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Microproteins (MPs) are a potentially rich source of uncharacterized metabolic regulators. Here, we use ribosome profiling (Ribo-seq) to curate 3,877 unannotated MP-encoding small ORFs (smORFs) in primary brown, white, and beige mouse adipocytes. Of these, we validated 85 MPs by proteomics, including 33 circulating MPs in mouse plasma. Analyses of MP-encoding mRNAs under different physiological conditions (high-fat diet) revealed that numerous MPs are regulated in adipose tissue in vivo and are co-expressed with established metabolic genes. Furthermore, Ribo-seq provided evidence for the translation of Gm8773, which encodes a secreted MP that is homologous to human and chicken FAM237B. Gm8773 is highly expressed in the arcuate nucleus of the hypothalamus, and intracerebroventricular administration of recombinant mFAM237B showed orexigenic activity in obese mice. Together, these data highlight the value of this adipocyte MP database in identifying MPs with roles in fundamental metabolic and physiological processes such as feeding.

The use of ground source heat pumps to transfer heat to and from the ground via borehole heat exchangers (BHEs) is among the most energy efficient techniques for space heating and cooling. Broader applications in urban environments require more careful evaluation of hydro-mechanical behavior of soil to ensure their reliable long-term performance and to minimize adverse effects on adjacent structures. An advanced soil model has been integrated within a finite difference (FD) framework, to solve coupled thermo-hydro-mechanical (THM) problems in an axisymmetric space. The FD simulator is applied to a prototype project and the ground conditions represent typical stress history profiles found in Geneva, Switzerland. An extensive parametric study is undertaken to study the long-term THM response of clay for a broad range of heat exchanger design parameters. The results show that significant settlements can be induced due to the long-term operation of BHEs (i.e., over periods from 10 to 50 years). The parametric study gives useful guidelines for heat exchanger design and identifies a design space of optimum solutions that meet pre-specified foundation settlement criteria. The study provides a qualitative investigation and a systematic framework for analyzing the long-term THM response of clay to seasonal heating and cooling. Key words: ground heat exchangers, ground source heat pumps, finite difference methods, constitutive modeling, parametric study. L'utilisation de pompes geothermiques pour transferer la chaleur vers et depuis le sol via des echangeurs de chaleur de forage (BHE) est l'une des techniques les plus efficaces sur le plan energetique pour le chauffage et le refroidissement des locaux. Des applications plus larges en milieu urbain necessitent une evaluation plus minutieuse du comportement hydro-mecanique des sols afin de garantir leur performance fiable a long terme et de minimiser les effets negatifs sur les structures adjacentes. Un modele de sol avance a ete integre dans un cadre des differences finies (FD), pour resoudre les problemes thermo-hydro-mecaniques (THM) couples dans un espace axisymetrique. Le simulateur FD est applique a un projet prototype et les conditions du sol representent les profils typiques des contraintes deja subies que l'on trouve a Geneve, en Suisse. Une etude parametrique approfondie est entreprise pour etudier la reponse THM a long terme de l'argile pour un large eventail de parametres de conception des echangeurs de chaleur. Les resultats montrent que des tassements importants peuvent etre induits en raison du fonctionnement a long terme des BHE (c'est-a-dire sur des periodes allant de 10 a 50 ans). L'etude parametrique donne des directives utiles pour la conception des echangeurs de chaleur et identifie un espace de conception de solutions optimales qui repondent a des criteres predefinis d'implantation des fondations. L'etude fournit une investigation qualitative et un cadre systematique pour analyser la reponse THM a long terme de l'argile au chauffage et au refroidissement saisonniers. [Traduit par la Redaction] Mots-cles : echangeurs de chaleur geothermiques, pompes geothermiques, methodes des differences finies, modelisation constitutive, etude parametrique., 1. Introduction The use of ground source heat pumps (GSHPs) to transfer heat to and from the ground is among the most energy efficient techniques for space heating and cooling. [...]

This document is a closure to a previous paper titled "Effects of Movement Induced by Ground Improvement on the Performance of an Excavation Support System in Underconsolidated Clay." The closure addresses comments and requests for additional information made by a discusser. The closure provides construction information, including the layout of ground improvement works and the installation of deep soil mix columns and jet grout piles. It also discusses the selection of jet grout pressures, undrained shear strength properties of marine clays, and field performance observations. The closure concludes by addressing the limitations of the numerical modeling used in the original paper. [Extracted from the article]

Climate change and sea‐level rise (SLR) are expected to increase the frequency and intensity of coastal flood events, posing risks to coastal communities and infrastructure. While regional climate adaptation investments can provide substantive flood protection, existing plans often neglect uncertainty in future climate conditions and adaptation performance, consequently neglecting the option value of flexibly implementing proposed projects. Addressing this gap, we develop and employ a generalizable real options analysis (ROA) valuation framework that considers how uncertainty in adaptation project costs, SLR, flood severity, and flood losses inform the full range of adaptation performance outcomes. We further propose and apply a novel, computationally efficient flood loss sampling algorithm to estimate the consequences of randomly arriving coastal flood events. We apply this ROA framework to assess the option value of flexibly timing adaptation investments over time, investigating an adaptation pathway proposed by the City of Boston from the perspective of the regional transit system manager. Our results suggest that flexible implementation can provide significant option value in the near‐ to mid‐term (>30 years), with the highest option values under low‐probability, high‐consequence scenarios. Our results also suggest adaptation pathway performance in the latter half of the 21st century is most sensitive to uncertainty in SLR, flood loss estimates, and flood frequency, underscoring the importance of uncertainty quantification in the long‐term valuation of adaptation investments. [ABSTRACT FROM AUTHOR]

The recent construction of an underground mass rapid transit (MRT) station in Singapore involved 21 m deep excavations within underconsolidated marine clay. The lateral earth support system comprised 1 m thick diaphragm walls socketed into the underlying Old Alluvium and 4 levels of preloaded cross-lot struts. Deep soil mixing (DSM) and jet grouting piles (JGP) were used to improve up to 15 m thickness of the marine clay formation. Field monitoring data showed that these ground improvement processes caused large outward deflections of the diaphragm wall panels at some locations prior to the excavation and may have caused yielding within the wall panels. In this paper, the impacts of these prior wall deformations on the subsequent performance of the excavation support system are investigated. The measured performance at two indicative cross sections is compared with results from simplified 2D finite element analyses. The analyses simulate the effects of ground improvement through prescribed boundary pressures and represent the yielding of the diaphragm wall panels through zones of reduced bending stiffness. We show that large outward wall deflections and curvature observed during jet grouting at one section contribute to higher inward wall movements and strut loads measured during excavation, while smaller movements (and curvature) prior to excavation at a second similar cross section cause negligible change in the performance of the temporary earth retaining system. The results highlight (1) the importance of controlling ground movements associated with ground modification processes such as jet grouting, (2) the uncertainties in estimating mechanical properties for the improved soil mass, and (3) the need to improve the representation of non-linear, flexural properties (M-κ) of reinforced concrete diaphragm panels. [ABSTRACT FROM AUTHOR]

The ground response during diaphragm wall panel installation is strongly affected by the support slurry pressure, and by the subsequent lateral pressures during the tremie placement and set-up of wet concrete. The support slurry pressure can be reliably assumed as hydrostatic within the excavated trench, whereas the lateral concreting pressure is much more complex due to the stiffening effect of wet concrete. This paper reviews the measurements of wet concrete pressures from a series of instrumented diaphragm wall panels which show that lateral pressures in the concrete slurry increase as the tremie displaces bentonite slurry and reach a maximum condition about 1 h after placement, while conditions over the longer term closely approximate the hydrostatic pressure of the bentonite-filled trench. The maximum increase of pressure varies at different heights of the same trench, and also varies for two separate panels in the same project, reflecting the varying velocity of concreting. Model tests of concreting pressure on formwork also demonstrate that the lateral pressure reduces from hydrostatic wet concrete pressure a few hours after casting. A time-dependent lateral concreting pressure model is developed to represent these measurements more realistically. This proposed model is implemented into a finite-element program to investigate its effects on the ground response due to the concreting process. Computed results from a reference case can capture the progressive variations of ground movement, earth and pore water pressure in the soil adjacent to the trench during and shortly after the concreting process, which is consistent with the reported measurements. [ABSTRACT FROM AUTHOR]