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Production of trans-Neptunian binaries through chaos-assisted capture  [PDF]
Ernestine A. Lee,Sergey A. Astakhov,David Farrelly
Physics , 2007, DOI: 10.1111/j.1365-2966.2007.11930.x
Abstract: The recent discovery of binary objects in the Kuiper-belt opens an invaluable window into past and present conditions in the trans-Neptunian part of the Solar System. For example, knowledge of how these objects formed can be used to impose constraints on planetary formation theories. We have recently proposed a binary-object formation model based on the notion of chaos-assisted capture. Here we present a more detailed analysis with calculations performed in the spatial (three-dimensional) three- and four-body Hill approximations. It is assumed that the potential binary partners are initially following heliocentric Keplerian orbits and that their relative motion becomes perturbed as these objects undergo close encounters. First, the mass, velocity, and orbital element distribu- tions which favour binary formation are identified in the circular and elliptical Hill limits. We then consider intruder scattering in the circular Hill four-body problem and find that the chaos-assisted capture mechanism is consistent with observed, apparently randomly distributed, binary mutual orbit inclinations. It also predicts asymmetric distributions of retrograde versus prograde orbits. The time-delay induced by chaos on particle transport through the Hill sphere is analogous to the formation of a resonance in a chemical reaction. Implications for binary formation rates are considered and the 'fine-tuning' problem recently identified by Noll et al. (2007) is also addressed.
PPARγ and LXR Signaling Inhibit Dendritic Cell-Mediated HIV-1 Capture and trans-Infection  [PDF]
Timothy M. Hanley,Wendy Blay Puryear,Suryaram Gummuluru,Gregory A. Viglianti
PLOS Pathogens , 2010, DOI: 10.1371/journal.ppat.1000981
Abstract: Dendritic cells (DCs) contribute to human immunodeficiency virus type 1 (HIV-1) transmission and dissemination by capturing and transporting infectious virus from the mucosa to draining lymph nodes, and transferring these virus particles to CD4+ T cells with high efficiency. Toll-like receptor (TLR)-induced maturation of DCs enhances their ability to mediate trans-infection of T cells and their ability to migrate from the site of infection. Because TLR-induced maturation can be inhibited by nuclear receptor (NR) signaling, we hypothesized that ligand-activated NRs could repress DC-mediated HIV-1 transmission and dissemination. Here, we show that ligands for peroxisome proliferator-activated receptor gamma (PPARγ) and liver X receptor (LXR) prevented proinflammatory cytokine production by DCs and inhibited DC migration in response to the chemokine CCL21 by preventing the TLR-induced upregulation of CCR7. Importantly, PPARγ and LXR signaling inhibited both immature and mature DC-mediated trans-infection by preventing the capture of HIV-1 by DCs independent of the viral envelope glycoprotein. PPARγ and LXR signaling induced cholesterol efflux from DCs and led to a decrease in DC-associated cholesterol, which has previously been shown to be required for DC capture of HIV-1. Finally, both cholesterol repletion and the targeted knockdown of the cholesterol transport protein ATP-binding cassette A1 (ABCA1) restored the ability of NR ligand treated cells to capture HIV-1 and transfer it to T cells. Our results suggest that PPARγ and LXR signaling up-regulate ABCA1-mediated cholesterol efflux from DCs and that this accounts for the decreased ability of DCs to capture HIV-1. The ability of NR ligands to repress DC mediated trans-infection, inflammation, and DC migration underscores their potential therapeutic value in inhibiting HIV-1 mucosal transmission.
HIV-1 Capture and Transmission by Dendritic Cells: The Role of Viral Glycolipids and the Cellular Receptor Siglec-1  [PDF]
Nuria Izquierdo-Useros ,Maier Lorizate,Paul J. McLaren,Amalio Telenti,Hans-Georg Kr?usslich ? ,Javier Martinez-Picado ?
PLOS Pathogens , 2014, DOI: doi/10.1371/journal.ppat.1004146
Abstract: Dendritic cells (DCs) are essential in order to combat invading viruses and trigger antiviral responses. Paradoxically, in the case of HIV-1, DCs might contribute to viral pathogenesis through trans-infection, a mechanism that promotes viral capture and transmission to target cells, especially after DC maturation. In this review, we highlight recent evidence identifying sialyllactose-containing gangliosides in the viral membrane and the cellular lectin Siglec-1 as critical determinants for HIV-1 capture and storage by mature DCs and for DC-mediated trans-infection of T cells. In contrast, DC-SIGN, long considered to be the main receptor for DC capture of HIV-1, plays a minor role in mature DC-mediated HIV-1 capture and trans-infection.
The future of Carbon Capture and Storage (CCS) in Nigeria
M Anastassia, O Fredrick, W Malcolm
Science World Journal , 2009,
Abstract: Carbon Capture and Storage (CCS) is one of the techniques for greenhouse gas (GHG) emissions reduction. This article reviews the current status of CCS technology, highlights costs and discusses legal and regulatory issues of CCS. The main purpose of the article is to review CCS and CO2-EOR experience from ongoing projects in different parts of the world and give recommendations on how this knowledge can be applied in Nigeria. A potential demonstration CO2-EOR project in Nigeria under the Clean Development Mechanism (CDM) is discussed.
Options for sampling and stratification for national forest inventories to implement REDD+ under the UNFCCC
Danae Maniatis, Danilo Mollicone
Carbon Balance and Management , 2010, DOI: 10.1186/1750-0680-5-9
Abstract: First, we present the key indispensable elements of the IPCC Guidance and Guidelines that have been developed to fulfil the UNFCCC reporting requirements. This is done in order to set the framework to develop the MRV requirement in which a NFI for REDD+ implementation could be developed. Second, within this framework, we develop and propose a novel scheme for the stratification of forest land for REDD+. Finally, we present some non-exhaustive optional elements within this framework that a country could consider to successfully operationalise and implement its REDD+ NFI.Evidently, both the methodological guidance and political decisions on REDD+ under the UNFCCC will continue to evolve. Even so, and considering that there exists decades of experience in setting up traditional NFIs, developing a NFI that a country may use to directly support REDD+ activities under the UNFCCC represents the development of a new challenge in this field. It is therefore important that both the scientific community and national implementing agencies acquaint themselves with both the context and content of this challenge so that REDD+ mitigation actions may be implemented successfully and with environmental integrity. This paper provides important contributions to the subject through our proposal of the stratification of forest land for REDD+.Since 2005 and in the context of the United Nations Framework Convention on Climate Change (UNFCCC) negotiations on a climate deal, activities related to forest land (FL) in developing countries have become one of the key possible mechanisms for climate change mitigation. In December 2009, the 15th meeting of the Conference of the Parties (COP) resulted in a Decision on 'Methodological guidance for activities relating to reducing emissions from deforestation and forest degradation and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries', or REDD+ [1]. In December 2010, the 16th me
Revista Facultad de Ciencias Económicas: Investigación y Reflexión , 2010,
Abstract: climate change is seen as one of the environmental problems with major impacts on human and natural systems. the concern of society about this problem is increasing as a result of increasing scientific evidence and catastrophic events, which is why we have sought an answer anthropogenic (sabogal, 2007). projects development mechanism (cdm) are part of the settlement proposal, however, contrary to the regulations of the kyoto protocol, its impact is not as clear in terms of sustainability. this article evaluates the presence and fulfillment of the objectives of sustainability in cdm projects submitted to the convention united nations framework on climate change and the kyoto protocol (unfccc) for the period between 2004 and 2008, identifying global trends and make recommendations for improvement in the implementation of these mechanisms.
Carbon Capture and Storage: A Challenging Approach for Mitigation of Global Warming  [PDF]
Hai Yu
International Journal of Clean Coal and Energy (IJCCE) , 2013, DOI: 10.4236/ijcce.2013.23003
Abstract: Carbon Capture and Storage: A Challenging Approach for Mitigation of Global Warming
The SECARB Anthropogenic Test: A US Integrated CO2 Capture, Transportation and Storage Test  [PDF]
George Koperna, David Riestenberg, Vello Kuuskraa, Richard Rhudy, Robert Trautz, Gerald R. Hill, Richard Esposito
International Journal of Clean Coal and Energy (IJCCE) , 2012, DOI: 10.4236/ijcce.2012.12002
Abstract: The United States Department of Energy (DOE) seeks to validate the feasibility of injecting, storing and monitoring CO2 in the subsurface (geologic storage) as an approach to mitigate atmospheric emissions of CO2. In an effort to pro- mote the development of a framework and the infrastructure necessary for the validation and deployment of carbon sequestration technologies, DOE established seven Regional Carbon Sequestration Partnerships (RCSPs). The South- east Regional Carbon Sequestration Partnership (SECARB), whose lead organization is the Southern States Energy Board (SSEB), represents 13 States within the southeastern United States of America (USA). The SECARB Anthropo- genic Test R&D project is a demonstration of the deployment of CO2 capture, transport, geologic storage and monitor- ing technology. This project is an integral component of a plan by Southern Company, and its subsidiary, Alabama Power, to demonstrate integrated CO2 capture, transport and storage technology. The capture component of the test takes place at the James M. Barry Electric Generating Plant (Plant Barry) in Bucks, Alabama. The capture facility, equivalent to 25 MW, will utilize post-combustion amine capture technology licensed from Mitsubishi Heavy Industries America. CO2 captured at the plant will be transported by pipeline for underground storage in a deep, saline geologic formation within the Citronelle Dome located in Citronelle, Alabama. At the end of the first quarter of 2012, up to 550 tonnes of CO2 per day will be captured and transported twelve miles by pipeline to the storage site for injection and subsurface storage. The injection target is the lower Cretaceous Paluxy Formation which occurs at 9400 feet. Trans- portation and injection operations will continue for one to two years. Subsurface monitoring will be deployed through 2017 to track plume movement and monitor for leakage. This project will be one of the first and the largest fully-inte- grated commercial prototype coal-fired carbon capture and storage projects in the USA. This paper will discuss the re- sults to date, including permitting efforts, baseline geologic analysis and detailed reservoir modeling of the storage site, framing the discussion in terms of the overall goals of the project.
The practical stability of anticancer drugs: SFPO and ESOP recommendations
Alain Astier,Frédéric Pinguet,Jean Vigneron,SFPO Stability Group members
European Journal of Oncology Pharmacy , 2010,
Abstract: The publication of European recommendations for the storage conditions of reconstituted and diluted solutions of oncology drugs as they are used in practice is a major achievement. These recommendations will be referred to frequently by hospital and oncology pharmacists.
An approach to estimate carbon stocks change in forest carbon pools under the UNFCCC: the Italian case
Federici S,Vitullo M,Tulipano S,De Lauretis R
iForest : Biogeosciences and Forestry , 2008, DOI: -
Abstract: Under the UNFCCC, Annex I Parties must report annually a National GHG Inventories of anthropogenic emissions by sources and removals by sinks. LULUCF is one of the six sectors of the inventory: in this sector any emissions and removals of GHGs by land management should be reported, included the large GHGs fluxes generated by forest management and land-use changes into and from forest. In this context every Party has to produce a proper model in order to be able to fulfil GHGs Inventory request for forest sector. Taking Italy as a study case, the paper aims at presenting a new methodology for updating stock changes for years between national forest inventories, in order to reproduce annual stock changes in the five UNFCCC forest carbon pools, following the UNFCCC requirements in the context of carbon reporting.
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