Fragmentación y complejidad : análisis del cambio estructural en la economía de la región de Chicago

En este artículo, se diferencian dos dimensiones en el proceso de fragmentación: una dimensión espacial y otra funcional. Por un lado, debido a la fragmentación y a la deslocalización industrial, las economías regionales y nacionales están perdiendo encadenamientos internos. Esta fragmentación espacial determina una reducción de la complejidad de los sistemas productivos. Por otro lado, la externalización, como forma de fragmentación funcional, incrementa la densidad de transacciones y encadenamientos dentro de una economía. El impacto global de la fragmentación sobre la complejidad de los sistemas productivos nacionales y regionales depende del efecto neto de estas dos fuerzas de fragmentación. En este artículo se estudian los efectos de la fragmentación sobre la complejidad de la economía de la región de Chicago a partir de una serie de tablas input-output estimadas para el período 1978-2014, utilizando longitudes medias de propagación (APLs).__________________________________In this paper, two dimensions are differentiated within the fragmentation process: a spatial and a functional one. On the one hand, due to fragmentation and industrial relocation, regional and national economies might be losing some internal linkages. This spatial fragmentation determines a decrease in the complexity of the production systems. On the other hand, outsourcing, as a form of functional fragmentation, increases the density of transactions and linkages within an economy. The overall impact of fragmentation on the complexity of the regional and national economic systems depends on the net effect of these two fragmentation forces. In this paper, the effects of fragmentation on the complexity of the economy of the Chicago region are studied from a set of input-output tables estimated for the period 1978-2014 using Average Propagation Lengths (APLs)

Microsolvation of Mg2+, Ca2+: Strong influence of formal charges in hydrogen bond networks

A stochastic exploration of the quantum conformational spaces in the microsolvation of divalent cations with explicit consideration of up to six solvent molecules [Mg (H 2 O) n )]2+, (n = 3, 4, 5, 6) at the B3LYP, MP2, CCSD(T) levels is presented. We find several cases in which the formal charge in Mg2+ causes dissociation of water molecules in the first solvation shell, leaving a hydroxide ion available to interact with the central cation, the released proton being transferred to outer solvation shells in a Grotthus type mechanism; this particular finding sheds light on the capacity of Mg2+ to promote formation of hydroxide anions, a process necessary to regulate proton transfer in enzymes with exonuclease activity. Two distinct types of hydrogen bonds, scattered over a wide range of distances (1.35–2.15 Å) were identified. We find that in inner solvation shells, where hydrogen bond networks are severely disturbed, most of the interaction energies come from electrostatic and polarization+charge transfer, while in outer solvation shells the situation approximates that of pure water clusters

Aplicación de técnicas SIG en el estudio de evaluación de degradación de suelos. Mazarrón (Murcia)

El objetivo general de este estudio ha sido evaluar el estado actual y los cambios que se han producido en algunas características edáficas del área de Mazarrón (Murcia) en un periodo de 20 años, en relación con los procesos de degradación. Para ello se han utilizado los resultados de dos muestreos de suelos realizados en un intervalo de veinte años (1988 y 2008). Se han analizado algunas de las características edáficas que más relación tienen con la vulnerabilidad de los suelos a la erosión (Textura, Materia orgánica y Pedregosidad) y de las cuales se disponía de datos en los dos muestreos. Para la creación y análisis de la información espacial se han empleado dos Sistemas de Información Geográfica de software libre. Uno de ellos ha sido GvSIG, desarrollado por la Generalitat Valenciana y el programa GRASS. La metodología SIG empleada ha sido una herramienta fundamental para obtener la serie de capas de variables edáficas para los años 1988 y 2008. Los resultados muestran como el área de estudio es bastante vulnerable a los procesos erosivos, sobre todo por erosión hidrica y antrópica, debido a las características de sus suelos. Riesgo que se incrementaría si en futuro se abandonaran los cultivos.The main objetive of these study is to evaluate the current situation and the changes ocurred in some edaphic characteristics of the soils in the Mazarrón area (Murcia) in a twenty years period, in relation with the degradation processes. For these propose we have used the results of two soils samples carried out in a twenty years intervale (1988 and 2008). The caracteristics more related with the vulnerability of the soil erosion (texture, organic matter and stoniness) of wich we had data of the two samples were evaluated. Two Geografical Information System of free software have been used for the creation and analisis of the espacial information. One of these was GvSIG, developed by Generalitat Valenciana and GRASS programme. The GIS methodology carried out was a fundamental tool to obtain edaphic variables layers for the years 1988 and 2008. The results show how the study area is very sensible to the erosive processes, specialy by hidric and antropic erosion, because soil caracteristics. This hazard would increase in a future if the land was abandoned

Fragmentation and complexity:Analyzing structural change in the Chicago regional economy

In this paper, two dimensions are differentiated within the fragmentation process: a spatial and a functional one. On the one hand, due to fragmentation and industrial relocation, regional and national economies might be losing some internal linkages. This spatial fragmentation determines a decrease in the complexity of the production systems. On the other hand, outsourcing, as a form of functional fragmentation , increases the density of transactions and linkages within an economy. The overall impact of fragmentation on the complexity of the regional and national economic systems depends on the net effect of these two fragmentation forces. In this paper, the effects of fragmentation on the complexity of the economy of the Chicago region are studied from a set of input-output tables estimated for the period 1978-2014 using Average Propagation Lengths (APLs)

Illusions of general relativity in Brans-Dicke gravity

Contrary to common belief, the standard tenet of Brans-Dicke theory reducing to general relativity when omega tends to infinity is false if the trace of the matter energy-momentum tensor vanishes. The issue is clarified in a new approach using conformal transformations. The otherwise unaccountable limiting behavior of Brans-Dicke gravity is easily understood in terms of the conformal invariance of the theory when the sources of gravity have radiation-like properties. The rigorous computation of the asymptotic behavior of the Brans-Dicke scalar field is straightforward in this new approach.Comment: 16 pages, LaTeX, to appear in Physical Review

Diseño e implementación de los sistemas de control de un receptor solar volumétrico y de la etapa de potencia de una central eléctrica termosolar

XXIV JORNADAS DE AUTOMÁTICA (24) (24.2003.LEÓN, ESPAÑA)En este trabajo se muestran someramente los esquemas de control desarrollados e implementados para poder operar de forma automática una planta solar de receptor central, caracterizada porque la energía incidente no puede ser manipulada. El trabajo pretende mejorar los esquemas de control existentes hasta el momento y que se han utilizado para la operación de la planta TSA, aprovechando además la instalación de un nuevo receptor volumétrico en la planta. El trabajo se centra en la descripción los sistemas de control del flujo de aire a través de receptor y en los sistemas de control de la etapa de potencia al no disponer de resultados de operación en la actualidad porque el nuevo receptor volumétrico está en fase de instalación.Ministerio de Ciencia y Tecnología DPI2001-2380-C02Ministerio de Ciencia y Tecnología DPI2002-04375-C0

Predicting Recurrence and Progression in Patients with Non-Muscle-Invasive Bladder Cancer : Systematic Review on the Performance of Risk Stratification Models

BACKGROUND: Several classifications have been reported to stratify non-muscle-invasive bladder cancer (NMIBC) in risk groups according to the probability of recurrence and progression. OBJECTIVE: To systematically review the current evidence regarding risk stratification of NMIBC. METHODS: The systematic review was performed in accordance with the PRISMA statement. Studies providing data on development and/or external validation cohorts of models and risk stratification tables for recurrence and/or progression for patients with NMIBC, reporting at least one discrimination measure (AUC or C-Index) were included. RESULTS: Twenty-five studies involving 22,737 patients were included. Six classifications were identified, three of them were predictive models (EORTC, CUETO, EAU 2021) and three were based on expert opinion (EAU 2020, AUA, NCCN). A high risk of bias was present in the majority of the studies. Certain heterogenicity was found among the studies regarding adjuvant therapy, postoperative instillation or second resection. The definition of oncological outcomes was not standardized in the included studies. CUETO and EORTC scoring systems are the most validated. In general, validations showed a poor discrimination capability to predict recurrence, slightly better for progression. The EAU 2021 model overestimates the risk of progression in patients treated with BCG. Carcinoma in situ is underrepresented in all the studies analyzed. CONCLUSIONS: The existing classifications show poor discrimination capability for recurrence and possibly helpful discrimination capability for progression in NMIBC patients. These results highlight the unmet need to develop novel accurate risk models for patients with NMIBC, which could be improved with the combination of clinicopathological and molecular information

Detección de la leptospirosis renal porcina (LRP) mediante la técnica de inmuno peroxidasa (IP).

Con el propósito de estandarizar el valor diagnóstico de la técnica de inmunoperoxidasa indirecta (IP) y establecer niveles de anticuerpos anti-pomona y anti-bratislava, se recolectaron 200 muestras de riñones y sangre de 200 cerdos sacrificados en el frigorífico Guadalupe de Bogotá. En 64 (32 por ciento) riñones se observaron lesiones macroscópicas (riñón moteado blanco) y lesiones microscópicas compatibles con nefritis intersticial no supurativa en 100 tejidos renales. A todas las muestras se les aplicó la IP, para lo cual se utilizó suero policlonal de conejo contra el serovar L. pomona, resultando 62 (31 por ciento) muestras positivas. Analizados los sueros por microaglutinación (MA), se detectaron títulos entre 1:50 y 1:3200 para L. pomona en el 82.5 por ciento de los casos y para L. bratislava en el 90.5 por ciento de los mismos. Se establecieron asociaciones estadísticas mediante chi cuadrado (X2) y su fuerza se midió utilizando tasas de productos cruzados (OR), cuyos resultados fueron significativos (p igual 0.003 y OR igual 2.32) tanto para la relación entre análisis microscópico y diagnóstico por IP, como para la relación entre análisis macroscópico y diagnóstico por IP (p igual 0.001), la OR fue de 2.58. En cambio, para la relación entre los diagnósticos de IP y el serológico estas pruebas no resultaron significativa

FRW Cosmology From Five Dimensional Vacuum Brans-Dicke Theory

We follow approach of induced matter theory for 5D vacuum BD, introduce induced matter and potential in 4D hypersurfaces, and employ generalized FRW type solution. We confine ourselves to scalar field and scale factors be functions of the time. This makes the induced potential, by its definition, vanishes. When the scale factor of fifth dimension and scalar field are not constants, 5D eqs for any geometry admit a power law relation between scalar field and scale factor of fifth dimension. Hence the procedure exhibits that 5D vacuum FRW like eqs are equivalent, in general, to corresponding 4D vacuum ones with the same spatial scale factor but new scalar field and coupling constant. We show that 5D vacuum FRW like eqs or its equivalent 4D vacuum ones admit accelerated solutions. For constant scalar field, eqs reduce to usual FRW eqs with typical radiation dominated universe. For this situation we obtain dynamics of scale factors for any geometry without any priori assumption. For nonconstant scalar fields and spatially flat geometries, solutions are found to be power law and exponential ones. We also employ weak energy condition for induced matter, that allows negative/positive pressures. All types of solutions fulfill WEC in different ranges. The power law solutions with negative/positive pressures admit both decelerating and accelerating ones. Some solutions accept shrinking extra dimension. By considering nonghost scalar fields and recent observational measurements, solutions are more restricted. We illustrate that accelerating power law solutions, which satisfy WEC and have nonghost fields, are compatible with recent observations in ranges -4/3 < \omega </- -1.3151 and 1.5208 </- n < 1.9583 for dependence of fifth dimension scale factor with usual scale factor. These ranges also fulfill condition nonghost fields in the equivalent 4D vacuum BD eqs.Comment: 18 pages, 16 figures, 11 table