Showing papers by "Colorado State University published in 1984"

Atlantic Seasonal Hurricane Frequency. Part I: El Niño and 30 mb Quasi-Biennial Oscillation Influences

Abstract: This is the first of two papers on Atlantic seasonal hurricane frequency In this paper, seasonal hurricane frequency as related to E1 Nino events during 1900–82 and to the equatorial Quasi-Biennial Oscillation (QBO) of stratospheric zonal wind from 1950 to 1982 is discussed It is shown that a substantial negative correlation is typically present between the seasonal number of hurricanes, hurricane days and tropical storms, and moderate or strong (15 cases) El Nin off the South American west coast A similar negative anomaly in hurricane activity occurs when equatorial winds at 30 mb are from an easterly direction and/or are becoming more easterly with time during the hurricane season This association of Atlantic hurricane activity with El Nino can also be made with the Southern Oscillation Index By contrast, seasonal hurricane frequency is slightly above normal in non-El Nino years and substantially above normal when equatorial stratospheric winds blow from a westerly direction and/or are bec

A Comparison of Large and Small Tropical Cyclones

Abstract: In this paper the climatology and structure of, and possible reasons for, tropical cyclones of different sizes are examined. The climatology of tropical cyclone sizes confirms that tropical cyclones of the western North Pacific are characteristically twice as large as their Atlantic counterparts, and also reveals that the typical size of tropical cyclones varies seasonally and regionally and is only weakly correlated with cyclone intensity (maximum surface wind or minimum surface pressure). Rawinsonde composities of large and small tropical cyclones show that large cyclones have much more relative angular momentum (RAM) than small cyclones, while the differences in RAM between intense and weaker cyclones of equivalent size are less. Some of the implications of this observance are discussed, and a hypothesis that cyclones grow as a result of an increased convergence of angular momentum forced by their environment is presented.

A rapid accurate wet oxidation diffusion procedure for determining organic and inorganic carbon in plant and soil samples

Abstract: A method is presented for determining organic carbon content of soils, extracts and plant tissue utilizing an acidic wet oxidation in modified culture tubes; samples containing carbonates are pretreated with dilute acid. Evolved CO2 is trapped in a NaOH solution and quantified titrimetrically. The method described has a range of 0.4–11 mg. carbon and the range can be extended in either direction by modifying the CO2 trapping/titration procedure. This method is as accurate and precise as more time consuming dry oxidation procedures.

Evaluation of Soil Moisture Effects on the Generation and Modification of Mesoscale Circulations

Abstract: The current study provides an evaluation of thermally induced circulation over flat terrain due to nonuniform horizontal distribution of soil moisture availability. Additionally, the effect of soil moisture availability on the thermally induced upslope flow during the daylight hours is examined. The results indicate that in flat terrain, which has a nonhomogeneous moisture availability, the intensity of thermal circulations approaches that of sea-breeze circulations for the case of large contrasts. Even small amounts of water in thesoil, adjacent to dry areas, can still result in a significant mesoscale flow. The upslope flow has been indicated to be perturbed significantly when the moisture availability ii~creases or when the horizontal contrast of soil moisture availability becomes large.

Atlantic Seasonal Hurricane Frequency. Part II: Forecasting its Variability

Abstract: This is the second of two papers on Atlantic seasonal hurricane activity. It is an extension of Part I, which discussed the association of El Nino and the phases of the stratospheric Quasi-Biennial Oscillation (QBO) of equatorial zonal wind with Atlantic seasonal hurricane variability. It is shown how the addition of regional sea-level pressure data from Caribbean basin meteorological stations can be combined with the more global El Nino and QBO information to form a forecast scheme for Atlantic seasonal hurricane activity. Seasonal forecasts might be issued on 1 June of each year and updated prior to the commencement of the most active part of the hurricane season on 1 August. Although this forecast scheme, of necessity, has been developed on dependent data, the expected forecast skill degradation when applied to independent data sets has been estimated. It appears not to be large enough to significantly negate the rather substantial degree of potential forecast skill that is evident in the deve...

Lymphocyte suppression in leprosy induced by unique M. leprae glycolipid

Abstract: Leprosy remains a significant medical and social problem in many developing countries. The varied forms of the disease form a spectrum. At one pole, tuberculoid leprosy, patients develop high levels of cell-mediated immunity which results in the killing and clearing of bacilli in the tissues. At the lepromatous pole, patients exhibit a selective immunological unresponsiveness to antigens of Mycobacterium leprae so that the organisms inexorably multiply in the skin. We have suggested that in lepromatous leprosy one or a small number of unique antigenic determinants present on M. leprae might induce specific suppressor cells that inhibit the reactivity of helper T-cell clones capable of recognizing other specific or cross reactive determinants. Although unique epitopes have been identified by monoclonal antibodies on a small number of M. leprae proteins, the only unique species of antigen present in M. leprae, and not on any other species of mycobacteria so far examined, is a phenolic glycolipid (gly-I). We show here that this unique antigen of M. leprae is capable of inducing suppression of mitogenic responses of lepromatous patients' lymphocytes in vitro and provide evidence that the suppressor T cells recognize the specific terminal trisaccharide moiety.

Exact nonlinear control of large angle rotational maneuvers

Abstract: The rigid body attitude control problem with external torques is transformed into an equivalent linear form implementable by three double integrators. The linearizing transformations themselves are formulated in vector algebra, requiring no integrators for implementation. It is thereby shown that optimal command generation for fast slewing maneuvers can be carried out exactly in the transformed system, together with regulator design without gain scheduling for correction of unmodeled disturbances. In particular, a general rest-to-rest maneuver is computed in closed form, and coupled with a previously obtained exact detumbling maneuver so that arbitrary initial conditions can be accommodated. An illustrative simulation is appended.

Attribution of responsibility for rape: The influence of observer empathy, victim resistance, and victim attractiveness

Abstract: The purpose of the present study was to investigate the influence of a rape victim's physical attractiveness and resistance to rape on subjects' attributions of responsibility for the crime, certainty of the defendant's guilt, and social perceptions of the rape victim and defendant. Subjects' pretrial empathy toward rape victims and rapists was assessed by scores on the Rape Empathy Scale (RES). In addition to significant sex differences in attributions of responsibility for the incident, subjects' pretrial empathy toward rape victims and rapists was predictive of their perceptions of the rape victim, the defendant, and the rape incident. Victim resistance and attractiveness effects were significant in that subjects responded least favorably to the unattractive rape victim, particularly when she resisted the rape by fighting with her attacker. Male subjects and subjects who exhibited low empathy toward the rape victim were more responsive to subtle manipulations of victim resistance and attractiveness than were females and high RES subjects. Several explanations for these results focus on the cognitive and affective responses of subjects. The implications of the study are discussed in relation to societal attitudes toward rape and the role of sexrole stereotyping, which fosters these attitudes.

Soil fungi: Relationships between hyphal activity and staining with fluorescein diacetate

Abstract: The relationship between fungal activity in soil and staining with fluorescein diacetate (FDA) was investigated using Penicillium citrinum and Rhizoctonia solani inoculated into autoclaved and non-sterilized soil, with or without nutrient amendment. Correlations of fungal activity with FDA staining allowed a quantitative relationship between FDA-staining and fungal CO 2 -evolution to be calculated. Results suggest that where nutrient fluxes occur in the soil, correlation between FDA-staining and CO 2 evolution may be useful in assessing fungal contributions to carbon transformations.

Effect of Phosphate Type and Concentration, Salt Level and Method of Preparation on Binding in Restructured Beef Rolls

Abstract: The effect of combinations of phosphate type [tetrasodium pyrophosphate (PP), sodium tripolyphosphate (TPP), sodium tetrapolyphosphate (TTPP), and sodium-hexametaphosphate(HMP)], phosohate concentration (0.125%-0.500%). and salt level (0.6%-2.0%) on the binding in restructured beef rolls was studied. The rolls were prepared either with or without a homogenate that contained all the added salts. Preparation method had little effect on binding. The effectiveness of the phosphates was: PP > TPP > TTPP > HMP. Changes in binding produced by varying phosphate type, phosphate concentration and salt level could be explained in terms of changes in ionic strength and pH. Between 90% and 96% of the variation in binding could be explained in terms of these two variables.

Rhizosphere bacterial population responses to root colonization by a vesicular-arbuscular mycorrh1zal fungus *†

Abstract: Summary A mixture of bacteria and a vesicular-arbuscular mycorrhizal fungus isolated from field-collected sods of blue grama (Bouteloua gracilis (H.B.K.) Griffiths) were tested for their interaction in the rhizosphere of pot-grown blue grama plants. Populations of the inoculated bacterial species and actinomycete populations, as influenced by the presence or absence of Glomus mosseae (Nicol. and Gerd.) Gerdemann and Trappe, were enumerated by dilution plate counts from rhizosphere and non-rhizosphere soil samples. Total bacterial counts and the population of one bacterial species in the non-rhizosphere soil of pots containing plants were significantly greater than in soil of pots without plants. The population of two bacterial species and actinomycetes were not significantly different in the non-rhizosphere soil of both mycorrhizal and non-mycorrhizal plant treatments when compared to the soil of pots without plants. In the rhizosphere of mycorrhizal plants, the total bacterial population and colony counts of one of the four bacterial isolates, when expressed as colony-forming units (CFU) per gram of root dry weight, were significantly reduced compared with controls. The numbers of CFU per gram of rhizosphere soil of one bacterial species were significantly increased by the presence of the mycorrhizal fungus. Although no significant negative correlation was observed between populations of bacterial species in the rhizosphere soils, significant positive correlations between specific bacterial populations depended on whether or not the roots were mycorrhizal.

Partitioning tropical heat and moisture budgets into cumulus and mesoscale components: implications for cumulus parameterization

Abstract: Results from recent heat and moisture budget studies of tropical mesoscale convective systems have been used to partition the total heating in tropical disturbances into cumulus and mesoscale components The mesoscale component refer to that part of tropical cloud systems which contains mesoscale anvil circulations, viz., a mesoscale updraft in an upper-tropospheric cloud shield extending from near the 0°C level to near the 0°C level to near the tropopause and a mesoscale downdraft in the lower troposphere. The cumulus component, which is determined as a residual, consists of contributions from cumulus elements of all sizes, ranging from deep cumulonimbus to shallow cumulus; however, deep cumulus effects predominate in the tropical disturbances studied here. The method of partitioning requires an estimate of the fraction of f of the total rainfall in tropical disturbances produced by mesoscale anvil systems. The total apparent heat source Q1, and moisture sink Q2 of Yanai and others and the mesosc...

Plant-herbivore interactions in a North American mixed-grass prairie : III. Soil nematode populations and root biomass on Cynomys ludovicianus colonies and adjacent uncolonized areas.

Abstract: Summary. Seasonal dynamics of soil nematodes and root biomass were examined from under western wheatgrass (Agropyron smithii) and little bluestem (Andropogon scoparius) from a heavily grazed prairie dog (Cynomys ludovicianus) colony occupied for 5 to 10 years and an adjacent lightly grazed, uncolonized area in Wind Cave National Park, South Dakota, USA. Nematodes were differentiated into classes of plant-parasitic Tylenchida and Dorylaimida and nonparasitic Dorylamida and Rhabditida. Root-feeding nematodes were generally more numerous from A. smithii than from A. scoparius, while nonparasitic populations were not different in soil from beneath the two plant species. Rhabditida, parasitic Dorylaimida and Tylenchida (from A. scoparius only) were more numerous on the prairie dog colony than from the uncolonized site, but nonparasitic Dorylaimida populations did not differ between the two areas. Mean total (live plus dead) root biomass beneath A. scoparius and A. smithii on the prairie dog colony averaged 71% and 81%, respectively, of values from the uncolonized area. Estimated consumption by root-feeding nematodes averaged 12.6% and 5.8% of annual net root production in the upper 10 cm from the prairie dog colony and uncolonized site, respectively. We conclude that, because of microhabitat modification or reductions in plant resistance to nematodes, heavy grazing by aboveground herbivores apparently facilitates grazing by belowground herbivores. Because heavily grazed plants have less roots than lightly grazed or ungrazed plants, the impact of root-feeding nematodes on primary producers is likely to be greatest in heavily grazed grasslands.

A Shortwave Parameterization Revised to Improve Cloud Absorption

Abstract: We present a modification to the parameterization scheme of Stephens which improves on the estimation of shortwave absorption by cloud. In particular, the variation of cloud absorption with solar elevation angle is improved with the modified scheme.

Chemical synthesis and serology of disaccharides and trisaccharides of phenolic glycolipid antigens from the leprosy bacillus and preparation of a disaccharide protein conjugate for serodiagnosis of leprosy.

Abstract: We examined the structural requirements within the species-specific 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl- alpha-L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-L-rhamnopyranose unit of the phenolic glycolipid I antigen of Mycobacterium leprae for binding to anti-glycolipid immunoglobulin M from human leprosy sera. We used chemically defined, partially deglycosylated fragments of phenolic glycolipid I, two other minor M. leprae-specific phenolic glycolipids (those containing 6-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-L-rhamnopyranose and 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-3-O-methyl-alpha- L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-rhamnopyranose units), and phenolic glycolipids from other mycobacteria. Additionally, the trisaccharide of phenolic glycolipid I, the 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2, 3-di-O-methyl-alpha-L-rhamnopyranose, the 6-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranose, and the beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranose disaccharides were synthesized and characterized, and their activities were examined. Only the phenolic glycolipids containing 3,6-di-O-methyl-beta-D-glucopyranosyl at the nonreducing terminus were efficient in binding the anti-glycolipid immunoglobulin M, and the 3,6-di-O-methyl-beta-D-glucopyranosyl-containing di- and trisaccharides were the most effective in inhibiting this binding. Thus, the 3,6-di-O-methyl-beta-D-glucopyranosyl substituent was recognized as the primary antigen determinant in phenolic glycolipid I. With this information, bovine serum albumin containing reductively aminated 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl- L-rhamnose was prepared and shown to be highly active in the serodiagnosis of leprosy. Images

Fission-spectrum Neutrons at a Low Dose Rate Enhance Neoplastic Transformation in the Linear, Low Dose Region (0–10 cGy)

Abstract: SummaryThe neoplastic transformation of C3H 10T1/2 cells induced by fission-spectrum neutrons delivered at a high dose rate is linear up to 40 cGy. Reducing the dose rate increases the frequency of transformation in the low dose region. At a dose rate of 0·086 cGy min−1, the initial part of the induction curve remains linear but it has a slope 9-fold greater than the initial part of the curve at a high dose rate.

Daytime Boundary-Layer Evolution over Mountainous Terrain. Part 1: Observations of the Dry Circulations

Abstract: This paper presents the boundary layer structure which accompanies the development of daytime local wind systems in a broad mountain valley, as revealed by cross sections of potential temperature. It describes how this structure leads to the occurrence of a region of convergence to the downwind side of mountains. Previous studies, based primarily on one-dimensional sounding of potential temperature and horizontal winds, have shown that profiles of static stability and the presence of winds aloft have an important effect on the manner in which daytime, thermally-forced wind systems develop. In the present study, two-dimensional cross sections obtained from aircraft data, vertical soundings and surface mesonet data show several relevant features. In mid to late morning near the surface, for example, upslope winds form in a shallow mixed layer at the underside of the nocturnal inversion layer (cold pool); at elevations above the top of this cold pool, convectively-mixed surface winds exist. The spat...

Pituitary content of gonadotropins and receptors for gonadotropin-releasing hormone (GnRH) and hypothalamic content of GnRH during the periovulatory period of the ewe.

Abstract: Studies were undertaken to determine if the number of hypophyseal receptors for GnRH changes at the time of the preovulatory surge of LH in ewes; Concentrations of LH, FSH, progesterone, and estradiol in serum and concentrations of LH and FSH in pituitary were measured. The content of GnRH in the hypothalamus was also determined. Estrus was synchronized in 35 cross-bred ewes by injecting prostaglandin F2α (PGF2α at 0 and 4 h (7.5 mg each, im) on day 14 of a naturally occurring estrous cycle, followed 30 h later by the injection of estradiol (25 μg in safflower oil, im). Five ewes were killed at each of the following times relative to the first injection of PGF2α: 0, 24, 32, 44, 50, 56, and 96 h. Blood samples were collected throughout the course of the experiment. Concentrations of progesterone in serum decreased markedly by 8 h after PGF2α and were uniformly undetectable (<300 pg/ml) by 34 h. Concentrations of estradiol in serum increased after the injection of estradiol and returned to basal values 10 h...

Grasp and pinch strength in children 5 to 12 years old.

Abstract: The objective of this study was to establish normative data concerning grasp and pinch strength for use by clinicians who are treating children with hand problems. A population of 474 children ages 5 to 12 were tested using the Jamar dynamometer and the Preston pinch guage. Means and standard deviations of all measurements for all subjects were determined. Results of the study indicate that there is a steady increase in both grasp and pinch strength that coincides with the increase in chronological age and development; males are consistently stronger than females across the age range in all tests, although the differences are not striking. Hand dominance was judged not to be an important factor in predicting strength in this population.