144 research outputs found

    Teaching The Elusive Skill Set: Concept and Content

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    The boundaries of what art and design curricula cover expand with the scope of contemporary art. Content and concept are now as important as craft and technique have been traditionally. An emerging challenge for art educators is to teach idea development with the depth, breadth, and comprehensibility that one teaches the craft and technique of specific media. The physical skills associated with making work in a particular material or with a certain technical process seem more concrete and understandable than the cognitive and temporal skills and methods associated with idea development. This differential is likely based on the observability of processes of the hand and the relative invisibility of mental and emotional process. How can we effectively teach students to craft with great facility in this less tangible realm of ideas and creative content? This panel of presenters will discuss strategies for developing and delivering concept development and visual content communication coursework. How can we teach the more elusive, yet vital, artistic talents of communication through concept, content, and context? The panel will investigate methods for teaching courses with the objective of building the foundational skills of creative concept development and visual content communication in a studio art setting. The panel will offer insight into the following two questions: 1) What things should one consider when developing coursework for teaching rich content development? 2) In a post media centric course format, how can we meaningfully evaluate quantity and quality of communication in student work

    Effects of ocean acidification on marine dissolved organic matter are not detectable over the succession of phytoplankton blooms

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    Marine dissolved organic matter (DOM) is one of the largest active organic carbon reservoirs on Earth, and changes in its pool size or composition could have a major impact on the global carbon cycle. Ocean acidification is a potential driver for these changes because it influences marine primary production and heterotrophic respiration. We simulated ocean acidification as expected for a “business-as-usual” emission scenario in the year 2100 in an unprecedented long-term mesocosm study. The large-scale experiments (50 m3 each) covered a full seasonal cycle of marine production in a Swedish Fjord. Five mesocosms were artificially enriched in CO2 to the partial pressure expected in the year 2100 (900 μatm), and five more served as controls (400 μatm). We applied ultrahigh-resolution mass spectrometry to monitor the succession of 7360 distinct DOM formulae over the course of the experiment. Plankton blooms had a clear effect on DOM concentration and molecular composition. This succession was reproducible across all 10 mesocosms, independent of CO2 treatment. In contrast to the temporal trend, there were no significant differences in DOM concentration and composition between present-day and year 2100 CO2 levels at any time point of the experiment. On the basis of our results, ocean acidification alone is unlikely to affect the seasonal accumulation of DOM in productive coastal environments

    Universal molecular structures in natural dissolved organic matter

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    Natural dissolved organic matter (DOM) comprises a broad range of dissolved organic molecules in aquatic systems and is among the most complex molecular mixtures known. Here we show, by comparing detailed structural fingerprints of individual molecular formulae in DOM from a set of four marine and one freshwater environments, that a major component of DOM is molecularly indistinguishable in these diverse samples. Molecular conformity was not only apparent by the co-occurrence of thousands of identical molecular formulae, but also by identical structural features of those isomers that collectively represent a molecular formula. The presence of a large pool of compounds with identical structural features in DOM is likely the result of a cascade of degradation processes or common synthetic pathways that ultimately lead to the formation of a universal background, regardless of origin and history of the organic material. This novel insight impacts our understanding of long-term turnover of DOM as the underlying mechanisms are possibly universal

    Chiropractic treatment of older adults with neck pain with or without headache or dizziness: Analysis of 288 Australian chiropractors' self-reported views

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    © 2019 The Author(s). Background: Neck pain is a leading cause of individual and societal burden worldwide, affecting an estimated 1 in 5 people aged 70 years and older. The nature and outcomes of chiropractic care for older adults with neck pain, particularly those with co-morbid headaches, remains poorly understood. Therefore, we sought to ascertain: What proportion of Australian chiropractors' caseload comprises older adults with neck pain (with or without headache); How are these conditions treated; What are the reported outcomes? Methods: An online survey examining practitioner and practice characteristics, clinical patient presentations, chiropractic treatment methods and outcomes, and other health service use, was distributed to a random nationally representative sample of 800 Australian chiropractors. Quantitative methods were used to analyze the data. Results: Two hundred eighty-eight chiropractors (response rate = 36%) completed the survey between August and November 2017. Approximately one-third (M 28.5%, SD 14.2) of the chiropractors' patients were older adults (i.e. aged ≥65 years), of which 45.5% (SD 20.6) presented with neck pain and 31.3% (SD 20.3) had co-morbid headache. Chiropractors reported to combine a range of physical and manual therapy treatments, exercises and self-management practices in their care of these patients particularly: manipulation of the thoracic spine (82.0%); activator adjustment of the neck (77.3%); and massage of the neck (76.5%). The average number of visits required to resolve headache symptoms was reported to be highest among those with migraine (M 11.2, SD 8.8). The majority of chiropractors (57.3%) reported a moderate response to treatment in reported dizziness amongst older adults with neck pain. Approximately 82% of older adult patients were estimated to use at least one other health service concurrently to chiropractic care to manage their neck pain. Conclusion: This is the first known study to investigate chiropractic care of older adults living with neck pain. Chiropractors report using well-established conservative techniques to manage neck pain in older adults. Our findings also indicate that this target group of patients may frequently integrate chiropractic care with other health services in order to manage their neck pain. Further research should provide in-depth investigation of older patients' experience and other patient-reported outcomes of chiropractic treatment

    Ocean Acidification Experiments in Large-Scale Mesocosms Reveal Similar Dynamics of Dissolved Organic Matter Production and Biotransformation

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    Dissolved organic matter (DOM) represents a major reservoir of carbon in the oceans. Environmental stressors such as ocean acidification (OA) potentially affect DOM production and degradation processes, e.g., phytoplankton exudation or microbial uptake and biotransformation of molecules. Resulting changes in carbon storage capacity of the ocean, thus, may cause feedbacks on the global carbon cycle. Previous experiments studying OA effects on the DOM pool under natural conditions, however, were mostly conducted in temperate and coastal eutrophic areas. Here, we report on OA effects on the existing and newly produced DOM pool during an experiment in the subtropical North Atlantic Ocean at the Canary Islands during an (1) oligotrophic phase and (2) after simulated deep water upwelling. The last is a frequently occurring event in this region controlling nutrient and phytoplankton dynamics. We manipulated nine large-scale mesocosms with a gradient of pCO2 ranging from ~350 up to ~1,030 μatm and monitored the DOM molecular composition using ultrahigh-resolution mass spectrometry via Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). An increase of 37 μmol L−1 DOC was observed in all mesocosms during a phytoplankton bloom induced by simulated upwelling. Indications for enhanced DOC accumulation under elevated CO2 became apparent during a phase of nutrient recycling toward the end of the experiment. The production of DOM was reflected in changes of the molecular DOM composition. Out of the 7,212 molecular formulae, which were detected throughout the experiment, ~50% correlated significantly in mass spectrometric signal intensity with cumulative bacterial protein production (BPP) and are likely a product of microbial transformation. However, no differences in the produced compounds were found with respect to CO2 levels. Comparing the results of this experiment with a comparable OA experiment in the Swedish Gullmar Fjord, reveals similar succession patterns for individual compound pools during a phytoplankton bloom and subsequent accumulation of these compounds were observed. The similar behavior of DOM production and biotransformation during and following a phytoplankton bloom irrespective of plankton community composition and CO2 treatment provides novel insights into general dynamics of the marine DOM pool

    Enhanced transfer of organic matter to higher trophic levels caused by ocean acidification and its implications for export production : A mass balance approach

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    Ongoing acidification of the ocean through uptake of anthropogenic CO2 is known to affect marine biota and ecosystems with largely unknown consequences for marine food webs. Changes in food web structure have the potential to alter trophic transfer, partitioning, and biogeochemical cycling of elements in the ocean. Here we investigated the impact of realistic end-of-the-century CO2 concentrations on the development and partitioning of the carbon, nitrogen, phosphorus, and silica pools in a coastal pelagic ecosystem (Gullmar Fjord, Sweden). We covered the entire winter-to-summer plankton succession (100 days) in two sets of five pelagic mesocosms, with one set being CO2 enriched (similar to 760 mu atm pCO(2)) and the other one left at ambient CO2 concentrations. Elemental mass balances were calculated and we highlight important challenges and uncertainties we have faced in the closed mesocosm system. Our key observations under high CO2 were: (1) A significantly amplified transfer of carbon, nitrogen, and phosphorus from primary producers to higher trophic levels, during times of regenerated primary production. (2) A prolonged retention of all three elements in the pelagic food web that significantly reduced nitrogen and phosphorus sedimentation by about 11 and 9%, respectively. (3) A positive trend in carbon fixation (relative to nitrogen) that appeared in the particulate matter pool as well as the downward particle flux. This excess carbon counteracted a potential reduction in carbon sedimentation that could have been expected from patterns of nitrogen and phosphorus fluxes. Our findings highlight the potential for ocean acidification to alter partitioning and cycling of carbon and nutrients in the surface ocean but also show that impacts are temporarily variable and likely depending upon the structure of the plankton food web.Peer reviewe

    Character and environmental lability of cyanobacteria-derived dissolved organic matter

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    Autotrophic dissolved organic matter (DOM) is central to the carbon biogeochemistry of aquatic systems, and the full complexity of autotrophic DOM has not been extensively studied, particularly by high-resolution mass spectrometry (HRMS). Terrestrial DOM tends to dominate HRMS studies in freshwaters due to the propensity of such compounds to ionize by negative mode electrospray, and possibly also because ionizable DOM produced by autotrophy is decreased to low steady-state concentrations by heterotrophic bacteria. In this study, we investigated the character of DOM produced by the widespread cyanobacteriaMicrocystis aeruginosausing high-pressure liquid chromatography-electrospray ionization-high-resolution mass spectrometry.M. aeruginosaproduced thousands of detectable compounds in axenic culture. These compounds were chromatographically resolved and the majority were assigned to aliphatic formulas with a broad polarity range. We found that the DOM produced byM. aeruginosawas highly susceptible to removal by heterotrophic freshwater bacteria, supporting the hypothesis that this autotroph-derived organic material is highly labile and accordingly only seen at low concentrations in natural settings

    Eutrophication and acidification: Do they induce changes in the dissolvedorganic matter dynamics in the coastal Mediterranean Sea?

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    Original research paperTwo mesocosms experiments were conducted in winter 2010 and summer 2011 to examine how increased pCO2and/or nutrient concentrations potentially perturbate dissolved organic matter dynamics in natural microbialassemblages. Thefluorescence signals of protein- and humic-like compounds were used as a proxy for labileand non-labile material, respectively, while the evolution of bacterial populations, chlorophylla(Chla) anddissolved organic carbon (DOC) concentrations were used as a proxy for biological activity. For both seasons,the presence of elevated pCO2did not cause any significant change in the DOC dynamics (p-valueb0.05). Theconditions that showed the greatest changes in prokaryote abundances and Chlacontent were those amendedwith nutrients, regardless of the change in pH. The temporal evolution offluorophores and optical indices re-vealed that the degree of humification of the organic molecules and their molecular weight changed significantlyin the nutrient-amended treatment. The generation of protein-like compounds was paired to increases in theprokaryote abundance, being higher in the nutrient-amended tanks than in the control. Different patterns inthe magnitude and direction of the generation of humic-like molecules suggested that these changes dependedon initial microbial populations and the availability of extra nutrient inputs. Based on our results, it is expected that in the future projected coastal scenarios the eutrophication processes will favor the transformations of labile and recalcitrant carbon regardless of changes in pCO2.MINECO, European Union, Generalitat de Catalunya, CSICVersión del editor3,25

    Influence of Ocean Acidification on a Natural Winter-to-Summer Plankton Succession : First Insights from a Long-Term Mesocosm Study Draw Attention to Periods of Low Nutrient Concentrations

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    Every year, the oceans absorb about 30% of anthropogenic carbon dioxide (CO2) leading to a re-equilibration of the marine carbonate system and decreasing seawater pH. Today, there is increasing awareness that these changes-summarized by the term ocean acidification (OA)-could differentially affect the competitive ability of marine organisms, thereby provoking a restructuring of marine ecosystems and biogeochemical element cycles. In winter 2013, we deployed ten pelagic mesocosms in the Gullmar Fjord at the Swedish west coast in order to study the effect of OA on plankton ecology and biogeochemistry under close to natural conditions. Five of the ten mesocosms were left unperturbed and served as controls (similar to 380 mu atm pCO(2)), whereas the others were enriched with CO2-saturated water to simulate realistic end-of-the-century carbonate chemistry conditions (mu 760 mu atm pCO(2)). We ran the experiment for 113 days which allowed us to study the influence of high CO2 on an entire winter-to-summer plankton succession and to investigate the potential of some plankton organisms for evolutionary adaptation to OA in their natural environment. This paper is the first in a PLOS collection and provides a detailed overview on the experimental design, important events, and the key complexities of such a "long-term mesocosm" approach. Furthermore, we analyzed whether simulated end-of-the-century carbonate chemistry conditions could lead to a significant restructuring of the plankton community in the course of the succession. At the level of detail analyzed in this overview paper we found that CO2-induced differences in plankton community composition were non-detectable during most of the succession except for a period where a phytoplankton bloom was fueled by remineralized nutrients. These results indicate: (1) Long-term studies with pelagic ecosystems are necessary to uncover OA-sensitive stages of succession. (2) Plankton communities fueled by regenerated nutrients may be more responsive to changing carbonate chemistry than those having access to high inorganic nutrient concentrations and may deserve particular attention in future studies.Peer reviewe
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