24 research outputs found

    Numerical modeling evaluation of the impacts of shrimp farming operations on long-term coastal lagoon morphodynamics

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    This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record.In coastal systems occupied by large clusters of pond aquaculture farms, hydro-sedimentary processes may be impacted by the combination of water management strategies that are individually performed by each cultivation unit. In this study, a numerical model was used to evaluate 100-year morphological alterations in two different idealized coastal lagoons surrounded by shrimp ponds. One is broadly based on the Guaraíras Lagoon System (RN, Brazil) where shrimp farming has developed since 1924, and the other is highly simplified to systematically investigate pond aquaculture impacts. Information obtained through numerical simulations (e.g., hypsometry changes, evolution of morphological parameters, balance of sediment volumes, bed level changes, and residual bed shear stress variations) provided coastal impact assessments for a wide variety of aquaculture occupation scenarios. Key findings include (i) water exchange operations performed by aquaculture farms are capable of modifying the morphological equilibrium state of a coastal lagoon system, especially if carried out synchronously to the local tidal oscillation; (ii) water intake operations regularly performed by pond aquaculture activity increase sediment import to the system; (iii) depth and configuration of tidal channels are modified when pond aquaculture is present. The modeling approach and analyses presented here can be extended to other systems that are under the influence of shrimp farming activity and be adopted to support novel regulations for the conservation of coastal habitats and to contribute to the sustainable development of pond aquaculture in the coastal zone.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil (CAPES

    On the Perception of Newcomers: Toward an Evolved Psychology of Intergenerational Coalitions

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    Human coalitions frequently persist through multiple, overlapping membership generations, requiring new members to cooperate and coordinate with veteran members. Does the mind contain psychological adaptations for interacting within these intergenerational coalitions? In this paper, we examine whether the mind spontaneously treats newcomers as a motivationally privileged category. Newcomers—though capable of benefiting coalitions—may also impose considerable costs (e.g., they may free ride on other members, they may be poor at completing group tasks). In three experiments we show (1) that the mind categorizes coalition members by tenure, including newcomers; (2) that tenure categorization persists in the presence of orthogonal and salient social dimensions; and (3) that newcomers elicit a pattern of impressions consistent with their probable ancestral costs. These results provide preliminary evidence for a specialized component of human coalitional psychology: an evolved concept of newcomer

    Bright light therapy versus physical exercise to prevent co-morbid depression and obesity in adolescents and young adults with attention-deficit/hyperactivity disorder: study protocol for a randomized controlled trial

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    Background: The risk for major depression and obesity is increased in adolescents and adults with attention-deficit / hyperactivity disorder (ADHD) and adolescent ADHD predicts adult depression and obesity. Non-pharmacological interventions to treat and prevent these co-morbidities are urgently needed. Bright light therapy (BLT) improves day– night rhythm and is an emerging therapy for major depression. Exercise intervention (EI) reduces obesity and improves depressive symptoms. To date, no randomized controlled trial (RCT) has been performed to establish feasibility and efficacy of these interventions targeting the prevention of co-morbid depression and obesity in ADHD. We hypothesize that the two manualized interventions in combination with mobile health-based monitoring and reinforcement will result in less depressive symptoms and obesity compared to treatment as usual in adolescents and young adults with ADHD. Methods: This trial is a prospective, pilot phase-IIa, parallel-group RCT with three arms (two add-on treatment groups [BLT, EI] and one treatment as usual [TAU] control group). The primary outcome variable is change in the Inventory of Depressive Symptomatology total score (observer-blinded assessment) between baseline and ten weeks of intervention. This variable is analyzed with a mixed model for repeated measures approach investigating the treatment effect with respect to all three groups. A total of 330 participants with ADHD, aged 14 – < 30 years, will be screened at the four study centers. To establish effect sizes, the sample size was planned at the liberal significance level of α = 0.10 (two-sided) and the power of 1-β = 80% in order to find medium effects. Secondary outcomes measures including change in obesity, ADHD symptoms, general psychopathology, health-related quality of life, neurocognitive function, chronotype, and physical fitness are explored after the end of the intervention and at the 12-week follow-up. This is the first pilot RCT on the use of BLT and EI in combination with mobile health-based monitoring and reinforcement targeting the prevention of co-morbid depression and obesity in adolescents and young adults with ADHD. If at least medium effects can be established with regard to the prevention of depressive symptoms and obesity, a larger scale confirmatory phase-III trial may be warranted.The trial is funded by the EU Framework Programme for Research and Innovation, Horizon 2020 (Project no. 667302). Funding period: January 2016–December 2020. This funding source had no role in the design of this study and will not have any role during its execution, analyses, interpretation of the data, or decision to submit results. Some local funds additionally contributed to carry out this study, especially for the preparation of the interventions: FBO research activity is by the Spanish Ministry of Economy and Competitiveness – MINECO (RYC-2011-09011) and by the University of Granada, Plan Propio de Investigación 2016, Excellence actions: Unit of Excellence on Exercise and Health (UCEES)
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