3 resultados para Conceptual models

em Digital Commons at Florida International University


Relevância:

70.00% 70.00%

Publicador:

Resumo:

We developed a conceptual ecological model (CEM) for invasive species to help understand the role invasive exotics have in ecosystem ecology and their impacts on restoration activities. Our model, which can be applied to any invasive species, grew from the eco-regional conceptual models developed for Everglades restoration. These models identify ecological drivers, stressors, effects and attributes; we integrated the unique aspects of exotic species invasions and effects into this conceptual hierarchy. We used the model to help identify important aspects of invasion in the development of an invasive exotic plant ecological indicator, which is described a companion paper in this special issue journal. A key aspect of the CEM is that it is a general ecological model that can be tailored to specific cases and species, as the details of any invasion are unique to that invasive species. Our model encompasses the temporal and spatial changes that characterize invasion, identifying the general conditions that allow a species to become invasive in a de novo environment; it then enumerates the possible effects exotic species may have collectively and individually at varying scales and for different ecosystem properties, once a species becomes invasive. The model provides suites of characteristics and processes, as well as hypothesized causal relationships to consider when thinking about the effects or potential effects of an invasive exotic and how restoration efforts will affect these characteristics and processes. In order to illustrate how to use the model as a blueprint for applying a similar approach to other invasive species and ecosystems, we give two examples of using this conceptual model to evaluate the status of two south Florida invasive exotic plant species (melaleuca and Old World climbing fern) and consider potential impacts of these invasive species on restoration.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The theoretical analysis and research of cultural activities have been limited, for the most part, to the study of the role the public sector plays in the funding and support of nonprofit Arts organizations. The tools used to evaluate this intervention follow a macroeconomic perspective and fail to account for microeconomic principles and assumptions that affect the behavior of these organizations. This dissertation describes through conceptual models the behavior of the agents involved in the artistic process and the economic sectors affected by it. The first paper deals with issues related to economic impact studies and formulates a set of guidelines that should be followed when conducting this type of study. One of the ways to assess more accurately the impact culture has in a community is by assuming that artists can re-create the public space of a blight community and get it ready for a regeneration process. The second paper of this dissertation assumes just that and explains in detail all the cultural, political, economic and sociological interactions that are taking place in the Arts-led regeneration process in Miami Beach, Florida. The paper models the behavior of these agents by indicating what their goals and decision process mechanisms are. The results give support to the claim that the public space artists create in a city actually stimulate development. The third paper discusses the estimation of a demand function for artistic activities, specifically the New World Symphony (NWS) located in Miami Beach, Florida. The behavior of the consumers and producers of NWS' concerts is modeled. The results support the notion that consumers make their decisions based, among other things, on the perceived value these concerts have. Economists engage in the analysis of the effects of cultural activities in a community since many cities rely on them for their development. The history of many communities is not told by their assembly lines and machinery anymore but by their centers of entertainment, hotels and restaurants. Many cities in Europe and North America that have seen the manufacturing sector migrate to the South are trying to face the demands of the new economy by using the Arts as catalysts for development. ^

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Purpose: Early onset of sexual activity has been linked to later substance abuse. Our study aimed to further describe the associations between Latina mothers’ and daughters’ early sexual activity and adult substance abuse. Methods: A survey was conducted with 92 Latina mother–daughter dyads whose members never experienced sexual abuse. Childhood sexual experience was defined as the occurrence of a consensual sexual encounter at the age of 15 years or younger. Substance abusers were identified by the extent of substance use during the 12 months prior to the interview. Path analysis was used to fit our conceptual models to the data. Main findings: Daughters’ current, adult substance abuse was associated independently with: their own childhood sexual experience (odds ratio [OR] = 6.0) and mothers’ current, adult substance abuse (OR = 2.0). Compared with daughters who first experienced sex after the age of 19, the odds of using substances were 17.7 times higher among daughters who had childhood sexual experience and 3.8 times higher among daughters who first experienced sex between the age of 16–19 years. Explicitly, sexual experiences between the ages of 16–19 years were also risk factors for later adult substance abuse. Mothers’ childhood sexual experience (OR = 7.3) was a strong predictor for daughters’ childhood sexual experience. Conclusions: Our study supported a link between mother and daughter childhood sexual experience among Latinas, and indicated it is a correlate of adult substance abuse. Family based substance abuse prevention efforts and future longitudinal studies should consider maternal childhood sexual experience as a potential indication of risk for Latina daughters.