A Survey of Lentic Waters with Respect to Dissolved and Particulate Lead

Some of the strongest temperature inversions in the world occur at Fairbanks, Alaska. Benson (1970) has reported that a temperature gradient of 10 to 30C/1OO m is common in the winter inversions that form at Fairbanks. Air pollution is especially severe during these inversions when it is accompanied by the formation of ice crystals in the air, a condition known as ice fog. This phenomenon occurs when the temperature drops below -20F (-35C) (Benson, 1970), and it intensifies with time if the inversion is not broken. The ice crystals in this fog have been found to adsorb dust and gasses, including the lead halides which are present in the air as a result of the combustion of tetraethyl lead and/or other lead-hydrocarbon compounds used as anti-knock additives in automotive gasoline. Lazrus et al. (1970) have found lead concentrations in precipitation to be highly significantly correlated with the amount of gasoline used in the area sampled. There are two factors that bring the concentration of lead to high levels in ice fogs. Evaporation of the ice crystals tends to concentrate pollutants in the air mass, especially over the core area of the city where precipitation is retarded by the heating effect of the city. Also, during the extreme cold weather accompanying this phenomenon, many people allow their cars to idle when they are parked to increase performance and for reasons of personal comfort. Eventually, much of the pollutants suspended in the ice fog is precipitated and causes unnaturally high levels of lead in the snow. (Winchester et al., 1967). It is suspected that some of this particulate lead collected in the snow may be carried along with the associated surface runoff into 1entic (standing) surface waters during thawing. The objectives of this project were: 1. to measure the amount of dissolved and particulate lead in a number of selected 1entic waters in the Fairbanks area, and 2. to measure the amount of lead that has been incorporated into net plankton organisms located in the selected lentic waters.The work upon which this report is based was supported by funds (Project A-035-ALAS) provided by the United States Department of the Interior, Office of Water Resources Research, as authorized under the Water Resources Act of 1964, as amended

Automated Netlist Generation for 3D Electrothermal and Electromagnetic Field Problems

We present a method for the automatic generation of netlists describing general three-dimensional electrothermal and electromagnetic field problems. Using a pair of structured orthogonal grids as spatial discretisation, a one-to-one correspondence between grid objects and circuit elements is obtained by employing the finite integration technique. The resulting circuit can then be solved with any standard available circuit simulator, alleviating the need for the implementation of a custom time integrator. Additionally, the approach straightforwardly allows for field-circuit coupling simulations by appropriately stamping the circuit description of lumped devices. As the computational domain in wave propagation problems must be finite, stamps representing absorbing boundary conditions are developed as well. Representative numerical examples are used to validate the approach. The results obtained by circuit simulation on the generated netlists are compared with appropriate reference solutions.Comment: This is a pre-print of an article published in the Journal of Computational Electronics. The final authenticated version is available online at: https://dx.doi.org/10.1007/s10825-019-01368-6. All numerical results can be reproduced by the Matlab code openly available at https://github.com/tc88/ANTHE

Evaluation of Urea and Dried Whey in Diets of Cows During Early Lactation

Previous research indicated that soluble nitrogen may be utilized more efficiently for rumen microbial production in diets containing dried whey. To further evaluate this, 33 Holstein, cows (30 multiparous and 3 primiparous) were fed one of three concentrate mixes containing all natural proteins (SBM). 1% urea (U), or 1% urea and 30% dried whey (UDW) from wk 3 through 16 postpartum. Urea replaced portions of the soybean meal in the SBM mix while dried whey replaced portions of the corn and soybean meal. Cows were fed total mixed rations consisting of 40% (dry matter basis) corn silage, 10% alfalfa hay, and 50% of respective concentrate mix. Diets were formulated to be isonitrogenous at 16% crude protein, but soluble nitrogen was formulated to be approximately 23, 30, and 42% of the total nitrogen for SBM, U, and UDW diets. Milk production and composition were adjusted by analysis of covariance using the second week milk production and composition as covariates. Milk yield was similar (33.8, 33.4, and 33.2 kg/day) for cows or cows fed SBM, U and UDW, respectively, indicating that diets high in soluble nitrogen can support milk production equal to that of natural protein supplemented rations. Production of 4% fat-corrected milk (29.9, 28.0 and 29.2 kg/day) was lower for cows fed U diet because of lower milk fat percentage (3.23, 2.94 and) was lower for cows fed U diet because of lower milk fat percentages (3.23, 2.94, and 3.23%). Milk protein percentages (3.10, 3.04, and 3.04%) and solids-not-fat percentages (8.74, 8.79, and 8.81%) were not affected by type of concentrate · fed. Milk solid percentages (12.02, 11.70, and 12.01%) and production of solids-corrected milk (30.3, 28.6, and 29.6 kg/day) were higher for cows fed SBM · and UDW versus U. Dry matter intakes · (22.0, 20.2, and 23.1 kg/day) were highest for cows fed UDW and lowest when fed U. Rumen parameters showed a decrease in molar percentages of acetate (56.6, 50.3, and 50.2%) for cows fed U, and UDW, but cows fed U had higher molar percentages of propionate (24.8, 28.6, and 25.0%). Molar percentages of butyrate were higher (13.6, 14.4, and 18.4%) for cows fed UDW. Ratios of acetate+butyrate: propionate were highest (2.95, 2.40, and 2.93) for cows fed SBM and UDW. Concentrations of rumen ammonia (11.8, 20.3 and 13.5 mg/dl) and serum urea (19.5, 22.9, and 16.5 mg/dl) were highest for cows fed U. In conclusion the utilization of urea nitrogen for milk production was improves by adding dried whey to simulate rumen microbial protein synthesis to diets of early lactation cow

A Multi-scale View of the Emergent Complexity of Life: A Free-energy Proposal

We review some of the main implications of the free-energy principle (FEP) for the study of the self-organization of living systems – and how the FEP can help us to understand (and model) biotic self-organization across the many temporal and spatial scales over which life exists. In order to maintain its integrity as a bounded system, any biological system - from single cells to complex organisms and societies - has to limit the disorder or dispersion (i.e., the long-run entropy) of its constituent states. We review how this can be achieved by living systems that minimize their variational free energy. Variational free energy is an information theoretic construct, originally introduced into theoretical neuroscience and biology to explain perception, action, and learning. It has since been extended to explain the evolution, development, form, and function of entire organisms, providing a principled model of biotic self-organization and autopoiesis. It has provided insights into biological systems across spatiotemporal scales, ranging from microscales (e.g., sub- and multicellular dynamics), to intermediate scales (e.g., groups of interacting animals and culture), through to macroscale phenomena (the evolution of entire species). A crucial corollary of the FEP is that an organism just is (i.e., embodies or entails) an implicit model of its environment. As such, organisms come to embody causal relationships of their ecological niche, which, in turn, is influenced by their resulting behaviors. Crucially, free-energy minimization can be shown to be equivalent to the maximization of Bayesian model evidence. This allows us to cast natural selection in terms of Bayesian model selection, providing a robust theoretical account of how organisms come to match or accommodate the spatiotemporal complexity of their surrounding niche. In line with the theme of this volume; namely, biological complexity and self-organization, this chapter will examine a variational approach to self-organization across multiple dynamical scales

Permeable Surface Corrections for Ffowcs Williams and Hawkings Integrals

The acoustic prediction methodology discussed herein applies an acoustic analogy to calculate the sound generated by sources in an aerodynamic simulation. Sound is propagated from the computed flow field by integrating the Ffowcs Williams and Hawkings equation on a suitable control surface. Previous research suggests that, for some applications, the integration surface must be placed away from the solid surface to incorporate source contributions from within the flow volume. As such, the fluid mechanisms in the input flow field that contribute to the far-field noise are accounted for by their mathematical projection as a distribution of source terms on a permeable surface. The passage of nonacoustic disturbances through such an integration surface can result in significant error in an acoustic calculation. A correction for the error is derived in the frequency domain using a frozen gust assumption. The correction is found to work reasonably well in several test cases where the error is a small fraction of the actual radiated noise. However, satisfactory agreement has not been obtained between noise predictions using the solution from a three-dimensional, detached-eddy simulation of flow over a cylinder

Teff: A New Annual Forage Grass for South Dakota?

Teff (Eragrostis tef Zucc. Trotter) is a major cereal crop in Ethiopia and has been grown in other African countries as a hay crop. Teff is a warm-season, annual grass that has rapid seed germination and seedling development. It also is well adapted to dry climates. These qualities indicate that teff could be used in this region of the U.S. as a supplemental forage during periods when other forage supplies are diminished. In South Dakota, late summer is when forage supplies are typically low. Teff has been marketed recently in South Dakota under the name “Dessie Summer Lovegrass.” This marketing campaign has created interest among producers in the crop’s forage potential. The following information summarizes research conducted at SDSU, over several years, on the forage potential of teff

Credit Rationing Effects of Credit Value-at-Risk

Banks provide risky loans to firms which have superior information regarding the quality of their projects. Due to asymmetric information the banks face the risk of adverse selection. Credit Value-at-Risk (CVaR) regulation counters the problem of low quality, i.e. high risk, loans and therefore reduces the risk of the bank loan portfolio. However, CVaR regulation distorts the operation of credit markets. We show that a binding CVaR constraint introduces credit rationing and lowers social welfare. CVaR regulation also affects the operation of monetary policy

(5R,6S)-4-Isopropyl-5-methyl-6-phenyl-3-propanoyl-2H-1,3,4-oxadiazinan-2-one

The title compound, C16H22N2O3, was synthesized during the course of a study on (1R,2S)-norephedrine-derived 1,3,4-oxadiazinan-2-ones. The conformation adopted by the isopropyl group is pseudo-axial relative to the oxadiazinan core. The allylic strain contributes to this conformational arrangement

THE RELATIONSHIP BETWEEN COLLECTIVE STUDENT TRUST AND STUDENT ACHIEVEMENT

The relationship between collective student trust and student achievement was tested in a sample of 1,748 5th grade students in 34 Title I elementary schools in an urban and urban fringe district. Trust was defined, the conditions of trust described, and the facets of trust discussed. Collective trust was distinguished from relational trust and evidence on the effects of other trust was reviewed. Multi-level modeling was utilized to analyze nested data. Results indicate that collective student trust was associated with higher mathematics and reading achievement in schools. When controlling for SES, school size, and school identification, collective student trust had the largest unique effect on mathematics and reading achievement. Collective student trust was the only significant school level factor for achievement differences. A post hoc analysis indicated that high poverty schools with high collective student trust had higher achievement than high poverty schools with low trust. Results are discussed through the lens of self-determination theory