bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direccionamiento automático de antenas en estaciones terrenas de seguimiento a picosatelites
Authors: Espindola Jorge , Ferro Escobar Roberto , Mesa Lara Jairo Alonso 
Published: March 2015

El presente artículo muestra los resultados de un proyecto desarrollado en el grupo de investigación en Informática, Electrónica y Comunicaciones (INFELCOM) de la Universidad Pedagógica y Tecnológica de Colombia (UPTC). El objetivo fue desarrollar un software que, acoplado al hardware propio de la estación terrena, ubicada en la UPTC de la ciudad de Tunja (Bo-yacá, Colombia) y a un software de predicción de órbita [1] desarrollado por INFELCOM, controle en forma automática el posicionamiento de las antenas de dicha estación. Para el control de posicionamiento se emplearon las técnicas de Inteligencia Artificial (IA), algoritmos genéticos de selección y algoritmos de enfriamiento simulado.
Método para el reconocimiento automático de respuestas abiertas, cortas e irregulares en cuestionarios de completar espacios
Authors: Rojas Sergio 
Published: March 2015

La evaluación de estudiantes en ambientes educativos virtuales como Moodle, se realiza mediante preguntas cerradas (por ejemplo, de selección múltiple) cuyas respuestas pueden ser calificadas automáticamente sin necesidad de intervención humana. Los cuestionarios de preguntas abiertas con espacios para rellenar permiten al estudiante escribir variantes que pueden diferir de la respuesta esperada debido a errores de ortografía o tipográficos, siendo inviable calificarlas automáticamente mediante comparación exacta. En este artículo se propone una técnica que utiliza una versión adaptada de un algoritmo de comparación de cadenas de caracteres, y que podría realizar la evaluación automática de este tipo de preguntas.Se presentan resultados en 2 escenarios. En el primero, se calificaron respuestas irregulares de una sola palabra en un cuestionario de seguridad en internet; las variantes fueron reconocidas correctamente con un 99 % de exactitud y nivel de tolerancia de corrección de máximo dos letras. En el segundo, se evaluaron respuestas abiertas cortas a cuestionarios de programación de computadores, es decir, pequeños bloques de código de lenguaje de computador. Se calificaron 21 respuestas escritas por estudiantes de un curso real de programación, sin considerar particularidades como nomenclatura para variables o funciones, y utilizando una tolerancia de corrección de hasta 20 % de la longitud de la respuesta libre. El método reconoció 12 respuestas como probablemente correctas con expresiones mal formadas o incompletas pero fácilmente subsanables. Esta calificación fue satisfactoriamente corroborada por un experto humano. También se discuten otros resultados, así como posibles mejoras de la técnica propuesta.
Influence of the void ratio and the confining on the static liquefaction in slopes in shangi sand
Authors: Ramos Cañón Alfonso Mariano 
Published: March 2015

Se presenta un estudio numérico del inicio de la licuación estática en taludes, bajo condiciones no drenadas de carga, basado en un criterio de inestabilidad general para suelos elastoplás-ticos, fundamentado en el concepto de pérdida de controlabilidad. Se aplica el criterio al caso de carga axisimétrica, para detectar el punto de inicio de licuación con un modelo elastoplástico para arenas. Se comparan los resultados numéricos con evidencia experimental, encontrando un buen nivel de concordancia. Se presenta un estudio cuantitativo de la influencia de la presión media, relación de vacíos y la anisotropía inicial de esfuerzos sobre el inicio de la licuación en la arena de Changi. Se concluye que: a) el ángulo de fricción movilizado al inicio de la licuación no es una propiedad del material, sino que es una variable de estado; b) a pesar de las múltiples variables involucradas en el proceso de generación de inestabilidad no drenada, el estado de esfuerzos en el inicio de la licuación estática se puede representar convenientemente por una relación lineal entre Aq/p0 y r|0. Esta representación gráfica se puede usar en la práctica de la ingeniería geotécnica para cuantificar un margen de seguridad contra licuación estática de un talud arenoso.
Developers’ Incentives and Open-Source Software Licensing: GPL vs BSD
Authors: Atal Vidya , Shankar Kameshwari 
Published: March 2015

Abstract
One of the puzzling aspects of open-source software (OSS) development is its public good nature. Individual developers contribute to developing the software, but do not hold the copyright to appropriate its value. This raises questions regarding motives behind such effort. We provide an integrated model of developers’ incentives to describe OSS development and compare restrictive OSS licenses that force all modifications to be kept open with non-restrictive OSS licenses that allow proprietary ownership of modified works. Different incentives govern effort provision at different stages of the software development process. We show that open-source licenses can provide socially valuable software when a proprietary license fails to do so. We also show that restrictive OSS licenses generate greater effort provision in the design stage of software development relative to non-restrictive licenses. Endogenizing licensing choice, we find that a project leader chooses a non-restrictive OSS license if reputational concerns drive developers’ incentives, a proprietary license when there is a large population of users in the market and a restrictive OSS license if user population is small but reputational benefit is high. Our results resonate well with empirical findings and suggest additional testable implications about the relationship between licensing and software project characteristics. Finally, we also find that the market under-provides restrictive OSS licenses relative to the efficient level, suggesting the need for subsidizing restrictive licenses in some cases.
System Identification and Control of a Biotrickling Filter
Authors: Abdel-Jabbar Nabil , Ahmed Wasim , Shareefdeen Zarook 
Published: March 2015

Abstract
This paper studies empirical modeling and control of a biotrickling filter (BTF) used for air pollution control. Step response transfer function (TF) with first-order-plus-time-delay model and steady-state artificial neural network (NN) model were developed for BTF based on input–output (I/O) data obtained from simulation of a rigorous model. These simple models offer fast predictions compared to the rigorous model and render control implementation for BTF feasible. Gas velocity and inlet concentration of hydrogen sulfide (H2S) (target pollutant) were considered as the main process inputs while outlet concentration of H2S was selected as the BTF performance variable (output). The TF and NN models fitted well with the I/O data and the resulting regression coefficient values were above 0.97. Different simulations with the fitted NN model were performed and compared with the rigorous model data at steady state. The NN model perfectly captured the steady-state behavior of the BTF process. Two control strategies were implemented, namely proportional–integral/feedback control and model predictive control, also known as receding-horizon control. The controllers were based on the fitted TF model representation of BTF under study. For the control structure, gas velocity, inlet concentration, and outlet concentration were selected as manipulated, disturbance and controlled variables, respectively. Through set-point and disturbance change tests, it was observed that the model predictive controller offered superior set-point tracking capabilities while the feedback controller showed better control in dealing with disturbances. However, both controllers provided adequate control in general.
Natural mineral-rich water ingestion improves hepatic and fat glucocorticoid-signaling and increases sirtuin 1 in an animal model of metabolic syndrome
Authors: Pereira Cidália D. , Severo Milton , Neves Delminda , Ascensão António , Magalhães José , Guimarães João T. , Monteiro Rosário , Martins Maria João 
Published: March 2015

Abstract

Background: We recently reported protection against metabolic syndrome (MetSyn) induction and endothelial dysfunction by natural mineral-rich water intake in fructose-fed Sprague-Dawley rats. As glucocorticoids are critical to MetSyn development, we aimed to further characterize the beneficial effects of mineral-rich water intake in that animal model, by assessing relevant effectors in glucocorticoid-signaling in liver and subcutaneous (SCAT) and visceral (VAT) adipose tissues, sites with a central role in metabolic (dys)regulation.

Materials and methods: Adult male rats had free access to standard diet and different drinking solutions (8 weeks): a) tap water (CONT), b) 10% fructose/tap water (FRUCT) or c) 10% fructose/mineral-rich water (FRUCTMIN). 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), glucocorticoid receptor (GR), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1-α) and sirtuin 1 (Sirt1) tissue protein expressions were evaluated by Western blot. Plasma corticosterone (ELISA) and non-esterified fatty acids (NEFA) levels were quantified spectrophotometrically.

Results: Expectedly, Sirt1 and PGC1-α significantly decreased in liver, 11β-HSD1 tended to increase in VAT and tended to decrease in liver and SCAT, and plasma corticosterone tended to increase in FRUCT vs. CONT. Mineral-rich water showed a trend towards a reduction of these fructose effects and significantly increased hepatic Sirt1 vs. CONT and FRUCT. GR significantly increased in VAT and plasma NEFA strongly tended to increase in FRUCTMIN vs. CONT and FRUCT.

Conclusions: Glucocorticoid-signaling was different among SCAT and VAT and also in liver. Mineral-rich water modulation of fructose effects on glucocorticoid-signaling and Sirt1 underlines the better metabolic profile found earlier.
Adipose tissue, obesity and adipokines: role in cancer promotion
Authors: Booth Andrea , Magnuson Aaron , Fouts Josephine , Foster Michelle 
Published: March 2015

Abstract
Adipose tissue is a complex organ with endocrine, metabolic and immune regulatory roles. Adipose depots have been characterized to release several adipocytokines that work locally in an autocrine and paracrine fashion or peripherally in an endocrine fashion. Adipocyte hypertrophy and excessive adipose tissue accumulation, as occurs during obesity, dysregulates the microenvironment within adipose depots and systemically alters peripheral tissue metabolism. The term “adiposopathy” is used to describe this promotion of pathogenic adipocytes and associated adipose – elated disorders. Numerous epidemiological studies confirm an association between obesity and various cancer forms. Proposed mechanisms that link obesity/adiposity to high cancer risk and mortality include, but are not limited to, obesity-related insulin resistance, hyperinsulinemia, sustained hyperglycemia, glucose intolerance, oxidative stress, inflammation and/or adipocktokine production. Several epidemiological studies have demonstrated a relationship between specific circulating adipocytokines and cancer risk. The aim of this review is to define the function, in normal weight and obesity states, of well-characterized and novel adipokines including leptin, adiponectin, apelin, visfatin, resistin, chemerin, omentin, nesfatin and vaspin and summarize the data that relates their dysfunction, whether associated or direct effects, to specific cancer outcomes. Overall research suggests most adipokines promote cancer cell progression via enhancement of cell proliferation and migration, inflammation and anti-apoptosis pathways, which subsequently can prompt cancer metastasis. Further research and longitudinal studies are needed to define the specific independent and additive roles of adipokines in cancer progression and reoccurrence.
Heat shock proteins in obesity: links to cardiovascular disease
Authors: Habich Christiane , Sell Henrike 
Published: March 2015

Abstract
Adipose tissue expansion is associated with adipocyte dysfunction and increased inflammatory processes. In the obese state, adipose tissue is characterized by an impaired intracellular stress defense system and dysbalanced heat shock response. Several members of the heat shock protein (HSP) family have been identified as novel adipokines released upon cellular stress, which might be a molecular link from adipose tissue inflammation to the cardiovascular system. Therefore, this review aims at summarizing and discussing our recent knowledge on HSPs in relation to obesity and their potential links to cardiovascular disease. Of particular importance/interest are two members of the HSP family, HSP60 and heme oxygenase 1 (HO-1), which have been well described as adipokines, and studied in the context of obesity and cardiovascular disease. HSP60 is regarded as a novel molecular link between adipose tissue inflammation and obesity-associated insulin resistance. The role of HO-1 induction in the obese state is well-documented, but a causal relationship between increased HO-1 levels and obesity-associated metabolic diseases is still controversial. Both HSP60 and HO-1 are also forthcoming targets for the treatment of cardiovascular disease, and the current knowledge will also be discussed in this review.
Adipose tissue dysfunction and its effects on tumor metabolism
Authors: Diedrich Jonathan , Gusky Halina Chkourko , Podgorski Izabela 
Published: March 2015

Abstract
Growing by an alarming rate in the Western world, obesity has become a condition associated with a multitude of diseases such as diabetes, metabolic syndrome and various cancers. Generally viewed as an abnormal accumulation of hypertrophied adipocytes, obesity is also a poor prognostic factor for recurrence and chemoresistance in cancer patients. With more than two-thirds of the adult population in the United States considered clinically overweight or obese, it is critical that the relationship between obesity and cancer is further emphasized and elucidated. Adipocytes are highly metabolically active cells, which, through release of adipokines and cytokines and activation of endocrine and paracrine pathways, affect processes in neighboring and distant cells, altering their normal homeostasis. This work will examine specifically how adipocyte-derived factors regulate the cellular metabolism of malignant cells within the tumor niche. Briefly, tumor cells undergo metabolic pressure towards a more glycolytic and hypoxic state through a variety of metabolic regulators and signaling pathways, i.e., phosphoinositol-3 kinase (PI3K), hypoxia-inducible factor-1 alpha (HIF-1α), and c-MYC signaling. Enhanced glycolysis and high lactate production are hallmarks of tumor progression largely because of a process known as the Warburg effect. Herein, we review the latest literature pertaining to the body of work on the interactions between adipose and tumor cells, and underlining the changes in cancer cell metabolism that have been targeted by the currently available treatments.
Visceral adiposopathy: a vascular perspective
Authors: Farb Melissa G. , Gokce Noyan 
Published: March 2015

Abstract
Obesity has emerged as one of the most critical health care problems globally that is associated with the development of insulin resistance, type 2 diabetes mellitus, metabolic dysfunction and cardiovascular disease. Central adiposity with intra-abdominal deposition of visceral fat, in particular, has been closely linked to cardiometabolic consequences of obesity. Increasing epidemiological, clinical and experimental data suggest that both adipose tissue quantity and perturbations in its quality termed “adiposopathy” contribute to mechanisms of cardiometabolic disease. The current review discusses regional differences in adipose tissue characteristics and highlights profound abnormalities in vascular endothelial function and angiogenesis that are manifest within the visceral adipose tissue milieu of obese individuals. Clinical data demonstrate up-regulation of pro-inflammatory and pro-atherosclerotic mediators in dysfunctional adipose tissue that may support pathological vascular changes not only locally in fat but also in multiple organ systems, including coronary and peripheral circulations, potentially contributing to mechanisms of obesity-related cardiovascular disease.
Molecular cues on obesity signals, tumor markers and endometrial cancer
Authors: Daley-Brown Danielle , Oprea-Ilies Gabriela M. , Lee Regina , Pattillo Roland , Gonzalez-Perez Ruben R. 
Published: March 2015

Abstract
Tumor markers are important tools for early diagnosis, prognosis, therapy response and endometrial cancer monitoring. A large number of molecular and pathologic markers have been described in types I and II endometrial cancers, which has served to define the main oncogenic, epidemiological, genetic, clinical and histopathological features. Ongoing attempts to stratify biological markers of endometrial cancer are presented. However, data on changes in tumor marker profiles in obesity-related endometrial cancer are scarce. Obesity is a pandemic in Western countries that has an important impact on endometrial cancers, albeit through not very well-defined mechanisms. Although endometrial cancer is more common in Caucasian women, higher mortality is found in African Americans who also show higher incidence of obesity. Here, we describe how obesity signals (estrogen, leptin, leptin induced-molecules, Notch; cytokines and growth factors) could affect endometrial cancer. Leptin signaling and its crosstalk may be associated to the more aggressive and poor prognosis type II endometrial cancer, which affects more postmenopausal and African-American women. In this regard, studies on expression of novel molecular markers (Notch, interleukin-1 and leptin crosstalk outcome) may provide essential clues for detection, prevention, treatment and prognosis.
Obesity-related proliferative diseases: the interaction between adipose tissue and estrogens in post-menopausal women
Authors: Vicennati Valentina , Garelli Silvia , Rinaldi Eleonora , Rosetti Sara , Zavatta Guido , Pagotto Uberto , Pasquali Renato 
Published: March 2015

Abstract
Epidemiological studies have shown that overweight and cancer are closely related, even though obesity alone does not apparently heighten cancer risk by the same amount. Given the low overall risk of all cancers with obesity, it is unlikely that obesity alone causes cancer, but should instead be considered as a tumor promoter. There are three main hypotheses that could explain how obesity might contribute to cancer development and growth: the inflammatory cytokines from adipose tissue hypothesis, the insulin resistance and hyperinsulinemia hypothesis, and the unopposed estrogen cancer hypothesis. The link between obesity and cancer is that adipocytes constitute a major component of the tumor microenvironment for breast and abdominally metastasizing cancers, promoting tumor growth. This review will mainly focus attention on the relationship between adipose tissue, estrogens, and cancer risk.
Adiposity and metabolic dysfunction in polycystic ovary syndrome
Authors: Sam Susan 
Published: March 2015

Abstract
Polycystic ovary syndrome (PCOS) is the most common hormonal disorder among reproductive-age women and is associated with a high risk for metabolic disorders. Adiposity and insulin resistance are two prevalent conditions in PCOS and the likely culprits for the heightened metabolic risk. Up to 60% of women with PCOS are considered to be overweight or obese, and even among non-obese women with PCOS there is an increased accumulation of adipose tissue in abdominal depots. Insulin resistance in PCOS is unique and independent of obesity, as even non-obese women with this condition are frequently insulin resistant. However, obesity substantially aggravates the insulin resistance and the metabolic and reproductive abnormalities in women with PCOS. Recently, it has been shown that many aspects of adipose tissue function in PCOS are abnormal, and these abnormalities likely predispose to development of insulin resistance even in the absence of obesity. This review provides an overview of these abnormalities and their impact on development of metabolic disorders. At the end, an overview of the therapeutic options for management of adiposity and its complications in PCOS are discussed.
Die Suche nach Prävention. Naturgefahren im 19. und 20. Jahrhundert
Authors: Hannig Nicolai 
Published: March 2015

Zusammenfassung
Der Schutz vor Naturgefahren, deren Bewältigung, aber auch Überwältigung gehören seit jeher zu den Bedingungen gesellschaftlicher Entwicklungen. Vorsorge und Prävention gelten jedoch als weitaus jüngere Haltungen, die mit der Wende zum 19. Jahrhundert an Bedeutung gewannen. Beide sind, ganz ähnlich wie die Herstellung von Sicherheit, Variationen ein und derselben Haltung gegenüber der Zukunft, die man nicht mehr passiv auf sich zukommen ließ, sondern aktiv zu bearbeiten versuchte. Neuere Forschungen erzählen die Präventionsgeschichte zumeist als Geschichte der Individualisierung, in der der einstige Vorsorgestaat seine Bürger immer mehr in die vorsorgende Selbstverantwortung entließ. Im Umgang mit Naturgefahren zeigt sich jedoch ein umgekehrter Prozess, der eher Formen der Verstaatlichung und Professionalisierung erkennen lässt. Der Aufsatz konzeptualisiert in einem ersten Schritt den Mehrwert, der sich aus einer präventionshistorischen Perspektive ergibt. Im Folgenden analysiert er anhand von Quellen aus Politik, Kultur, Wissenschaft und Wirtschaft exemplarisch die Geschichte der Naturgefahrenprävention und zeigt die gesellschaftlichen Konflikte auf, die präventives Zukunftshandeln im 19. und 20. Jahrhundert mit sich brachte.
Preparation and characteristics of polypropylene-clay nanocomposite fibers
Authors: Mohan T.P. , Kanny Krishnan 
Published: March 2015

Abstract
The objective of this work was to find a possible engineering application for polypropylene (PP) by preparing fibers filled with nanoclay particles. Unfilled and nanoclay filled (0–5 wt%) PP fibers were continuously drawn and examined. The surface morphology and topographic studies of fibers were carried out using a scanning electron microscope (SEM). It was observed that unfilled PP fibers possess poor density distribution with the nonuniform diameter across the fiber length affecting structural integrity. However, PP fibers filled with ≥2 wt% nanoclay had shown improvement in structural integrity. The structure and morphology of fibers were examined by using X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis, and the result indicated good dispersion of nanolayers of clay in PP matrix with exfoliated nanocomposite structure up to 2 wt% nanoclay and above 2 wt% showing intercalated nanocomposite structure. Improved tensile, thermal and water barrier properties of nanoclay filled PP were also observed.