P-wave Pairing and Colossal Magnetoresistance in Manganese Oxides

We point out that the existing experimental data of most manganese oxides show the {\sl frustrated} p-wave superconducting condensation in the ferromagnetic phase in the sense that the superconducting coherence is not long enough to cover the whole system. The superconducting state is similar to the $A_{1}$ state in superfluid He-3. The sharp drop of resistivity, the steep jump of specific heat, and the gap opening in tunneling are well understood in terms of the p-wave pairing. In addition, colossal magnetoresistance (CMR) is naturally explained by the superconducting fluctuations with increasing magnetic fields. The finite resistivity may be due to some magnetic inhomogeneities. This study leads to the possibility of room temperature superconductivity.Comment: LaTex, 14 pages, For more information, please send me an e-mail. e-mail adrress : [email protected]

Non-user benefits emanating from enhanced water flow to the Yala Protected Area Complex

Water is a multiple use resource. Increasing scarcity and competition from various sectors is an important dimension to be considered in its management. Understanding the value of water to different water uses is, therefore, necessary to assist decision-making in water allocation among sectors. Although water used in agriculture can be valued using production function approaches, such direct valuation methods are not available for the environmental uses of water. This paper uses non-market valuation methods to estimate the economic value of a committed flow through a unique ecosystem, the Yala Protected Area Complex (YPC). The Yala Protected Area Complex is an important wildlife refuge situated in south-eastern Sri Lanka. Its large land extent, undisturbed nature, and abundance and diversity of fauna contribute to its uniqueness. The fact that the YPC is also the most visited national park in Sri Lanka is partially a result of this uniqueness. However, maintenance of the park’s ecosystem depends on the flow of the Menik Ganga. This flow is regulated by the Veheragala Reservoir Project, and there is now discussion of reducing flow into the park by about half of the current level. The proposed plan ensures dry season flow into the YPC and, therefore, has been deemed acceptable. However, there is a possibility that farmers will demand further water releases during the dry season which could in turn endanger the planned downstream water releases. So there is a potential trade-off between environmental and irrigation uses of water. A willingness to pay (WTP) survey was conducted in ten districts in Sri Lanka during the fourth quarter of 2008 to estimate the WTP of the general population of the country towards maintaining this important environmental resource. In the hypothetical market presented, participants were told of the need for financial contributions from the general public to ensure the release of a minimum downstream flow commitment of 50 MCM. Participants were also informed of how this flow would enhance the ecosystem of the YPC. A single bound dichotomous choice contingent valuation approach was used as the elicitation format. Nonobligatory voluntary contributions were solicited towards a trust fund that could be used to ensure release of the required quantity of water downstream during dry months. According to the results of a binary logistic regression, income, age, and religious attachments are important factors affecting the decision to contribute to environmental flow maintenance to the YPC. Sixty-five percent of respondents were willing to pay something to ensure the maintenance of an adequate environmental flow in the YPC. The estimated mean WTP for water releases to enhance the YPC is Sri Lankan Rupees (SLR) 435 per year. Over the requested payment horizon of 10 years, the present value of aggregate WTP from the Sri Lankan population to enhance the ecosystem of the YPC is SLR 12 billion. This quantity greatly surpasses the present value of net benefits from rice farming estimated at SLR 0.64 billion, which would be generated if the same quantity of water was used for irrigation for 10 years (assuming current prices and input intensities). Thus, there is a clear opportunity for national welfare gain by ensuring adequate flow in YPC.Length: pp.37-47Water useMultiple useWildlifeHabitatsEcosystemsIrrigation waterWater allocation

Non-user benefits emanating from enhanced water flow to Yala Protected Area Complex. Abstract only

EcosystemsWater resource managementMultiple useDecision makingWater allocationEnvironmental flows

On the relevance of chaos for halo stars in the Solar Neighbourhood

We show that diffusion due to chaotic mixing in the Neighbourhood of the Sun may not be as relevant as previously suggested in erasing phase space signatures of past Galactic accretion events. For this purpose, we analyse Solar Neighbourhood-like volumes extracted from cosmological simulations that naturally account for chaotic orbital behaviour induced by the strongly triaxial and cuspy shape of the resulting dark matter haloes, among other factors. In the approximation of an analytical static triaxial model, our results show that a large fraction of stellar halo particles in such local volumes have chaos onset times (i.e., the timescale at which stars commonly associated with chaotic orbits will exhibit their chaotic behaviour) significantly larger than a Hubble time. Furthermore, particles that do present a chaotic behaviour within a Hubble time do not exhibit significant diffusion in phase space.Comment: 20 pages, 16 figures. Accepted for publication in MNRA

Infinitesimals without Logic

We introduce the ring of Fermat reals, an extension of the real field containing nilpotent infinitesimals. The construction takes inspiration from Smooth Infinitesimal Analysis (SIA), but provides a powerful theory of actual infinitesimals without any need of a background in mathematical logic. In particular, on the contrary with respect to SIA, which admits models only in intuitionistic logic, the theory of Fermat reals is consistent with classical logic. We face the problem to decide if the product of powers of nilpotent infinitesimals is zero or not, the identity principle for polynomials, the definition and properties of the total order relation. The construction is highly constructive, and every Fermat real admits a clear and order preserving geometrical representation. Using nilpotent infinitesimals, every smooth functions becomes a polynomial because in Taylor's formulas the rest is now zero. Finally, we present several applications to informal classical calculations used in Physics: now all these calculations become rigorous and, at the same time, formally equal to the informal ones. In particular, an interesting rigorous deduction of the wave equation is given, that clarifies how to formalize the approximations tied with Hook's law using this language of nilpotent infinitesimals.Comment: The first part of the preprint is taken directly form arXiv:0907.1872 The second part is new and contains a list of example

Water Conservation with Urban Landscape Plants

Water shortages are a common problem in much of the southwest. Increasing urbanization and increasing population places greater demands on dwindling water supplies. Over half of the water used in urban areas of the southwest is used in the irrigation of landscapes. To help cope with increased urban water demands and low water supplies, research was conducted from March 1981 to July 1983 at The Texas Agricultural Experiment Station at Dallas to gain information relative to consumptive water use by native and non-native landscape plants. Twenty weighing lysimeters were constructed and installed and plants established in the lysimeters and adjacent areas. The lysimeters were made from 0.6 X 0.9 m undisturbed cores of Austin silty clay soil. Plants used in the lysimeter study were buffalograss, St. Augustine grass, cenizo, boxwood and Texas barberry. All plants are native to Texas except boxwood and St. Augustine grass. Four lysimeters were planted to each plant type. This allowed two moisture levels and two replications of each plant type. There was no difference in water use by St. Augustine grass and buffalo grass during the year of establishment. Daily water use ranged from 0.49 to 0.08 cm per day but was generally 50% class A pan evaporation. St. Augustine grass used 0.03 cm/day more water than buffalo grass during 1982. -Irrigation treatments used in 1982 did not influence water use by either grass type but buffalo grass retained higher quality under dry treatment (irrigated at 0.40 bar moisture tension) than St. Augustine grass. Water use from May to July 1983 was highest (of all treatments) by St. Augustine grass when irrigated at 0.25 bar soil moisture tension at 76 cm depth and lowest (of all treatments) by buffalograss when irrigated at 0.75 bar soil moisture tension at 76 cm depth. Application of 50% class A pan evaporation each week appears to be an acceptable guideline for irrigation of either turfgrass but research should be conducted over a longer time period to obtain more specific guidelines for each grass species. Water use by shrubs in lysimeters was variable and not influenced by plant type during the period of establishment (Fall 1981). During 1982 water use was influenced more by plant size than by specie or water level. Cenizo had much faster growth rate than the other shrubs in the study. Water use by container grown plants indicated that cenizo had higher water use efficiency than boxwood or Indian Hawthorn. Water use was determined for several native shrubs and of the ones compared, Texas barberry appeared to have the most promise for use in water conserving landscapes

Optimizing the computation of overriding

We introduce optimization techniques for reasoning in DLN---a recently introduced family of nonmonotonic description logics whose characterizing features appear well-suited to model the applicative examples naturally arising in biomedical domains and semantic web access control policies. Such optimizations are validated experimentally on large KBs with more than 30K axioms. Speedups exceed 1 order of magnitude. For the first time, response times compatible with real-time reasoning are obtained with nonmonotonic KBs of this size

RNA mediated trans-activation: its therapeutic potential in anaplastic thyroid cancer

RNA mediated trans-Activation is a proposed mechanism involved in the setting of the epigenetic state of chromatin. It has been studied first in Drosophila melanogaster where it seems that at least some transcribed loci are marked as transcriptionally active by their own transcripts. This effect acts in trans and in some cases could give rise to a transgenerational paramutational-like effect. This work studies RNA mediated trans-activation in the light of one of its possible applications, specifically its use as a therapeutic strategy for the incurable and highly aggressive ATC (anaplastic thyroid cancer). We explore the possibility to reactivate the Thyroid specific NIS (Natrium-Iodine symport) via the expression of ncRNAs with sequence homology with transcripts from the NIS coding locus itself. This work suggests that RNA trans-activation is a conserved mechanism and it may be used in human to manipulate the gene expression