bluuebunny/crossref_metadata_2025 huggingface dataset:
MODEL ESTIMATES FOR GENERATION AND DISTRIBUTION FROM NATIONAL TRAVELS OF TRANSPORT OF AIR CARGO BETWEEN MAJOR CITIES IN COLOMBIA
Authors: Mercado Cervera Hugo José
Published: October 2016

This paper presents models of generation, extraction and distribution of travel for air cargo between the main cities of Colombia. To develop the work we use information of cargo movement in Colombia during 2012, from then, we make the performance analysis and modeling to estimate future behavior considering possible scenarios. The generation model analyzed statistical variables such as population, distance between the main cities of Colombia, the gross domestic product of the cities, indicators of industrial density, the level of unemployment, among other characteristics to determine their influence on transport domestic air cargo. For travel distribution model, including the gravitational, allowed to predict the behavior of air freight, under the hypothetical situation that the Colombian Caribbean coast will have a joint cargo airport that meets the needs of Barranquilla, Santa Marta and Cartagena. The results showed that despite the geographical situation of the cities, this is feasible, given that centralize the management of the three coastal cities in a specialized cargo airport could reduce generalized costs and encourage greater trade with the rest of the cities of Colombia, as demonstrated in the model.DOI: http://dx.doi.org/10.4995/CIT2016.2016.2460
Comparativa en las pautas de movilidad entre estaciones periférica y céntrica de alta velocidad: los casos de Alicante y Villena
Authors: Bautista Rodríguez David , Ortuño Padilla Armando
Published: October 2016

En esta ponencia se tratan de evaluar las diferencias en los patrones de movilidad de los viajeros en una estación de alta velocidad periférica -Villena- y otra céntrica -Alicante- tras la puesta en servicio de la alta velocidad correspondiente al corredor Madrid – Levante en junio de 2013.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3206
Designing Sustainable Systems for Urban Freight Distribution through techniques of Multicriteria Decision Analysis
Authors: Muerza Victoria , Larrodé Emilio , Moreno- Jiménez José María
Published: October 2016

This paper focuses on the analysis and selection of the parameters that have a major influence on the optimization of the urban freight distribution system by using sustainable means of transport, such as electric vehicles. In addition, a procedure has been be studied to identify the alternatives that may exist to establish the best system for urban freight distribution, which suits the stage that is considered using the most appropriate means of transportation available. To do this, it has been used the Analytic Hierarchy Process, one of the tools of multicriteria decision analysis. In order to establish an adequate planning of an urban freight distribution system using electric vehicles three hypotheses are necessary: (i) it is necessary to establish the strategic planning of the distribution process by defining the relative importance of the strategic objectives of the process of distribution of goods in the urban environment, both economically and technically and in social and environmental terms; (ii) it must be established the operational planning that allows the achievement of the strategic objectives with the most optimized allocation of available resources; and (iii) to determine the optimal architecture of the vehicle that best suits the operating conditions in which it will work and ensures optimum energy efficiency in operation.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3304
Analytical methods and simulation models to assess innovative operational measures and technologies for rail port terminals: the case of Valencia Principe Felipe terminal
Authors: Ricci Stefano
Published: October 2016

The topic of freight transport by rail is a complex theme and, in recent years, a main issue of European policy. The legislation evolution and the White Paper 2011 have demonstrated the European intention to re-launch this sector. The challenge is to promote the intermodal transport system to the detriment of road freight transport. In this context intermodal freight terminals, play a primary role for the supply chain, they are the connection point between the various transport nodes and the nodal points where the freight are handled, stored and transferred between different modes to final customer. To achieve the purpose, it is strengthen the improvement of existing intermodal freight terminals and the development of innovative intermodal freight terminals towards higher performance (ERRAC, 2012). Many terminal performances improvements have been proposed and sometime experimented. They are normally basing on combinations of operational measures and innovative technologies (e.g. automatic horizontal and parallel storage and handling, automated gate and sensors for tracking systems data exchange) tested in various terminals, with often-contradictory results. The research work described in this paper (developed within the Capacity4Rail EU project) focusses on the assessment of effects that these innovations can have in the intermodal freight terminals combined in various alternative consistent effective scenarios. The methodological framework setup to assess these innovations is basing on a combination of analytical methods based on sequential algorithms and discrete events simulation models. The output of this assessment method are key performance indicators (KPIs) selected according to terminals typologies and related to different aspects (e.g. management, operation and organization). The present paper illustrates the application of the methodological framework, tuned on the operation of various intermodal terminals, for the validation on today operation and the assessment of possible future scenarios to the case study of the Principe Felipe sea-rail terminal in Valencia.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3406
Transport engineering and reduction in crime: the Medellín case
Authors: Colomer Bea David
Published: October 2016

This study analyses the impact of the aerial cable car public transport system, locally known as Metrocable, in Medellín (Colombia), on the reduction in crime. As part of the municipal policies of social urbanism, Metrocable has contributed to the social integration of the population in the outlying neighbourhoods, which has increased safety in Medellín. This case is clearly of great interest from the point of view of Criminal Sciences, demonstrating how crime can be combated by using tools beyond ius puniendi. DOI: http://dx.doi.org/10.4995/CIT2016.2016.3434
Análisis de Sensibilidad de una Metodología de Decisión Multicriterio desarrollada para la Selección de Tipologías de Estructuras de Contención en una Autovía Urbana
Authors: MUÑOZ BELEN , ROMANA MANUEL , ORDOÑEZ JAVIER
Published: October 2016

Los métodos de decisión multicriterio son una herramienta que reduce la subjetividad en la toma de decisiones mediante la creación de una serie de filtros de selección y ayuda a la elección entre alternativas complejas. Permite a los proyectistas estructurar la información de forma racional y poder exponerla de forma clara, así como la identificación precisa y ordenada todos los elementos que determinan que un diseño sea el idóneo, y al mismo tiempo se consideren y valoren todas las alternativas posibles que da solución al problema. Pueden tener propósitos diferentes en cada una de las etapas de selección de alternativas, en primer lugar puede ayudar a analizar el problema, tarea u objetivo al descomponerlo en un número finito de requisitos, y una vez establecido los requisitos ayuda a su ordenación por la importancia relativa o peso de cada criterio para cada alternativa. Frente a estas ventajas, presentan un inconveniente muy importante que es la subjetividad a la hora de asignar pesos a cada criterio y la valoración de las diferentes alternativas por el decisor. En la presente comunicación se realiza un análisis de sensibilidad que valida la metodología desarrollada en el marco de una investigación que establece un proceso sistemático de decisión a partir de la aplicación de forma secuencial de varios métodos de decisión multicriterio, de manera que se  reduzca en todo lo posible la subjetividad asociada a cualquier proceso de decisión. El análisis de sensibilidad determina cómo varía la selección de alternativas cuando varía la importancia relativa de los criterios o requerimientos de proyecto considerados como determinantes en el proceso de selección.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3491
COMPARATIVE STUDY OF LIBERALIZATION PROCESS OF PASSENGERS RAILWAY MARKET IN SPAIN AND ENGLAND
Authors: Fernández Aracil Patricia , Fernández Morote Graciela , Ortuño Padilla Armando
Published: October 2016

This article provides an overview of the privatization of railway passengers market in Spain through a background to the most relevant cases studies in Europe, particularly the liberalization process in England. The English case study is a paradigmatic example to assess how the liberalization process was developed and its effect in the present. This assessment has been undertaken to analyse the railway franchise structure, ticketing measures, role of national and regional authorities, etc. and possible analogies to be adapted to the case of Spain. Firstly, this article reviews the origin of the privatization of the railway market in both Spain and England, describing every phase of the liberalization and the success of every stage. Secondly, a critical approach assessment exposes those market failures of the liberalization process in England that caused negative impacts on        society. In addition, the role of the Government is analysed to measure their implication in order to solve that situation. Furthermore, the paper expounds a wide analysis of the rail ticketing in England, its effects on increased passenger number. Finally, this article proposes some measures to be followed on the privatization of passenger rail market in Spain, as well as some key concepts to guarantee its success as taken from the case studies that have been reviewed.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3522
Evaluación de la red de carreteras y su impacto en costos y tiempos de viaje en una región del norte de Colombia
Authors: ARANGO PASTRANA CARLOS ALBERTO , VERGARA RODRIGUEZ CESAR JOSE
Published: October 2016

El transporte es una actividad fundamental dentro de la sociedad, todas las personas a diario se benefician de los servicios de transporte para desarrollar sus actividades cotidianas. Para gestionar los sistemas de transporte en una región geográfica es necesario contar con información técnica de las vías, pero diversos estudios han demostrado que los países Latinoamericanos no cuentan con eficiente información técnica de su red de carreteras. Este problema afecta la sociedad en varios niveles de forma simultanea ya que el transporte moviliza personas pero también los bienes que son consumidos por estas. El caso Colombiano no es ajeno a la realidad Latinoamericana y en algunas regiones del país el problema es aún mayor ya que la información de muchas vías no corresponde a la información que registra el Ministerio de Transporte. En este trabajo se diagnosticó la red vial del Departamento de Sucre, ubicado en la región norte de Colombia, realizando un análisis del estado del asfalto, señalización, número de carriles y velocidad de conducción. Lo anterior permitió evaluar las carreteras seleccionadas realizando una comparación con la información disponible por el ministerio de transporte, dando como resultado una matriz de inconsistencias entre la información disponible con la recolectada. Finalmente se midió el impacto en los costos y tiempos de viaje que se realizan en esta región del País.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3527
Environmental innovation through transport policy. The implementation of the free fare policy on public transport in Tallinn, Estonia
Authors: Gabaldón-Estevan Daniel
Published: October 2016

Urban areas are of increasing relevance when it comes to sustainability. •      First, about half of the world’s population now lives in cities (increasing to 60% by 2030). •      Second, cities are nowadays responsible for levels of resource consumption and waste generation that are higher beyond their share on world population. •      Third, cities are more vulnerable to disruptive events that can lead to restrictions on the provision of resources and to changes on the environment caused by climate change. •      And fourth, because they concentrate key resources (political, social, cultural…), cities are seen as strategic scenarios where to experiment and develop solutions to cope with the prevailing sustainability challenges driven by the major social and environmental transformations. Urban agglomerations can be seen as complex innovation systems where human activities are shaped in order to transform societies towards sustainable development. For this paper, we focus on the case of an environmental innovation regarding transport policy, the implementation of the fare-free policy on public transport for all inhabitants of Tallinn, Estonia. Tallinn, with 414,000 inhabitants in 2015, is the capital of Estonia and the largest city in the country. Over the last two decades the share of public transport trips decreased dramatically. After a public opinion poll in 2012, in which over 75% of the participants voted for a fare-free public transportation system (FFPTS) in Tallinn, the new policy was implemented on 1st January 2013. From that date on inhabitants of Tallinn could use all public transport services (busses, trams, trolly-busses) operated by city-run operators for free. Later the fare-free system was implemented also on trains within Tallinn. In this paper we analyze the context, in which this policy was implemented, the main characteristics of its implementation and its actual situation.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3532
Design and development of driving simulator scenarios for road validation studies
Authors: Dols Ruiz Juan Fco.
Published: October 2016

In recent years, the number of road-based studies using driving simulators is growing significantly. This allows evaluating controlled situations that otherwise would require disproportionate observations in time and/or cost. The Institute of Design and Manufacturing (IDF) of the Polytechnic University of Valencia (UPV) has developed, in collaboration with the Engineering Research Group Highway (GIIC) of the UPV, a low cost simulator that allows rapid implementation and effectively a new methodology for validation studies of different roads through the implementation in the simulator scenarios of existing roads. This methodology allows the development of new scenarios based on the analysis of a layers-file system. Each layer includes different information from the road, such as mapping, geometry, signaling, aerial photos, etc. The creation of the simulated scenario is very fast based on the geometric design software, making it easier to consulting firms using the system that can evaluate and audit a particular route, obtaining reliable conclusions at minimal cost, even if the road is not actually built. This paper describes the basic structure of the layers generated for developing scenarios and guidelines for the implementation thereof. Finally the application of this methodology to a case of success will be described.DOI: http://dx.doi.org/10.4995/CIT2016.2016.4088
Modelos para la reordenación de la red de transporte público en la Comarca de Pamplona
Authors: Stührmann Henning , Perez Lozano José Maria , Maldonado Riesgo Guillermo , Díaz Carrero José Luis
Published: October 2016

Para diseñar y evaluar alternativas la reordenación de transporte público en Pamplona se desarrollaron herramientas de modelización de dos aspectos fundamentales del sistema de transporte: Un modelo económico y de explotación, que relaciona la operación de las líneas con el resultado económico del operador de transporte público, yUn modelo de la movilidad, que relaciona la oferta en transporte público con su demanda El primero se compone de un representación detallada de los parámetros de explotación de cada línea (kilómetros recorridos, nº de expediciones, horas de conducción, material móvil), y de un modelo económico que relaciona los costes reales del operador de transporte público con parámetros de explotación. Permite inferir así el resultado económico de otras alternativas de explotación, una vez definidas con detalle su explotación. El segundo es un modelo de la movilidad en cuatro etapas, desarrollado a partir de una encuesta domiciliaria realizada recientemente. Permite estimar la demanda de alternativas de ordenación de la red, y en particular la captada del vehículo privado. Utilizando ambas herramientas fue posible el diseño de alternativas de ordenación de la red que, aun manteniendo prácticamente igual la subvención al sistema de transporte, incrementaban el uso del transporte público. La primera alternativa analizada corresponde a una mejora evolutiva de la actual estructura de red, mientras la segunda, basada en ejes troncales en plataforma exclusiva, constituye una mayor apuesta al transporte público.DOI: http://dx.doi.org/10.4995/CIT2016.2016.4099
ANÁLISIS DE LA LONGITUD DE LAS RECTAS Y SU INFLUENCIA EN LA CONSISTENCIA DEL DISEÑO GEOMÉTRICO DE CARRETERAS CONVENCIONALES
Authors: Garcia Alfredo
Published: October 2016

Los trazados que presentan rectas de elevada longitud fomentan que los conductores circulen a mayores velocidades, pudiendo alcanzar sus velocidades deseadas en la parte central de las mismas. Como consecuencia de ello, son grandes las reducciones de velocidad para afrontar las curvas posteriores. En cambio, con rectas cortas, las velocidades que se pueden desarrollar en las dos curvas de los extremos están condicionadas mutuamente para que no haya una reducción excesiva de la velocidad. Las reducciones excesivas de velocidad comprometen la adecuada consistencia de una carretera por lo que están correlacionadas con una mayor siniestralidad. La mayoría de modelos de velocidad de operación existentes han sido calibrados a partir de mediciones puntuales de velocidad. Para estimar los perfiles de velocidad de operación, se hace necesario incorporar unas reglas de construcción. La gran mayoría de ellas considera que los cambios de velocidad se producen solo a lo largo de la recta. En la investigación que se presenta, se ha analizado el comportamiento operacional de un gran número de conductores en las rectas, encontrando importantes diferencias respecto del comportamiento anterior. Analizando la evolución de la velocidad de operación observada en 70 secciones curva-recta-curva de carreteras convencionales se ha encontrado que la variación de velocidad se produce en una longitud superior a la propia recta; esa nueva longitud efectiva está conformada por la longitud de la recta más un cierto desarrollo de las curvas adyacentes. Los resultados apuntan a que la longitud empleada para variar la velocidad antes y después de las rectas es de unos 145 m, independientemente de la configuración geométrica. Adicionalmente, se han comparado los resultados del análisis geométrico y operacional de las secciones con los criterios correspondientes de la nueva Instrucción de Trazado de Carreteras, encontrando disparidades manifiestas y planteándose mejoras a la misma, siendo el punto de mayor discrepancia las reducidas longitudes que esta emplea para considerar algunas rectas como no independientes. Se han encontrado tres niveles de independencia de las rectas a diferencia de los dos niveles tradicionalmente empleados a nivel internacional.DOI: http://dx.doi.org/10.4995/CIT2016.2016.4119
Metodología para modelizar una red de tráfico en la que se van a obtener datos mediante la técnica del escaneo de matrículas
Authors: Sánchez-Cambronero García-Moreno Santos , Rivas Álvarez Ana María , Barba Contreras Rosa María , Ruiz Ripoll Lidia , Gallego Giner María Inmaculada , Menéndez Martinez José María
Published: October 2016

En el presente artículo se aborda el problema de modelizar una red de tráfico para poder aplicar la técnica del escaneo de matrículas para estimar flujos en ruta, y por tanto obtener la matriz Origen-Destino así como la asignación de la red. Para llevar a cabo dicha modelización se plantea una metodología que trata de manera global la simplificación de la red y que tiene como base la reducción del número de rutas mediante la eliminación de pares Origen-Destino que no tengan una demanda relevante. Dicha simplificación tiene un enfoque práctico muy diferente de la visión tradicional de zonificación y disposición de centroides dentro de la red y que permitirá imbricarla con los modelos de ubicación de dispositivos de escaneo. La metodología permite detectar aquellos arcos de la red que son afectados por la simplificación y las consecuencias sobre la estimación de flujos que puedan derivarse de dicha afección. Con todo ello, se puede establecer una priorización en la ubicación de los equipos de escaneo que permitirá hacer una reconstrucción más fiable de los flujos de la red. Se ha empleado una red basada en la denominada red Nguyen-Dupuis como ejemplo de aplicación de la metodología desarrollada. A través del mismo se irá aclarando paso por paso cada una de las fases del método.DOI: http://dx.doi.org/10.4995/CIT2016.2016.4216
OPEN NOISE BARRIERS BASED ON SONIC CRYSTALS. ADVANCES IN NOISE CONTROL IN TRANSPORT INFRAESTRUCTURES
Authors: Sánchez Pérez Juan Vicente , Peiró Torres María Pilar , Redondo Pastor Javier , Bravo Plana-Sala Jose María
Published: October 2016

Noise control is an environmental problem of first magnitude nowadays. In this work, we present a new concept of acoustic screen designed to control the specific noise generated by transport infrastructures, based on new materials called sonic crystals. These materials are formed by arrangements of acoustic scatterers in air, and provide a new and different mechanism in the fight against noise from those of the classical screens. This mechanism is usually called multiple scattering and is due to their structuring in addition to their physical properties. Due to the separation between scatterers, these barriers are transparent to air and water allowing a reduction on their foundations. Tests carried out in a wind tunnel show a reduction of 42% in the overturning momentum compared to classical barriers. The acoustical performance of these barriers is shown in this work, explaining the new characteristics provided in the control of noise. Finally, an example of these barriers is presented and classified according to acoustic standardization tests. The acoustic barrier reported in this work provides a high technological solution in the field of noise control.DOI: http://dx.doi.org/10.4995/CIT2016.2016.4232
BALANCE DEL PLAN DE MODERNIZACIÓN DE LOS SERVICIOS INTERURBANOS POR AUTOBÚS
Authors: Andújar Martínez Montserrat , Tarruella Vidal Elena , Nieto Corella Berta , León Fariñas María del Amor
Published: October 2016

El Plan de Modernización de los servicios de transporte público regular permanente de viajeros del Consorcio Regional de Transportes de Madrid, aprobado a finales de 2009, tiene como objetivo revitalizar el servicio de transporte en los autobuses urbanos e interurbanos de la Comunidad de Madrid. Este Plan abarca tanto a los vehículos como a la tecnología necesaria para la mejora del servicio y de la información al usuario. Las mejoras llevadas a cabo han implicado unos desarrollos e inversiones cuantiosos como la instalación de los SAEs, implantación del sistema de ticketing sin contacto, instalación de displays embarcados, cámaras de videovigilancia, información en tiempo real a través de diferentes soportes (Pantallas en paradas o intercambiadores, Aplicaciones móviles,…),  adaptación de los vehículos para mejorar la accesibilidad a personas de movilidad reducida,… Tras seis años de intenso trabajo, tanto por parte de la Administración como de las empresas operadoras, se han alcanzado unos estándares elevados en la totalidad de los aspectos, habiéndose cumplido los objetivos perseguidos, con carácter general, como demuestran los resultados de las encuestas de satisfacción a los usuarios. Además, dentro de este marco, en los últimos años, se han ido desarrollando nuevos aspectos tecnológicos, que serán fundamentales para el buen desarrollo de las labores del Consorcio, como son la integración de la información en tiempo real de todos los operadores en el CITRAM, la utilización de las herramientas de gestión de incidencias y afecciones, etc.DOI: http://dx.doi.org/10.4995/CIT2016.2016.4269
Distribution and sources of air pollutants in the North China Plain based on
on-road mobile measurements
Authors: Zhu Yi , Zhang Jiping , Wang Junxia , Chen Wenyuan , Han Yiqun , Ye Chunxiang , Li Yingruo , Liu Jun , Zeng Limin , Wu Yusheng , Wang Xinfeng , Wang Wenxing , Chen Jianmin , Zhu Tong
Published: October 2016

Abstract. The North China Plain (NCP) has been experiencing severe air pollution problems with rapid economic growth and urbanisation. Many field and model studies have examined the distribution of air pollutants in the NCP, but convincing results have not been achieved, mainly due to a lack of direct measurements of pollutants over large areas. Here, we employed a mobile laboratory to observe the main air pollutants in a large part of the NCP from 11 June to 15 July 2013. High median concentrations of sulfur dioxide (SO2) (12 ppb), nitrogen oxides (NOx) (NO + NO2; 452 ppb), carbon monoxide (CO) (956 ppb), black carbon (BC; 5.5 µg m−3) and ultrafine particles (28 350 cm−3) were measured. Most of the high values, i.e. 95 percentile concentrations, were distributed near large cities, suggesting the influence of local emissions. In addition, we analysed the regional transport of SO2 and CO, relatively long-lived pollutants, based on our mobile observations together with wind field and satellite data analyses. Our results suggested that, for border areas of the NCP, wind from outside this area would have a diluting effect on pollutants, while south winds would bring in pollutants that have accumulated during transport through other parts of the NCP. For the central NCP, the concentrations of pollutants were likely to remain at high levels, partly due to the influence of regional transport by prevalent south–north winds over the NCP and partly by local emissions.
Thermodynamic and dynamic responses of the hydrological cycle to
solar dimming
Authors: Smyth Jane E. , Russotto Rick D. , Storelvmo Trude
Published: October 2016

Abstract. The fundamental role of the hydrological cycle in the global climate system motivates thorough evaluation of its responses to climate change and mitigation. The Geoengineering Model Intercomparison Project (GeoMIP) is a global collaboration that aims to assess the climate impacts of solar geoengineering, a proposal to counteract global warming with a reduction of incoming solar radiation. We assess the mechanisms underlying the rainfall response to a simplified simulation of solar dimming in the suite of GeoMIP models and identify robust features. While solar geoengineering restores preindustrial temperatures, the global hydrology is altered. Tropical precipitation changes dominate the response across the model suite. The models indicate a range of possibilities for the hydrological response, and in most cases, both thermodynamic and non-thermodynamic mechanisms drive precipitation minus evaporation changes in the geoengineered simulations relative to the preindustrial. Shifts of the Hadley circulation cells cause greater rainfall anomalies than local changes in relative humidity or the Clausius-Clapeyron scaling of precipitation minus evaporation. The variations among models in the movement of the intertropical convergence zone highlights the need for cautious consideration and continued study before any implementation of solar geoengineering.
Effect of iron oxide on nitrification in two agricultural soils with
different pH
Authors: Huang Xueru , Zhu-Barker Xia , Horwath William R. , Faeflen Sarwee J. , Luo Hongyan , Xin Xiaoping , Jiang Xianjun
Published: October 2016

Abstract. Iron (Fe) affects soil nitrogen (N) cycling processes both in anoxic and oxic environments. The role of Fe in soil N transformations including nitrification, mineralization, and immobilization, is influenced by redox activity, which is regulated by soil pH. The effect of Fe minerals, particularly oxides, on soil N transformation processes depends on soil pH, with Fe oxide often stimulating nitrification activity in the soil with low pH. We conducted lab incubations to investigate the effect of Fe oxide on N transformation rates in two subtropical agricultural soils with low pH (pH 5.1) and high pH (pH 7.8). 15N-labeled ammonium and nitrate were used separately to determine N transformation rates combined with Fe oxide (ferrihydrite) addition. Iron oxide stimulated net nitrification in low-pH soil (pH 5.1), while the opposite occurred in high-pH soil (pH 7.8). Compared to the control, Fe oxide decreased microbial immobilization of inorganic N by 50 % in low-pH soil but increased it by 45 % in high-pH soil. A likely explanation for the effects at low pH is that Fe oxide increased NH3-N availability by stimulating N mineralization and inhibiting N immobilization. These results indicate that Fe oxide plays an important role in soil N transformation processes and the magnitude of the effect of Fe oxide is dependent significantly on soil pH.
Biopolyester-Based Systems Containing Naturally Occurring Compounds with Enhanced Thermo-Oxidative Stability
Authors: Arrigo Rossella , Morici Elisabetta , Dintcheva Nadka Tzankova
Published: October 2016

Background

This work presents a sustainable approach for the stabilization of polylactic acid (PLA) against thermo-oxidative aging.

Methods

Naturally occurring phenolic and polyphenolic compounds, such as ferulic acid (FerAc), vanillic acid (VanAc), quercetin (Querc) and vitamin E (VitE), were introduced into PLA.

Results

The preliminary characterization of the systems formulated containing different amounts of natural stabilizers showed that all compounds used acted as plasticizers, leading to a decrease in rheological functions with respect to neat PLA, without significantly modifying the crystallinity of the raw material. The study of the thermo-oxidative behavior of neat PLA and PLA/natural compound systems, performed by spectrometric and thermal analyses, indicated that all stabilizers considered were able to exert a remarkable antioxidant action against thermo-oxidative phenomena.

Conclusions

All natural compounds considered are thus proposed as ecofriendly stabilizers, to get fully bio-based polymer systems with enhanced thermo-oxidative stability, suitable for biomedical applications.
Establishment of Two Data Mining Models of Lung Cancer Screening Based on Three Gene Promoter Methylations Combined with Telomere Damage
Authors: Wang Wei , Feng Xiaolei , Duan Xiaoran , Tan Shanjuan , Wang Sihua , Wang Tuanwei , Feng Feifei , Wu Yiming , Wu Yongjun
Published: October 2016

Objective

To identify the significance of a support vector machine (SVM) model and a decision tree (DT) model for the diagnosis of lung cancer combined with the detection of fragile histidine triad (FHIT), RAS association domain family 1 (RASSF1A) and cyclin-dependent kinase inhibitor 2A (p16) promoter methylation levels and relative telomere length (RTL) of white blood cells from peripheral blood DNA.

Methods

The levels of p16, RASSF1A and FHIT promoter methylation and the RTL of white blood cells in peripheral blood DNA of 200 healthy individuals and 200 lung cancer patients were analyzed by SYBR Green-based quantitative methylation-specific PCR and quantitative PCR. Based on the 4 biomarkers, SVM and DT models were developed.

Results

The levels of FHIT, RASSF1A and p16 promoter methylation were 3.33 (1.86-6.40) and 2.85 (1.39-5.44) (p = 0.002); 27.62 (9.09-52.86) and 17.17 (3.86-50.87) (p = 0.038); and 0.59 (0.16-4.50) and 0.36 (0.06-4.00) (p = 0.008) in cases and controls, respectively. RTL was 0.93 ± 0.32 and 1.16 ± 0.57 (p<0.001). The areas under the receiver operating characteristic (ROC) curves of the Fisher discriminant analysis, SVM and DT models were 0.670 (0.569-0.761), 0.810 (0.719-0.882) and 0.810 (0.719-0.882), respectively.

Conclusions

The SVM and DT models for diagnosing lung cancer were successfully developed through the combined detection of p16, RASSF1A and FHIT promoter methylation and RTL, which provided useful tools for screening lung cancer.
Duplex Ultrasound for the Prediction of Vascular Events Associated with Arteriovenous Fistulas in Hemodialysis Patients
Authors: Ishii Takeo , Suzuki Yasunobu , Nakayama Takuji , Ohmori Miki , Masai Shinichi , Sasagawa Naru , Ohyama Kunio
Published: October 2016

Objective

To determine if duplex ultrasound (US) for arteriovenous fistulas (AVFs) can predict vascular events (VEs; thrombosis and stenosis).

Methods

Duplex US was performed for vascular access evaluation in 2557 maintenance hemodialysis (HD) patients between October 1, 2013 and March 31, 2016. Of these patients, 2184 patients were finally included in this study. AVF dysfunction was assessed using the brachial artery blood flow volume (Qa; mL/min), arterial blood flow resistance index (RI), and residual diameter of the fistula vein (RD; mm). Proximal, midpoint, and distal aspects of the fistulas were measured. The baseline measurements were the US assessments, and the endpoint was VEs requiring vascular access intervention therapy or vascular surgery. Associations of US findings and VEs were assessed with receiver operating characteristic curve analysis, log-rank analysis, and multivariate Cox hazard models.

Results

The mean Qa was 772.8 ± 441.4 mL/min; RI, 0.56 ± 0.1; and RD, 2.37 ± 1.0 mm. The optimal Qa cut-off point was calculated as 581.5 mL/min, RI cut-off as 0.56, and RD cut-off as 1.85 mm. VEs were more frequent in patients with a Qa <581.5 mL/min than in those with a Qa >581.5 mL/min (p<0.001). In multivariate analysis, Qa, ferritin, transferrin saturation, and warfarin use were significantly associated with VEs.

Conclusions

US evaluation of AVFs in HD patients is a simple method to predict the risks of thrombosis and fistula dysfunction. Qa, ferritin, transferrin saturation, and warfarin use might be associated with VEs.
A Modified de novo Insertion Technique for Catheter Replacement in Elderly Hemodialysis Patients: A Single Clinic Retrospective Analysis
Authors: Wang Lihua , Wei Fang , Chen Haiyan , Sun Guijiang , Yu Haibo , Jiang Aili
Published: October 2016

Purpose

For patients who rely on a tunneled cuffed catheter, replacement or catheter removal is typically necessary. We recently performed a modified de novo insertion technique for catheter replacement in our practice. As the technique has not yet been studied comprehensively, we performed a retrospective study to evaluate the safety and efficacy of de novo placed catheter without delay for catheter replacement in elderly hemodialysis patients.

Methods

A retrospective review of 164 elderly patients was conducted during a period of three years. There were 84 patients in study group, as well as 80 patients in a control group, who had catheter replacement by guidewire exchange technique. Clinical follow-up data was collected.

Results

All catheters were placed successfully. The mean survival time per catheter was 641 catheter days (study group) and 485 catheter days (control group). The primary patency rates of 30 days were 97.7% (study group) and 90% (control group), respectively, with statistically significant difference (p = 0.04). The incidence of catheter infection was not statistically significantly different in both groups (p = 0.586), but the case of catheter dysfunction was significantly lower in study group compared to control group (p = 0.003).

Conclusions

The de novo placed catheter without delay technique for catheter replacement near the pre-existing venotomy site is safe, and boasts similar infection rates with lower dysfunction rates compared to tunneled catheter insertion by guidewire exchange technique.
Does Pre- and Post-Angioplasty Doppler Ultrasound Evaluation Help in Predicting Vascular Access Outcome?
Authors: Guedes-Marques Maria , Maia Pedro A. , Neves Fernando , Ferreira Aníbal , Cruz João , Carvalho Dulce , Oliveira Carlos , Barreto Carlos , Carvalho Telmo , Ponce Pedro
Published: October 2016

Background

Kidney Disease – Improving Global Outcomes (KDIGO) recommends post-percutaneous transluminal angioplasty (PTA) <30% residual stenosis (RS) and hemodynamic parameters improvement. Primary end point: how post-PTA access blood flow (ABF) improvement predicts vascular access (VA) outcome. Secondary: compare Doppler ultrasound (DU) and angiography diagnostic accuracy; determine how other factors predict outcome.

Methods

Eighty patients. DU evaluation performed pre- and post-PTA. Several parameters recorded. Secondary patency verified after 6 months.

Results

Initial ABF 537 ± 248 mL/min; final ABF 1013 ± 354 mL/min. Number and location of stenosis was highly correlated between DU and angiography (p<0.001); central vessels mismatching. First semester overall survival was 63%; significantly better for fistulas (76%) than grafts (51.7%), p 0.044. Final RS>30% associated to better survival, p 0.038. Initial ABF<500 mL/min and multiple stenosis did not affect outcome (p>0.05). A >2-fold ABF increase had no significant impact on fistulas (p>0.05) but was significantly associated with worst outcomes in grafts (23.1% vs. 73.5%, p 0.009). Grafts had lower survival (HR 3.3, p 0.034).

Conclusions

Although less accurate for central lesions, DU has a key role on VA surveillance, allowing a morphologic and hemodynamic assessment. Angioplasty is effective in preserving VA; however, it may increase restenosis due to accelerated neointimal hyperplasia. Current parameters are not useful. Trials addressing this issue are needed.
Data Quality in Rare Cancers Registration: The Report of the RARECARE Data Quality Study
Authors: Trama Annalisa , Marcos-Gragera Rafael , Sánchez Pérez Maria Josè , van der Zwan Jan Maarten , Ardanaz Eva , Bouchardy Christine , Melchor Juan Manuel , Martinez Carmen , Capocaccia Riccardo , Vicentini Massimo , Siesling Sabine , Gatta Gemma ,   and the RARECARE working group contributing to the data quality study
Published: October 2016

Purpose

Rare cancers represent 22% of all tumors in Europe; however, the quality of the data of rare cancers may not be as good as the quality of data for common cancer. The project surveillance of rare cancers in Europe (RARECARE) had, among others, the objective of assessing rare cancer data quality in population-based cancer registries (CRs). Eight rare cancers were considered: mesothelioma, liver angiosarcoma, sarcomas, tumors of oral cavity, CNS tumors, germ cell tumors, leukemia, and malignant digestive endocrine tumors.

Methods

We selected data on 18,000 diagnoses and revised, on the basis of the pathologic and clinical reports (but not on pathologic specimens), unspecified morphology and topography codes originally attributed by CR officers and checked the quality of follow-up of long-term survivors of poor prognosis cancers.

Results

A total of 38 CRs contributed from 13 European countries. The majority of unspecified morphology and topography cases were confirmed as unspecified. The few unspecified cases that, after the review, changed to a more specific diagnosis increased the incidence of the common cancer histotypes. For example, 11% of the oral cavity epithelial cancers were reclassified from unspecified to more specific diagnoses: 8% were reclassified as squamous cell carcinoma (commoner) and only 1% as adenocarcinoma (rarer). The revision confirmed the majority of long-term survivors revealing a relative high proportion of mesothelioma long-term survivors. The majority of appendix carcinoids changed behavior from malignant to borderline lesions.

Conclusions

Our study suggests that the problem of poorly specified morphology and topography cases is mainly one of difficulty in reaching a precise diagnosis. The awareness of the importance of data quality for rare cancers should increase among registrars, pathologists, and clinicians.
Vestibular Schwannomas Treated with Cyberknife®: Clinical Outcomes
Authors: Jumeau Raphaël , Bondiau Pierre-Yves , Parietti-Winkler Cécile , Salleron Julia , Civit Thierry , Peiffert Didier , Bernier-Chastagner Valérie
Published: October 2016

Purpose

Fractionated stereotactic radiotherapy (FSR) is a recognized treatment for vestibular schwannomas (VS). This study's aim is to present clinical outcomes and local control (LC) results for patients with VS treated with FSR using the Cyberknife® (CK) in 2 French cancer centers.

Methods

Patients treated with FSR for VS between 2007 and 2012 were retrospectively analyzed. Local control was determined using follow-up MRI. The hearing preservation (HP) rate was determined by analyzing pretreatment and posttreatment audiograms.

Results

Forty patients were treated for VS with the CK in both centers. The mean maximal VS dimension was 18.3 mm (range 3–30). The median follow-up was 36 months and the LC was 97% at 3 years of follow-up and 89% after 5 years. The HP rate was 83% and no facial nerve impairment was reported.

Conclusions

Our results in terms of LC and HP rate are congruent with similar studies that use the CK to treat VS. It appears that the CK is safe and efficient in VS management even for large lesions. Further studies with larger cohorts are warranted.
3D Vision Improves Outcomes in Early Cervical Cancer Treated with Laparoscopic Type B Radical Hysterectomy and Pelvic Lymphadenectomy
Authors: Raspagliesi Francesco , Bogani Giorgio , Martinelli Fabio , Signorelli Mauro , Scaffa Cono , Sabatucci Ilaria , Lorusso Domenica , Ditto Antonino
Published: October 2016

Purpose

To evaluate the alterations on surgical outcomes after of the implementation of 3D laparoscopic technology for the surgical treatment of early-stage cervical carcinoma.

Methods

Data of patients undergoing type B radical hysterectomy (with or without bilateral salpingo-oophorectomy) and pelvic lymphadenectomy via 3D laparoscopy were compared with a historical cohort of patients undergoing type B radical hysterectomy via conventional laparoscopy. Complications (within 60 days) were graded per the Accordion severity system.

Results

Data of 75 patients were studied: 15 (20%) and 60 (80%) patients undergoing surgery via 3D laparoscopy and conventional laparoscopy, respectively. Baseline patient characteristics as well as pathologic findings were similar between groups (p>0.1). Patients undergoing 3D laparoscopy experienced a trend toward shorter operative time than patients undergoing conventional laparoscopy (176.7 ± 74.6 vs 215.9 ± 61.6 minutes; p = 0.09). Similarly, patients undergoing 3D laparoscopic radical hysterectomy experienced shorter length of hospital stay (2 days, range 2-6, vs 4 days, range 3-11; p<0.001) in comparison to patients in the control group, while no difference in estimated blood loss was observed (p = 0.88). No between-group difference in complication rate was observed.

Conclusions

3D technology is a safe and effective way to perform type B radical hysterectomy and pelvic node dissection in early-stage cervical cancer. Further large prospective studies are warranted in order to assess the cost-effectiveness of the introduction of 3D technology in comparison to robotic assisted surgery.
Reviewer Acknowledgements for Environment and Natural Resources Research, Vol. 6, No. 3
Authors: Lee Joan
Published: October 2016

Reviewer Acknowledgements for Environment and Natural Resources Research, Vol. 6, No. 3, 2016
Estimation of Shelf Life of Mango Juice Produced Using Small-Scale Processing Techniques
Authors: Mkandawire Wezi , Ngongola-Manani Tinna Austen , Kabambe Orpa M , Kampanje-Phiri Jessica
Published: October 2016

The objective of this study was to estimate shelf life of mango juice produced using small-scale processing techniques. Juice was processed and packaged in 80 plastic bottles and stored at 13 oC and 30 oC. At each temperature, 20 bottles had preservative (0.5 mg/l sodium benzoate) and 20 bottles had no preservative. The juices were analyzed for pH, vitamin C, sensory attributes and microbial load at two week intervals for six weeks. From week 2 to week 6, juices stored at 30 oC had lower pH values (3.15 – 2.80 with preservative, 3.60 – 2.6 without preservative) than juices stored at 13 oC (4.20 - 3.80 with preservative, 4.15 - 3.70 without preservative ) and the differences were significant (p<0.05). At 6 weeks, vitamin C loss was highest (79%) in juice without preservative stored at 30 oC, followed by juice stored at 30 oC with preservative (71.43%). The loss was lowest (26.98%) in juice with preservative stored at 13 oC. Significant differences (p<0.05) in color were observed at week 6 between juices stored at 13 oC (4.5 with preservative and 4.66 without preservative) and 30 oC (5.02 with preservative and 7.00 without preservative). Juices stored at 30 oC were rated ‘bad’ from week 2, in smell (5.91 and 6.25) and taste (5.66 and 6.91) while at that time, juices stored at 13 oC were rated ‘almost similar’ to fresh juice in smell (4.25) and taste (4.25 and 4.58). Storage at 13 oC with preservative resulted in lowest bacteria (2.04 x 104 CFU/ml) and yeast and mold (1.72 x 104 CFU/ml) counts whilst highest bacteria (2.10 x 108 CFU/ml) and yeast and mold (1.96 x 108 CFU/ml) counts were observed in juices stored at 30 oC without preservative. The shelf life was estimated based on taste and smell as 2 weeks and 4 weeks for juices stored at 30 oC and 13 oC, respectively. Chilling combined with use of preservative slowed down rate of vitamin C loss, deterioration of sensory attributes and microbial growth.
Prevention of Post-operative Delirium in the Elderly Using Pharmacological Agents
Authors: Tremblay Patrice , Gold Susan
Published: October 2016

IntroductionPost-operative delirium (POD) is a serious surgical complication that can cause significant morbidity and mortality. It is associated with prolonged hospital stay, delayed admission to rehabilitation programs, persistent cognitive deficits, marked health-care costs, and more. The pathophysiology is multifactorial and not completely understood, which complicates the optimal management. Non-pharmacological measures have been the mainstay of treatment, but there has been an ongoing interest in the medical literature on the prevention of post-operative delirium using medications. The purpose of this review is to critically analyze the current evidence on pharmacological prevention of POD.MethodsA literature review was conducted using PubMed and Embase databases, using the following search terms: delirium, antipsychotics, cholinesterase inhibitors, and statins.ResultsA total of 1,152 articles were screened and 25 articles were reviewed. Fourteen articles found a reduced incidence of post-operative delirium using pharmacological agents: eight with antipsychotics, two with statins, one with melatonin, one with dexamethasone, one with gabapentin, and one with diazepam. However, study designs, methodological issues, or authors’ interpretations raise questions on these conclusions.ConclusionsFurther double-blinded randomized clinical trials should be conducted before administering pharmacological agents to reduce POD in a non-research setting.