Showing papers by "University of Georgia published in 1982"
TL;DR: In this paper, a summary and review of 94 catchment experiments shows that accumulated information on the effect of vegetation changes on water yield can be used for practical purposes, since no experiments, with the exception of perhaps one, have resulted in reductions in water yield with reductions in cover, or increases in yield, with increases in cover.
2,455 citations
TL;DR: In this paper, the significance of historical events changes from one generation to the next according to a changing infrastructure of societal problems and needs, and the bearing of these findings on different theories of collective memory is discussed.
Abstract: Using as data the events and persons commemorated in the United States Capitol, this inquiry demonstrates how the significance of historical events changes from one generation to the next according to a changing infrastructure of societal problems and needs. Before the Civil War, two historical periods, colonization and revolution, produced the only events and heroes on whose commemoration a deeply divided Congress could agree. Once the unity of the nation was brought about by force of arms, the pattern of commemoration changed. Belated recognition was given to the events and heroes of the postrevolutionary period and to outstanding regional, as opposed to national, figures. The commemoration of office incumbency was superimposed on that of extraordinary military and political achievement, thus celebrating the stable institutional structures into which the charisma of the nation's founders finally became routinized. These and other changes in the Capitol's commemorative symbolism reflect the Civil War's solution to the antebellum problems of integration and pattern maintenance. The bearing of these findings on different theories of collective memory is discussed.
497 citations
01 Jan 1982
TL;DR: For studies in systematic and evolutionary biology, many kinds of molecular data have the unusual distinction of providing “common yardsticks” for quantitatively comparing genetic distances in phylogenetically distinct arrays of species.
Abstract: For studies in systematic and evolutionary biology, many kinds of molecular data have the unusual distinction of providing “common yardsticks” for quantitatively comparing genetic distances in phylogenetically distinct arrays of species. Yet after more than two decades of study, the genetic information residing in DNAs and proteins has only barely been tapped and employed in a comparative framework. Some tantalizing preliminary conclusions have emerged. For example, when different kinds of organisms, such as frogs and mammals, are contrasted, it appears that rates of evolution in structural genes (those that encode proteins) can proceed independently of rates of evolution in organismal morphology and way of life (Cherry et al., 1978; King and Wilson, 1975).
352 citations
TL;DR: In this paper, two inexperienced sensory panelists rated a series of ground beef samples four or six times for intensity of oxidized flavor and found that the initial range of oxidised flavor detection for this panel group was within a range of TBA numbers that closely resembled the previously determined threshold level for trained panelists.
Abstract: Fifty-two inexperienced sensory panelists rated a series of ground beef samples four or six times for intensity of oxidized flavor. Correlation coefficients for sensory scores versus TBA numbers were significant but low. Variability in panelist scoring appeared to account partly for the lower values. Of the 52 panelists tested, 28 were determined statistically to be consistent in their scoring of the treatment variables. Correlation coefficients were higher for this group of panelists. The initial range of oxidized flavor detection for this panel group was within a range of TBA numbers that closely resembled the previously determined threshold level for trained panelists.
327 citations
TL;DR: High levels of inbreeding, homozygosity, and patchiness in the spatial distribution of genotypes are expected in plant populations with breeding systems based on nearest-neighbor pollination, and such observations require no explanation by natural selection or other deterministic forces.
Abstract: The population genetic consequences of nearest-neighbor pollination in an outcrossing plant species were investigated through computer simulations. The genetic system consisted of two alleles at a single locus in a self-incompatible plant that mates by random pollen transfer from a neighboring individual. Beginning with a random distribution of genotypes, restricted pollen and seed dispersal were applied each generation to 10,000 individuals spaced uniformly on a square grid. This restricted gene flow caused inbreeding, a rapid increase in homozygosity, and striking microgeographic differentiation of the populations. Patches of homozygotes bordered by heterozygotes formed quickly and persisted for many generations. Thus, high levels of inbreeding, homozygosity, and patchiness in the spatial distribution of genotypes are expected in plant populations with breeding systems based on nearest-neighbor pollination, and such observations require no explanation by natural selection or other deterministic forces.
294 citations
TL;DR: Daphnia has no feeding threshold or reduced filtering activity at low concentrations such as are predicted by optimal foraging models, and does not orient to or alter swimming patterns in response to algal patches.
Abstract: Abstruct Swimming patterns, fecging behaviors, and ingestion, filtering, assimilation, and respiration rates were measured for Daphnia mugnu in food concentrations from 0 to 10” Chlamydomonas reinhnrdi cells * cm-“, equivalent to O-20 mg C* liter-‘. A Helling type 2 functional response curve or an Ivlev model without a threshold appear to be biologically meaningful descriptions of Daphnia feeding response to different food concentrations. Daphnia has no feeding threshold or reduced filtering activity at low concentrations such as are predicted by optimal foraging models. Above the incipient limiting concentration, constant ingestion rates and an over-collection of food result in increased rejection rates. These behaviors may cause high respiratory rates and reduced net assimilation rates at the highest food concentration. Daphnia does not orient to or alter swimming patterns in response to algal patches.
291 citations
TL;DR: These results indicate that macroinvertebrate consumers, primarily insects, are important in regulating rates of detritus processing and availability to downstream communities.
Abstract: Insecticide treatment of a small, Appalachian forest stream caused massive downstream insect drift and reduced aquatic insect densities to <10% of an adjacent untreated reference stream. Reduction in breakdown rates of leaf detritus was accompanied by differences in quantity and composition of benthic organic matter between the two streams. Following treatment, transport of particulate organic matter was significantly lower in the treated stream than in the reference stream whereas no significant differences existed prior to treatment. Our results indicate that macroinvertebrate consumers, primarily insects, are important in regulating rates of detritus processing and availability to downstream communities.
286 citations
TL;DR: Expressing ovarian weight as an exponential function of some measure of body size may provide a more appropriate gonadal index.
276 citations
TL;DR: The adaptive significance of different types of inflorescences in flowering plants has been largely ignored but the few published studies investigating adaptive aspects of floral displays suggest that numbers of flowers and their arrangement in space and time determine levels of pollination and fruit-set in natural populations.
Abstract: The adaptive significance of different types of inflorescences in flowering plants has been largely ignored. The few published studies investigating adaptive aspects of floral displays suggest that numbers of flowers and their arrangement in space and time determine levels of pollination and fruit-set in natural populations. The frequently conflicting demands placed on inflorescence architecture have led to an evolutionary compromise that maximizes the genetic contribution of an individual plant to the next generation. These conflicting demands include pollinator attraction vs. ovary competition, fruit dispersal vs. fruit predation, and reproductive vs. vegetative resource allocation. In most cases, the inflorescence size most successful in fruit production is also the most frequent in natural populations. In addition to quantity of offspring, inflorescence architecture affects, and in turn is affected by, the quality of offspring that result from selfing vs. outcrossing.
273 citations
TL;DR: The Topographic Relative Moisture Index (TRMI) as mentioned in this paper is designed to indicate the relative soil moisture availability among sites in mountain terrain, which is a summed scalar index of four slope parameters: topographic position, slope aspect, steepness, and slope configuration.
Abstract: The Topographic Relative Moisture Index (TRMI), designed to indicate the relative soil moisture availability among sites in mountain terrain, is described. The TRMI is a summed scalar index of four slope parameters: topographic position, slope aspect, steepness, and slope configuration. A review of other methods of characterizing site moisture relations, including direct monitoring, water-balance climatology, site index, and other inferential topographic/edaphic indices, reveals that the simple, straightforward application of the TRMI is rapid, inexpensive, and effective in field research. The ability of the TRMI to portray significant patterns of plant response to environment is demonstrated from empirical studies at both the species-level (the ecology of Arizona cypress) and community-level (forest patterns in Yosemite National Park).
271 citations
TL;DR: It is proposed that differences in plant height and productivity of the salt-marsh cordgrass Spartina alterniflora are the result of a dynamic interaction among tidal water movement, dissolved iron and sulfide concentrations in marsh soils, and bacterial sulfate reduction.
Abstract: It is proposed that differences in plant height and productivity of the salt-marsh cordgrass Spartina alterniflora are the result of a dynamic interaction among tidal water movement, dissolved iron and sulfide concentrations in marsh soils, and bacterial sulfate reduction. Tidal water movement regulates the input of iron into marsh soils and the drainage of sulfide-containing interstitial water, and thereby controls the concentration of dissolved sulfide formed as a result of bacterial sulfate reduction. Near tidal creeks, where water movement and plant height and production are greatest, sulfide concentrations are lowest; in more elevated regions of marsh, where water movement andplant production are least, sulfide concentrations are highest. Plant height and productivity may be limited by the effects of sulfide on nutrient uptake.
TL;DR: This paper examined the effects of victim and offender intoxication on attributions of blame in a rape incident and found that the male offender was attributed less and the situation was attributed more responsibility when the offender was drunk than when he was sober.
Abstract: This study examined the effects of victim and offender intoxication on attributions of blame in a rape incident. Participants read scenarios of a rape incident in which victim, offender, both, or neither were intoxicated. The male offender was attributed less and the situation was attributed more responsibility when the offender was drunk than when he was sober. In addition, participants derogated the female victim's character and assigned her greater responsibility when she was drunk than when she was sober.
TL;DR: The results indicated that the most important variables affecting decision support system usage were accuracy ofoutput, user training, relevancy of output, and the decision maker's experience.
Abstract: This study investigates factors that may affect the use of decision support systems The independent variables investigated included: characteristics of the decision makers such as age, educational level, experience, and cognitive style; characteristics of the decision support system such as response time, accuracy, timeliness, relevancy of output, format, and the distance traveled to interact with the system; and characteristics of the implementation process such as user involvement, user training, and top management support The study included 8 systems and 64 subjects from the oil industry The results indicated that the most important variables affecting decision support system usage were accuracy of output, user training, relevancy of output, and the decision maker's experience
Subject Areas: Decision Support Systems, Information Management, and Organizational Behavior
TL;DR: In this article, the authors specify a model in which Congressmen, constituents, and campaign contributors simultaneously decide on behavior, and empirically test this model using roll call voting on eight bills dealing with economic regulation and find support for the model.
Abstract: In this paper we specify a model in which Congressmen, constituents, and campaign contributors simultaneously decide on behavior. Constituents and contributors desire to influence the voting behavior of Congressmen; Congressmen, on the other hand, want to be elected and vote accordingly. We empirically test this model using roll call voting on eight bills dealing with economic regulation and find support for the model. Our results indicate that part of the voting behavior of Congressmen may be explained by noneconomic factors. We also find that unions and businesses as campaign contributors are sometimes influential; unions are more often influential than is business. Ideological factors are also important in explaining voting.
TL;DR: In this paper, differences in first-year, fifth-year and former teachers on measures of efficacy, ego development, and problem solving were analyzed, with an alpha level of.05.
Abstract: Differences in first-year (N=50), fifth-year (N=49) and former (N=30) teachers on measures of efficacy, ego development, and problem solving were analyzed. The three groups were graduates from the same university who responded to a written survey. ANOVA was used for each variable across all groups, with an alpha level of.05, and the Scheffe multiple range test was used to determine significance between groups. On measures of efficacy and ego development, both first-year and fifth-year teachers scored significantly higher than former teachers, but did not differ from each other. There were no significant differences among the groups on the measure of problem solving.
TL;DR: In this article, a self-evaluation maintenance (SEM) model was used to make predictions about the positivity of perception of the performance of friends and strangers, and the model predicted that when the target of perception is close (i.e., a friend) the target's performance should be perceived more positively on dimensions of low personal relevance (to the perceiver) and less positively on dimension of high personal relevance.
Abstract: A self-evaluation maintenance (SEM) model was used to make predictions about the positivity of perception of the performance of friends and strangers. The model predicts that when the target of perception is close (i.e., a friend) the target's performance should be perceived more positively on dimensions of low personal relevance (to the perceiver) and less positively on dimensions of high personal relevance. If the target is psychologically distant (i.e., a stranger), this tendency should be attenuated. Thirty-four female subjects were given positive and negative feedback on a social sensitivity and an esthetic judgment task. One task had greater relevance for some subjects and the other task had greater relevance for the remaining subjects. Subjects rated their perception of a friend's and a stranger's performance on these tasks. The patterning of positivity in perception conformed to the pattern predicted by the SEM model. Subjects' awareness of their behavior as well as individual differences in self-esteem and repression-sensitization were also examined and discussed.
TL;DR: Remote sensor data with spatial resolutions corresponding to 0-5-10m IFOV are required to define adequately the high frequency detail which characterizes the urban scene.
Abstract: Remote sensor data with spatial resolutions corresponding to 0-5-10m IFOV are required to define adequately the high frequency detail which characterizes the urban scene. Effective analyses of the small parcels, compact structures and narrow street patterns typical of Asian environments will necessitate data of much higher resolution than are required for Western countries. Consequently it is unlikely that satellite image data expected for the 1980s will replace aerial photographs as a primary source of information about urban areas.
TL;DR: Prior knowledge was varied in problem solving, thinking, and reading tasks in three experiments as discussed by the authors, and the results of all three experiments were consistent with the hypothesis that prior knowledge uses capacity in the active processing system.
TL;DR: This paper aims to demonstrate the efforts towards in-situ applicability of EMMARM, as to provide real-time information about the response of the immune system to antibiotics.
Abstract: 1 Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois 60115 z Houghton Poultry Research Station, Huntingdon, Cambs PE17 2DA, United Kingdom 3 The Wistar Institute, Thirty-Sixth Street at Spruce, Philadelphia, Pennsylvania 19104 4 Department of Microbiology, New York University School of Medicine, 550 First Avenue, New York, New York 10016 5 College de France, Laboratoire de M6dicine Exp6rimentale, 11, Place Marcelin-Berthelot, 75231 Paris, Cedex 05, France 6 Institute for General and Experimental Pathology, University of Innsbruck, Fritz-Pregl-Strasse 3, A-6020 Innsbruck, Austria 7 Institute for Experimental Immunology, University of Copenhagen, N0rre Alle 71, DK-2100 Copenhagen 0, Denmark s Department of Immunology and MRC Group of Immunoregulation, University of Alberta, Edmonton, Alberta, Canada 9 Department of Animal Science, Iowa State University, Ames, Iowa 50011 10 Basel Institute for Immunology, Grenzacherstrasse 487, CH-4005 Basel, Switzerland ~1 Department of Avian Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30605 a Department of Medical Microbiology, Turku University, Turku, Finland 20520
TL;DR: In this article, the complete nucleotide sequence of a soybean actin gene carried on the recombinant plasmid pSAc3 was determined from the nucleotide sequences, which is composed of 376 amino acids.
Abstract: Soybean contains a small multigene family of actin-related sequences. We have determined the complete nucleotide sequence of a soybean actin gene carried on the recombinant plasmid pSAc3. As deduced from the nucleotide sequence, this soybean actin is composed of 376 amino acids. Compared to other eukaryotic actins, pSAc3 actin has a deletion of one amino acid between residues 118 and 122. The initiator methionine is followed by alanine, which is not found at this position in other eukaryotic actins. pSAc3 actin differs, in primary sequence, more from fungal and animal actins than any of the known nonplant actins differ from each other. pSAc3 actin appears to be related to both cytoplasmic and muscle specific actins in the location of specific NH2-terminal amino acids. The coding sequence is interrupted by three small introns, each less than 90 base pairs long. The splice junctions are similar to those found in other eukaryotic genes, suggesting the presence of a similar splicing apparatus in higher plants. Introns 1 and 3 interrupt the reading frame after codons 20 and 355, respectively. Intron 2 splits a glycine codon at position 151. None of these intron positions is conserved relative to the positions of introns in other actin genes examined.
TL;DR: In plants possessing a mixed selfing and random mating system, outcrossing rate t can be estimated from progeny genotype arrays but if there is heterogeneity of gene frequency between subpopulations, these estimates are severely biased downwards.
Abstract: In plants possessing a mixed selfing and random mating system, outcrossing rate t can be estimated from progeny genotype arrays. Computer simulation studies show that if there is heterogeneity of gene frequency between subpopulations, these estimates of t are severely biased downwards, the degree of bias increasing as the true value of t increases. This effect has been demonstrated in the field using experimental populations of Ipomoea purpurea. These field studies also provide evidence for pollen “carryover” in I. purpurea.
TL;DR: A study of ecosystem recovery following forest cutting, forest cutting and burning, and forest clearing by bulldozing was conducted in Amazon caatinga forest in the upper Rio Negro Region of southern Venezuela to evaluate vegetation composition, biomass, nutrient accumulation, soil characteristics, and nutrient leaching.
Abstract: A study of ecosystem recovery following forest cutting, forest cutting and burning, and forest clearing by bulldozing was conducted in Amazon caatinga forest in the upper Rio Negro Region of southern Venezuela. Ecosystem recovery was evaluated by measuring vegetation composition, biomass, nutrient accumulation, soil characteristics, and nutrient leaching. As disturbance increased in intensity, the early successional vegetation changed from primary forest trees (cut treatment) to successional woody species (cut and burned treatment) to forbs and grasses (bulldozed treatment). Soil nutrient levels were greater in both the cut and the cut and burned treatment plots than in the control forest three years after the disturbances presumably because of steady transfers of nutrients from the forest slash to the soil. Soil nutrient levels in the bulldozed plot were much lower than the control forest because of top soil removal. Aboveground biomass at three years was 1291 g m2 in the cut site, 870 g m2 in the cut and burned site, and 77 g m2 in the bulldozed site. Given these rates of biomass accumulation, approximately 100 yr will be required for both the cut and the cut and burned sites to reach biomass levels characteristic of mature caatinga forest, while more than 1000 yr will be necessary in the case of the bulldozed site.
TL;DR: In this article, microarthropods dominated the animal community on decaying wood with oribatid mites and collembolans the most numerous on 0-1 cm twigs and lowest on 3-5 cm branches.
Abstract: Unconfirmed Quercus prinus woody litter of three size classes (0-1, 1-3. and 3-5 cm diameter) was placed on forest floors of a control hardwood watershed and on mesic and xeric sites of a clear-cut watershed at Coweeta Hydrologic Laboratory, North Carolina. Exponential decay coefficients for mass loss on the control were ,1524, .1728, and .0912 yr~' for 0-1, 1-3, and 3-5 cm branches, respectively. Coefficients for 0-1, 1-3, and 3-5 cm branches were .1752, .0756, and .1644 yr"1 on the mesic site and .0456, .0948, and .0377 yr~' on the xeric site. The effect of site differences on decomposition rate was greater than the effect of diameter, although an inverse relationship be- tween diameter and decay coefficient is suggested. Time in the field, temperature, moisture, and microarthropod abundance also appeared to influence decomposition rate. Microarthropods dominated the animal community on decaying wood with oribatid mites and collembolans the most numerous. Microarthropod densities were highest on 0-1 cm twigs and lowest on 3-5 cm branches. Microarthropod densities were generally highest on the control, slightly de- pressed on the mesic site, and greatly depressed on the xeric site. Time in the field and state of decomposition both positively correlated with microarthropod abundance. Calcium concentration and total calcium exhibited transitory increases but little net change at the end of 1 yr in experimental branches. Total potassium decreased on all sites for 6 mo and for 12 mo on the control and xeric sites, with =60% remaining after 1 yr. Total potassium increased rapidly on the mesic site over the last 6 mo and reached 110% of the initial amount. Temperature, moisture, microbes, and microarthropods appeared to control nutrient dynamics. Woody litter dynamics were more important in terms of nutrient conservation on the clear-cut watershed than on the control and contributed to the resilience of the system. Removal or destruction of woody debris after clear-cutting would decrease the nutrient conservation properties of decaying wood and would probably contribute to watershed output of nutrients.
TL;DR: A study of plant succession during and following slash-and-burn agriculture near the town of San Carlos de Rio Negro in southern Venezuela found that forbs and grasses dominated immediately following farm site abandonment, but by one year these had begun to senesce and fast-growing successional woody species were common.
Abstract: In a study of plant succession during and following slash-and-burn agriculture near the town of San Carlos de Rio Negro in southern Venezuela we found that: 1. Weeds established just as readily in plots with Manihot esculenta (the principal crop plant of the region) present as in plots with M. esculen:a removed. 2. Repeated farm-plot weedings caused woody plants to decline in numbers and biomass and herbaceous plants to increase. 3. Forbs and grasses dominated immediately following farm site abandonment, but by one year these had begun to senesce and fast-growing successional woody species (particularly Vismia spp.) were common. Standing crop biomass at one year was 773 grams dry weight m-2. 4. Several microhabitat types were present on abandoned farm sites. Grasses and forbs showed no microhabitat preference, whereas successional woody individuals had their best establishment near slash and under fruit trees.
TL;DR: Auxin-responsive cDNA clones have been isolated from a cDNA library prepared from elongating soybean hypocotyl poly(A)(+)RNA and data are suggestive of a close association betwen auxin action and altered gene expression, but a causal relationship is not established.
Abstract: Auxin-responsive cDNA clones have been isolated from a cDNA library prepared from elongating soybean hypocotyl poly(A)(+)RNA. The expression of two such sequences has been assessed by RNA blot hybridization analyses during normal developmental transitions in the soybean hypocotyl and during incubation of sections excised from the region of cell elongation. The concentrations of these poly(A)(+)RNAs are higher in the elongating zone than in the apical and mature zones of the hypocotyl. Both poly(A)(+)RNAs are depleted during incubation of the sections in the absence of auxin. The loss of one of these sequences (pJCW1) is prevented by the addition of auxin to the incubation medium while the other sequence (pJCW2) increases above the initial level in the presence of auxin. The addition of auxin to auxin-depleted tissue in which the sequences are depleted results in rapid accumulation of these poly(A)(+)RNAs; pJCW1 accumulates to the control level while pJCW2 increases well above the control level. These data along with others [Baulcombe, D. C. & Key, J. L. (1980) J. Biol. Chem. 255, 8907-8913] demonstrate directly a highly selective effect of auxin on the expression of a small number of mRNAs in tissues undergoing both cell elongation and cell division in response to auxin. Although the data are suggestive of a close association betwen auxin action and altered gene expression, a causal relationship is not established. It seems highly unlikely, however, that such specific effects of auxin on gene expression are unimportant in auxin physiology.
TL;DR: Daphnia magna, fed mixtures of three sizes of polystyrene particles, retained particles that were smaller than the mesh size of the animals at greater efficiencies than predicted by a sieving model.
Abstract: Surface chemistry of both particles and animals is important in filter feeding at low Reynolds number. Daphnia magna, fed mixtures of three sizes of polystyrene particles, retained particles that were smaller than the mesh size of the animals (1.0 micrometer) at greater efficiencies than predicted by a sieving model. Retention efficiency of the smallest particles (0.5 micrometer) was increased when negative surface charge on the particles was neutralized, and retention was decreased when a nonionic surfactant was, added to reduce wettability.
TL;DR: Previous data on the function of electron transfer proteins must be re-evaluated and new experimental approaches designed before the problem is resolved, according to new information about differences in pyrophosphate metabolism by Desulfovibrio and Desulfotomaculum.
Abstract: Extensive information is available on the enzymology of respiratory sulphate reduction and the structure of electron transfer proteins isolated from the sulphate-reducing bacteria; however, it has not yet been possible to delineate satisfactorily the function of these electron transfer proteins in terms of the enzymes involved in respiratory sulphate reduction. New information about differences in pyrophosphate metabolism by Desulfovibrio and Desulfotomaculum, cellular localizations of electron transfer proteins and enzymes, and the concepts of vectorial electron transfer plus hydrogen cycling suggest that previous data on the function of electron transfer proteins must be re-evaluated and new experimental approaches designed before the problem is resolved. New information on the enzymology of lactate dehydrogenase, pyruvate dehydrogenase, adenylyl sulphate reductase, bisulphite reductase and hydrogenase is presented and discussed in the context of enzyme localization and specifically for electron transfer proteins. The function of cytochrome c3 (Mr = 13000) in the mechanism of the periplasmic hydrogenase and the role of the new [3Fe-3S] non-haem iron centres in electron transfer is emphasized.
TL;DR: Ontogenetic differences in constancy of daytime school locales and migration routes may result from learning, facilitated perhaps by greater overlap of age cohorts in large juveniles, plus stabilizing selection due to greater predation on smaller, behaviourally variable fish.
TL;DR: The chemistry and biology of the ant venom alkaloids from the genera Solenopsis and Monomorium are briefly reviewed in this paper, where the usual 2,6-dialkylpiperidines found in four as yet unstudied species of solenopsis are described.
TL;DR: A geologic study of the late Miocene to Holocene depositional and erosional history of the intermediate-depth Maurice Ewing Bank (MEB) located at the eastern extremity of the Falkland (Malvinas) Plateau, southwest Atlantic Ocean is presented in this article.