Changes in adolescents' daily interactions with their families from ages 10 to 18: Disengagement and transformation.

In a cross-sequential study spanning 5th-12th grade, 220 White working-and middle-class youth provided reports on their experience at 16,477 random moments in their lives. Amount of time spent with family was found to decrease from 35% to 14% of waking hours across this age period, indicating disengagement. However, transformation and continued connection were evident in stability across age in time talking and alone with parents; an age increase in family conversation about interpersonal issues, particularly for girls; and with age, adolescents' more frequent perception of themselves as leading interactions. After a decrease in early adolescence, older teens reported more favorable affect in themselves and others during family interactions. Last, the age decline in family time was found to be mediated not by internal family conflict but by opportunities and pulls an adolescent experiences from outside the family. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A study of techniques for reducing ash deposition in coal-fired gas turbines

Direct coal-fired gas turbines are potentially attractive alternatives to conventional steam cycle electric power generation because of their higher efficiencies. However, the high mineral matter content of coal creates problems with deposition, erosion, and corrosion of turbine components. Reported here is a study of methods to reduce the rate of formation of ash deposits, including a study of the effects of the addition of potential sulfur sorbents on downstream deposition problems. Methods studied involved modifying the combustion history of the coal particles in the combustor, cooling turbine components, and adding small amounts of aluminosilicate to the coal. The results show that the proper combination of these techniques can produce a two orders of magnitude reduction in the rate of ash deposit formation.     

Fast heuristic algorithms for rectilinear steiner trees

A fundamental problem in circuit design is how to connectn points in the plane, to make them electrically common using the least amount of wire. The tree formed, a Steiner tree, is usually constructed with respect to the rectilinear metric. The problem is known to be NP-complete; an extensive review of proposed heuristics is given. An early algorithm by Hanan is shown to have anO(n logn) time implementation using computational geometry techniques. The algorithm can be modified to do sequential searching inO(n ²) total time. However, it is shown that the latter approach runs inO(n ^3/2) expected time, forn points selected from anm×m grid. Empirical results are presented for problems up to 10,000 points.     

The experience of learning and using Smalltalk

The authors offer observations from their own experience learning and using Smalltalk. They report that they had trouble learning Smalltalk despite their fairly extensive programming backgrounds. They contend that new users will encounter several problems, especially if they try to learn the system through unguided exploration. They trace many of these problems to the large and diffuse nature of Smalltalk and to its generalist design     

A simple method of restoring lidfunction in facial nerve paralysis with permanent magnets (author''s transl)

Anxiety arising from masturbatory guilt plays a major role in the production of frigidity and impotence. Reduction of this anxiety through greater community awareness of the normality of masturbation is therefore a fertile area for the principles of preventive medicine to be applied.