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A Network of SLC and ABC Transporter and DME Genes Involved in Remote Sensing and Signaling in the Gut-Liver-Kidney Axis.
Genes central to drug absorption, distribution, metabolism and elimination (ADME) also regulate numerous endogenous molecules. The Remote Sensing and Signaling Hypothesis argues that an ADME gene-centered network-including SLC and ABC "drug" transporters, "drug" metabolizing enzymes (DMEs), and regulatory genes-is essential for inter-organ communication via metabolites, signaling molecules, antioxidants, gut microbiome products, uremic solutes, and uremic toxins. By cross-tissue co-expression network analysis, the gut, liver, and kidney (GLK) formed highly connected tissue-specific clusters of SLC transporters, ABC transporters, and DMEs. SLC22, SLC25 and SLC35 families were network hubs, having more inter-organ and intra-organ connections than other families. Analysis of the GLK network revealed key physiological pathways (e.g., involving bile acids and uric acid). A search for additional genes interacting with the network identified HNF4α, HNF1α, and PXR. Knockout gene expression data confirmed ~60-70% of predictions of ADME gene regulation by these transcription factors. Using the GLK network and known ADME genes, we built a tentative gut-liver-kidney "remote sensing and signaling network" consisting of SLC and ABC transporters, as well as DMEs and regulatory proteins. Together with protein-protein interactions to prioritize likely functional connections, this network suggests how multi-specificity combines with oligo-specificity and mono-specificity to regulate homeostasis of numerous endogenous small molecules
Optimal Slewing of a Constrained Telescope Using Seventh Order Polynomial Input Torques
Two-axis gimbals are frequently used to point cameras and telescopes at various points of interest for surveillance, science, and art. The rotation of a two-axis gimbal system is governed by nonlinear angular momentum equations of motion. This paper presents a method for slewing a telescope in space with a gimbaled sensor attached to a nominally non-rotating spacecraft using two seventh order polynomial input functions to characterize torques. To accomplish this task, picking the optimal coefficients of the seventh order polynomial was necessary. It was also desired to use constraint equations to limit the excursion, angular velocity, angular acceleration, and jerk of the gimbal. A Matlab code was developed for this purpose. Matlab’s fmincon was used to do the optimization, and a comparison to a previously validated one-degree-of-freedom (DOF) model was presented for validation of the nonlinear, two-degree-of-freedom model. Results for a fully constrained 2 DOF slew maneuver were also shown. This thesis demonstrates that seventh order polynomial torques can be used to accurately slew a telescope in space using nonlinear equations of motion
The economic value of Albertine Rift Forests; applications in policy and programming
The objective of this thesis is to quantitatively understand the economic performance of protected area management strategies for forest and biodiversity conservation. Examples such as integrated conservation and development and eco tourism are assessed in terms of their ability to deliver on welfare benefits to local communities, and an assessment of the opportunity costs of forest conservation as a land use strategy. In addition the contribution of forest conservation in protected areas can make to poverty alleviation and economic development is also examined. The geographical focus of this study is the Albertine Rift region of East and Central Africa, stretching north from the southern end of Lake Tanganyika through the spine of Africa to the northern end of Lake Albert. The Albertine Rift is one of Africa’s most important landscapes for the conservation of forests and biodiversity.
The overarching objective is addressed using a series of case studies empirically valuing the opportunity costs of conserving forests in a selection of sites in the central part of the Albertine Rift. The success of conservation is most often measured against progress in reducing habitat or species loss and not often in terms of the contribution of the protected area to poverty alleviation and local economic development. Achieving improvements of conservation strategies in the social dimension requires objective evidence on their effects. Economic valuation of protected area resources provides a quantitative means of assessing the promise and performance of conservation policies in achieving welfare benefits to local communities.
This thesis provides three case studies each addressing current valuation and social issues in conservation and sets them in a context of managing protected areas in the broad dynamic setting of poverty alleviation and economic growth from a developing economy perspective. In addition two of the empirical studies are as concerned with methodological enquiry and the performance of novel environmental economic valuation techniques, such as the contingent valuation and choice modelling approaches, as the application of results to conservation questions.
The empirical studies show that the benefits to local households and communities from their local forests may be greater than at first perceived. Across all protected area categories, biomes and income groups, households derived significant amounts of their overall income from their local protected area with large proportions of the value of goods harvested from forests being consumed in the home. Amongst income groups high income households often appropriated a greater share of the value of forest goods. There was no significant difference found between the household consumption and the sale of protected area products between income groups. The findings indicate that imposing reductions in forest use may increase poverty amongst local people whilst increasing household income will not necessarily reduce forest exploitation. This indicates that community conservation and integrated conservation and development programmes must target the poor forest adjacent households more actively to ensure poverty alleviation, whilst providing improved protection and law enforcement for effective conservation.
It is also shown that biodiversity conservation can have an economic return through mountain gorilla eco-tourism. Findings show a disparity between what constitutes eco-tourism and the real values of tourists towards biodiversity conservation and local social benefits from protected areas. Despite showing a high marginal utility for biodiversity conservation, consumers are unwilling to pay for local community benefits from tourism as part of the permit price to view gorillas. Clearly the link between successful conservation and the welfare status of local communities is not sufficiently established in the minds of consumers to influence their spending decisions.
The challenges of effectively mobilising communities to protect biodiversity are discussed in the context of the variable impacts of integrated conservation and development programs over the last three decades. Direct payment payments for conservation services schemes are discussed as an innovative tool to add to the gamut of community approaches currently on offer. Payments for conservation schemes are viewed with cautious optimism in terms of their possibility for success. Despite their allure of being more economically and socially efficient at achieving welfare and conservation objectives, given the complex nature of any society, no less research in to social and economic dynamics of protected area use by local communities would be needed to ensure success of such schemes. However, the overwhelming majority of benefits form protected areas are tied up in ecosystem services values. Mechanisms to generate funding and distribute payments for these benefits in terms of offsetting the local opportunity costs are essential to change local behavior and reduce forest degradation and destruction
Wetlands governance in the Mekong Region: country reports on the legal-institutional framework and economic valuation of aquatic resources
Wetlands are central to the livelihoods of rural communities through out the Mekong Region, providing vital functions and services that support the rural economy, ensure food security for the most vulnerable membrs of society, and underpin the prospects for national development. Proper appreciation of the importance of wetlands has been hampered by inadequate information and awareness of their uses, particularly among development planners, as well as legal and institutional frameworks that are often fragmented and poorly enforced. Wetlands are consistently undervalued and overlooked as a result, and ultimately, it is the rural poor who lose out.Wetlands-Economic aspects, Wetlands-Law and legislation, Socioeconomic aspects, Aquatic resources, WorldFish Center Contrib. No. 1754, Mekong Delta, Thailand, Cambodia, Vietnam, Lao PDR,
Characteristics of Magnetohydrodynamic Oscillations Observed with Michelson Doppler Imager
We report on the spatial distribution of magnetogram oscillatory power and
phase angles between velocity and magnetogram signals as observed with the
Michelson Doppler Imager. The dataset is 151.25 arcsec times 151.25 arcsec
containing sunspot from Dec 2, 1997 with a temporal sampling interval of 60
seconds and spatial sampling of 0.605 arcsec. Simultaneously observed continuum
intensity and surface velocity accompany the magnetic information. We focus on
three frequency regimes: 0.5-1.0, 3.0-3.5 and 5.5-6.0 mHz corresponding roughly
to timescales of magnetic evolution, p-modes and the 3 minute resonant sunspot
oscillation. Significant low frequency magnetogram power is found in lower flux
pixels, 100-300 Gauss, in a striking ring with filamentary structure
surrounding sunspot. Five minute magnetogram power peaks in extended regions of
flux 600-800 Gauss. The 3 minute oscillation is observed in sunspot umbra in
pixels whose flux measures 1300-1500 Gauss. Phase angles of approximately -90
degrees between velocity and magnetic flux in the 3.0-3.5 and 5.5-6.0 mHz
regimes are found in regions of significant cross amplitude.Comment: 4 Pages, 4 Figures -- For better Figure files see:
http://www.astro.ucla.edu/~norton/pub_list.htm
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