Showing papers by "University of Arkansas published in 1987"

Comparison of physiological responses to maximal arm exercise among able-bodied, paraplegics and quadriplegics

Abstract: Comparison of physiological responses to maximal arm exercise among able-bodied, paraplegics and quadriplegics

Spectrum of squeezing and photocurrent shot noise: a normally ordered treatment

Abstract: The detection of squeezed optical fields generated by intracavity nonlinear-optical interactions is described. The relationship between quantum-statistical properties of the cavity mode and those of the field at a detector placed outside the cavity discussed. The detected field is composed of a source field from the cavity plus a free external field. The free field couples weakly to the cavity so that it is correlated with the source field. The photocurrent spectrum in optical homodyne detection is calculated, and the spectrum of squeezing is defined. This spectrum can be calculated entirely in terms of intracavity fields without requiring knowledge of the correlations between source and free-field contributions in the cavity output. This follows from an explicitly normally ordered, time-ordered treatment of the photodetection problem. Contrasting earlier treatments of photodetection for squeezed fields, in a normally ordered approach, shot noise arises naturally from the self-correlation of photocurrent for pulses. The derived spectrum is converted into nonnormally ordered, non-time-ordered form to recover the results of these earlier treatments and their interpretation of shot noise in terms of local-oscillator quantum noise, signal and quantum noise, and detector-efficiency quantum noise.

A phase II trial of combination chemotherapy in patients with metastatic carcinoid tumors. A Southwest Oncology Group Study.

Abstract: A prospective Phase II trial of combination chemotherapy in patients with metastatic carcinoid tumors was conducted by the Southwest Oncology Group. The therapy included 5-fluorouracil, Adriamycin, cyclophosphamide, and streptozotocin (FAC-S) or the same combination without Adriamycin (FC-S) in patients with heart disease. Seventy-four patients were entered and two were ineligible. Sixty-nine of the 72 were histologically reviewed. Six patients were declared ineligible after this review. Fifty-six patients received FAC-S, and nine received FC-S (one patient was inevaluable). The response rates were 31% and 22%, respectively. The median survival of all patients was 10.8 months. The analyses of various clinical and histologic parameters indicated that responses were more common in patients with gastrintestinal carcinoids; there was also a tendency toward shorter survival in patients with tumors that had a higher mitotic rate or the atypical and/or undifferentiated histologic pattern. The FAC-S combination can produce objective responses in patients with metastatic carcinoid tumors, but these are generally partial and brief. It was also concluded that currently available chemotherapy is inadequate.

Shifted 1/N expansion for the Hulthén potential.

Abstract: The shifted 1/N expansion method is applied to the Hulth\'en potential. Numerical results for the energy values for n=1--5 states are presented. For l=0 states, the agreement between our results and the exact analytical solution is excellent.

Osmotic Adjustment in Cotton (Gossypium hirsutum L.) Leaves and Roots in Response to Water Stress.

Abstract: The relative magnitude of adjustment in osmotic potential (ψs) of water-stressed cotton (Gossypium hirsutum L.) leaves and roots was studied using plants raised in pots of sand and grown in a growth chamber. One and three water-stress preconditioning cycles were imposed by withholding water, and the subsequent adjustment in solute potential upon relief of the stress and complete rehydration was monitored with thermocouple psychrometers. Both leaves and roots exhibited a substantial adjustment in ψs in response to water stress with the former exhibiting the larger absolute adjustment. The osmotic adjustment of leaves was 0.41 megapascal compared to 0.19 megapascal in the roots. The roots, however, exhibited much larger percentage osmotic adjustments of 46 and 63% in the one and three stress cycles, respectively, compared to 22 and 40% in the leaves in similar stress cycles. The osmotically adjusted condition of leaves and roots decreased after relief of the single cycle stress to about half the initial value within 3 days, and to the well-watered control level within 6 days. In contrast, increasing the number of water-stress preconditioning cycles resulted in significant percentage osmotic adjustment still being present after 6 days in roots but not in the leaves. The decrease in ψs of leaves persisted longer in field-grown cotton plants compared to plants of the same age grown in the growth chamber. The advantage of decreased ψs in leaves and roots of water-stressed cotton plants was associated with the maintenance of turgor during periods of decreasing water potentials.

Pollen as an Indicator of Long-distance Movement of Heliothis zea (Lepidoptera: Noctuidae)

Abstract: Adult male bollworm, Heliothis zea (Boddie), moths were collected from sex pheromone traps located in Arkansas and were examined for pollen. Pollen was found on 68.3% of the moths, primarily on the proboscis or eye area. Pollen of false mesquite, Calliandra , and ape's earring, Pithecellobium , were found on moths during each of 2 yr. Neither plant occurs in Arkansas; Calliandra's closest distribution to Arkansas is south central Texas, and Pithecellobium occurs in south Texas near the Mexican border. The presence of these pollens on H. zea indicates immigration from at least 750 km to the Arkansas capture sites.

Socialization Effects of Retail Work Experience on Shopping Orientations

Abstract: The shopping orientations of consumers have been the subject of a significant amount of study in the marketing and retailing literature (c.f., Darden and Reynolds 1971; Darden and Ashton 1975; Korgaonkar 1981; Lumpkin and Greenberg 1982). While the literature will be more completely reviewed below, it can be generally concluded that consumers' orientations toward shopping have been found consistently to be among the most important predictors of both individual store and store-type choice behavior. Very little is known, however, about the factors which explain individual differences in shopping orientations. The purpose of this study is to investigate the socializing influence of one unique determinant of shopping orientations: Retail Work Experience. Consumer researchers generally agree that experience plays an important role in the determination of future behavior. The experience which has been of primary interest to marketers is that which individuals acquire while acting as consumers. However, experience acquired in other contexts can also impact consumer behavior. An individual's experiences emerge from the multitude of roles that he or she performs, and these experiences are thought to contribute to specific as well as general knowledge. It appears reasonable, for example, that the automotive engineer approaches the purchase of an automobile with a different orientation than the "typical" car buyer. Here, both the individual's consumer and work experiences are important in determining the person's consumption behavior; the individual's work experiences

Intake, digestion, passage rate and serum prolactin in growing dairy steers fed endophyte-infected fescue with noninfected fescue, clover or wheat straw.

Abstract: Growing Holstein steers were used in two Latin-square experiments to determine the effects of supplementation of endophyte-infected fescue hay diets with other forages on intake, digestion, passage rate and serum prolactin concentration. In Exp. 1, five steers (average weight of 186 kg) were fed ad libitum amounts of endophyte-infected and noninfected fescue hays (I and NI, respectively) of similar quality in 0:1, 1:3, 1:1, 3:1 and 1:0 proportions. Total dry matter (DM) intake as a percentage of body weight (BW) linearly decreased .0055% for each 1% increase in dietary I (P less than .05). Dry matter intakes with 100% I and 100% NI diets were 2.13 and 2.72% of BW, respectively. Total tract digestion of neutral detergent fiber (NDF) increased linearly (P less than .05) with increasing I (66.0, 65.9, 66.3, 68.1 and 69.6%). Ruminal passage rate of particulates changed linearly (P less than .05) and quadratically (P less than .10) as I in the diet increased (3.5, 3.4, 2.6, 2.8 and 2.8%/h), while serum prolactin concentration and rectal temperature decreased linearly (P less than .05). In Exp. 2, four steers (average weight of 137 kg) were given ad libitum amounts of wheat straw (WS) or .73% of BW of clover hay (C) at 0800 and free access to either I or NI at 1600. Total intake as a percentage of BW was greatest for C with NI (3.04), intermediate for WS with NI (2.70) and lowest for C with I (2.30) and WS with I (2.23; P less than .05). Fescue intake (percentage of BW) was lowest (P less than .05) for C with I (1.56) and higher (P less than .05) for WS with NI (2.63) than WS with I (2.12); fescue intake for C with NI (2.33) was intermediate (P greater than .10) to WS with NI and WS with I. The results are interpreted to indicate that increasing the dietary level of I depressed intake linearly and markedly. Intake of diets high in I appears to be lower than can be explained only by ruminal-fill factors. When animals that are consuming basal I diets are provided access to nontoxic, high-quality forage, changes in intake may differ from those with basal diets of nontoxic forage.

BSKNN as a self-pumped phase conjugator

Abstract: Self-pumping has been observed in a cerium-doped Ba2−xSrxK1−yNayNb5O15 (BSKNN) crystal at four argon-ion laser wavelengths. Phase-conjugate reflectivities as high as 30% were measured with response times inversely proportional to the 0.5 power of the input intensity. The response time for beam fanning in the crystal was determined to be inversely proportional to the 0.82 power of the input intensity.

Adolescent pubertal status and affective family relationships: A multivariate assessment.

Abstract: This research attempted to more adequately dimensionalize the study of affective family relations during adolescent pubertal maturation by employing a multivariate approach. Fifty-one families responded to an assessment battery consisting of a series of questionnaires designed to measure affective relations between parents and their adolescent children. Families were classified into prepubertal, transpubertal, or postpubertal groups according to their modal response on pubertal status criteria. A stepwise discriminant analysis was performed to identify measures that maximize between groups differences. Based on this analysis, a correct classification rate of 70% was achieved for all families. The two significant discriminant functions that emerged indicate that differences in family relationships are due to the transformation of mother-adolescent and father-adolescent relations. The pattern of results replicate those of other researchers and provide elaborations concerning the affective nature of family relations during adolescence.

Tumorigenic responses to lindane in mice: potentiation by a dominant mutation

Abstract: Obese mottled yellow Avy/a, lean pseudoagouti Avy/a and lean black a/a (YS X VY) F-1 hybrid female mice were fed diet containing 160 p.p.m. lindane (gamma-hexachlorocyclohexane) for 6, 12, 18 or 24 months. Clara cell hyperplasia was present in a majority of the mice after six months of lindane ingestion; however, more yellow mice (77%) than pseudoagouti (50%) or black (56%) mice had developed this lesion. Continued ingestion of lindane increased the incidence of Clara cell hyperplasia and resulted in similar prevalences in the three phenotypes. Lung tumors associated with lindane ingestion for 24 months were found only in yellow (19%) and pseudoagouti (14%) mice but not in the black mice. Prevalences of hepatocellular adenomas and carcinomas were very low (less than 10%) in untreated pseudoagouti and black mice. Lindane ingestion for 24 months resulted in an hepatocellular adenoma prevalence of 12% in pseudoagouti mice and 3% in black mice; comparable hepatocellular carcinoma prevalences were 5% and 1%. Among yellow mice fed lindane diet for 24 months, adenoma prevalence was 35% (9% among untreated controls) but carcinoma prevalence was only 17% (13% among controls). The tumorigenic responses evoked by lindane feeding in the lean pseudoagouti Avy/a mice but not in the black a/a mice indicate, for the first time, that the Avy gene itself, in the absence of obesity, sensitizes cells to transformation. The greater prevalence of hepatocellular adenomas in obese yellow Avy/a than in lean pseudoagouti Avy/a mice implicates obesity-associated factors in tumor promotion. Similarly, the increased prevalence of hepatocellular carcinomas in untreated obese yellow Avy/a mice, as compared to lean pseudoagouti mice, implicates obesity-associated factor as favoring histiotypic progression of liver tumors. Thus, the Avy gene not only sensitizes cells to respond to tumorigenic stimuli but also, by the induction of obesity, enhances promotion and progression of transformed cells.

On the occurrence of transient puffs in a rotary kiln incinerator simulator I. Prototype solid plastic wastes

Abstract: In the operation of practical rotary kiln incinerators, the hazardous waste charge is often introduced in drums or containers in a batch mode. The ensuing transient condition, caused by the rapid devolatilization of waste materials, can momentarily deplete or displace local levels of excess oxygen in the kiln, resulting in heavy transient loadings of unburned gaseous and particulate hydrocarbons (here denoted as "puffs") leaving the kUn. This system upset must then be handled by an afterburner and subsequent air pollution control devices downstream. Such an overcharging or transient condition may even result in unacceptably low destruction of principal organic hazardous constituents (POHC) and the formation of products of incomplete combustion (PIC). A 73-kW (250,000-Btu/h) rotary kiln simulator was designed and constructed to provide engineering insight into the chemical and physical parameters associated with failure mode conditions. To this end, a statistically designed parametric investigation was und...

The impact of split bond ratings on risk premia

Abstract: Interest rates for bonds are negatively correlated with credit ratings assigned by agencies such as Moody's Investor Service and Standard & Poor's. Still in dispute is whether or not the ratings themselves convey information that is reflected in prices, hence interest rates in the bond markets. Disagreement between these two agencies' ratings leads to “split” ratings, and in this paper, the authors use the phenomenon of split ratings to assess whether or not ratings have a separate impact on bond prices. The results indicate that a downside split appears to have greater bond yield impact than an upside split. The findings are inconsistent with bond market efficiency, at least in the strong form. The market considers the quality of a split-rated bond to reflect the lower of the two ratings. Finally, the symmetry of the results with respect to the ratings agencies indicates that neither agency has more influence than the other in determining bond yields.

Adsorption of lutein from soybean oil on silicic acid I. Isotherms

Abstract: Adsorption of lutein from crude soybean oil miscella on dispersed silicic acid resulted in three different Freundlich type isotherms, depending on the amount of adsorbent used. Normally, changing the amount of adsorbent gives a new point on the same isotherm. Further investigation of the lutein adsorption revealed that addition of 1% isopropanol to the hexane solvent and deactivation of the silica acid with water decreased lutein adsorption. Purification of the lutein resulted in increased adsorption, indicating that triglyceride was competing for adsorption sites. The triglyceride competition was confirmed by calculating an adsorption isotherm for triglyceride from crude soybean oil miscella. Use of silicic acid as a column rather than dispersed yielded multiple isotherms for lutein adsorption based on the amount of adsorbent used. Also, lutein adsorption on columns was concentrated at the entrance to the column. Experiments showed that lutein adsorption was not due to partitioning between bound triglyceride and hexane solvent.

The type three ordinary chondrities: A review

Abstract: The ordinary chondrites are the largest group of meteorites, and the type 3 ordinary chondrites are those which experienced only very mild parent metamorphism; their study provides a unique means of studying the first solid material to from in the early solar system which is either free from the effects of mild metamorphism, or in which the effects of mild metamorphism can be distinguished from primary, nebular effects. In this paper we list all known type 3 ordinary chondrites and references to their study, their compositional data and data relating to the metamorphic history. We review current theories on their formation and the effects of metamorphism, with emphasis on quantitative considerations. Studies on the thermoluminescence properties of these meteorites, which have provided many new insights into their metamorphic history, are reviewed. Some of the least metamorphosed meteorites show evidence for aqueous alteration, which provides a link between the type 3 ordinary chondrites and objects containing water in various forms the carbonaceous chondrites, comets and planets with ‘wet’ mantles.

A vacuum benthos sampler suitable for diverse habitats

Abstract: The vacuum benthos sampler consists of a vacuum chamber equipped with a collecting net connected to the intake of a 12 volt pump, a battery, and a standpipe. Contents of the standpipe are vacuumed while substrate is removed and washed with the exhaust hose. The vacuum chamber is designed for rapid changing of nets during replicate sampling. This sampler is equally efficient in flowing and standing water. It was more effective than a modified Hess sampler for collecting a large variety of benthos from flowing (ca 0.25–0.75 m/s) riffles. Required operation time is variable, but 93% of invertebrates caught in 10 min were captured in the first 5 min during our tests, and there was a 94% mean recovery of released organisms during 10 min of subsequent operation. Advantages over previous suction samplers include interception of organisms before they pass through a pump, return of outlet water to the standpipe, capability of sampling in shallow (20–30 mm) water, and that it can be carried and operated by one person.