Noncoherent Integration for Signal Detection: Analysis Under Model Uncertainties

The performance of postdetection integration (PDI) techniques for the detection of Global Navigation Satellite Systems (GNSS) signals in the presence of uncertainties in frequency offsets, noise variance, and unknown data-bits is studied. It is shown that the conventional PDI techniques are generally not robust to uncertainty in the data-bits and/or the noise variance. Two new modified PDI techniques are proposed, and they are shown to be robust to these uncertainties. The receiver operating characteristics (ROC) and sample complexity performance of the PDI techniques in the presence of model uncertainties are analytically derived. It is shown that the proposed methods significantly outperform existing methods, and hence they could become increasingly important as the GNSS receivers attempt to push the envelope on the minimum signal-to-noise ratio (SNR) for reliable detection.

Combining ``chimie douce'' and green principles for the developing world: Improving industrial viability of photocatalytic water remediation

We highlight the need for a comprehensive, multi-disciplinary approach for the development of cost-effective water remediation methods. Combining ``chimie douce'' and green chemical principles seems essential for making these technologies economically viable and socially relevant (especially in the developing world). A comprehensive approach to water remediation will take into account issues such as nanotoxicity, chemical yield, cost, and ease of deployment in reactors. By considering technological challenges that lie ahead, we will attempt to identify directions that are likely to make photocatalytic water remediation a more global technology than it currently is. (C) 2013 Elsevier Ltd. All rights reserved

Biological sulfate reduction of a sulfate-rich industrial waste liquor using sulfate reducing bacteria

An industrial waste liquor having high sulfate concentrations was subjected to biological treatment using the sulfate-reducing bacteria (SRB) Desulfovibrio desulfuricans. Toxicity levels of different sulfate, cobalt and nickel concentrations toward growth of the SRB with respect to biological sulfate reduction kinetics was initially established. Optimum sulfate concentration to promote SRB growth amounted to 0.8 - 1 g/L. The strain of D. desulfuricans used in this study initially tolerated up to 4 -5 g/L of sulfate or 50 mg/L of cobalt and nickel, while its tolerance could be further enhanced through adaptation by serial subculturing in the presence of increasing concentrations of sulfate, cobalt and nickel. From the waste liquor, more than 70% of sulfate and 95% of cobalt and nickel could be precipitated as sulfides, using a preadapted strain of D. desulfuricans. Probable mechanisms involving biological sulfide precipitation and metal adsorption onto precipitates and bacterial cells are discussed.

An early in-situ stress signature of the AlN-Si pre-growth interface for successful integration of nitrides with (111) Si

The integration of Metal Organic Chemical Vapor Deposition (MOCVD) grown group III-A nitride device stacks on Si (111) substrates is critically dependent on the quality of the first AlN buffer layer grown. A Si surface that is both oxide-free and smooth is a primary requirement for nucleating such layers. A single parameter, the AlN layer growth stress, is shown to be an early (within 50 nm), clear (<0.5 GPa versus > 1GPa), and fail-safe indicator of the pre-growth surface, and the AlN quality required for successful epitaxy. Grain coalescence model for stress generation is used to correlate growth stress, the AlN-Si interface, and crystal quality. (C) 2013 AIP Publishing LLC.

AIM-Spice Integration of a Recursive Model for Threshold Voltage Shift in Thin Film Transistors

Non-crystalline semiconductor based thin film transistors are the building blocks of large area electronic systems. These devices experience a threshold voltage shift with time due to prolonged gate bias stress. In this paper we integrate a recursive model for threshold voltage shift with the open source BSIM4V4 model of AIM-Spice. This creates a tool for circuit simulation for TFTs. We demonstrate the integrity of the model using several test cases including display driver circuits.

Molecular Dissection of Mycobacterium tuberculosis Integration Host Factor Reveals Novel Insights into the Mode of DNA Binding and Nucleoid Compaction

Background: mIHF belongs to a subfamily of proteins, distinct from E. coli IHF. Results: Functionally important amino acids of mIHF and the mechanism(s) underlying DNA binding, DNA bending, and site-specific recombination are distinct from that of E. coli IHF. Conclusion: mIHF functions could contribute beyond nucleoid compaction. Significance: Because mIHF is essential for growth, the molecular mechanisms identified here can be exploited in drug screening efforts. The annotated whole-genome sequence of Mycobacterium tuberculosis revealed that Rv1388 (Mtihf) is likely to encode for a putative 20-kDa integration host factor (mIHF). However, very little is known about the functional properties of mIHF or the organization of the mycobacterial nucleoid. Molecular modeling of the mIHF three-dimensional structure, based on the cocrystal structure of Streptomyces coelicolor IHF duplex DNA, a bona fide relative of mIHF, revealed the presence of Arg-170, Arg-171, and Arg-173, which might be involved in DNA binding, and a conserved proline (Pro-150) in the tight turn. The phenotypic sensitivity of Escherichia coli ihfA and ihfB strains to UV and methyl methanesulfonate could be complemented with the wild-type Mtihf but not its alleles bearing mutations in the DNA-binding residues. Protein-DNA interaction assays revealed that wild-type mIHF, but not its DNA-binding variants, binds with high affinity to fragments containing attB and attP sites and curved DNA. Strikingly, the functionally important amino acid residues of mIHF and the mechanism(s) underlying its binding to DNA, DNA bending, and site-specific recombination are fundamentally different from that of E. coli IHF. Furthermore, we reveal novel insights into IHF-mediated DNA compaction depending on the placement of its preferred binding sites; mIHF promotes DNA compaction into nucleoid-like or higher order filamentous structures. We therefore propose that mIHF is a distinct member of a subfamily of proteins that serve as essential cofactors in site-specific recombination and nucleoid organization and that these findings represent a significant advance in our understanding of the role(s) of nucleoid-associated proteins.

Molecular Dissection of Mycobacterium tuberculosis Integration Host Factor Reveals Novel Insights into the Mode of DNA Binding and Nucleoid Compaction

The annotated whole-genome sequence of Mycobacterium tuberculosis indicated that Rv1388 (Mtihf) likely encodes a putative 20 kDa integration host factor (mIHF). However, very little is known about the functional properties of mIHF or organization of mycobacterial nucleoid. Molecular modeling of the mIHF three-dimensional structure, based on the cocrystal structure of Streptomyces coelicolor IHF-duplex DNA, a bona fide relative of mIHF, revealed the presence of Arg170, Arg171, and Arg173, which might be involved in DNA binding, and a conserved proline (P150) in the tight turn. The phenotypic sensitivity of Escherichia coli Delta ihfA and Delta ihfB strains to UV and methylmethanesulfonate could be complemented with the wild-type Mtihf, but not its alleles bearing mutations in the DNA-binding residues. Protein DNA interaction assays revealed that wild-type mIHF, but not its DNA-binding variants, bind with high affinity to fragments containing attB and attP sites and curved DNA. Strikingly, the functionally important amino acid residues of mIHF and the mechanism(s) underlying its binding to DNA, DNA bending, and site-specific recombination are fundamentally different from that of E. coli IHF alpha beta. Furthermore, we reveal novel insights into IHF-mediated DNA compaction depending on the placement of its preferred binding sites; mIHF promotes compaction of DNA into nucleoid-like or higher-order filamentous structures. We hence propose that mIHF is a distinct member of a subfamily of proteins that serve as essential cofactors in site-specific recombination and nucleoid organization and that these findings represent a significant advance in our understanding of the role(s) of nucleoid-associated proteins.

Biodiesel Exhaust Treatment with Dielectric Barrier Discharges Coupled with Industrial Waste Byproducts

Biodiesel run engines are gaining popularity since the last few years as a viable alternative to conventional petro-diesel based engines. In biodiesel exhaust the content of volatile organic compounds, oil mist, and mass of particulate matter is considerably lower. However, the concentration of oxides of nitrogen (NOx) is relatively higher. In this paper the biodiesel exhaust from a stationary engine is treated under controlled laboratory conditions for removal of NOx using dielectric barrier discharge plasma in cascade with adsorbents prepared from abundantly available industrial waste byproducts like red mud and copper slag. Results were compared with gamma-alumina, a commercial adsorbent. Two different dielectric barrier discharge (DBD) reactors were tested for their effectiveness under Repetitive pulses /AC energization. NOx removal as high as 80% was achieved with pulse energized reactors when cascaded with red mud as adsorbent.

Active learning in keyword search-based data integration

The problem of scaling up data integration, such that new sources can be quickly utilized as they are discovered, remains elusive: Global schemas for integrated data are difficult to develop and expand, and schema and record matching techniques are limited by the fact that data and metadata are often under-specified and must be disambiguated by data experts. One promising approach is to avoid using a global schema, and instead to develop keyword search-based data integration-where the system lazily discovers associations enabling it to join together matches to keywords, and return ranked results. The user is expected to understand the data domain and provide feedback about answers' quality. The system generalizes such feedback to learn how to correctly integrate data. A major open challenge is that under this model, the user only sees and offers feedback on a few ``top-'' results: This result set must be carefully selected to include answers of high relevance and answers that are highly informative when feedback is given on them. Existing systems merely focus on predicting relevance, by composing the scores of various schema and record matching algorithms. In this paper, we show how to predict the uncertainty associated with a query result's score, as well as how informative feedback is on a given result. We build upon these foundations to develop an active learning approach to keyword search-based data integration, and we validate the effectiveness of our solution over real data from several very different domains.

Integrating AlGaN/GaN high electron mobility transistor with Si: A comparative study of integration schemes

AlGaN/GaN high electron mobility transistor stacks deposited on a single growth platform are used to compare the most common transition, AlN to GaN, schemes used for integrating GaN with Si. The efficiency of these transitions based on linearly graded, step graded, interlayer, and superlattice schemes on dislocation density reduction, stress management, surface roughness, and eventually mobility of the 2D-gas are evaluated. In a 500 nm GaN probe layer deposited, all of these transitions result in total transmission electron microscopy measured dislocations densities of 1 to 3 x 10(9)/cm(2) and <1 nm surface roughness. The 2-D electron gas channels formed at an AlGaN-1 nm AlN/GaN interface deposited on this GaN probe layer all have mobilities of 1600-1900 cm(2)/V s at a carrier concentration of 0.7-0.9 x 10(13)/cm(2). Compressive stress and changes in composition in GaN rich regions of the AlN-GaN transition are the most effective at reducing dislocation density. Amongst all the transitions studied the step graded transition is the one that helps to implement this feature of GaN integration in the simplest and most consistent manner. (C) 2015 AIP Publishing LLC.

Incidencia de Cysticercus bovis en la matanza industrial de Nicaragua

En este trabajo, se analizó la situación existente con respecto a la Cysticercosis bovina, en la Empresa Julio Moneada Tercero, ubicada en el Km 11 carretera Norte, departamento de Managua; Esta Empresa cubre el 33% de la matanza industrial en Nicaragua. Con los datos recabados se Evaluaron: Niveles de infestación de los años 1984, 1985, 1988 y 1989; se determinó la infestación por categorías; EL departamento de mayor incidencia; Y las pérdidas económicas. Para el análisis estadístico, el método utilizado fue el de mínimos cuadrados generalizado, usando el procedimiento CATMOD del paquete statistical Analisis System. Los resultados obtenidos en el Análisis de varianza, demuestran que existen diferencias significativas entre años, con un nivel de significancia de P< 0.05 obteniéndose 1.24% de infestación global para los cuatro años, así como también existen diferencias significativas para las diferentes categorías (P< 0.05), siendo la categoría vaca (C2) la más afectada. Matagalpa resultó ser el departamento con el mayor número de animales parasitados seguido de Boaco, Managua y León. Las pérdidas económicas revelan cifras aproximadas de US$ 109,121.50 (ciento nueve mil ciento veinte y un dólares con cincuenta centavos) para el productor, adicionando a esto, las divisas no captadas por un monto aproximado de US$ 653,511.07 (seiscientos cincuenta y tres mil quinientos once dólares con siete centavos) por disminución de las exportaciones.

Residuos de plaguicidas en carne bovina de exportación en el Matadero Industrial Amerrisque

El presente trabajo se realizó en el matadero Amerrisque ubicado a la altura del km 128 carretera el Rama a 130 metros sobre e1 nivel del mar con el objetivo de evaluar los residuos de plaguicidas en carne bovina de exportación. Los datos fueron recopilados de la matanza diaria realizada en dicho matadero a partir del mes de enero de 1987 al mes de diciembre de 1992 a excepción de los meses de marzo, abril, agosto y noviembre del año 1989, de igual forma el año 1990, debido a que los registros ya para este año se encontraron incompletos. Las variables en estudio fueron: Niveles de contaminación aceptable y no aceptable para la exportación, procedencia de dichas carnes, plaguicidas que mayormente se acumulan en 1a carne y las pérdidas económicas. El procedimiento analítico se realizó por medio de una distribución de frecuencias, se hizo uso de medias como estadística descriptiva y también se determinó el rango. Como resultado del presente estudio observamos que la matanza industrial efectuada para los cinco años en estudio fue de 142,919 cabezas, de éstas 18,434 resultaron contaminada con un promedio de contaminación de 0.059 partes por millón, dejándose de percibir USA $ 10,497 dólares.

Efecto de tres periodos de suministro de alimento de retiro en broilers en la Empresa Tip-Top industrial, S.A.

En el presente estudio se evaluaron tres periodos de alimento de retiro o acabado en broilers (o, 3, 6 y 9 días antes de la matanza) el cual contiene 3,225 kcal EM/kg de alimento y 19% de proteína, ajustándose a los requerimientos nutricionales recomendados por Arbor Acres Farm Inc., (1992), en especial a la proporción energia-proteina. La evaluación tuvo lugar en la Granja Buenos Aires propiedad de la Empresa Tip-Top Industrial, S.A., con una duración de 42 días, en donde se utilizaron 800 pollos de engorde sin sexar (mixtos) de la línea Peterson-Arbor Acres de un día de edad, dichos pollos fueron distribuidos aleatoriamente en cuatro tratamientos: T1 suministro de alimento de retiro por nueve días), T2 suministro de alimento de retiro por seis días), T3, (Suministro de alimento de retiro por tres días) y T4 (testigo, con cero días de alimento de retiro), con cuatro repeticiones cada uno, distribuidos en un Diseño completamente al Azar sometidos a la prueba de rangos múltiples de Duncan. Las variables estudiadas fueron: consumo de alimento, peso vivo, ganancia de peso, conversión alimenticia, mortalidad vs viabilidad, rendimiento en la canal, análisis económico. No se encontraron diferencias significativas (P<0.05) entre los tratamientos al final del ensayo para el consumo de alimento, conversión alimenticia y costo de alimento, pero no así ara peso vivo y ganancia de peso. El porcentaje de mortalidad acumulada total fue de 2.5% y los rendimientos de la canal fueron: (90.74)T1 (88.98)T2, (85.86)T3,y (90.31)T4, Se corolo que el periodo de suministro de alimento de retiro que permitió los mejores pesos vivos, ganancias de pesos y conversiones alimenticias fue el periodo de tres días (T3), sin embargo, obtuvo el mayor consumo total para generar un peso promedio en la canal de 3.34 lbs, además, presentó el mayor costo alimenticio entre los tratamientos experimentales (T1, T2, T3) y bajo rendimiento en la canal, contrario al T1 que aunque los parámetros productivos fueron menores que el T3 obtuvo el mayor rendimiento en la canal con un menor costo alimenticio. El alimento de retiro no ejerció efecto sobre las variables estudiadas lo que demuestra que dicho alimento pueda ser una alternativa viable para disminuir costo alimenticio.

Determinación de presencia de residuos de antibióticos en carnes bovinas en el matadero industrial Nuevo Carnic, Managua

Los antibióticos imputan grandes beneficios por la eficacia antibacteriana que poseen para combatir las enfermedades que afectan a los vacunos, no obstante el uso irracional sin respetar las dosis recomendadas del producto indiscriminadamente puede tener graves consecuencias, como la resistencia bacteriana al producto que conlleva a una sobre dosificación. Tomando en cuenta la exigencia de los mercados Internacionales que cada día demandan de los productores y exportadores productos con mayor calidad de la carne en lo relacionado a los residuos de antibióticos se desarrolló el presente trabajo investigativo que se titula “Residuos de Antibióticos en carnes bovinas en el matadero Industrial Nuevo Carnic. Managua.” En el matadero se seleccionaron muestras al azar una vez por mes para determinación de residuos de antibióticos en la canal para ser realizadas en el laboratorio mediante la técnica LAST-FSIS. Mediante las cuales permitieron reconocer la ausencia de residuos de antibióticos en las canales de los años muestreados, así como también determinar la ausencia de residuos por procedencia, ya sea de departamentos o municipios de Nicaragua, que llevan animales a este matadero alcanzándose a determinar el porcentaje de animales analizándose por productores. Es saludable reconocer que a pesar de la limitada asistencia médica que reciben los productores y el alto número de productos químicos ofrecidos por las casas comerciales las canales encuentran libres de residuos de antibióticos.