916 resultados para The two circuits of the urban economy


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Biological assays that have been performed on different types of Brazilian propolis have shown that type 6 propolis (G6) has a strong antimicrobial activity and a low flavonoid content. This study aimed to evaluate the correlation between the phenolic composition and the biological activities displayed by propol is G6 from the state of Bahia and green propol is, also known as type 12 (G12). The values of the flavonoids and the total phenolics in propol is G6 were different than those in propolis G12. Although the G12 variety presented greater antioxidant activity, propolis G6 proved to have greater antimicrobial and cytotoxic activities. The results showed that the phenolic compounds may not be the only compounds responsible for the biological activity. More detailed studies of the chemical composition and an assessment or the biological activity are required to establish the quality of propolis.

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Two versions of the threshold contact process ordinary and conservative - are studied on a square lattice. In the first, particles are created on active sites, those having at least two nearest neighbor sites occupied, and are annihilated spontaneously. In the conservative version, a particle jumps from its site to an active site. Mean-field analysis suggests the existence of a first-order phase transition, which is confirmed by Monte Carlo simulations. In the thermodynamic limit, the two versions are found to give the same results. (C) 2012 Elsevier B.V. All rights reserved.

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Objective: The present study aimed to investigate the individual and family determinants of being overweight among children younger than 10 years of age. Design: Cross-sectional survey. Direct data on children's age, food intake, physical activity, type of transportation used and anthropometric measurements, as well as the education level of the mothers, were collected by trained interviewers. Setting: Population-based study in the city of Santos, Brazil. Subjects: A total of 531 children under 10 years of age (302 aged <6 years, >= 6 aged years), living in the city of Santos. Results: The overall prevalence of overweight and obesity (BMI-for-age Z-score >1) was 35.4% for children under 6 years and 38.9% for children aged 6-10 years. The socio-economic status of the family was associated with being overweight for both age groups. Logistic regression analysis showed that the lower the socio-economic status, the higher the likelihood of being overweight, among both younger children (OR = 7.73; P = 0.02) and older children (OR = 1.98; P = 0.04). The use of active transportation was associated with a lower likelihood of being overweight, but only among younger children (OR = 1.70; P = 0.05). Conclusions: Socio-economic status seems to be an important individual-level determinant of overweight in children. Public policies should consider promoting the use of active transportation, as the results showed it to have a positive effect on reducing overweight issues. The high prevalence of overweight in younger children suggests that this age group should be a priority in health-promoting interventions.

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The nucleotide sequences of the 5S rRNA multigene family and their distribution across the karyotypes in 2 species of Gymnotiformes, genus Gymnotus (G. sylvius and G. inaequilabiatus) were investigated by means of fluorescence in situ hybridization (FISH). The results showed the existence of 2 distinct classes of 5S rDNA sequences in both species: class I and class II. A high conservative pattern of the codifying region of the 5S rRNA gene was identified, contrasting with significant alterations detected in the nontranscribed spacer (NTS). The presence of TATA-like sequences along the NTS of both species was an expected occurrence, since such sequences have been associated with the regulation of the gene expression. FISH using 5S rDNA class I and class II probes revealed that both gene classes were collocated in the same chromosome pair in the genome of G. sylvius, while in that of G. inaequilabiatus, class II appeared more disperse than class I. Copyright (C) 2012 S. Karger AG, Basel

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Despite the general belief that the interaction between extrafloral nectaries (EFNs) and ants is mutualistic, the defensive function of EFNs has been poorly documented in South American savannas. In this article, we evaluate the potential impact of EFNs (benefits and costs) on two species of plants from the dry areas of Central Brazil, Anemopaegma album and Anemopaegma scabriusculum (Bignoniaceae). In particular, we characterize the composition of substances secreted by the EFNs, test whether EFNs attract ants, and whether ants actually present a defensive role, leading to reduced herbivory and increased plant fitness. Histochemical analyses indicated that EFNs from both species of Anemopaegma secrete an exudate that is composed of sugars, and potentially lipids and proteins. Furthermore, EFNs from both species were shown to present a significant role in ant attraction. However, contrary to common expectations, ants were not found to protect plants against herbivore attack. No effect was found between ant visitation and flower or fruit production in A. album, while the presence of ants led to a significant decrease in flower production in A. scabriusculum. These results suggest that EFNs might present a similar cost and benefit in A. album, and a higher cost than benefit in A. scabriusculum. Since the ancestor of Anemopaegma occupied humid forests and already presented EFNs that were maintained in subsequent lineages that occupied savannas, we suggest that phylogenetic inertia might explain the presence of EFNs in the species of Anemopaegma in which EFNs lack a defensive function.

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Guapira graciliflora and Neea theifera are taxonomically related species of the tribe Pisoneae. Both species are found in the same environment, the Brazilian Cerrado, and therefore, are subjected to similar selective pressures. These species occur in oligotrophic environments, yet contain high concentrations of nitrogen in their leaves. The present study was carried out to investigate the ecological role of nitrogen in herbivory on these species. The differences in the N content, compositions of secondary N-metabolites, mechanical resistance, and water content between their leaves indicate that these species have different adaptations as defense mechanisms. In both species, their high nitrogen content seems to promote herbivory. The presence of secondary nitrogen metabolites does not prevent the species from suffering intense damage by herbivores on their early leaves. The herbivory rates observed were lower for mature leaves of both species than for young leaves. In G. graciliflora, nutritional content and leaf hardness are the most important variables correlated with reduction of herbivory rates, whereas in N. theifera, N compounds are also correlated with herbivory rates. Despite the differences in the strategies of these two species, they exhibit a similar efficiency of protection against natural enemies because their total herbivory rates are similar. The difference in their N defense allocation may imply benefits for survival under Cerrado conditions. We briefly discuss the oligotrophic habitat conditions of the studied plants and possible advantages of their strategies of N accumulation and metabolic uses. (C) 2011 Elsevier B.V. All rights reserved.

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Abstract Background Citrus canker is a disease that has severe economic impact on the citrus industry worldwide. There are three types of canker, called A, B, and C. The three types have different phenotypes and affect different citrus species. The causative agent for type A is Xanthomonas citri subsp. citri, whose genome sequence was made available in 2002. Xanthomonas fuscans subsp. aurantifolii strain B causes canker B and Xanthomonas fuscans subsp. aurantifolii strain C causes canker C. Results We have sequenced the genomes of strains B and C to draft status. We have compared their genomic content to X. citri subsp. citri and to other Xanthomonas genomes, with special emphasis on type III secreted effector repertoires. In addition to pthA, already known to be present in all three citrus canker strains, two additional effector genes, xopE3 and xopAI, are also present in all three strains and are both located on the same putative genomic island. These two effector genes, along with one other effector-like gene in the same region, are thus good candidates for being pathogenicity factors on citrus. Numerous gene content differences also exist between the three cankers strains, which can be correlated with their different virulence and host range. Particular attention was placed on the analysis of genes involved in biofilm formation and quorum sensing, type IV secretion, flagellum synthesis and motility, lipopolysacharide synthesis, and on the gene xacPNP, which codes for a natriuretic protein. Conclusion We have uncovered numerous commonalities and differences in gene content between the genomes of the pathogenic agents causing citrus canker A, B, and C and other Xanthomonas genomes. Molecular genetics can now be employed to determine the role of these genes in plant-microbe interactions. The gained knowledge will be instrumental for improving citrus canker control.

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PURPOSE: Stigma is a frequent accompaniment of mental illness leading to a number of detrimental consequences. Most research into the stigma connected to mental illness was conducted in the developed world. So far, few data exist on countries in sub-Saharan Africa and no data have been published on population attitudes towards mental illness in Ghana. Even less is known about the stigma actually perceived by the mentally ill persons themselves. METHOD: A convenience sample of 403 participants (210 men, mean age 32.4 ± 12.3 years) from urban regions in Accra, Cape Coast and Pantang filled in the Community Attitudes towards the Mentally Ill (CAMI) questionnaire. In addition, 105 patients (75 men, mean age 35.9 ± 11.0 years) of Ghana's three psychiatric hospitals (Accra Psychiatry Hospital, Ankaful Hospital, Pantang Hospital) answered the Perceived Stigma and Discrimination Scale. RESULTS: High levels of stigma prevailed in the population as shown by high proportions of assent to items expressing authoritarian and socially restrictive views, coexisting with agreement with more benevolent attitudes. A higher level of education was associated with more positive attitudes on all subscales (Authoritarianism, Social Restrictiveness, Benevolence and Acceptance of Community Based Mental Health Services). The patients reported a high degree of experienced stigma with secrecy concerning the illness as a widespread coping strategy. Perceived stigma was not associated with sex or age. DISCUSSION: The extent of stigmatising attitudes within the urban population of Southern Ghana is in line with the scant research in other countries in sub-Saharan Africa and mirrored by the experienced stigma reported by the patients. These results have to be seen in the context of the extreme scarcity of resources within the Ghanaian psychiatric system. Anti-stigma efforts should include interventions for mentally ill persons themselves and not exclusively focus on public attitudes.

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Recent research with several species of nonhuman primates suggests sophisticated motor-planning abilities observed in human adults may be ubiquitous among primates. However, there is considerable variability in the extent to which these abilities are expressed across primate species. In the present experiment, we explore whether the variability in the expression of anticipatory motor-planning abilities may be attributed to cognitive differences (such as tool use abilities) or whether they may be due to the consequences of morphological differences (such as being able to deploy a precision grasp). We compared two species of New World monkeys that differ in their tool use abilities and manual dexterity: squirrel monkeys, Saimiri sciureus (less dexterous with little evidence for tool use) and tufted capuchins, Sapajus apella (more dexterous and known tool users). The monkeys were presented with baited cups in an untrained food extraction task. Consistent with the morphological constraint hypothesis, squirrel monkeys frequently showed second-order motor planning by inverting their grasp when picking up an inverted cup, while capuchins frequently deployed canonical upright grasping postures. Findings suggest that the lack of ability for precision grasping may elicit more consistent second-order motor planning, as the squirrel monkeys (and other species that have shown a high rate of second-order planning) have fewer means of compensating for inefficient initial postures. Thus, the interface between morphology and motor planning likely represents an important factor for understanding both the ontogenetic and phylogenetic origins of sophisticated motor-planning abilities.

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Recent research with several species of nonhuman primates suggests sophisticated motor-planning abilities observed in human adults may be ubiquitous among primates. However, there is considerable variability in the extent to which these abilities are expressed across primate species. In the present experiment, we explore whether the variability in the expression of anticipatory motor-planning abilities may be attributed to cognitive differences (such as tool use abilities) or whether they may be due to the consequences of morphological differences (such as being able to deploy a precision grasp). We compared two species of New World monkeys that differ in their tool use abilities and manual dexterity: squirrel monkeys, Saimiri sciureus (less dexterous with little evidence for tool use) and tufted capuchins, Sapajus apella (more dexterous and known tool users). The monkeys were presented with baited cups in an untrained food extraction task. Consistent with the morphological constraint hypothesis, squirrel monkeys frequently showed second-order motor planning by inverting their grasp when picking up an inverted cup, while capuchins frequently deployed canonical upright grasping postures. Findings suggest that the lack of ability for precision grasping may elicit more consistent second-order motor planning, as the squirrel monkeys (and other species that have shown a high rate of second-order planning) have fewer means of compensating for inefficient initial postures. Thus, the interface between morphology and motor planning likely represents an important factor for understanding both the ontogenetic and phylogenetic origins of sophisticated motor-planning abilities. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

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This thesis provides a comparison of the ideas of caring and love as they appear in the works of Plato and Frankfurt. Frankfurt, a contemporary philosopher, maintains that an individual arrives at the most meaningful life through understanding what it is that heor she cares about the most. Interestingly, the instances of eros in Plato's Symposium and Phaedrus resonate with this idea. We see throughout these erotic dialogues similarities to Frankfurt's notions of care and love.Throughout his many works, Frankfurt provides us with several distinct features of care and love. This thesis offers an in depth discussion of each of these features andalso provides commentary from other contemporary philosophers who are familiar with Frankfurt's work. In addition, this thesis applies these features of care and love to Plato's erotic dialogues, and emphasizes areas in which Plato and Frankfurt agree and those inwhich they disagree. In essence, it becomes apparent that while there are many similarities between the ideas of these two prominent thinkers, Plato and Frankfurt do not agree about what constitutes the best human life. Plato maintains that the best life is onespent dedicated to philosophy and in pursuit of the 'good'. Frankfurt, on the other hand,imposes no such limitations on what we should consider the best life because people are likely to have different life experiences that lead them to care about and love different things. Instead he suggests that the best or most meaningful human life is one in which a person spends his or her life caring about the things he or she does, indeed, care aboutand loving those things he or she does, indeed, love.