Espécies crípticas em Pagamea coriacea sensu lato (Rubiaceae): evidências morfológicas, ecológicas e de comportamento reprodutivo em um contexto simpátrico

In this study we explore morphological and ecological variation in sympatric populations of Pagamea coriacea s.l. - a species complex from white-sand vegetation in the Amazon. A total of 147 trees were sampled and monitored at three nearby sites in Central Amazon, Brazil. Multivariate analyses of morphology indicated two distinct groups (A and B), which also differed in bark type, each containing subgroups associated with sexual dimorphism. However, a single hermaphroditic individual was observed within group B. As expected, all pistillate plants produced fruits, but 23% of the staminate plants of group B, and 5% of group A also produced fruits. This variation suggests that the sexual systems of both groups are between dioecy and gynodioecy. There was an overlap in flowering phases between the two groups, but the pattern of floral maturation differed. Ecologically, plants of group B were found in more shaded habitats and over sandstone bedrocks, while group A was prevalent in deeper sandy soils as canopy plants. The significances of morphological and environmental differences were tested by a multivariate analysis of variance, and a canonical discriminant analysis assessed the importance of variables. The coexistence in sympatry of two discrete morphological groups in the P. coriacea s.l., with different habitat preferences and reproductive behaviors, indicates they represent distinct species.O objetivo deste estudo foi testar se o complexo de espécies Pagamea coriacea inclui múltiplas espécies, usando evidências morfológicas, ecológicas e de comportamento reprodutivo. Um total de 147 árvores foram amostradas e monitoradas em três locais próximos na Amazônia Central, Brasil. Análises multivariadas de dados morfológicos indicaram dois grupos discretos (A e B), que coincidem com diferenças no tipo de casca, cada um por sua vez com subgrupos que representam dimorfismo sexual. Contudo, um indivíduo distintamente hermafrodita foi encontrado no grupo B. Todas as plantas pistiladas produziram frutos, mas também foram observados frutos para 23% das plantas estaminadas do grupo B, e para 5% das estaminadas do grupo A. Essa variação sugere que ambos grupos possuem um sistema sexual entre dioicia e ginodioicia. Houve sobreposição das fases de floração e frutificação entre os dois grupos, mas o padrão de maturação de flores foi diferente. Quanto ao hábitat, o grupo B predominou em situações de sombra e em solos arenosos rasos sobre lajes de pedra, enquanto o grupo A ocorreu em solos arenosos mais profundos e no dossel da vegetação. A coexistência de dois grupos morfológicos discretos no complexo P. coriacea s.l., com diferenças ecológicas e de comportamento reprodutivo, indica que correspondem a duas espécies distintas

Alzheimer and β-amyloid-treated fibroblasts demonstrate a decrease in a memory-associated GTP-binding protein, Cp20

The two proteins most consistently identified in the brains of patients with Alzheimer disease (AD) have been β-amyloid and tau, whose roles in the physiology or pathophysiology of brain cells are not fully understood. To identify other protein(s) involved in AD that have been implicated in physiological contexts, we undertook to analyze a specific memory-associated protein, Cp20, in fibroblasts from AD and control donors. Cp20, a GTP- binding protein that is a member of the ADP-ribosylation factor family, was significantly decreased in fibroblasts from AD patients. Normal control fibroblasts exposed to 10 nM β-amyloid, the same concentration that induced AD-like K⁺ changes in control fibroblasts, showed a similar decrease in Cp20. Since it has been previously demonstrated that Cp20 is a potent regulator of K⁺ channels, these findings suggest that changes in this memory-associated protein may explain previously observed differences in AD K⁺ channels and suggest a pathophysiologic involvement linked to soluble β- amyloid metabolism that could contribute to the characteristic memory loss of AD

Obesidade e sobrepeso em adolescentes: relação com atividade física, aptidão física, maturação biológica e "status" socioeconômico Obesity and overweight in adolescents: relationship among physical activity, physical fitness, biological maturity and socioeconomic status

Este estudo relaciona atividade física (AF), aptidão física (AptF), maturação biológica e "status" socioe-conômico (ESE) com as prevalências de risco ponderal de adolescentes. Foi desenvolvido no Concelho de Santo Tirso, região norte de Portugal e amostrou 961 alunos (463 meninos e 498 meninas) com idades variando entre os 11 e os 18 anos. O índice de massa corporal foi utilizado para estabelecer o "status" ponderal com base nos pontos de corte propostos por COLE et al. A AF foi avaliada através do questionário de Baecke e a AptF com quatro testes da bateria Fitnessgram. O ESE foi estimado a partir do acesso aos escalões atribuídos pela Ação Social Escolar e a maturação biológica a partir do "offset" maturacional. A análise estatística foi efetuada nos "softwares" Pepi versão 4.0 e SPSS 18.0. O nível de significância foi mantido em 5%. Seis por cento dos alunos eram obesos e 19,5% tinham sobrepeso; meninos e meninas têm prevalências semelhantes de sobrepeso e obesidade. Os níveis médios de AF foram baixos a moderados independentemente do sexo ou "status" ponderal. Os meninos eram mais ativos que as meninas (p < 0,001), mas não se registraram diferenças significativas entre os alunos com obesidade e sobrepeso e os normoponderais. Na AptF, um número superior a 50%, foi considerado inapto, i.e, não obtiveram taxas de sucesso em todos os testes. Os alunos com sobrepeso e obesidade foram mais inaptos. Alunos com "offset" maturacional mais avançado e os mais novos tinham mais chances de ter sobrepeso e obesidade, mas não houve relação significativa entre o ESE e o "status" ponderal. Concluímos que os jovens Tirsenses apresentam prevalências de obesidade e sobrepeso elevadas, são relativamente pouco ativos e, em grande medida, fisicamente inaptos.<br>The aim of this study was to relate physical activity, physical fitness, maturation and socioeconomic status with the prevalence of ponderal risk in adolescents. This was a transversal study made in the Council of Santo Tirso in the north of Portugal. The sample consisted of 961students (463 boys and 498 girls), aged 11 to 18. Body mass index was used to establish ponderal status based on the cut points from COLE et al. Physical activity was evaluated by Baecke's questionnaire and physical fitness with four tests from Fitnessgram battery. Socioeconomic status was ranked according to the grades assigned by state school subsidies, while biological maturation estimation was based on maturational offset. Software programs Pepi version 4.0 and SPSS 18.0 were used for statistical analysis. The level of significance was kept in 5%. Six percent of the target students were obese and 19.5% had overweight. The prevalences of overweight and obesity were similar between genders. The medium levels of physical activity were low or moderate, independent of gender or ponderal status. Boys were more active than girls (p < 0.001) but no significant differences were found between the students with obesity and overweight and normoponderal ones. On what concerns physical fitness, a high percentage of students (above 50%) were considered inapt and failed the tests. Students suffering from overweight and obesity were clearly more inapt. Students with more advanced maturational offset as well as the youngest ones were more likely to present overweight and obesity but no meaningful relationship was found between socioeconomic position and ponderal status. We concluded that young students from S. Tirso had high prevalences of obesity and overweight, were relatively inactive and largely physically unfit

Counter-global cases for place: Contesting displacement in globalising Kuala Lumpur Metropolitan Area

10.1080/00420980412331297627Urban Studies41122447-246