The metamathematics of Fraïssé's order type conjecture

Author(s):  
P. Clote
Keyword(s):  
1987 ◽  
Author(s):  
Moideen P Jamaluddin

Platelet aggregation kinetics, according to the particle collision theory, generally assumed to apply, ought to conform to a second order type of rate law. But published data on the time-course of ADP-induced single platelet recruitment into aggregates were found not to do so and to lead to abnormal second order rate constants much larger than even their theoretical upper bounds. The data were, instead, found to fit a first order type of rate law rather well with rate constants in the range of 0.04 - 0.27 s-1. These results were confirmed in our laboratory employing gelfiltered calf platelets. Thus a mechanism much more complex than hithertofore recognized, is operative. The following kinetic scheme was formulated on the basis of information gleaned from the literature.where P is the nonaggregable, discoid platelet, A the agonist, P* an aggregable platelet form with membranous protrusions, and P** another aggregable platelet form with pseudopods. Taking into account the relative magnitudes of the k*s and assuming aggregation to be driven by hydrophobic interaction between complementary surfaces of P* and P** species, a rate equation was derived for aggregation. The kinetic scheme and the rate equation could account for the apparent first order rate law and other empirical observations in the literature.


1977 ◽  
Vol 42 (2) ◽  
pp. 199-209 ◽  
Author(s):  
Betty Z. Liles ◽  
Martin D. Shulman ◽  
Susan Bartlett

Fifteen linguistically normal children and 15 linguistically deviant children were presented with three types of agrammatical sentences. The subjects were asked to judge the sentences as right or wrong and to change the sentences judged as wrong, rendering them correct. The three types of agrammatical sentences represented rule violations of syntactic agreement (Type A), lexical restrictions (Type B), and word order (Type C). The two groups of children were compared in terms of the number of sentences of each type that were recognized as agrammatical. Those productions which represented the child’s correction of agrammatical sentences were subjected to descriptive analyses (percentages) with specific reference to the number of attempted changes and the number of those changes which demonstrated corrections of the specific deviation from well formedness. Results indicated that the two groups of subjects were significantly different in their ability to recognize grammatical errors in sentence Types A and C, but did not differ in their ability to recognize errors in sentence Type B. The descriptive comparison of the groups' verbal corrections reflected this trend, in that the language-disordered subjects made corrections specific to the error on more of the Type B sentences (for example, “The dog writes the food.”) than on Types A (for example, “'She will pick some flowers last week.”) or C (for example, “Get and come your dinner.”). Linguistically normal children accurately corrected 90.7% of the sentences judged as agrammatical; this percentage did not vary more than 1% across sentence types.


10.37236/408 ◽  
2010 ◽  
Vol 17 (1) ◽  
Author(s):  
David Eppstein

We define the limiting density of a minor-closed family of simple graphs $\mathcal{F}$ to be the smallest number $k$ such that every $n$-vertex graph in $\mathcal{F}$ has at most $kn(1+o(1))$ edges, and we investigate the set of numbers that can be limiting densities. This set of numbers is countable, well-ordered, and closed; its order type is at least $\omega^\omega$. It is the closure of the set of densities of density-minimal graphs, graphs for which no minor has a greater ratio of edges to vertices. By analyzing density-minimal graphs of low densities, we find all limiting densities up to the first two cluster points of the set of limiting densities, $1$ and $3/2$. For multigraphs, the only possible limiting densities are the integers and the superparticular ratios $i/(i+1)$.


2019 ◽  
Vol 305 ◽  
pp. 169-182 ◽  
Author(s):  
Kitti Gelle ◽  
Szabolcs Iván
Keyword(s):  

Retos ◽  
2016 ◽  
pp. 20-25 ◽  
Author(s):  
Antonio Méndez-Giménez ◽  
Diego Martínez de Ojeda Pérez ◽  
Juan José Valverde-Pérez

 En la actualidad, el modelo de Educación Deportiva destaca entre los enfoques de enseñanza centrados en el alumnado y con mayor impacto en los profesionales de la educación física. Los beneficios de su hibridación con el enfoque basado en la autoconstrucción de materiales no han sido aún explorados ni de manera longitudinal ni en Educación Primaria. El objetivo fue conocer y comparar la valoración de los docentes y su alumnado del uso de dos tipos de material (convencional y autoconstruido) durante dos temporadas consecutivas de Educación Deportiva. Participaron un total de 51 estudiantes de 3º y 4º de educación primaria y sus dos maestros de educación física. Se realizó un diseño cruzado simple cuasi-experimental de grupos aleatorios y muestreo no probabilístico por conveniencia, en el que los dos niveles de la variable independiente (material convencional y autoconstruido) se aplicaron a los dos cursos participantes. Para la recogida de datos se utilizaron los diarios del docente así como entrevistas grupales a los estudiantes y entrevistas individuales a los docentes, antes y después de la implementación de cada unidad didáctica: ultimate e indiacas. Los datos fueron analizados por medio de comparaciones constantes. Los resultados indican un alto entusiasmo del alumnado durante ambas unidades, aunque muestran una inercia metodológica favorable al material autoconstruido según el orden del tipo de material utilizado. Además, se encontró que el material autoconstruido fomenta la actividad física extraescolar. Futuras investigaciones deberán analizar el nivel de actividad física en la educación física y en el período extraescolar dependiendo del material utilizado.Abstract. Currently, the Sport Education model stands out among the teaching approaches centered on the students and having a higher impact on the Physical Education teachers. The benefits of the hybridization based on self-made materials have not been studied either longitudinally or in Primary Education. The objective was to know and to compare the assessment of teachers and their students regarding the use of two types of materials (conventional and self-made) during two consecutive Sport Education seasons. A total of 51 students enrolled in grades 3 and 4 of Primary Education and their two Physical Education teachers took part in the experience. We used a quasi-experimental simple crossover design with randomized groups and non-probabilistic convenience sampling, in which the two levels of the independent variable (conventional and self-made materials) were applied in the two grade levels participating in the study. Data were collected by means of teacher diaries, group interviews with the students and individual interviews with the teachers, before and after implementation of each of the following didactic units: «ultimate» and «indiacas». Data collection was performed using constant comparisons. The results showed a high level of students’ enthusiasm during both didactic units, although the data analyzed indicated a methodological inertia to the self-made material, according to the order type of the used material. Besides, it was found that the self-made material encourages participation in extracurricular physical activities. Further studies are required to analyze physical activity levels in and outside the Physical Education setting as a function of the material used.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Taslima Akther ◽  
Fengju Xu

Purpose This study aims to investigate the factors that enhance the credibility of and confidence in audit value. Design/methodology/approach Data were collected from 254 institutional investors through a questionnaire survey and were analyzed using partial least squares structural equation modelling (PLS-SEM). Findings The findings reveal that the two influential predictors of enhanced credibility and confidence are perceived auditor independence and improved auditor communication. Factors related to auditor–client affiliation, such as restrictions on providing non-audit services, mandatory auditor rotation and the presence of effective audit committees, are identified as creating the perceived independence. Improved auditor communication is linked with improving the audit report and ensuring audit education, thus creating more sophisticated users who better understand the scope and purpose of an audit. Furthermore, independent audit oversight acts as a moderator in the relationship between perceived auditor independence, improved auditor communication and enhanced credibility. Enhanced credibility can lead to greater confidence in audit value. Originality/value In the wake of the global financial crisis and loss of confidence in the role of auditors, this study investigates the factors that can enhance the credibility of and confidence in audit value, especially in a non-Anglo-American setting. This study is unique in terms of methodological development, as it uses a higher-order Type II reflective–formative model using PLS-SEM.


2004 ◽  
Vol 28 (7) ◽  
pp. 1711-1743 ◽  
Author(s):  
John W. Cooney ◽  
Richard W. Sias
Keyword(s):  

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