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This retrospective aims to present a coherent history of important findings in direct numerical simulations and experiments in turbulent Taylor-Couette (TC) flow of dilute polymeric solutions in the last decade. Specifically, the sequence of flow transitions due to a continuous increase of fluid elasticity from classical Newtonian, to inertially and in turn to elastically dominated, and finally to the inertialess purely elastic turbulence, is presented. In each elastically modified flow state, the drag modification, coherent flow structures, velocity and elastic stress statistics, mechanism of turbulent kinetic energy production, spectral features as well as the self-sustaining cycles of turbulence, are discussed. Finally, to provide a broader perspective, an overview of important similarities and differences between elastically induced turbulence in prototypical curvilinear and rectilinear shear flows including the curvature-free limit of TC flow, namely, the spanwise-rotating plane Couette flow, is presented. [ABSTRACT FROM AUTHOR]

The tumor promoter 12-O-tetra-decanoylphorbol-13-acetate (TPA) has been defined by its ability to promote tumorigenesis on carcinogen-initiated mouse skin. Activation of Wnt/β-catenin signaling has a decisive role in mouse skin carcinogenesis, but it remains unclear how TPA activates Wnt/β-catenin signaling in mouse skin carcinogenesis. Here, we found that TPA could enhance Wnt/β-catenin signaling in a casein kinase 1 (CK1) ε/δ-dependent manner. TPA stabilized CK1ε and enhanced its kinase activity. TPA further induced the phosphorylation of LRP6 at Thr1479 and Ser1490 and the formation of a CK1ε-LRP6-axin1 complex, leading to an increase in cytosolic β-catenin. Moreover, TPA increased the association of β-catenin with TCF4E in a CK1ε/δ-dependent way, resulting in the activation of Wnt target genes. Consistently, treatment with a selective CK1ε/δ inhibitor SR3029 suppressed TPA-induced skin tumor formation in vivo, probably through blocking Wnt/β-catenin signaling. Taken together, our study has identified a pathway by which TPA activates Wnt/β-catenin signaling. [ABSTRACT FROM AUTHOR]

Cloud computing attracted more and more attention in recent years, and virtualization technology is the key point for deploying infrastructure services in cloud environment. It allows application isolation and facilitates server consolidation, load balancing, fault management, and power saving. Live virtual machine migration can effectively relocate virtual resources and it has become an important management method in clusters and data centers. Existing precopy live migration approach has to iteratively copy redundantmemory pages; another postcopy livemigration approach would lead to a lot of page faults and application degradation. In this paper, we present a novel approach called TSMC (three-stage memory copy) for live virtual machine migration. In TSMC, memory pages only need to be transmitted twice at most and page fault just occurred in small part of dirty pages. We implement it in Xen and compare it with Xen's original precopy approach. The experimental results under various memory workloads show that TSMC approach can significantly reduce the cumulative migration time and total pages transferred and achieve better network IO performance in the same time. [ABSTRACT FROM AUTHOR]

Juglans mandshurica is a precious timber and economic tree species in Northeast China. Because of the reproductive characteristics of this species, such as long childhood and dioecious, the flowering period of male and female flowers is different, which directly affects the sexual reproduction process such as flowering and pollination. At present, the molecular mechanism of dioecious flowering of J. mandshurica is not clear. In this study, the cDNA sequence of a crucial gene involved in plant flowering, LEAFY (LFY) was cloned from J. mandshurica by homologous cloning, and the expression in different organs at various developmental stages, and the subcellular localization of the gene were analyzed. LFY in J. mandshurica was found to possess high homology (over 79%), and a similar structure and function to LFY in other species, and was cloned and named JmLFY (GenBank: KX364241). The results of fluorescence quantitative real-time PCR analysis revealed that JmLFY was expressed in different organs, and that expression increased significantly before the early development stage of staminate inflorescence, the anther formation and pollen dispersal stage, pistillate inflorescence sprouting and flower development stage, and the pollination and late stage of zygotic embryo development. Expression of the green fluorescent protein fusion JmLFY gene in onion epidermal cells was localized to the nucleus and cytoplasm. Our results indicate that the JmLFY gene is the key transcription factor involved in flower formation and development in J. mandshurica. These findings provide information that may help to overcome the bottleneck caused by the long juvenile period and asynchronous female and male flowers of the species in the future. [ABSTRACT FROM AUTHOR]

Importance: For patients with large vessel occlusion strokes, it is unknown whether endovascular treatment alone compared with intravenous thrombolysis plus endovascular treatment (standard treatment) can achieve similar functional outcomes.Objective: To investigate whether endovascular thrombectomy alone is noninferior to intravenous alteplase followed by endovascular thrombectomy for achieving functional independence at 90 days among patients with large vessel occlusion stroke.Design, Setting, and Participants: Multicenter, randomized, noninferiority trial conducted at 33 stroke centers in China. Patients (n = 234) were 18 years or older with proximal anterior circulation intracranial occlusion strokes within 4.5 hours from symptoms onset and eligible for intravenous thrombolysis. Enrollment took place from May 20, 2018, to May 2, 2020. Patients were enrolled and followed up for 90 days (final follow-up was July 22, 2020).Interventions: A total of 116 patients were randomized to the endovascular thrombectomy alone group and 118 patients to combined intravenous thrombolysis and endovascular thrombectomy group.Main Outcomes and Measures: The primary end point was the proportion of patients achieving functional independence at 90 days (defined as score 0-2 on the modified Rankin Scale; range, 0 [no symptoms] to 6 [death]). The noninferiority margin was -10%. Safety outcomes included the incidence of symptomatic intracerebral hemorrhage within 48 hours and 90-day mortality.Results: The trial was stopped early because of efficacy when 234 of a planned 970 patients had undergone randomization. All 234 patients who were randomized (mean age, 68 years; 102 women [43.6%]) completed the trial. At the 90-day follow-up, 63 patients (54.3%) in the endovascular thrombectomy alone group vs 55 (46.6%) in the combined treatment group achieved functional independence at the 90-day follow-up (difference, 7.7%, 1-sided 97.5% CI, -5.1% to ∞)P for noninferiority = .003). No significant between-group differences were detected in symptomatic intracerebral hemorrhage (6.1% vs 6.8%; difference, -0.8%; 95% CI, -7.1% to 5.6%) and 90-day mortality (17.2% vs 17.8%; difference, -0.5%; 95% CI, -10.3% to 9.2%).Conclusions and Relevance: Among patients with ischemic stroke due to proximal anterior circulation occlusion within 4.5 hours from onset, endovascular treatment alone, compared with intravenous alteplase plus endovascular treatment, met the prespecified statistical threshold for noninferiority for the outcome of 90-day functional independence. These findings should be interpreted in the context of the clinical acceptability of the selected noninferiority threshold.Trial Registration: Chinese Clinical Trial Registry: ChiCTR-IOR-17013568. [ABSTRACT FROM AUTHOR]

Based on POC set theory and SOC unit, a 1T3R parallel stable platform is proposed. Topology structure design of low-DOF parallel stable platform is studied. Both inverse and direct kinematics and Jacobean matrix of this mechanism are analyzed. Based on the structure of the whole platform, a three-dimensional solid model is established with Pro/Engineer software, and kinematics simulation analysis is performed in ADAMS. It establishes base for the application of this kind of parallel stable platform and the follow-up research for analysis of kinematics and workspace. The results of this study on the stability of the institutional platform have an important significance. [ABSTRACT FROM AUTHOR]

Prodigiosin, a natural red pigment produced by numerous bacterial species, has exhibited promising anticancer activity; however, the molecular mechanisms of action of prodigiosin on malignant cells remain unclear. Aberrant activation of the Wnt/β-catenin signaling cascade is associated with numerous human cancers. In this study, we identified prodigiosin as a potent inhibitor of the Wnt/ β-catenin pathway. Prodigiosin blocked Wnt/β-catenin signaling by targeting multiple sites of this pathway, including the lowdensity lipoprotein-receptor-related protein (LRP) 6, Dishevelled (DVL), and glycogen synthase kinase-3β (GSK3β). In breast cancer MDA-MB-231 and MDA-MB-468 cells, nanomolar concentrations of prodigiosin decreased phosphorylation of LRP6, DVL2, and GSK3β and suppressed β-catenin-stimulated Wnt target gene expression, including expression of cyclin D1. In MDA-MB-231 breast cancer xenografts andMMTV-Wnt1 transgenic mice, administration of prodigiosin slowed tumor progression and reduced the expression of phosphorylated LRP6, phosphorylated and unphosphorylated DVL2, Ser9 phosphorylated GSK3β, active β-catenin, and cyclin D1. Through its ability to inhibit Wnt/β-catenin signaling and reduce cyclin D1 levels, prodigiosin could have therapeutic activity in advanced breast cancers. [ABSTRACT FROM AUTHOR]