Showing papers by "Florida State University published in 1990"

Information technology implementation research: a technological diffusion approach

Abstract: Based on the innovation and technological diffusion literatures, promising research questions concerning the implementation of a production and inventory control information system material requirements planning: MRP are identified and empirically examined. These questions focus on the interaction of managerial tasks with the information technology and the resulting effect on the adoption and infusion of that technology. Using a random sample of manufacturing firms across the United States, we find that this interaction does indeed affect the adoption of MRP, though it does not seem to affect MRP infusion. These results support the notion that though rational decision models may be useful in explaining information technology adoption, political and learning models may be more useful when examining infusion.

Oxygenation-sensitive contrast in magnetic resonance image of rodent brain at high magnetic fields.

Abstract: At high magnetic fields (7 and 8.4 T), water proton magnetic resonance images of brains of live mice and rats under pentobarbital anesthetization have been measured by a gradient echo pulse sequence with a spatial resolution of 65 x 65-microns pixel size and 700-microns slice thickness. The contrast in these images depicts anatomical details of the brain by numerous dark lines of various sizes. These lines are absent in the image taken by the usual spin echo sequence. They represent the blood vessels in the image slice and appear when the deoxyhemoglobin content in the red cells increases. This contrast is most pronounced in an anoxy brain but not present in a brain with diamagnetic oxy or carbon monoxide hemoglobin. The local field induced by the magnetic susceptibility change in the blood due to the paramagnetic deoxyhemoglobin causes the intra voxel dephasing of the water signals of the blood and the surrounding tissue. This oxygenation-dependent contrast is appreciable in high field images with high spatial resolution.

State Lottery Adoptions as Policy Innovations: An Event History Analysis

Abstract: Two types of explanations of state government innovation have been proposed: internal determinants models (which posit that the factors causing a state government to innovate are political, economic, and social characteristics of a state) and regional diffusion models (which point toward the role of policy adoptions by neighboring states in prompting a state to adopt). We show that the two are conceptually compatible, relying on Mohr's theory of organizational innovation. Then we develop and test a unified explanation of state lottery adoptions reflecting both internal and regional influences. The empirical results provide a great degree of support for Mohr's theory. For the empirical analysis, we rely on event history analysis, a form of pooled cross-sectional time series analysis, which we believe may be useful in a wide variety of subfields of political science. Event history analysis may be able to explain important forms of political behavior (by individuals, organizations, or governments) even if they occur only rarely.

The cysteine switch: a principle of regulation of metalloproteinase activity with potential applicability to the entire matrix metalloproteinase gene family.

Abstract: The general applicability of the "cysteine-switch" activation mechanism to the members of the matrix metalloproteinase (MMP) gene family is examined here. All currently known members of the MMP gene family share the characteristic that they are synthesized in a latent, inactive, form. Recent evidence suggests that this latency in human fibroblast collagenase (HFC) is the result of formation of an intramolecular complex between the single cysteine residue in its propeptide domain and the essential zinc atom in the catalytic domain, a complex that blocks the active site. Latent HFC can be activated by multiple means, all of which effect the dissociation of the cysteine residue from the complex. This is referred to as the "cysteine-switch" mechanism of activation. The propeptide domain that contains the critical cysteine residue and the catalytic domain that contains the zinc-binding site are the only two domains common to all of the MMPs. The amino acid sequences surrounding both the critical cysteine residue and a region of the protein chains containing two of the putative histidine zinc-binding ligands are highly conserved in all of the MMPs. A survey of the literature shows that many of the individual MMPs can be activated by the multiple means observed for latent HFC. These observations support the view that the cysteine-switch mechanism is applicable to all members of this gene family. This mechanism is unprecedented in enzymology as far as we know and offers the opportunity for multiple modes of physiological activation of these important enzymes. Since conditions in different cells and tissues may match those necessary to effect one of these activation modes for a given MMP, this may offer metabolic flexibility in the control of MMP activation.

Soluble human complement receptor type 1: in vivo inhibitor of complement suppressing post-ischemic myocardial inflammation and necrosis

Abstract: The complement system is an important mediator of the acute inflammatory response, and an effective inhibitor would suppress tissue damage in many autoimmune and inflammatory diseases. Such an inhibitor might be found among the endogenous regulatory proteins of complement that block the enzymes that activate C3 and C5. Of these proteins, complement receptor type 1 (CR1; CD35) has the most inhibitory potential, but its restriction to a few cell types limits its function in vivo. This limitation was overcome by the recombinant, soluble human CR1, sCR1, which lacks the transmembrane and cytoplasmic domains. The sCR1 bivalently bound dimeric forms of its ligands, C3b and methylamine-treated C4 (C4-ma), and promoted their inactivation by factor I. In nanomolar concentrations, sCR1 blocked complement activation in human serum by the two pathways. The sCR1 had complement inhibitory and anti-inflammatory activities in a rat model of reperfusion injury of ischemic myocardium, reducing myocardial infarction size by 44 percent. These findings identify sCR1 as a potential agent for the suppression of complement-dependent tissue injury in autoimmune and inflammatory diseases.

Multiple modes of activation of latent human fibroblast collagenase: evidence for the role of a Cys73 active-site zinc complex in latency and a "cysteine switch" mechanism for activation.

Abstract: Latent human fibroblast collagenase (HFC) can be activated by a variety of seemingly disparate means. In addition to the well-characterized activation by trypsin and organomercurial compounds, the enzyme can be activated to various extents by surfactants such as sodium dodecyl sulfate, by chaotropic ions such as SCN-, by disulfide compounds such as oxidized glutathione, by sulfhydryl alkylating agents such as N-ethylmaleimide, and by oxidants such as NaOCl. The underlying basis for these activations is the modification, exposure, or proteolytic release of the Cys73 residue from its habitat in the latent enzyme where it is thought to be complexed to the active-site zinc atom. This residue is not accessible for reaction with small molar excesses of dithionitrobenzoate in native, latent HFC. However, on addition of EDTA, this residue becomes fully exposed and is quantitatively labeled. All modes of activation of latent HFC are believed to involve the dissociation of Cys73 from the active-site zinc atom and its replacement by water, with the concomitant exposure of the active site. This is thought to be the primary event that precedes the well-known autolytic cleavages that are observed following the appearance of collagenase activity. The dissociation of Cys73 from the zinc atom in the latent enzyme "switches" the role of the zinc from a noncatalytic to a catalytic one. This "cysteine switch" mechanism of regulation may be applicable to the entire collagenase gene family.

A comparison of the vegetation response to rainfall in the Sahel and East Africa, using normalized difference vegetation index from NOAA AVHRR

Abstract: This article presents the results of a study of the relationship between rainfall and Normalized Difference Vegetation Index (NDVI) in East Africa and the Sahel. Monthly data for the years 1982 to 1985 have been analyzed. We have evaluated NDVI-rainfall relationships by vegetation type, using the major formations described by White (1983). In the article, a comparison of the differential response of vegetation growth to rainfall in the two study regions is emphasized. The most important conclusions of our research are as follows: Two possible explanations of this last conclusion are suggested: above this threshold, rainfall is no longer the limiting factor in vegetation growth and/or NDVI is not a good indicator of vegetation growth. The latter is a likely possibility since NDVI directly reflects photosynthetic activity and becomes a poor indicator of biomass (i.e., growth) as high canopy densities are reached. The NDVI-rainfall relationship for East Africa is markedly similar to the relationship between NDVI and Leaf Area Index demonstrated by Sellers (1985) and Asrar et al. (1984).

Aleph: a detector for electron-positron annihilations at Lep

Abstract: Process-centred Software Engineering Environments (PSEE) are the most recent generation of environments supporting software development activities. Most of PSEE are based on mechanisms promoting enforcement and automation of process activities. In this kind of mechanisms the process models are prescribed in a detailed and complete way. But the experience shows that supporting processes is more concerned with the flexibility of guidance offered during the process performance than with enforcement of a collection of predefined process models. In this paper, we present a solution to support strategic processes in a PSEE by providing a flexible guidance during process enactment.

Effects of Different Resource Additions of Species Diversity in an Annual Plant Community

Abstract: A commonly observed phenomenon in plant communities is that the ad- dition of a limiting resource leads to an increase in productivity and a decrease in species diversity. We tested the hypothesis that the mechanism underlying this pattern is a dis- proportionate increase in mortality of smaller or shade-intolerant species in more produc- tive sites caused by reduction of light levels. We added water and/or one of three nutrients (nitrogen, phosphorus, and potassium) to a 1 st-yr old-field community dominated by weedy annuals and measured effects on productivity, species composition, diversity, and light levels after one growing season. Diversity was not clearly related to productivity in this experiment. Watering increased productivity, but, contrary to expectations, had no effect on density of surviving plants, species diversity, or abundance of low-growing species. Almost all the increase in biomass with watering was due to a positive response by Ambrosia artemisiifolia, an upright annual that was the most common species in the canopy in all treatments. The addition of nitrogen had only a small positive effect on productivity, but strongly decreased density of surviving plants, species diversity, and abundance of most low-growing species. Only Ambrosia increased in abundance with nitrogen addition. The phosphorus and potassium additions had little effect on the community. We suggest that the high mortality and low diversity in the nitrogen addition plots, but not in the more productive watered plots, was due to limitation by nitrogen earlier than limitation by water during the growing season. The consequence was earlier canopy closure and greater mortality due to light limitation.

A stack-based resource allocation policy for realtime processes

Abstract: The stack resource policy (SRP) is a resource allocation policy which permits processes with different priorities to share a single runtime stack. It is a refinement of the priority ceiling protocol (PCP), which strictly bounds priority inversion and permits simple schedulability tests. With or without stack sharing, the SRP offers the following improvements over the PCP: (1) it unifies the treatment of stack, reader-writer, multiunit resources, and binary semaphores; (2) it applies directly to some dynamic scheduling policies, including earliest deadline first (EDF), as well as to static priority policies; (3) with EDF scheduling, it supports a stronger schedulability test; and (4) it reduces the maximum number of context switches for a job execution request by a factor of two. It is at least as good as the PCP in reducing maximum priority inversion. >

Artificial neural network classification using a minimal training set - Comparison to conventional supervised classification

Abstract: Recent research has shown an artificial neural network (ANN) to be capable of pattern recognition and the classification of image data. This paper examines the potential for the application of neural network computing to satellite image processing. A second objective is to provide a preliminary comparison and ANN classification. An artificial neural network can be trained to do land-cover classification of satellite imagery using selected sites representative of each class in a manner similar to conventional supervised classification. One of the major problems associated with recognition and classifications of pattern from remotely sensed data is the time and cost of developing a set of training sites. This reseach compares the use of an ANN back propagation classification procedure with a conventional supervised maximum likelihood classification procedure using a minimal training set. When using a minimal training set, the neural network is able to provide a land-cover classification superior to the classification derived from the conventional classification procedure. This research is the foundation for developing application parameters for further prototyping of software and hardware implementations for artificial neural networks in satellite image and geographic information processing.

Descending pathways to the spinal cord, III: Sites of origin of the corticospinal tract.

Abstract: The somata of corticospinal neurons were labeled with horseradish peroxidase that had been applied to a hemisection of the spinal cord at the C1-C2 junction in 22 species of mammals. After tetramethylbenzidine processing, with and without counterstaining with cresyl violet or neutral red, the labeled cells in systematic sets of sections throughout the cerebral cortex were plotted and counted. Several morphological features of the corticospinal cells were examined including their cell type, number, density, concentration, laminar distribution, and their distribution across the cortical surface. The results show that the labeled corticospinal neurons were invariably layer V pyramidal cells. However, in many mammals they were found to be stacked one above the other within layer V, sometimes many neurons deep. Despite the concentration of corticospinal neurons within layer V, many unlabeled neurons were also present within the layer throughout the extent of the labeled region. The results also indicate that at least two spatially distinct regions of neocortex originate corticospinal fibers in each of the animals in the sample. In addition to these two regions, a third segregated region is present in the cortex of primates and an apparently different third region is present in the cortex of Glires ((Rodentia and Lagomorpha)). The third region of corticospinal cortex in primates is located on the lateral surface of the cortex in prosimians and New World monkeys and is buried in the caudal bank of the inferior arcuate sulcus in Old World monkeys. The results also show a predominantly contralateral corticospinal tract in all but 4 of the 22 mammals in the sample. Although these 4 mammals are each members of the order Insectivora, a less modified member of the same order possessed the predominantly contralateral projection of most mammals, hence denying the notion that a predominantly ipsilateral tract is a characteristic of Insectivora.

Rethinking feminist organizations

Abstract: This article analyzes feminist organizations as a species of social movement organization. It identifies 10 dimensions for comparing feminist and nonfeminist organizations or for deriving types of feminist organizations and analyzing them. The dimensions are feminist ideology, feminist values, feminist goals, feminist outcomes (for members and society), founding circumstances, structure, practice, members and membership, scope and scale, and external relations (legal-corporate status, autonomy, funding, and network linkages). I argue that many scholars judge feminist organizations against an ideal type that is largely unattainable and that excessive attention has been paid to the issue of bureaucracy versus collectivism to the neglect of other organizational qualities. The varieties of ideology, form, and strategy that feminist organizations embody should be analyzed in relation to outcomes for women, the women's movement, and society. As has recently begun to occur, feminist scholars are encouraged to cl...

Theoretical model of discrete tone generation by impinging jets

Abstract: A new feedback mechanism is proposed for discrete tone generation by impinging jets. It is suggested that the feedback is achieved by upstream-propagating waves associated with the lowest-order intrinsic neutral wave modes of the jet flow. These wave modes have well-defined radial and azimuthal pressure and velocity distributions, which are determined by the mean flow of the jets in the case of the Kelvin-Helmholtz instability waves. The model proposed here allows the prediction of the average Strouhal number of impingement tones as a function of the jet Mach number.

Changing metaphors and beliefs: A master switch for teaching?

Abstract: (1990). Changing metaphors and beliefs: A master switch for teaching? Theory Into Practice: Vol. 29, Metaphors We Learn By, pp. 122-127.

Westward Motion of Mesoscale Eddies

Abstract: Since the pioneering work of Nof, the determination of the westward drift of mesoscale eddies under the planetary (beta) effect has been a recurrent theme in mesoscale oceanography, and several different formulae have been proposed in the literature. Here, recpatiulation is sought, and, within the confines of a single-layer model, a generalized formula is derived. Although it is similar to Nof's, the present formula is established from a modified definition and with fewer assumptions. It also recaptiulates all other formulae for the one-layer model and applies to a wide variety of situations, including cases when the vortex develops a wake of Rossby waves or undergoes axismmetrization. Following the derivation of the formula, a physical interpretation clarifies the migration mechanism, which can be divided between a self-induced propulsion and a reaction from the displaced ambient fluid. Numerical simulations with primitive and geostrophic equations validate the formula for a variety of length sc...

Control of marine fish production

Abstract: In the trophic-dynamic hypothesis, biomass production was assumed limited by factors that control energy transfer. An analysis using trophic-dynamic models applied to ocean data, however, leads to a rejection of that hypothesis and supports a hypothesis that carnivorous fish production is controlled by the amount of new N annually incorporated into phytoplankton biomass and transferred through food webs. For an average 2.5 trophic transfers from phytoplankton to fish in environments ranging from oceanic to northeast North American coastal waters, N transfer efficiency was a constant 0.28 while C transfer efficiency increased nonlinearly from 0 to an asymptotic value of 0.16. Fish production was more sensitive to variations in phytoplankton production in oligotrophic than in eutrophic marine environments as a result of a nonlinear decrease in f, the ratio of new to total production, as primary production decreased.

Integration of Spatial Markets

Abstract: Studies of spatial market integration draw their implications from a theory which assumes that there are no intraregional transport costs. An alternative theory is offered, based on the assumptions that buyers and sellers are spatially dispersed and intraregional transport costs are significant. This implies that the market is a linked oligopoly (or oligopsony) and that market integration tests are tests of alternative oligopoly price formation processes. For example, collusive basing-point pricing produces results typically assumed to imply efficiently integrated markets, while competitive FOB pricing does not. The theoretical implications are illustrated with an analysis of hog prices in Canada.

Method for preparation of taxol using an oxazinone

Abstract: Process for the preparation of a taxol intermediate comprising contacting an alcohol with an oxazinone having the formula: ##STR1## wherein R 1 is aryl, substituted aryl, alkyl, alkenyl, or alkynyl; R 2 is hydrogen, ethoxyethyl, 2,2,2-trichloroethoxymethyl or other hydroxyl protecting group; and R 3 is aryl, substituted aryl, alkyl, alkenyl, or alkynyl; the contacting of said alcohol and oxazinone being carried out in the presence of a sufficient amount of an activating agent under effective conditions to cause the oxazinone to react with the alcohol to form a β-amido ester which is suitable for use as an intermediate in the synthesis of taxol.

Effects of bacterial exopolymer adhesion on the entrainment of sand

Abstract: Flow velocity required to erode a bed of acid‐washed sand is increased by intergranular adhesion resulting from growth of the benthic marine bacterium Al‐teromonas atlantica. In general, we find that either pure exopolymer alone or exopolymer generated during in situ growth increases erosion resistance of fine quartz sand. Moreover, the degree of erosion resistance increases in proportion to the concentration of exopolymer‐component uronic acids, which in turn is dependent on relative nitrogen content of peptone‐based growth media. Specifically, we observe that approximately 100 nmol of exopolymer or 1.5 nmol of component uronic acids generated by in situ bacterial growth under nitrogen‐rich conditions per gram of dry sediment can effectively double seawater‐flume flow velocity required for initiation of transport of otherwise noncohesive, 125–177 μm quartz grains. This maximal effect corresponds to an estimated adhesive force that exceeds submerged particle weight by an order of magnitude and ex...

Airborne measurements of dimethylsulfide, sulfur dioxide, and aerosol ions over the Southern Ocean South of Australia

Abstract: Vertical distributions of dimethylsulfide (DMS), sulfur dioxide (SO2), aerosol methane-sulfonate (MSA), non-sea-salt sulfate (nss-SO42-), and other aerosol ions were measured in maritime air west of Tasmania (Australia) during December 1986. A few cloudwater and rainwater samples were also collected and analyzed for major anions and cations. DMS concentrations in the mixed layer (ML) were typically between 15–60 ppt (parts per trillion, 10−12; 24 ppt=1 nmol m−3 (20°C, 1013 hPa)) and decreased in the free troposphere (FT) to about <1–2.4 ppt at 3 km. One profile study showed elevated DMS concentrations at cloud level consistent with turbulent transport (‘cloud pumping’) of air below convective cloud cells. In another case, a diel variation of DMS was observed in the ML. Our data suggest that meteorological rather than photochemical processes were responsible for this behavior. Based on model calculations we estimate a DMS lifetime in the ML of 0.9 days and a DMS sea-to-air flux of 2–3 μmol m−2 d−1. These estimates pertain to early austral summer conditions and southern mid-ocean latitudes. Typical MSA concentrations were 11 ppt in the ML and 4.7–6.8 ppt in the FT. Sulfur-dioxide values were almost constant in the ML and the lower FT within a range of 4–22 ppt between individual flight days. A strong increase of the SO2 concentration in the middle FT (5.3 km) was observed. We estimate the residence time of SO2 in the ML to be about 1 day. Aqueous-phase oxidation in clouds is probably the major removal process for SO2. The corresponding removal rate is estimated to be a factor of 3 larger than the rate of homogeneous oxidation of SO2 by OH. Model calculations suggest that roughly two-thirds of DMS in the ML are converted to SO2 and one-third to MSA. On the other hand, MSA/nss-SO42- mole ratios were significantly higher compared to values previously reported for other ocean areas suggesting a relatively higher production of MSA from DMS oxidation over the Southern Ocean. Nss-SO42- profiles were mostly parallel to those of MSA, except when air was advected partially from continental areas (Africa, Australia). In contrast to SO2, nss-SO42- values decreased significantly in the middle FT. NH4+/nss-SO42- mole ratios indicate that most non-sea-salt sulfate particles in the ML were neutralized by ammonium.

Ethical beliefs' differences of males and females

Abstract: This study investigates the differences in ethical beliefs between males and females. One hundred and seventy five business students were presented with four scenarios and given the Reidenbach-Robin instrument measuring their ethical reactions to these scenarios. Contrary to previous research, the results indicate that the two groups have similar ethical beliefs, and they process ethical information similarly.

On the choice of functional form for hedonic price functions

Abstract: The empirical results presented in this paper demonstrate the usefulness of quadriatic models in the estimation of hedonic price functions We propose a quadriatic semi-log model, a restricted case of the quadriatic Box-Cox model, whose standardized marginal attribute prices are linear functions of the attribute vector This specification outperforms the linear Box-Cox specification in terms of explanatory power, and captures much of the increase in explanatory power provided by the quadriatic Box-Cox model without the corresponding loss in the ability to interpret the coefficient estimates For policy applications, the quadriatic Semi-log model provides a useful alternative to linear specification

Integrative goals for instructional design

Abstract: Finding considerable agreement in their previous writings regarding the singular types of learning outcomes, the authors affirm a need to identify learning goals that require an integration of multiple objectives. The occurrence of multiple objectives is frequently encountered when instruction must reach beyond the individual topic or single lesson to the module, section, or course. It is proposed that such integration of objectives be conceived in terms of the pursuit of a comprehensive purpose in which the learner is engaged, called anenterprise. Given such an integrative goal of performance resulting from instruction, the various single objectives are viewed as being integrated as constituents of anenterprise schema. Three varieties of enterprise and their associated enterprise schemas are described, designated by their goals asdenoting, manifesting, anddiscovering. It is suggested that instructional design procedures include provisions for the learning of enterprise schemas when the integration of multiple objectives is required. Such schemas are also seen as playing a facilitating role in transfer of training.

Intrinsic states of deformed odd-A nuclei in the mass regions (151 221)

Abstract: A review of the empirical data on intrinsic states of odd-$A$ nuclei in the mass range $151\ensuremath{\le}A\ensuremath{\le}193$ and $A\ensuremath{\ge}221$ is presented. Global summaries of the data are presented in tables for each isotopic and isotonic chain, wherein the excitation energy, the $log\mathrm{ft}$ values, the moment-of-inertia parameter, and the decoupling parameter (for $K=\frac{1}{2}$ bands) are listed for single-particle, vibrational admixed, and pure vibrational states. Similar data are separately presented for three-quasiparticle excitations in the rare-earth region. Taking guidance from the systematics on nuclear deformation, the single-particle deformed potential for axially symmetric and reflection-symmetric shapes (the Nilsson model) modified by the hexadecapole deformation is used to interpret the data. Other variations of the Nilsson model, which include axially asymmetric shapes ($\ensuremath{\gamma}$ deformation) and especially reflection-asymmetric shapes (octupole deformation), have also been used to interpret the data in certain limited regions. Systematics for the intrinsic excitations are presented and discussed in terms of these models. The newly emerging regions of the octupole-quadrupole deformation and superdeformation are also discussed.