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As oil and gas exploration is moving to deeper waters, a key challenge is to design risers in harsh environments. Steel catenary risers (SCR) are cost-effective solutions that have been used in offshore developments due to their simplicity and robustness. However, stresses at the touchdown zone (TDZ), in such configurations are very large in ultra-deep waters for FPSOs in harsh environments leading the solution to become unfeasible in some fields. Therefore, steel lazy-wave risers (SLWR), are the market solutions for those fields. Nonetheless, SLWRs are, normally, longer risers with buoyancy modules, which increases installation time and overall cost. Gimbal Joint Riser (GJR) provides an alternative to reduce stresses at TDZ in SCRs. It is a patented device that comprises a series of hinged connection elements placed around a flexible pipe. This mechanism articulates, absorbing the energy coming from the motion of the hang-off, thus reducing stresses at TDZ. GJR is currently under qualification process. Recently, an experimental campaign involving two small scale models have been concluded. This paper brings a summary of the improvement in the GJR development obtained from these tests. A numerical model has been built to represent the experiments and the results of the calibrated real scale model derived from the experimental outputs are also presented. Results show a significant mitigation in the compressive wave at the TDZ of between 50% to 70% reduction in energy in comparison to SCRs.

The knowledge of micronutrients for Jute (Corchorus capsularis L.) plants might be a valuable tool to the subsidize taking of decisions to the management of such species. The objective of this study was to describe the symptoms of micronutrient deficiencies in jute plants and to analyze micronutrient contents in leaves, stems, and roots. The experiment was carried out in a greenhouse, with six treatments and four replications in a randomized block design. The treatments were, as follows: Complete solution (C) and solution with the omission of the following nutrients: B, Cu, Fe, Mn, and Zn. Except for Cu deficiency, the morphological alterations were easily characterized for all nutrients evaluated, in which Fe and Zn were the first and the last to cause symptoms in plants, respectively. In general, the nutrients that were most limiting to the growth of Jute plant and for dry mass were Fe and B. The omission of B, Mn and Fe limited root growth while the Zn and Cu deficiencies limited the growth of the aerial part. seedings of Jute, the deficiency of Fe and B are the most limiting and the suitable nutritional contents for those seedlings are 11.37; 8.99; 346.14; 248.88 and 77,28 mg.kg -1 for B, Cu, Fe, Mn and Zn in the leaves, respectively.