Input Price Variation Across Locations and a Generalized Measure of Cost Efficiency

We propose a nonparametric model for global cost minimization as a framework for optimal allocation of a firm's output target across multiple locations, taking account of differences in input prices and technologies across locations. This should be useful for firms planning production sites within a country and for foreign direct investment decisions by multi-national firms. Two illustrative examples are included. The first example considers the production location decision of a manufacturing firm across a number of adjacent states of the US. In the other example, we consider the optimal allocation of US and Canadian automobile manufacturers across the two countries.

Treatment modalities of female Operation Iraqi Freedom/Operation Enduring Freedom Veterans with posttraumatic stress disorder: A systematic review of the literature

Objective. To review professional literature regarding treatment modalities of post-traumatic stress disorder (PTSD) amongst female Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) veterans, to assess the efficacy of these treatment options, and to summarize implications of the findings from this literature. Design. Systematic review of published literature. Data sources. Medline, Pubmed, Psycinfo. Review Methods. Articles selected for the literature review pertain to the treatment options of female OIF or OEF veterans who have a diagnosis of PTSD. In addition, other relevant articles, such as articles that discuss the prevalence of the problem, access to care, and similar treatment modalities for PTSD in other war settings, were selected for background information for the review. Results. The search strategy identified 1,305 potential journal articles, taken from thorough searches in Medline, Pubmed, and Psycinfo. These articles were then imported into Refworks. Following final screening, there were 18 articles included in the systematic review and 28 articles used as background information. The remaining articles were excluded following screening of abstract and/or full text of articles. Treatment modalities presented in these trials include: Exposure Therapy (average of 68% reduction in PTSD symptoms), Imagery Rehearsal Therapy (23% reduction), Body-Oriented Therapy (57% reduction), Electroconvulsive Therapy (35% reduction), Holographic Reprocessing (47% reduction), a self-defense training program (13% reduction), Cognitive Behavioral Therapy (65% reduction) and a variety of pharmacotherapies (antipsychotics at 81% reduction, sympatholytic drug at 100% reduction). Outcomes of the studies included in this systematic review were measured by using personal assessment of whether there was a reduction in symptoms of PTSD, based on the results in each study. Conclusion. Overall, all of the treatment modalities investigated in the systematic review proved to be somewhat effective in relieving the burden of symptoms of PTSD amongst female veterans of OIF/OEF. In addition to pharmacotherapy, which had the highest reduction in PTSD symptoms, both the Exposure Therapy and the Cognitive Behavioral Therapy techniques proved to have the most positive results. As all of the therapies had a positive effect on this population, to some degree, a study needs to be done in the future to compare and contrast the efficacy of each therapy intervention when applied to a standardized population.^

TIME SERIES ANALYSIS AS INPUT FOR PREDICTIVE MODELING: PREDICTING CARDIAC ARREST IN A PEDIATRIC INTENSIVE CARE UNIT

The first manuscript, entitled "Time-Series Analysis as Input for Clinical Predictive Modeling: Modeling Cardiac Arrest in a Pediatric ICU" lays out the theoretical background for the project. There are several core concepts presented in this paper. First, traditional multivariate models (where each variable is represented by only one value) provide single point-in-time snapshots of patient status: they are incapable of characterizing deterioration. Since deterioration is consistently identified as a precursor to cardiac arrests, we maintain that the traditional multivariate paradigm is insufficient for predicting arrests. We identify time series analysis as a method capable of characterizing deterioration in an objective, mathematical fashion, and describe how to build a general foundation for predictive modeling using time series analysis results as latent variables. Building a solid foundation for any given modeling task involves addressing a number of issues during the design phase. These include selecting the proper candidate features on which to base the model, and selecting the most appropriate tool to measure them. We also identified several unique design issues that are introduced when time series data elements are added to the set of candidate features. One such issue is in defining the duration and resolution of time series elements required to sufficiently characterize the time series phenomena being considered as candidate features for the predictive model. Once the duration and resolution are established, there must also be explicit mathematical or statistical operations that produce the time series analysis result to be used as a latent candidate feature. In synthesizing the comprehensive framework for building a predictive model based on time series data elements, we identified at least four classes of data that can be used in the model design. The first two classes are shared with traditional multivariate models: multivariate data and clinical latent features. Multivariate data is represented by the standard one value per variable paradigm and is widely employed in a host of clinical models and tools. These are often represented by a number present in a given cell of a table. Clinical latent features derived, rather than directly measured, data elements that more accurately represent a particular clinical phenomenon than any of the directly measured data elements in isolation. The second two classes are unique to the time series data elements. The first of these is the raw data elements. These are represented by multiple values per variable, and constitute the measured observations that are typically available to end users when they review time series data. These are often represented as dots on a graph. The final class of data results from performing time series analysis. This class of data represents the fundamental concept on which our hypothesis is based. The specific statistical or mathematical operations are up to the modeler to determine, but we generally recommend that a variety of analyses be performed in order to maximize the likelihood that a representation of the time series data elements is produced that is able to distinguish between two or more classes of outcomes. The second manuscript, entitled "Building Clinical Prediction Models Using Time Series Data: Modeling Cardiac Arrest in a Pediatric ICU" provides a detailed description, start to finish, of the methods required to prepare the data, build, and validate a predictive model that uses the time series data elements determined in the first paper. One of the fundamental tenets of the second paper is that manual implementations of time series based models are unfeasible due to the relatively large number of data elements and the complexity of preprocessing that must occur before data can be presented to the model. Each of the seventeen steps is analyzed from the perspective of how it may be automated, when necessary. We identify the general objectives and available strategies of each of the steps, and we present our rationale for choosing a specific strategy for each step in the case of predicting cardiac arrest in a pediatric intensive care unit. Another issue brought to light by the second paper is that the individual steps required to use time series data for predictive modeling are more numerous and more complex than those used for modeling with traditional multivariate data. Even after complexities attributable to the design phase (addressed in our first paper) have been accounted for, the management and manipulation of the time series elements (the preprocessing steps in particular) are issues that are not present in a traditional multivariate modeling paradigm. In our methods, we present the issues that arise from the time series data elements: defining a reference time; imputing and reducing time series data in order to conform to a predefined structure that was specified during the design phase; and normalizing variable families rather than individual variable instances. The final manuscript, entitled: "Using Time-Series Analysis to Predict Cardiac Arrest in a Pediatric Intensive Care Unit" presents the results that were obtained by applying the theoretical construct and its associated methods (detailed in the first two papers) to the case of cardiac arrest prediction in a pediatric intensive care unit. Our results showed that utilizing the trend analysis from the time series data elements reduced the number of classification errors by 73%. The area under the Receiver Operating Characteristic curve increased from a baseline of 87% to 98% by including the trend analysis. In addition to the performance measures, we were also able to demonstrate that adding raw time series data elements without their associated trend analyses improved classification accuracy as compared to the baseline multivariate model, but diminished classification accuracy as compared to when just the trend analysis features were added (ie, without adding the raw time series data elements). We believe this phenomenon was largely attributable to overfitting, which is known to increase as the ratio of candidate features to class examples rises. Furthermore, although we employed several feature reduction strategies to counteract the overfitting problem, they failed to improve the performance beyond that which was achieved by exclusion of the raw time series elements. Finally, our data demonstrated that pulse oximetry and systolic blood pressure readings tend to start diminishing about 10-20 minutes before an arrest, whereas heart rates tend to diminish rapidly less than 5 minutes before an arrest.

Improving Cervical Cancer Nodal Boost Radiation Therapy by Quantifying Uncertainties and Exploring Advanced Radiation Therapy Modalities

Radiation therapy for patients with intact cervical cancer is frequently delivered using primary external beam radiation therapy (EBRT) followed by two fractions of intracavitary brachytherapy (ICBT). Although the tumor is the primary radiation target, controlling microscopic disease in the lymph nodes is just as critical to patient treatment outcome. In patients where gross lymphadenopathy is discovered, an extra EBRT boost course is delivered between the two ICBT fractions. Since the nodal boost is an addendum to primary EBRT and ICBT, the prescription and delivery must be performed considering previously delivered dose. This project aims to address the major issues of this complex process for the purpose of improving treatment accuracy while increasing dose sparing to the surrounding normal tissues. Because external beam boosts to involved lymph nodes are given prior to the completion of ICBT, assumptions must be made about dose to positive lymph nodes from future implants. The first aim of this project was to quantify differences in nodal dose contribution between independent ICBT fractions. We retrospectively evaluated differences in the ICBT dose contribution to positive pelvic nodes for ten patients who had previously received external beam nodal boost. Our results indicate that the mean dose to the pelvic nodes differed by up to 1.9 Gy between independent ICBT fractions. The second aim is to develop and validate a volumetric method for summing dose of the normal tissues during prescription of nodal boost. The traditional method of dose summation uses the maximum point dose from each modality, which often only represents the worst case scenario. However, the worst case is often an exaggeration when highly conformal therapy methods such as intensity modulated radiation therapy (IMRT) are used. We used deformable image registration algorithms to volumetrically sum dose for the bladder and rectum and created a voxel-by-voxel validation method. The mean error in deformable image registration results of all voxels within the bladder and rectum were 5 and 6 mm, respectively. Finally, the third aim explored the potential use of proton therapy to reduce normal tissue dose. A major physical advantage of protons over photons is that protons stop after delivering dose in the tumor. Although theoretically superior to photons, proton beams are more sensitive to uncertainties caused by interfractional anatomical variations, and must be accounted for during treatment planning to ensure complete target coverage. We have demonstrated a systematic approach to determine population-based anatomical margin requirements for proton therapy. The observed optimal treatment angles for common iliac nodes were 90° (left lateral) and 180° (posterior-anterior [PA]) with additional 0.8 cm and 0.9 cm margins, respectively. For external iliac nodes, lateral and PA beams required additional 0.4 cm and 0.9 cm margins, respectively. Through this project, we have provided radiation oncologists with additional information about potential differences in nodal dose between independent ICBT insertions and volumetric total dose distribution in the bladder and rectum. We have also determined the margins needed for safe delivery of proton therapy when delivering nodal boosts to patients with cervical cancer.

Minimum water input event for seedling emergence of three native perennial grasses of the Central Monte desert (Argentina) influenced by the effect of shade and the season of the year

In deserts, seedling emergence occurs only after precipitation threshold has been exceeded, however, the presence of trees modifies microenvironmental conditions that might affect the effectiveness of a water pulse. In the Monte desert, Prosopis flexuosa trees generate different micro-environmental conditions that might influence grass seedlings establishment. The objective of this work was: a) to know the effective minimum water input event that triggers the emergence of native perennial grass seedlings; b) to relate this fact with the effect of the shade of P. flexuosa canopy and the seasonal temperatures. Three important forage species of the Monte were studied: Pappophorum caespitosum and Trichloris crinita, with C4, and Jarava ichu, with C3 metabolism. Each season, seeds of these species were sown in pots placed at two light conditions: shade (similar to P. flexuosa cover) and open area, and with seven irrigation treatments (0, 10, 20, 30, 40, 2*10 and 3*10 mm). J. ichu did not emerge in any of the treatments. Significant seedling emergence was registered for P. caespitosum and T. crinita in shade conditions with 40 mm irrigation treatment in summer. Since 40 mm precipitation events are infrequent in the Monte, seedling emergence for these species would be restricted to exceptional rainy years. The facilitating effect of P. flexuosa shade would be important during the hot season.

Análisis de la composición y dinámica de grupos de investigación en perspectiva comparada input-ouput : Estudio de caso en Bibliotecología y Ciencia de la Información

El presente trabajo es una contribución al estudio de la composición y dinámica de los grupos de investigación en el ámbito universitario. El enfoque novedoso que plantea es una estrategia de demarcación y análisis de grupos en perspectiva comparada entre los proyectos (inputs) y las coautorías (outputs). Combina técnicas bibliométricas y de análisis de redes sociales aplicadas a un estudio de caso: el Departamento de Bibliotecología de la Universidad Nacional de La Plata, Argentina, en el periodo 2000-2009

Transformaciones territoriales y análisis geográfico en ámbitos patagónicos de montaña : La comarca andina del paralelo 42

El estudio de las transformaciones territoriales en esta parte del Sur del país obedece en especial a dos circunstancias de distinta índole. La primera vinculada a la investigación y su potencial trascendencia teórica y práctica en contextos académicos y profesionales interesados por comprender las características de la instalación humana en ámbitos sujetos a importantes cambios. La segunda responde al desenvolvimiento incierto de las comarcas andino patagónicas frente a hechos, propuestas y proyectos referentes a cuestiones de decisiva impronta regional. Se trata de territorios en plena gestación identitaria, donde es habitual lo dubitativo y confuso, aún desde perspectivas históricas y literarias, que son en las que normalmente se asientan las raíces regionales. En los recientes años '90 y en concordancia con los ajustes propios del nuevo orden mundial, se observan re-acomodamientos locales inscriptos en modalidades que obligan a la revisión profunda. Modalidades postmodernas que pueden identificarse como espacios de consumo. Es la condición cultural la que imprime nuevas estructuras espaciales de fuertes proyecciones anímicas enraizadas en lo simbólico y lo estético, donde las transformaciones se suceden a partir de una resignificación de la naturaleza. Desde allí es que se hacen planteos hipotéticos en busca de explicaciones, atendiendo a las valorizaciones que existen para con la Patagonia Andina. Aquellas que implican una preeminencia singular de los aspectos afectivos y emocionales por sobre los económicos, aunque con el turismo como el vector principal de transformación y a cuyo derredor se entremezclan situaciones conflictivas. Es ésta la dirección del análisis que busca esclarecer dudas a partir de la producción de conocimiento geográfico con sentido 'examinador' de la realidad. Fenómenos como los de dispersión, neoruralidad y fragmentación espacial, se muestran como los resultados más visibles en materia paisajística y con ello estamos ante un marco problemático y complejo. Con la sistematización de una significativa cantidad de información involucrada y una fuerte carga empírica proveniente de la convivencia profesional de varios años con la mayor parte de los problemas abordados, se presenta un aporte al cuerpo teórico de la Geografía preocupada por los ámbitos montanos, así como también su proyección hacia la explicación geográfica regional y su eventual insumo para el Planeamiento y la Gestión Territorial. Se analiza el conjunto territorial ofreciendo una perspectiva integradora en escenarios novedosos que, desde nuestra disciplina pueden abordarse con la posibilidad cierta de orientar una importante cantidad de estudios sectoriales que ya se manifiestan, en particular por requerimientos políticos. Con la Comarca Andina del Paralelo 42 en el foco del análisis, la tesis se abocó a incursionar en la realidad andino patagónica, identificando, sistematizando y valorando los conflictos de estirpe territorial como camino explicativo.

EPANET Input Files of New York tunnels and Pacific City used in a metamodel-based optimization study

Metamodels have proven be very useful when it comes to reducing the computational requirements of Evolutionary Algorithm-based optimization by acting as quick-solving surrogates for slow-solving fitness functions. The relationship between metamodel scope and objective function varies between applications, that is, in some cases the metamodel acts as a surrogate for the whole fitness function, whereas in other cases it replaces only a component of the fitness function. This paper presents a formalized qualitative process to evaluate a fitness function to determine the most suitable metamodel scope so as to increase the likelihood of calibrating a high-fidelity metamodel and hence obtain good optimization results in a reasonable amount of time. The process is applied to the risk-based optimization of water distribution systems; a very computationally-intensive problem for real-world systems. The process is validated with a simple case study (modified New York Tunnels) and the power of metamodelling is demonstrated on a real-world case study (Pacific City) with a computational speed-up of several orders of magnitude.

Transformaciones territoriales y análisis geográfico en ámbitos patagónicos de montaña : La comarca andina del paralelo 42

El estudio de las transformaciones territoriales en esta parte del Sur del país obedece en especial a dos circunstancias de distinta índole. La primera vinculada a la investigación y su potencial trascendencia teórica y práctica en contextos académicos y profesionales interesados por comprender las características de la instalación humana en ámbitos sujetos a importantes cambios. La segunda responde al desenvolvimiento incierto de las comarcas andino patagónicas frente a hechos, propuestas y proyectos referentes a cuestiones de decisiva impronta regional. Se trata de territorios en plena gestación identitaria, donde es habitual lo dubitativo y confuso, aún desde perspectivas históricas y literarias, que son en las que normalmente se asientan las raíces regionales. En los recientes años '90 y en concordancia con los ajustes propios del nuevo orden mundial, se observan re-acomodamientos locales inscriptos en modalidades que obligan a la revisión profunda. Modalidades postmodernas que pueden identificarse como espacios de consumo. Es la condición cultural la que imprime nuevas estructuras espaciales de fuertes proyecciones anímicas enraizadas en lo simbólico y lo estético, donde las transformaciones se suceden a partir de una resignificación de la naturaleza. Desde allí es que se hacen planteos hipotéticos en busca de explicaciones, atendiendo a las valorizaciones que existen para con la Patagonia Andina. Aquellas que implican una preeminencia singular de los aspectos afectivos y emocionales por sobre los económicos, aunque con el turismo como el vector principal de transformación y a cuyo derredor se entremezclan situaciones conflictivas. Es ésta la dirección del análisis que busca esclarecer dudas a partir de la producción de conocimiento geográfico con sentido 'examinador' de la realidad. Fenómenos como los de dispersión, neoruralidad y fragmentación espacial, se muestran como los resultados más visibles en materia paisajística y con ello estamos ante un marco problemático y complejo. Con la sistematización de una significativa cantidad de información involucrada y una fuerte carga empírica proveniente de la convivencia profesional de varios años con la mayor parte de los problemas abordados, se presenta un aporte al cuerpo teórico de la Geografía preocupada por los ámbitos montanos, así como también su proyección hacia la explicación geográfica regional y su eventual insumo para el Planeamiento y la Gestión Territorial. Se analiza el conjunto territorial ofreciendo una perspectiva integradora en escenarios novedosos que, desde nuestra disciplina pueden abordarse con la posibilidad cierta de orientar una importante cantidad de estudios sectoriales que ya se manifiestan, en particular por requerimientos políticos. Con la Comarca Andina del Paralelo 42 en el foco del análisis, la tesis se abocó a incursionar en la realidad andino patagónica, identificando, sistematizando y valorando los conflictos de estirpe territorial como camino explicativo.

Análisis de la composición y dinámica de grupos de investigación en perspectiva comparada input-ouput : Estudio de caso en Bibliotecología y Ciencia de la Información

El presente trabajo es una contribución al estudio de la composición y dinámica de los grupos de investigación en el ámbito universitario. El enfoque novedoso que plantea es una estrategia de demarcación y análisis de grupos en perspectiva comparada entre los proyectos (inputs) y las coautorías (outputs). Combina técnicas bibliométricas y de análisis de redes sociales aplicadas a un estudio de caso: el Departamento de Bibliotecología de la Universidad Nacional de La Plata, Argentina, en el periodo 2000-2009

Transformaciones territoriales y análisis geográfico en ámbitos patagónicos de montaña : La comarca andina del paralelo 42

El estudio de las transformaciones territoriales en esta parte del Sur del país obedece en especial a dos circunstancias de distinta índole. La primera vinculada a la investigación y su potencial trascendencia teórica y práctica en contextos académicos y profesionales interesados por comprender las características de la instalación humana en ámbitos sujetos a importantes cambios. La segunda responde al desenvolvimiento incierto de las comarcas andino patagónicas frente a hechos, propuestas y proyectos referentes a cuestiones de decisiva impronta regional. Se trata de territorios en plena gestación identitaria, donde es habitual lo dubitativo y confuso, aún desde perspectivas históricas y literarias, que son en las que normalmente se asientan las raíces regionales. En los recientes años '90 y en concordancia con los ajustes propios del nuevo orden mundial, se observan re-acomodamientos locales inscriptos en modalidades que obligan a la revisión profunda. Modalidades postmodernas que pueden identificarse como espacios de consumo. Es la condición cultural la que imprime nuevas estructuras espaciales de fuertes proyecciones anímicas enraizadas en lo simbólico y lo estético, donde las transformaciones se suceden a partir de una resignificación de la naturaleza. Desde allí es que se hacen planteos hipotéticos en busca de explicaciones, atendiendo a las valorizaciones que existen para con la Patagonia Andina. Aquellas que implican una preeminencia singular de los aspectos afectivos y emocionales por sobre los económicos, aunque con el turismo como el vector principal de transformación y a cuyo derredor se entremezclan situaciones conflictivas. Es ésta la dirección del análisis que busca esclarecer dudas a partir de la producción de conocimiento geográfico con sentido 'examinador' de la realidad. Fenómenos como los de dispersión, neoruralidad y fragmentación espacial, se muestran como los resultados más visibles en materia paisajística y con ello estamos ante un marco problemático y complejo. Con la sistematización de una significativa cantidad de información involucrada y una fuerte carga empírica proveniente de la convivencia profesional de varios años con la mayor parte de los problemas abordados, se presenta un aporte al cuerpo teórico de la Geografía preocupada por los ámbitos montanos, así como también su proyección hacia la explicación geográfica regional y su eventual insumo para el Planeamiento y la Gestión Territorial. Se analiza el conjunto territorial ofreciendo una perspectiva integradora en escenarios novedosos que, desde nuestra disciplina pueden abordarse con la posibilidad cierta de orientar una importante cantidad de estudios sectoriales que ya se manifiestan, en particular por requerimientos políticos. Con la Comarca Andina del Paralelo 42 en el foco del análisis, la tesis se abocó a incursionar en la realidad andino patagónica, identificando, sistematizando y valorando los conflictos de estirpe territorial como camino explicativo.

Análisis de la composición y dinámica de grupos de investigación en perspectiva comparada input-ouput : Estudio de caso en Bibliotecología y Ciencia de la Información

El presente trabajo es una contribución al estudio de la composición y dinámica de los grupos de investigación en el ámbito universitario. El enfoque novedoso que plantea es una estrategia de demarcación y análisis de grupos en perspectiva comparada entre los proyectos (inputs) y las coautorías (outputs). Combina técnicas bibliométricas y de análisis de redes sociales aplicadas a un estudio de caso: el Departamento de Bibliotecología de la Universidad Nacional de La Plata, Argentina, en el periodo 2000-2009

Environmental variables and multivariate seabed classification maps via k means clustering of Potter Cove, Antarctica, link to input and result files in GeoTIFF format

This study subdivides the Potter Cove, King George Island, Antarctica, into seafloor regions using multivariate statistical methods. These regions are categories used for comparing, contrasting and quantifying biogeochemical processes and biodiversity between ocean regions geographically but also regions under development within the scope of global change. The division obtained is characterized by the dominating components and interpreted in terms of ruling environmental conditions. The analysis includes in total 42 different environmental variables, interpolated based on samples taken during Australian summer seasons 2010/2011 and 2011/2012. The statistical errors of several interpolation methods (e.g. IDW, Indicator, Ordinary and Co-Kriging) with changing settings have been compared and the most reasonable method has been applied. The multivariate mathematical procedures used are regionalized classification via k means cluster analysis, canonical-correlation analysis and multidimensional scaling. Canonical-correlation analysis identifies the influencing factors in the different parts of the cove. Several methods for the identification of the optimum number of clusters have been tested and 4, 7, 10 as well as 12 were identified as reasonable numbers for clustering the Potter Cove. Especially the results of 10 and 12 clusters identify marine-influenced regions which can be clearly separated from those determined by the geological catchment area and the ones dominated by river discharge.