Showing papers by "University of Nebraska–Lincoln published in 1979"

Sources and Concentrations of Nitrate‐Nitrogen in Ground Water of the Central Platte Region, Nebraskaa

Abstract: During 1976-1977 nitrate-nitrogen (NO3-N) concentrations exceeded 10 mg/1 in 183 of the 256 ground-water samples collected from parts of Buffalo, Hall, and Merrick counties in Nebraska. Comparison of the isotopic values with those of potential nitrate sources suggested that the primary source of contamination in most wells was fertilizer and that a small percentage of the wells contained significant concentrations of NO3-N derived from animal wastes. A combination of two or more sources of contamination was assumed for those samples for which the source could not be identified. Significant negative correlations between δ15N and NO3-N (-0.35 in Buffalo and Hall Counties) and between δ5N and depth to water (–0.55 in Merrick County) indicate that denitrification is the major factor in isotopic fractionation of nitrogen from the nitrate sour

Measuring protein quality.

Abstract: An alternative to the time-consuming and expensive PER assay for measuring food protein quality is needed by the food industry. Many biological and chemical-based assays for measuring protein quality have been described in the literature. Most of these are still too complicated, time-consuming, or too narrow in the range of foods they will test for daily quality control use. In the past five years, rapid methods have been developed that employ chemical assays for essential amino acid composition and availability or biological assays that measure protein digestibility and growth on food proteins. Most of these assays can be completed in five days or less and are applicable to a broad range of foods. These developments have brightened the prospects for the eventual development of a rapid assay that the food industry routinely can use to monitor protein quality. This paper has discussed two assays that were tested with a wide variety of foods and that take less than 72 hr to complete. The C-PER assay, uses data on the in vitro protein digestibility and EAA composition of a food protein to predict its protein quality in terms of PER. The C-PER technique is not limited by the protein, fat, additive or spice levels in the food to be tested, and is therefore applicable to a wide range of food ingredients and processed foods. The second assay is based on the growth of the protozoanTetrahymena thermophila WH14 on a proteolytic enzyme hydrolyzed food sample along with in vitro protein digestibility data to predict protein quality in terms of T-PER. Because theTetrahymena are more difficult to control on a day to day basis, the error of the T-PER estimate is greater than that for the C-PER estimate. Also, sinceTetrahymena growth is greatly affected by various food additives and spices, caution should be used when this assay is used to measure protein quality in foods where the composition is not definitely known. The T-PER assay is best suited for assaying protein quality in protein-containing food ingredients, such as meats, flours, protein concentrates and isolates, or on foods where the exact composition is known.

Geographic Data Processing

Abstract: This survey attempts to provide a umfied framework for the constituent elements-originating In numerous and diverse disciplines--of geographical data processing systems. External aspects of such systems, as perceived by potential users, are discussed with regard to extent, coordinate system and base map, range of applications, input /output mechanisms, computer configuration, command and interaction, documentation, and administration.The internal aspects, which would concern the system designer, are analyzed in terms of the type of spatial variables involved and of their interrelationship with respect to common operations This point of view is shown to lead to a workable classificatmn of two-dimensional geometric algorithms and data structures. To provide concrete examples, ten representative geographic data processing systems, ranging from automated cartography to interactive decision support, are described. In conclusmn, some comparisons are drawn between geographmal data processing systems and their conventional business-oriented counterparts.

Pentamethylcyclopentadienyl Organoactinides. Trivalent Uranium Organometallic Chemistry and the Unusual Structure of Bis(pentamethylcyclopentadienyl)uranium Monochloride

Abstract: Die Titelverbindung (II), in der U(III) durch Pentamethylcyclopentadienyl-Liganden komplexiert ist, ist eine ausgezeichnete Ausgangsverbindung fur weitere U(III)-Verbindungen.

Selection for ovulation rate in swine: correlated response in litter size and weight.

Abstract: Nine generations of direct selection for ovulation rate (OR) were evaluated to determine the magnitude of the correlated response in three litter size and two litter weight traits. A total of 387 Select line and 394 Control line litters were included in the ten generations of data. Realized heritabili ty of OR was .42 -+ .06 based on the regression of response (SelectControl) on weighted cumulative selection differential. Regressions of line means on generation number were significant for lit ter birth weight in both lines (-.31 +.12 kg, Select ;.41 -+ .06 kg, Control) and for lit ter weaning weight (-3.4 -+ .8 kg) in the Control line. None of the other regressions of line means on generation number was significantly different from zero. Regressions of line difference (Select-Control) on generation number were .06 -+ .07, .07 -+ .07, .10 _+ .07, .10 +.10 kg and 1.2 -+ .8 kg for total number farrowed (TNF), number farrowed alive (NFA), number weaned (NW), l i t ter birth weight (LBW), and litter weaning weight (LWW), respectively. However, none of these estimates of correlated response was significantly different from zero. Estimates of realized genetic correlation obtained were .07 (OR-TNF), .11 (OR-NFA),

Leadership Reexamined: A Behavioral Approach

Abstract: Leadership is examined from a behavioral perspective. Evidence is presented that shows that existing theory and research largely builds in normative preconceptions about leadership and provides no prediction and control of performance behavior. An alternative behavioral interpretation is offered. A behavioral model is presented that examines both the macro and micro contingencies affecting leader-subordinate behavior. An expanded functional analysis that includes both overt and covert contingencies is presented. Specific guidelines for a behavioral approach to the study and practice of leadership are provided.

The Theory of Neglecting Stator Transients

Abstract: For more than four decades it has been thought that neglecting the so-called "ph terms" in Park's equations is equivalent to neglecting the electric transients due to the stator windings of a synchronous machine. Over the years, trial and error results have indicated that a more accurate prediction of synchronous machine performance could be obtained if the Aw(p6) terms in the stator voltage equations were also neglected. This paper provides a theoretical explanation of this experimental observation. In particular, it is established theoretically that in order to neglect the "stator transients" both the p* and Aw terms must be set equal to zero. This is accomplished by proving that the equivalence of neglecting the pq terms in the synchronous reference frame is to neglect the p* and Aw terms in all other reference frames. R-L transmission systems, synchronous and induction machines are considered.

The ross ice shelf project.

Abstract: A hole was drilled through the Ross Ice Shelf 450 kilometers from the barrier Scientific sampling through this hole revealed a sparse population of crustaceans, fish, and microbial biomass The seabed consists of mid-Miocene glaciomarine mud Geothermal heat flow is average Oceanographic data indicate an active circulation and melting at the base of the ice

Photoionization of chalcogen and halogen atoms: Cross sections and angular distributions

Abstract: The authors present a survey of the photoionization cross sections and photoelectron angular distributions for the outer $p$ subshell of the chalcogen atoms O, S, Se, and Te and the halogen atoms F, Cl, Br, and I. Results are presented in the Hartree-Fock approximation as well as in the central-potential-model approximation. An extensive analysis and comparison of the results obtained is presented which finds that exchange-interaction effects are strongest for the $n=3$ row elements.

Ice-thickness Patterns and the Dynamics of the Ross Ice Shelf, Antarctica *

Abstract: As part of the Ross Ice Shelf Geophysical and Glaciological Survey, a detailed map of ice thickness has been produced from airborne radar measurements closely tied to the network of survey stations on the ice-shelf surface. The map, drawn with a 20 m contour interval, reveals a highly complex pattern of thickness variations reflecting presumably, at least in part, complex ice-shelf dynamics. Many features of the thickness variation pattern appear to be associated with zones of grounded ice, but not all. Features of interest include many ice thickness minima, with closures up to 120m; a narrow, greatly elongated ridge-trough system 450 km or more in length; a few ice thickness maxima; steep regional gradients of 10 m/km in freely floating ice; highly contorted contours suggesting a large-scale “turbulence”; and at least two remarkable step-like changes in ice thickness. The irregularity of many of these features suggests dynamic non-equilibrium, i.e. the existence of transients in the dynamic system, so that the ice shelf as a whole suggests a state of rather rapid change. Flow-bands constructed on the basis of the strengths of the echo from the ice-water interface clearly delineate the outflow from the main East Antarctic outlet glaciers in the grid eastern part of the shelf. A discontinuous flow band originating in a small mountain glacier (Robb Glacier) suggests a variable mesoclimate in the vicinity of the glacier within the last thousand years. Strong reflections near the ice front suggest bottom melting of saline ice previously frozen on to the underside of the ice. Several rifts or incipient rifts in the ice shelf characteristically show two lateral bands of strong reflections with a non-reflecting zone in between.

Laboratory-based surveillance of influenza virus in the united states during the winter of 1977–1978 i periods of prevalence of h1n1 and h3n2 influenza a strains, their relative rates of isolation in different age groups, and detection of antigenic variants

Abstract: Influenza A (H3N2) viruses were isolated from outbreaks and epidemics of disease during the period December 1977 to March 1978. For the last two months of this period, H1N1 strains of influenza A were also responsible for epidemics. In some regions (e.g., Hawaii) co-circulation of H1N1 AND H3N2 strains occurred, whereas in other regions (e.g., Wisconsin) isolation of H3N2 strains had almost ceased prior to isolation of H1N1 strains. Few influenza B isolates were reported. Analysis of the ages of patients from whom specimens were submitted for influenza virus isolation confirmed that, whereas H3N2 strains were isolated from persons of all ages, greater than 97 per cent of H1N1 isolates in six states analyzed were recovered from patients less than 26 years old, although specimens were tested from older persons who were ill during the period of prevalence of H1N1 influenza. The majority of H3N2 isolates tested by hemagglutinin-inhibition reaction were similar to A/Texas/1/77, and the majority of H1N1 isolates were similar to A/USSR/90/77. Antigenic analysis of isolates, however, identified a small number of variants of H3N2 and H1N1 strains.

The Nature of Bis(cyclopentadienyl)uranium Dichloride and Cyclopentadienyluranium Trichloride in Solution and in the Solid State

Abstract: The composition of the compound (C/sub 5/H/sub 5/)/sub 2/UCl/sub 2/, prepared from uranium tetrachloride and thallium cyclopentadienide in DME (1,2-dimethyoxyethane), has been investigated in the solid state by infrared spectroscopy and x-ray powder diffraction, and in solution by electronic and /sup 1/H NMR spectroscopy. All results indicate that (C/sub 5/H/sub 5/)/sub 2/UCl/sub 2/ is a mixture of the known compounds (C/sub 5/H/sub 5/)/sub 3/UCl and (C/sub 5/H/sub 5/)UCl/sub 3/(DME). The structure of this latter species is proposed to be mer pseudooctahedral on the basis of solution NMR studies (which also show it to be sterochemically dynamic) and by analogy to the related complex, (CH/sub 3/C/sub 5/H/sub 4/)UCL/sub 3/(THF)/sub 2/, the solid-state molecular structure of which has been determined using single-crystal x-ray diffraction techniques. This compound crystallizes in the monoclinic space group P2/sub 1//n with four molecules in a cell of dimensions a = 10.481 (2) A, b = 12.981 (2) A, c = 13.834 (2) A, and ..beta.. = 105.86 (1)/sup 0/. Least-squares refinement of the 181 variables led to a value for the conventional R index (on F) of 0.058 for 3698 independent reflections having 2 theta/sub MoK..cap alpha..-bar/ 3 sigma(I). The coordinationmore » geometry about the uranium ion is approximately mer octahedral with the eta/sup 5/-CH/sub 3/C/sub 5/H/sub 4/ and one coordinated THF occupying trans axial positions, and the other THF and three chlorine atoms occupying equatorial positions. The U--C (cyclopentadienyl), U--Cl, and U--O distances average 2.720 (14), 2.623 (3), and 2.450 (8) A, respectively. The principal distortion of the coordination geometry from octahedral is a 0.47-A displacement of the uranium atom out of the equatorial plane toward the cyclopentadienyl ring. It is found that the THF ligands of (C/sub 5/H/sub 5/)UCl/sub 3/(THF)/sub 2/ are readily displaced by nitrogenous bases such as 2,2'-bipyridyl and 1,10-phenanthroline. 6 figures, 6 tables.« less

Differentiated perceptions of exertion: part I. mode of integration of regional signals.

Abstract: The mode of sensory integration of differentiated perceptions of exertion from the legs and chest was determined during sub-maximal cycle ergometer exercise. 50 male subjects performed three separate cycle ergometer tests. Power output was held constant at 840 kpm/min., while pedalling rate was randomly set at 40, 60, or 80 rpm. The over-all rating of perceived exertion was significantly lower than the rating for the legs and higher than that for the chest at each pedalling rate. Local signals from the legs dominated the sensory process. Central signals were less pronounced. The mean of the ratings for the legs and chest was slightly but significantly higher than the over-all rating at each pedalling rate. Therefore, the integration process at the superordinate level of sensory processing appeared as a weighted average of the involved regional signals.

Presence of a major (storage?) protein in dormant spores of the fungus Botryodiplodia theobromae.

Abstract: Approximately 23% of the protein isolated from dormant spores of Botryodiplodia theobromae consisted of a single polypeptide; the polypeptide is probably degraded during germination. Images