APC intragenic haplotypes in familial adenomatous polyposis

Genetic epidemiological studies are useful for the knowledge of the association of markers and genes involved in diseases. In the present work, we studied the frequency of four adenomatous polyposis coli intragenic RFLP markers often used in risk evaluation in a population of 10 familial adenomatous polyposis patients from 10 unrelated Portuguese familial adenomatous polyposis families not sharing the same mutation, and in a population of 55 unrelated healthy Portuguese volunteers. We compared the frequency obtained to normal and affected populations and to results already reported in other populations. We observed allelic frequencies for the Portuguese population that agree with the published ones. The intragenic polymorphisms show strong gametic disequilibrium suggesting little recombination between them. We observed haplotype frequencies significantly different in patients and controls. The gametic disequilibrium may be due to a common founder for a proportion of apparently unrelated probands.     

A naturalistic study of children's social understanding.

Examined developmental aspects of social understanding in 3 related contexts: a one-to-one interview, a real-life activity group, and related group discussions. 24 2nd, 3rd, 4th, and 5th graders, homogeneous with respect to level of reflective social understanding (as expressed in the interview), were assigned to each of 4 small activity groups. Each group met for 12 consecutive school weeks in adult-supervised after-school cooperative group activities and discussions about group functioning. Discussions from each group meeting were coded for instances of verbally expressed communicative competencies. Results suggest a relation between level of social understanding, reflectively expressed, and frequency of competent communications expressed in the course of the group discussions. Ss' strategies for task-related negotiations were also coded. The number of developmentally advanced strategies was significantly lower for the group of young Ss with low-level reflective social understanding as compared to the other 3 groups. Results are discussed in the context of problems associated with assessing developmental levels of social understanding in natural settings. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the Fast and Rigorous Analysis of Compensated Waveguide Junctions Using Off-Centered Partial-Height Metallic Posts

In this paper, we present an efficient and rigorous method, based on the 3-D boundary integral-resonant-mode expansion technique, for the analysis of multiport rectangular waveguide junctions compensated with partial-height cylindrical metallic posts. The electrical performance of a great variety of commonly used wideband microwave circuits has been improved drastically thanks to the introduction of a new design parameter, i.e., the relative position of the metallic post in the structure. To the authors' knowledge, this parameter has not been taken into account in previous studies concerning compensated junctions using partial-height metallic posts. The developed tool has been successfully used to design compensated H- and E-plane right-angled bends and power dividers, as well as optimal magic-T junctions. This novel tool has been fully verified through comparisons between our results and those provided by a well-known commercial finite-element method software     

Comparison study of lewis acid type catalysts on the esterification of octanoic acid and n-octyl alcohol

A Comparative study of different Lewis acids (metal chlorides of valences, I, II, III, IV) has been made. These catalysts are used in the synthesis of a high molecular weight ester in a stirred tank reactor using octanoic acid and n-octyl alcohol as reactants. It was found that the best efficiency of the formatted ester (n-octyl octanoate) was obtained with ferric chloride. This could be explained by the high electronegativity and the existence of free d orbitals in the Lewis acid.     

From physical to standard time

In the last few years, a variety of contributions have come to alleviate the shortage of studies concerning the relationship between time and knowledge, though none of them uses a standard language of temporal logic. In contrast, our approach consists of formalizing a representational system based on a discrete temporal logic which boundlessly branches off both to the left and to the right. This system will allow us to refer to standard time, to define temporal distances between pairs of instants, and to express temporal properties of constant or periodic events by means of continuous or discontinuous intervals. the organization of this article is as follows. First, we will define the semantics of a temporal logic which summarizes the ontology of time from our point of view—that of Physicae Logica—as well as its operators. Subsequently, we will justify the convenience of establishing a relativistic calculus between its intervals. We will next analyze the effect of giving our logic a quantitative, rather than a qualitative orientation. Finally, we will explain the transition from a quantified Physicae Logica to a Physicae Logica with standard time. © 1995 John Wiley & Sons, Inc.     

A data model for processes based on relative time

Advanced database applications such as automated manufacturing, scheduling, and computer-aided software engineering, demand an explicit representation of processes, including their decomposition into subprocesses, where subprocesses may be repeated or shared. Temporal information on these processes is inherently relative to particular temporal frames of reference, that may be different from that of a complex process containing them. We suggest the Rtime object-oriented data model in which processes are first-class citizens and complex processes are built, using standard type constructors, from their component processes. The relative timing of component processes is a key feature of the suggested model. It allows for a modular construction of complex process objects that may be repeated and shared. Standard object-oriented query languages can be used for temporal queries on processes, by providing an operator for translating timing information between different temporal frames of reference.     

Use of the hybrid TEM-dual surface wave in coaxial cables and resonators to reduce attenuation

Experimental evidence is given of the reality of this hybrid wave in a coaxial guide having supporting surfaces of deliberately enhanced reactance. Moreover it is shown that a very significant reduction in attenuation is obtainable by this technique.     

Production of pure phosphoric acid from El-Sebaeya low-grade phosphate ore

The extraction of phosphoric acid by tributyl phosphate (TBP) in kerosene from hydrochloric acid leach liquor of El-Sebaeya low-grade phosphate ore was carried out. The influence of various factors affecting the leaching process such as particle size, reaction time, acid concentration, liquid/solid mass ratio, reaction temperature and stirring speed were thoroughly studied to estimate the favor phosphate ore dissolution in relation to impurity. Thereafter, the effects controlling the extraction step, including shaking time, solvent concentration, aqueous/organic phase ratio, and reaction temperature, have been studied in terms of the maximum P₂O₅ extraction efficiency and the minimum impurities extraction efficiency. The obtained loaded organic solvent was subjected to the stripping stage using double-distilled water. The outlet stripping liquor was concentrated by evaporation up to 62% P₂O₅.     

Determinants of Enterprise System Adoption Across the System Lifecycle: Exploring the Role of Economic Development

The authors studied enterprise systems adoption in transition and less-developed economies within the European Union in search of determinants (critical success factors and barriers) across the system lifecycle. They found 14 determinants drawing from interviews with practitioners whose experience exceeds 280 projects. The authors compared their data with prior results from well-developed countries and concluded that determinants and their criticality across the lifecycle depend on the level of economic development. The authors discussed implications and provided recommendations.