75 research outputs found
Beyond the Tutorial: Complex Content Models in Fedora 3
4th International Conference on Open RepositoriesThis presentation was part of the session : Fedora User Group PresentationsDate: 2009-05-21 08:30 AM – 10:00 AMThe University of Wisconsin Digital Collections Center recently began a pilot project to create a digital collection of learning objects stored in a Fedora 3.1 repository. This pilot project is the proof-of-concept of many ideas and discussions, extending back for over five years, concerning the problem of storing, searching, and retrieving heterogeneous objects and object types, linked together in complex relations, in a way that is loosely coupled with front-end user display applications. During the course of this presentation, we will describe the issues we've confronted implementing increasingly rich digital collections over the past decade (including some real-life examples of complex digital objects), models we have developed with to resolve many of those issues, and how we have started implementing those models in Fedora 3.1, using the new Content Model functionality
Clemson’s Past Digitized: The Future of Archival Access
Libraries are at the forefront of creating rich quality metadata to ensure a future where communities access, learn, and understand their shared histories. The Metadata and Monographic Resources Team (MMRT) is tasked with describing and providing access points to Clemson Libraries’ Digital Collections. Consisting of digitized historic materials from Special Collections and Archives, Digital Collections provides a globally accessible avenue for our communities to explore Clemson’s past. Metadata decisions made by MMRT affect how community members discover, access, and use these materials. This poster covers metadata challenges and decisions we made to improve access to one digital collection, Clemson University Historical Images
Describing Historical Images: Improving Access to Digital Collections with Local Subjects
Libraries are at the forefront of creating rich quality metadata to ensure communities can access, learn, and understand their shared histories. The Metadata and Monographic Resources Team (MMRT) is tasked with describing and providing access points to Clemson Libraries’ Digital Collections. Metadata decisions made by MMRT affect how community members discover, access, and use these materials. Photographic images, in particular, pose challenges if they lack descriptive information or historical context. If descriptions are provided, they often align with the historically white male majority, naming high level individuals and leaving out minority and marginalized peoples.
This poster covers challenges and decisions MMRT made to improve inclusive access to the Clemson University Historical Images by harnessing the power of local subject headings. This includes steps metadata specialists take to research image content, identify knowledge gaps, and create and apply new local subjects. Hard questions needed to be answered. For example, how do we normalize and control our local subjects to ensure consistent application? How detailed of a description do we provide to contextualize an image for researchers? Our current goal is to create a sustainable descriptive process that is consistently applied across a collection to support researcher needs. This poster will also discuss future hopes and goals, such as creating a globally accessible, shareable, and reusable local subject vocabulary for institutions beyond Clemson. The local subject approach could be useful for any type of library or cultural heritage institution looking to digitize and describe their image collections
The Effect of Kipping on the Performance of a Pull-up
The high prevalence of obesity and sedentary lifestyle contribute to the growing burden of health care costs, incidence of disease, and mortality, making a lifestyle that includes regular physical activity increasingly important. Low intensity resistance training has been studied as a possible intervention to increase physical activity in inactive individuals. To determine the effects of a weighted vest treatment (WV) on steady state VO2, O2 deficit, VO2max, body mass index (BMI), and resting blood pressure (RBP). Fourteen college age women participated in a 4 week trial and completed both pre and posttest evaluations. These evaluations included a submaximal exercise bout, a maximal graded exercise test, determination of BMI, and measurement of RBP. Seven participants wore a weighted vest, fitted with 10% of their body weight, during normal daily activities for a minimum of 10 hours a day, 5 days each week. The remaining 7 participants served as a control group. ANCOVAs, with pretest measures serving as the covariates, were conducted to determine the effect of WV on posttest responses. Mean (sd) pre-test O2 deficit values were 0.64 (0.18) and 0.68 (0.18) for the control and WV groups, respectively. Mean (sd) post-test O2 deficit values were 0.62 (0.15) and 0.38 (0.17) for the control and WV groups, respectively. Results of the ANCOVA revealed a significant effect of WV on O2 deficit with O2 deficit values being lower following WV (F(1,11) = 7.30, p = 0.02). Further, WV accounted for about 40% of the change observed in posttest O2 deficit values (ηp2 = 0.40). However, no significant effect of WV was seen on steady state VO2, VO2 max, BMI, or RBP. WV resulted in lower O2 deficit values suggesting that it could elicit training effects related to improved aerobic function. Possible explanations for the lack of effects on other variables could be related to the limitations imposed by the relatively small sample size and trial length. Future studies designed with larger sample sizes and longer trial periods might prove more effective in evaluating the effect of WV on eliciting health related benefits
Leaf-litter stoichiometry is affected by streamwater phosphorus concentrations and litter type
The stoichiometric ratios of organisms and their food resources can influence C and nutrient
dynamics in aquatic ecosystems. Several investigators have quantified linkages between nutrient enrichment and consumer stoichiometry for stream detritivores, but very few have systematically quantified the effect of P enrichment on leaf-litter stoichiometry. Here, we examine the potential stoichiometric changes of 2 species of leaf litter subjected to varying levels of P enrichment in laboratory
microcosms and mixed species across a natural P gradient of streams in the Ozark Highlands Region, Arkansas, USA. Leaf-litter %P content increased and C:P ratios decreased with increasing levels of P enrichment and with increasing lability of the leaf species. In the laboratory study, C:P of maple and oak
leaves in the control treatment was ,2500, whereas this ratio decreased to 500 and 1000 in the high-P treatments, respectively. Total P (TP) was inversely related to leaf-litter C:P along the natural P gradient of streams in the Ozarks. Our results add to the growing body of information on the potential bottom-up
effects of anthropogenic nutrient loading in streams and the influence of water-column nutrients and leaf quality on this response
Mobility and bioavailability of sediment phosphorus in urban stormwater ponds
© 2019. American Geophysical Union. All Rights Reserved. Stormwater ponds can serve as retention hotspots for phosphorus (P) moving out of the urban environment. This retention may be reduced by P speciation that reduces the bioavailability of P to primary producers and alters its mobility in sediments. Here we examined the mobility and fate of dissolved P in urban stormwater ponds with a set of complementary field measurements and short-term laboratory and field experiments. We measured the types and amount of P in water column and sediments of urban stormwater ponds. We further assessed the mobility of different P types in pond sediments in the field and rates of P release from sediment cores maintained under laboratory conditions. Finally, we assessed P uptake rates by pond algal communities using short-term bioassay experiments. We found that dissolved organic P was highly prevalent in urban pond water and sediments and that this type of P was mobile within sediments and could be released under high or low O 2 conditions. We also found highly variable P demand by algae among stormwater ponds and that algal growth responses to P was correlated to water column N:P ratios. Altogether, our results indicate an important role for organic phosphorus cycling in urban stormwater ponds, which likely constrains the overall retention efficiency in these aquatic ecosystems
Understanding variation in salamander ionomes: A nutrient balance approach
Ecological stoichiometry uses information on a few key biological elements (C, N, and P) to
explain complex ecological patterns. Although factors driving variation in these elements are
well-established, expanding stoichiometric principles to explore dynamics of the many other
essential elements comprising biological tissues (i.e., the ionome) is needed to determine their
metabolic relationships and better understand biological control of elemental flows through
ecosystems.
2. In this paper, we report observations of ionomic variation in two species of salamander
(Ambystoma opacum and A. talpoideum) across ontogenic stages using specimens from
biological collections of two wetlands sampled over a 30-year period. This unique data set
allowed us to explore the extent of ionomic variation between species, among ontogenic stages,
between sites, and through time.
3. We found species- and to a lesser extent site-specific differences in C, N, and P along with 13
other elements forming salamander ionomes but saw no evidence of temporal changes.
Salamander ionomic composition was most strongly related to ontogeny with relatively higher
concentrations of many elements in adult males (i.e., Ca, P, S, Mg, Zn, and Cu) compared to
metamorphic juveniles, which had greater amounts of C, Fe, and Mn.
4. In addition to patterns of individual elements, covariance among elements was used to
construct multi-elemental nutrient balances, which revealed differences in salamander elemental
composition between species and sites and changes in elemental proportions across ontogenic
development. These multi-elemental balances distinguished among species-site-ontogenic stage
groups better than using only C, N, and P.
5. Overall, this study highlights the responsiveness of consumer ionomes to life-history and
environmental variation while reflecting underlying relationships among elements tied to
biological function. As such, ionomic studies can provide important insights into factors shaping
consumer elemental composition and for predicting how these changes might affect higher-order
ecological processes
Relationships among nutrient enrichment, detritus quality and quantity, and large-bodied shredding insect community structure
This is a post-peer-review, pre-copyedit version of an article published in Hydrobiologia. The final authenticated version is available online at: https://doi.org/10.1007/s10750-015-2208-2Anthropogenic nutrient enrichment of
forested headwater streams can enhance detrital quality, decrease standing stocks, and alter the community structure of detrivorous insects, reducing nutrient retention and decreasing ecosystem functioning. Our objective was to determine if stoichiometric
principles could be used to predict genus-specific shifts in shredding insect abundance and biomass across a dissolved nutrient and detritus food quality/quantity gradient. Detritus, insect, and water samples were collected from 12 Ozark Highland headwater
streams. Significant correlations were found between stream nutrients and detrital quality but not quantity. Abundance and biomass responses of four out of five tested genera were accurately predicted by consumerresource stoichiometric theory. Low carbon:phosphorus (C:P) shredders responded positively to increased total phosphorus and/or food quality, and high C:P shredders exhibited neutral or negative responses to these variables. Genus-specific declines were
correlated with decreased overall biomass in shredder assemblages, potentially causing disruptions in nutrient flows to higher level consumers with nutrient enrichment. This work provides further evidence that elevated nutrients may negatively impact shredding
insect communities by altering the stoichiometry of detritus–detritivore interactions. A better understanding of stoichiometric mechanisms altering macroinvertebrate populations is needed to help inform water quality criteria for the management of headwater streams
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