847 resultados para Outlines of Pyrrhonism
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Self-help groups (SHGs) are ways for farmers and fishers, especially those who are poor, to come together and work together. They can be a useful entry point for outsiders, promote a supportive local environment, strengthen voices in decision-making and in negotiations with more powerful forces, increase the effectiveness of local actions, and provide easier access to micro-credit and other resources and services. This case study describes a rural aquaculture development context, in India, the development of SHGs and the concept of a ‘one-stop aqua shop’, set up and run by a federation of self-help groups in Kaipara village, West Bengal (a pilot state along with Jharkhand and Orissa). It outlines testing new ways to share information, as part of a series of revised procedures and institutional arrangements for service delivery recommended by farmers and fishers and prioritized by government, with support from the Department of International Development, London (DFID) Natural Resources Support Programme (NRSP) and the Network of Aquaculture Centres in Asia-Pacific (NACA) to the Support to Regional Aquatic Resources Management (STREAM) Initiative (10 p.)
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Increased boating activities and new waterfront developments have contributed an estimated 3,000 dismantled, abandoned, junked, wrecked, derelict vessels to Florida coastal waters. This report outlines a method of siting and prioritizing derelict vessel removal using the Florida Keys as a test area. The data base was information on 240 vessels, obtained from Florida Marine Patrol files. Vessel location was plotted on 1:250,000 regional and 1:5,000 and 1:12,000 site maps. Type of vessel, length, hull material, engine, fuel tanks, overall condition, afloat and submerged characteristics, and accessibility, were used to derive parametric site indices of removal priority and removal difficulty. Results indicate 59 top priority cases which should be the focus of immediate clean up efforts in the Florida Keys. Half of these cases are rated low to moderate in removal difficulty; the remainder are difficult to remove. Removal difficulty is a surrogate for removal cost: low difficulty -low cost, high difficulty - high cost. The rating scheme offers coastal planners options of focusing removal operations either on (1) specific areas with clusters of high priority derelict vessels or on (2) selected targeted derelicts at various, specific locations. (PDF has 59 pages.)
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In accordance with the Marine Mammal Protection Act (MMPA, 16 U.S.c. et seq.), the National Marine Fisheries Service (NMFS) is required to publish an annual List of Fisheries (LOF) which categorizes U.S. commercial fisheries based on their level of interaction with marine mammals. The objective of this document is to provide a characterization of the six 2001 MMPA Category II commercial fisheries (i.e., those with occasional interactions with marine mammals) in North Carolina (NC). This report outlines the history, fishing method and gear configurations (using the U.S. system of measurement), primary target species, temporal and spatial characteristics including trip and landing statistics, and monthly variations in species composition for each fishery for a five-year period (1995 - 1999). (PDF contains 63 pages)
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Executive Summary: The Estuary Restoration Act of 2000 (ERA), Title I of the Estuaries and Clean Waters Act of 2000, was created to promote the restoration of habitats along the coast of the United States (including the US protectorates and the Great Lakes). The NOAA National Centers for Coastal Ocean Science was charged with the development of a guidance manual for monitoring plans under this Act. This guidance manual, titled Science-Based Restoration Monitoring of Coastal Habitats, is written in two volumes. It provides technical assistance, outlines necessary steps, and provides useful tools for the development and implementation of sound scientific monitoring of coastal restoration efforts. In addition, this manual offers a means to detect early warnings that the restoration is on track or not, to gauge how well a restoration site is functioning, to coordinate projects and efforts for consistent and successful restoration, and to evaluate the ecological health of specific coastal habitats both before and after project completion (Galatowitsch et al. 1998). The following habitats have been selected for discussion in this manual: water column, rock bottom, coral reefs, oyster reefs, soft bottom, kelp and other macroalgae, rocky shoreline, soft shoreline, submerged aquatic vegetation, marshes, mangrove swamps, deepwater swamps, and riverine forests. The classification of habitats used in this document is generally based on that of Cowardin et al. (1979) in their Classification of Wetlands and Deepwater Habitats of the United States, as called for in the ERA Estuary Habitat Restoration Strategy. This manual is not intended to be a restoration monitoring “cookbook” that provides templates of monitoring plans for specific habitats. The interdependence of a large number of site-specific factors causes habitat types to vary in physical and biological structure within and between regions and geographic locations (Kusler and Kentula 1990). Monitoring approaches used should be tailored to these differences. However, even with the diversity of habitats that may need to be restored and the extreme geographic range across which these habitats occur, there are consistent principles and approaches that form a common basis for effective monitoring. Volume One, titled A Framework for Monitoring Plans under the Estuaries and Clean Waters Act of 2000, begins with definitions and background information. Topics such as restoration, restoration monitoring, estuaries, and the role of socioeconomics in restoration are discussed. In addition, the habitats selected for discussion in this manual are briefly described. (PDF contains 116 pages)
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This report outlines the potential impacts of coastal protection structures on the resources of the Monterey Bay National Marine Sanctuary. At least 15 miles of the Sanctuary’s 300-mile shoreline are currently armored with seawalls and riprap revetments. Most of these coastal protection structures are placed above the mean high tide line, the official boundary of the Sanctuary, yet some influences of armoring impinge on the marine realm and on recreational use. In addition, continued sea level rise and accompanying coastal retreat will force many of these structures below the high tide line over time. The Monterey Bay National Marine Sanctuary staff has recognized the significance of coastal armoring, identifying it as a critical issue in the Coastal Armoring Action Plan of the draft Joint Management Plan. This summary is intended to provide general background information for Sanctuary policies on coastal armoring. The impacts discussed include: aesthetic depreciation, beach loss due to placement, access restriction, loss of sand supply from eroding cliffs, passive erosion, and active erosion. In addition, the potential biological impacts are explored. Finally, an appraisal of how differing armor types compare in relation to impacts, expense and engineering is presented. While the literature cited in this report focus predominantly on the California coast, the framework for this discussion could have implications for other actively eroding coastlines. (PDF contains 26 pages.)
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A synthesis report based on the final report of the FE digital student study into FE students' expectations and experiences of the digital environment. The report outlines the key challenges, learning provider solutions, sector solutions and commentary on main findings. Appendix 2 includes a list of project outputs.
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The governing council of Naca has resolved to effect a shift in emphasis from aquaculture development to aquaculture for development. This will require engaging partners from a broad spectrum of government and development agencies, the nature of the information that will need to be gathered and the strategies used for disseminating information and initiating action. The vehicle for operationalising this shift is STREAM - Support to Regional Aquatic Resources Management. This report outlines the nature of the STREAM network, its relationship to NACA's vision, mission, objectives and operating principles, and how STREAM differs from previous NACA's networks. Because STREAM is different, a theoretical basis for network communication is presented along with an outline of the preliminary steps in getting the network up and running. (Pdf contains 33 pages).
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Diagnosis and adaptive management can help improve the ability of small-scale fisheries (SSF) in the developing world to better cope with and adapt to both external drivers and internal sources of uncertainty. This paper presents a framework for diagnosis and adaptive management and discusses ways of implementing the first two phases of learning: diagnosis and mobilising an appropriate management constituency. The discussion addresses key issues and suggests suitable approaches and tools as well as numerous sources of further information. Diagnosis of a SSF defines the system to be managed, outlines the scope of the management problem in terms of threats and opportunities, and aims to construct realistic and desired future projections for the fishery. These steps can clarify objectives and lead to development of indicators necessary for adaptive management. Before management, however, it is important to mobilize a management constituency to enact change. Ways of identifying stakeholders and understanding both enabling and obstructive interactions and management structures are outlined. These preliminary learning phases for adaptive SSF management are expected to work best if legitimised by collaborative discussion among fishery stakeholders drawing on multiple knowledge systems and participatory approaches to assessment. (PDF contains 33 pages)
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Under the regional programme Fisheries and HIV/AIDS in Africa: Investing in Sustainable Solutions, the WorldFish Center conducted this study on access to health services and vulnerabilities of female fish traders in the Kafue Flats floodplains in Zambia. This report outlines and analyses the particular vulnerabilities of female fish traders in the Kafue Flats fishery and formulates recommendations to facilitate stakeholder uptake of strategic responses to tackle the drivers of the epidemic in fishing communities and improve the livelihoods of fisher folk and fish traders in the Kafue Flats and other fisheries in Zambia. (pdf contains 55 pages)
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Molecules that inhibit DNA dependent processes are the most commonly used agents for the treatment of cancer. The genotoxicity associated with their mechanisms of action, unfortunately, make them extremely toxic to the patient and cancer cells alike. The work presented in this thesis outlines the development of Py-Im polyamides as non-genotoxic DNA-targeted antitumor molecules that interfere with RNA polymerase II elongation. We initially characterized the pharmacokinetic profiles of two hairpin polyamides to establish their bioavailability in the serum and tissues after a single administration. We next determined the molecular mechanism that contributes to toxicity of a hairpin polyamide in human prostate cancer cells in cell culture and we demonstrated antitumor effects of the compound against LNCaP xenografts in mice. Finally, we conducted animal toxicity experiments on 4 polyamides that vary on the gamma-turn with respect to the substitution of amino and acetamide groups at the alpha and beta positions. From this study we identified a second generation compound that retains antitumor activity with significantly reduce animal toxicity. This work sets the foundation for the development of Py-Im polyamides as DNA targeted therapeutics for the treatment of advanced prostate cancer.
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This thesis describes the preparation, characterization, and application of welldefined single-component group ten salicylaldimine complexes for the polymerization of ethylene to high molecular weight materials as well as the copolymerization of ethylene and functionalized olefins. After an initial introduction to the field, Chapter 2 describes the preparation of PPh3 complexes that contain a series of modified salicylaldimine and naphthaldimine ligands. Such complexes were activated for polymerization by the addition of cocatalysts such as Ni(COD)2 or B(C6F5)3. As the steric demand of the ligand set increased-the molecular weight, polymerization activity, and lifetime of the catalyst was observed to increase. In fact, complexes containing "bulky" ligands, such as the [Anthr,HSal] ligand (2.5), were found to be highly-active single component complexes for the polymerization of ethylene. Model hydrido compound were prepared-allowing for a better understanding of both the mechanism of polymerization and one mode of decomposition.
Chapter 3 describes the effect which additives play on neutral NiII polymerization catalysts such as 2.5. The addition of excess ethers, esters, ketones, anhydrides, alcohols, and water do not deactivate the catalysts for polymerization. However, the addition of excess acid, thiols, and phosphines was observed to shut-down catalysis. Since excess phosphine was found to inhibit catalysis, "phosphine-free" complexes, such as the acetonittile complex (3.26), were prepared. The acetonitrile complex was found to be the most active neutral polymerization catalyst prepared to date.
Chapter 4 outlines the use of catalyst 2.5 and 3.26 for the preparation of linear functionalized copolymers containing alcohols, esters, anhydrides, and ethers. Copolymers can be prepared with γ-functionalized-α-olefins, functionalized norbornenes, and functionalized tricyclononenes, with up to 30 mol% comonomer incorporation.
Chapter 5 outlines the preparation of a series of PtII alkyl/olefin salicylaldimine complexes which serve as models for the active species in the NiII-catalyzed polymerization process. Understanding the nature of the M-olefin interaction as a the electronic and steric properties of the salicylaldimine ligand is varied has allowed for a number of predictions about the design of future polymerization systems.
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This dissertation primarily describes chemical-scale studies of G protein-coupled receptors and Cys-loop ligand-gated ion channels to better understand ligand binding interactions and the mechanism of channel activation using recently published crystal structures as a guide. These studies employ the use of unnatural amino acid mutagenesis and electrophysiology to measure subtle changes in receptor function.
In chapter 2, the role of a conserved aromatic microdomain predicted in the D3 dopamine receptor is probed in the closely related D2 and D4 dopamine receptors. This domain was found to act as a structural unit near the ligand binding site that is important for receptor function. The domain consists of several functionally important noncovalent interactions including hydrogen bond, aromatic-aromatic, and sulfur-π interactions that show strong couplings by mutant cycle analysis. We also assign an alternate interpretation for the linear fluorination plot observed at W6.48, a residue previously thought to participate in a cation-π interaction with dopamine.
Chapter 3 outlines attempts to incorporate chemically synthesized and in vitro acylated unnatural amino acids into mammalian cells. While our attempts were not successful, method optimizations and data for nonsense suppression with an in vivo acylated tRNA are included. This chapter is aimed to aid future researchers attempting unnatural amino acid mutagenesis in mammalian cells.
Chapter 4 identifies a cation-π interaction between glutamate and a tyrosine residue on loop C in the GluClβ receptor. Using the recently published crystal structure of the homologous GluClα receptor, other ligand-binding and protein-protein interactions are probed to determine the similarity between this invertebrate receptor and other more distantly related vertebrate Cys-loop receptors. We find that many of the interactions previously observed are conserved in the GluCl receptors, however care must be taken when extrapolating structural data.
Chapter 5 examines inherent properties of the GluClα receptor that are responsible for the observed glutamate insensitivity of the receptor. Chimera synthesis and mutagenesis reveal the C-terminal portion of the M4 helix and the C-terminus as contributing to formation of the decoupled state, where ligand binding is incapable of triggering channel gating. Receptor mutagenesis was unable to identify single residue mismatches or impaired protein-protein interactions within this domain. We conclude that M4 helix structure and/or membrane dynamics are likely the cause of ligand insensitivity in this receptor and that the M4 helix has an role important in the activation process.
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In order to develop better catalysts for the cleavage of aryl-X bonds fundamental studies of the mechanism and individual steps of the mechanism have been investigated in detail. As the described studies are difficult at best in catalytic systems, model systems are frequently used. To study aryl-oxygen bond activation, a terphenyl diphosphine scaffold containing an ether moiety in the central arene was designed. The first three chapters of this dissertation focus on the studies of the nickel complexes supported by this diphosphine backbone and the research efforts in regards to aryl-oxygen bond activation.
Chapter 2 outlines the synthesis of a variety of diphosphine terphenyl ether ligand scaffolds. The metallation of these scaffolds with nickel is described. The reactivity of these nickel(0) systems is also outlined. The systems were found to typically undergo a reductive cleavage of the aryl oxygen bond. The mechanism was found to be a subsequent oxidative addition, β-H elimination, reductive elimination and (or) decarbonylation.
Chapter 3 presents kinetic studies of the aryl oxygen bond in the systems outlined in Chapter 2. Using a series of nickel(0) diphosphine terphenyl ether complexes the kinetics of aryl oxygen bond activation was studied. The activation parameters of oxidative addition for the model systems were determined. Little variation was observed in the rate and activation parameters of oxidative addition with varying electronics in the model system. The cause of the lack of variation is due to the ground state and oxidative addition transition state being affected similarly. Attempts were made to extend this study to catalytic systems.
Chapter 4 investigates aryl oxygen bond activation in the presence of additives. It was found that the addition of certain metal alkyls to the nickel(0) model system lead to an increase in the rate of aryl oxygen bond activation. The addition of excess Grignard reagent led to an order of magnitude increase in the rate of aryl oxygen bond activation. Similarly the addition of AlMe3 led to a three order of magnitude rate increase. Addition of AlMe3 at -80 °C led to the formation of an intermediate which was identified by NOESY correlations as a system in which the AlMe3 is coordinated to the ether moiety of the backbone. The rates and activation parameters of aryl oxygen bond activation in the presence of AlMe3 were investigated.
The last two chapters involve the study of metalla-macrocycles as ligands. Chapter 5 details the synthesis of a variety of glyoxime backbones and diphenol precursors and their metallation with aluminum. The coordination chemistry of iron on the aluminum scaffolds was investigated. Varying the electronics of the aluminum macrocycle was found to affect the observed electrochemistry of the iron center.
Chapter 6 extends the studies of chapter 5 to cobalt complexes. The synthesis of cobalt dialuminum glyoxime metal complexes is described. The electrochemistry of the cobalt complexes was investigated. The electrochemistry was compared to the observed electrochemistry of a zinc analog to identify the redox activity of the ligand. In the presence of acid the cobalt complexes were found to electrochemically reduce protons to dihydrogen. The electronics of the ancillary aluminum ligands were found to affect the potential of proton reduction in the cobalt complexes. These potentials were compared to other diglyoximate complexes.
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This article explores aspects of sustainability and the importance of sustainable development, including the place of the crucially important resource of fresh water and of freshwater ecosystems. It examines the treatment of natural resources by the economic system that underpins global business, outlines some progress towards more sustainable approaches to business, and recommends steps to re-establish science as the driver of wise policies that contribute to sustainable development.
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This article outlines the development of freshwater science between 1900 and 2000 and in particular traces British contributions, both to a deepened knowledge of specifics and to their interrelation as environmental and ecological science. The author provides a selected bibliography of important publications relevant to the topic of the article.