49 research outputs found
Reservoir Sediment Management Using Replenishment : A Numerical Study Of Nunome Dam
Improving the integration of dams in the natural environment and recovering their storage capacity lost to sedimentation are two topics of growing concern. To address these two issues, the accumulated sediments are being relocated down into the dam's tail water. This process is called sediment replenishment (SR), and has been tested in Japan and other parts of the world. More study is required to enhance its effectiveness, and the present research thus offers a practical method to assess positive outcomes of SR on the downstream ecosystems. It is shown through a 2-D numerical model of Nunome River that SR positively influences the river's morphology by generating riffle-pool structures and sand bars. These patterns increase the channel's global heterogeneity, and create hydraulically favorable habitats for fish and spawning. The habitat quality was quantified by applying suitability indexes to the computed hydraulic variables, and the SR-induced geomorphologies were designed according to field observations of past SR tests and validated by the 2-D mode
Overexpression of the p73 gene is a novel finding in high-risk B-cell chronic lymphocytic leukemia
The p73 protein shares structural and functional similarities with the tumour-suppressor p53, but its role in neoplastic transformation is unknown. Alternative splicing leads to the expression of at least nine p73 C-terminal mRNA splice variants (α β γ δ ε ξ η ηl θ). In this survey, we analyse the expression of p73 by real-time quantitative RT-PCR, its known C-terminal variants with an RT-PCR-Southern tech nique and by Western blot in samples of 51 patients with B-CLL, normal B lymphocytes from eight individuals, and five haematopoetic cell lines. p73α protein expression positively correlated with higher risk B-CLL stages (P=0.046). Total p73 mRNA expression was higher (P= 0.01) and p73α protein more frequently detected (P=0.008) in B-CLL compared with normal CD19+—B-lymphocytes. p73 C-terminal mRNA variants were expressed both in B-CLL and in normal B-lymphocytes, but their expression was biased since the γ (P=0.041), the θ (P ≪ 0.001), and the η variant (P=0.033) prevailed in normal B-lymphocytes. In summary, we conclude that the accumulation of p73, the expression pattern of particular p73 variants and its link to progression may play a distinct role in the molecular pathology B-CL
A complexity approach to defining urban energy systems
Urban energy systems have been commonly considered to be socio-technical systems within the boundaries of an urban area. However, recent literature challenges this notion in that it urges researchers to look at the wider interactions and influences of urban energy systems wherein the socio-technical sphere is expanded to political, environmental and economic realms as well. In addition to the inter-sectoral linkages, the diverse agents and multilevel governance trends of energy sustainability in the dynamic environment of cities make the urban energy landscape a complex one. There is a strong case then for establishing a new conceptualisation of urban energy systems that builds upon these contemporary understandings of such systems. We argue that the complex systems approach can be suitable for this. In this paper, we propose a pilot framework for understanding urban energy systems using complex systems theory as an integrating plane. We review the multiple streams of urban energy literature to identify the contemporary discussions and construct this framework that can serve as a common ontological understanding for the different scholarships studying urban energy systems. We conclude the paper by highlighting the ways in which the framework can serve some of the relevant communities
Gene trapping identifies chloride channel 4 as a novel inducer of colon cancer cell migration, invasion and metastases
Essential Role of TGF-β/Smad Pathway on Statin Dependent Vascular Smooth Muscle Cell Regulation
BACKGROUND: The 3-hydroxy-3-methylglutaryl CoA reductase inhibitors (also called statins) exert proven beneficial effects on cardiovascular diseases. Recent data suggest a protective role for Transforming Growth Factor-beta (TGF-beta) in atherosclerosis by regulating the balance between inflammation and extracellular matrix accumulation. However, there are no studies about the effect of statins on TGF-beta/Smad pathway in atherosclerosis and vascular cells. METHODOLOGY: In cultured vascular smooth muscle cells (VSMCs) statins enhanced Smad pathway activation caused by TGF-beta. In addition, statins upregulated TGF-beta receptor type II (TRII), and increased TGF-beta synthesis and TGF-beta/Smad-dependent actions. In this sense, statins, through Smad activation, render VSMCs more susceptible to TGF-beta induced apoptosis and increased TGF-beta-mediated ECM production. It is well documented that high doses of statins induce apoptosis in cultured VSMC in the presence of serum; however the precise mechanism of this effect remains to be elucidated. We have found that statins-induced apoptosis was mediated by TGF-beta/Smad pathway. Finally, we have described that RhoA inhibition is a common intracellular mechanisms involved in statins effects. The in vivo relevance of these findings was assessed in an experimental model of atherosclerosis in apolipoprotein E deficient mice: Treatment with Atorvastatin increased Smad3 phosphorylation and TRII overexpression, associated to elevated ECM deposition in the VSMCs within atheroma plaques, while apoptosis was not detected. CONCLUSIONS: Statins enhance TGF-beta/Smad pathway, regulating ligand levels, receptor, main signaling pathway and cellular responses of VSMC, including apoptosis and ECM accumulation. Our findings show that TGF-beta/Smad pathway is essential for statins-dependent actions in VSMCs
The tetraspanin CD9 controls migration and proliferation of parietal epithelial cells and glomerular disease progression
International audienc
Fire safety engineering analysis of a super market structure composed of cambered cellular beams
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