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This work proposes a new plastic-hardening, non-associative macroelement model to predict the behaviour of anchors in clay for floating offshore structures during keying and up to the peak load. Building on available models for anchors, a non-associated plastic potential is introduced to improve prediction of anchor trajectory and loss of embedment at peak conditions for a large range of padeye offsets and different pull-out directions. The proposed model also includes a displacement-hardening rule to simulate the force and displacement mobilisation at the early stages of the keying process. The model is challenged and validated against different sets of numerical and centrifuge data. This extensive validation process revealed that two of the four newly introduced model parameters assume a constant value for the range of simulated cases. This suggests that only two of the newly introduced parameters may need to be calibrated for the use of the proposed macroelement model in practice. Key words: plate anchor, macro-element model, pull-out resistance, trajectory, floating offshore structures. Ce travail propose un nouveau modele de macro-elements non associatifs a durcissement plastique pour predire le comportement des ancres dans l'argile pour les structures offshore flottantes pendant le calage et jusqu'a la charge de pointe. Sur la base des modeles disponibles pour les ancres, un potentiel plastique non associe est introduit pour ameliorer la prediction de la trajectoire de l'ancre et de la perte d'encastrement dans des conditions de pointe pour une large gamme de decalages de padeye et de differentes directions d'arrachage. Le modele propose comprend egalement une regle de durcissement des deplacements pour simuler la mobilisation des forces et des deplacements aux premiers stades du processus de codage. Le modele est remis en question et valide par rapport a differents ensembles de donnees numeriques et de donnees de centrifugeuse. Ce processus de validation approfondi a revele que deux des quatre parametres du modele nouvellement introduit prennent une valeur constante pour la gamme des cas simules. Cela suggere que seuls deux des parametres nouvellement introduits pourraient devoir etre calibres pour l'utilisation du modele de macro-elements propose dans la pratique. [Traduit par la Redaction] Mots-cles: ancre a plaque, modele de macro-element, resistance a l'arrachement, trajectoire, structures offshore flottantes., 1. Introduction The offshore renewable energy sector is moving towards the installation of floating wind production plants in deeper water sites, as well as pioneering new floating wave energy converter [...]

Available analytical methodologies for the stress analysis of buried pipelines against large permanent ground displacements (PGDs) apply only to straight pipeline segments. Hence, a new methodology is proposed herein for the analytical computation of pipeline strains in bends of arbitrary angle and radius of curvature, located outside the PGD high-curvature zone, but within the pipeline's unanchored length. The methodology is based on the equivalent-linear analysis of the bend, assuming that it will perform as an elastic arched beam subjected to uniformly distributed ultimate axial and transverse horizontal soil reactions. The end of the bend towards the PGD zone is subjected to an axial displacement, calculated on the basis of overall displacement compatibility along the pipeline, while the other end is restrained by the unanchored pipeline segment beyond the bend. Using this approach, the maximum axial force at the vicinity of the PGD zone can also be calculated and consequently used for the estimation of corresponding pipeline strains with any of the available numerical or analytical methodologies for straight pipeline segments. Parametric nonlinear finite element analyses are performed to verify the analytical methodology and also derive conclusions of practical interest regarding the effect of bends on pipeline design. Key words: pipelines, bends, permanent ground displacements, faults, analytical methodology. Les methodes d'analyse disponibles pour l'analyse des contraintes de pipelines enterres contre les grands deplacements de sols permanents (PGDs << permanent ground displacements >>) s'appliquent uniquement a des segments droits de pipeline. Par consequent, une nouvelle methodologie est ici proposee pour le calcul analytique des deformations de pipeline dans les courbures d'angle arbitraire et de rayon de courbure, situe hors de la zone de haute-courbure PGD, mais dans la longueur de pipeline sans ancrage. La methodologie est basee sur l'analyse lineaire equivalente de la courbure, en supposant qu'elle se comportera comme une poutre arquee elastique soumise a des reactions de sol horizontal transversal et axial ultime uniformement reparties. La fin de la courbe vers la zone PGD subit un deplacement axial, calcule sur la base de la coherence globale de deplacement le long du pipeline, tandis que l'autre extremite est retenue par le segment de pipeline sans ancrage au-dela de la courbure. En utilisant cette approche, la force axiale maximale a proximite de la zone PGD peut etre aussi calculee et par consequent utilisee pour l'estimation des deformations de pipeline correspondant avec l'une des methodes analytiques ou numeriques disponibles pour les segments de pipeline droits. Les analyses par elements finis non lineaires parametriques sont effectuees afin de verifier la methodologie analytique et egalement tirer des conclusions d'interet pratique relatif a l'effet de courbure sur la conception du pipeline. [Traduit par la Redaction] Mots-cles: pipelines, courbures, deplacements de sol permanent, failles, methodologie d'analyse., Introduction Permanent ground displacements (PGDs) are probably one of the most critical loading conditions that need to be taken into account in buried pipeline design (ALA-ASCE 2005; O'Rourke and Liu [...]

This work presents a new macro-element model to predict the behaviour of Suction Embedded Plate Anchors (SEPLAs) for floating offshore structures during keying and loading stages. Differently from previously published models for anchors, this new model is characterised by (i) a non-associated plastic potential with the aim of improving the prediction of anchor trajectory for the whole displacement domain and for a large range of padeye offsets; and (ii) by a strain-hardening rule enabling to predict the force and displacement mobilisation from the early stages of the keying process. The model was calibrated against LDFE analyses and compared with a broad set of LDFE and centrifuge tests results. The model proves capable of reproducing anchor rotation and displacement with good accuracy for a wide range of padeye offsets and distinct studies from the literature.

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years there has been renewed interest on integral abutment bridges (IABs), mainly due to their low construction and maintenance cost. Owing to the monolithic connection between deck and abutments, there is strong soil‐structure interaction between the bridge and the backfill under both thermal action and earthquake shaking. Although some of the regions where IABs are adopted qualify as highly seismic, there is limited knowledge as to their dynamic behaviour and vulnerability under strong ground shaking. To develop a better understanding on the seismic behaviour of IABs, an extensive experimental campaign involving over 75 shaking table tests and 4800 time histories of recorded data, was carried out at EQUALS Laboratory, University of Bristol, under the auspices of EU‐sponsored SERA project (Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe). The tests were conducted on a 5 m long shear stack mounted on a 3 m × 3 m 6‐DOF earthquake simulator, focusing on interaction effects between a scaled bridge model, abutments, foundation piles and backfill soil. The study aims at (a) developing new scaling procedures for physical modelling of IABs, (b) investigating experimentally the potential benefits of adding compressible inclusions (CIs) between the abutment and the backfill and (c) exploring the influence of different types of connection between the abutment and the pile foundation. Results indicate that the CI reduces the accelerations on the bridge deck and the settlements in the backfill, while disconnecting piles from the cap decreases bending near the pile head. [ABSTRACT FROM AUTHOR]

A bstract Molecular mechanisms governing maintenance, commitment, and differentiation of stem cells are largely unexploited. Molecules involved in the regulation of multiple cellular processes are of particular importance for stem cell physiology, as they integrate different signals and coordinate cellular decisions related with self-renewal and fate determination. Geminin has emerged as a critical factor in DNA replication and stem cell differentiation in different stem cell populations. Its inhibitory interaction with Cdt1, a member of the prereplicative complex, ensures the controlled timing of DNA replication and, consequently, genomic stability in actively proliferating cells. In embryonic as well as somatic stem cells, Geminin has been shown to interact with transcription factors and epigenetic regulators to drive gene expression programs and ultimately guide cell fate decisions. An ever-growing number of studies suggests that these interactions of Geminin and proteins regulating transcription are conserved among metazoans. Interactions between Geminin and proteins modifying the epigenome, such as members of the repressive Polycomb group and the SWI/SNF proteins of the permissive Trithorax, have long been established. The complexity of these interactions, however, is only just beginning to unravel, revealing key roles on maintaining stem cell self-renewal and fate specification. In this review, we summarize current knowledge and give new perspectives for the role of Geminin on transcriptional and epigenetic regulation, alongside with its regulatory activity in DNA replication and their implication in the regulation of stem and progenitor cell biology. S tem C ells 2017;35:299-310 [ABSTRACT FROM AUTHOR]

Available analytical methodologies for the stress analysis of buried pipelines against large permanent ground displacements (PGDs) apply only to straight pipeline segments. Hence, a new methodology is proposed herein for the analytical computation of pipeline strains in bends of arbitrary angle and radius of curvature, located outside the PGD high-curvature zone, but within the pipeline's unanchored length. The methodology is based on the equivalent-linear analysis of the bend, assuming that it will perform as an elastic arched beam subjected to uniformly distributed ultimate axial and transverse horizontal soil reactions. The end of the bend towards the PGD zone is subjected to an axial displacement, calculated on the basis of overall displacement compatibility along the pipeline, while the other end is restrained by the unanchored pipeline segment beyond the bend. Using this approach, the maximum axial force at the vicinity of the PGD zone can also be calculated and consequently used for the estimation of corresponding pipeline strains with any of the available numerical or analytical methodologies for straight pipeline segments. Parametric nonlinear finite element analyses are performed to verify the analytical methodology and also derive conclusions of practical interest regarding the effect of bends on pipeline design. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cdt1 and its inhibitor Geminin are important regulators of replication licensing. In normal cells, a critical balance between these two proteins ensures that firing of each origin along the genome will take place only once per cell cycle. Cdt1 overexpression in cell lines and animals leads to aberrant replication, activates DNA damage checkpoints and predisposes for malignant transformation. Geminin inactivation mimics the effects of Cdt1 overexpression in cells and generates mitotic defects and abnormal chromosome segregation. Aberrant expression of Cdt1 and Geminin is thus linked to DNA replication defects, aneuploidy and genomic instability. These traits are considered integral to precancerous states and essential elements for malignant transformation. Moreover, Cdt1 and Geminin expression is deregulated in human tumor specimens and Cdt1 and Geminin may represent novel markers useful for cancer diagnosis and prognosis.