Fecal Coliform Release Studies and Development of a Preliminary Nonpoint Source Transport Model for Indicator Bacteria

The effect of grazing on water quality has been documented by bacteriological studies of streams adjacent to grazed areas. Bacterial release from fecal deposits is a parameter of the pollution transport mechanism that is poorly understood. The objective of this study was to determine a fecal coliform release function for cattle fecal deposits. Standard cowpies were rained on with a rainfall simulator, and the fecal coliform counts were determined using the most probably number (MPN) method of enumeration. The fecal deposits were rained on at ages 2 through 100 days. The effects of rainfall intensity and recurrent rainfall were tested. Naturally occurring fecal deposits were also tested to compare their results with the results from the standard cowpies. A log-log regression was found to describe the decline in peak fecal coliform release with fecal deposit age. The 100-day-old fecal deposits produced peak counts of 4,200 fecal coliforms per 100 milliliters of water. This quantity of release is insignificant compared to the release from fresher fecal material. Rainfall intensity had little effect on peak fecal coliform release from fecal deposits that ere 2 or 10 days old. At age 20 days the effect of rainfall intensity was significant; the highest intensity gave the lowest peak counts, and the lowest intensity gave the highest peak counts. The effect of rainfall intensity appears to be related to the dryness of the fecal deposits. Peak fecal coliform counts were significantly lowered by raining on the fecal deposits more than once. This decline was thought to be produced by the loss of bacteria from the fecal deposits during the previous wettings. Standard cowpies produced a peak release regression that was not significantly different from the regression for the natural fecal deposits. Apparently, grossly manipulating the fecal deposits did not significantly change the release patterns

Psychometric comparison of three behavioural scales for the assessment of pain in critically ill patients unable to self-report

International audienc

Phylogenetic Hypotheses for the Monocotyledons Constructed from rbcL Sequence Data

DNA sequences for the plastid locus that encodes the large subunit of ribulose 1,5-bisphosphate carboxylase/oxygenase (rbcL) were determined for 18 species of monocotyledons in 15 families. These data were analyzed together with sequences for 60 other monocot species in a total of 52 families by the maximum likelihood method producing one, presumably optimal, topology. An additional 26 species were added (104 total monocot species) and analyzed by the parsimony method with an outgroup of 18 dicot species producing 109 trees of 3,932 steps. The rbcL data show at least moderate support for seven lineages corresponding to the following orders, superorders, or combinations: Arecanae; Asparagales (excluding Hypoxidaceae) plus Iridaceae; Cyclanthanae plus Pandananae; Dioscoreales; Orchidales; Typhales; and Zingiberanae. Six clades corresponding to families or genera are well supported, including: Agavaceae, Asphodelaceae, Bromeliaceae, Hypoxidaceae, Poaceae, and Tradescantia. The two, earliest diverging multispecies clades in our rbcL phylogenies, Alismatanae and Aranae, are only weakly supported, and Bromelianae, Commelinanae, and Lilianae are paraphyletic. In all analyses Acorus calamus is phylogenetically isolated as the sister species to the remaining species of monocotyledons

Phylogenetics of Seed Plants: An Analysis of Nucleotide Sequences from the Plastid Gene rbcL

We present the results of two exploratory parsimony analyses of DNA sequences from 475 and 499 species of seed plants, respectively, representing all major taxonomic groups. The data are exclusively from the chloroplast gene rbcL, which codes for the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO or RuBPCase). We used two different state-transformation assumptions resulting in two sets of cladograms: (i) equal-weighting for the 499-taxon analysis; and (ii) a procedure that differentially weights transversions over transitions within characters and codon positions among characters for the 475-taxon analysis. The degree of congruence between these results and other molecular, as well as morphological, cladistic studies indicates that rbcL sequence variation contains historical evidence appropriate for phylogenetic analysis at this taxonomic level of sampling. Because the topologies presented are necessarily approximate and cannot be evaluated adequately for internal support, these results should be assessed from the perspective of their predictive value and used to direct future studies, both molecular and morphological. In both analyses, the three genera of Gnetales are placed together as the sister group of the flowering plants, and the anomalous aquatic Ceratophyllum (Ceratophyllaceae) is sister to all other flowering plants. Several major lineages identified correspond well with at least some recent taxonomic schemes for angiosperms, particularly those of Dahlgren and Thorne. The basalmost clades within the angiosperms are orders of the apparently polyphyletic subclass Magnoliidae sensu Cronquist. The most conspicuous feature of the topology is that the major division is not monocot versus dicot, but rather one correlated with general pollen type: uniaperturate versus triaperturate. The Dilleniidae and Hamamelidae are the only subclasses that are grossly polyphyletic; an examination of the latter is presented as an example of the use of these broad analyses to focus more restricted studies. A broadly circumscribed Rosidae is paraphyletic to Asteridae and Dilleniidae. Subclass Caryophyllidae is monophyletic and derived from within Rosidae in the 475-taxon analysis but is sister to a group composed of broadly delineated Asteridae and Rosidae in the 499-taxon study

Manufacturing and morphing behavior of high-amplitude corrugated laminates

This talk considers thin-walled corrugated laminates where the corrugation shape consists of circular sections.At amplitudes higher than corresponding with semi-circles, shape undercuts appear which circumstance renders mold-less manufacturing, relying on thermal curvature of unsymmetric laminates more viable than other manufacturing methods. The deformations occurring after releasing the cured laminates from the flat lamination surface, as well as the morphing behavior, imply large deformations which we address with an analytic nonlinear morphing model. All modeling relies on periodicity of the corrugation pattern and large extension along the direction transverse to the corrugations. Periodicity defines the geometric unit cell and symmetries of geometry and internal loads within it enable a smaller mechanical unit cell. The nonlinear deformations are found by integration of curvature and strain that depend on internal loads, and these in turn on equilibrium with external morphing force. For the problem of removing discrepancy between internal forces relating to material strains and those holding equilibrium to external force, the Newton minimization method is employed because first and second derivatives of the chosen objective function are described analytically. The verified model is used to simulate morphing deformation and to study influence of laminate thickness and corrugation amplitude on line-force-stretch diagrams

A planar finite element formulation for corrugated laminates under transverse shear loading

ISSN:0263-8223ISSN:1879-108

Manufacturing method for high-amplitude corrugated thin-walled laminates

Manufacturing of corrugated carbon-fiber reinforced composite laminates based on circular segments poses a challenge if high corrugation amplitudes create undercuts. This paper suggests to leave the formation of such high-amplitude corrugation shapes to thermal deformation of flat lay-ups which is effected by the difference between curing and service temperatures. It is shown by simulations that the method works best for carbon fibers of moderate stiffness and toughened epoxy-resin systems with high curing temperatures. Simple methods for predicting resulting shapes and stress distributions are explained and they verify non-linear structural simulations with FEM. A manufactured demonstrator validates the results. In addition to pointing out the new manufacturing method, some attention is paid to the potential application of corrugated laminates as flexible skins in morphing wings. It is pointed out how easily the morphing sections can be integrated into the manufacturing of wing skin and numerical stress analyses underline the strength feasibility of the manufacturing method. It comes as an additional benefit of the suggested manufacturing method that sliding overlaps can be integrated to create an aerodynamically smooth surface.ISSN:0263-8223ISSN:1879-108

Exact model for the response of moderately thick laminates to transverse forces

Under the premise of homogeneous force, or curvature-gradient, distribution, a solution for transverse-shear strainsand stresses, warping functions, and through-thickness displacements is derived by satisfying all relations and con-ditions of linear elasticity. Only for calculating the substitute-plate transverse-stiffness matrix the principle of theminimum of the total potential energy is used as a scheme for correctly combining energetically conjugate compo-nents of stresses and strains for the entries of the substitute-plate transverse stiffness matrix. The model is valid for alllaminate and sandwich designs. The said premise renders the model a point theory rather than a structural theory, sothat it is a complement to the classical theory of laminated plates in the sense of mapping substitute-plate propertiesand distribution of state variables through the laminate thickness. This paper explains the modeling ideas and deriva-tions in detail. Predictions of the responses for a set of sample laminates of varying complexity, and comparison ofstiffness values with those obtained by a dedicated FEM formulation, verify the model.ISSN:0263-8223ISSN:1879-108

Response of moderately thick arbitrary laminates to transverse forces

Under the premise of homogeneous force, or curvature-gradient, distribution, a solution for transverse-shear strains and stresses, warping functions and through-thickness is derived by satisfying all relations and conditions of linear elasticity. Only for calculating the substitute-plate transverse-stiffness matrix the principle of the minimum of the total potential energy is used as a scheme for correctly combining energetically conjugate components of stresses and strains for the entries of the substitute-plate transverse stiffness matrix. The model is valid for all laminate and sandwich designs. The said premise renders the model a point theory rather than a structural theory, so that it is a complement to the classical theory of laminated plates in the sense of mapping substitute-plate properties and distribution of state variables through the laminate thickness. This paper explains the modeling ideas and derivations in detail. Predictions of the responses for a set of sample laminates of varying complexity, and comparison of stiffness values with those obtained by a dedicated FEM formulation, verify the model