Enraizamento de estacas, crescimento e respostas anatômicas de mudas clonais de cacaueiro ao ácido indol-3-butírico Stem cutting rooting, growth and anatomical responses of cacao tree clonal changes to the indole-3-butyric acid

Avaliaram-se os efeitos do ácido indol-3-butírico (AIB) no crescimento e na morfologia interna de quatro clones de Theobroma cacao (CCN-10, CP-53, PS-1319 e CA-1.4). O AIB foi aplicado na base da estaca de caule, em talco inerte, nas concentrações de 2; 4; 6 e 8 g kg-1, juntamente com o controle (sem AIB). A avaliação do crescimento de raízes, caule e folhas dos quatro clones foi realizada aos 160 dias após o estaqueamento (DAE) para todas as concentrações de AIB, período também em que se realizou a coleta de material para os estudos anatômicos dos diversos órgãos, mas somente para a concentração de 4g kg-1 AIB e o controle. O clone CA-1.4 apresentou incremento na biomassa seca de raiz (BSR) com o aumento das concentrações de AIB, ao passo que, nos demais clones, houve diminuições de BSR a partir dos 4 g kg-1 AIB. O mesmo fato foi observado para a biomassa seca de caule (BSC) e de folha (BSF), exceto para a BSC do CCN-10 que não respondeu ao incremento das concentrações de AIB. Houve aumento de área foliar total para os clones CP-53 e PS-1319 com o incremento de AIB até 4 g kg-1, enquanto o aumento do número de folhas ocorreu somente para os clones CA-1.4 e CP-53 até as concentrações 8 e 4 g kg-1 AIB, respectivamente. Houve diminuição do número de estacas mortas para os clones CA-1.4 e CCN-10 até 8 g kg-1 de AIB e para o CP-53 até 4 g kg-1 de AIB. As melhores concentrações de AIB para o enraizamento de estacas de ramos dos clones de cacaueiros CP-53, PS-1319 e CCN-10 foram de 4, 4 e 6 g kg-1 AIB, respectivamente, enquanto para o clone CA-1.4 foi de 8 g kg-1 AIB; o aumento da concentração de AIB promoveu mudanças anatômicas nos órgãos vegetativos de todos os clones, influenciando na atividade do câmbio vascular e induzindo a formação de um maior número de raízes adventícias nas estacas.<br>The effects of indole-3-butyric acid (IBA) on growth and internal morphology of four clones of Theobroma cacao (CCN-10, CP-53, PS-1319 and CA-1.4) were evaluated. The IBA was applied in the base of stem cuttings, as an inert talc, in mixture concentrations of 2, 4, 6 and 8 g kg-1 together with the control, without IBA. The evaluation of the growth of roots, stem and leaves of the four clones were accomplished by 160 days after the cutting (DAC) for all the IBA concentrations. However, the anatomical studies of the several plant organs were also made to the 160 DAC, but only for the concentration of 4g kg-1 IBA and the control. The clone CA-1.4 presented increment in the root dry biomass (RDB) with the increase of the IBA concentrations, while for the other clones there were decreases of RDB starting from the 4 g kg-1 IBA. The same fact was observed for the stem and leaf dry biomass, except for CCN-10 that did not answer to the increment of the concentrations of IBA. There was an increase of the total leaf area for the clones CP-53 e PS-1319 with the increment of the IBA (concentration up to 4 g kg-1), while the leaves number only increased for the clones CA-1.4 and CP-53, concentrations up to 8 and 4 g kg-1 IBA, respectively. There was a decrease in the number of dead cuttings for the clones CA-1.4 and CCN-10 (up 8 g kg-1) of IBA and for the CP-53 (up to 4 g kg-1 of IBA). The best IBA concentrations for the branch cutting rooting of the cacao clones CP-53, PS-1319 and CCN-10 were of 4, 4 and 6 g kg-1 respectively, while for the clone CA-1.4 was the one of 8 g kg-1; the increase of the IBA concentration promoted anatomical changes in the plant organs of all the clones, influencing the activity of the vascular cambium in the stem and inducing the formation of a larger number of adventitious roots in the stem cuttings

Adverse late health outcomes among children treated with 3D radiotherapy techniques: Study design of the Dutch pediatric 3D-RT study.

BACKGROUND: Adverse late health outcomes after multimodal treatment for pediatric cancer are diverse and of prime interest. Currently available evidence and survivorship care guidelines are largely based on studies addressing side-effects of two dimensional planned radiotherapy. AIMS: The Dutch pediatric 3D-planned radiotherapy (3D-RT) study aims to gain insight in the long-term health outcomes among children who had radiotherapy in the 3D era. Here, we describe the study design, data-collection methods, and baseline cohort characteristics. METHODS AND RESULTS: The 3D-RT study represents an expansion of the Dutch Childhood Cancer Survivor study (DCCSS) LATER cohort, including pediatric cancer patients diagnosed during 2000-2012, who survived at least 5 years after initial diagnosis and 2 years post external beam radiotherapy. Individual cancer treatment parameters were obtained from medical files. A national infrastructure for uniform collection and archival of digital radiotherapy files (Computed Tomography [CT]-scans, delineations, plan, and dose files) was established. Health outcome information, including subsequent tumors, originated from medical records at the LATER outpatient clinics, and national registry-linkage. With a median follow-up of 10.9 (interquartile range [IQR]: 7.9-14.3) years after childhood cancer diagnosis, 711 eligible survivors were identified. The most common cancer types were Hodgkin lymphoma, medulloblastoma, and nephroblastoma. Most survivors received radiotherapy directed to the head/cranium only, the craniospinal axis, or the abdominopelvic region. CONCLUSION: The 3D-RT study will provide knowledge on the risk of adverse late health outcomes and radiation-associated dose-effect relationships. This information is valuable to guide follow-up care of childhood cancer survivors and to refine future treatment protocols

Spectral and non-linear analysis of thalamocortical neural mass model oscillatory dynamics

The chapter is organised in two parts: In the first part, the focus is on a combined power spectral and non-linear behavioural analysis of a neural mass model of the thalamocortical circuitry. The objective is to study the effectiveness of such ‘multi-modal’ analytical techniques in model-based studies investigating the neural correlates of abnormal brain oscillations in Alzheimer’s disease (AD). The power spectral analysis presented here is a study of the ‘slowing’ (decreasing dominant frequency of oscillation) within the alpha frequency band (8 – 13 Hz), a hallmark of Electroencephalogram (EEG) dynamics in AD. Analysis of the nonlinear dynamical behaviour focuses on the bifurcating property of the model. The results show that the alpha rhythmic content is maximal at close proximity to the bifurcation point — an observation made possible by the ‘multi-modal’ approach adopted herein. Furthermore, a slowing in alpha rhythm is observed for increasing inhibitory connectivity — a consistent feature of our research into neuropathological oscillations associated with AD. In the second part, we have presented power spectral analysis on a model that implements multiple feed-forward and feed-back connectivities in the thalamo-cortico-thalamic circuitry, and is thus more advanced in terms of biological plausibility. This study looks at the effects of synaptic connectivity variation on the power spectra within the delta (1 – 3 Hz), theta (4 – 7 Hz), alpha (8 – 13 Hz) and beta (14 – 30 Hz) bands. An overall slowing of EEG with decreasing synaptic connectivity is observed, indicated by a decrease of power within alpha and beta bands and increase in power within the theta and delta bands. Thus, the model behaviour conforms to longitudinal studies in AD indicating an overall slowing of EEG

Soil microbial biomass under different management and tillage systems of permanent intercropped cover species in an orange orchard

To mitigate soil erosion and enhance soil fertility in orange plantations, the permanent protection of the inter-rows by cover species has been suggested. The objective of this study was to evaluate alterations in the microbial biomass, due to different soil tillage systems and intercropped cover species between rows of orange trees. The soil of the experimental area previously used as pasture (Brachiaria humidicola) was an Ultisol (Typic Paleudult) originating from Caiuá sandstone in the northwestern part of the State of Paraná, Brazil. Two soil tillage systems were evaluated: conventional tillage (CT) in the entire area and strip tillage (ST) (strip width 2 m), in combination with different ground cover management systems. The citrus cultivar 'Pera' orange (Citrus sinensis) grafted onto 'Rangpur' lime rootstock was used. Soil samples were collected after five years of treatment from a depth of 0-15 cm, under the tree canopy and in the inter-row, in the following treatments: (1) CT and an annual cover crop with the leguminous species Calopogonium mucunoides; (2) CT and a perennial cover crop with the leguminous peanut Arachis pintoi; (3) CT and an evergreen cover crop with Bahiagrass Paspalum notatum; (4) CT and a cover crop with spontaneous Brachiaria humidicola grass vegetation; and (5) ST and maintenance of the remaining grass (pasture) of Brachiaria humidicola. Soil tillage and the different cover species influenced the microbial biomass, both under the tree canopy and in the inter-row. The cultivation of brachiaria increased C and N in the microbial biomass, while bahiagrass increased P in the microbial biomass. The soil microbial biomass was enriched in N and P by the presence of ground cover species and according to the soil P content. The grass species increased C, N and P in the soil microbial biomass from the inter-row more than leguminous species