Isomorphic Behavior Research Articles

Percepções de pesquisadores sobre atividades cooperativas de P&D: uma análise com base na teoria institucional

Estudo visando captar as percepções de pesquisadores de Minas Gerais, experientes em pesquisa cooperativa, quanto a: i) motivação para parcerias em P&D; ii) dinâmica e estabilidade de alianças; iii) consecução de objetivos fixados para as atividades compartilhadas. Foram analisadas 47 questões, definidas a partir de literatura sobre redes organizacionais e sobre redes cooperativas de pesquisa, respondidas por 305 pesquisadores, de um público-alvo de 673 cientistas. Aplicou-se o método de Analise Fatorial às questões, que então gerou 11 fatores, que se agruparam nas dimensões Criação de Redes, Operação e Resultados. A aplicação da Teoria Institucional revelou alto isomorfismo na percepção dos pesquisadores quanto aos conteúdos das questões, fato revelado pelas técnicas estatísticas empregadas. Foram identificadas pressões coercitivas exercidas pelas Agências de Fomento à Pesquisa, que parecem cultivar mitos racionalizados relativos à eficiência das atividades cooperativas. Aspectos diversos levantados na investigação indicam que o mecanismo de redes cooperativas, para o desenvolvimento das atividades de P&D, se encontra, no Brasil, em fase de pré-institucionalização.

Economic rents and legitimacy: incorporating elements of organizational analysis institutional theory to the field of business strategy

Are sources of economic rent, as defined by the prevalent business strategy paradigm, sufficient to attain and maintain superior returns? The perspective developed within the conceptual framework of the Institutional Theory may offer managers a contribution towards understanding the strategy process and its potentialities, particularly by stressing the leading role played by legitimacy, the influence of many institutional spheres, the isomorphic pressures, ceremonial behavior and decoupling, among other elements, that mainstream business strategy fails to address directly, but which may have a significant effect on firm performance. We advance that these elements must be accounted for in the pursuit and acquisition of economic rents, even if the ability to articulate them purposefully is constrained by rationality, agency conditions and the manager's social embeddedness.

Economic rents and legitimacy: incorporating elements of organizational analysis institutional theory to the field of business strategy

Are sources of economic rent, as defined by the prevalent business strategy paradigm, sufficient to attain and maintain superior returns? The perspective developed within the conceptual framework of the Institutional Theory may offer managers a contribution towards understanding the strategy process and its potentialities, particularly by stressing the leading role played by legitimacy, the influence of many institutional spheres, the isomorphic pressures, ceremonial behavior and decoupling, among other elements, that mainstream business strategy fails to address directly, but which may have a significant effect on firm performance. We advance that these elements must be accounted for in the pursuit and acquisition of economic rents, even if the ability to articulate them purposefully is constrained by rationality, agency conditions and the manager's social embeddedness.

The Verification and Control of Interacting Similar Discrete-Event Systems

This paper explore issues related to the control and verification of similar module systems in the discrete-event systems framework. Similar module systems are distributed systems comprised of subsystem modules that exhibit isomorphic local behavior coordinated on global event occurrences. When given a global model of these systems, it is shown how to decompose the global model into the component subsystems in polynomial time. It is also shown how to perform various verification tasks for these interacting systems while mitigating common state explosion difficulties by taking advantage of the special similar module system structure. Control properties of the similar module systems are also discussed. It is assumed that the local modules are supervised by exactly one local controller and the controllers enforce the same local control policy. Necessary and sufficient conditions for achieving local and global control specifications in this setting are identified.

Closed Solubility Loops in Liquid Mixtures

Abstract Based on the principle of isomorphic critical behavior of fluid mixtures we derive a simple equation for closed solubility loops in a temperature–concentration diagram at constant pressure. The validity of the simple equation is tested by comparisons with experimental solubility data for liquid mixtures at atmospheric pressure and at elevated pressures. We also elucidate the nature of liquid–liquid phase separation in the vicinity of a double critical point. Specifically, we show how from an expansion around the critical double point one can develop a description of solubility loops as a function of pressure.

How to turn a second-order cellular automaton into a lattice gas: a new inversion scheme

In second-order cellular automata, the signals made available to the local transition function include, besides the current state of a site's neighbors, also the previous state of the site itself. Some similarities had been noted, especially in physics simulations, between certain second-order cellular automata and certain lattice gases. Here we show how to construct, for any second-order cellular automaton, a lattice gas having isomorphic functional behavior. (Paradoxically, this isomorphism of function is achieved by compromising on the isomorphism of structure: namely, the group of translation symmetries of the resulting lattice gas is coarser than that of the original cellular automaton.) The advantage of our construction is that, while invertibility in cellular automata is not directly deducible from the local map (indeed, it is in general undecidable), in the second-order case the invertibility of the cellular automaton goes hand-in-hand with that of the corresponding lattice gas—and for lattices gases invertibility is trivially decidable on the basis of the local structure. From a physical viewpoint, our construction illustrates a trade-off between two ways of achieving a “force” of a given range. In a cellular automaton, multiple copies of a signal are made and distributed in parallel to several sites, explicitly providing the desired fanout width. In a lattice gas, with our construction, one can let a single signal serially service a number of sites along an appropriate spacetime route. The latter method is better suited to a nondissipative implementation of the dynamics.

Critical behavior of dielectric permittivity and electric conductivity in temperature and pressure studies above and below the critical consolute point

Results of comprehensive temperature (T) and pressure (P) studies of static dielectric permittivity (ε′) and electric conductivity (σ) in the one- and two-phase regions of critical nitrobenzene–dodecane mixture are presented. A strong asymmetry of determined coexistence curves causes a strong violation of the law of rectilinear diameter. The obtained critical anomalies in the homogeneous phase [εhomo′(T),εhomo′(P),σhomo(P)] or the diameter of the binodal [εmean′(T),εmean′(P),σmean(T),σmean(P)] are associated with the same critical exponent φ=1−α ≈0.88, where α is the specific heat critical exponent. Critical anomalies for the isothermal, pressure path exhibit a set of favorite in comparison with results obtained in σ(T) and ε(T) tests. They are: the negligible influence of the critical Maxwell–Wagner effect, the hardly visible appearance of the correction-to-scaling term, a more pronounced manifestation of critical anomalies, and a reduced number of fitted parameters. Particularly noteworthy is the evidence for the σhomo(P) anomaly in the homogeneous phase, hardly obtained up to now in a mixture of a low electric conductivity. Results presented suggest the isomorphic behavior of ε′(T), σ(T) and ε′(P), σ(P) critical anomalies for the homogeneous phase and for the diameter of the binodal.

Molecular Dynamics Simulation Study of DNA Triplex Formed by Mixed Sequences in Solution

The unrestrained molecular dynamics simulation of the triple helical DNA with mix sequences d(GACTGGTGAC)•d(CTGACCACTG)*d (GACTGGTGAC), using the particle mesh Ewald sum, is presented here. The Ewald summation method effectively eliminates the usual “cut-off” of the long—range interactions and allowed us to evaluate the full effect of the electrostatic forces. The AMBER5.0 force field has been used during the simulation in solvent. The MD results support a dynamically stable model of DNA triplex over the entire length of the trajectory. The duplex structure assumes the conformation, which is very close to B-DNA. In mixed sequences the purine bases occurs in both strand of DNA duplex. The bases of third strand do not favor the Hoogsteen or/and reverse Hoogsteen type of Hydrogen bonding but they form hydrogen bonds with the bases of both the strand of DNA duplex. The orientation of the third strand is parallel to one of the strand of duplex and all nucleotides (C, A, G & T) show isomorphic behavior with respect to the DNA duplex. The conformation of all the three strands is almost same except few exceptions. Due to interaction of third strand the conformational change in the duplex structure and a finite amount of displacement in the W-C base pairs have been observed. The conformational variation of the back bone torsion angles and helicoidal parameters, groove widths have been discussed. The sequence—dependent effects on local conformation, helicoidal and morphological structure, width of the grooves of DNA helix may have important implication for understanding the functional energetics and specificity of interactions of DNA and its triplexes with proteins, pharmaceutical agents and other legends.

Intra- and Inter-organizational Imitative Behavior: Institutional Influences on Japanese Firms' Entry Mode Choice

This paper compares the predictions of transaction cost and institutional theories in an empirical study of the entry mode choice for 1,194 Japanese foreign subsidiaries. The findings indicate the institutional model adds significant explanatory power over and above the predictions of the transaction cost model. Using the concepts of frequency-based, trait-based and outcome-based imitation, I find support for institutional isomorphism, as later entrants tended to follow the entry mode patterns established by earlier entrants. Isomorphic behavior was also present within a firm, as firms exhibited consistency in entry mode choices across time. Further, a firm's investment experience moderated institutional influences on entry mode choice.

Isomorphic behavior of random copolymers: thermodynamic analysis of cocrystallization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

A theory of the thermodynamics of comonomer cocrystallization in copolymers is developed. This theory is applicable to cocrystallization over a wide range of comonomer composition and thus provides the phase diagrams for copolymers showing isomorphism in a strict sense and isodimorphism. Experimental data about the melting of the P(3HB-3HV) copolymers are analyzed. The melting point vs composition curve of these copolymers is consistent with the proposed diagram for an isodimorphic copolymer system

Isomorphic behavior of poly(aryl ether ketone) blends

AbstractBlends of various poly(aryl ether ketones) have been found to exhibit a range of miscibility and isomorphic behavior. This range is dependent on molecular weight; however, for poly(aryl ether ketones) with number‐average molecular weight of 20,000, this range is about ±25% difference in ketone content. All miscible blends exhibit isomorphism, and all immiscible blends exhibit no evidence of isomorphism. The dependence of the glass transition temperature Tg versus composition exhibits a minimum deviation from linearity whereas the melting temperature Tm versus composition exhibits a pronounced maximum deviation from linear behavior.The crystalline melting point versus composition for isomorphic blends is considerably different than for random copolymers with isomorphic units. Homopolymers and random copolymers exhibit a melting point that is a linear function of ketone content (increasing ketone content increases Tm). For blends, the melting point is essentially the same as that of the higher melting constituent until high levels of the lower melting constituent are present. The observed melting point versus composition behavior will be interpreted using classical theory to calculate the components of the liquid and crystalline phase compositions. As a miscible blend is cooled from the melt, essentially pure component of the highest melting point crystallizes out of solution, as predicted by calculated solid‐liquid phase diagrams. This occurs until the crystallization is complete owing to spherulitic impingement. At high concentrations of the lower melting constituent, lower melting points will be observed because the highest melting constituent will be depleted before the crystallization is complete.In many miscible blends involving addition of an amorphous polymer to a crystalline polymer, the degree of crystallinity of the crystalline polymer has been shown to increase. On the basis of evidence presented here, it is hypothesized that dilution by a miscible, amorphous polymer allows for a higher level of crystallinity.

Gonadal hormone specificity in the sexual behavior of ring doves

1. Specific effects of gonadal hormones on male and female sexual behavior in ring doves ( Streptopelia risoria) were studied as follows: Reproductively experienced male and female ring doves were castrated and (a) treated with testosterone proprionate (TP; ranging 200–800 μg) then tested with responsive females or (b) treated with estradiol benzoate (EB, ranging 50–200 μg) and tested with active males for sexual behavior. 2. The main findings were: (1) Male specific behavior patterns, such as bow-cooing and hop-charging are readily induced by TP but not by EB; conversely female specific behavior patterns, such as sexual squatting are readily induced in both sexes by EB but not by TP. (ii) Isomorphic behavior pattern, such as wingflipping and nest-soliciting are more easily induced by TP than EB in males, and EB than TP in females. 3. The results are interpreted in support of hormone specific effects and discussed in conjunction with relevant data on rats.

Stereochemical Correspondence among Chemically Disparate Systems: Spirocyclic Phosphoranes, Diarylmethanes, and Cognates

Certain chemical systems which differ greatly in many of their chemical properties may nevertheless exhibit stereochemically isomorphic behavior, i.e., they may be stereochemically correspondent. Two such systems are spirocyclic pentacoordinate molecules and molecules of the type Ar(2)ZX. The consequences of stereochemical correspondence between these two systems are explored in depth.

Isomorphous replacement in a copolyamide system

AbstractIn a study of isomorphic behavior, it was found that the melting point—composition curve of the copolyamides prepared from caprolactam and p‐aminomethylcyclohexylcarboxylic acid was sigmoidal, indicating that the methylcyclohexyl group was interchangeable in the crystal lattice with aliphatic carbon atoms of ω‐aminocaproic acid. On the other hand, the benzyl group in the copolymers of caprolactam and p‐aminomethylbenzoic acid did not interchange as well, and only partial isomorphism occurred. The analogous meta derivatives, m‐aminomethylcyclohexylcarboxylic acid and m‐aminomethylbenzoic acid, did not fulfill the spatial requirements of caprolactam. Although V‐shaped melting point—composition curves resulted, the disturbance in the crystal network was more severe with the m‐phenyl derivative than with the m‐cyclohexyl derivative.

Isomorphic Relationship between Rubidium and Thallium in Igneous Minerals

V. M. GOLDSCHMIDT1 has been able to demonstrate that the radius of an ion is a fundamental factor in regulating isomorphic behaviour, ions of like size being capable of replacing each other isomorphically within a crystal lattice. The application of this law of crystal chemistry to a study of the distribution of the elements in the earth's crust has yielded fruitful results; in particular, the behaviour of many of the rarer elements during the fractional crystallization of a magma is now reasonably well understood. For example, Goldschmidt2 has pointed out that, since the radii of Rb+, Tl+ and Cs+ (1·49, 1·49 and 1·65 A., respectively) are similar to that of K+ (1·33 A.), these elements are commonly found in potassium-rich minerals, particularly those of late pegmatitic phases.