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Notes: This report describes the evaluation methodology of the Tri-Ministry Study—a school-based trial evaluating the effectiveness of three universal programs: (a) a classwide social skills program (SS), (b) a partner reading program (RE); and, (c) a combination of both (SS & RE), to reduce and prevent behavioural maladjustment among children in the primary division (up to grade 3) of Ontario schools. The trial was done between 1991 and 1995. Sixty schools in 11 boards of education took part and were assigned randomly to program(s) during the study. Contributing to the evaluation database are detailed follow-up assessments (observations, ratings, and standard tests) on 2439 children. Three-level growth trajectory models are used to evaluate program effects. The analysis presented for illustration in this report focuses on reading achievement measured by the Wide Range Achievement Test. A companion paper presents the results of the study and discusses important methodological and programmatic issues applicable to this and other prevention studies in the field.

Notes: This report describes program effects of the Tri-Ministry Study—a school-based, longitudinal trial carried out over a 5-year period to assess the effectiveness of classwide social skills training (SS), partner reading (RE), and a combination of both (SS & RE) to reduce maladjustment among children in the primary division (up to grade 3) of Ontario schools. It also places these effects in the context of other school-based prevention studies and discusses them in view of important methodological and programmatic issues. The incremental effects attributable to the intervention programs were small and sporadic. There were statistically significant increases in prosocial behaviour observed in the playgrounds of intervention schools with no differentiation by program type. Furthermore, there was some evidence—a reduction in teacher and parent-rated externalising problems—that the combination of SS & RE and SS alone may have had modest beneficial effects. A review of nine other school-based studies, which evaluated universally delivered mental health prevention programs in general populations of students, revealed similar mixed results. There are both methodologic and programmatic issues implicated in the weak findings that have been reported to date. These issues need to be addressed to advance knowledge about the potential impact of mental-health prevention initiatives delivered universally through school-based programs. A companion paper gives the specific details on the programs, randomisation of schools, selection of subjects, measurements, and analysis.

Notes: Unstable self-esteem is thought to reflect fragile and vulnerable feelings of self-worth that are affected by specific positive and negative events. Direct evidence for this contention is lacking, however. To redress this situation, we examined the extent to which level and stability of self-esteem predicted the impact that everyday positive and negative events had on individuals’ feelings about themselves. Participants recorded the most positive and most negative event that occurred each day Monday through Thursday for a period of 2 weeks. They then indicated the extent to which each event made them feel better or worse about themselves. As anticipated, negative and positive events had a greater impact on the self-feelings of individuals with unstable as opposed to stable self-esteem (although the effect for positive events was marginal). Additional findings indicated that event qualities (i.e., self-esteem relevance and concerns about social acceptance/rejection) could account for the unstable self-esteem/greater reactivity link for negative events, but not for positive events. Negative, but not positive, events had a greater impact on the self-feelings of individuals with low as compared to high levels of self-esteem. Theoretical implications are discussed.

Notes: The Fokker-Planck equation and molecular-based grand friction tensor are derived for the problem of rotational and translational motions of a structured Brownian particle, including the presence of a structured wall. Using the method of multiple time scales, it is shown that the time independent, grand friction tensor for the Brownian particle includes, in a general way, terms that account for the fluid molecular mediated interactions with the wall. The resulting Fokker-Planck equation has important applications in processes involving site-specific adsorption of macromolecules, such as affinity chromotography, biological separations, and numerous cellular processes involving attachment of macromolecules. © 1999 American Institute of Physics.

Notes: C4 plants contribute ≈ 20% of global gross primary productivity, and uncertainties regarding their responses to rising atmospheric CO2 concentrations may limit predictions of future global change impacts on C4-dominated ecosystems. These uncertainties have not yet been considered rigorously due to expectations of C4 low responsiveness based on photosynthetic theory and early experiments. We carried out a literature review (1980–97) and meta-analysis in order to identify emerging patterns of C4 grass responses to elevated CO2, as compared with those of C3 grasses. The focus was on nondomesticated Poaceae alone, to the exclusion of C4 dicotyledonous and C4 crop species. This provides a clear test, controlled for genotypic variability at family level, of differences between the CO2-responsiveness of these functional types. Eleven responses were considered, ranging from physiological behaviour at the leaf level to carbon allocation patterns at the whole plant level. Results were also assessed in the context of environmental stress conditions (light, temperature, water and nutrient stress), and experimental growing conditions (pot size, experimental duration and fumigation method). Both C4 and C3 species increased total biomass significantly in elevated CO2, by 33% and 44%, respectively. Differing tendencies between types in shoot structural response were revealed: C3 species showed a greater increase in tillering, whereas C4 species showed a greater increase in leaf area in elevated CO2. At the leaf level, significant stomatal closure and increased leaf water use efficiency were confirmed in both types, and higher carbon assimilation rates were found in both C3 and C4 species (33% and 25%, respectively). Environmental stress did not alter the C4 CO2-response, except for the loss of a significant positive CO2-response for above-ground biomass and leaf area under water stress. In C3 species, stimulation of carbon assimilation rate was reduced by stress (overall), and nutrient stress tended to reduce the mean biomass response to elevated CO2. Leaf carbohydrate status increased and leaf nitrogen concentration decreased significantly in elevated CO2 only in C3 species. We conclude that the relative responses of the C4 and C3 photosynthetic types to elevated CO2 concur only to some extent with expectations based on photosynthetic theory. The significant positive responses of C4 grass species at both the leaf and the whole plant level demand a re-evaluation of the assumption of low responsiveness in C4 plants at both levels, and not only with regard to water relations. The combined shoot structural and water use efficiency responses of these functional types will have consequential implications for the water balance of important catchments and range-lands throughout the world, especially in semiarid subtropical and temperate regions. It may be premature to predict that C4 grass species will lose their competitive advantage over C3 grass species in elevated CO2.

Notes: Slow Pathway Ablation. Introduction: The relationship between temperature at the electrode-tissue interface and the loss of AV and ventriculoatrial (VA) conduction is not established, and the optimal target temperature for the slow pathway approach to radiofrequency ablation of AV nodal reentrant tachycardia (AVNRT) is unknown. Therefore, the purpose of this study was to compare target temperatures of 48°C and 60°C during the slow pathway approach to ablation of AVNRT. Methods and Results: The study included 138 patients undergoing ablation for AVNRT. Patients undergoing slow pathway ablation using closed-loop temperature monitoring were randomly assigned to a target temperature of either 48°C or 60°C. The primary success rates were 76% in the patients assigned to 48°C and 100% in the patients assigned to 60°C (P 〈 0.01). The ablation procedure duration (33 ± 31 min vs 26 ± 28 min; P = 0.2), fluoroscopic time (25 ± 15 min vs 24 ± 16 min; P = 0.5), and mean number of applications (9.3 ± 6.5 vs 7.8 ± 8.1; P = 0.3) were similar in patients assigned to 48° and 60°C, respectively. The mean temperature (46.1°± 24.8°C vs 48.7°± 3.2°C; P 〈 0.01), the temperature associated with junctional ectopy (48.1°± 2.0°C vs 53.5°± 3.5°C, P 〈 0.0001), and the frequency of VA block during junctional ectopy (24.6% vs 37.2%; P 〈 0.0001) were less in the patients assigned to 48°C compared to 60°C. The frequency of transient or permanent AV block was similar in each group (2.8% vs 3.6%; P = 0.2). In the 60°C group, only 12% of applications achieved an electrode temperature of 60°C. During follow-up of 9.9 ± 4.2 months, there was one recurrence of AVNRT in the 48°C group and none in the 60°C group. Conclusions: Compared to 48°C, a target temperature of 60°C during radiofrequency slow pathway ablation is associated with a higher primary success rate and a higher incidence of VA block during junctional ectopy induced by the radiofrequency energy. AV block is not more common with the higher target temperature, but only if VA conduction is aggressively monitored during applications of radiofrequency energy.

Notes: Zohar (two-dimensions, particle-in-cell) [C. K. Birdsall and A. B. Langdon, Plasma Physics via Computer Simulation (McGraw–Hill, New York, 1985)] simulations of ultra intense laser beams boring into overdense plasmas whose parameters are guided by the fast-ignitor concept and radiography applications are presented. Complex low frequency magnetic field structures, narrow channel formation, and beam deflection are all evident. Particle tracking diagnostics elucidate the nature of the currents that produce and interact with these static magnetic fields which are larger than 109 G for simulations at 1021 W/cm2 in a 50nc plasma. Tracking electron orbits provides a more complete understanding of the hot electron generation as the short pulse, high intensity laser penetrates overdense plasma. Particles which constitute the current in the narrow channel are partially confined by the low frequency magnetic field. In contrast, the return current particles on the outside of the channel are defocused by the high magnetic field and move away from the channel.

Notes: The materials studied here include SmCo5, GdCo5, Sm2TM17, Gd2TM17, Nd9.4Pr4.6Fe80B6, Alnico, SrFe12O19, and PtCo (TM=transition metal). For the first time, the thermal expansion data α(⊥) and α((parallel)) for the eight materials from as low as −180 °C to as high as 1250 °C have been reported. α(⊥) is the thermal expansion coefficient in the base plane and α((parallel)) is the coefficient in the c axis. All anisotropic materials tested show thermal expansion anisotropy (TEA). The degree of TEA is defined as γ=α(⊥)/α((parallel)). The γ has been observed to be related to the degree of magnetocrystalline anisotropy field HA. SmCo5 has the highest HA (350 kOe) and the highest γ (2.5). All the materials show thermal anomaly with a changing slope for α((parallel)) near Tc and near phase transformation temperatures. The magnitude of thermal anomaly has been observed to be related to the magnitude of spontaneous magnetization (SMZ). The most distinct thermal anomalies are observed for Nd9.4Pr4.6Fe80B6, in which both α(⊥) and α((parallel)) show a deep valley near Tc, and a peak at around the spin-tilt temperature. Nd–Fe–B type material has the highest SMZ and the largest thermal anomaly of all the permanent magnets. Spontaneous magnetostriction occurs mainly in the c axis for RE–Co alloys (RE=rare earth), and in all directions for Nd–Fe–B type alloys. A rubber band model is used to describe the spontaneous magnetostriction force. © 1999 American Institute of Physics.