In conversation: high school students talk to students about tobacco use and prevention strategies.

The purpose of this multi-site qualitative study is to explore how adolescents talk about tobacco use. Sixty-six students in four high schools became co-researchers and led focus group interviews with 205 fellow students. From the interviews, the authors develop a story line that reports how adolescents begin smoking, how smoking becomes a pervasive influence, how attitudes form about smoking, what it means to be a smoker, and, ultimately, student suggestions for tobacco use prevention.

Location, time, and temperature dependence of digestion in simple animal tracts.

In this paper, we develop plug flow reactor models that simultaneously investigate how reaction and absorption, morphological differences, and temperature influence nutrient acquisition rates in simple, tubular animal guts. We present analytical solutions to the resulting reaction-advection equations that model these processes, and we obtain formulas giving the throughflow speed that maximizes the absorption rate. The model predicts that the optimal digestion speed increases as the ratio of the rate of enzyme breakdown to the rate of absorption increases.

GeV electrons from ultraintense laser interaction with highly charged ions.

Ultraintense laser interactions with highly charged ions are investigated using three-dimensional Monte Carlo simulations. Results show that ultraenergetic GeV electrons may be produced for highly charged ions chosen so that their electrons remain bound during the rise time of the laser pulse, and so that the electrons are ionized when the laser is near its maximum amplitude, which satisfies the best injection condition for subsequent laser acceleration.

The polyelectrolyte behavior of actin filaments: a 25Mg NMR study.

Under physiological conditions, filamentous actin (F-actin) is a polyanionic protein filament. Key features of the behavior of F-actin are shared with other well-characterized polyelectrolytes, in particular, duplex DNA. For example, the bundle formation of F-actin by polyvalent cations, including divalent metal ions such as Mg2+, has been proposed to be a natural consequence of the polyelectrolyte nature of actin filaments [Tang and Janmey (1996) J.

Use of resistant mutants to characterize the target of mycobacillin in Aspergillus niger membranes.

The mycobacillin-sensitive Aspergillus niger strain G3Br and resistant mutants of it did not show any differences in their total lipid content, although the amounts of phospholipids and sterols, particularly phosphatidylcholine and cholesterol, were lower in resistant cells. Mycobacillin resistance was accompanied by an increase in the phase-transition temperature of plasma membrane preparations. When exposed to mycobacillin, resistant and sensitive cells did not differ qualitatively with respect to most released materials (lysine, proline, Pi, Na+, K+, Ca2+); however, the release of ATP was completely inhibited in resistant cells unless they were exposed to concentrations of mycobacillin exceeding their respective MIC value.

Situational Interest in Literary Text.

This study examined relationships among text characteristics, situational interest, two measures of text understanding, and personal responses when reading a literary text. A factor analysis of ratings made after reading revealed six interrelated text characteristics. Of these, suspense, coherence and thematic complexity explained 54% of the variance in interest.

Weight Loss Behavior in High School Wrestling: Wrestler and Parent Perceptions.

Self-reports of weight loss knowledge, attitudes, and methods in a sample of 125 high school wrestlers are described. These responses are compared to perceptions of 88 wrestlers' parents regarding their son's weight loss behaviors. Responses to survey questionnaires indicated that wrestlers were highly likely to deliberately lose weight for wrestling and that they most commonly used increased exercise, caloric restriction, and fluid restriction as weight loss techniques.

Age-Related Increases in the Shoulder Strength of High School Wrestlers.

The purpose of this investigation was to examine age-related differences in absolute and relative isokinetic shoulder strength of high school wrestlers. A total of 122 high school wrestlers (M age = 16.31±1.

Presomal morphology and development of Prosthorhynchus formosus, Prosthenorchis elegans, and Moniliformis dubius (Acanthocephala).

Larvae removed at one-day intervals from laboratory infected intermediate hosts provided material for a comparative study of presomal development in Prosthorhynchus formosus (Van Cleave, '18) Travassos, '26, Prosthenorchis elegans (Diesing, 1851) Travassos, '15, and Moniliformis dubius Meyer, '33. Acanthellae begin development soon after entering intermediate hosts' hemocoels, and by the 18th day all three species possess three nuclear masses representing primordia of the proboscis, proboscis receptacle and ganglion, and trunk musculature and genitalia. Presomal development of P.