Thermogenesis in brown adipocytes, conferred by mitochondrial uncoupling protein 1 (UCP1), is receiving great attention because metabolically active brown adipose tissue may protect humans from ...metabolic diseases. In particular, the thermogenic function of brown‐like adipocytes in white adipose tissue, known as brite (or beige) adipocytes, is currently of prime interest. A valid procedure to quantify the specific contribution of UCP1 to thermogenesis is thus of vital importance. Adrenergic stimulation of lipolysis is a common way to activate UCP1. We here report, however, that in this frequently applied setup, taking control over intracellular fatty acid levels is essential for the analysis of thermogenic function in cultured brown and brite adipocytes. By the application of these findings, we demonstrate that UCP1 is functionally thermogenic in intact brite adipocytes and adrenergic UCP1 activation is largely dependent on adipose triglyceride lipase (ATGL) rather than hormone sensitive lipase (HSL).
Synopsis
This study provides guidelines and protocols for the accurate quantification of the specific contribution of UCP1 to thermogenesis in brown and brite/beige adipocytes.
Activation of UCP1 is a prerequisite for quantifying UCP1‐mediated leak respiration in cultured primary adipocytes
Free fatty acids released by adrenergic‐stimulated lipolysis mask the specific UCP1‐mediated component of uncoupled respiration by inducing unspecific leak respiration in cultured primary adipocytes
Scavenging of free fatty acids with BSA enables specific measurement of UCP1‐mediated uncoupled respiration and reveals thermogenic property of brite adipocytes in a similar fashion as in brown adipocytes, with activation being largely dependent on adipose triglyceride lipase (ATGL).
This study provides guidelines and protocols for the accurate quantification of the specific contribution of UCP1 to thermogenesis in brown and brite/beige adipocytes.
•Proposal for full-field residual stress identification procedure from partially measured and corrupted measurement without eigenstrain information.•A mixed finite element approach, of ...Hellinger-Reissner type, is proposed within an inverse problem framework.•An energy based penalized least square approach is adopted to solve optimization problem.•Non-iterative reconstruction procedure is validated against a few problems of engineering interest.
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In this paper a full-field residual stress identification procedure is proposed and explored from partially measured residual elastic strain or stress within a PDE constrained optimization framework. At first, we have constructed a penalized least-square cost functional with an appropriate regularization term. We have taken data discrepancy term in energy norm while the regularization term is a complementary strain energy functional. We then construct an appropriate Lagrangian to impose the optimization constraint. It turns out that using first order optimality condition leads to standard two field mixed, of Hellinger-Reissner type, variational formulation with residual stress and Lagrangian variable as independent field variables. This allows us to use standard two and three dimensional mixed finite elements for approximation of the stress and Lagrangian variable. Using mixed finite element set-up, we then solved these equations to obtain full-field residual stress distribution. One key issue of the proposed formulation, as in case of any inverse problem, is the choice of penalization parameter. In this context, we have used modified L-curve based approach to choose optimal penalty parameter. Finally, we assess the numerical effectiveness of the proposed procedure against a few problems of engineering interest.
In the offshore oil production industry, information regarding the actual configuration of the mooring lines and risers of floating production systems (FPS) is periodically collected from field ...observations and surveys using remotely operated vehicles (ROVs). Taking advantage of such information, this work presents a retroanalysis procedure that updates and calibrates numerical models to represent the updated as-laid configuration of the FPS. This procedure has been implemented in association with the in-house, non-commercial SITUA-Prosim software that employs uncoupled, fully coupled and hybrid analysis formulations. The steps of the procedure are automated within the software. The application of the procedure is illustrated in a case study considering a typical FPS representative of actual offshore scenarios. This retroanalysis procedure may be seen as the first stage for the development of a digital twin for FPS, and for the establishment of an integrity assessment methodology using the updated as-laid models. The integrity of the system can be continuously reassessed by performing a series of analyses to check whether the appropriate design criteria of mooring lines and risers are still being met.
•Retroanalysis procedure evolved from actual operational practice.•Generates numerical models to represent updated as-laid configuration of an FPS.•The steps of the procedure are automated within a specialized computational tool.•First stage of a digital twin for floating production systems.•Provides relevant and updated information regarding the behavior of the FPS.
Incomplete multiview clustering (IMC) methods have achieved remarkable progress by exploring the complementary information and consensus representation of incomplete multiview data. However, to our ...best knowledge, none of the existing methods attempts to handle the uncoupled and incomplete data simultaneously, which affects their generalization ability in real-world scenarios. For uncoupled incomplete data, the unclear and partial cross-view correlation introduces the difficulty to explore the complementary information between views, which results in the unpromising clustering performance for the existing multiview clustering methods. Besides, the presence of hyperparameters limits their applications. To fill these gaps, a novel uncoupled IMC (UIMC) method is proposed in this article. Specifically, UIMC develops a joint framework for feature inferring and recoupling. The high-order correlations of all views are explored by performing a tensor singular value decomposition (t-SVD)-based tensor nuclear norm (TNN) on recoupled and inferred self-representation matrices. Moreover, all hyperparameters of the UIMC method are updated in an exploratory manner. Extensive experiments on six widely used real-world datasets have confirmed the superiority of the proposed method in handling the uncoupled incomplete multiview data compared with the state-of-the-art methods.
Fracture constantly occurs during the plastic forming processes of thin-walled metal sheets due to the local uneven plastic deformation. During the processes, the sheets may experience different ...stress states, which are crucial factors related to the fracture. To predict fracture in different forming processes, various uncoupled ductile fracture criteria have been proposed due to their advantages of relatively simple expressions and less modeling parameters. Because each fracture criterion focusses on certain aspects of the deformation behavior, the ability of fracture prediction can be dramatically different. Thus, a systematical study on eight widely applied uncoupled ductile fracture criteria is carried out to evaluate their applicability under four different stress states, i.e. pure shear, dog-bone tensile, notched tensile and hydraulic bulging. Each criterion is numerically implemented and embedded into finite element models and is applied for fracture prediction of an anisotropic aluminum alloy sheet. The prediction results are compared to experimental results and the applicability of each criterion is analyzed.
Adipocytes, once considered simple lipid-storing cells, are rapidly emerging as complex cells with many biologically diverse functions. A powerful high-throughput method for analyzing single cells is ...flow cytometry. Several groups have attempted to analyze and sort freshly isolated adipocytes; however, using an adipocyte-specific reporter mouse, we demonstrate that these studies fail to detect the majority of white adipocytes. We define critical settings required for adipocyte flow cytometry and provide a rigid strategy for analyzing and sorting white and brown adipocyte populations. The applicability of our protocol is shown by sorting mouse adipocytes based on size or UCP1 expression and demonstrating that a subset of human adipocytes lacks the β2-adrenergic receptor, particularly in the insulin-resistant state. In conclusion, the present study confers key technological insights for analyzing and sorting mature adipocytes, opening up numerous downstream research applications.
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•Protocol to sort freshly isolated adipocytes based on size or UCP1 expression•Previously described methods fail to detect the majority of white adipocytes•A subset of human adipocytes lacks the β2-adrenergic receptor
Freshly isolated adipocytes are a notoriously difficult cell type to study. Hagberg et al. provide a detailed flow cytometry protocol for the analysis and sorting of mouse and human adipocytes by defining the critical factors and conditions required for studying this specialized cell type and pinpointing common pitfalls.
Abstract
To analyze the influence of radial decoupling parameters on the blasting effect of limestone, finite element analysis was established using ANSYS/ls-dyna to analyze the effects of different ...radial decoupling coefficients and different media on blasting. Research has found that limestone has more cracks and more pronounced cracking when air is uncoupled. Under the condition of air decoupling, the stress waves in the rock mass are more concentrated and have higher energy, while under the condition of water decoupling, the stress waves in the rock mass diffuse faster, have a larger range of action, and have lower energy. Reasonably increasing the radial decoupling coefficient can effectively reduce damage around the borehole. For limestone formations, it is recommended to use an air decoupling method during construction, with a radial decoupling coefficient kd=2.0 for the borehole.
The exercise recommendation system is emerging as a promising application in online learning scenarios, providing personalized recommendations to assist students with explicit learning directions. ...Existing solutions generally follow a collaborative filtering paradigm, while the implicit connections between students (exercises) have been largely ignored. In this study, we aim to propose an exercise recommendation paradigm that can reveal the latent connections between student-student (exercise-exercise). Specifically, a new framework was proposed, namely personalized exercise recommendation with student and exercise portraits (PERP). It consists of three sequential and interdependent modules: Collaborative student exercise graph (CSEG) construction, joint random walk, and recommendation list optimization. Technically, CSEG is created as a unified heterogeneous graph with students’ response behaviors and student (exercise) relationships. Then, a joint random walk to take full advantage of the spectral properties of nearly uncoupled Markov chains is performed on CSEG, which allows for full exploration of both similar exercises that students have finished and connections between students (exercises) with similar portraits. Finally, we propose to optimize the recommendation list to obtain different exercise suggestions. After analyses of two public datasets, the results demonstrated that PERP can satisfy novelty, accuracy, and diversity.
This work describes an integrity assessment methodology that considers field monitoring and inspection activities that gather information regarding the actual configuration of the mooring lines and ...risers of floating production systems (FPS). The first stage consists of calibrating numerical models representing the updated as-laid configuration, comprising “digital twins” of the FPS. Then, in the remaining stages, these models are employed to perform a series of uncoupled, hybrid and fully coupled analyses that provide the platform offsets, and the structural response of the mooring lines and risers. These are expressed in terms of offset diagrams (polar diagrams comprised by the envelope of maximum platform excursions); and the safe operational zone (SAFOP) for the risers (polar diagrams defining the envelope of safe horizontal excursions within which the riser top connections must remain to avoid violation of any riser design criterion). The integrity is assessed by comparing the SAFOP and offset diagrams, and comparing the maximum mooring line tensions with their corresponding limit values. Mitigation and contingency procedures are then recommended whenever the integrity of one or more mooring lines or risers is compromised, involving redesign steps and field interventions to adjust the as-laid configuration and return the system to a safe operational condition.
•Considers field monitoring and inspection activities of Floating Production Systems.•“Digital twin” numerical models represent updated as-laid configuration.•Models are employed to provide platform offsets and mooring line/riser responses.•Integrity assessed by comparing offset diagrams, riser SAFOP, and mooring line tensions.•Mitigation/contingency procedures may be recommended: increased safety and reduced costs.
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