Strategic Deterrence Among Multipoint Competitors

Theory and methods from organizational ecology and the strategyfield are combined to predict the dynamic consequences of strategicdeterrence. A model is developed to investigate which strategieswill prevail through an industry ‘shake out’ whensome firms compete while others forbear from competing withtheir ‘multipoint’ rivals—those faced in morethan one markes or market segment. Theory predicts that multipointcontact affects competition within but not between strategicgroups, and it is speculated that whether multipoint contactdeters competition depends on strategic objectives. The predictionsare supported by estimates of market exit rates in the customerpremises equipment and service (CPES) sector of the deregulatedAmerican telephone industry. The results show that, due to forbearance,weak competitors can out-survive strong competitors. Evidencealso is found that strategic groups not protected by mobilitybarriers face strong competition from other strategic groups.Implications for the study of strategic evolution are discussed.     

TWENTIETH CENTURy URBAN REGIMES

There have been important continuities in the political character of American cities over the course of the twentieth century. Cities have also varied in the manner in which their politics have been organized. A useful vehicle for understanding both continuities and variations in city politics is the concept of an urban regime. A variety of regimes can be distinguished which enable us to interpret the course of urban politics in the twentieth century and to connect its essential features to the larger political economy.     

Enumeration of Fluorescent Pseudomonads on Poultry by using the Hydrophobic-Grid Membrane Filter Method

Accurate enumeration of fluorescent pseudomonads on poultry was possible by using hydrophobic-grid membrane filters and S-I agar. In methionine-cysteine broth, fluorescent isolates produced more volatile sulfides and yielded higher odor scores than nonfluorescent isolates. Fluorescent pigment had an inhibitory effect on the growth of nonfluorescent isolates. Resuscitation on Trypticase Soy Agar resulted in a significant increase in the recovery of fluorescent pseudomonads. Shelf life was negatively correlated (r = -0.86) with initial numbers of fluorescent pseudomonads.     

Pore Evolution During Glow Discharge Sintering of Alumina

A series of experiments have been performed to demonstrate the applicability of small-angle neutron scattering to the study of pore evolution during sintering. Samples of α-Al₂O₃ which had been zone sintered in a hydrogen hollow cathode glow discharge to densities exceeding 94% of theoretical were employed in these preliminary measurements. The neutron scattering results indicate that densification during the final stages of glow discharge sintering occurs primarily through a reduction in the number of pores present with only a small change in the average pore size.     

Tracing Recurrent Activity in Cognitive Elements (TRACE): a Model of Temporal Dynamics in a Cell Assembly

Hebb's introduction of the cell assembly concept marks the beginning of modern connectionism, yet its implications remain largely unexplored and its potential unexploited. Lately, however, promising efforts have been made to utilize recurrent connections, suggesting the timeliness of a re-examination of the cell assembly as a key element in a cognitive connectionism. Our approach emphasizes the psychological functions of activity in a cell assembly. This provides an opportunity to explore the dynamic behavior of the cell assembly considered as a continuous system, an important topic that we feel has not been given sufficient attention. A step-by-step analysis leads to an identification of characteristic temporal patterns and of necessary control systems. Each step of this analysis leads to a corresponding building block in a set of emerging equations. A series of experiments is then described that explore the implications of the theoretically derived equations in term of the time course of activity generated by a simulation under different conditions. Finally, the model is evaluated in terms of whether the various constraints deemed appropriate can be met, whether the resulting solution is robust, and whether the solution promises sufficient utility and generality.     

Low Dose Irradiation Influence on Yield and Quality of Fruit Juice

Granny Smith apples, Valencia oranges, and Pearlette grapes grown in Queensland, Australia were irradiated at 0, 75, 300 and 600 Gy. Following irradiation, juice was extracted and analysed for quality and compositional changes. Irradiation treatment significantly (p<0.05) decreased yield of apple juice (by 6.3% w/w at 600 Gy) and grape juice (by 4.8% w/w at 600 Gy) but did not significantly (p>0.05) affect yield of orange juice (OJ). Acceptability significantly (p<0.05) decreased in OJ after 600 Gy treatment. Other changes in quality and composition were minimal. Juice from irradiated apples and oranges stored at 5°C for 8 wk showed similar results.     

DAMINOZIDE RESIDUE PRESENT IN APPLE FRUIT AFTER LONG AND SHORT TERM EXPOSURE

Daminozide residues were determined in ppm or ppb on 'Starking', 'Red King', 'Rome'and 'Golden Delicious'apples after repeated long term exposure (21 years) and on 'Top Red'apples after short term (1 year) exposure. Application rates varied from 2.2 to 9.0 kg/ha for short term exposure and 2.2 to 4.5 kg/ha for long term exposure. Two and three years after cessation of the daminozide spray program no daminozide residues were found in 'Top Red'regardless of the rate applied or analytical procedure used. Daminozide residues (<1 ppm) were present in 'Starking', 'Red King', 'Rome'and 'Golden Delicious'one year after cessation of the spray program. The cultivar 'Rome'had consistently higher daminozide residue levels followed by 'Golden Delicious', 'Red King'and 'Starking'.     

Isolation and Identification of Objectionable Volatile Flavor Compounds in Defatted Soybean Flour

The volatile flavor constituents of defatted soy flour were isolated by a specially designed apparatus. The isolated volatiles were fractionated by gas chromatography. The fractions with characteristic beany, grassy, and green odors were identified by infrared and mass spectrometry. A total of 25 compounds was identified, including nine alcohols, six aldehydes, nine ketones, and 2-pentyl furan. Among the identified compounds, 2-pentyl furan and ethyl vinyl ketone are probably the key compounds for the beany and grassy odors of the soy flour. All the compounds identified in this study can be postulated as autoxidative decomposition products of soy lipids. Therefore, the presence of these compounds in soy flour might be due to the incomplete removal of lipids in soy flour.     

Characterization of the Nonvolatile Minor Constituents Responsible for the Objectionable Taste of Defatted Soybean Flour

A scheme was developed for the separation of the nonvolatile minor constituents from soy flour which are responsible for the astringent an bitter tastes. The scheme involved solvent extraction, freeze drying, and fractional crystallization. Two fractions, collected by semipreparative HPLC, had the characteristic bitter and astringent tastes. Further fractionation by reverse phase HPLC produced three pure compounds which were identified by UV, NMR spectrometry and elemental analysis, as daidzein, glycitein 7-β-O glucoside, and genestin. Preliminary sensory evaluation showed that these isoflavones might contribute additively to the undesirable bitter and astringent tastes of soy protein products.     

The generation and interpretation of false-colour composite principal component images

The presentation of multichannel image information in terms of a false-colour composite can, in general, be achieved with less sacrifice of data if the three leading principal component images are used rather than the three conventional raw channels

A hardwired electronic system which has been developed is described in outline; it implements principal components analysis on 256 x 256 four-channel array of pixels in a few seconds. The system is under the control of an APPLE II microcomputer, and can generate colour hard-copy output in the form of composites of the principal component images

The use of this system is illustrated by reference to a LANDSAT MSS subframe of southern Spain. A standard false-colour composite of this scene contains 73 per cent of the available image variance whereas the principal component composite contains 98 per cent. The necessity of contrast stretching the minor principal component images in order to generate a visually effective colour composite is demonstrated. Some consideration is given to the choice of the most appropriate colour coding in the principal component composite images.