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Showing papers by "Purdue University published in 1984"


Journal ArticleDOI
TL;DR: In this paper, it is shown that ability can be conceived in two ways: high or low with reference to the individual's own past performance or knowledge, or competence relative to that of others, and that a gain in mastery alone does not indicate high ability.
Abstract: Achievement behavior is denned as behavior directed at developing or demonstrating high rather than low ability. It is shown that ability can be conceived in two ways. First, ability can be judged high or low with reference to the individual's own past performance or knowledge. In this context, gains in mastery indicate competence. Second, ability can be judged as capacity relative to that of others. In this context, a gain in mastery alone does not indicate high ability. To demonstrate high capacity, one must achieve more with equal effort or use less effort than do others for an equal performance. The conditions under which these different conceptions of ability function as individuals' goals and the nature of subjective experience in each case are specified. Different predictions of task choice and performance are derived and tested for each case. In this article, predictions of task choice, performance, and subjective experience in experimental achievement settings are derived, and relevant evidence is examined. An intentional view of behavior (Dennett, 1978) is adopted. In this, action is construed as a rational attempt to attain goals or incentives. In commonsense terms, individuals' actions serve to achieve purposes efficiently or economically. In the terms of games theory, action maximizes

3,902 citations


Journal ArticleDOI
TL;DR: This implementation of the Algebraic Reconstruction Technique appears to have a computational advantage over the more traditional implementation of ART and potential applications include image reconstruction in conjunction with ray tracing for ultrasound and microwave tomography.

1,539 citations


Journal ArticleDOI
TL;DR: According to stereotypic beliefs about the sexes, women are more communal (selfless and concerned with others) and less agentic (self-assertive and motivated to master) than men.
Abstract: According to stereotypic beliefs about the sexes, women are more communal (selfless and concerned with others) and less agentic (self-assertive and motivated to master) than men. These beliefs were hypothesized to stem from perceivers' observations of women and men in differing social roles: (a) Women are more likely than men to hold positions of lower status and authority, and (b) women are more likely than men to be homemakers and are less likely to be employed in the paid work force. Experiments 1 and 2 failed to support the hypothesis that observed sex differences in status underlie belief in female communal qualities and male agentic qualities. Experiment 3 supported the hypothesis that observed sex differences in distribution into homemaker and employee occupational roles account for these beliefs. In this experiment, subjects perceived the average woman and man stereotypically. Female and male homemakers were perceived as high in communion and low in agency. Female and male employees were perceived as low in communion and high in agency, although female employees were perceived as even more agentic than their male counterparts. Experiments 4 and 5 examined perceptions that might account for the belief that employed women are especially agentic: (a) A double burden of employment plus family responsibilities did not account for this belief, and (b) freedom of choice about being employed accounted for it reasonably well.

1,538 citations


Journal ArticleDOI
TL;DR: Some of the principles of vitrification are reviewed, the current state of the art is described, how a practical vitrification scheme might work, and how the principles relate to and illuminate the principles and practices of freezing are noted.

1,080 citations


Journal ArticleDOI
TL;DR: In this article, the major antioxidant activity in the non-hydrolyzed extract was caused by flavonol glycosides, chlorogenic acid (7.1 × 10−4 mol/kg of seed) and caffeic acid (6.6 × 10 −3 m/kg).
Abstract: Chia (Salvia sp) seeds were investigated as a source of natural lipid antioxidants. Methanolic and aqueous extracts of defatted chia seeds possessed potent antioxidant activity. Analysis of 2 batches of chia-seed oils demonstrated marked difference in the fatty acid composition of the oils. In both batches, the oils had high concentrations of polyunsaturated fatty acids. The major antioxidant activity in the nonhydrolyzed extract was caused by flavonol glycosides, chlorogenic acid (7.1 × 10−4 mol/kg of seed) and caffeic acid (6.6 × 10−3 m/kg). Major antioxidants of the hydrolyzed extracts were flavonol aglycones/kaempferol (1.1 × 10−3 m/kg), quercetin (2.0 × 10−4 m/kg) and myricetin (3.1 × 10−3 m/kg); and caffeic acid (1.35 × 10−2 m/kg). Two methods were used to measure antioxidant activities. Both were based on measuring bleaching ofβ-carotene in the coupled oxidation ofβ-carotene and linoleic acid in the presence of added antioxidants.

937 citations


Journal ArticleDOI
TL;DR: For instance, this article examined various components of gender stereotypes to determine their interrelationship and their influence relative to gender label and found that information about one stereotype component can implicate other components.
Abstract: Various components of gender stereotypes were examined in three studies to determine their interrelationship and their influence relative to gender label. In the first two experiments, male and female college students were given information about gender and either role behaviors or traits and were asked to assess the probability that the stimulus person possessed other gender-related characteristics. In the third experiment, each of four gender stereotype components was presented in a within-subjects design and subjects made judgments about each other component. Results indicate that (a) information about one stereotype component can implicate other components; (b) specific component information may outweigh gender identification; and (c) components differ in their ability to implicate other components of gender stereotypes, with physical appearance playing a dominant role. The significance of these findings in understanding the structure and operation of gender stereotypes is discussed. Stereotypes play an important role in human judgment, and investigators have shown sustained interest in exploring the content and consequences of such judgments. From Lippman's (1922) early and insightful analysis of the "pictures in our heads," through the work of Katz and Braly (1933), Allport (1954), Campbell (1967) and others, stereotypes have continued to hold the interest of social scientists concerned with ways in which we judge and misjudge members of recognizable groups. In recent years, interest in the topic has accelerated, with new attention focused both on the general nature of stereotypes as well as on specific content categories (Hamilton, 1979, 1981; Miller, 1982). At the general level, investigators are increasingly coming to conceptualize stereotypes as one particular instance of more general cognitive processes (Ashmore D Hamilton, 1979;McCauley,

897 citations


Journal ArticleDOI
TL;DR: A conserved fourteen-residue segment consisting of an Asp-Asp sequence flanked by hydrophobic residues has been found in retroviral reverse transcriptases, suggesting this span as a possible active site or nucleic acid recognition region for the polymerases.
Abstract: Possible alignments for portions of the genomic codons in eight different plant and animal viruses are presented: tobacco mosaic, brome mosaic, alfalfa mosaic, sindbis, foot-and-mouth disease, polio, encephalomyocarditis, and cowpea mosaic viruses. Since in one of the viruses (polio) the aligned sequence has been identified as an RNA-dependent polymerase, this would imply the identification of the polymerases in the other viruses. A conserved fourteen-residue segment consisting of an Asp-Asp sequence flanked by hydrophobic residues has also been found in retroviral reverse transcriptases, a bacteriophage, influenza virus, cauliflower mosaic virus and hepatitis B virus, suggesting this span as a possible active site or nucleic acid recognition region for the polymerases. Evolutionary implications are discussed.

850 citations



Journal ArticleDOI
TL;DR: In this article, the results of computer simulations used to determine the domains of applicability of the first-order Born and Rytov approximations in diffraction tomography for cross-sectional (or three-dimensional) imaging of biosystems are shown.
Abstract: In this paper, the results of computer simulations used to determine the domains of applicability of the first-order Born and Rytov approximations in diffraction tomography for cross-sectional (or three-dimensional) imaging of biosystems are shown. These computer simulations were conducted on single cylinders, since in this case analytical expressions are available for the exact scattered fields. The simulations establish the first-order Born approximation to be valid for objects where the product of the relative refractive index and the diameter of the cylinder is less than 0.35 lambda. The first-order Rytov approximation is valid with essentially no constraint on the size of the cylinders; however, the relative refractive index must be less than a few percent. We have also reviewed the assumptions made in the first-order Born and Rytov approximations for diffraction tomography. Further, we have reviewed the derivation of the Fourier Diffraction projection Theorem, which forms the basis of the first-order reconstruction algorithms. We then show how this derivation points to new FFT-based implementations for the higher order diffraction tomography algorithms that are currently being developed.

590 citations


Journal ArticleDOI
TL;DR: In this paper, it is shown that the means of acquisition of information form part of its representation in mind, that recognition varies with the similarity of procedures in acquisition and test, and that transfer between tasks varies with a degree of correspondence of underlying procedures.

564 citations


Journal ArticleDOI
TL;DR: In this article, some heuristic rules for dispatching Automatic Guided Vehicles (AGVs) in a job shop environment are presented, which are useful for assigning priorities to work stations requesting the services of a vehicle for material pickup.
Abstract: SUMMARY Hardware failures notwithstanding, the ability of an automated system operating according to promised potential is dependent upon the operational control measures in force. In this paper, some heuristic rules for dispatching Automatic Guided Vehicles (AGVs) in a job shop environment are presented. The rules are useful for assigning priorities to work stations requesting the services of a vehicle for material pickup. The likely effects of these rules on the performance of a job shop are postulated. Simulation results to demonstrate the effects of these rules arc also presented.


Journal ArticleDOI
TL;DR: It is shown that the ascent procedure can be viewed as a generalization of both the Chu-Liu-Edmonds directed spanning tree algorithm and the Bilde-Krarup-Erlenkotter ascent algorithm for the plant location problem.
Abstract: The Steiner tree problem on a directed graph (STDG) is to find a directed subtree that connects a root node to every node in a designated node setV. We give a dual ascent procedure for obtaining lower bounds to the optimal solution value. The ascent information is also used in a heuristic procedure for obtaining feasible solutions to the STDG. Computational results indicate that the two procedures are very effective in solving a class of STDG's containing up to 60 nodes and 240 directed/120 undirected arcs. The directed spanning tree and uncapacitated plant location problems are special cases of the STDG. Using these relationships, we show that our ascent procedure can be viewed as a generalization ofboth the Chu-Liu-Edmonds directed spanning tree algorithm and the Bilde-Krarup-Erlenkotter ascent algorithm for the plant location problem. The former comparison yields a dual ascent interpretation of the steps of the directed spanning tree algorithm.

Journal ArticleDOI
TL;DR: It is shown that the edge location is related to the so-called ``Christoffel numbers'' and is compared with Sobel and Hueckel edge detectors in presence and absence of noise.
Abstract: A new method for locating edges in digital data to subpixel values and which is invariant to additive and multiplicative changes in the data is presented For one-dimensional edge patterns an ideal edge is fit to the data by matching moments It is shown that the edge location is related to the so-called ``Christoffel numbers'' Also presented is the study of the effect of additive noise on edge location The method is extended to include two-dimensional edge patterns where a line equation is derived to locate an edge This in turn is compared with the standard Hueckel edge operator An application of the new edge operator as an edge detector is also provided and is compared with Sobel and Hueckel edge detectors in presence and absence of noise

Journal ArticleDOI
M. Lema1, O. Mitchell1
TL;DR: In this paper, a color image coding system that uses absolute moment block truncation coding of luminance and chroma information is presented, which shows reasonable performance with bit rates as low as 2.13 bits/pixel.
Abstract: A new quantization method that uses the criterion of preserving sample absolute moments is presented. This is based on the same basic idea for block truncation coding of Delp and Mitchell but it is simpler in any practical implementation. Moreover, output equations are those for a two-level nonparametric minimum mean square error quantizer when the threshold is fixed to the sample mean. The application of this method to single frame color images is developed. A color image coding system that uses absolute moment block truncation coding of luminance and chroma information is presented. Resulting color images show reasonable performance with bit rates as low as 2.13 bits/pixel.

Journal ArticleDOI
TL;DR: It is shown that median filtering an arbitrary level signal to its root is equivalent to decomposing the signal into binary signals, filtering each binary signal to a root with a binary median filter, and then reversing the decomposition.
Abstract: Median filters are a special class of ranked order filters used for smoothing signals Repeated application of the filter on a quantized signal of finite length ultimately results in a sequence, termed a root signal, which is invariant to further passes of the median filter In this paper, it is shown that median filtering an arbitrary level signal to its root is equivalent to decomposing the signal into binary signals, filtering each binary signal to a root with a binary median filter, and then reversing the decomposition This equivalence allows problems in the analysis and the implementation of median filters for arbitrary level signals to be reduced to the equivalent problems for binary signals Since the effects of median filters on binary signals are well understood, this technique is a powerful new tool

Journal ArticleDOI
TL;DR: Examination of the rat CCK gene revealed a suggested transcriptional control sequence analogous to the "TATA" sequence located 33 nucleotides upstream from a proposed transcriptional start site.
Abstract: Poly(A) RNA was isolated from a rat medullary thyroid carcinoma that exhibited high levels of immunoreactive cholecystokinin (CCK). Double-stranded cDNA was synthesized from the poly(A) RNA and inserted into the Pst I site of pBR322. Bacterial colonies containing CCK cDNA were identified using the hybridization probe d(T-C-C-A-T-C-C-A-N-C-C-C-A-T-G-T-A-G-T-C). The sequence of the probe was deduced from the known amino acid sequence of porcine CCK-8, Asp-Tyr-Met-Gly-Trp-Met-Asp-Phe-NH2. The nucleotide sequence of the cDNA complementary to the mRNA of rat preprocholecystokinin was determined. The cDNA contains 33 nucleotides in the 5'-noncoding region, 199 nucleotides in the 3'-noncoding region, and 345 nucleotides coding for a precursor to CCK, which is 115 amino acids (Mr, 12,826). Examination of the rat CCK gene revealed a suggested transcriptional control sequence analogous to the "TATA" sequence located 33 nucleotides upstream from a proposed transcriptional start site. The amino acid sequence of CCK-39 is flanked by both amino-terminal and carboxyl-terminal extensions. Analysis of CCK mRNA showed that it is approximately equal to 750 nucleotides long. CCK mRNA of the rat brain and intestine appeared to be identical in size to the CCK mRNA of the carcinoma.


Journal ArticleDOI
TL;DR: It is shown that a two-dimensional curve defined parametrically in terms of rational degree n polynomials in t can be expressed implicitly as a degree n POlynomial in z and y and it is demonstrated that a “bi-m-ic” parametric surface can be written implicitly as an implicit polynomial of degree 2m2.
Abstract: The following two problems are shown to have closed-form solutions requiring only the arithmetic operations of addition, subtraction, multiplication and division: (1) Given a curve or surface defined parametrically in terms of rational polynomials, find an implicit polynomial equation which defines the same curve or surface. (2) Given the Cartesian coordinates of a point on such a curve or surface, find the parameter(s) corresponding to that point. It is shown that a two-dimensional curve defined parametrically in terms of rational degree n polynomials in t can be expressed implicitly as a degree n polynomial in z and y. It is also demonstrated that a “bi-m-ic” parametric surface (where e.g., m = 3 for bicubic) can be expressed implicitly as a polynomial in x, y, z of degree 2m2. The degree of a rational bi-m-ic surface is also shown to be 2m2. The application of these results to finding curve and surface intersections is discussed.

Journal ArticleDOI
TL;DR: No significant change in PAL activity was observed in either resistant or susceptible combinations with H. maydis, suggesting that PAL and CoA ligase are not coordinately regulated in interactions involving this fungus.
Abstract: Phenylalanine ammonia-lyase (E.C. 4.3.1.5) (PAL) and hydroxycinnamate:CoA ligase (E.C. 6.2.1.12) activities were measured in extracts from maize mesocotyls resistant and susceptible to Helminthosporium maydis and resistant to H. carbonum . CoA ligase activity increased in response to infection with H. maydis in both the resistant and susceptible cultivars. Activity began to increase between 6 and 9 h after inoculation and in the resistant cultivar continued to increase throughout a 48-h period. In susceptible cultivars activity ceased to increase at approximately 12 h after inoculation. The results demonstrate that the increase in CoA ligase activity is detectable as early as the onset of penetration by the fungus. No significant change in PAL activity was observed in either resistant or susceptible combinations with H. maydis , suggesting that PAL and CoA ligase are not coordinately regulated in interactions involving this fungus. Neither enzyme was found to change as a result of inoculation of any cultivar with H. carbonum .


Journal ArticleDOI
TL;DR: On considere le probleme de Cauchy pour l'equation d'onde semi lineaire (ο 2 /∂t 2 -Δ) as discussed by the authors,

Journal ArticleDOI
TL;DR: In this article, the uniqueness of (0.1) was shown to imply the existence of LP(M) on a manifold if every L p harmonic function on the manifold is constant and every nonnegative L p subharmonic function on M is constant.
Abstract: defined on M. To ensure a uniqueness property on equation (0.I) it is necessary to res t r ic t f to lie in a suitable function space. Some of the most natural spaces are those consisting of L p functions on M, denoted by LP(M), where integration is defined with respect to the Riemannian measure. In this setting, uniqueness of (0.1) means that if fELP(M) for some O

Journal ArticleDOI
TL;DR: It is shown that a critical level of myocardial blood flow is required to restore ability of the heart to function as a pump after prolonged CPR, and that a drug that increases flow improves resuscitation efforts.

Journal ArticleDOI
TL;DR: Experimental tests of the model indicate that each protein has a unique Z value and that Z is directly proportional to the molecular weight of a series of proteins when 60% formic acid is used as the mobile phase additive.

Book ChapterDOI
TL;DR: This article reviewed a fairly extensive history in social psychology, focusing on the cognitive theories of persuasion, which are designed to account for the attitude and belief change that occurs in people who are exposed to relatively complex messages that consist of a position advocated by a communicator.
Abstract: Publisher Summary This chapter discusses the end-products of social psychological processes It reviews a research on a fairly extensive history in social psychology––persuasion Testifying to the present dominance of cognitive analyses, the cognitive theories of persuasion are concentrated and demonstrate the fruitfulness of these formulations The social psychological perspectives are developed to be useful to practitioners The theories of persuasion are designed to account for the attitude and belief change that occurs in people who are exposed to relatively complex messages that consist of a position advocated by a communicator Some of the limitations of the cognitive emphasis of most contemporary theories of persuasion consider several viewpoints that emphasize motivation as cognition The mathematically formulated combinatorial models are reviewed, which have explanatory value primarily in relation to the effects of the content of the persuasive message The applications of persuasion theory to more practical concerns are also described in the chapter Theories that have elaborated the cognitive mediation of persuasion are also considered in the chapter

Journal ArticleDOI
TL;DR: The Reference Record created on 2005-11-18, modified on 2016-08-08 as discussed by the authors was used for the verification of probabilite structures and vibration properties of vibration properties.
Abstract: Keywords: probabilites ; structures ; vibration ; methodes de : calcul Reference Record created on 2005-11-18, modified on 2016-08-08

Journal ArticleDOI
TL;DR: The amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus and CPMV, a plant virus, were compared to conclude that the proteinases encoded by these viruses are probably cysteine proteinases, mechanistically related, but not homologous to papain.
Abstract: The amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus (CPMV), a plant virus, were compared. Good homology was found between CPMV and the picornaviruses in the region of the picornavirus 2C (P2-X protein), VPg, 3C pro (proteinase) and 3D pol (RNA polymerase) regions. The CPMV B genome was found to have a similar gene organization to the picornaviruses. A comparison of the 3C pro (proteinase) regions of all of the available picornavirus sequences and CPMV allowed us to identify residues that are completely conserved; of these only two residues, Cys-147 and His-161 (poliovirus proteinase) could be the reactive residues of the active site of a proteinase with analogous mechanism to a known proteinase. We conclude that the proteinases encoded by these viruses are probably cysteine proteinases, mechanistically related, but not homologous to papain.

Journal ArticleDOI
TL;DR: An algorithm that produces the shortest edit sequence transforming one string into another is presented and is optimal in the sense that it generates a minimal covering set of common substrings of one string with respect to another.
Abstract: The string-to-string correction problem is to find a minimal sequence of edit operations for changing a given string into another given string. Extant algorithms compute a longest common subsequence (LCS) of the two strings and then regard the characters not included in the LCS as the differences. However, an LCS does not necessarily include all possible matches, and therefore does not produce the shortest edit sequence. An algorithm that produces the shortest edit sequence transforming one string into another is presented. The algorithm is optimal in the sense that it generates a minimal covering set of common substrings of one string with respect to another. Two improvements of the basic algorithm are developed. The first improvement performs well on strings with few replicated symbols. The second improvement runs in time and space linear to the size of the input. Efficient algorithms for regenerating a string from an edit sequence are also presented.

Journal ArticleDOI
TL;DR: An empirical pepsin digestion method, first reported in 1981, which simulates the digestion values found in children, is developed and used to analyze wheat, maize, rice, millet, and sorghum and certain processed samples of millet and Sorghum.
Abstract: We have shown previously that sorghum is highly digestible in the rat. However, other workers have shown that sorghum is much less digestible than wheat, maize, and rice in young children. Because the rat does not show these digestibility differences, we developed an empirical pepsin digestion method, first reported in 1981, which simulates the digestion values found in children. In this report the method has been improved and used to analyze wheat, maize, rice, millet, and sorghum and certain processed samples of millet and sorghum. The pepsin digestion values parallel those found in children for wheat, maize, rice, and sorghum. In addition, a processed sorghum product that gave a high digestion value in children also gave a high value with the in vitro pepsin method.