Successive Cambia: A Developmental Oddity or an Adaptive Structure?

BackgroundSecondary growth by successive cambia is a rare phenomenon in woody plant species. Only few plant species, within different phylogenetic clades, have secondary growth by more than one vascular cambium. Often, these successive cambia are organised concentrically. In the mangrove genus Avicennia however, the successive cambia seem to have a more complex organisation. This study aimed (i) at understanding the development of successive cambia by giving a three-dimensional description of the hydraulic architecture of Avicennia and (ii) at unveiling the possible adaptive nature of growth by successive cambia through a study of the ecological distribution of plant species with concentric internal phloem.ResultsAvicennia had a complex network of non-cylindrical wood patches, the complexity of which increased with more stressful ecological conditions. As internal phloem has been suggested to play a role in water storage and embolism repair, the spatial organisation of Avicennia wood could provide advantages in the ecologically stressful conditions species of this mangrove genus are growing in. Furthermore, we could observe that 84.9% of the woody shrub and tree species with concentric internal phloem occurred in either dry or saline environments strengthening the hypothesis that successive cambia provide the necessary advantages for survival in harsh environmental conditions.ConclusionsSuccessive cambia are an ecologically important characteristic, which seems strongly related with water-limited environments

Exercise and Physical Therapy Interventions for Children with Ataxia: a systematic review

The effectiveness of exercise and physical therapy for children with ataxia is poorly understood. The aim of this systematic review was to critically evaluate the range, scope and methodological quality of studies investigating the effectiveness of exercise and physical therapy interventions for children with ataxia. The following databases were searched: AMED, CENTRAL, CDSR, CINAHL, ClinicalTrials.gov, EMBASE, Ovid MEDLINE, PEDro and Web of Science. No limits were placed on language, type of study or year of publication. Two reviewers independently determined whether the studies met the inclusion criteria, extracted all relevant outcomes, and conducted methodological quality assessments. A total of 1988 studies were identified, and 124 full texts were screened. Twenty studies were included in the review. A total of 40 children (aged 5-18 years) with ataxia as a primary impairment participated in the included studies. Data were able to be extracted from eleven studies with a total of 21 children (aged 5-18 years), with a range of cerebellar pathology. The studies reported promising results but were of low methodological quality (no RCTs), used small sample sizes and were heterogeneous in terms of interventions, participants and outcomes. No firm conclusions can be made about the effectiveness of exercise and physical therapy for children with ataxia. There is a need for further high-quality child-centred research

Relacionamento terapêutico com criança no período perioperatório: utilização do brinquedo e da dramatização

Este estudo de caso tem o objetivo de analisar o relacionamento terapêutico desenvolvido entre aluna de enfermagem e uma criança de 3 anos , durante o período perioperatório, utilizando o brinquedo e a dramatização para facilitar a explicação dos procedimentos e dos objetos do hospital para a criança.Ouso do brinquedo mostrou-se uma forma adequada para comunicar-se efetivamente com a criança, e para prepará-la para a intervenção cirúrgica, pois, através da dramatização, ela participou ativamente dos procedimentos, mostrando que compreendia e aceitava o que estava acontecendo,nãoapresentando em nenhum momento medo ou ansiedade diante do ambiente do hospital e dos procedimentos cirúrgicos. Ao final do relacionamento, a mãe e a equipe cirúrgica avaliaram positivamente o preparo da criança para a cirurgia

Temperature variation among mangrove latitudinal range limits worldwide

Mangroves are mainly tropical tree species that occur on either side of the equator and because temperature decreases with increasing latitude, the latitudinal limits of mangroves are expected to be mainly controlled by temperature-related drivers. Here, we hypothesized that the mangrove genera (Avicennia and Rhizophora) have the same limiting temperature at all of their upper latitudinal limits at the global scale. We first derived six parameters from monthly mean sea surface temperature (SST) and air temperature (AT). Furthermore, we investigated whether the variation in these temperature parameters is related (i) to the position of the limit, (ii) to specific temperature requirements of congeneric species and/or (iii) to aridity. All temperature-based parameters derived from AT and SST are highly variable among the upper latitudinal limits of Avicennia and Rhizophora. Hence, we found no common isotherms to characterize the limits of the two mangrove genera, which contradict previous studies. The high temperature variation among limits can be due to partial range filling towards the latitudinal limits. This is supported by the higher warmest month temperatures at the latitudinal limits of the northern hemisphere as compared to the southern hemisphere. However, temperature parameters at limits, with no or less than 250 km of available poleward coast, are not different from other limits, and adult tree height at the limits is not correlated with the temperature-based variables. Mean air temperature is warmer at limits with an arid climate, suggesting mechanisms of compensation towards higher temperatures when Avicennia and Rhizophora have to cope with both aridity and low temperature. © 2012 Springer-Verlag.SCOPUS: ar.jSCOPUS: ar.jinfo:eu-repo/semantics/publishe