Representations of the self in the near and distant future.

Seven studies provide evidence that representations of the self at a distant-future time point are more abstract and structured than are representations of the self at a near-future time point and that distant-future behaviors are more strongly related to general self-conceptions. Distant-future self-representations incorporate broader, more superordinate identities than do near-future self-representations (Study 1) and are characterized by less complexity (Study 2), more cross-situational consistency (Study 3), and a greater degree of schematicity (Study 4). Furthermore, people's behavioral predictions of their distant-future (vs. near-future) behavior are more strongly related to their general self-characteristics (Study 5), distant-future behaviors are seen as more self-expressive (Study 6), and distant-future behaviors that do not match up with acknowledged self-characteristics are more strongly rejected as reflections of the self (Study 7). Implications for understanding both the nature of the self-concept and the way in which distance may influence a range of self-processes are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic Scaling in Chemical Ecology

Natural rates of chemical production, release, and transport of fluid-borne molecules drive fundamental biological responses to these stimuli. The scaling of the field signaling environment to laboratory conditions recreates essential features of the dynamics and establishes ecological relevance. If appropriately scaled, laboratory simulations of physical regimes, coupled with natural rates of chemical cue/signal emission, facilitate interpretation of field results. From a meta-analysis of papers published in 11 journals over the last 22 years (1984-1986, 1994-1996, 2004-2006), complete dynamic scaling was rare in both field and laboratory studies. Studies in terrestrial systems often involved chemical determinations, but rarely simulated natural aerodynamics in laboratory wind tunnels. Research in aquatic (marine and freshwater) systems seldom scaled either the chemical or physical environments. Moreover, nearly all research, in all environments, focused on organism-level processes without incorporating the effects of individual-based behavior on populations, communities, and ecosystems. As a result, relationships between chemosensory-mediated behavior and ecological function largely remain unexplored. Outstanding exceptions serve as useful examples for guiding future research. Advanced conceptual frameworks and refined techniques offer exciting opportunities for identifying the ecological significance of chemical cues/signals in behavioral interactions and for incorporating individual effects at higher levels of biological organization.     

Evaluation of 3-trifluoromethyl-4-nitrophenol (TFM) residues following a lampricide treatment as a risk assessment to the endangered piping plover

To evaluate the risk to the federally endangered piping plover (Charadrius melodus) from exposure to 3-trifluoromethyl-4-nitrophenol (TFM) during a sea lamprey control treatment we collected and analyzed a series of water, sediment, and aquatic invertebrate samples for the presence of TFM before, during, and after treatment of the Little Two Hearted River, Luce County, Michigan in July 2008. Results of the analyses in water showed the treatment resulted in a maximum concentration of 1.14 mg/L TFM. Residues of TFM in water were greatest 50 m east of the mouth (0.73 mg/L TFM) and had decreased below detection at most of the sampling sites one day after treatment. Residues of TFM in sediment were greatest 50 m east of the mouth (105 ng/g TFM) with lower levels observed west of the mouth (3-5 ng/g TFM) the day of the treatment. Residues decreased rapidly and were below detection in most of the samples the day after treatment. Residues of TFM in caged mayflies were greatest one day after treatment (3,193 ng/g wet weight), decreased substantially by 4 days after treatment (74 ng/g), but were still present 8 days after treatment (80 ng/g). Based on results from this study the overall TFM exposure to adult piping plovers (0.425 mg/kg) was 85 times less than the estimated No Observable Effects Concentration (NOEC) of 36 mg/kg and was 17 times less than the NOEC for plover chicks (2.13 mg/kg) indicating the risk from sea lamprey control operations would likely be minimal.     

Results of the “Active by Choice Today” (ACT) randomized trial for increasing physical activity in low-income and minority adolescents.

Objective: This study reports the results of the “Active by Choice Today” (ACT) trial for increasing moderate-to-vigorous physical activity (MVPA) in low-income and minority adolescents. Design: The ACT program was a randomized controlled school-based trial testing the efficacy of a motivational plus behavioral skills intervention on increasing MVPA in underserved adolescents. Twenty-four middle schools were matched on school size, percentage minorities, percentage free or reduce lunch, and urban or rural setting before randomization. A total of 1,563 6th grade students (mean age, 11.3 years, 73% African American, 71% free or reduced lunch, 55% female) participated in either a 17-week (over one academic year) intervention or comparison after-school program. Main Outcome Measure: The primary outcome measure was MVPA based on 7-day accelerometry estimates at 2-weeks postintervention and an intermediate outcome was MVPA at midintervention. Results: At midintervention students in the intervention condition engaged in 4.87 greater minutes of MVPA per day (95% CI: 1.18 to 8.57) than control students. Students in intervention schools engaged in 9.11 min (95% CI: 5.73 to 12.48) more of MVPA per day than those in control schools during the program time periods; indicating a 27 min per week increase in MVPA. No significant effect of the ACT intervention was found outside of school times or for MVPA at 2-weeks postintervention. Conclusions: Motivational and behavioral skills programs are effective at increasing MVPA in low-income and minority adolescents during program hours, but further research is needed to address home barriers to youth MVPA. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Mesh‐independent matrix cracking and delamination modeling in laminated composites

The initiation and evolution of transverse matrix cracks and delaminations are predicted within a mesh‐independent cracking (MIC) framework. MIC is a regularized extended finite element method (x‐FEM) that allows the insertion of cracks in directions that are independent of the mesh orientation. The Heaviside step function that is typically used to introduce a displacement discontinuity across a crack surface is replaced by a continuous function approximated by using the original displacement shape functions. Such regularization allows the preservation of the Gaussian integration schema regardless of the enrichment required to model cracking in an arbitrary direction. The interaction between plies is anchored on the integration point distribution, which remains constant through the entire simulation. Initiation and propagation of delaminations between plies as well as intra‐ply MIC opening is implemented by using a mixed‐mode cohesive formulation in a fully three‐dimensional model that includes residual thermal stresses. The validity of the proposed methodology was tested against a variety of problems ranging from simple evolution of delamination from existing transverse cracks to strength predictions of complex laminates withouttextita priori knowledge of damage location or initiation. Good agreement with conventional numerical solutions and/or experimental data was observed in all the problems considered. Published 2011. This article is a US Government work and is in the public domain in the USA.