oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 60 )

2018 ( 326 )

2017 ( 337 )

2016 ( 532 )

Custom range...

Search Results: 1 - 10 of 198020 matches for " N. Zoń "
All listed articles are free for downloading (OA Articles)
Page 1 /198020
Display every page Item
Modeling for transboundary water resources planning and allocation: the case of Southern Africa
D. Juízo,R. Lidén
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2010,
Abstract: International water resources agreements for transboundary rivers in southern Africa are generally founded in system analysis models for water planning and allocation. The Water Resources Yield Model (WRYM) developed in South Africa has so far been the only model applied in official joint water resources studies aimed to form water-sharing agreements. The continuous discussion around the model performance and growing distress over it being South African, where it was originally developed, while South Africa is one of the interested parties in the process, results in an increased controversy over the system analysis results that are often only meant to guide in selecting the options for water resources management in a given set of scenarios. The objective of this study was therefore to assess the model performance of two other models; WAFLEX and WEAP21 in the Umbeluzi River Basin system where the WRYM was previously applied as part of a Joint River Basin Study. A set of basin development scenarios was equally tested in the three models and the results compared. The results show that the three models all are possible tools for system analysis of river basins in southern Africa, although the structure and complexity of the models are different. The obtained level of satisfaction for specific water users could, however, vary depending on which model was used, which causes uncertainties. The reason for the diverse results is the structurally different ways of describing allocation and prioritization of water in the three models. However, the large degrees of freedom in all system models cause even larger uncertainty in the results since the model developer can, intentionally or unintentionally, direct the results to favor certain water user. The conclusion of this study is therefore that the choice of model does not per se affect the decision of best water allocation and infrastructure layout of a shared river basin. The chosen allocation and prioritization principles for the specific river basin and the model developer's experience and integrity are more important factors to find the optimal and equitable allocation.
Modeling for transboundary water resources planning and allocation
D. Juízo,R. Lidén
Hydrology and Earth System Sciences Discussions , 2008,
Abstract: International water resources agreements for transboundary rivers in southern Africa are based on system analysis models for water planning and allocation. The Water Resources Yield Model (WRYM) developed in South Africa has so far been the only model applied in official joint water resources studies aimed to form water-sharing agreements. The continuous discussion around the model performance and growing distress over it being South African, where it was originally developed, while South Africa is one of the interested parties in the process, results in an increased controversy over the system analysis results that are often only meant to guide in selecting the options for water resources management in a given set of scenarios. The objective of this study was therefore to assess the model performance of two other models; WAFLEX and WEAP21 in the Umbeluzi River Basin system where the WRYM was previously applied as part of a Joint River Basin Study. A set of basin development scenarios was equally tested in the three models and the results compared. The results show that the three models all are possible tools for system analysis of river basins in southern Africa, although the structure and complexity of the models are different. The obtained level of satisfaction for specific water users could, however, vary depending on which model was used, which causes uncertainties. The reason for the diverse results is the structurally different ways of describing allocation and prioritization of water in the three models. However, the large degrees of freedom in all system models cause even larger uncertainty in the results since the model user can, intentionally or unintentionally, direct the results to favor certain water users. The conclusion of this study is therefore that the choice of model does not per se affect the decision of best water allocation and infrastructure layout of a shared river basin. The chosen allocation and prioritization principles for the specific river basin and the model user's experience and integrity are more important factors to find the optimal and equitable allocation.
Distinct profiles of systemic biomarkers of oxidative stress in chronic human pathologies: Cardiovascular, psychiatric, neurodegenerative, rheumatic, infectious, neoplasmic and endocrinological diseases  [PDF]
Michel Brack, Olivier Brack, Yves Ménézo, Dominique Bonnefont Rousselot, Gerard Dreyfus, M. John Chapman Chapman, Anatol Kontush
Advances in Bioscience and Biotechnology (ABB) , 2013, DOI: 10.4236/abb.2013.43043
Abstract:

Oxidative stress is involved in chronic and acute pathologies: cardiovascular, neurodegenerative, neoplastic, inflammatory and infectious diseases. Clinical trials focused on prevention of cardiovascular and neoplastic diseases involving antioxidant supplementation have however provided predominantly negative obserations in large-scale studies. Screening of patient cohorts to assess baseline oxidative stress on the basis of a biomarker profile is decisive but lacking. For the first time, we evaluated the level of oxidative stress, testing more than 10 established biomarkers, in a comprehensive initial survey of 617 patients displaying chronic human pathologies. Multiple diseasespecific abnormalities were identified in plasma, whole blood and/or urine. This is the case for vitamins and oligo elements, vitamin C, vitamin E, β-carotene, selenium, zinc and copper; endogenous antioxidants such as reduced and oxidised glutathione, thiols, urate, and glutathione peroxidase activity, and a biomarker of oxidative DNA damage (8-hydroxy-2’-deoxy guanosine). The distinct biomarker profiles suggest the involvment of multiple forms of oxidative insults which are

A Decline in p38 MAPK Signaling Underlies Immunosenescence in Caenorhabditis elegans
Matthew J. Youngman,ZoN. Rogers,Dennis H. Kim
PLOS Genetics , 2011, DOI: 10.1371/journal.pgen.1002082
Abstract: The decline in immune function with aging, known as immunosenescence, has been implicated in evolutionarily diverse species, but the underlying molecular mechanisms are not understood. During aging in Caenorhabditis elegans, intestinal tissue deterioration and the increased intestinal proliferation of bacteria are observed, but how innate immunity changes during C. elegans aging has not been defined. Here we show that C. elegans exhibits increased susceptibility to bacterial infection with age, and we establish that aging is associated with a decline in the activity of the conserved PMK-1 p38 mitogen-activated protein kinase pathway, which regulates innate immunity in C. elegans. Our data define the phenomenon of innate immunosenescence in C. elegans in terms of the age-dependent dynamics of the PMK-1 innate immune signaling pathway, and they suggest that a cycle of intestinal tissue aging, immunosenescence, and bacterial proliferation leads to death in aging C. elegans.
The KdpD/KdpE Two-Component System: Integrating K+ Homeostasis and Virulence
ZoN. Freeman,Steve Dorus,Nicholas R. Waterfield
PLOS Pathogens , 2013, DOI: 10.1371/journal.ppat.1003201
Abstract: The two-component system (TCS) KdpD/KdpE, extensively studied for its regulatory role in potassium (K+) transport, has more recently been identified as an adaptive regulator involved in the virulence and intracellular survival of pathogenic bacteria, including Staphylococcus aureus, entero-haemorrhagic Escherichia coli, Salmonella typhimurium, Yersinia pestis, Francisella species, Photorhabdus asymbiotica, and mycobacteria. Key homeostasis requirements monitored by KdpD/KdpE and other TCSs such as PhoP/PhoQ are critical to survival in the stressful conditions encountered by pathogens during host interactions. It follows these TCSs may therefore acquire adaptive roles in response to selective pressures associated with adopting a pathogenic lifestyle. Given the central role of K+ in virulence, we propose that KdpD/KdpE, as a regulator of a high-affinity K+ pump, has evolved virulence-related regulatory functions. In support of this hypothesis, we review the role of KdpD/KdpE in bacterial infection and summarize evidence that (i) KdpD/KdpE production is correlated with enhanced virulence and survival, (ii) KdpE regulates a range of virulence loci through direct promoter binding, and (iii) KdpD/KdpE regulation responds to virulence-related conditions including phagocytosis, exposure to microbicides, quorum sensing signals, and host hormones. Furthermore, antimicrobial stress, osmotic stress, and oxidative stress are associated with KdpD/KdpE activity, and the system's accessory components (which allow TCS fine-tuning or crosstalk) provide links to stress response pathways. KdpD/KdpE therefore appears to be an important adaptive TCS employed during host infection, promoting bacterial virulence and survival through mechanisms both related to and distinct from its conserved role in K+ regulation.
Dynamic Scaling for First-order Phase Transtions
Banu Ebru ?zo?uz,Yi?it Gündü?,Meral Ayd?n
Physics , 2000,
Abstract: The critical behaviour in short time dynamics for the q=6 and 7 state Potts models in two-dimensions is investigated. It is shown that dynamic finite-size scaling exists for first-order phase transitions.
Suitability of charcoal from selected tropical plants for the production of blasting black powder
ZO Opafunso
Journal of Science and Technology (Ghana) , 2006,
Abstract: The performance characteristics of charcoal samples of five tropical plants were evaluated for the production of black powder for blasting, sporting and firework purposes. The charcoal produced from each of the tropical plants was used in combination with potassium nitrate and sulphur to produce black powders in the ratio of 2:3:0.5. With the foreign black powder as control, the produced black powders were subjected to ignition/deflagration field tests. The results show that the flame from the ignition of the black powder of trema orientalis were similar to that of foreign black powder. They were reddish in nature intermixed with yellowish colour and, therefore, would be suitable for blasting purposes. Also, that of manihot esculentas would do well for use as gunpowder for sporting purposes while that of cajanus cajan would be an ideal ingredient for the making of fireworks and Christmas "bisco" light. The performances of that of bambusa spp and tectona grandis were too poor for efficient blasting, sporting or firework purposes.
The Haunting of L.S. Lowry: Class, Mass Spectatorship and the Image at The Lowry, Salford, UK
Zo? Thompson
Societies , 2013, DOI: 10.3390/soc3040332
Abstract: In a series of momentary encounters with the surface details of The Lowry Centre, a cultural venue located in Salford, Greater Manchester, UK, this article considers the fate of the image evoked by the centre’s production and staging of cultural experience. Benjamin’s notion of ‘aura’ as inimical to transformations of art and cultural spectatorship is explored, alongside its fatal incarnation in Baudrillard’s concept of ‘simulation’. L.S. Lowry, I argue, occupies the space as a medium: both as a central figure of transmission of the centre’s narrative of inclusivity through cultural regeneration, and as one who communes with phantoms: remainders of the working-class life and culture that once occupied this locale. Through an exploration of various installations there in his name, Lowry is configured as a ‘destructive character’, who, by making possible an alternative route through its spaces, refuses to allow The Lowry Centre to insulate itself from its locale and the debt it owes to its past.
Maximal Radius of Quaternionic Hyperbolic Manifolds
Zoé Philippe
Mathematics , 2015,
Abstract: We derive an explicit lower bound on the radius of a ball embedded in a quaternionic hyperbolic manifold.
A note on canonical bases and one-based types in supersimple theories
Zoé Chatzidakis
Mathematics , 2011,
Abstract: This paper studies the CBP, a model-theoretic property first discovered by Pillay and Ziegler. We first show a general decomposition result of types of canonical bases, which one can think of as a sort of primary decomposition. This decomposition is then used to show that existentially closed difference fields of any characteristic have the CBP. We also derive consequences of the CBP, and use these results for applications to differential and difference varieties, and algebraic dynamics.
Page 1 /198020
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.