Showing papers by "University of Nebraska–Lincoln published in 1978"
TL;DR: Alkylation of reduced proteins prior to electrophoresis eliminates the problems caused by reoxidation of sulfhydryl-containing proteins during SDS-polyacrylamide gel electrophoreis.
218 citations
201 citations
TL;DR: In this paper, the results indicate that pre-slaughter stress and struggle may affect the color and textural characteristics of turkey meat, and the pectoralis muscle was significantly higher in heat stressed and free struggle birds compared to cold stressed and anesthetized birds.
194 citations
TL;DR: In this paper, the authors identified a typical form of the exporting adoption process regarding two dimensions: the initiating force and the rationality of the export adoption process, and measured the organizational structural characteristics of 35 Nebraska exporting manufacturers.
Abstract: This research identifies a typical form of the exporting adoption process regarding two dimensions—the initiating force and the rationality of the export adoption process. It was hypothesized, first, for this study that, in the export innovation adoption situation, the adoption process would be initiated more often by internally perceived problems or needs rather than by the passively received information about the innovation: exporting. A second major hypothesis took the view that the export adoption process was more rational than nonrational. Third, using various instruments—including Hage and Aiken's index—we measured the organizational structural characteristics of 35 Nebraska exporting manufacturers. The innovation-oriented and nonrational export adoption processes proved to be the more common in this group.
179 citations
TL;DR: In this article, a corrupt act is categorized by its four components: the donor, the favor, the public official and the payoff, and propositions about perceived corrupt and non-corrupt elements can be formulated and tested.
Abstract: Lack of a clear definition of political corruption has limited its systematic study by analysts of American politics. This article offers a conceptual framework with which to view corruption. A corrupt act is categorized by its four components: the donor, the favor, the public official and the payoff. For each component, propositions about perceived corrupt and noncorrupt elements can be formulated and tested. The usefulness of this scheme in analyzing attitudes about corruption is demonstrated with data from state legislators. Finally, the article suggests some future research possibilities using this scheme to compare elites and public or other groupings in the political system.
140 citations
TL;DR: In this article, it was shown that SSNTD's (etchable plastics) are not 1-hit detectors, but are 2-or-more hit detectors, which can mimic the response of biological cells to radiations of different quality.
136 citations
TL;DR: Differences in RNA migration pattern were observed among human strains as well as between human and animal strains; the number of interspecies differences was greater than thenumber of intraspecies differences.
135 citations
TL;DR: Changes in seeds of soybeans which occur during accelerated aging showed subsequent loss of vigor, a decline in early respiratory activity, increased leakage of electrolytes, losses of as much as 10% dry weight from imbibing cotyledons, and a decrease in the swelling response of the imbibed system (seed plus H(2)O).
Abstract: Changes in seeds of soybeans (Glycine max [L.] Merr. var. Wayne) which occur during accelerated aging (41 C, 100% relative humidity) showed subsequent loss of vigor, a decline in early respiratory activity, increased leakage of electrolytes, losses of as much as 10% dry weight from imbibing cotyledons, and a decrease in the swelling response of the imbibing system (seed plus H2O). Each of these changes with aging is interpreted as resulting from deteriorative changes in membranes.
135 citations
TL;DR: The Pliocene-Pleistocene boundary has tentatively been dated about 2.5 � 0.1 x 106 years, and glacial deposits in the central United States older than about two-thirds of that boundary may span that boundary.
Abstract: Confusion due to the conceptual usage of classic North American Pleistocene stage terms indicates the need for a new or revised terminology. The Pliocene-Pleistocene boundary has tentatively been dated about 2.5 ± 0.1 x 106 years. Glacial deposits in the central United States older than about 2.2 x 106 years may span that boundary.
125 citations
TL;DR: This technique greatly increased the efficiency of the infrared CO(2) analyzer in the laboratory for use in plant respiration and photosynthetic studies.
Abstract: A method has been developed to measure concentrations of CO2 in gases rapidly. A gas sample is injected into a flowing carrier gas that passes through an infrared CO2 analyzer. A strip chart recorded peak response is obtained which is proportional to the CO2 concentration. A resolution of better than 2 microliters of CO2 per liter of gas was obtained. Seven to 10 seconds were required for sample analysis once the sample was obtained. Sorghum bicolor plant respiration was determined at different temperatures by measuring CO2 using this system and by using a conventional system. The correlation between techniques was 0.996, and about the same variation occurred within each method. This technique greatly increased the efficiency of the infrared CO2 analyzer in our laboratory for use in plant respiration and photosynthetic studies.
115 citations
TL;DR: Root segments and root-soil cores from fields and nurseries of winter wheat and sorghum were tested for N2 fixation by using the acetylene reduction assay and numerous N2-fixing bacterial isolates were obtained from wheat and Sorghum roots that exhibited high nitrogenase activity.
Abstract: Root segments and root-soil cores (6.5-cm diameter) from fields and nurseries of winter wheat and sorghum were tested for N2 fixation by using the acetylene reduction assay. Wheat samples (approximately 1,200) from 109 sites generally had low or no activity (0 to 3.1 nmol of C2H4 produced per h per g [dry weight] of root segments), even after 24 h of incubation. However, a commercial field of Scout 66, located in western Nebraska, exhibited appreciable activity (290 nmol of C2H4 produced per h per g [dry weight] of root segments). Of 400 sorghum lines and crosses, grain sorghums (i.e., CK-60A, Wheatland A, B517, and NP-16) generally exhibited higher nitrogenase activity than forage sorghums or winter wheats. CK-60A, a male sterile grain sorghum, was sampled at four locations and had the most consistent activity of 24 to 1,100 nmol of C2H4 produced per h per core. The maximum rate extrapolated to 2.5 g of N per hectare per day. Numerous N2-fixing bacterial isolates were obtained from wheat and sorghum roots that exhibited high nitrogenase activity. Most isolates were members of the Enterobacteriacae, i.e., Klebsiella pneumoniae, Enterobacter cloacae, and Erwinia herbicola.
TL;DR: The data are taken to indicate that low temperature interferes with normal membrane reorganization during imbibition, probably by modifying the physical state of membrane phospholipids, and that the consequent abnormal organization of membranes is a basic cause of low temperature injury.
Abstract: Embryos, excised from seed coats of soybeans (Glycine max Merr. cv. ;Wayne'), leak profusely during the first minutes of imbibition. A discontinuity of temperature/leakage patterns occurs between 10 and 15 C; as embryos imbibe at 10 C or lower, disproportionately more solutes leak out per unit of water imbibed. Short periods of imbibition at or below 12 to 14 C reduce embryo germination and axis elongation; injury results from imbibition at 2 C for as little as 5 minutes. Humidifying embryos to 35 to 50% moisture before imbibition reduced leakage during imbibition and imparted some resistance to imbibitional chilling injury.The period of profuse leakage is interpreted as a time of membrane reorganization. Imposing a low temperature during this period prolongs the rapid leakage, suggesting delayed or faulty membrane reorganization. Reduced cold sensitivity of embryos with an initial 35 to 50% moisture content is presumed to be due to at least partial membrane reorganization in the embryo before imbibition. These data collectively are taken to indicate that low temperature interferes with normal membrane reorganization during imbibition, probably by modifying the physical state of membrane phospholipids, and that the consequent abnormal organization of membranes is a basic cause of low temperature injury.
TL;DR: The purpose of this chapter is to suggest the guidelines for phage characterization and nomenclature, and to set forth the minimum requirements for their description.
Abstract: Publisher Summary Bacteriophages or phages occur in a wide range of prokaryotes, including bacteria and blue-green algae. With an estimated 1650 isolates studied by electron microscopy, they are the largest viral group described. This group is expanding at a rate of about 130 to 150 virus descriptions per year. These large numbers reflect the relative ease, with which the phages are isolated and their enormous importance for molecular biology, genetics, and epidemiology. For example, a recent review lists typing sets for about 70 bacterial species and serotypes. Although most work has been done on the phages of bacteria pathogenic to humans, there is presently a trend toward studying the phages of nonmedical and sometimes arcane bacteria. The isolation of the new phages raises problems for the investigators, the journal editors, and the scientific public alike. At present, there is no agreement on parameters, methods, and nomenclature. This has led to widely different, often unsatisfactory, phage descriptions and many identical names for different phages. In addition, much effort seems to be devoted to the study of obsolete parameters or properties that, for the lack of standard methods, cannot be compared with existing data. Such a situation is detrimental to comparative virology. The purpose of this chapter is to suggest the guidelines for phage characterization and nomenclature, and to set forth the minimum requirements for their description.
TL;DR: The results indicate that the conventional tests for alternate respiration in plant tissues can be confounded by lipoxygenase; they suggest that propyl gallate can be used to assess the possible participation of lip oxygengenase in the O(2) uptake by plant tissues.
Abstract: The initial burst of respiratory activity (Qo2) of imbibing soybean (Glycine max [L.] Merr. var. Wayne) seed tissue is cyanide-insensitive, and sensitive to salicylhydroxamate: presumptive evidence for the presence of alternate respiration. The initial O2 consumption is also highly sensitive to propyl gallate. Soybean lipoxygenase exhibits similar characteristics of insensitivity to cyanide and sensitivity to salicylhydroxamate and to propyl gallate. The initial burst of respiration is enhanced by the addition of linoleic acid, a lipoxygenase substrate. These results indicate that the conventional tests for alternate respiration in plant tissues can be confounded by lipoxygenase; they also suggest that propyl gallate can be used to assess the possible participation of lipoxygenase in the O2 uptake by plant tissues.
TL;DR: In this article, the facile activation of CO by bis(pentamethylcyclopentadienyl)thorium and uranium alkyls, the molecular structure of the Th((CH/sub 3/)/sub 5/C/sub 5)/sub 2/(H/sub 2/H/H 2 )/H 3 ) dicarbonylation product, and some structure sensitivity observations on the carbon monoxide incorporation process are reported.
Abstract: The facile activation of CO by bis(pentamethylcyclopentadienyl)thorium and uranium alkyls, the molecular structure of the Th((CH/sub 3/)/sub 5/C/sub 5/)/sub 2/(CH/sub 3/)/sub 2/ dicarbonylation product, and some structure-sensitivity observations on the carbon monoxide incorporation process are reported. The compounds M((CH/sub 3/)/sub 5/C/sub 5/)/sub 2/(OC(CH/sub 3/) = C(CH/sub 3/)O))/sub 2/, (M = thorium or uranium) were prepared by equilibrating a toluene solution of the appropriate metal alkyl at -80/sup 0/C with CO (less than 1 atm) for 1h, and then warming the solution to room temperature. Single crystals of the compound were found to be monoclinic (space group P2, ln); a = 11.819(2), b = 13.661(3), c = 15.658(2)A, ..beta.. = 107.08(1), and z = 2. The compound is composed of centrosymmetric dimers in which each Th(IV) ion adopts the pseudotetrahedral ''bent sandwich'' configuration. The oxygen atoms of bridging 2-butene-2,3-diolate ligands constitute the organic portion of the ten-atom, two-Th metallocycle. Bond lengths and angles for selected chemically distinct bonds are given. Monoclinic products resulted when the actinide substituent was replaced with trimethylsilylmethyl groups to yield M((CH/sub 3/)/sub 5/C/sub 5/)/sub 2/(CH/sub 2/Si(CH/sub 3/)/sub 3/)/sub 2/. Carbonylation of the monoalkyl M(CH/sub 3/)/sub 5/C/sub 5/)/sub 2/(Cl)CH/sub 2/Si(CH/sub 3/)/sub 3/ complexes led to trimethylsilyl migration. Amore » plausible scheme for the observed CO activation and product formation is presented.« less
TL;DR: Responses were especially concerned with diet as it relates to weight control; those with higher knowledge scores consistently followed food patterns for weight-control diets similar to those used in training and pre-event diets.
Abstract: Nutritional knowledge, attitudes, and food patterns of women athletes at the University of Nebraska at Lincoln were studied. Mean test scores for nutritional knowledge were higher for questions relating to "nutrition for the athlete" than to "general nutrition." Attitudes toward nutrition were generally favorable, with a positive correlation between nutritional knowledge and attitudes. Athletes who had received some form of nutrition education had higher nutritional knowledge and attitude scores than those who had not. Respondents were especially concerned with diet as it relates to weight control; those with higher knowledge scores consistently followed food patterns for weight-control diets similar to those used in training and pre-event diets.
TL;DR: A method is described for the large-scale purification of the Bacillus thuringiensis protein crystal by zonal gradient centrifugation using a Beckman J21-B centrifuge equipped with a JCF-Z rotor.
Abstract: A method is described for the large-scale purification of the Bacillus thuringiensis protein crystal by zonal gradient centrifugation. NaBr gradients are employed in a Beckman J21-B centrifuge equipped with a JCF-Z rotor.
TL;DR: In this paper, the local and regional components of sensible heat advection (Aloc and Areg, respectively) are identified and their magnitudes in a semi-arid to sub-humid zone are established.
Abstract: Detailed knowledge of the advection of sensible heat is necessary to understand the energy balance of the evaporating surface in many parts of the world. Sensible heat advection can result from regional and/or local sources. The local and regional components of sensible heat advection (Aloc and Areg, respectively) are identified and their magnitudes in a semi-arid to sub-humid zone are established in the work reported here. Measurements of dry- and wet-bulb air temperature, wind speed and net radiation were made above an irrigated alfalfa field with relatively dry surroundings upwind at Mead, NE. A modified Bowen ratio-energy balance method which incorporates horizontal gradients of air temperature and vapor pressure was used to compute evapotranspiration (ET) rates. Sensible heat advection at the furthest upwind location in the irrigated field contributed from 15 to 50% of the energy consumed in ET on a daily basis. Areg was greatest on days with strong winds; Aloc was independent of wind speed....
TL;DR: No relationship appeared to exist due to the differences of progesterone or estrogen content in the various brands of oral contraceptives, and increased accumulative exposure to oral contraceptives apparently had no effect upon Oral Debris Indices or Gingival Inflammatory Indices.
Abstract: The relationship between gingival inflammation and type of oral contraceptive used or duration of use was investigated in 168 women between the age of 18-35. To qualify for the study patients had to have professional prophylaxis within the past year but not within the past month. An Oral Debris Index and Gingival Inflammatory Index was obtained during a clinical examination of four line angles for each patient following which the patients provided a history of their oral contraceptive use other drug use and current systemic diseases or conditions they may have. The clinical data were analyzed according to 1) current use of oral contraceptives; 2) brand of oral contraceptives used; and 3) duration of use. It was found that oral contraceptive users as a group (93 patients) had a significantly higher Gingival Inflammatory Index and a significantly lower Oral Debris Index. When this group was divided according to brand use users of Norinyl 1/50 and Ovral had a significantly lower Oral Debris Index than nonusers and users of Ovulen Ovral and Norinyl 1/80 had significantly higher Gingival Inflammatory Index. No differences were found based on different hormonal composition however or on duration of use. The higher gingival inflammatory indices in oral contraceptive users are in agreement with previous findings and may be due to elevated levels of progesterone. The lower Oral Debris Index in users may be caused by variability in oral hygiene among subjects or by an increased production of gingival fluid which may affect the disclosing solution. Further research is needed to determine the effect of long-term oral contraceptive use on various periodontal diseases.
TL;DR: The inter- and intralamellar types of Henneguya exilis Kudo (Myxosporida) infections from channel catfish are similar in spore structure and sporogenesis, but differ in the structure of their plasmodium wall and surface coat and in their relationship with the host cells.
Abstract: SYNOPSIS. The inter- and intralamellar types of Henneguya exilis Kudo (Myxosporida) infections from channel catfish are similar in spore structure and sporogenesis, but differ in the structure of their plasmodium wall and surface coat and in their relationship with the host cells. The 2 clinical types differ also in the sites of development and growth patterns of plasmodia within a gill filament. Interlamellar plasmodia are limited by 2 outer unit membranes which give rise to both single-and double-membraned pinocytic canals. Intralamellar plasmodia are limited by a single outer unit membrane which gives rise to single-membraned pinocytic canals. Interlamellar plasmodia are covered by a fine granular coat of highly variable thicknesses; in some regions there is direct contact between the parasite and cells of the host. There is some evidence that host cell cytoplasm as well as interstitial material are taken in by interlamellar plasmodia. In contrast, intralamellar plasmodia are covered by a fine granular coat of almost uniform thickness, which prevents direct contact between the parasite and cells of the host; probably only interstitial material is taken by these plasmodia.
TL;DR: It was found that use of jargon and data were related to Ratings of difficulty and technicality, but not to ratings of the evaluator or to agreement with theevaluator.
Abstract: Communication theory suggests that the effectiveness of a communication is related to who says what, how, and to whom. This study, using a communication theory paradigm, examined the impact of diff...
TL;DR: In this paper, the results of equilibrium studies involving CO 2 (g) (solubility and e.m.f. studies) were reviewed and assembled, together with entropies for related solids.
TL;DR: In the absence of potamotrygonid fossils, the atrophied rectal gland is strong evidence of marine ancestry for the freshwater rays, indicative of a long history of freshwater adaptation.
Abstract: 1. Contrary to some reports, a rectal gland is present in strictly freshwater stingrays of South American rivers (Potamotrygon spp.).2. The gland has the location and histological features of the salt-secreting rectal gland of marine elasmobranchs, but is much reduced in size and number of tubules.3. Its residual function, if any, is unknown.4. The rectal gland is associated with prominent myeloid lobes, here designated as rectomyeloid bodies.5. In the absence of potamotrygonid fossils, the atrophied rectal gland is strong evidence of marine ancestry for the freshwater rays.6. Both the reduced gland and the loss of urea retention in potamotrygonids are indicative of a long history of freshwater adaptation.
TL;DR: Quantitative determinations of numbers of bacteria in broth cultures demonstrated that sufficient quantities of antibiotics were released to be bactericidal to microorganisms within 45 min to 20 hr, dependent on the type of antibiotic, type of bacteria, concentration of antibiotic in the cement, and time of contact.
Abstract: In vivo experiments were performed to study elution rates of antibiotics combined with Surgical implex bone cement and efficacy in controlling bacterial infections. Cylinders of bone cement were implanted in animals and at the same time the surgical areas were infected with large numbers of bacteria. Gentamicin and Keflin were eluted from the cylinders in sufficient quantities to completely eliminate or markedly reduce the number of bacteria recovered from infected areas. Animals were also treated with an anti-inflammatory drug, hydrocortisone, prior to implantation of cylinders and infection. The antibiotics in the bone cement effectively destroyed the bacteria in these animals with impaired inflammatory responses as compared with control animals.
TL;DR: In this article, self-report measures of menstrual symptomatology, using the 8-factor Moos (1968, 1969 a,c) Menstrual Distress Questionnaire (MDQ), were investigated.
Abstract: Retrospective questionnaires show cyclical variations in moods and behaviors across the menstrual cycle. However, results obtained from daily mood questionnaires are inconsistent. In the present study, which ran for 11 weeks, self-report measures of menstrual symptomatology, using the 8-factor Moos (1968, 1969 a,c) Menstrual Distress Questionnaire (MDQ), were investigated. The MDQ was administered under conditions that made the menstrual cycle a salient (retrospective questionnaire) or not a salient (daily questionnaire) part of the study. The study included women who were taking and not taking oral contraceptives. A 2×3 analysis of variance (with the two groups of women and three menstrual cycle phases as independent variables) yielded broad cyclical variations only in the menstrual cycle salient condition. When the menstrual cycle was not a salient part of the study, only the pain factor reached significant cyclical variation (p<.01). A 2×3 analysis of variance (with the two types of questionnaires and three menstrual cycle phases as independent variables) indicated that for women not taking oral contraceptives the two questionnaires differed on pain (p<.01), concentration (p<.01), autonomic reaction (p<.05), and water retention (p<.01). Phase effects were significant on all factors, with largest cyclical variations in the menstrual cycle salient condition. A similar analysis for women taking oral contraceptives yielded fewer significant differences. These results suggest that questionnaires that make the menstrual cycle a salient part of the study may exaggerate possible cyclical variations in moods and behaviors.
TL;DR: The results demonstrate that specific prolactin receptors can be measured on collagenase dissociated mammary epithelial cells and this method permits a direct assessment of the number of receptors on a per cell basis rather than indirect estimates, based on average DNA or protein content of the tissue, composed of heterogeneous cell types.
TL;DR: In this article, normal incidence reflection spectra and Kramers-Kronig transforms are reported for a polydiacetylene crystal, DCHD (substituent group: N-carbazolymethyl).