other animals) had longer incubation bouts than those that are readily visible or who actively protect their nest against predators. Rhythms entrainable to the 24-h light-dark cycle were less prevalent at high latitudes and absent in 18 species. Our results indicate that even under similar environmental conditions and despite 24-h environmental cues, social synchronization can generate far more diverse behavioural rhythms than expected from studies of individuals in captivity. The risk of predation, not the risk of starvation, may be a key factor underlying the diversity in these rhythms.</p
Unexpected diversity in socially synchronized rhythms of shorebirds
The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment1, 2, 3, 4. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions1, 5, but free-living individuals have to temporally synchronize their activities with those of others, including potential mates, competitors, prey and predators6, 7, 8, 9, 10. Individuals can temporally segregate their daily activities (for example, prey avoiding predators, subordinates avoiding dominants) or synchronize their activities (for example, group foraging, communal defence, pairs reproducing or caring for offspring)6, 7, 8, 9, 11. The behavioural rhythms that emerge from such social synchronization and the underlying evolutionary and ecological drivers that shape them remain poorly understood5, 6, 7, 9. Here we investigate these rhythms in the context of biparental care, a particularly sensitive phase of social synchronization12 where pair members potentially compromise their individual rhythms. Using data from 729 nests of 91 populations of 32 biparentally incubating shorebird species, where parents synchronize to achieve continuous coverage of developing eggs, we report remarkable within- and between-species diversity in incubation rhythms. Between species, the median length of one parentâs incubation bout varied from 1â19âh, whereas period lengthâthe time in which a parentâs probability to incubate cycles once between its highest and lowest valueâvaried from 6â43âh. The length of incubation bouts was unrelated to variables reflecting energetic demands, but species relying on crypsis (the ability to avoid detection by other animals) had longer incubation bouts than those that are readily visible or who actively protect their nest against predators. Rhythms entrainable to the 24-h lightâdark cycle were less prevalent at high latitudes and absent in 18 species. Our results indicate that even under similar environmental conditions and despite 24-h environmental cues, social synchronization can generate far more diverse behavioural rhythms than expected from studies of individuals in captivity5, 6, 7, 9. The risk of predation, not the risk of starvation, may be a key factor underlying the diversity in these rhythms
Position paper: The potential role of optical biopsy in the study and diagnosis of environmental enteric dysfunction
Environmental enteric dysfunction (EED) is a disease of the small intestine affecting children and adults in low and middle income countries. Arising as a consequence of repeated infections, gut inflammation results in impaired intestinal absorptive and barrier function, leading to poor nutrient uptake and ultimately to stunting and other developmental limitations. Progress towards new biomarkers and interventions for EED is hampered by the practical and ethical difficulties of cross-validation with the gold standard of biopsy and histology. Optical biopsy techniques â which can provide minimally invasive or noninvasive alternatives to biopsy â could offer other routes to validation and could potentially be used as point-of-care tests among the general population. This Consensus Statement identifies and reviews the most promising candidate optical biopsy technologies for applications in EED, critically assesses them against criteria identified for successful deployment in developing world settings, and proposes further lines of enquiry. Importantly, many of the techniques discussed could also be adapted to monitor the impaired intestinal barrier in other settings such as IBD, autoimmune enteropathies, coeliac disease, graft-versus-host disease, small intestinal transplantation or critical care
We Built It, They All Came, Now What?
Background: Liaison librarians are often victims of their own successes. They strive to create embeddedness, and find there are not enough hours to accommodate all those who seek them out. Most liaisons are cognizant of the need to approach their roles strategically, but can find it difficult to carve aside the time needed to plan an approach that allows allow them to reach the largest number of their programs in the most effective way possible. This session will address how librarians at the University of North Carolina at Chapel Hill (UNC) Health Sciences Library (HSL) have strategized to create effective and streamlined liaison programs.
Description: UNC HSL liaison librarians have employed several approaches for greater efficiency: engagement with faculty to create more streamlined research assignments, curriculum mapping with skill scaffolding, team delivered drop-in âsearch clinicsâ for large classes, online assistance via Zoom, expanded subject guides, and team collaboration on instruction and research assistance. Librarians have also looked at tiered service models to reach the maximum number of users. When possible, class assignments are handled by targeted instruction, while masters papers, dissertations, and systematic reviews are handled with a combination of targeted instruction and consultations. Citation management and baseline reference questions are often answered by research assistants, and RAs have also been trained to offer classes in using citation management and Covidence classes. By requesting more embeddedness in classes with research assignments, librarian consultation time is available to assist those with more complex individualized research needs
Trends and Insights from Transportation Congestion Pricing Policy Research: A Bibliometric Analysis
Toll-based congestion pricing (CP) policies are increasingly implemented globally for alleviating road traffic congestion. Several interconnected factors affecting or induced by CP implementation include air quality/emissions, travel time, and road user safety. We sought to examine and characterize research output and patterns across several domains (e.g., health, policy acceptability) surrounding toll-based CP policies, in order to identify where research has focused and where gaps exist. We conducted a structured review and identified 2333 relevant publications, using semi-supervised and machine learning strategies combined with manual review. Annual publication counts peaked in 2015 (n = 122). Themes identified from title and abstract terms included policy implementation characteristics, advanced transportation modeling methods and approaches, and public perception and acceptability. Authorship networks indicated a lack of interdisciplinary research. Country analyses identified the US, China, and the UK as the most frequently represented countries, and underrepresentation from low-income countries. Findings indicate that research focused on specific road user types (e.g., pedestrians) and safety impacts, and equity considerations were relatively sparse compared to other topics (e.g., policy economics, public perception). Additional research on these critical topics is necessary to ensure that such policies are designed to promote positive and equitable effects on road user health and safety
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Evaluating nursing faculty's approach to information literacy instruction: a multi-institutional study
Objective: In 2018, the Association of College & Research Libraries (ACRL) Health Sciences Interest Group convened a working group to update the 2013 Information Literacy Competency Standards for Nursing to be a companion document to the 2016 Framework for Information Literacy in Higher Education. To create this companion document, the working group first needed to understand how nursing faculty approached information literacy (IL) instruction. Methods: The working group designed a survey that assessed how nursing faculty utilized IL principles in coursework and instruction. The survey consisted of nineteen mixed methods questions and was distributed to nursing faculty at eight institutions across the United States. Results: Most (79%) faculty indicated that they use a variety of methods to teach IL principles in their courses. While only 12% of faculty incorporated a version of the ACRL IL competencies in course design, they were much more likely to integrate nursing educational association standards. Faculty perceptions of the relevance of IL skills increased as the education level being taught increased. Conclusion: The integration of IL instruction into nursing education has mostly been achieved through using standards from nursing educational associations. Understanding these standards and understanding how faculty perceptions of the relevance of IL skills change with educational levels will guide the development of a companion document that librarians can use to collaborate with nurse educators to integrate IL instruction throughout nursing curriculums at course and program levels.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]