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• A multi-mode fusion method is proposed to predict the motion of platform. • The signals are decomposed into approximately stationary signals by VMD method. • The proposed method achieves high precision real-time prediction. To address poor prediction accuracy caused by signal fluctuation, randomness, and noise interference in motion response prediction for floating platforms, a method combining Variational Modal Decomposition (VMD) and multi-model fusion is proposed. Initially, raw data undergoes VMD preprocessing, yielding Intrinsic Modal Functions (IMFs). These IMFs, along with ocean environmental data, are utilized in Long Short-Term Memory (LSTM), Bi-Directional Long Short-Term Memory (BiLSTM), and Gated Recurrent Units (GRU) models. Subsequently, Bayesian Linear Regression (BLR) is applied to the combined prediction results and original features for final prediction. Experimental results demonstrate superior stability and accuracy compared to other model prediction methods, validating the proposed approach's efficacy and feasibility in tackling prediction challenges. [ABSTRACT FROM AUTHOR]

As a key equipment in deep-sea drilling and production operations, the riser tensioner provides a nearly constant tensioner for the riser to overcome the influence of the floating platform on the riser when it is makingheave motion with the waves. In the harsh deep-water area, when the tethers of Tension Leg Platform (TLP) failure, the Top Tensioned Risers (TTRs) will jump, resulting in the migration of the riser resonance region, which will cause the parametric resonance and interference phenomenon of the riser. Therefore, based on Adams and AMESim co-simulation, this paper calculates the dynamic characteristics of the displacement tension of the tensioner system on the traditional TLP under tether failure. Based on the dynamic characteristics of the tensioner system, a synchronous control strategy of the displacement tension of the tensioner under tether failure is proposed. The strategy uses the opening of the anti-recoil valve to realize the stable recovery of the riser and adjusts the output tension of the tensioner in the recoil process of the riser through the proportional relief valve. Compared with the traditional control method and non-control method, the effectiveness of this strategy is verified. The results show that the designed displacement tension synchronization control strategy can provide more stable tension for the riser, and the displacement amplitude of the hydraulic cylinder is smaller, which can realize the stable recovery of the riser. Moreover, it is found in many simulations that the opening of the main valve and the displacement curve of the hydraulic cylinder mainly affect the retraction speed of the hydraulic cylinder, and the maximum opening pressure of the proportional relief valve affects the output tension of the tensioner system. • The dynamic characteristics of the tensioner is simulated when the tendon of TLP fails instantaneously. • A hydraulic control system is designed to overcome the influence of a platform on risers. • A double-cavity synchronous control method is adopted for the hydraulic cylinder to realize the compensation control. • Dynamic responses of the cylinders in the anti-recoil control process considering the second-order wave force are simulated. [ABSTRACT FROM AUTHOR]

Biochemicals are widely used in the medicine and food industries and are more efficient and safer than synthetic chemicals. The amphipathic surfactants can interact with the microorganisms and embed the extracellular metabolites, which induce microbial metabolites secretion and biosynthesis, performing an attractive prospect of promoting the biochemical production. However, the commonness and differences of surfactant-mediated bio-manufacture in various fields are largely unexplored. Accordingly, this review comprehensively summarized the properties of surfactants, different application scenarios of surfactant-meditated bio-manufacture, and the mechanism of surfactants increasing metabolites production. Various biochemical productions such as pigments, amino acids, and alcohols could be enhanced using the cloud point and the micelles of surfactants. Besides, the amphiphilicity of surfactants also promoted the utilization of fermentation substrates, especially lignocellulose and waste sludge, by microorganisms, indirectly increasing the metabolites production. The increase in target metabolites production was attributed to the surfactants changing the permeability and composition of the cell membrane, hence improving the secretion ability of microorganisms. Moreover, surfactants could regulate the energy metabolism, the redox state and metabolic flow in microorganisms, which induced target metabolites synthesis. This review aimed to broaden the application fields of surfactants and provide novel insights into the production of microbial biochemicals. [ABSTRACT FROM AUTHOR]

Synthetic multicellular (MC) systems have the capacity to increase our understanding of biofilms and higher organisms, and to serve as engineering platforms for developing complex products in the areas of medicine, biosynthesis and smart materials. Here we provide an interdisciplinary perspective and review on emerging approaches to engineer and model MC systems. We lay out definitions for key terms in the field and identify toolboxes of standardized parts which can be combined into various MC algorithms to achieve specific outcomes. Many essential parts and algorithms have been demonstrated in some form. As key next milestones for the field, we foresee the improvement of these parts and their adaptation to more biological systems, the demonstration of more complex algorithms, the advancement of quantitative modeling approaches and compilers to support rational MC engineering, and implementation of MC engineering for practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Increasing evidence indicates that the progression of calcific aortic valve disease (CAVD) is influenced by the mechanical forces experienced by valvular interstitial cells (VICs) embedded within the valve matrix. The ability of VICs to sense and respond to tissue-level mechanical stimuli depends in part on cellular-level biomechanical properties, which may change with disease. In this study, we used micropipette aspiration to measure the instantaneous elastic modulus of normal VICs and of VICs induced to undergo pathological differentiation in vitro to osteoblast or myofibroblast lineages on compliant and stiff collagen gels, respectively. We found that VIC elastic modulus increased after subculturing on stiff tissue culture-treated polystyrene and with pathological differentiation on the collagen gels. Fibroblast, osteoblast, and myofibroblast VICs had distinct cellular-level elastic properties that were not fully explained by substrate stiffness, but were correlated with α-smooth muscle actin expression levels. C-type natriuretic peptide, a peptide expressed in aortic valves in vivo, prevented VIC stiffening in vitro, consistent with its ability to inhibit α-smooth muscle actin expression and VIC pathological differentiation. These data demonstrate that VIC phenotypic plasticity and mechanical adaptability are linked and regulated both biomechanically and biochemically, with the potential to influence the progression of CAVD. [Copyright &y& Elsevier]