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The capacity for marine fishes to perform aerobically (aerobic scope) is predicted to control their thermal tolerance and, thus, the impact that rapid climate change will have on their populations. We tested the effect of increased water temperatures on the resting and maximum rates of oxygen consumption in five common coral reef fishes at Lizard Island on the northern Great Barrier Reef, Australia. All species exhibited a decline in aerobic capacity at elevated water temperatures (31, 32 or 33 °C) compared with controls (29 °C); however, the response was much stronger in two cardinalfishes, Ostorhinchus cyanosoma and O. doederleini, compared with three damselfishes, Dascyllus anuarus, Chromis atripectoralis and Acanthochromis polyacanthus. Aerobic scope of the two cardinalfishes was reduced by nearly half at 31 °C compared with 29 °C, and virtually all capacity for additional oxygen uptake was exhausted by 33 °C. In contrast, the three damselfishes retained over half their aerobic scope at 33 °C. Such differences in thermal tolerance between species, and possibly families, suggest that the community structure of reef fish assemblages might change significantly as ocean temperatures increase. Populations of thermally tolerant species are likely to persist at higher temperatures, but populations of thermally sensitive species could decline on low-latitude reefs if individual performance falls below levels needed to sustain viable populations.

Analogies have been argued to be central in the process of establishing conceptual growth, making overt connections and carryover into an intended cognitive domain, and providing a generative venue for developing conceptual understanding inherent in constructivist learning. However, students' specific uses of analogies for constructing arguments are not well understood. Specifically, the results of preservice teachers' knowledge gains are not widely studied. Although we would hope that engaging preservice science teachers in exemplary lessons would assist them in using and generating analogies more expertly, it is not clear whether or how such curricula would affect their learning or teaching. This study presents an existence proof of how preservice science teachers used analogies embedded in their course materials Physics by Inquiry. This fine-grained analysis of small group discourse revealed three distinct roles of analogies including the development of: (a) cognitive process skills, (b) scientific conceptual understanding, and (c) social contexts for problem solving. Results suggest that preservice teachers tend to overgeneralize the analogies inserted by curriculum materials, map irrelevant features of analogies into collaborative problem solving, and generate personal analogies, which counter scientific concept development. Although the authors agree with the importance of collaborative problem solving and the insertion of analogies for preservice teachers' conceptual development, we believe much more needs to be understood before teachers can be expected to construct and sustain effective learning environments that rely on using analogies expertly. Implications for teacher preparation are also discussed. © 2003 Wiley Periodicals, Inc. J Res Sci Teach 40: 443–463, 2003

The purpose of this study was to compare the worldview of Native American students of the Traditional Kickapoo Band with the worldview encountered in the science classroom. The qualitative study investigated the worldview expressed in science instruction by conducting periodic observations in two classrooms over an 18-month period, teacher interviews, and text evaluations. StudentsO worldviews were investigated during individual and group interviews, classroom observations, science activities, and social interaction. Twenty-eight Kickapoo students, two teachers, and eight nonteaching members of the community participated in the study. Adult members of the Kickapoo Band were interviewed and asked to reflect on the educational and cultural norms of the students. A variable-oriented analysis revealed differences in epistemology, preferred methods of teaching/learning, values, spatial/temporal orientation, cultural rules for behavior, and perspective of the place of humans in the natural world. The study revealed significant worldview differences, none of which would prevent Kickapoo students from being full participants in the scientific community, but many of which may be preventing them from being successful in the science classroom. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 111–132, 1998.

This study explores the beliefs about reform of life science teachers in central Texas who were retained to teach Coordinated Thematic Science I. In particular, we were interested in identifying the beliefs that serve as the foundation for the grade 7 life science teachers' intentions to introduce physical science activities in the life science classes they teach. To accomplish this purpose, we selected four teachers, using purposeful sampling procedures. We also adapted an empirical model for investigating rational decisionmaking, the Theory of Planned Behavior, for use in an interview format. Two additional data sources were used to triangulate our findings set out in seven assertions developed from the 52 pages of transcribed interviews. Our results call attention to the need for all three levels of education—state, district, and school—to cooperate in implementing science curriculum reform in Texas. © 1995 John Wiley & Sons, Inc.

The purpose of this paper is threefold. First, we set out to describe a context for understanding events that fuel the need to reform secondary science education in Texas. Next, we present the results of a survey of the knowledge, beliefs, and attitudes of a group of central Texas science teachers related to implementing Coordinated Thematic Science (CTS) instruction, who were surveyed after field testing preliminary CTS instructional materials. Last, we argue that caution must be exercised in the design of inservice programs to prepare life science teachers in Texas to teach a coordinated thematic Science I course to rising Grade 7 students by the target date of Fall, 1994.

The theory of reasoned action (Ajzen & Fishbein, 1980; Fishbein & Ajzen, 1975) was used to predict and understand Korean high school students' track choice for college entrance. First-year high school students (N = 665) from four representative regions of Korea participated in the study. The survey instruments were questionnaires developed according to the guidelines of the TRA. The target behavior of interest in this study was Korean students' choice of the science track when they completed the track application forms during the first year of high school. Predictors included TRA model and external variables. Multiple regression and the structural equation modeling with LISREL (Joreskog & Sorbom, 1986) were used to analyze the data. The TRA was found to be applicable for understanding and predicting track choice, with minor modifications. Subjective norm was found to exert a direct influence on personal beliefs and the target behavior.

A stereoselective [2,3]-sigmatropic (Wittig) rearrangement of prop-2-ynyl 2-silyl allyl ethers 22 leading to E-vinyl silanes, e.g.23 is described. Stereospecific protiodesilylation of 23, via26, next produces the Z-alkene 27. sp-sp and sp-sp2 Coupling reactions between the acetylenic alcohol 5 produced from 27, and 3-bromoprop-2-ynol or 3-bromoprop-2-enol THP ether, then leads to the key intermediates 3 and 31 in leukotriene B41 synthesis.

1. Nonadrenergic, noncholinergic (NANC) nerves mediate vasodilatation in guinea-pig pulmonary artery (PA) by both endothelium-dependent and endothelium-independent mechanisms. The transmitter(s) involved in the endothelium-independent pathway have not yet been identified. We have therefore investigated the possibility that nitric oxide (NO) and guanosine 3',5'-cyclic monophosphate (cyclic GMP) may mediate this neural vasodilator response in guinea-pig branch PA rings denuded of endothelium. 2. Electric field stimulation (EFS, 50 V, 0.2 ms) induced a frequency-dependent (1-24 Hz), tetrodotoxin-sensitive relaxation of the U44069-precontracted PA rings in the presence of adrenergic and cholinergic blockade. 3. The NO synthase inhibitors NG-monomethyl L-arginine (L-NMMA, 100 microM) and NG-nitro L-arginine methyl ester (L-NAME, 30 microM), and the guanylyl cyclase inhibitor methylene blue (5 microM) inhibited the EFS (16 Hz)-induced relaxation by 53 +/- 5, 74 +/- 9 and 82 +/- 9% respectively (n = 5-7, P < 0.01, compared with control rings). 4. Excess concentrations of L-, but not D-arginine (300 microM) completely reversed the inhibitory effect of L-NMMA. 5. The EFS-elicited relaxation (4 Hz) was potentiated by 1 microM zaprinast, a type V phosphodiesterase inhibitor which inhibits guanosine 3':5'-cyclic monophosphate (cyclic GMP) degradation, but was unaffected by 0.1 microM zardaverine, a type III/IV phosphodiesterase inhibitor which inhibits cyclic AMP degradation. 6. EFS (50 V, 0.2 ms, 16 Hz) induced a 3 fold increase in tissue cyclic GMP content, an action which was inhibited by L-NMMA (100 microM). 7. Pyrogallol (100microM), a superoxide anion generator, also inhibited the EFS-induced relaxation by 53 +/- 9%, and this effect was prevented by superoxide dismutase.8. Chemical sympathetic denervation with 6-hydroxydopamine had no effect on the relaxant response to EFS in the endothelium-denuded PA rings.9. In endothelium-denuded branch PA rings at resting tone, L-NMMA (100 microM) significantly augmented the adrenergic contractile response, an effect which was completely reversed by L-arginine,but not by D-arginine. In the same groups of vessel rings, L-NMMA had no significant effect on the matched contractile response to exogenous noradrenaline.10. These results suggest that NO may be released from intramural nerve endings other than adrenergic nerves (probably NANC nerves), and this leads to vasodilatation via activation of guanylyl cyclase.

The purpose of this study was to explore the utility of the theory of planned behavior model developed by social psychologists for understanding and predicting the behavioral intentions of secondary science students regarding enrolling in physics. In particular, the study used a three-stage causal model to investigate the links from external variables to behavioral, normative, and control beliefs; from beliefs to attitudes, subjective norm, and perceived behavioral control; and from attitudes, subjective norm, and perceived behavioral control to behavioral intentions. The causal modeling method was employed to verify the underlying causes of secondary science students' interest in enrolling physics as predicted in the theory of planned behavior. Data were collected from secondary science students (N = 264) residing in a central Texas city who were enrolled in earth science (8th grade), biology (9th grade), physical science (10th grade), or chemistry (11th grade) courses. Cause-and-effect relationships were analyzed using path analysis to test the direct effects of model variables specified in the theory of planned behavior. Results of this study indicated that students' intention to enroll in a high school physics course was determined by their attitude toward enrollment and their degree of perceived behavioral control. Attitude, subjective norm, and perceived behavioral control were, in turn, formed as a result of specific beliefs that students held about enrolling in physics. Grade level and career goals were found to be instrumental in shaping students' attitude. Immediate family members were identified as major referents in the social support system for enrolling in physics. Course and extracurricular conflicts and the fear of failure were shown to be the primary beliefs obstructing students' perception of control over physics enrollment. Specific recommendations are offered to researchers and practitioners for strengthening secondary school students' intentions to study physics.

The purpose of this study was to explore the utility of the theory of planned behavior for predicting the behavioral intentions of teachers enrolled in the Institute in Physical Science, an EESA, Title II program funded by the Texas Higher Education Coordinating Board. In particular, the study investigated three determinants of teachers' behavioral intentions (BI) set forth in the theory of planned behavior, namely, attitude toward the behavior (AB), subjective norm (SN), and perceived behavioral control (PBC). The behavior of interest in this study was the intention of teachers in grades 5/6 or 9/10 who were enrolled in the Institute to use 50% of the activities and investigations completed in the program with students they would teach during the next school year. Data were collected from 50 elementary and secondary teachers. Simple and hierarchical regression analyses were used to determine the relative contributions of attitude, subjective norm, and perceived behavioral control (and their interactions) to the prediction of behavioral intention. Results of this study indicated that attitude, subjective norm, and perceived behavioral control made significant contributions to the prediction of behavioral intention. Examination of the data blocked on external variables revealed attitude toward the behavior to be the single most important predictor of behavioral intention. Intent to perform the behavior appears to be totally under the control of most teachers, with little need for social support and with ample resources and sufficient opportunities available to perform the behavior.

The determinants of intentions to enroll in a high school science course were investigated, using the theory of reasoned action, among earth science students enrolled in a middle school located in a middle-income, suburban community in central Texas. The sample consisted of 5 of 14 eighth-grade earth science classes, randomly selected for this study. Classes contained Caucasian and minority students, male and female, of differing science abilities who were grouped according to general academic abilities—basic, average, and gifted and talented. The prediction of behavioral intention of sample participants was tested using four external variables, attitude, and subjective norm (Direct-Full Effects Model), attitude and subjective norm alone (Direct-Reduced Effects Model), and disaggregated data on attitude and subjective norm (Indirect Effects Model). Results of the study revealed attitude and subjective norm to be the sole predictors of behavioral intention for the aggregated data, but to be differentially effective for groups formed on the basis of sex, ethnicity, general ability, and science ability. Evidence is presented to show that the relative contributions of attitude and subjective norm to the prediction of behavioral intention varies among students depending upon their sex, ethnicity, general ability, and science ability. Results of the study are discussed in terms of increasing the enrollment of all students in elective science courses.

Differences in classroom climate and science related attitudes were investigated among junior high school science classes and students in Taiwan. The sample consisted of 1,269 students enrolled in 40 science classes distributed equally among ten junior high schools, five metropolitan and five rural. Classes were further classified according to sex (21 boys and 19 girls classes) and ability (19 high and 21 low ability classes). Using the Learning Environment Inventory (Anderson, Walberg, & Fraser, 1982) to measure climate, science classes in metropolitan schools, more than rural, were found to be characterized by Speed, Friction, Favoritism, Difficulty, Cliqueness, and Competitiveness. No differences were found in the classroom climates of classes in which students were grouped according to sex or ability. Using the Test of Science-Related Attitudes (Fraser, 1981), students in science classes in metropolitan schools, in contrast to rural, expressed more positive attitudes toward the Social Implications of Science, Adoption of Scientific Attitudes, and Attitude to Scientific Inquiry. Boys more than girls recorded high scores on Leisure Interest in Science and Career Interest in Science. High ability students were found to have higher scores on Attitude to Scientific Inquiry than did low ability students. When examining the relationship between the 15 subscale scores of the LEI and the seven subscale scores of the TOSRA for the 40 classes, only 9 out of 105 correlations proved to be significant. Most differences in climate, attitude, and their interactions were attributed to school location rather than to student characteristics.

The study investigated the benefits of a matching model of instruction for students enrolled in ninth grade physical science classes in one high school in a small, urban school district. Based on social learning theory, three independent variables were identified for purposes of matching: need level, cognitive style, and locus of control; attitude and achievement outcomes served as the dependent variables. Results of separate analyses of covariance revealed that attitude toward science in general improved with matching, but achievement, attitude toward physical science, attitude toward instruction, and attitude toward the teacher did not improve. Recommendations for subsequent “matching” experiments are discussed in light of the findings in this investigation.