Showing papers by "Colorado State University published in 1975"
01 Mar 1975
TL;DR: An approach to the recognition problem ofMultifunctional control of artificial limbs via electromyographic (EMG) actuation is given in terms of deriving a fast parametric-recognition algorithm whereby the autoregressive-moving-average (ARMA) parameters and the Kalman filter parameters of the EMG time series are identified.
Abstract: Multifunctional control of artificial limbs via electromyographic (EMG) actuation requires means for reliably recognizing or distinguishing between the various functions on the basis of the recorded EMG data. Furthermore, constraints of weight, cost, and computation time on practical prosthesis application must be satisfied. An approach to the aforementioned recognition problem is given in terms of deriving a fast parametric-recognition algorithm whereby the autoregressive-moving-average (ARMA) parameters and the Kalman filter parameters of the EMG time series are identified. It is shown that the resulting identified parameters yield sufficient information to discriminate between a small number of upper extremity functions. Problems involved in practical prosthesis control via the present approach and problems of hardware realization are discussed to illustrate the validity of the approach.
366 citations
TL;DR: In this article, an inverse relation between drainage basin area and critical slope of entrenchment applies, and the lower limit of scatter of the data establishes a critical slope area relation, which can be used to identify potentially unstable valley floors.
Abstract: The widespread occurrence of discontinuous gullies in the oil-shale region of northwestern Colorado is of particular concern because of the resulting progressive destruction of the valley floors. Furthermore, the integration of a semi-arid drainage network can cause a rapid increase in the sediment yield of the basin, with subsequent harmful effects downstream. Field work in the Piceance Creek and Yellow Creek drainage basins indicates that these discontinuous gullies developed on oversteepened segments of the valley floors. Although the critical slope of entrenchment is probably related to magnitude of run-off, discharge measurements are not available; therefore, drainage-basin area was selected as the most representative measure of discharge. An inverse relation between drainage-basin area and critical slope of entrenchment applies, and the lower limit of scatter of the data establishes a critical slope-area relation, which can be used to identify potentially unstable valley floors. This relation can help the land manager determine areas of instability where preventive measures can most economically and successfully be undertaken. It is stressed that this particular quantitative relation is applicable only to the Piceance Creek and Yellow Creek drainage basins. In more heterogeneous basins, other variables will need to be included in the analysis; however, the general theory of valley stability will remain applicable.
313 citations
TL;DR: Using time-resolved interferometry, the authors compared the nonlinear wavefront distortion induced by the simultaneous propagation of an intense light beam in pertinent sample materials relative to the known reference material.
Abstract: Using time-resolved interferometry, we have compared the nonlinear wavefront distortion induced by the simultaneous propagation of an intense light beam in pertinent sample materials relative to the known reference material. Utilizing several normalization techniques, these measurements have led to precise values for the nonlinear coefficient n 2 good to 10 percent.
199 citations
TL;DR: Results indicate that even at relatively high H( 2)O potentials, the transport of O(2) to the root surface might be insufficient to meet the plant's respiratory requirements.
Abstract: The solubility of O(2) in polyethylene glycol 4000 and 6000 solutions of varying concentrations was determined iodimetrically (titrimetrically) and electrochemically using a rotating glassy carbon electrode and a PAR Model 174 Polarograph. The titrimetric determination resulted in the formation of an unexpected precipitate at 2% (w/v) polyethylene glycol corresponding to the approximate critical micelle concentration of the two polyethylene glycol homologs. Beyond 5% polyethylene glycol, O(2) concentration was inversely proportional to polyethylene glycol concentration, and was higher in polyethylene glycol 4000 solutions than in polyethylene glycol 6000. The electrochemical data are a direct measure of O(2) transport to the electrode surface, rather than O(2) activity or concentration. Results indicate that even at relatively high H(2)O potentials, the transport of O(2) to the root surface might be insufficient to meet the plant's respiratory requirements.
195 citations
TL;DR: In this article, the authors reviewed the published methods for calculating aboveground net production with the purpose of critically comparing them with each other and with current understanding of primary productivity, and concluded that although all methods were significantly correlated, there were significant differences among the methods in terms of usefulness as discriminators of sites, years, or treatments.
Abstract: Methodology for calculating aboveground net production (ANP) has progressed from a single estimate of total standing crop at the end to an evaluation of multiple categories of biomass (viz. live, recent dead, old dead) by species and considering, with statistical constraints, each peak during the growing season. We have reviewed the published methods for calculating ANP with the purpose of critically comparing them with each other and with current understanding of primary productivity. As a further comparison of methods we have calculated net aboveground production by 13 methods on sets of harvest data collected by the US/IBP Grassland Biome. The data represent a grazed and ungrazed treatment on 10 sites of six grassland types. One to three years of data were available for each site. A hierarchical cluster analysis showed that all methods except one were significantly correlated (r < -0.61). Analysis of variance indicated that although all methods were significantly correlated, there were significant differences among the methods in terms of usefulness as discriminators of sites, years, or treatments. For various utilitarian and theoretical reasons the numbers of methods were reduced to two groups of “best estimators”. One group consisted of two methods involving summation of species peaks, the first utilizing live biomass, the second live + recent dead biomass. The second group comprised three methods using troughpeak analysis on live, live + recent dead, and live + recent dead + old dead biomass. Analysis for linear relations between the “best estimator” methods and 15 abiotic variables showed many significant relationships.
191 citations
TL;DR: In this article, various transport processes between stratosphere and troposphere are described and quantitative estimates are presented of the mass flux between the two hemispheres of the United States and the troposphere.
Abstract: Qualitative descriptions and quantitative estimates are presented of various transport processes between stratosphere and troposphere. The seasonal changes of tropopause heights account for a flux of about 10 percent of the mass of the stratosphere in one hemisphere during the course of 1 yr. This flux is balanced approximately by the seasonal shift of stratospheric air masses between the northern and southern hemispheres. Vertical transport through the Hadley cell transfers approximately 38 percent of the mass equivalent to one hemispheric stratosphere through the tropopause per year. This appears to be the most effective of all transport mechanisms. Large-scale eddies of the scale of cyclones and anticyclones transfer about 20 percent of stratospheric air through the tropopause per year. Small-scale and mesoscale diffusion processes at tropopause level probably account for the transfer of only 1 percent of stratospheric air. These mass flux estimates are in reasonable agreement with observed residence times of stratospheric pollutants.
189 citations
TL;DR: For instance, this article found that nearly two-thirds of the 870 instances of verbal communications were conversations in which people controlled information, and that deception was often the best policy.
Abstract: This exploratory research in the sociology of talk is focused on three questions for analysis: (1) to what extent does verbal information control occur in interaction, (2) what forms of verbal information control are used by people, and (3) what reasons do people give for controlling verbal information? One hundred and thirty (130) dyadic encounters were recorded and analyzed; the "actor" is the respondent and the "other" is the person with whom actor has the conversation. An analysis of these encounters revealed that nearly two-thirds of the 870 instances of verbal communications were talk which controlled information. Frequency tables and typologies delineate (1) forms of information control and (2) reasons for information control. Although most codes of ethics, religious canons, and humanitarian ideals deprecate deception in whatever form, conversations in everyday life are noticeably characterized by forms of deceit ranging from "white lies" to exploitative prevarication. Analysis of dyadic conversations shows that not only are forms of deception frequently employed, they are necessary, even mandatory discursive elements. In everyday conversations, honesty is not always the best policy.
179 citations
TL;DR: In this paper, the basic electron-bombardment ion thruster technology is discussed and a discussion is made general to facilitate the use of this information in all potential applications, and concepts related to electrostatic acceleration are elaborated.
Abstract: Publisher Summary This chapter focuses on the technology of electron-bombardment ion thrusters. The function of the ion source in electric propulsion is to generate an ion current of moderate, but nearly uniform current density, and to do this with low losses of energy and neutrals. The production of ions in an electron-bombardment thruster takes place within the ion or discharge chamber volume. In a typical operation, electrons are emitted by the ion chamber cathode, which is maintained 30–40 V negative of the anode for mercury propellant. The emitted electrons are constrained by the ends of the chamber, which are at cathode potential and by a magnetic field, which is usually approximately parallel to the axis of the ion chamber. This chapter emphasizes the basic thruster technology. The discussion is made general to facilitate the use of this information in all potential applications. Bombardment thrusters have been operated for the most part with mercury propellant, so work with that propellant is emphasized. Theory and experimental performance of ion production is discussed. Concepts related to electrostatic acceleration are elaborated. Basics of neutralization, thruster efflux, and electron emission are also explained.
154 citations
151 citations
TL;DR: Levels of luteinizing hormone (LH), estradiol-17/3 and progesterone were determined by specific radioimmunoassays in sera obtained from Beagle bitches during proestrus, estrus and diestrus and during pregnancy, with a significant decrease between day 28 of pregnancy and one day prior to whelping.
Abstract: Levels of luteinizing hormone (LH), estradiol-17 beta and progesterone were determined by specific radioimmunoassays in sera obtained from Beagle bitches during proestrus, estrus and diestrus. Concentrations of LH (expressed as NIH-LH-SI equivalents) were 2.8 plus or minus 0.1 ng/ml in proestrus, 35.5 plus or minus 10.0 ng/ml during early estrus and 2.2 plus or minus 0.1 ng/ml in early diestrus. Peak levels of estradiol-17beta (68.9 plus or minus 11.0 ng/ml) were detected 24 hr prior to the LH peak, declined rapidly and reached basal levels (17.8 plus or minus 6.3 ng/ml) by five days following the LH peak. Levels of progesterone were 1.7 plus or minus 0.3 ng/ml during proestrus, 3.5 plus or minus 0.3 ng/ml during early estrus and 23.3 plus or minus 2.8 ng/ml on day 5 after the LH peak . Progesterone levels remained elevated through day 28 of diestrus and pregnancy. A significant decrease (p smaller than 0.05) in levels of prosgesterone occurred between day 28 of pregnancy and one day prior to shelping (3.3 plus or minus 1.2 ng/ml, with a further decrease on the day of whelping (1.1 plus or minus 0.2 ng/ml). Levels of estradiol-17beta and LH did not change significantly (p smaller than 0.0k) during diestrus or pregnancy.
134 citations
TL;DR: It was concluded that two types of dysmenorrhea do, in fact, exist and that this study has provided a reliable means of differentiating them and from a therapeutic standpoint, accurate diagnosis of type may be a prerequisite for prescribing appropriate treatment.
TL;DR: Motility was depressed by high and low concentrations of seminal plasma, and with a dried skim milk extender, prefreeze and postfreeze motility was greater in samples containing 20% seminal plasma.
TL;DR: Tissue culture may provide a rapid method for producing sodium chloride tolerant crop plants and several salt tolerant lines of tobacco cells are isolated as a first step toward this goal.
TL;DR: In this article, the equilibrium thermodynamic properties of small clusters of xenon, krypton, and argon atoms, determined from a biased random-walk Monte Carlo procedure, were reported.
Abstract: The present work reports on the equilibrium thermodynamic properties of small clusters of xenon, krypton, and argon atoms, determined from a biased random-walk Monte Carlo procedure. Cluster sizes ranged from 3 to 13 atoms. Each cluster was found to have an abrupt liquid-gas phase transition at a temperature much less than for the bulk material. An abrupt solid-liquid transition is observed for thirteen- and eleven-particle clusters. For cluster sizes smaller than 11, a gradual transition from solid to liquid occurred over a fairly broad range of temperatures. Distribution of number of bond lengths as a function of bond length was calculated for several systems at various temperatures. The effects of box boundary conditions are discussed. Results show the importance of a correct description of boundary conditions. A surprising result is the slow rate at which system properties approach bulk behavior as cluster size is increased.
TL;DR: In this article, the authors examined the social processes involved in disaster warnings which function to elicit evacuation in such threat situations and examined the role of the mass media in forming situational definitions for evacuation.
Abstract: The communication of messages of the impending impact of some natural disaster agent can play a key role in averting natural catastrophe. This article examines the social processes involved in disaster warnings which function to elicit evacuation in such threat situations. These processes and the role of the mass media in forming situational definitions requisite for evacuation are examined in reference to data gathered in Rapid City, South Dakota where on June 9, 1972 a flash flood produced a major disaster.
TL;DR: Hb apparently owes its normal resistance to autoxidation to the isolation of the binding site from electron donors and nucleophiles and not to an unique kind of iron-O 2 bonding, which explains the effects of structural abnormality that render M-type Hbs susceptible to oxidation.
TL;DR: Muscle relaxation and noncontinuous biofeedback were investigated as potential nonpharmaceutical treatments for essential hypertension and it was shown that muscle relaxation has a significant effect upon lowering diastolic and systolic blood pressures between premeasures and postmeasures.
TL;DR: In this paper, the solar wind abundances and O abundance were determined during periods in 1969-1971 when interplanetary flow conditions were quiet, and 17 determinations of solar wind Fe and Si abundances were made.
Abstract: During periods in 1969–1971 when interplanetary flow conditions were quiet, 17 determinations of the solar wind Fe and Si abundances and 7 of the O abundance were made. On the average 〈N(Fe)/N(H)〉 = 5.3 × 10-5, 〈N(Si)/N(H)〉 = 7.6 × 10-5 and 〈N(O)/N(H)〉 = 5.2 × 10-4. Variations from the averages over a total range of factors of ∼4 for O, ∼4 for Si, and ∼ 10 for Fe have have observed. Although Fe and Si abundance variations appear to be correlated, no other element correlation pairs are unambiguously discernible from the present data set.
TL;DR: By utilizing estrogen and progesterone, it appeared possible to mimic the changes occurring in blood hormone levels near puberty, which suggested the possibility of induction of puberty in beef heifers.
Abstract: Colorado State University, s Fort Collins 80521 Summary By utilizing estrogen and progesterone, it appeared possible to mimic the changes occurring in blood hormone levels near puberty This suggested the possibility of induction of puberty in beef heifers Four trials were conducted to test this hypothesis and a fifth to explore the effect of treatment with steroids in induction of estrus in suckling anestrous cows
TL;DR: In this paper, an aerosol generator and wind tunnel system designed for use in aerosol deposition is described, and it is shown that the performance of single horizontal streamlining leaves is similar to that for arrays of leaves under similar flow conditions.
Abstract: An aerosol generator and wind tunnel system designed for use in aerosol deposition is described. Gross deposition on rough pubescent leaves was nearly 7 times greater than on smooth, waxy leaves. Results suggest that aerosol deposition, on a per unit area basis, for single horizontal streamlining leaves is similar to that for arrays of leaves under similar flow conditions. Wind reentrainment of PbCl2 particles was negligible while 2.54 cm of simulated rainfall was sufficient to remove 85 percent of recently applied aerosol.
TL;DR: In this article, the relationship in use by the U. S. Federal Insurance Administration are shown to be reasonable and are recommended for use as approximate guides to estimate flood damage in order to perform feasibility studies.
Abstract: With implementation of the Flood Insurance Act of 1968 many additional local flood protection projects are being considered. Consulting engineers and local agencies need consistent methods to estimate flood damage in order to perform feasibility studies. Federal agencies have a great deal of data and long experience in making damage estimates but no comprehensive guides are available at the local level. Curves of flood damages to different residential structure types are presented. The relationships in use by the U. S. Federal Insurance Administration are shown to be reasonable and are recommended for use as approximate guides. Additional research is recommended and discussion of the paper is invited in order to make additional data available in the literature.
TL;DR: In this paper, the effect of using different character weights upon the same set of OTU's was examined using terpenoid data from seven species ofJuniperus and found that the use of exemplars has small effects, mostly causing the OTU to cluster more loosely when exemplars were included in the computation of the statistical weights.
Abstract: Terpenoid data from seven species ofJuniperus were used to examine:1) the effect of using different character weights upon the same set of OTU’s; 2) the effect of the organization of the initial data base by populations, individuals, and averages on statistical weights and the resulting classification; and3) the effect of the use of exemplars on statistical weights and similarity measures Cophenetic correlation and numerical taxonomy, along with certain relationships well documented for these species, were used to examine these questions Equal weighting of characters, advocated by most numerical taxonomists, gave the most distorted results Thiswas followed by the 1/coefficient of variation, then the weighting of {ie305-01} and finallyF andF-1 weighting producing the highest fidelity to the known similarities The use of either all individuals or random individuals appeared to be better than the use of population averages for some OTU’s and individuals for other OTU’s and much better than the use of population averages only The use of exemplars has small effects, mostly causing the OTU’s to cluster more loosely when exemplars were included in the computation of the statistical weights The use of equal weighting is discussed and strongly discouraged in numerical taxonomy in favor of statistically derived weights
TL;DR: A procedure for sequentially estimating the parameters and orders of mixed autoregressive moving-average signal models from time-series data is presented.
Abstract: A procedure for sequentially estimating the parameters and orders of mixed autoregressive moving-average signal models from time-series data is presented. Identification is performed by first identifying a purely autoregressive signal model. The parameters and orders of the mixed autoregressive moving-average process are then given from the solution of simple algebraic equations involving the purely autoregressive model parameters.
TL;DR: In this paper, the growth rate of the boundary layer thickness over the convex side is almost halved and the skin friction coefficient falls to about 0.9 of the value expected on a plane surface.
Abstract: Measurements are reported for turbulent boundary-layer growth in a prolonged bend where the additional rates of strain produced by streamline curvature influence the turbulent development. The growth rate of the boundary-layer thickness over the convex side is almost halved and the skin friction coefficient falls to about 0.9 of the value expected on a plane surface. The mixing rate on the concave side is increased to about 1.1 times the plane surface value, and the customary evidence of longitudinal rolls appears. These measurements are the first since those of Schmidbauer's (1936) to provide a test of existing curvature correction formulas for curvatures typical of airfoils and turbomachinery without the complications of compressibility. Results have been compared against calculation techniques proposed by Bradshaw (1973), with good agreement.
TL;DR: In this article, the authors compared the properties of the Landau-Lifshitz and Gilbert phenomenological formulations of the two-magnon process and the Bloch-Bloembergen phenomenological description of damping in ferromagnetic resonance.
Abstract: Relaxation rates for the uniform precession mode in ferromagnetic resonance, with general elliptical polarization, have been calculated for several microscopic scattering processes using the spin-wave formalism. These results are compared with the widely used phenomenological formulations for ferromagnetic resonance. The results demonstrate in relatively general terms the specific features of the Landau-Lifshitz and Gilbert phenomenological formulations on the one hand, and of what may be called "intrinsic" confluence processes in the microscopic formulation. These formulations are consistent with the assumption of an intrinsic damping parameter describing the motion of the magnetization vector under sufficiently general conditions. The two-magnon process and the Bloch-Bloembergen phenomenological description of damping in ferromagnetic resonance are not consistent with such an assumption.
TL;DR: Semen from one Angus, two Hereford and three Charolais bulls was frozen at the fast, moderate and slow rates in straws maintained in the horizontal or vertical position, and post-thaw moti l i ty improved as the temperature of the thawing bath was increased from 5 to 55 C.
Abstract: Extended semen from six Hereford bulls was placed in .25-ml Continental straws and frozen in the vertical position. Treatments were arranged factorially with glycerol levels of 5, 7, 9 or 11%; semen cooled from 5 to 1 3 0 C in 3.5 (fast), 20 (moderate) or 40 min (slow); and thawed in water at 5 C for 3 min, 35 C for 12 sec, 55 C for 8 sec, 75 C for 7 sec or 90 C for 5 seconds. Fast freezing resulted in greater postthaw motil i ty than moderate (P < .05) or slow rates (P < .01), regardless of thawing method. Glycerol levels of 7 to 11% provided opt imal survival when averaged over rates of freezing and thawing (P < .05). Post-thaw moti l i ty improved as the temperature of the thawing bath was increased from 5 to 55 C (P < .01). Further increases in thawing bath temperature to 90 C did not enhance survival. The post-thaw motil i ty of spermatozoa frozen rapidly in straws and thawed at 55 to 90 C exceeded that for ampules from split-ejaculates frozen in 1.0-ml ampules (P < .01). Semen from one Angus, two Hereford and three Charolais bulls was frozen in a second study at the fast, moderate and slow rates in straws maintained in the horizontal or vertical position. The final extended semen contained 5, 7, 9 or 11% glycerol; and all semen was thawed in 75 C water for 7 seconds. Fast freezing resulted in post-thaw moti l i ty equal to
TL;DR: The different kinds of information available for B and the mammalian MHCs reflect differences in circumstance, sampling, and technique, and should be regarded as less fundamental than the immunogenetic similarities.
Abstract: B identifies a system of two or more loci which have major effects on hostversus-graft and graft-versus-host reactions. LikeH-2 andHL-A, B encodes lymphocyte antigens which react with alloantibodies and allogenic lymphocytes. Like the mammalian MHCs,B has many alleleic variants. LikeH-2 alleles, some of these are associated with specific differences in immune competence and susceptibility to viral oncogenesis. UnlikeH-2, there is no evidence thatB histocompatibility andB serology represent separable genetic systems. In addition,B is associated with functional differences unknown in mammals. These include a general difference in immune competence and differences in the frequency of herpesvirus lymphoma and in reproductive and general fitness. We conclude that the different kinds of information available forB and the mammalian MHCs reflect differences in circumstance, sampling, and technique, and should be regarded as less fundamental than the immunogenetic similarities. We suggest thatB is the phylogenetic homologue ofH-2 andHL-A.
TL;DR: The increase in plasma free fatty acids associated with fasting was prevented by PGE2 for all diets, but had the most marked effect on rats fed hydrogenated vegetable fat, suggesting regulatory effects of P GE2 on serum cholesterol concentration.
Abstract: Evidence that biosynthesis of prostaglandins (PG) in tissues of animals deficient in essential fatty acids is dependent on the availability of their precursors has been demonstrated. The purpose of this study was to determine the following: ( 1 ) ef fects of dietary linoleate enrichment on PG biosynthesis in rats; (2) effects of exogenous PGE2 and dietary linoleate on plasma free fatty acids and serum cholesterol in fed and fasted rats. Rats were fed three different concentrations of dietary linoleate as beef tallow, hydrogenated vegetable fat, or corn oil. The concentrations of PGEi and PGF2« measured by radioimmunoassay were higher in rats fed the corn oil diet than those fed the beef tallow diet independent of energy status. A decrease in the concentration of PG between fasted and fed rats receiving hydrogenated vegetable fat is discussed in respect to the possible influence of trans isomers of unsaturated fatty acids on the bio synthesis of PG. There were significant effects of fasting on serum cholesterol concen tration regardless of diet and significant interactions among effects of PGE2, fasting, and diet, suggesting regulatory effects of PGE2 on serum cholesterol concentration. The increase in plasma free fatty acids associated with fasting was prevented by PGEa for all diets, but had the most marked effect on rats fed hydrogenated vegetable fat. J. Nutr. 105: 995-1002, 1975.
TL;DR: In this article, relative humidity and temperature information for satellite-observed western Pacific and West Indies summertime cloud clusters, cloud cluster environments, clear regions, typhoons, and pre-typhoon cloud clusters are presented.
Abstract: Relative humidity and temperature information is presented for satellite-observed western Pacific and West Indies summertime cloud clusters, cloud cluster environments, clear regions, typhoons, and pre-typhoon cloud clusters. Information is stratified by weather system, region, and time of day. Data are presented as differences from the Jordan (1958) mean summertime West Indies sounding. Inner weather system deviations of humidity and temperature are also given.