Showing papers by "Purdue University published in 1974"

Television: Technology and Cultural Form

Abstract: Television: Technology and Cultural Form was first published in 1974, long before the dawn of multi-channel TV, or the reality and celebrity shows that now pack the schedules. Yet Williams' analysis of television's history, its institutions, programmes and practices, and its future prospects, remains remarkably prescient. Williams stresses the importance of technology in shaping the cultural form of television, while always resisting the determinism of McLuhan's dictum that 'the medium is the message'. If the medium really is the message, Williams asks, what is left for us to do or say? Williams argues that, on the contrary, we as viewers have the power to disturb, disrupt and to distract the otherwise cold logic of history and technology - not just because television is part of the fabric of our daily lives, but because new technologies continue to offer opportunities, momentarily outside the sway of transnational corporations or the grasp of media moguls, for new forms of self and political expression.

Chemical and biological evolution of nucleotide-binding protein.

Abstract: Three-dimensional alignment of the common nucleotide binding structure in dehydrogenases, kinases and flavodoxins permits the recognition of homologous amino acids when sequence comparisons alone would fail. Minimum base changes per codon can then be used to measure evolutionary distances which suggest that this structure was present during precellular evolution.

Brand Choice Behavior as a Function of Information Load

Abstract: A currently popular position among consumer advocates and many public policy makers is that more product information is better. A 3 (number of brands) × 3 (number of items of information per brand)...

An ultrasensitive vibrating probe for measuring steady extracellular currents.

Abstract: We describe a vibrating probe system for measuring relatively steady electrical current densities near individual living cells. It has a signal-to-noise ratio at least 100 times greater than previously available techniques. Thus it can be used to detect current densities as small as 10 nA/cm2 in serum when a 30-µm diameter probe is vibrated at 200 Hz between two points 30 µm apart, and the amplifier's time constant is set at 10 s. Moreover, it should be generally insensitive to interference by concentration gradients. It has been first used to reveal and study 100-s long current pulses which developing fucoid embryos drive through themselves.

Optimal Control Theory

Abstract: (1976). Optimal Control Theory. The American Mathematical Monthly: Vol. 83, No. 4, pp. 225-239.

The Theory of Stochastic Preference and Brand Switching

Abstract: Strong evidence will be introduced which suggests that brand choice behavior is substantially stochastic. A general theory of stochastic preference is presented and tested. Brand switching data are...

The Exchange Rate and U. S. Agriculture

Abstract: Previous analyses of trade and development problems of U. S. agriculture have neglected the role of exchange rate policy. An attempt is made to understand the role of the exchange rate on these problems in a non-parametric fashion by means of a model of induced technical change. It is argued that the overvaluation of the dollar and the policy measures to combat it aggravated the adjustment problems of U. S. agriculture, especially during the 1950's, and resulted in shifting an important share of the benefits of technical change to the consumer. Moreover the recent devaluation of the dollar constitutes an important structural change for U. S. agriculture.

Hippocampal development in the rat: cytogenesis and morphogenesis examined with autoradiography and low-level X-irradiation.

Abstract: The cytogenesis and morphogenesis of the rat hippocampus was examined with the techniques of 3H-thymidine autoradiography, cell pyknosis produced by low-level X-irradiation, and quantitative histology. The procedure of progressively delayed cumulative labelling was used for autoradiography. Groups of rats were injected with four successive daily doses of 3H-thymidine during non-overlapping periods ranging from birth to day 19. They were killed at 60 days of age, and the percentage of labelled cells was determined. The pyramidal cells of Ammon's horn and the polymorph cells of the dentate gyrus are not labelled postnatally, confirming earlier conclusions of their prenatal origin. In the dentate gyrus, 85% of the granule cells are formed postnatally, with 45% forming during the first week. The majority of the small cells of the dentate molecular layer and of the Ammonic strata oriens, radiatum, and lacunosum-moleculare are formed during the second week. As an aid to locating the proliferative compartments of the hippocampus during development and to characterize the time course of both cell differentiation and morphological development, rats ranging in age from gestation day 17 to postnatal day 103 were killed six hours after one exposure to 200r X-rays, and the pyknotic cells were counted. Cell pyknosis in Ammon's horn reaches a maximal level prenatally and declines rapidly during the early postnatal period. Cell pyknosis in the dentate gyrus reaches its highest level during the second postnatal week and declines gradually with some radiosensitive cells still present in the adult. Immature granule cells are also at their highest level during the second postnatal week, while mature granule cells gradually accumulate to attain asymptotic levels at around two months of age. The alignment of the pyramidal cells to form the characteristic curvature of Ammon's horn occurs shortly after pyramidal cell cytogenesis is completed. Conversely, the sharp fold in the dentate gyrus is apparent from the day of birth onward, before the completion of granule cell cytogenesis. Possible mechanisms for the morphological development of the dentate gyrus along with a consideration of the possible migratory route of granule cell precursors is also discussed.

Intrinsic versus extrinsic cues as determinants of perceived product quality.

Abstract: This study tested a portion of Olson's cue model which hypothesizes that, other things equal, intrinsic cues (e.g., physical product differences) will be stronger determinants of perceived-qua lity judgments than will extrinsic cues (e.g., price or store image). Ninety female undergraduates were randomly assigned to the conditions of a 2X3X3 (Price X Store Image X Hosiery Product Samples) analysis of variance with repeated measures on the intrinsic factor. Results supported the hypothesis; omega-square values revealed that 73% of the total variance was due to intrinsic product sample differences. Additionally, Shapiro's hypothesis that perceived worth would be more strongly related to stated purchase intentions than would perceived quality was supported. Purchase behavior in contemporary American society requires, among other things, that the consumer be able to make judgments and comparisons across products, brands, and services. Such judgments are arrived at by a process in which some or all of the various items of information (i.e., cues) associated with the product, brand, or service are identified, evaluated, and integrated to form a composite judgment. One judgment usually of considerable importance to the consumer is the product's quality, and more than a score of published studies have examined the effects of specific cues on the judgment of perceived quality (cf. Jacoby, Olson, & Haddock, 1971; Olson, 1972). Little thought, however, has been given to developing a conceptual framework for expressing how and when specific cues or types of cues operate to form the composite quality judgment. Until recently, the most notable exception has been Cox (1962), who developed a cue-processing model based upon the notions of predictive and confidence value. Other investigators (Jacoby et al., 1971; Valenzi & Andrews, 1971) have distinguished between intrinsic and extrinsic cues. The former refer to cues which, if changed, would produce a resultant change in the physical product itself (e.g., flavor and aroma cues for beer), while the latter refer to such factors

Induction Machine Analysis for Arbitrary Displacement Between Multiple Winding Sets

Abstract: The steps in t he applied voltages of a three-phase, inverter-induction motor drive system cause undesirable pulsations in motortor By using multiple inverters connected to a multiphase machine with appropriate winding displacements, significant improvement in system performance is possible. The winding displacements required, however, are not necessarily the symmetrical displacements used in standard multiphase machines. This paper sets forth an improved method for analyzing many types of unsymmetrical, as well as symmetrical, multiphase induction machines. The simulation of a 7.5-hp induction machine with two three-phase sets of stator windings fed from two six-step inverters illustrates the application of the method of analysis and shows how the machine torque characteristic may be improved by proper spacing of the winding sets.

A Method for Characterizing the Relation between Nutrient Concentration and Flux into Roots of Intact Plants.

Abstract: A method based on the rate of depletion of a nutrient from solution was developed to characterize nutrient flux of plant roots Nutrient concentration of the solution was measured at a series of time intervals to describe the complete depletion curve An integrated rate equation, based on a Michaelis-Menten model, was developed and fit to the data of the depletion curve using a least-square procedure The equation contained values for V max , the maximum rate of influx; Km , the Michaelis constant; and E , efflux, which were used to describe the relation between solution concentration and net influx rate Models other than Michaelis-Menten could also be used The method uses only one plant or group of plants to obtain data over a range of nutrient concentrations, is adapted particularly to the low concentration range, and measures the concentration below which net influx ceases With this method the plant is in steady state absorption prior to the experiment and continues at this steady state until near the end of the experiment A procedure was also developed to measure uptake rate at constant concentration by adding nutrients to the pot at a constant rate that matched net influx into the root This method also provides a means of measuring diurnal fluctuations in net influx rates

An Exploration of Deception as a Communication Construct

Abstract: Even though most of us lie from time to time, it is really quite surprising how little is known about such behaviors. Through controlled observation and laboratory testing, this study attempted to determine what verbal and nonverbal behaviors were characteristic of intentionally deceptive communicators. Seventy-six videotaped interviews provided a data base for the analysis of 32 dependent measures. In addition to analyses of specific behavioral differences between deceivers and nondeceivers, the authors provide a conceptual framework for the study of deception—predicting that deceivers will exhibit significantly more uncertainty, vagueness, nervousness, reticence, dependence, and unpleasantness than nondeceivers.

Structures for polyinosinic acid and polyguanylic acid

Abstract: X-ray-diffraction analysis of oriented, partially crystalline fibres of polyinosinic acid has resulted in a new molecular model. This model consists of four identical polynucleotide chains related to one another by a fourfold rotation axis. The coaxial helices are righthanded (screw symmetry 23(2)) and have an axial translation per residue h=0.341nm and a rotation per residue t=31.3 degrees . Incorporated in the model are standard bond lengths, bond angles and C-2-endo furanose rings. The nucleotide conformation angles, determined by linked-atom least-squares methods, are orthodox and the fit with the X-ray intensities is good. Each hypoxanthine base is linked to two others by hydrogen bonds involving O-6 and N-1. Further stability may arise from intrachain hydrogen bonds between each ribose hydroxyl group and the phosphate oxygen O-3. If guanine were to be substituted for hypoxanthine in an isogeometrical molecular structure, additional hydrogen bonds could be made between every N-2 and N-7.

Influence of assimilate demand on photosynthesis, diffusive resistances, translocation, and carbohydrate levels of soybean leaves.

Abstract: Rates of net photosynthesis and translocation, CO 2 diffusive resistances, levels of carbohydrates, total protein, chlorophyll, and inorganic phosphate, and ribulose 1,5-diphosphate carboxylase activity were measured in soybean ( Glycine max L. Merrill) leaves to ascertain the effect of altered assimilate demand. To increase assimilate demand, the pods, stems, and all but one leaf (the “source leaf”) of potted plants were completely shaded for 6 or 8 days and the responses of the illuminated source leaf were monitored. Rate of net photosynthesis in the source leaf of the shaded plants was found to increase curvilinearly to a maximum on the 8th day. The source leaf of the control plants (no sink shading) maintained a constant photosynthetic rate during this period. Vapor-phase resistance to CO 2 diffusion did not vary with treatment, but mesophyll (liquid phase) resistance was significantly lower in the source leaf of the shaded plants. Starch concentration in the source leaf of shaded plants decreased more than 10-fold during the 8-day shading period. In this same period, sucrose concentration rose nearly 3-fold. Conversely, in the source leaf of the unshaded plants, starch concentration remained high (23% of leaf dry weight) and sucrose concentration remained very low (1.2%). When measured on the 8th day of treatment, translocation rate, ribulose 1,5-diphosphate carboxylase activity, and inorganic phosphate concentration were found to be significantly higher in the source leaf of the shaded plants than in the control source leaf. When shaded plants were again illuminated, all measured response trends in the source leaf were reversed. These data indicate that assimilate demand has a marked influence on source-leaf photosynthesis and carbohydrate formation and export.

Auditory and Visual Contributions to the Perception of Consonants

Abstract: Perceptual confusions of 16 consonant-vowel (CV) syllables were studied with normal-hearing adults under conditions of auditory-visual presentation at various signal-to-noise (S/N) ratios, as well ...

The function of the Waxy locus in starch synthesis in maize endosperm

Abstract: The soluble adenosine diphosphate glucose-starch glucosyltransferase of maize (Zea mays L.) endosperm uses adenosine diphosphate glucose as a sole substrate, but the starch granule-bound nucleoside diphosphate glucose-starch glucosyltransferase utilizes both adenosine diphosphate glucose and uridine diphosphate glucose. The soluble glucosyltransferase can be bound to added amylose or to maize starch granules that contain amylose. However, binding of the soluble enzyme to the starch granules does not change its substrate specificity to that of the natural starch granule-bound glucosyltransferase. Furthermore, the soluble glucosyltransferase bound to starch granules can be removed by repeated washing without a change in specificity. The bound glucosyltransferase can be released by mechanical disruption of starch granules, and the released enzyme behaves in a manner similar to that of the bound enzyme in several respects. These observations suggest that the soluble and bound glucosyltransferases are different enzymes. The starch granule-bound glucosyltransferase activity is linearly proportional to the number of Wx alleles present in the endosperm. This is compatible with the hypothesis that the Wx allele is a structural gene coding for the bound glucosyltransferase, which is important for the normal synthesis of amylose.