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41.
Mycorrhizal fungi symbioses can be critical determining if established seedlings survive or not. Currently, in remnant forests, plants and their fungal symbionts are exposed to varied anthropomorphic effects related to urbanization, however, little is known about their impact on this association. We investigated the relationship between mycorrhizal fungi and tree seedling survival along an urbanization gradient. We planted three species of temperate tree seedlings (Acer rubrum, Carya ovata, and Quercus rubra) in three landscapes: urban, suburban, and rural. We measured the percent of root length colonized by mycorrhizal fungi and monitored survival during their first growing season. We analyzed mycorrhizal colonization as a function of landscape type (urban-rural) and additional variables known to contribute to mycorrhizal colonization (phosphorus, nitrogen, initial plant height). We then analyzed seedling survival as a function of the degree of mycorrhizal fungi colonization associated with the landscape gradient and of additional environmental factors (light and soil moisture). Within a species we found no changes in the levels of mycorrhizal fungi colonization across the urbanization gradient. Each species, however, had markedly different levels of colonization. Survival of A. rubrum was independent of mycorrhizal colonization, while C. ovata and Q. rubra had a significant positive response to increased mycorrhizal fungi. These findings highlight the resilience of mycorrhizal communities across the rural-urban gradient typical of this region, but they also underscore the potential sensitivity of some tree species to lower levels of mycorrhizal fungi colonization.  相似文献   
42.
The urban domestic gardens that are part of urban green areas have become a very important element due to their ecosystematic benefits and the poor information about them. Information regarding the floristic richness of three socioeconomic stratifications from the city of Heredia, Costa Rica is presented in this study. Research was conducted from October 2011 to May 2012. Information was collected using a semi-structured questionnaire, which was provided to 61 garden owners, including the owner’s personal data, time living in the dwelling, area of the property and the garden, variation of its size in time and the garden’s location on the property. In addition, a floristic inventory was conducted in each garden as well as a taxonomic identification of all plants. Vegetative forms and substrates were also noted. Characteristics of the gardens and their owners were then analyzed to determine the relationship of species richness between the three sites studied. The number of plant species recorded was 618, corresponding to 102 families (19 % exotic). Regarding geographical origin, 64, 4 % were exotic, 35,6 % native. Orchidaceae (93 spp.) and Araceae (39 spp.) were the most dominant families. The variables of garden area and location and owner's age determined the garden’s floristic richness. In addition, the garden’s area and vegetative forms varied among the sites studied probably due to socioeconomic differences among them. Diversity of pioneer plants increased with the garden’s area. In sum, this research provides important floristic information of domestic gardens, since, being private property, data about them is scarce and municipal management guidelines are nonexistent.  相似文献   
43.
We present the results of the use of a cognitive behavioral therapeutic intervention tool to improve the mental, physical, and social health of a group of long-term unemployed women in Spain. Method: We sent automated text messages (SMS) to the mobile phones of long-term unemployed women selected at random from public social services. During a 28-day intervention period, women received four daily automated text messages on her mobile phone on a predetermined hourly schedule. We measured depression symptoms at the start and end of the intervention and we analyzed qualitative data to determine the acceptability of a remote SMS program. Results: Depression symptoms using the Personal Health Questionnaire-9 (PHQ-9), went from an average of 13.8 at baseline to 4.9 at the end of 28 days (p?=?0.89). One hundred percent of the women reported that they liked receiving the text messages and most found them helpful.  相似文献   
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Theory and Society - This article presents fashion as a mechanism of domination and political legitimacy, focusing on Soviet-type state socialist regimes. In particular, it documents some dynamics...  相似文献   
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The Organic Law on the Improvement of the National Education Quality (Ley Orgánica de Reforma de la Calidad Educativa) readdressed one of the most significant educational issues: educational policies related to immigrant students. Therefore, this is an appropriate moment to evaluate these types of policies in three singular Spanish regions: Madrid, Catalonia and Andalusia. This article presents an analysis of the measures taken in three Spanish regions: Madrid, Catalonia and Andalusia in response to students’ reception, acceptance and enrolment of immigrant students. A qualitative methodology based on the comparative method is used. Diverse similarities, but also specific characteristics and differences, can be found among the three models associated with each region. There are several significant differences that can be appreciated, such as the institutional role, as well as other specific measures. However, singular features are also identified, such as the diverse policies for the use of the vehicular language in each of the cases. Finally, the comparisons highlight various critical aspects, such as attention devoted to the students’ native language and progress towards intercultural education in school strategies and planning.  相似文献   
48.
If voters vote strategically, is it useful to offer them the possibility of expressing nuanced opinions, or would they always overstate the intensity of their preferences? For additive voting rules, say that a ballot is extremal if it is neither abstention-like nor can be expressed as a mixture of the available ballots. We give a sufficient condition for strategic equivalence: if two rules share the same set of extremal ballots (up to an homothetic transformation), they are strategically equivalent in large elections. This condition is also necessary for the strategic equivalence of positional rules. These results do not hold for small electorates.  相似文献   
49.
There is a gap in the Marriage and Family Therapy literature regarding clients', therapists', and family judges' theories of change in relational therapy for family violence. We conducted in-depth interviews with eleven court-referred families, their therapists, and two family judges in Bogota, Colombia. Interviews focused on their expectations of therapy outcomes, their understanding of change, and their evaluation of individual and relational therapy outcomes. We followed a grounded theory approach to data analysis. Analyses showed that therapists, family judges, and clients hold different expectations and theories regarding therapeutic change. Findings are discussed based on existing research on clients' and therapists' ideas about change. Implications for future research and practice are presented.  相似文献   
50.
The restructuring of production resulting from the Port Modernization Law (Law 8.630/90) caused significant changes in work organization of Brazilian Ports. In the case of Mucuripe (Fortaleza, Ceará), in particular, the changes were very intense as Mucuripe is an old port that, before the Law, had labor regulation being governed by Trade Unions. This paper aims to present the perceptions of Union Representatives on the changes brought about by the Law on work organization in the port of Fortaleza, its influence in the organization and in the way the Unions deal with this new reality. Open and exploratory interviews were conducted with representatives of occasional labor workers registered in the Port of Fortaleza OGMO (Org?o Gestor de M?o de Obra, Labor Regulation Management). The analysis of the collected material in the interviews was based on the technique of content analysis proposed by Bardin (1979). Trade Unions have undergone a great loss of power and it has reflected in a relative inability to perform its function and to fight for the rights of the workers. The obvious Trade Unions weakness - a reduction of strikes and less unionized workers - reflects the dominating ideology of capital.  相似文献   
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