Showing papers by "Clemson University published in 1979"
TL;DR: In this article, a laboratory experiment was conducted to determine whether retention of waterborne sand by salt marsh cordgrass, Spartina alterniflora Loisel, is directly related to the number of stems per unit area.
Abstract: A laboratory experiment was conducted to determine whether retention of waterborne sand by salt marsh cordgrass, Spartina alterniflora Loisel, is directly related to the number of stems per unit area. Waves generated in a trough washed over a sloping beach planted with S. alterniflora sprigs: a range of stem densities (0–108 stems/m2) was examined in separate trials. The amount of sand accumulated after 60 waves is a positive nonlinear function of stem density. The greatest accretion coincided with the highest stem density tested. Shape of the beach profile was also strongly influenced by the number of stems per m2.
206 citations
TL;DR: In this paper, an infinite number of new invariants and related auxiliary equations for the time-dependent harmonic oscillator were derived, and the number of auxiliary equations was shown to be infinite.
180 citations
TL;DR: When eggs differing in specific gravity were processed through an egg-sizing machine and candled for cracks, there was a significance decrease in the number of cracked eggs and a significant increase in percent shell as specific gravity increased.
120 citations
TL;DR: The quantity of non-settleable solids was shown to be related to the quantity of extracellular biopolymers excreted by the microorganisms, which contributes to low clarification efficiencies of the activated sludge process.
102 citations
TL;DR: Hypertension was found to be negatively associated with WAIS Verbal scores for younger but not older subjects, while younger subjects attained higher WAIS Performance scores than did older subjects.
Abstract: This study examined the effects of age and hypertension on WAIS performance. Previous studies have reported that hypertension adversely affects cognitive functioning, but few have considered the influence of hypertension on discrete age groups. Hypertension was found to be negatively associated with WAIS Verbal scores for younger (21 to 39 years) but not older (45 to 65 years) subjects. Further, younger subjects attained higher WAIS Performance scores than did older subjects. Medication history was not associated with performance levels for hypertensives, nor was performance of controls influenced by whether or not they were tested while on a diuretic. When WAIS Performance scores were analyzed for subjects matched on WAIS Verbal scores across age (21 to 39 vs 45 to 65 years) and blood pressure (normotensive vs hypertensive), a significant age by blood pressure interaction was found. The effect of blood pressure on Performance scores was found to be greater for younger than for older subjects. The association between plasma renin activity (PRA) level and WAIS Performance scores was also examined. Contrary to previous findings PRA was not related to Performance scores. The results are discussed in the context of previous hypertension research and their implications for comparisons across age levels.
58 citations
Patent•
24 Sep 1979TL;DR: In this article, an improved process for orthopedic implantation of a prosthesis where the prosthesis has a polymer coating on substantially the entire surface of same that is to be affixed to the bone by bone cement, the polymer coating being substantially completely polymerized and exhibiting a virtually pore free outer surface.
Abstract: An improved process for orthopedic implantation of a prosthesis where the prosthesis has a polymer coating on substantially the entire surface of same that is to be affixed to the bone by bone cement, the polymer coating being substantially completely polymerized and exhibiting a virtually pore free outer surface. After preparation of the bone cavity, a bone cement, preferably a self-curing acrylic is inserted into the bone cavity, after which the precoated prosthesis is properly positioned therein. The polymeric coating on the prosthesis should be compatible with the bone cement to achieve a chemical bond therebetween. A precoated prosthesis is also disclosed and claimed.
52 citations
TL;DR: The performance of some of the breeding lines was variable among the tests but showed that the resistance can be transferred by crosses with commercial cultivars.
Abstract: In 1973,654 soybean lines were field-screened for resistance to pentatomid pests in South Carolina. Twenty-seven lines were selected and tested in 1974 in replicated field plots. None was highly resistant under heavy feeding pressure by Nezara virudula (L.), Acrosternum hilare (Say), and Euschistus spp., with seed damage ranging from 30.2 to 84.2%. Five of these lines and 3 insect resistant plant introductions (PIs) 171451, 227687, and 229358 were tested for development, mortality, and weight gain of N. viridula nymphs confined over pods in the field and under laboratory conditions.
All 3 PIs exhibited resistance to N. viridula in 2 or 3 of the forced-feeding tests. PI229358 was the most consistently resistant in all tests, causing significantly higher mortality, longer development, and lower weight gain for nymphs compared to those on ‘Bragg’. The performance of some of the breeding lines was variable among the tests but showed that the resistance can be transferred by crosses with commercial cultivars.
46 citations
TL;DR: In this article, the integral equation of the scattering was solved exactly for a one-dimensional exponential corrugated potential, and numerical results were presented for a sinusoidal and a triangular profile of small amplitude.
Abstract: The integral equation of the scattering is solved exactly for a one-dimensional exponential corrugated potential. Numerical results are presented for a sinusoidal and a triangular profile of small amplitude. As the "slope" of the exponential increases the intensities given by the hard corrugated wall are approached. The finite slope of the potential has the strong effect of forcing the particles into the specular peak and tends to reduce the effect of multiple scattering.
45 citations
TL;DR: Soybean (Glycine max {L.} Merr.) cultivars were inoculated with Gigaspora gigantea and Glomus mosseae to determine mycorrhizal: cultivar relationships as affected by soil pH.
Abstract: Soybean (Glycine max {L.} Merr.) cultivars were inoculated withGigaspora gigantea andGlomus mosseae to determine mycorrhizal: cultivar relationships as affected by soil pH. The specific cultivarfungal response was dependent on soil pH. Overall cultivar responses in unlimed soil (pH 5.1) were greater forG. gigantea thanG. mosseae. The ‘Bossier’ —G. gigantea combination was particularly responsive in unlimed soil and showed an increase of 10% in shoot length, 35% in shoot dry weight. 75% in root dry weight, and 397% in nodule dry weight over uninoculated controls. Little cultivar response was observed withG. mosseae inoculation in unlimed soil. In limed soil (pH 6.2), the larger responses were obtained withG. mosseae inoculated plants, although inoculation with eitherG. mosseae orG. gigantea appeared effective. In general, nodulation was greater on mycorrhizal roots than on control roots.
43 citations
TL;DR: In this article, a sequential sampling procedure is given for selecting the most probable event from a multinomial distribution, where observations are taken sequentially until the largest count in any cell is equal to N or when the difference between the largest and the next largest cell count are equal to r, where r and N are given positive integers.
Abstract: : A sequential sampling procedure is given for selecting the most probable event from a multinomial distribution. Observations are taken sequentially until the largest count in any cell is equal to N or when the difference between the largest and the next largest cell count is equal to r, where r and N are given positive integers. Probability of a correct selection and expected sample number are given.
43 citations
01 Mar 1979
TL;DR: In this paper, a recursive numerical method has been used to compile a table of percentage points, which extends the range of sample sizes, for which exact results are available, from three to ten.
Abstract: SUMMARY In absence of a general analytical formulation for the distribution of Greenwood's statistic, a recursive numerical method has been used to compile a table of percentage points. This extends the range of sample sizes, for which exact results are available, from three to ten. A procedure for computing P.(x), given n and x, was constructed in two parts. First, maximum use was made of explicit formulations cited previously for n = 2 and n = 3, and for x 3, this last case with a standard trigonometric substitution for an incomplete beta integral appearing in the original formulation of Moran (1953). Second, for n> 3 and x> (n - 1)-1, P.(x) was computed recursively using numerical integration. Moran's recursion, for the hypervolume shared by a regular n-simplex and a concentric n-sphere of general radius (Moran, 1947), translates into (Z,(X))nPn(x) = 1 + j(n+ 1)1 (zn(y))n+2 Pn_1(y) dy
TL;DR: In this paper, a conjugate-gradient optimization method which is invariant to nonlinear scaling of a quadratic form is introduced, which enables certain non-quadratic functions to be minimized in a finite number of steps.
Abstract: A conjugate-gradient optimization method which is invariant to nonlinear scaling of a quadratic form is introduced. The technique has the property that the search directions generated are identical to those produced by the classical Fletcher-Reeves algorithm applied to the quadratic form. The approach enables certain nonquadratic functions to be minimized in a finite number of steps. Several examples which illustrate the efficacy of the method are included.
TL;DR: The general need for this capability in emergency service models as a prerequisite for developing second-generation models that may relate direct outcome measures such as damage, loss of life, and arrests to the managerial decisions is discussed.
Abstract: We describe an extension of Larson's hypercube queuing model to enable it to calculate the probability distributions of travel times. In addition, we discuss the general need for this capability in emergency service models as a prerequisite for developing second-generation models that may relate direct outcome measures such as damage, loss of life, and arrests to the managerial decisions.
TL;DR: In a generalization of Radon's theorem, Tverberg as mentioned in this paper showed that each setS of at least (d+1) (r − 1)+1 points in Rd has anr-partition into (pair wise disjoint) subsetsS =S1 ∪ … ∪Srso that eachn members of the family {convSi∼i-1r have non-empty intersection, where 1<=n<=r.
Abstract: In a generalization of Radon’s theorem, Tverberg showed that each setS of at least (d+1) (r − 1)+1 points inRdhas anr-partition into (pair wise disjoint) subsetsS =S1 ∪ … ∪Srso that\(\bigcap
olimits_i^r {\underline{\underline {}} } _1 \) convSi# O. This note considers the following more general problems: (1) How large mustS σRdbe to assure thatS has anr-partitionS=S1∪ … ∪Srso that eachn members of the family {convSi∼i-1r have non-empty intersection, where 1<=n<=r. (2) How large mustS ∪Rd be to assure thatS has anr-partition for which\(\bigcap
olimits_i^r {\underline{\underline {}} } _1 \) convSr is at least 1-dimensional.
TL;DR: In this paper, triple-triplet energy transfer has been shown to occur from poly(ethylene terephthalate) (PET) units to the 2,6-naphthalenedicarboxylate (2,6ND) monomer units in a series of copolymers, as filament yarns, by an exchange mechanism at 77°K.
Abstract: Triplet–triplet energy transfer has been shown to occur from poly(ethylene terephthalate) (PET) units to the 2,6-naphthalenedicarboxylate (2,6-ND) monomer units in a series of poly(ethylene terephthalate–co–2,6-naphthalenedicarboxylate) (PET–2,6-ND) copolymers, as filament yarns, by an exchange mechanism at 77°K. The radius of the “quenching sphere” has been calculated to be 19.7 A, indicating the presence of triplet energy migration. Photostabilization was observed in the copolymer yarns with the concentration of the monomer dimethyl 2,6-naphthalenedicarboxylate (2,6-DMN) at or above 2 mol %; the rate of phototendering in an air atmosphere was shown to decrease from 2.0 × 10−19% breaking strength loss/quantum absorbed/cm2 in the homopolymer PET to 0.7 × 10−19% breaking strength loss/quantum absorbed/cm2 in the copolymer yarns. The photophysical processes in the monomers, dimethyl terephthalate and 2,6-DMN, were examined by absorption and luminescence studies. The lowest excited singlet and triplet in both monomers were identified to be the 1(π, π*) and 3(π, π*) states, respectively. The phosphorescence of PET was shown to originate from a 3(π, π*) state, while the complex fluorescence spectrum may arise from some oriented aggregates in the polymer matrix. In copolymer yarns, only the fluorescence emission from the 2,6-ND monomer units at 380 nm was observed. The phosphorescence spectra of the copolymer yarns showed phosphorescence emissions from the PET and 2,6-ND monomer units; in addition, delayed fluorescence from the 2,6-ND monomer was also observed.
TL;DR: The poor prediction of hypertensive status from individual neuropsychological test scores was emphasized and readers were cautioned not to conclude that essential hypertensives, as a group, can be characterized as brain damaged.
Abstract: Young adult (X = 29) and middle aged (X = 50) hypertensive and normotensive subjects were compared with respect to seven neuropsychological test scores derived from tests on the Halstead-Reitan battery. Age main effects, with inferior performance for the middle aged subjects, were observed for the localization and time portions of the Tactile Performance Test (TPT) and for the Trail Making A test. The multivariate age effect was significant for the composite of seven scores. A multivariate blood pressure main effect was obtained and main effect blood pressure was significant for the category test; hypertensives made more errors than normotensives. A blood pressure by age interaction was observed for finger tapping scores and the TPT-Memory scores with larger differences between hypertensives and normotensives for the younger than for the middle aged group. Results were discussed in terms of previous studies of age and hypertension with the WAIS, the Primary Mental Abilities Test and serial reacti...
TL;DR: In this article, the authors derive several new invariants for mechanical systems possessing several degrees of freedom, as special cases of the invariants used in quantum treatments of these systems, and include them in the set of invariants that have been used for quantum treatment of mechanical systems.
TL;DR: Bone and fibrous tissue ingrowth into the pores attached the implant to the bone, and a soft tissue-implant interface similar to natural teeth was revealed.
Abstract: Forty-three porous rooted polymethylmethacrylate (PMMA) dental implants were inserted into twenty-four dogs. Successful implants were maintained for up to three years. Histological sections with the implants in situ of implants revealed a soft tissue-implant interface similar to natural teeth. Bone and fibrous tissue ingrowth into the pores attached the implant to the bone. Failures were attributed to mechanical weakness of the implant, thin buccal cortical bone, and excessive implant-gingiva interface.
01 Jan 1979
TL;DR: The more gradual transmission of load from implant to bone and "auto-centering" of implants during operation by pre-coating, are believed to be advantageous over conventional cement fixation method.
Abstract: A study on the feasibility of implants pre-coated with an acrylic bone cement has been performed. Four types of implants, an actual canine femoral prosthesis, a polished steel rod (0.49 cm dia. x 13 cm long) with and without pre-coating, and a sandblasted steel rod with pre-coating were implanted into canine femurs in vitro and in vivo to evaluate the interfacial shear strengths in addition to the bench test. After serial sectioning the samples in discs, push-out tests were made to evaluate the interfacial strengths of cement-bone-implant. The weakest interfacial shear strength was exhibited by the polished rod/cement interface (0.5 MPa) while the strongest was the "old" and "new" cement interface (23.4 MPa). The bone/cement interfacial strength was in between for in vitro (1.17 MPa) and in vivo (1.68 MPa). The shear strength of rod/cement interface increased substantially by sandblasting (6.84 MPa). The microscopic observation of the interface showed somewhat smaller gaps developed for the pre-coated rod than the uncoated rod due to the shrinkage effect. In addition to the overall increase in interfacial strength, the pre-coating may furthermore reduce the setting temperature, the shrinkage, and the amount of monomer released during operation due to the reduced amount of cement at the time of implantation. The more gradual transmission of load from implant to bone and "auto-centering" of implants during operation by pre-coating, are believed to be advantageous over conventional cement fixation method.
TL;DR: The criteria for the initiation of motion for organic detrital sediments appear to follow the same Shields relationship as sand and other uniform inorganic inorganic sediments as mentioned in this paper, and the measurement of particle diameter is replaced with an equivalent diameter determined from fall velocity and density.
Abstract: The criteria for the initiation ofmotion for organic detrital sediments appear to follow the same Shields relationship as sand and other uniform inorganic sediments. The salt marsh tidal creek samples tested include mud particles and stem, leaf, and root fragments of marsh grasses. The measurement of particle diameter is replaced with an equivalent diameter determined from fall velocity and density.
TL;DR: In this article, the cellulolytic activity of Thermomonospora curvata was investigated in municipal solid waste compost and various cellulosic wastes were evaluated for their potential for the induction of cellulase synthesis by Th. curvata under optimal culture conditions.
Abstract: Research is reported on the cellulolytic activity of Thermomonospora curvata, a thermophilic cellulolytic actinomycete prevalent in municipal solid waste compost. Various cellulosic wastes were evaluated for their potential for the induction of cellulase synthesis by Th. curvata and the extent of cellulose degradation under optimal culture conditions. All the substrates tested showed significant degradation of their cellulose content with the exception of sawdust and barley straw. In contrast to Trichoderma viride, cotton fibers were the best substrates for both C/sub 1/ and C/sub x/ cellulase production. Further research is recommended. (JSR)
TL;DR: The results of the present study are consistent with previous results from the laboratory that have found that younger hypertensives differed (relative to controls) from middle aged hypertensive on measures, such as, symptoms reported on the Cornell Medical Index and WAIS Performance scores.
Abstract: This study examined the effects of essential hypertension on measures of anxiety and depression for two age groups of hypertensive (free from hypertension-related pathology and/or cardiovascular disease) and normotensive subjects. Hypertensive subjects had significantly higher State Anxiety scores and Zung Depression scores than did normotensive subjects. These differences between the blood pressure groups were due largely to the scores of the younger hypertensive subjects. The results of the present study are consistent with previous results from our laboratory that have found that younger hypertensives differed (relative to controls) from middle aged hypertensives on measures, such as, symptoms reported on the Cornell Medical Index and WAIS Performance scores. The results of the present study were discussed within the context of age associated differences in response to hypertension and factors that might account for these differences.
TL;DR: In this article, the stress and birefringence in liquid filaments undergoing an extensional flow were measured in an isothermal filament-spinning apparatus and an experimental arrangement was described which, as subsequent analyses show, overcomes the difficulties associated with the measurement of bireringence.
Abstract: The stress and birefringence in liquid filaments undergoing an extensional flow were measured in an isothermal filament-spinning apparatus. In conjunction with these measurements, an experimental arrangement is described which, as subsequent analyses show, overcomes the difficulties associated with the measurement of birefringence in this geometry. The fluids studied were 1 1/2% and 2 1/2% solutions of two polyacrylamides (Separan AP 30 and Separan AP 273) in a 1 : 1 water/glycerol mixture and a 5% solution of polystyrene (Styron 686) in Aroclor 1254. For all solutions studied, the measured birefringence exhibited a non-linear relation to the principal stress difference. In addition, for the polystyrene/Aroclor solution, the birefringence measured in extension was nearly two orders of magnitude higher than the birefringence in shear at comparable deformation rates. These observations imply a greater degree of molecular orientation is produced by the extensional flow than the shear flow and suggest that birefringence data obtained in shear and extension are useful complements to depict a wider range of stress-optical behavior.
TL;DR: Three variants of the classical conjugate-gradient method are presented in this article, and two of these variants are based upon a nonlinear function of a quadratic form.
Abstract: Three variants of the classical conjugate-gradient method are presented. Two of these variants are based upon a nonlinear function of a quadratic form. A restarting procedure due to Powell, and based upon some earlier work of Beale, is discussed and incorporated into two of the variants. Results of applying the four algorithms to a set of benchmark problems are included, and some tentative conclusions about the relative merits of the four schemes are presented.
TL;DR: Eight species of noctuid larvae were tested for susceptibility to a nuclear polyhedrosis virus of the velvetbean caterpillar, Anticarsia gemmatalis, and high dosages were required to kill Heliothis zea, Trichoplusia ni, Pseudoplusio includens, and Spodoptera ornithogalli.
TL;DR: This paper pointed out the limitations of economic analysis and the limited applicability of the conclusions that have been drawn, and argued that economists seem to have made an unrecognized intellectual leap from assuming that the individual has a rational capacity to assuming that all individual behavior had a rational foundation and is therefore subject to logical discourse.
Abstract: The purpose of this chapter is not to downgrade nor to extol the virtue of economic analysis, but rather to reflect on its limitations. In these times, given much professional talk of the expanding domain of economic science and an inclination on the part of some economists to claim that economic analysis has no boundaries, my purpose may seem unusual.1 My concern is not that we economists have said nothing, but that we have lost sight of the limitations of our methods and, thereby, the limited applicability of the conclusions that have been drawn. More specifically, in much modern discussion, economists seem to have made an unrecognized intellectual leap from assuming that the individual has a rational capacity to assuming that all individual behavior has a rational foundation and is therefore subject to logical discourse.
TL;DR: In this paper, a direct relationship exists between rainfall, streamflow and turbidity and the density of nematodes in drinking water, which supports the hypothesis that the worms are not breeding within the water treatment facility but are entering the municipal water system with the raw water.
TL;DR: In this article, a physical method to predict the hand of woven fabrics is introduced, which combines 14 physical parameters which can be objectively measured to calculate a hand value for a fabric in conjunction with a graph of logarithmic values of the 14 hand parameters.
Abstract: A physical method to predict the hand of woven fabrics is introduced. Fourteen physical parameters which can be objectively measured were combined to calculate a hand value for a fabric in conjunction with a graph of logarithmic values of the 14 hand parameters. A practical mill application of this method is suggested as a regular quality control process.