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61.
The role of trust in restoration success: public engagement and temporal and spatial scale in a complex social‐ecological system 下载免费PDF全文
Elizabeth Covelli Metcalf Jakki J. Mohr Laurie Yung Peter Metcalf David Craig 《Restoration Ecology》2015,23(3):315-324
The social dimensions of river restoration are not well understood especially in the context of large‐scale restoration projects embedded in a complex social‐ecological system. This study used in‐depth interviews with diverse stakeholders to examine perceptions of restoration success on the Clark Fork River Superfund project in Western Montana. Trust emerged as critical to restoration success and was influenced by public engagement, and by spatial and temporal scale. At this large scale, multiple relationships between agencies, NGOs, businesses, landowners, and other stakeholders meant that building trust was a complicated endeavor. The large spatial scale and long time frame made public engagement challenging, and landowners in particular were critical of the project, expressing mistrust in both agencies and the project as a whole. However, projects focused on smaller spatial scales, such as particular stream reaches, appeared to inspire more effective collaboration. Relationships between organizations were important at this large scale, but inter‐organizational conflict affected trust across the project. Further, because trust requires accepting vulnerability, recognizing the differential vulnerability that particular groups and communities experience, based on the risks and benefits they accrue relative to the project, is important. 相似文献
62.
Thomas M Huang WS Wen D Zhu X Wang Y Metcalf CA Liu S Chen I Romero J Zou D Sundaramoorthi R Li F Qi J Cai L Zhou T Commodore L Xu Q Keats J Wang F Wardwell S Ning Y Snodgrass JT Broudy MI Russian K Iuliucci J Rivera VM Sawyer TK Dalgarno DC Clackson T Shakespeare WC 《Bioorganic & medicinal chemistry letters》2011,21(12):3743-3748
Ponatinib (AP24534) was previously identified as a pan-BCR-ABL inhibitor that potently inhibits the T315I gatekeeper mutant, and has advanced into clinical development for the treatment of refractory or resistant CML. In this study, we explored a novel series of five and six membered monocycles as alternate hinge-binding templates to replace the 6,5-fused imidazopyridazine core of ponatinib. Like ponatinib, these monocycles are tethered to pendant toluanilides via an ethynyl linker. Several compounds in this series displayed excellent in vitro potency against both native BCR-ABL and the T315I mutant. Notably, a subset of inhibitors exhibited desirable PK and were orally active in a mouse model of T315I-driven CML. 相似文献
63.
Zheng C Cao G Xia M Feng H Glenn J Anand R Zhang K Huang T Wang A Kong L Li M Galya L Hughes RO Devraj R Morton PA Rogier DJ Covington M Baribaud F Shin N Scherle P Diamond S Yeleswaram S Vaddi K Newton R Hollis G Friedman S Metcalf B Xue CB 《Bioorganic & medicinal chemistry letters》2011,21(5):1442-1446
We report the discovery of a potent, selective, and orally bioavailable dual CCR2 and CCR5 antagonist (3S,4S)-N-[(1R,3S)-3-isopropyl-3-({4-[4-(trifluoromethyl)pyridin-2-yl]piperazin-1-yl}carbonyl)cyclopentyl]-3-methoxytetrahydro-2H-pyran-4-amine (19). After evaluation in 28-day toxicology studies, compound 19 (INCB10820/PF-4178903) was selected as a clinical candidate. 相似文献
64.
Ingo Aldag Ulrike Bockau Jan Rossdorf Sven Laarmann Willem Raaben Lutz Herrmann Thomas Weide Marcus WW Hartmann 《BMC biotechnology》2011,11(1):11
Background
Tetrahymena thermophila possesses many attributes that render it an attractive host for the expression of recombinant proteins. Surface proteins from the parasites Ichthyophthirius multifiliis and Plasmodium falciparum and avian influenza virus antigen H5N1 were displayed on the cell membrane of this ciliate. Furthermore, it has been demonstrated that T. thermophila is also able to produce a functional human DNase I. The present study investigates the heterologous expression of the functional human intestinal alkaline phosphatase (hiAP) using T. thermophila and thereby presents a powerful tool for the optimization of the ciliate-based expression system. 相似文献65.
Loubna Tazi Hiromi Imamichi Steven Hirschfeld Julia A Metcalf Susan Orsega Marcos Pérez-Losada David Posada H Clifford Lane Keith A Crandall 《BMC evolutionary biology》2011,11(1):62
Background
Replicate experiments are often difficult to find in evolutionary biology, as this field is inherently an historical science. However, viruses, bacteria and phages provide opportunities to study evolution in both natural and experimental contexts, due to their accelerated rates of evolution and short generation times. Here we investigate HIV-1 evolution by using a natural model represented by monozygotic twins infected synchronically at birth with an HIV-1 population from a shared blood transfusion source. We explore the evolutionary processes and population dynamics that shape viral diversity of HIV in these monozygotic twins. 相似文献66.
Thrombopoietin (TPO) is the cytokine that is chiefly responsible for megakaryocyte production but increasingly attention has turned to its role in maintaining hematopoietic stem cells (HSCs). HSCs are required to initiate the production of all mature hematopoietic cells, but this differentiation needs to be balanced against self-renewal and quiescence to maintain the stem cell pool throughout life. TPO has been shown to support HSC quiescence during adult hematopoiesis, with the loss of TPO signaling associated with bone marrow failure and thrombocytopenia. Recent studies have shown that constitutive activation mutations in Mpl contribute to myeloproliferative disease. In this review, we will discuss TPO signaling pathways, regulation of TPO levels and the role of TPO in normal hematopoiesis and during myeloproliferative disease.Key words: thrombopoietin, TPO, Mpl, hematopoietic stem cell, hematopoiesis, Jak2, MPLW515K, MPLW515L 相似文献
67.
68.
Enrichment was performed to isolate organisms that could utilize reduced phosphorus compounds as their sole phosphorus sources. One isolate that grew well with either hypophosphite or phosphite was identified by 16S rRNA gene analysis as a strain of Alcaligenes faecalis. The genes required for oxidation of hypophosphite and phosphite by this organism were identified by using transposon mutagenesis and include homologs of the ptxD and htxA genes of Pseudomonas stutzeri WM88, which encode an NAD-dependent phosphite dehydrogenase (PtxD) and 2-oxoglutarate-dependent hypophosphite dioxygenase (HtxA). This organism also has the htxB, htxC, and htxD genes that comprise an ABC-type transporter, presumably for hypophosphite and phosphite transport. The role of these genes in reduced phosphorus metabolism was confirmed by analyzing the growth of mutants in which these genes were deleted. Sequencing data showed that htxA, htxB, htxC, and htxD are virtually identical to their homologs in P. stutzeri at the DNA level, indicating that horizontal gene transfer occurred. However, A. faecalis ptxD is very different from its P. stutzeri homolog and represents a new ptxD lineage. Therefore, this gene has ancient evolutionary roots in bacteria. These data suggest that there is strong evolutionary selection for the ability of microorganisms to oxidize hypophosphite and phosphite. 相似文献
69.
Members of the third domain of life, the Archaea, possess structural, physiological, biochemical and genetic features distinct from Bacteria and Eukarya and, therefore, have drawn considerable scientific interest. Physiological, biochemical and molecular analyses have revealed many novel biological processes in these important prokaryotes. However, assessment of the function of genes in vivo through genetic analysis has lagged behind because suitable systems for the creation of mutants in most Archaea were established only in the past decade. Among the Archaea, sufficiently sophisticated genetic systems now exist for some thermophilic sulfur-metabolizing Archaea, halophilic Archaea and methanogenic Archaea. Recently, there have been developments in genetic analysis of thermophilic and methanogenic Archaea and in the use of genetics to study the physiology, metabolism and regulatory mechanisms that direct gene expression in response to changes of environmental conditions in these important microorganisms. 相似文献
70.
Oleg?V?Kovalenko Douglas?G?Metcalf William?F?DeGrado Martin?E?HemlerEmail author 《BMC structural biology》2005,5(1):11