3,195 research outputs found
Replicability of data collected for empirical estimation of relative pollen productivity
The effects of repeated survey and fieldwork timing on data derived from a recently proposed standard field methodology for empirical estimation of relative pollen productivity (RPP) have been tested. Seasonal variations in vegetation and associated pollen assemblages were studied in three contrasting cultural habitat types; semi-natural ancient woodlands, lowland heaths, and unimproved, traditionally managed hay meadows. Results show that in woodlands and heathlands the standard method generates vegetation data with a reasonable degree of similarity throughout the field season, though in some instances additional recording of woodland canopy cover should be undertaken, and differences were greater for woodland understorey taxa than for arboreal taxa. Large differences in vegetation cover were observed over the field season in the grassland community, and matching the phenological timing of surveys within and between studies is clearly important if RPP estimates from these sites are to be comparable. Pollen assemblages from closely co-located moss polsters collected on different visits are shown to be variable in all communities, to a greater degree than can be explained by the sampling error associated with pollen counting, and further study of moss polsters as pollen traps is recommended
Field-testing at high-altitude: Recommendations from Leeds Metropolitan University’s Himalayan 2011 research expedition team
\u3ci\u3eSurefoot LC v. Sure Foot Corp.\u3c/i\u3e: A New Standard for Tenth Circuit Declaratory Judgment Jurisdiction in Intellectual Property Disputes, or How Cardtoons Got the Boot
The Exploration of Nationalism in the Works of Livy and Jacques-Louis David
The concept of nationalism is one that occupies a prevalent position in many ancient and modern works. Manifestations of such “valuation of the nation-state above all else” in art is often a natural consequence of a patriotic artist’s work. Art provides on opportunity for the artist to express feelings, to educate their audience, and to further their own political agendas. Two such artists that took advantage of the widespread capabilities and audience of art are Titus Livius and Jacques-Louis David. These men recognized the ability of art to inspire passion and to reach the masses, and they used it to their own advantage. Though the two are from widely varying times and cultures, the artists are similar in that the creations of their works serves as a means of promoting their respective nationalistic ideals. In this paper, I plan to explore the inclusion and advancement of those nationalistic political agendas by the artists. This will include an overview of David’s paintings the Oath of the Horati]and the Intervention of the Sabine Women is related to the corresponding passages recorded by Livy and a look at their potentially relatable messages, goals, and the achievement of those goal
Seeing the wood for the trees:Recent advances in the reconstruction of woodland in archaeological landscapes using pollen data
Pollen sequences record the vegetation cover of past landscapes, but translating a pollen diagram into a landscape reconstruction is not straightforward. This paper reviews recent advances in the reconstruction of woodland cover from palynological data and shows how they have been used to address three archaeologically relevant problems: • The detection of woodland presence and extent in a largely open landscape • The reconstruction of the habitat context of a specific archaeological site • The detection of woodland management Pollen surface samples which can be directly related to contemporary vegetation cover are shown to be useful both in their own right and as the basis for calibration of models of pollen dispersal and deposition. These models can be used as a foundation for quantitative reconstruction of past landscapes, for example using the Multiple Scenario Approach, or as a tool for construction and testing of hypotheses and to inform selection of coring sites. We argue that surface sample studies and simulation approaches are improving the scientific basis of reconstruction of past landscapes, and that these approaches offer new opportunities for communication and collaboration between archaeologists and environmental specialists
Do local habitat conditions affect estimates of relative pollen productivity and source area in heathlands?
Relative Pollen Productivity is an essential parameter for quantitative reconstruction of past land cover from pollen records, but published studies have produced a range of different values for the same taxa. Heathland habitats have limited plant diversity and strong spatial patterning, therefore are useful case studies to investigate aspects of pollen dispersal and deposition, but the estimated spatial area “sensed” by pollen records in these habitats also varies widely between studies. In this study, we estimate pollen productivity from two different microhabitats in a heathland ecosystem in order to investigate the role of local environmental conditions in any observed differences.Vegetation survey was carried out using the Crackles Bequest Project method, pollen assemblages from moss samples counted using standard methods, and relative pollen productivity and estimated source area derived using Extended R-Value analysis. Analysis of the data suggests that at least two pollen source areas exist at the sites studied, reflecting scales of landscape organisation. Microhabitat does not appear to have a marked effect on estimates of Relative Pollen Productivity in this heathland system. This study confirms earlier findings that the estimates obtained for some taxafrom heathlands are substantially different than those from gricultural landscapes,especially Poaceae. The findings suggest that the factors controlling Relative Pollen Productivity are still not fully understood, and that differences between locations may reflect real, habitat-led differences. Further investigation of this parameter, whichis central to reconstruction of past land cover from pollen records whether overtly incorporated via an algebraic model or less explicitly present via ecological narrative, biomisation or modern analog approaches, is clearly necessary
Cell patterning on photolithographically defined parylene-C:SiO2 substrates
Cell patterning platforms support broad research goals, such as construction of predefined in vitro neuronal networks and the exploration of certain central aspects of cellular physiology. To easily combine cell patterning with Multi-Electrode Arrays (MEAs) and silicon-based ‘lab on a chip’ technologies, a microfabrication-compatible protocol is required. We describe a method that utilizes deposition of the polymer parylene-C on SiO(2 )wafers. Photolithography enables accurate and reliable patterning of parylene-C at micron-level resolution. Subsequent activation by immersion in fetal bovine serum (or another specific activation solution) results in a substrate in which cultured cells adhere to, or are repulsed by, parylene or SiO(2) regions respectively. This technique has allowed patterning of a broad range of cell types (including primary murine hippocampal cells, HEK 293 cell line, human neuron-like teratocarcinoma cell line, primary murine cerebellar granule cells, and primary human glioma-derived stem-like cells). Interestingly, however, the platform is not universal; reflecting the importance of cell-specific adhesion molecules. This cell patterning process is cost effective, reliable, and importantly can be incorporated into standard microfabrication (chip manufacturing) protocols, paving the way for integration of microelectronic technology
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A role for palaeoecology in anticipating future change in mountain regions?
Family-Owned Newspapers: Filling Niches in Local U.S. Communities
Citation: Powers, A., Sohn, A. B., Briggs-Bunting, J. (2016) Family-Owned Newspapers: Filling Niches in Local U.S. Communities. Journal of Media Business Studies. 2(11)Since small town newspapers are facing increased competition and technological changes that are threatening their survival, the purpose of this paper was to analyze the strategy-making activities of these organizations from an ecological perspective. Findings indicate that family-owned newspapers were finding stability in retaining their core print businesses while migrating content to the web. Too many variations from the norm appeared to weaken financial footholds and were often eventually abandoned. Such behaviors indicate a rationale for upholding a “tried-and-true” approach in newspapers. While profits may fluctuate, the uncertainty that occurred with variation seemed to play a role in increasing the threat of failure for these small, family-owned newspapers
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