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Greedy Friensdhip Decompositions of Graphs  [PDF]
Teresa Sousa
Open Journal of Discrete Mathematics (OJDM) , 2011, DOI: 10.4236/ojdm.2011.11004
Abstract: A graph that consists of t cliques sharing a vertex v is said to be a t-friendship graph with center v. A friendship graph is a graph that is t-friendship for some . We solve the problem of finding the best upper bound for the size of a greedy 2-friendship decomposition and a greedy friendship decomposition of graphs of order n.
The H-Decomposition Problem for Graphs  [PDF]
Teresa Sousa
Applied Mathematics (AM) , 2012, DOI: 10.4236/am.2012.311237
Abstract: The concept of H-decompositions of graphs was first introduced by Erd?s, Goodman and Pósa in 1966, who were motivated by the problem of representing graphs by set intersections. Given graphs G and H, an H-decomposition of G is a partition of the edge set of G such that each part is either a single edge or forms a graph isomorphic to H. Let Ф(n,H) be the smallest number Ф, such that, any graph of order n admits an H-decomposition with at most Ф parts. The exact computation of Ф(n,H) for an arbitrary H is still an open problem. Recently, a few papers have been published about this problem. In this survey we will bring together all the results about H-decompositions. We will also introduce two new related problems, namely Weighted H-Decompositions of graphs and Monochromatic H-Decom- positions of graphs.
4-Cycle Decompositions of Graphs  [PDF]
Teresa Sousa
Open Journal of Discrete Mathematics (OJDM) , 2012, DOI: 10.4236/ojdm.2012.24024
Abstract: In this paper we consider the problem of finding the smallest number such that any graph G of order n admits a decomposition into edge disjoint copies of C4 and single edges with at most elements. We solve this problem for n sufficiently large.
Justification of public investment initiatives on water transfer systems as an instrument for water balances in Spain: the case of the Júcar–Vinalopó water transfer system  [PDF]
Martin Sevilla, Teresa Torregrosa
Agricultural Sciences (AS) , 2011, DOI: 10.4236/as.2011.24067
Abstract: One of the most controversial issues in recent years in water management has been finding a balance between available resources and water needs related to certain territories. The changes brought about by a new awareness over the need to preserve the environment, the social perception of the ownership of the river channels, the need for adjust financial costs arising from the waterworks and the compliance with European standards urgently require redesign of water supply policies in force at this time. The Júcar-Vinalopó water transfer, considered as an historic aspiration for many years in the region, has been regarded as a key element for solving the depletion of groundwater in a large area located in the southeast of the Iberian Peninsula, mainly for irrigation purposes. In this paper we present an approach to the economic aspects related to the implementation of the project, its investment and financing arrangements and the question of the subsequent management with the impact of the well-known “recovery cost principle", highlighting the current difficulties in carrying out projects of this size, due to severe limitations, as social and economic conditions of the transfer.
Phosphoinositide and phospholipid phosphorylation and hydrolysis pathways
—Organophosphate and organochlorine pesticides effects
 [PDF]

Teresa Fonovich, Gladis Magnarelli
Advances in Biological Chemistry (ABC) , 2013, DOI: 10.4236/abc.2013.33A004
Abstract:

Phospholipid and phosphoinositide phosphorylation pathways have been shown to be of crucial importance on producing lipid mediators. The earlier findings reported on lipid molecules playing roles in different metabolic pathways used to assign them the exclusive role of second messenger generators. Several researchers have recently described how direct interaction of phospholipids and phosphoinositides with molecules or organelles, without the need for producing second messenger molecules, is responsible for their mechanism of action. Organophosphate and organochlorine pesticide toxicity mechanisms have been extensively studied in relation to their well known effects on cholinesterase activities and on the alterations of electric activity in the nervous system of different organisms respectively. There is little but consistent evidence that some compounds, including in both groups of pesticides, are also able to interact with phospholipid and phosphoinositide phosphorylation pathways in several organisms and tissues. The present review consists of an actualization of basic research on phospholipid and phosphoinositide phosphorylation and hydrolysis pathways, as well as a description of some reported evidences for the effects of the above mentioned pesticides on them.

Protein phosphorylation pathways disruption by pesticides  [PDF]
Gladis Magnarelli, Teresa Fonovich
Advances in Biological Chemistry (ABC) , 2013, DOI: 10.4236/abc.2013.35050
Abstract: Phosphosites in the human proteome represent an excellent source of potential biomarkers of pesticide toxicity. In fact, experimental animal models as well as in vitro studies have revealed phosphorylation disruption associated to metabolic regulation, hormone signaling, neuronal function and differentiation, cell survival and death. Due to their estrogen-mimicking ability, pesticides are considered as prime etiological suspects of increasing tumor incidence. Evidences of alterations in the signal transduction pathways involved in the tumor progression stage of pesticides were also provided. Despite progress in understanding the effect of pesticides on the human phosphorproteome and their health outcomes, it remains a complex issue to be studied. By now, the potential impact of pesticides in epigenetic phosphorylation pathways remains poorly explored. In addition, studies involving pesticides mixtures effects are needed. This review updates and provides a comprehensive discussion on the molecular and biochemical events underlying protein phosphorylation pathway disruption caused by pesticides most frequently detected in human tissues and fluids, such as organochlorine pesticides and organophosphates. The link between epidemiological studies and experimental approaches is also considered. Future challenges, such as micro-array phosphoproteome studies to complement gene expression arrays to understand the mechanisms involved in pesticide toxicology are briefly discussed.
Charting the Course for Sustainable Small Island Tourist Development  [PDF]
Teresa L. McKee
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.43030
Abstract:

This article, Charting the Course for Sustainable Small Island Tourist Development, addresses sustainability criteria for small island tourist development drawing on the history of development in the last decade in the Bocas del Toro archipelago of the Republic of Panama in the Caribbean Sea near the border of Costa Rica. Tax deferments for the development of vacation and resort properties spurred a boom in this island locale since the late 1980’s. Tourist Law 8 of the Panamanian constitution is referenced. Sustainability criteria of water supply and availability are suggested and outer island projects are discussed. Lessons are outlined and recommendations are made for permit qualifications that promote sustainable small island tourist development.

Robert Mayer: Conservation of Energy and Venous Blood Colour  [PDF]
Teresa Rocha-Homem
Advances in Historical Studies (AHS) , 2015, DOI: 10.4236/ahs.2015.44020
Abstract: The concept of conservation and transformation of energy was proposed by the 19th century doctor, Robert Mayer. This concept derives from a clinical observation. During the 1st centennial celebrations, the medical profession posed the question of whether Mayer had indeed observed what he claimed and took as the basis of the principle of conservation of energy: if the colour of venous blood in the tropics was lighter than in colder regions, then this was a result of a higher oxygen consumption to maintain body temperature. In this paper, it was shown that, based on Mayer’s data and contemporary physiology, this observation could indeed have occurred but for a different reason.
Legal Concepts and Multilingual Contexts in Digital Information  [PDF]
Daniela Tiscornia, Maria Teresa Sagri
Beijing Law Review (BLR) , 2012, DOI: 10.4236/blr.2012.33010
Abstract: Analysis of legal documents cannot be reduced to their linguistic expression. When dealing whit legal texts a distinction should be made between the linguistic form (normative statement) and the content (norm). Norms are conceived as the interpreted meaning of linguistic contexts (partitions in a legal text, fragments of judicial decisions, etc). In the interpretative process, legal practitioners make reference to an external system of concepts that can be assumed, even if not universal, at least shared by a large social and cultural community. As a consequence, legal interpretation and legal conceptualization are strongly influenced by cultural, social and political factors and changes in meaning of legal concepts occur within a synchronic localization in different cultures and within a diachronic evolution process of the environment in which they are created. This dynamic nature of legal knowledge poses serious problems in communicating legal information, and even more in the realm of digital communication, where, in order to manage knowledge across national borders, there is a strong demand of shared vocabularies embedding a shared understanding of legal concept. This paper aims at showing how lexical/terminological resources and conceptual structures, such as ontologies, can be constructed by means of the innovative tools provided by ICT, like the Semantic Web languages, the computational linguistic and the ontology engineering techniques. Such semantic resources may have a strategic role in representing meaning evolution and in investigating social and cultural influences in linguistic uses and, as a further goal, solutions offered by ICT for bridging the gap between form and content can also provide innovative visions of theoretical issues.
Alternative Nitrogenases in Anabaena variabilis: The Role of Molybdate and Vanadate in Nitrogenase Gene  [PDF]
Teresa Thiel, Brenda S. Pratte
Advances in Microbiology (AiM) , 2013, DOI: 10.4236/aim.2013.36A011
Abstract: Anabaena variabilis ATCC 29413 has two distinct nitrogenases that function in heterocysts, a conventional Mo-nitrogenase and an alternative V-nitrogenase. Synthesis of these two enzymes was repressed in cells growing with a source of fixed nitrogen, such as ammonium; however, the V-nitrogenase was also repressed by Mo. Expression of the V-nitrogenase which was not affected by V and expression of the Mo-nitrogenase was not affected by the presence or absence of either Mo or V. In the absence of both Mo and V in an environment lacking fixed nitrogen, cells became starved for both metals; however, low levels of nitrogen fixation and slow growth persisted. A mutant lacking the V-nitrogenase was still able to grow very slowly in Mo-and V-free medium; however, loss of the Mo-nitrogenase in a nifDK1 mutant abolished the residual growth, suggesting that only the Mo-nitrogenase functioned under these conditions to support slow growth. The addition of vanadate, molybdate, or tungstate, which is transported by the molybdate transporter, to cells starved for these metals resulted in an increase in nitrogenase activity within two hours after the addition of the metal and this increase required new protein synthesis. While tungstate functioned about as well as vanadate in supporting acetylene reduction, the cells were not able to grow any better with tungstate than with no added metal. A mutant lacking the V-nitrogenase showed no increase in nitrogenase activity upon addition of tungstate, suggesting that the V-nitrogenase was able to incorporate tungstate. Tungstate was able to substitute for molybdate in repressing transcription of a Mo-transport gene, but it did not repress transcription of the vnfH gene, which was repressed by Mo. The availability of Mo and V plays an important role in controlling whether the Mo-or the V-nitrogenase is used for nitrogen fixation.
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