Constructive approximations to the q=1/2 maximum entropy distribution from redundant and noisy data

An approach adopted to consider the problem of constructing the q=1/2 maximum entropy distribution from redundant and noisy data was discussed. The advantage of this generalized approach, when dealing with very noisy data was illustrated by a numerical simulation. A strategy was proposed that evolved through different steps such as independent constraints were first preselected by recourse to a data independent technique. A backward approach was also proposed for reducing the parameters of such distributions. It was found that the sub-optimal strategies could be utilized in a broad range of situations

On the truncation of the harmonic oscillator wavepacket

We present an interesting result regarding the implication of truncating the wavepacket of the harmonic oscillator. We show that disregarding the non-significant tails of a function which is the superposition of eigenfunctions of the harmonic oscillator has a remarkable consequence: namely, there exist infinitely many different superpositions giving rise to the same function on the interval. Uniqueness, in the case of a wavepacket, is restored by a postulate of quantum mechanics

Contribución al estudio litológico de los materiales empleados en monumentos de Córdoba de distintas épocas

En este trabajo se estudian los diferentes tipos de materiales de construcción en monumentos de Córdoba durante distintas épocas y culturas. Se han utilizado las técnicas habituales para la determinación mineralógica, química , petroestructural, etc. Los materiales más empleados son las biocalcarenitas del Mioceno. También se han empleado calizas cámbricas, calizas del Titónico, mármoles, granitos, esquistos, ladrillos, tierra prensada, etc. Se citan algunos monumentos realizados en las épocas: romana, árabe, s. XIII al XIX y s. XX.This work studies the different types of construction materials in monuments in Cordova during different eras and cultures. Usual techniques have been used to determine mineralogical, chemical and petrostructural elements, etc. The most used materials are biocalcarenites from the Miocene period. Other materials include Cambrian limestone, Tithonian limestone, marble, granite, slate, bricks, pressed earth, etc. Monuments are cited from Roman and Arabic eras, and from the 8th to the 19th and 20th century

Mineralogical and textural characterization of Tartessian ceramics from Ategua (Córdoba, Spain)

El cerro de Teba situado en la Depresión del Guadalquivir, provincia de Córdoba (España), constituye uno de los yacimientos arqueológicos más interesantes de la época tartésica. En la falda de la colina de Ategua, se han encontrado restos prerromanos (precoloniales, tartesicos e ibéricos) con algunas estructuras de enterramiento y una gran riqueza de piezas cerámicas. Cerámicas de época tartésica hechas a torno (fases II y III “orientalizantes”) son las que se estudian en este trabajo. Se ha estudiado la mineralogía, composición química y la textura de estas piezas para obtener información sobre el posible origen de las materias primas utilizadas en la fabricación de las cerámicas. Algunos minerales así como los restos de fósiles son propios de ciertos ambientes, y su detección en las cerámicas permite abordar el origen de las materias primas con que se elaboraron las piezas. Determinar el origen es siempre uno de los objetivos que se plantea en este tipo de estudios, ya que los datos sobre las piezas y el entorno ayudan a abordar el problema de la autóctonía o aloctonía de las cerámicasTeba hill, located in the Guadalquivir depression (Córdoba, Spain), is one of the most interesting archaeological deposits from the Tartessian period. A number of pre-Roman (pre-colonial, Tartessian and Iberian) remains including some burial structures and a wealth of ceramic pieces have been found on the skirt of the Ategua hill. In this work, have been studied wheel-thrown ceramic pieces from Phases II and III (orientalizing). The mineralogical characteristics, chemical composition and texture of the pieces were used to identify the potential origin of the raw materials used in their production. Some minerals are as well as fossil remains in fact typical of specific environments, so their presence in a ceramic piece can help trace the origin of its components. Elucidating the origin of such materials is a common objective in these studies since accurate information obtained from ceramic pieces and their environment can help one determine whether they are autochthonous or allochthonous

Solvent Extraction Reagent Entrainment Effects On Zinc Electrowinning From Waste Oxide Leach Solutions

A considerable quantity of metal-containing waste oxide is generated by the primary metal industry, and under increased environmental regulation, treatment of these wastes has become viable. Hydrometallurgical processing is often appropriate and one potential treatment process for zinc oxide wastes involves leaching the oxide with an acid, purifying by a solvent extraction operation, and recovering metallic zinc by electrowinning the purified leach solution. The purification stage is frequently critical and the introduction of a solvent extraction organic reagent into the flowsheet can be detrimental to downstream processes. The object of this study was to determine the effect of organics, entrained during solution purification, on the zinc electrowinning efficiency. Zinc solvent extraction / electrowinning studies were made using di-2-ethylhexyl phosphoric acid (D2EHPA), diluted with kerosene, as the organic extractant. The stripping of the zinc from the organic phase was achieved using spent electrolyte solution. Multiple stages of zinc solvent extraction tests were performed to produce a strong acid electrolyte suitable for electrowinning tests. The entrainment of the organic extractant, from the solvent extraction stage, in the loaded spent electrolyte was found to significantly affect the current efficiency, and to change the zinc deposit morphology and orientation with concurrent modifications to the polarization behavior of the system being noted. Purification of the contaminated electrolyte with activated carbon improved the current efficiency and deposit morphology and decreased the polarization to acceptable levels. The conclusions are that the detrimental effects of entrained organic can be eliminated, and that solvent extraction processing is a viable method for the treatment of zinc containing waste oxides. © 1992

From cardinal spline wavelet bases to highly coherent dictionaries

Wavelet families arise by scaling and translations of a prototype function, called the mother wavelet. The construction of wavelet bases for cardinal spline spaces is generally carried out within the multi-resolution analysis scheme. Thus, the usual way of increasing the dimension of the multi-resolution subspaces is by augmenting the scaling factor. We show here that, when working on a compact interval, the identical effect can be achieved without changing the wavelet scale but reducing the translation parameter. By such a procedure we generate a redundant frame, called a dictionary, spanning the same spaces as a wavelet basis but with wavelets of broader support. We characterize the correlation of the dictionary elements by measuring their 'coherence' and produce examples illustrating the relevance of highly coherent dictionaries to problems of sparse signal representation

A competitive scheme for storing sparse representation of X-Ray medical images

A competitive scheme for economic storage of the informational content of an X-Ray image, as it can be used for further processing, is presented. It is demonstrated that sparse representation of that type of data can be encapsulated in a small file without affecting the quality of the recovered image. The proposed representation, which is inscribed within the context of data reduction, provides a format for saving the image information in a way that could assist methodologies for analysis and classification. The competitiveness of the resulting file is compared against the compression standards JPEG and JPEG200

Biocalcarenites as construction materials in Santa Marina de Aguas Santas Church at Cordoba, Spain

Para la caracterización litológica y determinación del grado de alteración de los materiales pétreos se han empleado las siguientes técnicas: difracción de rayos X (método del polvo), microscopía petrográfica (sobre lámina delgada) y microscopía de barrido con EDS (energía dispersiva de rayos X), para determinar la composición química. El estado de degradación del material pétreo se ha cuantificado a partir del índice químico de alteración (CIW). Se han realizado cartografías sobre la fachada oeste: a) de las litologías presentes y b) de los diferentes tipos de alteración observados. La comparación de muestras del edificio con las de antiguas canteras ha permitido identificar la del Naranjo como la posible cantera de origen.This study consisted in characterizing the materials used to build Santa Marina de Aguas Santas Church at Cordoba and locating the original quarries. The techniques used in the lithological and chemical characterization included XRD, petrographic microscopy and electron dispersive scanning microscopy. The chemical index of weathering (CIW) was used to quantify the state of stone decay. The lithology and different types of alterations observed were mapped. A comparison of the material on the building to ancient quarries identified “Naranjo” as the possible site where the stone was originally quarried

Site-to-site interdomain communication may mediate different loss-of-function mechanisms in a cancer-associated NQO1 polymorphism

Disease associated genetic variations often cause intracellular enzyme inactivation, dysregulation and instability. However, allosteric communication of mutational effects to distant functional sites leading to loss-of-function remains poorly understood. We characterize here interdomain site-to-site communication by which a common cancer-associated single nucleotide polymorphism (c.C609T/p.P187S) reduces the activity and stability in vivo of NAD(P)H:quinone oxidoreductase 1 (NQO1). NQO1 is a FAD-dependent, two-domain multifunctional stress protein acting as a Phase II enzyme, activating cancer pro-drugs and stabilizing p53 and p73a oncosuppressors. We show that p.P187S causes structural and dynamic changes communicated to functional sites far from the mutated site, affecting the FAD binding site located at the N-terminal domain (NTD) and accelerating proteasomal degradation through dynamic effects on the C-terminal domain (CTD). Structural protein:protein interaction studies reveal that the cancer-associated polymorphism does not abolish the interaction with p73a, indicating that oncosuppressor destabilization largely mirrors the low intracellular stability of p.P187S. In conclusion, we show how a single disease associated amino acid change may allosterically perturb several functional sites in an oligomeric and multidomain protein. These results have important implications for the understanding of loss-of-function genetic diseases and the identification of novel structural hot spots as targets for pharmacological intervention

Frames:a maximum entropy statistical estimate of the inverse problem

A maximum entropy statistical treatment of an inverse problem concerning frame theory is presented. The problem arises from the fact that a frame is an overcomplete set of vectors that defines a mapping with no unique inverse. Although any vector in the concomitant space can be expressed as a linear combination of frame elements, the coefficients of the expansion are not unique. Frame theory guarantees the existence of a set of coefficients which is “optimal” in a minimum norm sense. We show here that these coefficients are also “optimal” from a maximum entropy viewpoint